WorldWideScience

Sample records for included geophysical geochemical

  1. Predictive geophysics: geochemical simulations to geophysical targets

    Science.gov (United States)

    Chopping, R. G.; Cleverley, J.

    2017-12-01

    With an increasing focus on deep exploration for covered targets, new methods are required to target mineral systems under cover. Geophysical responses are driven by physical property contrasts; for example, density contrasts provide a gravity signal, acoustic impedance contrasts provide a seismic reflection signal. In turn, the physical properties for basement, crystalline rocks which host the vast majority of mineral systems are determined almost wholly by the mineralogy of the rocks in question. Mineral systems, through the transport of heat and reactive fluids, will serve to modify the physical properties of country rock as they chemically alter the hosting strata. To understand these changes, we have performed 2D reactive transport modelling that simulates the formation of Archean gold deposits of the Yilgarn Craton, Western Australia. From this, we derive a model of mineralogy that we can use to predict the density, magnetic susceptibility and seismic reflection changes associated with ore formation. It is then possible to predict the gravity, magnetic and seismic reflection responses associated with these deposits. Scenario mapping, such as testing the ability to resolve buried ore bodies or the geophysical survey spacing required to resolve the mineral system, can be performed to produce geophysical targets from these geochemical simulations. We find that there is a gravity response of around 9% of the unaltered response for deposits even buried by 1km of cover, and there is a magnetic spike associated with proximal alteration of the ore system. Finally, seismic reflection response is mostly characterised by additional reflections along faults that plumb the alteration system.

  2. Geophysical and geochemical techniques for exploration of hydrocarbons and minerals

    International Nuclear Information System (INIS)

    Sittig, M.

    1980-01-01

    The detailed descriptive information in this book is based on 389 US patents that deal with geophysical and geochemical techniques useful for the exploration of hydrocarbons and minerals. Where it was necessary to round out the complete technological picture, a few paragraphs from cited government reports have been included. These techniques are used in prospecting for oil, coal, oil shale, tar sand and minerals. The patents are grouped under the following chapters: geochemical prospecting; geobiological prospecting; geophysical exploration; magnetic geophysical prospecting; gravitational geophysical prospecting; electrical geophysical prospecting; nuclear geophysical prospecting; seismic geophysical prospecting; and exploratory well drilling. This book serves a double purpose in that it supplies detailed technical information and can be used as a guide to the US patent literature in this field. By indicating all the information that is significant, and eliminating legal jargon and juristic phraseology, this book presents an advanced, industrially oriented review of modern methods of geophysical and geochemical exploration techniques

  3. Integrated geophysical-geochemical methods for archaeological prospecting

    OpenAIRE

    Persson, Kjell

    2005-01-01

    A great number of field measurements with different methods and instruments were conducted in attempts to develop a method for an optimal combination of various geochemical and geophysical methods in archaeological prospecting. The research presented in this thesis focuses on a study of how different anthropogenic changes in the ground can be detected by geochemical and geophysical mapping and how the results can be presented. A six-year pilot project, Svealand in Vendel and Viking periods (S...

  4. The Earth's heterogeneous mantle a geophysical, geodynamical, and geochemical perspective

    CERN Document Server

    Khan, Amir

    2015-01-01

    This book highlights and discusses recent developments that have contributed to an improved understanding of observed mantle heterogeneities and their relation to the thermo-chemical state of Earth's mantle, which ultimately holds the key to unlocking the secrets of the evolution of our planet. This series of topical reviews and original contributions address 4 themes. Theme 1 covers topics in geophysics, including global and regional seismic tomography, electrical conductivity and seismic imaging of mantle discontinuities and heterogeneities in the upper mantle, transition zone and lower mantle. Theme 2 addresses geochemical views of the mantle including lithospheric evolution from analysis of mantle xenoliths, composition of the deep Earth and the effect of water on subduction-zone processes. Theme 3 discusses geodynamical perspectives on the global thermo-chemical structure of the deep mantle. Theme 4 covers application of mineral physics data and phase equilibrium computations to infer the regional-scale ...

  5. geophysical and geochemical characterization of zango abattoir

    African Journals Online (AJOL)

    Dr A.B.Ahmed

    disposal of hazardous materials, fresh groundwater supplies ... in the groundwater flow system may change considerably the conductivity of the polluted zone; hence the Geo-electric and. Electromagnetic (EM) geophysical methods could effectively be ... this field strength and phase displacement around a fracture zone.

  6. Application of integrated Landsat, geochemical and geophysical data in mineral exploration

    International Nuclear Information System (INIS)

    Conradsen, K.; Nilsson, G.; Thyrsted, T.; Gronlands Geologiske Undersogelse, Copenhagen, Denmark)

    1985-01-01

    In South Greenland (20000 sq. km) a remote sensing investigation is executed in connection with uranium exploration. The investigation includes analysis of Landsat data, conversion of geological, geochemical and geophysical data to image format compatible with Landsat images, and analysis of the total set of integrated data. The available geochemical data consisted of samples from 2000 sites, analyzed for U, K, Rb, Sr, Nb, Ga, Y, and Fe. The geophysical data comprised airborne gamma-spectrometric measurements and aeromagnetic data. The interpolation routines consisted of a kriging procedure for the geochemical data and a minimum curvature routine for the geophysical data. The analysis of the integrated data set is at a preliminary stage. As example a composite image showing Landsat channel 7, magnetic values, and Fe values as respectively intensity, hue and saturation is analyzed. It reveals alkaline intrusions and basaltic layers as anomalies while other anomalies cannot be accounted for on the basis of the present geological knowledge. 12 references

  7. Development of geophysical and geochemical data processing software based on component GIS

    International Nuclear Information System (INIS)

    Ke Dan; Yu Xiang; Wu Qubo; Han Shaoyang; Li Xi

    2013-01-01

    Based on component GIS and mixed programming techniques, a software which combines the basic GIS functions, conventional and unconventional data process methods for the regional geophysical and geochemical data together, is designed and developed. The software has many advantages, such as friendly interface, easy to use and utility functions and provides a useful platform for regional geophysical and geochemical data processing. (authors)

  8. The Nasca and Palpa geoglyphs: geophysical and geochemical data

    Science.gov (United States)

    Hartsch, Kerstin; Weller, Andreas; Rosas, Silvia; Reppchen, Gunter

    2009-10-01

    The Nasca geoglyphs in the stone desert in southern Peru are part of our world cultural heritage. These remarkable drawings have roused the interest of scientists from different disciplines. Here we report the results of integrated geophysical, petrophysical, mineralogical, and geochemical investigations of the geoglyphs at six test sites in the stone desert around Nasca and Palpa. The geomagnetic measurements revealed clear indications of subsurface structures that differ from the visible surface geoglyphs. The high-resolution geoelectrical images show unexpected resistivity anomalies underneath the geoglyphs down to a depth of about 2 m. Remarkable structures were revealed in both vertical and lateral directions. No evidence was found of geochemical or mineralogical alterations of the natural geogenic materials (desert pavement environment versus geoglyphs). Neither salts nor other mineral materials were used by the Nasca people to alter or prepare the surfaces of geoglyphs. This supports the hypothesis that the Nasca people simply removed stone material down to the natural hard pan horizon to create the geoglyphs.

  9. Carbon Sequestration in Unconventional Reservoirs: Geophysical, Geochemical and Geomechanical Considerations

    Science.gov (United States)

    Zakharova, Natalia V.

    In the face of the environmental challenges presented by the acceleration of global warming, carbon capture and storage, also called carbon sequestration, may provide a vital option to reduce anthropogenic carbon dioxide emissions, while meeting the world's energy demands. To operate on a global scale, carbon sequestration would require thousands of geologic repositories that could accommodate billions of tons of carbon dioxide per year. In order to reach such capacity, various types of geologic reservoirs should be considered, including unconventional reservoirs such as volcanic rocks, fractured formations, and moderate-permeability aquifers. Unconventional reservoirs, however, are characterized by complex pore structure, high heterogeneity, and intricate feedbacks between physical, chemical and mechanical processes, and their capacity to securely store carbon emissions needs to be confirmed. In this dissertation, I present my contribution toward the understanding of geophysical, geochemical, hydraulic, and geomechanical properties of continental basalts and fractured sedimentary formations in the context of their carbon storage capacity. The data come from two characterization projects, in the Columbia River Flood Basalt in Washington and the Newark Rift Basin in New York, funded by the U.S. Department of Energy through Big Sky Carbon Sequestration Partnerships and TriCarb Consortium for Carbon Sequestration. My work focuses on in situ analysis using borehole geophysical measurements that allow for detailed characterization of formation properties on the reservoir scale and under nearly unaltered subsurface conditions. The immobilization of injected CO2 by mineralization in basaltic rocks offers a critical advantage over sedimentary reservoirs for long-term CO2 storage. Continental flood basalts, such as the Columbia River Basalt Group, possess a suitable structure for CO2 storage, with extensive reservoirs in the interflow zones separated by massive impermeable

  10. Geochemical and Geophysical Signatures of Poas Volcano, Costa Rica

    Science.gov (United States)

    Martinez, M.; van Bergen, M.; Fernandez, E.; Takano, B.; Barboza, V.; Saenz, W.

    2007-05-01

    still remains open to a question if they will play a helpful role as a geophysical monitoring tool in determining the commencement of volcanic events. A range of Poas volcano geochemical and geophysical parameters have been combined to envisage relationships between them and to gain a better insight in the understanding of the Poas volcanic system.

  11. Objective computerized approaches for centralized geophysical and geochemical landscape project planning.

    Directory of Open Access Journals (Sweden)

    Danilyan Eugene Andreevich

    2013-10-01

    Full Text Available At present landscape design does not represent a scientific subject in strict sense, being a superposition of decorative and applied landscape art and the methods of graphic architectural planning. Serving interests of customers, it does not harmonize with the individual needs of the ground based on landscape geochemistry and ecology. Hence, it results in great number of grounds not consistent with each other according to geochemical criteria. In many cases total soil changing, isolation of natural hydrodynamic drainage, introduction of exotic plants interacting with their environment (including abiotic relations take place, it results in disequilibrium in the ground. Ecological system efficiency needs to be constantly artificially maintained, and that does not support its stability. In other words, without maintaining sufficient conditions, it will be influenced by succession with the course of time, as a particular case of potential gradient equalization. Hence, at present there is an acute problem to develop such a concept of landscape design, that, covering ecological requirements of customers, would be mass one, not producing gradient isolation effect and ecologically self-sustaining in given environment at the same time. It is evident, that to meet these requirements, this concept should not be the product of subjective vision of the author, but direct consequence of geophysical and geochemical landscape condition with theoretical development allowing calculation testing at any scale of geographical zoning.

  12. Merging high resolution geophysical and geochemical surveys to reduce exploration risk at glass buttes, Oregon

    Energy Technology Data Exchange (ETDEWEB)

    Walsh, Patrick [Ormat Nevada, Inc., Reno, NV (United States); Fercho, Steven [Ormat Nevada, Inc., Reno, NV (United States); Perkin, Doug [Ormat Nevada, Inc., Reno, NV (United States); Martini, Brigette [Corescan Inc., Ascot (Australia); Boshmann, Darrick [Oregon State Univ., Corvallis, OR (United States)

    2015-06-01

    The engineering and studies phase of the Glass Buttes project was aimed at reducing risk during the early stages of geothermal project development. The project’s inclusion of high resolution geophysical and geochemical surveys allowed Ormat to evaluate the value of these surveys both independently and in combination to quantify the most valuable course of action for exploration in an area where structure, permeability, and temperature are the most pressing questions. The sizes of the thermal anomalies at Glass Buttes are unusually large. Over the course of Phase I Ormat acquired high resolution LIDAR data to accurately map fault manifestations at the surface and collected detailed gravity and aeromagnetic surveys to map subsurface structural features. In addition, Ormat collected airborne hyperspectral data to assist with mapping the rock petrology and mineral alteration assemblages along Glass Buttes faults and magnetotelluric (MT) survey to try to better constrain the structures at depth. Direct and indirect identification of alteration assemblages reveal not only the geochemical character and temperature of the causative hydrothermal fluids but can also constrain areas of upflow along specific fault segments. All five datasets were merged along with subsurface lithologies and temperatures to predict the most likely locations for high permeability and hot fluids. The Glass Buttes temperature anomalies include 2 areas, totaling 60 km2 (23 mi2) of measured temperature gradients over 165° C/km (10° F/100ft). The Midnight Point temperature anomaly includes the Strat-1 well with 90°C (194 °F) at 603 m (1981 ft) with a 164 °C/km (10°F/100ft) temperature gradient at bottom hole and the GB-18 well with 71°C (160 °F) at 396 m (1300 ft) with a 182°C/km (11°F/100ft) gradient. The primary area of alteration and elevated temperature occurs near major fault intersections associated with Brothers Fault Zone and Basin and Range systems. Evidence for faulting is

  13. Geophysical and geochemical characterisation of groundwater resources in Western Zambia

    DEFF Research Database (Denmark)

    Chongo, Mkhuzo; Banda, Kawawa Eddy; Bauer-Gottwein, Peter

    Zambia’s rural water supply system depends on groundwater resources to a large extent. However, groundwater resources are variable in both quantity and quality across the country and a national groundwater resources assessment and mapping program is presently not in place. In the Machile area...... in South-Western Zambia, groundwater quality problems are particularly acute. Saline groundwater occurrence is widespread and affects rural water supply, which is mainly based on shallow groundwater abstraction using hand pumps. This study has mapped groundwater quality variations in the Machile area using...... both ground-based and airborne geophysical methods as well as extensive water quality sampling. The occurrence of saline groundwater follows a clear spatial pattern and appears to be related to the palaeo Lake Makgadikgadi, whose northernmost extension reached into the Machile area. Because the lake...

  14. Comprehensive geophysical and geochemical method and prognosis criteria for the exploration of unconformity type uranium deposit in Russia

    International Nuclear Information System (INIS)

    Li Mao; Chen Zuyi

    2007-01-01

    According to the transcripts of the lectures by Russian experts during the investigation and training in Russia, the comprehensive geophysical and geochemical method and the prognosis criteria of Russia's unconformity type uranium deposit exploration are introduced in the paper. (authors)

  15. An integrated geophysical and geochemical exploration of critical zone weathering on opposing montane hillslope

    Science.gov (United States)

    Singha, K.; Navarre-Sitchler, A.; Bandler, A.; Pommer, R. E.; Novitsky, C. G.; Holbrook, S.; Moore, J.

    2017-12-01

    Quantifying coupled geochemical and hydrological properties and processes that operate in the critical zone is key to predicting rock weathering and subsequent transmission and storage of water in the shallow subsurface. Geophysical data have the potential to elucidate geochemical and hydrologic processes across landscapes over large spatial scales that are difficult to achieve with point measurements alone. Here, we explore the connections between weathering and fracturing, as measured from integrated geochemical and geophysical borehole data and seismic velocities on north- and south-facing aspects within one watershed in the Boulder Creek Critical Zone Observatory. We drilled eight boreholes up to 13 m deep on north- and south-facing aspects within Upper Gordon Gulch, and surface seismic refraction data were collected near these wells to explore depths of regolith and bedrock, as well as anisotropic characteristics of the subsurface material due to fracturing. Optical televiewer data were collected in these wells to infer the dominant direction of fracturing and fracture density in the near surface to corroborate with the seismic data. Geochemical samples were collected from four of these wells and a series of shallow soil pits for bulk chemistry, clay fraction, and exchangeable cation concentrations to identify depths of chemically altered saprolite. Seismic data show that depth to unweathered bedrock, as defined by p-wave seismic velocity, is slightly thicker on the north-facing slopes. Geochemical data suggest that the depth to the base of saprolite ranges from 3-5 m, consistent with a p-wave velocity value of 1200 m/s. Based on magnitude and anisotropy of p-wave velocities together with optical televiewer data, regolith on north-facing slopes is thought to be more fractured than south-facing slopes, while geochemical data indicate that position on the landscape is another important characteristic in determining depths of weathering. We explore the importance

  16. pplication of Fractal Technique for Analysis of Geophysical - Geochemical Databases in Tekieh Pb-Zn Ore Deposit (SE of Arak

    Directory of Open Access Journals (Sweden)

    Seyed Reza Mehrnia

    2017-02-01

    calculated based on measuring the fractal dimensional variations in the recursive patterns (Mehrnia, 2013. In practice, the Area-Concentration equations (Mandelbrot, 2005 were applied in resistivity, induction polarization, Pb and Zn datasets for achieving the nonlinear relationships in anomalous regions which were characterized by increasing in regression coefficients with more spatial correlation of the variable than linear statistics (Mehrnia, 2013. Results and Discussion This research showed that both linear and nonlinear statistics are able to estimate the spatial association of geochemical anomalies with geophysical variables. A meaningful increase in the regression coefficient was also revealed after measuring the self-similar peculiarities of concentration values on gridded plots (Salehi, 2004; Torkashvand et al., 2009. From the fractal point of view, Pb ore-minerals have been deposited in the western sub-region, while Zn mineralization seems to be extended in the depth of eastern alterations. Also a predictable geochemical zonation can be considered in the western target (meaningful Pb anomalies that is more patterned than the eastern halos according to geological observations (Momenzadeh and Ziseman, 1981 and mineralogical evidences (Salehi, 2004. An increase in Supra ore/Sub ore proportional content was measured in the western sub-region which indicated more reliable potential of Pb mineralization (Galena as a particular indication of sulfide-rich minerals than the same phases of ore forming processes in the eastern sub-region, although the content of Pb-ores rapidly decreases in the eastern target and is replaced by Zn minerals (Sphalerite as particular indication of sulfide-rich mineralization. Because power law relationships are significant in both geochemical and geophysical anomalies (Mehrnia, 2013 a detailed program including borehole geophysics and litho-geochemical land-surveys should be considered in the prospected regions. Therefore, upcoming phases

  17. Geochemical and geophysical monitoring activities in Campo de Calatrava Volcanic Field (Spain)

    Science.gov (United States)

    Luengo-Oroz, Natividad; Villasante-Marcos, Víctor; López-Díaz, Rubén; Calvo, Marta; Albert, Helena; Domínguez Cerdeña, Itahiza

    2017-04-01

    The Campo de Calatrava Volcanic Field (CCVF) or Spanish Central Volcanic Zone is located in central continental Spain (Ciudad Real province) and covers about 5000 km2. It includes around 240 eruptive centers, mainly monogenetic basaltic cones but also explosive maar structures. According to K-Ar geochronology, its main activity phase occurred during Pliocene and Pleistocene epochs (between 5 and 1.7 Ma) and involved alkaline to ultraalkaline magmas, although an older ultrapotassic phase is dated around 8.7-6.4 Ma. However, some recent works have proposed Holocene ages for some of the volcanic products, opening the possibility of considering the CCVF "active" according to international standards. Responding to this situation, the Instituto Geográfico Nacional (IGN) has initiated geochemical and geophysical monitoring activities in the CCVF. Here, we describe these ongoing efforts and we report results about groundwater geochemistry at several natural highly-gaseous springs in the area (hervideros), as well as soil temperature, CO2 diffuse flux from the soil and electrical self-potential data mapped on a small degassing structure called La Sima. In order to analyze microseismicity or any seismic anomaly in the CCVF, a seismic station has also been installed close to this degassing structure. Physicochemical parameters (temperature, pH, Eh and electric conductivity) were measured in situ in four springs and samples were taken in order to analyze major ions and trace elements. Total composition of dissolved gases and helium isotopic ratios were also determined. To complete soil temperature, self-potential and gas prospections performed in La Sima, soil gases were sampled at the bottom of the structure at a depth of 20 cm. Analysis of the total gas composition found 957400 ppm of CO2. Low values of O2 and N2 were also detected (5600 and 24800 ppm respectively).

  18. Development of data processing system for regional geophysical and geochemical exploration of sandstone-hosted uranium deposits based on ArcGIS Engine

    International Nuclear Information System (INIS)

    Han Shaoyang; Ke Dan; Hou Huiqun; Hu Shuiqing

    2010-01-01

    According to the data processing need of geophysical and geochemical exploration of sandstone-hosted uranium deposits, the function design of the regional geophysical and geochemical data processing system is completed in the paper. The geophysical and geochemical data processing software with powerful functions is also developed based on ArcGIS Engine which remedies the shortage of GIS software for performing the geophysical and geochemical data processing. The development technique route of system software and key techniques are introduced, and the development processes of system software are showed through some development examples. Application practices indicate that the interface of developed system software with friendly interface and utility functions, may quickly perform the data processing of regional geophysical and geochemical exploration and provide the helpful deep information for predicting metallogenic prospective areas of sandstone-hosted uranium deposits. The system software is of a great application foreground. (authors)

  19. Geophysical and geochemical models of the Earth's shields and rift zones

    International Nuclear Information System (INIS)

    Chung, D.H.

    1977-01-01

    This report summarizes a collection of, synthesis of, and speculation on the geophysical and geochemical models of the earth's stable shields and rift zones. Two basic crustal types, continental and oceanic, and two basic mantle types, stable and unstable, are described. It is pointed out that both the crust and upper mantle play a strongly interactive role with surface geological phenomena ranging from the occurrence of mountains, ocean trenches, oceanic and continental rifts to geographic distributions of earthquakes, faults, and volcanoes. On the composition of the mantle, there is little doubt regarding the view that olivine constitutes a major fraction of the mineralogy of the earth's upper mantle. Studies are suggested to simulate the elasticity and composition of the earth's lower crust and upper mantle

  20. Geological, geochemical, and geophysical survey of the geothermal resources at Hot Springs Bay Valley, Akutan Island, Alaska

    Energy Technology Data Exchange (ETDEWEB)

    Motyka, R.J.; Wescott, E.M.; Turner, D.L.; Swanson, S.E.; Romick, J.D.; Moorman, M.A.; Poreda, R.J.; Witte, W.; Petzinger, B.; Allely, R.D.

    1985-01-01

    An extensive survey was conducted of the geothermal resource potential of Hot Springs Bay Valley on Akutan Island. A topographic base map was constructed, geologic mapping, geophysical and geochemical surveys were conducted, and the thermal waters and fumarolic gases were analyzed for major and minor element species and stable isotope composition. (ACR)

  1. Geochemical mapping in polluted floodplains using handheld XRF, geophysical imaging, and geostatistics

    Science.gov (United States)

    Hošek, Michal; Matys Grygar, Tomáš; Popelka, Jan; Kiss, Timea; Elznicová, Jitka; Faměra, Martin

    2017-04-01

    In the recent years researchers have enjoyed noticeable improvements of portable analytical and geophysical methods, which allow studying floodplain architecture and deciphering pollutant distribution more easily than ever before. Our area of interest was floodplain of the Ploučnice River, particularly a pollution hotspot in Boreček, severely impacted by U mining between the 1970s and late 1980s, in particular a "radioactive flood" in 1981. In the area, we used hand drill coring and in situ (field) analysis of so acquired sediments by handheld X-ray fluorescence spectrometer (XRF), which gave us information about depth profiles of pollutants (Ba, U, Zn) and the Al/Si and Zr/Rb ratios, i.e., proxies for sediment lithology. We found that spatial distribution of pollutants (control by depth and position in the floodplain) is apparently complex and discontinuous. In some places, contamination is buried by a couple decimetres of less polluted sediments, while in other places the peak pollution is near surface, apparently without a straightforward connection with the surface topography and the distance to the river channel. We thus examined the floodplain architecture, the internal structure of the floodplain using two geophysical methods. First of them, dipole electromagnetic profiling (DEMP, also denoted EMP, MP, or Slingram) quickly acquires average electric resistivity in top strata in selected areas, which was actually top 3 m with our particular instrument. Second, electric resistivity tomography (ERT) produces much more detailed information on resistivity with depth resolution of ca 0.5 m to the depth of ca 5 m in selected lines. ERT thus allows identifying boundaries of electric resistivity domains (sediment bodies) and DEMP their spatial distribution. Based on the obtained data, we divided the floodplain to five segments with specific topography, pollution characteristics, and electric resistivity. We suppose that those segments are lithogenetic floodplain

  2. Arsenic Groundwater Contamination in Bengal: a Coupled Geochemical and Geophysical Study

    Science.gov (United States)

    Charlet, L.; Ansari, A. A.; Dietrich, M.; Latscha, A.; LeBeux, A.; Chatterjee, D.; Mallik, S. B.

    2001-05-01

    Arsenic contamination in drinking water is a problem of great concern in Ganges delta region, and could be one of the largest natural calamity in the world. In the present study, a contamination plume located in the Lalpur area (Chakdaha Block, Nadia District, West Bengal, India) was studied. A coupled geochemical and geophysical approach was employed to understand the mechanism of arsenic mobilisation from the sediments to groundwater, as a first step towards a global explanation of the phenomenon for other contaminated areas in the Ganges delta. The groundwater As concentration, in the 10 km x 10 km studied area, ranges from 10 to 500 ppb. In situ chemical speciation of arsenic was carried out and various geochemical parameters were measured in representative contaminated wells to interpret the mobilization mechanism in terms of redox kinetics. Through geophysical investigations, subsurface lithology, sediment depositional and geomorphological characteristics were determined and correlated with the arsenic contamination processes. From a geomorphological viewpoint, the contaminated area is located in an abandoned paleochannel of the Hooghly river, interpreted as the active site of deposition of fine sediments which were preserved as clay pockets at certain depths. These clay pockets are rich in organic matter, which may be the driving force for redox potential change and thus, may have driven the mobilisation of arsenic in groundwater. The clay pockets rich in organic matter presumably represent the major reservoir where arsenic is sitting and getting released due to redox mechanism. They are sampled at present. A piezometric depression cone characterized by a radial groundwater flow is located underneath the highly populated Lalpur area. The arsenic plume appears to migrate from the Hooghly river towards the cone of depression following the water flowpath, and this shall be verified in forthcoming field campaigns. As (III) constitutes 42 % of the total As

  3. Geophysical Monitoring of Coupled Microbial and Geochemical Processes During Stimulated Subsurface Bioremediation

    International Nuclear Information System (INIS)

    Williams, Kenneth H.; Kemna, Andreas; Wilkins, Michael J.; Druhan, Jennifer L.; Arntzen, Evan V.; N'Guessan, A. Lucie; Long, Philip E.; Hubbard, Susan S.; Banfield, Jillian F.

    2009-01-01

    Understanding how microorganisms alter their physical and chemical environment during bioremediation is hindered by our inability to resolve subsurface microbial activity with high spatial resolution. Here we demonstrate the use of a minimally invasive geophysical technique to monitor stimulated microbial activity during acetate amendment in an aquifer near Rifle, Colorado. During electrical induced polarization (IP) measurements, spatiotemporal variations in the phase response between imposed electric current and the resultant electric field correlated with changes in groundwater geochemistry accompanying stimulated iron and sulfate reduction and sulfide mineral precipitation. The magnitude of the phase response varied with measurement frequency (0.125 and 1 Hz) and was dependent upon the dominant metabolic process. The spectral effect was corroborated using a biostimulated column experiment containing Rifle sediments and groundwater. Fluids and sediments recovered from regions exhibiting an anomalous phase response were enriched in Fe(II), dissolved sulfide, and cell-associated FeS nanoparticles. The accumulation of mineral precipitates and electroactive ions altered the ability of pore fluids to conduct electrical charge, accounting for the anomalous IP response and revealing the usefulness of multifrequency IP measurements for monitoring mineralogical and geochemical changes accompanying stimulated subsurface bioremediation

  4. An integrated geological, geochemical, and geophysical investigation of uranium metallogenesis in selected granitic plutons of the Miramichi Anticlinorium, New Brunswick

    International Nuclear Information System (INIS)

    Hassan, H.H.; McAllister, A.L.

    1992-01-01

    Integrated geological, geochemical, and geophysical data for the post-tectonic granitic rocks of the North Pole, Burnthill, Dungarvon, Trout Brook, and Rocky Brook plutons and surrounding areas were examined to assess their potential for uranium mineralization. Geological, geochemical, and geophysical criteria that are thought to be useful guides for uranium exploration were also established for the host granites. The granitic plutons were emplaced discordantly, late in the tectonomagmatic sequence and at shallow depths within the metasedimentary rocks of the Miramichi Anticlinorium. Geochemically, the host granites are highly evolved (Si0 2 > 75 wt. %), peraluminous and have strong similarities with ilmenite-series 'S-type' and 'A-type' granitoids. Uranium occurrences are spatially and perhaps temporally associated with late-phase differentiates of the plutons where elevated levels of other lithophile elements such as Sn, W, Mo, and F were also detected. Geophysically, the granitic plutons are associated with distinctively high aeroradiometric eU, eTh, and K anomalies that coincide with strong negative Bouguer anomalies and low magnetic values. Conceptual models involving magmatic and hydrothermal processes have been adopted to explain the concentration of uranium and associated metals in the granitic plutons

  5. Joint Inversion of Geochemical Data and Geophysical Logs for Lithology Identification in CCSD Main Hole

    Science.gov (United States)

    Deng, Chengxiang; Pan, Heping; Luo, Miao

    2017-12-01

    The Chinese Continental Scientific Drilling (CCSD) main hole is located in the Sulu ultrahigh-pressure metamorphic (UHPM) belt, providing significant opportunities for studying the metamorphic strata structure, kinetics process and tectonic evolution. Lithology identification is the primary and crucial stage for above geoscientific researches. To release the burden of log analyst and improve the efficiency of lithology interpretation, many algorithms have been developed to automate the process of lithology prediction. While traditional statistical techniques, such as discriminant analysis and K-nearest neighbors classifier, are incompetent in extracting nonlinear features of metamorphic rocks from complex geophysical log data; artificial intelligence algorithms are capable of solving nonlinear problems, but most of the algorithms suffer from tuning parameters to be global optimum to establish model rather than local optimum, and also encounter challenges in making the balance between training accuracy and generalization ability. Optimization methods have been applied extensively in the inversion of reservoir parameters of sedimentary formations using well logs. However, it is difficult to obtain accurate solution from the logging response equations of optimization method because of the strong overlapping of nonstationary log signals when applied in metamorphic formations. As oxide contents of each kinds of metamorphic rocks are relatively less overlapping, this study explores an approach, set in a metamorphic formation model and using the Broyden Fletcher Goldfarb Shanno (BFGS) optimization algorithm to identify lithology from oxide data. We first incorporate 11 geophysical logs and lab-collected geochemical data of 47 core samples to construct oxide profile of CCSD main hole by using backwards stepwise multiple regression method, which eliminates irrelevant input logs step by step for higher statistical significance and accuracy. Then we establish oxide response

  6. A geochemical and geophysical reappraisal to the significance of the recent unrest at Campi Flegrei caldera (Southern Italy)

    Science.gov (United States)

    Moretti, Roberto; De Natale, Giuseppe; Troise, Claudia

    2017-04-01

    Volcanic unrest at calderas involve complex interaction between magma, hydrothermal fluids and crustal stress and strain. Campi Flegrei caldera (CFc), located in the Naples (Italy) area and characterised by the highest volcanic risk on Earth for the extreme urbanisation, undergoes unrest phenomena involving several meters of uplift and intense shallow micro-seismicity since several decades. Despite unrest episodes display in the last decade only moderate ground deformation and seismicity, current interpretations of geochemical data point to a highly pressurized hydrothermal system. We show that at CFc, the usual assumption of vapour-liquid coexistence in the fumarole plumes leads to largely overestimated hydrothermal pressures and, accordingly, interpretations of elevated unrest. By relaxing unconstrained geochemical assumptions, we infer an alternative model yielding better agreement between geophysical and geochemical observations. The model reconciles discrepancies between what observed 1) for two decades since the 1982-84 large unrest, when shallow magma was supplying heat and fluids to the hydrothermal system, and 2) in the last decade. Compared to the 1980's unrest, the post-2005 phenomena are characterized by much lower aquifers overpressure and magmatic involvement, as indicated by geophysical data and despite large changes in geochemical indicators. Our interpretation points out a model in which shallow sills, intruded during 1969-1984, have completely cooled, so that fumarole emissions are affected now by deeper, CO2-richer, magmatic gases producing a relatively modest heating and overpressure of the hydrothermal system. Our results do have important implications on the short-term eruption hazard assessment and on the best strategies for monitoring and interpreting geochemical data.

  7. Geological, geochemical, and geophysical studies by the U.S. Geological Survey in Big Bend National Park, Texas

    Science.gov (United States)

    Page, W.R.; Turner, K.J.; Bohannon, R.G.; Berry, M.E.; Williams, V.S.; Miggins, D.P.; Ren, M.; Anthony, E.Y.; Morgan, L.A.; Shanks, P.W.C.; Gray, J. E.; Theodorakos, P.M.; Krabbenhoft, D. P.; Manning, A.H.; Gemery-Hill, P. A.; Hellgren, E.C.; Stricker, C.A.; Onorato, D.P.; Finn, C.A.; Anderson, E.; Gray, J. E.; Page, W.R.

    2008-01-01

    Big Bend National Park (BBNP), Tex., covers 801,163 acres (3,242 km2) and was established in 1944 through a transfer of land from the State of Texas to the United States. The park is located along a 118-mile (190-km) stretch of the Rio Grande at the United States-Mexico border. The park is in the Chihuahuan Desert, an ecosystem with high mountain ranges and basin environments containing a wide variety of native plants and animals, including more than 1,200 species of plants, more than 450 species of birds, 56 species of reptiles, and 75 species of mammals. In addition, the geology of BBNP, which varies widely from high mountains to broad open lowland basins, also enhances the beauty of the park. For example, the park contains the Chisos Mountains, which are dominantly composed of thick outcrops of Tertiary extrusive and intrusive igneous rocks that reach an altitude of 7,832 ft (2,387 m) and are considered the southernmost mountain range in the United States. Geologic features in BBNP provide opportunities to study the formation of mineral deposits and their environmental effects; the origin and formation of sedimentary and igneous rocks; Paleozoic, Mesozoic, and Cenozoic fossils; and surface and ground water resources. Mineral deposits in and around BBNP contain commodities such as mercury (Hg), uranium (U), and fluorine (F), but of these, the only significant mining has been for Hg. Because of the biological and geological diversity of BBNP, more than 350,000 tourists visit the park each year. The U.S. Geological Survey (USGS) has been investigating a number of broad and diverse geologic, geochemical, and geophysical topics in BBNP to provide fundamental information needed by the National Park Service (NPS) to address resource management goals in this park. Scientists from the USGS Mineral Resources and National Cooperative Geologic Mapping Programs have been working cooperatively with the NPS and several universities on several research studies within BBNP

  8. Application of the geophysical and geochemical methods to the research for uranium

    International Nuclear Information System (INIS)

    Gangloff, A.M.; Collin, C.R.; Grimbert, A.; Sanselme, H.

    1958-01-01

    Since 1954, at the Commissariat a l'energie atomique, geophysics and geochemistry have been added to routine geological surveying and radiometric observations. Geophysical prospecting reveals the tectonic structures linked with French uranium deposits and gives an idea of favorable zones. Geochemistry adds to the geophysical indirect methods further details on the distribution of uranium traces in the soils. This method is direct and specific. Uranium assay in waters and alluvial deposits find its use in preliminary exploration. (author) [fr

  9. Geophysical and geochemical regional evaluation and geophysical model for uranium exploration in the western part of Yanliao region

    International Nuclear Information System (INIS)

    Liu Tengyao; Cui Huanmin; Chen Guoliang; Zhai Yugui

    1992-01-01

    The western part of Yanliao region is an important uranium metallogenic region. This paper summarizes the regional geophysical model for uranium exploration composed of prediction model for favourable area of mineralization and evaluation model for anomalies on the basis of aeromagnetic and aeroradiometric data interpretation and analysis of the data from carborane and ground gamma spectrometric survey, high accurate magnetic survey, VLF survey and α-collected film survey in mult-displiary research work. The prospective prediction for uranium metallogenesis in this region was also conducted

  10. Geochemical and Geophysical Characteristics of the Balud Ophiolitic Complex (BOC, Masbate Island, Philippines: Implications for its Generation, Evolution and Emplacement

    Directory of Open Access Journals (Sweden)

    Pearlyn C. Manalo

    2015-01-01

    Full Text Available This paper presents the first field, geochemical and geophysical information on the recently recognized Early Cretaceous Balud Ophiolitic Complex (BOC in the island of Masbate in the Central Philippines. Mapping of the western limb of the island revealed that only the upper crustal section of the BOC is exposed in this area. Geochemically, the pillow basalts are characterized by transitional mid-oceanic ridge basalt-island arc tholeiitic compositions. Gravity surveys yielded low Bouguer anomaly values that are consistent with the highly dismembered nature of the BOC. Short wavelength, high amplitude magnetic anomalies registered across the study area are attributed to shallow magnetic sources. This is taken to support the model that the ophiolitic complex occurs as thin crustal slivers that are not deeply-rooted in the mantle. Comparing BOC with other ophiolites in the Central Philippines, such as those in the islands of Sibuyan, Leyte and Bohol, suggests the possibility of a common or contiguous source for similarly-aged and geochemically composed crust-mantle sequences in the region.

  11. Application of Fractal Technique for Analysis of Geophysical - Geochemical Databases in Tekieh Pb-Zn Ore Deposit (SE of Arak)

    International Nuclear Information System (INIS)

    Mehrnia, S.R.

    2017-01-01

    In this research, two statistical techniques that consist of classical and fractal equations (Mandelbrot, 2005) were applied in geochemical (Torkashvand et al., 2009) and geophysical (Jafari, 2007) databases for obtaining the linear and nonlinear distributions of geochemical elements (Tekieh Pb-Zn content) in association with resistivity variations and induction polarization measurements (Calagari, 2010). According to linear statistical techniques (Torkashvand et al., 2009), the main central parameters such as mean, median and mode in addition to variances and standard deviations as distribution tendencies could be used for obtaining the regression coefficients of the databases. However, in fractal statistics, a reliable regression between geo electrical - geochemical anomalies should be calculated based on measuring the fractal dimensional variations in the recursive patterns (Mehrnia, 2013). In practice, the Area-Concentration equations (Mandelbrot, 2005) were applied in resistivity, induction polarization, Pb and Zn datasets for achieving the nonlinear relationships in anomalous regions which were characterized by increasing in regression coefficients with more spatial correlation of the variable than linear statistics (Mehrnia, 2013).

  12. Geophysical and geochemical processing of data from the Santa Terezinha de Goias region, Brazil

    International Nuclear Information System (INIS)

    Calle, Carlos Humberto Tapia; Pires, A.C.B.

    1995-01-01

    The paper presents a few data processing techniques used with geophysical and geometry data from Santa Terezinha de Goias. Airborne gamma ray spectrometry and magnetometry were conduced in the area during the Brazil Canada Geophysical Project. Black and white and color images produced using available procedures resulted in new interpretation for the geological mapping. Guidelines for emerald exploration in the area are suggested from images and anomalous potassium map. (author). 14 refs., 5 figs

  13. Combined geophysical, geochemical and geological investigations of geothermal reservoir characteristics in Lower Saxony, Germany

    Science.gov (United States)

    Hahne, B.; Thomas, R.

    2012-04-01

    The North German basin provides a significant geothermal potential, although temperature gradients are moderate. However, deep drilling up to several thousand meters is required to reach temperatures high enough for efficient generation of geothermal heat and electric power. In these depths we have not much information yet about relevant physical properties like porosity or permeability of the rock formations. Therefore the costs of developing a geothermal reservoir and the risk of missing the optimum drilling location are high. The collaborative research association "Geothermal Energy and High Performance Drilling" (gebo) unites several universities and research institutes in Lower Saxony, Germany. It aims at a significant increase of economic efficiency by introducing innovative technology and high tech materials resisting temperatures up to 200 °C in the drilling process. Furthermore, a better understanding of the geothermal reservoir is essential. gebo is structured into four main fields: Drilling Technology, Materials, Technical Systems and Geosystem. Here, we show the combined work of the Geosystem group, which focuses on the exploration of geological fault zones as a potential geothermal reservoir as well as on modeling the stress field, heat transport, coupled thermo-hydro-mechanical processes, geochemical interactions and prediction of the long-term behavior of the reservoir. First results include combined seismic and geoelectric images of the Leinetalgraben fault system, a comparison of seismic images from P- and S-wave measurements, mechanical properties of North German rocks from field and laboratory measurements as well as from drill cores, seismological characterization of stimulated reservoirs, a thermodynamic "gebo" database for modeling hydrogeochemical processes in North German formation waters with high salinity and at high temperatures, stress models for specific sites in northern Germany, and modeling results of permeability and heat transport

  14. Geochemical mapping in polluted floodplains using handheld XRF, geophysical imaging, and geostatistics

    Czech Academy of Sciences Publication Activity Database

    Hošek, Michal; Matys Grygar, Tomáš; Popelka, J.; Kiss, T.; Elznicová, J.; Faměra, Martin

    2017-01-01

    Roč. 19, APR (2017) ISSN 1607-7962. [EGU General Assembly 2017. 23.04.2017-28.04.2017, Vienna] Institutional support: RVO:61388980 Keywords : Dipole electromagneting profilling * electric resistivity tomography * floodplain contamination * geochemical mapping Subject RIV: DD - Geochemistry http://meetingorganizer.copernicus.org/EGU2017/EGU2017-3573-3.pdf

  15. Geophysics

    CERN Document Server

    Bolt, Bruce

    1973-01-01

    Methods in Computational Physics, Volume 13: Geophysics is a 10-chapter text that focuses with the theoretical solid-earth geophysics. This volume specifically covers the general topics of terrestrial magnetism and electricity, the Earth's gravity field, tidal deformations, dynamics of global spin, spin processing, and convective models for the deep interior. This volume surveys first the construction of mathematical models, such as the representation of the geomagnetic field by assuming arrangements of multipole sources in the core and the fast computer evaluation of two- and three-dimensiona

  16. Shale gas characterization based on geochemical and geophysical analysis: Case study of Brown shale, Pematang formation, Central Sumatra Basin

    Science.gov (United States)

    Haris, A.; Nastria, N.; Soebandrio, D.; Riyanto, A.

    2017-07-01

    Geochemical and geophysical analyses of shale gas have been carried out in Brown Shale, Middle Pematang Formation, Central Sumatra Basin. The paper is aimed at delineating the sweet spot distribution of potential shale gas reservoir, which is based on Total Organic Carbon (TOC), Maturity level data, and combined with TOC modeling that refers to Passey and Regression Multi Linear method. We used 4 well data, side wall core and 3D pre-stack seismic data. Our analysis of geochemical properties is based on well log and core data and its distribution are constrained by a framework of 3D seismic data, which is transformed into acoustic impedance. Further, the sweet spot of organic-rich shale is delineated by mapping TOC, which is extracted from inverted acoustic impedance. Our experiment analysis shows that organic materials contained in the formation of Middle Pematang Brown Shale members have TOC range from 0.15 to 2.71 wt.%, which is classified in the quality of poor to very good. In addition, the maturity level of organic material is ranging from 373°C to 432°C, which is indicated by vitrinite reflectance (Ro) of 0.58. In term of kerogen type, this Brown shale formation is categorized as kerogen type of II I III, which has the potential to generate a mixture of gasIoil on the environment.

  17. Constraining Lateral Evolution of Magmatic Behavior in North Tanzania from Geophysical and Geochemical Analyses

    Science.gov (United States)

    Gautier, S.; Tiberi, C.; Parat, F.; Baudouin, C.

    2016-12-01

    In the framework of CRAFTI and CoLiBrEA experiments in 2013, we proceeded to both seismic and geochemical studies along an EW profile through the North Tanzania Divergence. The data were collected along a line starting at the Ngorongoro volcanic area, ending at Kitumbeine edifice and crossing the rift valley. Recent seismological studies show lateral and depth variations for both velocity and Vp/Vs ratio within this area, particularly a change of Moho depth between the western and central parts of the rift. These two zones also exhibit diverse geochemical signatures that involve different magma storage (depth of reservoir, magma volume) and ascent as well as higher partial melts content for the western part. We take advantage of the recent and precise 3D lithospheric velocity models and receiver functions in this area to compare the structure and nature of Ngorongoro area and rift valley. We first compute ray path and establish regional coherency maps between piercing points, Vp/Vs ratio and tomographic images. Second, those results are compared with the composition of magma at depth obtained from a petrophysical and geochemical analysis of lava samples. We will discuss those results in terms of magmatic processes, and how they interact with the rifting in a cratonic lithosphere.

  18. Preclosure monitoring and performance confirmation at Yucca Mountain: Applicability of geophysical, geohydrological, and geochemical methods

    International Nuclear Information System (INIS)

    Tsang, C.F.

    1989-06-01

    The present paper presents considerations on studies that would be required for preclosure monitoring and performance confirmation of a nuclear waste geologic repository in an unsaturated zone. The critical parameters that should be monitored are reviewed and two scales of measurement relevant to monitoring activities, room scale and repository scale, are taken as a framework for investigation. A number of monitoring methods based on geophysics, geohydrology, and geochemistry are briefly summarized for their potential usefulness for preclosure monitoring and performance confirmation of the geologic repository. Particular emphasis is given to measurement of the spatial distribution of parameters in contrast to single-point measurements of quantities. 12 refs., 1 fig., 1 tab

  19. A general framework of TOPSIS method for integration of airborne geophysics, satellite imagery, geochemical and geological data

    Science.gov (United States)

    Abedi, Maysam; Norouzi, Gholam-Hossain

    2016-04-01

    This work presents the promising application of three variants of TOPSIS method (namely the conventional, adjusted and modified versions) as a straightforward knowledge-driven technique in multi criteria decision making processes for data fusion of a broad exploratory geo-dataset in mineral potential/prospectivity mapping. The method is implemented to airborne geophysical data (e.g. potassium radiometry, aeromagnetic and frequency domain electromagnetic data), surface geological layers (fault and host rock zones), extracted alteration layers from remote sensing satellite imagery data, and five evidential attributes from stream sediment geochemical data. The central Iranian volcanic-sedimentary belt in Kerman province at the SE of Iran that is embedded in the Urumieh-Dokhtar Magmatic Assemblage arc (UDMA) is chosen to integrate broad evidential layers in the region of prospect. The studied area has high potential of ore mineral occurrences especially porphyry copper/molybdenum and the generated mineral potential maps aim to outline new prospect zones for further investigation in future. Two evidential layers of the downward continued aeromagnetic data and its analytic signal filter are prepared to be incorporated in fusion process as geophysical plausible footprints of the porphyry type mineralization. The low values of the apparent resistivity layer calculated from the airborne frequency domain electromagnetic data are also used as an electrical criterion in this investigation. Four remote sensing evidential layers of argillic, phyllic, propylitic and hydroxyl alterations were extracted from ASTER images in order to map the altered areas associated with porphyry type deposits, whilst the ETM+ satellite imagery data were used as well to map iron oxide layer. Since potassium alteration is generally the mainstay of porphyry ore mineralization, the airborne potassium radiometry data was used. The geochemical layers of Cu/B/Pb/Zn elements and the first component of PCA

  20. Geophysical and geochemical constraints on the geodynamic origin of the Vrancea Seismogenic Zone Romania

    Science.gov (United States)

    Fillerup, Melvin A.

    The Vrancea Seismogenic Zone (VSZ) of Romania is a steeply NW-dipping volume (30 x 70 x 200 km) of intermediate-depth seismicity in the upper mantle beneath the bend zone of the Eastern Carpathians. The majority of tectonic models lean heavily on subduction processes to explain the Vrancea mantle seismicity and the presence of a Miocene age calc-alkaline volcanic arc in the East Carpathian hinterland. However, recent deep seismic reflection data collected over the Eastern Carpathian bend zone image an orogen lacking (1) a crustal root and (2) dipping crustal-scale fabrics routinely imaged in modern and ancient subduction zones. The DRACULA I and DACIA-PLAN deep seismic reflection profiles show that the East Carpathian orogen is supported by crust only 30-33 km thick while the Focsani basin (foreland) and Transylvanian basin (hinterland) crust is 42 km and 46 km thick respectively. Here the VSZ is interpreted as the former Eastern Carpathian orogenic root which was removed as a result of continental lithospheric delamination and is seismically foundering beneath the East Carpathian bend zone. Because large volumes of calc-alkaline volcanism are typically associated with subduction settings existing geochemical analyses from the Calimani, Gurghiu, and Harghita Mountains (CGH) have been reinterpreted in light of the seismic data which does not advocate the subduction of oceanic lithosphere. CGH rocks exhibit a compositional range from basalt to rhyolite, many with high-Mg# (Mg/Mg+Fe > 0.60), high-Sr (>1000 ppm), and elevated delta-O18 values (6-8.7 /) typical of arc lavas, and are consistent with mixing of mantle-derived melts with a crustal component. The 143Nd/144Nd (0.5123-0.5129) and 87Sr/86Sr (0.7040-0.7103) ratios similarly suggest mixing of mantle and crustal end members to obtain the observed isotopic compositions. A new geochemical model is presented whereby delamination initiates a geodynamic process like subduction but with the distinct absence of subducted

  1. Hydrogeological modeling constraints provided by geophysical and geochemical mapping of a chlorinated ethenes plume in northern France

    Science.gov (United States)

    Razafindratsima, Stephen; Guérin, Roger; Bendjoudi, Hocine; de Marsily, Ghislain

    2014-09-01

    A methodological approach is described which combines geophysical and geochemical data to delineate the extent of a chlorinated ethenes plume in northern France; the methodology was used to calibrate a hydrogeological model of the contaminants' migration and degradation. The existence of strong reducing conditions in some parts of the aquifer is first determined by measuring in situ the redox potential and dissolved oxygen, dissolved ferrous iron and chloride concentrations. Electrical resistivity imaging and electromagnetic mapping, using the Slingram method, are then used to determine the shape of the pollutant plume. A decreasing empirical exponential relation between measured chloride concentrations in the water and aquifer electrical resistivity is observed; the resistivity formation factor calculated at a few points also shows a major contribution of chloride concentration in the resistivity of the saturated porous medium. MODFLOW software and MT3D99 first-order parent-daughter chain reaction and the RT3D aerobic-anaerobic model for tetrachloroethene (PCE)/trichloroethene (TCE) dechlorination are finally used for a first attempt at modeling the degradation of the chlorinated ethenes. After calibration, the distribution of the chlorinated ethenes and their degradation products simulated with the model approximately reflects the mean measured values in the observation wells, confirming the data-derived image of the plume.

  2. Targeting of Gold Deposits in Amazonian Exploration Frontiers using Knowledge- and Data-Driven Spatial Modeling of Geophysical, Geochemical, and Geological Data

    Science.gov (United States)

    Magalhães, Lucíola Alves; Souza Filho, Carlos Roberto

    2012-03-01

    This paper reports the application of weights-of-evidence, artificial neural networks, and fuzzy logic spatial modeling techniques to generate prospectivity maps for gold mineralization in the neighborhood of the Amapari Au mine, Brazil. The study area comprises one of the last Brazilian mineral exploration frontiers. The Amapari mine is located in the Maroni-Itaicaiúnas Province, which regionally hosts important gold, iron, manganese, chromite, diamond, bauxite, kaolinite, and cassiterite deposits. The Amapari Au mine is characterized as of the orogenic gold deposit type. The highest gold grades are associated with highly deformed rocks and are concentrated in sulfide-rich veins mainly composed of pyrrhotite. The data used for the generation of gold prospectivity models include aerogeophysical and geological maps as well as the gold content of stream sediment samples. The prospectivity maps provided by these three methods showed that the Amapari mine stands out as an area of high potential for gold mineralization. The prospectivity maps also highlight new targets for gold exploration. These new targets were validated by means of detailed maps of gold geochemical anomalies in soil and by fieldwork. The identified target areas exhibit good spatial coincidence with the main soil geochemical anomalies and prospects, thus demonstrating that the delineation of exploration targets by analysis and integration of indirect datasets in a geographic information system (GIS) is consistent with direct prospecting. Considering that work of this nature has never been developed in the Amazonian region, this is an important example of the applicability and functionality of geophysical data and prospectivity analysis in regions where geologic and metallogenetic information is scarce.

  3. Geochemical and geophysical investigations, and fluid inclusion studies in the exploration area of Zafarghand (Northeast Isfahan, Iran

    Directory of Open Access Journals (Sweden)

    Zahra Alaminia

    2017-11-01

    Full Text Available Introduction Urumieh-Dokhtar Magmatic Arc (UDMA is a good prospective area for Cu, Cu-Mo and Cu-Au deposits (Fig. 1A and B. The Zafarghand district is located in the central part of the UDMA and the northeastern Isfahan. The present study concerns geological observations, alteration investigations, geochemical data and fluid inclusion studies. The purpose of the research is to identify geochemical anomalies and source of metals in this area. Geochemical anomalies for mineralizing elements and element associations were identified by using statistical analysis methods. Additionally, these results together suggest a site for exploration drilling in this study area. Materials and methods We collected 186 samples (rock along multi-cross sections oriented perpendicular to the strike of the South -Ardestan fault (Fig. 2.Trace element concentrations were determined by the ICP-MS technique in Amdel laboratory (Australia. Thin sections and doubly polished sections (100–200 µm thick from quartz veins were prepared from samples collected from the Zafarghand district in the University of Isfahan. Heating and freezing experiments on fluid inclusions were performed as defined (by Goldstein and Reynolds (1994 on a Linkam THM600 stage. Results Igneous rocks in the Zafarghand area are dominated by the Eocene and post Eocene acidic-intermediate rocks that include dacite, rhyodacite and andesite associated with diorite, quartz diorite and microdiorite intrusions. The present investigations indicate that all rocks of the Zafarghand district exhibit a variety of alterations. Hydrothermal alterations include phyllic, potassic, silicification, and argillic with widespread propylitic. The mineralization consists of malachite, azurite, hematite, and goethite, rare amounts of magnetite, pyrite, and chalcopyrite. Numerical traditional statistical analysis techniques have been applied to interpret the geochemical data of the study area. These methods are aimed at

  4. Development of a Model of Geophysical and Geochemical Controls on Abiotic Carbon Cycling on Earth-Like Planets

    Science.gov (United States)

    Neveu, M.; Felton, R.; Domagal-Goldman, S. D.; Desch, S. J.; Arney, G. N.

    2017-12-01

    About 20 Earth-sized planets (0.6-1.6 Earth masses and radii) have now been discovered beyond our solar system [1]. Although such planets are prime targets in the upcoming search for atmospheric biosignatures, their composition, geology, and climate are essentially unconstrained. Yet, developing an understanding of how these factors influence planetary evolution through time and space is essential to establishing abiotic backgrounds against which any deviations can provide evidence for biological activity. To this end, we are building coupled geophysical-geochemical models of abiotic carbon cycling on such planets. Our models are controlled by atmospheric factors such as temperature and composition, and compute interior inputs to atmospheric species. They account for crustal weathering, ocean-atmosphere equilibria, and exchange with the deep interior as a function of planet composition and size (and, eventually, age).Planets in other solar systems differ from the Earth not only in their bulk physical properties, but also likely in their bulk chemical composition [2], which influences key parameters such as the vigor of mantle convection and the near-surface redox state. Therefore, simulating how variations in such parameters affect carbon cycling requires us to simulate the above processes from first principles, rather than by using arbitrary parameterizations derived from observations as is often done with models of carbon cycling on Earth [3] or extrapolations thereof [4]. As a first step, we have developed a kinetic model of crustal weathering using the PHREEQC code [5] and kinetic data from [6]. We will present the ability of such a model to replicate Earth's carbon cycle using, for the time being, parameterizations for surface-interior-atmosphere exchange processes such as volcanism (e.g., [7]).[1] exoplanet.eu, 7/28/2017.[2] Young et al. (2014) Astrobiology 14, 603-626.[3] Lerman & Wu (2008) Kinetics of Global Geochemical Cycles. In Kinetics of Water

  5. Surface geochemical data evaluation and integration with geophysical observations for hydrocarbon prospecting, Tapti graben, Deccan Syneclise, India

    Directory of Open Access Journals (Sweden)

    T. Satish Kumar

    2014-05-01

    Full Text Available The Deccan Syneclise is considered to have significant hydrocarbon potential. However, significant hydrocarbon discoveries, particularly for Mesozoic sequences, have not been established through conventional exploration due to the thick basalt cover over Mesozoic sedimentary rocks. In this study, near-surface geochemical data are used to understand the petroleum system and also investigate type of source for hydrocarbons generation of the study area. Soil samples were collected from favorable areas identified by integrated geophysical studies. The compositional and isotopic signatures of adsorbed gaseous hydrocarbons (methane through butane were used as surface indicators of petroleum micro-seepages. An analysis of 75 near-surface soil-gas samples was carried out for light hydrocarbons (C1–C4 and their carbon isotopes from the western part of Tapti graben, Deccan Syneclise, India. The geochemical results reveal sites or clusters of sites containing anomalously high concentrations of light hydrocarbon gases. High concentrations of adsorbed thermogenic methane (C1 = 518 ppb and ethane plus higher hydrocarbons (ΣC2+ = 977 ppb were observed. Statistical analysis shows that samples from 13% of the samples contain anomalously high concentrations of light hydrocarbons in the soil-gas constituents. This seepage suggests largest magnitude of soil gas anomalies might be generated/source from Mesozoic sedimentary rocks, beneath Deccan Traps. The carbon isotopic composition of methane, ethane and propane ranges are from −22.5‰ to −30.2‰ PDB, −18.0‰ to 27.1‰ PDB and 16.9‰–32.1‰ PDB respectively, which are in thermogenic source. Surface soil sample represents the intersection of a migration conduit from the deep subsurface to the surface connected to sub-trappean Mesozoic sedimentary rocks. Prominent hydrocarbon concentrations were associated with dykes, lineaments and presented on thinner basaltic cover in the study area

  6. The Dynamics of Oceanic Transform Faults: Constraints from Geophysical, Geochemical and Geodynamical Modeling

    Science.gov (United States)

    2008-06-01

    77 3.1 Benchmark: Comparison to EPR 9°N...supply may play an even greater role in controlling the ridge morphology than spreading rate. This paradox remains one of the first-order problems in...NAZCA 10’s- 110*W Figure 1. Regional map of the equatorial EPR showing large transform and non- transform offsets. Segmentation geometry is included

  7. Assessment of the hydrologic setting and mass transport within Saharan and Arabian Aquifers using GRACE, geochemical, geophysical and subsurface data

    Science.gov (United States)

    Sultan, M.; Sturchio, N. C.; Ahmed, M.; Saleh, S.; Mohamed, A.; Abuabdullah, M. M.; Emil, M. K.; Bettadpur, S. V.; Save, H.; Fathy, K.; Chouinard, K.

    2016-12-01

    A better understanding of the hydrologic setting, mass transport, origin, evolution, utilization, sustainability, and paleo-climatic recharge conditions of Saharan and Arabian aquifers was achieved by integrating observation from monthly (04/2002 to 03/2016) Gravity Recovery and Climate Experiment (GRACE)-derived Terrestrial Water Storage (TWS) from multiple GRACE solutions (mascons and spherical harmonic fields) with others from geochemical (solute chemistry), isotopic (O, H, Sr), geochronologic (Chlorine-36, Krypton-81), geophysical (aerogravity and aeromagnetic), and subsurface data. The investigated aquifers are: (1) Nubian Sandstone Aquifer System (NSAS; area: 2×106 km2) in northeast Africa and, (2) Mega Aquifer System (MAS; area: 1.1×106 km2) in Arabia. Our findings indicate the NSAS and MAS were largely recharged in previous wet climatic Pleistocene periods, as evidenced by the groundwater ages (up to 1 million years), yet they receive modest local recharge during interleaving dry periods in areas of relatively high (≥ 20 mm/yr) precipitation. In Sudan and Chad (southern NSAS), the average annual precipitation (AAP) is 95 mm/yr and the recharge is estimated at 3.2 x 109 m3/yr ( 7% of AAP); in the southwest parts of the MAS, the recharge at the foothills of the Red Sea mountains is 1.8 x 109 m3/yr (10% of AAP). Uplifts and/or shear zones orthogonal to groundwater flow impede the south to north flow in the NSAS as evidenced by the large differences in GRACE-derived TWS trends, groundwater ages, and isotopic compositions on either side of the east-west trending Uweinat-Aswan uplift. Similarly west to east groundwater flow in the MAS is impeded and impounded up-gradient from the N-S and/or NW-SE trending basement structures, reactivated during Red Sea opening. Shear zones subparallel to groundwater flow act as preferred flow pathways, as is the case with the NE-SW trending Pelusium shear zone which channels groundwater from the Kufra sub-basin (Libya

  8. Drill site selection process using geophysical (seismic, EM, magnetic) and regional geochemical uranium deposit vectors in the Athabasca Basin

    International Nuclear Information System (INIS)

    Hajnal, Z.; Takacs, E.; Pandit, B.

    2014-01-01

    Conclusions: • High resolution reflection technique, in correlation with other indicative vectors, provides primary structural and alteration information, within the Keefe L. prospect. • Several primary integrated attributes are indicative of mineralization within the SW. • The anomalous zones are more accurately defined in depths than any other geophysical technique, reduce drilling cost significantly.

  9. The examination of the spread of the leachates coming out of a solid waste disposal area on the ground with geophysical and geochemical methods (Sivas, Turkey)

    Science.gov (United States)

    Özel, Sevda; Yılmaz, Ali; Emin Candansayar, M.

    2017-03-01

    This study has been conducted in the irregular solid waste disposal area in the city of Sivas. The pollution spread formed by the leachates coming out of the disposal area has been examined with geophysical and geochemical works in this study. For this reason, the spread of the leachate pollution expanding in different geological units at both sides of a creek on the ground has been examined. For this purpose, the pollution spread has been examined with the methods of Direct Current Resistivity (DCR) and Electromagnetic Conductivity (EMC) and soil analyses. In the DCR method, 2D inversion of each sounding-profile datum measured alongside the lines parallel to each other and 3D inversion of the data measured in all the lines have been used in the interpretations. Apparent conductivity map has been attained from EMC measurements. The results of heavy metal analyses in the soil samples taken alongside the Haçin Creek have been assessed with the Spider diagram method. It has been determined that the flow of the leachate from geophysical models is in a SE direction and towards Kızılırmak and it continues vertically deeper than 4 m. In addition, it has been understood that the flow direction of the leachate is inspected by the geological structures. It has been understood from the geochemical results that the pollution in the soil stems from the leachate. In this way, it has been observed that the underground and surface water resources in the territory are under the threat of the pollution occurring due to the leachate.

  10. Surface geochemical data evaluation and integration with geophysical observations for hydrocarbon prospecting, Tapti graben, Deccan Syneclise, India

    OpenAIRE

    Satish Kumar, T.; Dayal, A.M.; Sudarshan, V.

    2014-01-01

    The Deccan Syneclise is considered to have significant hydrocarbon potential. However, significant hydrocarbon discoveries, particularly for Mesozoic sequences, have not been established through conventional exploration due to the thick basalt cover over Mesozoic sedimentary rocks. In this study, near-surface geochemical data are used to understand the petroleum system and also investigate type of source for hydrocarbons generation of the study area. Soil samples were collected from favorable...

  11. Geochemical and Geophysical Study in a Degraded Area Used for Disposal of Sludge from a Water Treatment Plant

    International Nuclear Information System (INIS)

    Moreira, R.C.A.; Nunes, S.A.; Da Silva, D.R.; Lira, C.P.; Boaventura, G.R.; Do Nascimento, C.T.C.; Moreira, R.C.A.; Pinheiro, L.A.

    2011-01-01

    The effects of disposal of sludge from water treatment plant (WTS) in area damaged by laterite extraction and its consequences to soil and groundwater were investigated. Therefore, the presence and concentration of anthropogenic elements and chemical compounds were determinated. WTS disposal's influence was characterized by electroresistivity method. The WTS's geochemical dispersion was noticed in the first meters of the non saturated zone from the lending area. Lateritic profiles were characterized due to the large variation in chemical composition between the horizons. Infiltration and percolation of rainwater through the WTS have caused migration of total dissolved solids to the groundwater. WTS's disposing area has more similarities to local preserved vegetation than to gravel bed area. WTS can be considered a noninert residue if disposed in degraded areas located in regions with similar geological and hydrochemical characteristics.

  12. The Conterminous United States Mineral Appraisal Program; background information to accompany folio of geologic, geochemical, geophysical, and mineral resources maps of the Tonopah 1 by 2 degree Quadrangle, Nevada

    Science.gov (United States)

    John, David A.; Nash, J.T.; Plouff, Donald; Whitebread, D.H.

    1991-01-01

    The Tonopah 1 ? by 2 ? quadrangle in south-central Nevada was studied by an interdisciplinary research team to appraise its mineral resources. The appraisal is based on geological, geochemical, and geophysical field and laboratory investigations, the results of which are published as a folio of maps, figures, and tables, with accompanying discussions. This circular provides background information on the investigations and integrates the information presented in the folio. The selected bibliography lists references to the geology, geochemistry, geophysics, and mineral deposits of the Tonopah 1 ? by 2 ? quadrangle.

  13. Late Cenozoic Magmatic and Tectonic Evolution of the Ancestral Cascade Arc in the Bodie Hills, California and Nevada: Insights from Integrated Geologic, Geophysical, Geochemical and Geochronologic Studies

    Science.gov (United States)

    John, D. A.; du Bray, E. A.; Box, S. E.; Blakely, R. J.; Fleck, R. J.; Vikre, P. G.; Cousens, B.; Moring, B. C.

    2012-12-01

    Geologic mapping integrated with new geophysical, geochemical, and geochronologic data characterize the evolution of Bodie Hills volcanic field (BHVF), a long-lived eruptive center in the southern part of the ancestral Cascade arc. The ~700 km2 field was a locus of magmatic activity from ~15 to 8 Ma. It includes >25 basaltic andesite to trachyandesite stratovolcanoes and silicic trachyandesite to rhyolite dome complexes. The southeastern part of the BHVF is overlain by the ~3.9 to 0.1 Ma, post-arc Aurora Volcanic Field. Long-lived BHVF magmatism was localized by crustal-scale tectonic features, including the Precambrian continental margin, the Walker Lane, the Basin and Range Province, and the Mina deflection. BHVF eruptive activity occurred primarily during 3 stages: 1) dominantly trachyandesite stratovolcanoes (~15.0 to 12.9 Ma), 2) coalesced trachydacite and rhyolite lava domes and trachyandesite stratovolcanoes (~11.6 to 9.7 Ma), and 3) dominantly silicic trachyandesite to dacite lava dome complexes (~9.2 to 8.0 Ma). Small rhyolite domes were emplaced at ~6 Ma. Relatively mafic stratovolcanoes surrounded by debris flow aprons lie on the margins of the BHVF, whereas more silicic dome fields occupy its center. Detailed gravity and aeromagnetic data suggest the presence of unexposed cogenetic granitic plutons beneath the center of the BHVF. Isotopic compositions of BHVF rocks are generally more radiogenic with decreasing age (e.g., initial Sr isotope values increase from ~0.7049 to 0.7061), which suggests progressively greater magma contamination by crustal components during evolution of the BHVF. Approximately circular, polygenetic volcanoes and scarcity of dikes suggest a low differential horizontal stress field during BHVF formation. Extensive alluvial gravel deposits that grade laterally into fluvial gravels and finer grained lacustrine sediments and the westerly sourced Eureka Valley Tuff (EVT; ~9.4 Ma) blanket large parts of the BHVF. The earliest sediments

  14. Use of geophysical and geochemical data in the analysis of the mud volcanoes in the absheron block

    International Nuclear Information System (INIS)

    Kulieva, R.; Connor, J.A

    2002-01-01

    Full text: The Absheron exploration block in the South Caspian Sea contains a single elongate anticline, which has structural closure from near the base of the Quaternary to the Middle Miocene, from about 1000 to 10,000 metres below se-level.A large mud volcano is visible on geophysical data close to the crest of the anticline, in the eastern part of the block.It is about 5 kms. In diameter at the sea floor, is almost flat-topped and stands approximately 60 metres above the surrounding seabed.Compressional wave seismic energy is almost completely reflected by the water-mud volcano interface, or absorbed within the upper few tens of metres of the mud volcano, which appears to be active. The surrounding quaternary sediments have had mud-volcanic material intruded into and extruded over them.The conduit for these gas-charged flows is assumed to be a fault,extending to the Oligocene-Early Miocene Mykop source rocks at a depth of 10 kms or more, though the fault is not imaged on seismic due to the lack of energy penetration under the volcano.The extent and nature of the intruded material have been analysed on seismic data.The surface of the mud volcano and its recent flows has been imaged on very high-resolution single channel seismic data and on side-scan sonar.Anomalies seen on gravity data recorded over the volcano have been used to estimate the lateral and vertical extent of the intruded sediments and their densities.Drop-coring surveys have sampled the sediments at the seabed at locations on and adjacent to the mud volcano.These samples have been analysed for geotechnical and geophysical properties, and for the chemical properties of gases extracted from them.The integration of all of these analyses has enabled a preliminary interpretation of the history of the mud volcanic activity, the nature of the breccias brought to the seafloor and the likely origin of the gas source of this activity.

  15. Final Report: Improved Site Characterization And Storage Prediction Through Stochastic Inversion Of Time-Lapse Geophysical And Geochemical Data

    Energy Technology Data Exchange (ETDEWEB)

    Ramirez, A; Mcnab, W; Hao, Y; White, D; Johnson, J

    2011-04-14

    During the last months of this project, our project activities have concentrated on four areas: (1) performing a stochastic inversion of pattern 16 seismic data to deduce reservoir bulk/shear moduli and density; the need for this inversion was not anticipated in the original scope of work, (2) performing a stochastic inversion of pattern 16 seismic data to deduce reservoir porosity and permeability, (3) complete the software needed to perform geochemical inversions and (4) use the software to perform stochastic inversion of aqueous chemistry data to deduce mineral volume fractions. This report builds on work described in progress reports previously submitted (Ramirez et al., 2009, 2010, 2011 - reports fulfilled the requirements of deliverables D1-D4) and fulfills deliverable D5: Field-based single-pattern simulations work product. The main challenge with our stochastic inversion approach is its large computational expense, even for single reservoir patterns. We dedicated a significant level of effort to improve computational efficiency but inversions involving multiple patterns were still intractable by project's end. As a result, we were unable to fulfill Deliverable D6: Field-based multi-pattern simulations work product.

  16. Blind Geothermal System Exploration in Active Volcanic Environments; Multi-phase Geophysical and Geochemical Surveys in Overt and Subtle Volcanic Systems, Hawai’i and Maui

    Energy Technology Data Exchange (ETDEWEB)

    Fercho, Steven [Ormat Nevada, Inc., Reno, NV (United States); Owens, Lara [Ormat Nevada, Inc., Reno, NV (United States); Walsh, Patrick [Ormat Nevada, Inc., Reno, NV (United States); Drakos, Peter [Ormat Nevada, Inc., Reno, NV (United States); Martini, Brigette [Corescan Inc., Ascot (Australia); Lewicki, Jennifer L. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Kennedy, Burton M. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2015-08-01

    Suites of new geophysical and geochemical exploration surveys were conducted to provide evidence for geothermal resource at the Haleakala Southwest Rift Zone (HSWRZ) on Maui Island, Hawai’i. Ground-based gravity (~400 stations) coupled with heli-bourne magnetics (~1500 line kilometers) define both deep and shallow fractures/faults, while also delineating potentially widespread subsurface hydrothermal alteration on the lower flanks (below approximately 1800 feet a.s.l.). Multi-level, upward continuation calculations and 2-D gravity and magnetic modeling provide information on source depths, but lack of lithologic information leaves ambiguity in the estimates. Additionally, several well-defined gravity lows (possibly vent zones) lie coincident with magnetic highs suggesting the presence of dike intrusions at depth which may represent a potentially young source of heat. Soil CO2 fluxes were measured along transects across geophysically-defined faults and fractures as well as young cinder cones along the HSWRZ. This survey generally did not detect CO2 levels above background, with the exception of a weak anomalous flux signal over one young cinder cone. The general lack of observed CO2 flux signals on the HSWRZ is likely due to a combination of lower magmatic CO2 fluxes and relatively high biogenic surface CO2 fluxes which mix with the magmatic signal. Similar surveys at the Puna geothermal field on the Kilauea Lower East Rift Zone (KLERZ) also showed a lack of surface CO2 flux signals, however aqueous geochemistry indicated contribution of magmatic CO2 and He to shallow groundwater here. As magma has been intercepted in geothermal drilling at the Puna field, the lack of measured surface CO2 flux indicative of upflow of magmatic fluids here is likely due to effective “scrubbing” by high groundwater and a mature hydrothermal system. Dissolved inorganic carbon (DIC) concentrations, δ13C compositions and 3He/4He values were sampled at Maui from several shallow

  17. Expanding Geophysical and Geochemical Investigation of Causes of Extraordinary Unrest at the Laguna del Maule (Rhyolitic) Volcanic Field, Southern Andes, Chile

    Science.gov (United States)

    Singer, B. S.

    2014-12-01

    The Laguna del Maule Volcanic Field, Chile, includes an unusually large and recent concentration of silicic eruptions. Since 2007 the crust here has been inflating at an astonishing rate of 25 cm/yr. Findings thus far lead to the hypothesis that the silicic vents have tapped an extensive layer of crystal-poor, rhyolitic melt that began to form atop a magmatic mush zone that was established by ~20 ka with a renewed phase of rhyolite eruptions during the Holocene. Modeling of surface deformation, magnetotelluric data, and gravity changes suggest that magma is currently intruding at a depth of ~5 km. Swarms of volcano-tectonic and long period earthquakes, mostly of M San Juan-Argentina, Nanyang Technological University-Singapore, SERNAGEOMIN, OVDAS, USGS, and SEGEMAR-Argentina. Team members will be introduced in this presentation. Our approach includes augmenting the OVDAS array of 6 permanent seisic stations with 40 additional instruments to conduct tomographic, receiver function and ambient noise studies. We continue to collect 4-D gravity data from 37 stations. Surface deformation is monitored via cGPS at 5 permanent receivers and InSAR data. A magnetotelluric survey across the Andes at 36o S is planned. Geochemical studies include mineral zoning and U-Th disequilibrium of zircons to constrain the timing of magma intrusion and mixing events prior to the current unrest. The overall aim is to integrate these observations and to construct numerical models of system dynamics. We are developing communications protocols and a web site to facilitate sharing of findings among the team members and with the public.

  18. Drill site selection process using geophysical (seismic, EM, magnetic) surveys and regional geochemical uranium deposit vectors within the Keefe Lake Uranium Property and its vicinity – Athabasca Basin, Saskatchewan, Canada

    International Nuclear Information System (INIS)

    Hajnal, Z.; Pandit, B.; Annesley, I.; Takacs, E.

    2014-01-01

    This study was initiated at the request of Athabasca Uranium Inc. of Vancouver, Canada. The area of investigation is around 4000 km"2 and includes the Keefe Lake (KL) property of the Company, located at the southeastern flank of the Athabasca Basin in Northern Saskatchewan. The intention of the program was multi-fold: to establish trends of regional uranium mineralization vectors, and incorporate these findings into the multidimensional integrated analysis of the currently available KL data set with an aim of providing an advanced priority ranking of drill hole selection process for the upcoming drilling programs. The information adapted for this investigation includes data from 450 boreholes, as well as drilling results of a recent KL prospect; data obtained from 114 Assessment Reports of the Saskatchewan Mineral Assessment Data Base (SMAD), and the analyses of 4 highresolution 2D seismic profiles within the claims of Athabasca Uranium Inc. To establish more effective spatial perspectives, the results of the regional lithology study (investigating alteration, graphitic, structural, pelitic, and pegmatitic features) were displayed along with the EM conductors, whereas basement lithology and faults were obtained from the Geological Atlas of Saskatchewan (southeastern segment of the Athabasca Basin). The regional investigation also included a study of the depth variations of the unconformity (UC), spatial vectors in geochemistry of the indicative path finder elements (U, Co, Cu, Ni, Pb, Zn, As, and B), and also the clay mineralization (illite and kaolinite) indicative of uranium mineralization related to alteration zones. Local area investigations consisted of integrating the AEROTEM (2009) and VTEM (2013) airborne EM data, the associated magnetic observations, and computation of relevant attributes. The comprehensive synthesis of the above geophysical information incorporated all the available and derived geological perspectives. The high-resolution 2D seismic data

  19. Application of the geophysical and geochemical methods to the research for uranium; Application a la recherche de l'uranium des methodes geophysiques et geochimiques

    Energy Technology Data Exchange (ETDEWEB)

    Gangloff, A M; Collin, C R; Grimbert, A; Sanselme, H [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1958-07-01

    Since 1954, at the Commissariat a l'energie atomique, geophysics and geochemistry have been added to routine geological surveying and radiometric observations. Geophysical prospecting reveals the tectonic structures linked with French uranium deposits and gives an idea of favorable zones. Geochemistry adds to the geophysical indirect methods further details on the distribution of uranium traces in the soils. This method is direct and specific. Uranium assay in waters and alluvial deposits find its use in preliminary exploration. (author) [French] Depuis 1954, au CEA, a l'observation geologique directe et aux mesures radiometriques, sont venues s'ajouter des methodes relevant de la geophysique et de la geochimie. La prospection geophysique apporte des precisions sur les structures tectoniques auxquelles sont lies les gisements d'uranium fran is et sur la notion de zones favorables. Aux methodes indirectes de la geophysique, la prospection geochimique ajoute des precisions sur la repartition de l'uranium en traces dans les sols, cette methode est directe et specifique. Le dosage de l'uranium dans les eaux et les alluvions trouve son application dans la prospection de reconnaissance. (auteur)

  20. The application actualities and prospects of geophysical methods to uranium prospecting

    International Nuclear Information System (INIS)

    Liu Qingcheng

    2010-01-01

    Basic principles of geophysical methods to uranium prospect are briefly introduced, and the effects as well as problems in using those methods are analysed respectively. Combining with the increasing demand of uranium resources for Chinese nuclear power development and the higher requirements of geophysical techniques, the developing directions and the thoughts of geophysical techniques in uranium prospecting were proposed. A new pattern with producing, teaching and researching together is brought forward to develop advancing uranium prospecting key technologies and to break through technological bottlenecks depending on independent innovation. Integrated geophysical methods for prospecting uranium deposits are suggested. The method includes geophysical techniques as follows: gravity, magnetic, seismic, radioactive, remote sensing, and geochemical method in some proving grounds. Based on the experimental research, new uranium deposits prospecting models with efficient integrated geophysical methods can be established. (authors)

  1. Geophysical Signitures From Hydrocarbon Contaminated Aquifers

    Science.gov (United States)

    Abbas, M.; Jardani, A.

    2015-12-01

    The task of delineating the contamination plumes as well as studying their impact on the soil and groundwater biogeochemical properties is needed to support the remediation efforts and plans. Geophysical methods including electrical resistivity tomography (ERT), induced polarization (IP), ground penetrating radar (GPR), and self-potential (SP) have been previously used to characterize contaminant plumes and investigate their impact on soil and groundwater properties (Atekwana et al., 2002, 2004; Benson et al., 1997; Campbell et al., 1996; Cassidy et al., 2001; Revil et al., 2003; Werkema et al., 2000). Our objective was to: estimate the hydrocarbon contamination extent in a contaminated site in northern France, and to adverse the effects of the oil spill on the groundwater properties. We aim to find a good combination of non-intrusive and low cost methods which we can use to follow the bio-remediation process, which is planned to proceed next year. We used four geophysical methods including electrical resistivity tomography, IP, GPR, and SP. The geophysical data was compared to geochemical ones obtained from 30 boreholes installed in the site during the geophysical surveys. Our results have shown: low electrical resistivity values; high chargeability values; negative SP anomalies; and attenuated GPR reflections coincident with groundwater contamination. Laboratory and field geochemical measurements have demonstrated increased groundwater electrical conductivity and increased microbial activity associated with hydrocarbon contamination of groundwater. Our study results support the conductive model suggested by studies such as Sauck (2000) and Atekwana et al., (2004), who suggest that biological alterations of hydrocarbon contamination can substantially modify the chemical and physical properties of the subsurface, producing a dramatic shift in the geo-electrical signature from resistive to conductive. The next stage of the research will include time lapse borehole

  2. Environmental geophysics and geochemistry for contamination mapping and monitoring 1

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Tai Sup; Lee, Sang Kyu; Hong, Young Kook [Korea Inst. of Geology Mining and Materials, Taejon (Korea, Republic of); and others

    1995-12-01

    This study aims to provide the technologies which can be practically used for contamination mapping and monitoring. To accomplish this goal, the geophysical and geochemical expertise and techniques commonly used in the mineral resources exploration are employed. In the first year of the three-year-long project, the purpose of the study is to introduce the optimum methodologies among the geophysical and geochemical techniques to tackle the various cases of environmental contamination. To achieve the purpose, case studies of the developed countries were surveyed and analyzed through the various kinds of literatures. The followings are categorized to be solved by geophysical methods: 1) delineation of water system pollution by acid mine drainage and distributions of waste rocks in the closed mine area, 2) defining boundaries of subsurface contamination due to oil seepage, 3) zoning of sea water intrusion in the seashore or subsurface geology highly containing salt, 4) locating of buried metallic wastes such as pipes and drums which can cause the secondary pollution by corrosion, and 5) outlining of the subsurface area polluted by leachate from the landfill. To experiment the above items, various geophysical methods were applied to the corresponding test sites. From these experiments, the applicabilities of the respective geophysical method were analyzed, and the optimum methods were derived for the various pollution types. Furthermore, electric and electromagnetic surveys data processing software were developed to quantitatively interpret and highly resolve the geology. The environmental assignments which can be solved by geochemical methods include: 1) drainage pollution by coal mine effluents, 2)subsurface contamination of oil-spill, 3) sea water intrusion, 4) dispersion of toxic heavy metallic elements in the metal mines, and 5) radon environmental geochemistry. The appropriate test sites for applying the geochemical methods were selected. (Abstract Truncated)

  3. Geophysical, geochemical and hydrological analyses of water-resource vulnerability to salinization: case of the Uburu-Okposi salt lakes and environs, southeast Nigeria

    Science.gov (United States)

    Ukpai, S. N.; Okogbue, C. O.

    2017-11-01

    Until this study, the location and depth of the saline units in Uburu-Okposi salt lake areas and environs have been unknown. This study aimed at delineating the saline lithofacies and dispersal configurations to water bodies, using electrical geophysical methods such as constant separation traversing (CST) and vertical electrical sounding (VES). Results showed weathered zones that represent aquifers mostly at the fourth geoelectric layer: between upper layered aquitards and underlying aquitards at depths 30-140 m. Lateral distribution of resistivity variance was defined by the CST, whereas the VES tool, targeted at low-resistivity zones, detected isolated saline units with less than 10 ohm-m at depths generally >78 m. The saline lithofacies were suspected to link freshwater zones via shear zones, which steer saline water towards the salt lakes and influence the vulnerability of groundwater to salinization. The level of salinization was verified by water sampling and analysis, and results showed general alkaline water type with a mean pH of 7.66. Water pollution was indicated: mean total dissolved solids (TDS) 550 mg/l, electrical conductivity (EC) 510 μS/cm, salinity 1.1‰, Cl- 200 mg/l, N03 -35.5 mg/l, Na+ 19.6 mg/l and Ca2+ 79.3 mg/l. The salinity is controlled by NaCl salt, as deduced from correlation analysis using the software package Statistical Product for Service Solutions (SPSS). Generally, concentrations of dissolved ions in the water of the area are enhanced via mechanisms such as evaporation, dissociation of salts, precipitation run off and leaching of dissolved rock minerals.

  4. Combining geochemical tracers with geophysical tools to study groundwater quality in Mesilla Bolson of the semi-arid Rio Grande watershed

    Science.gov (United States)

    Ma, L.; Hiebing, M.; Garcia, S.; Szynkiewicz, A.; Doser, D. I.

    2017-12-01

    Mesilla Bolson is an important alluvial aquifer system of the semi-arid Rio Grande watershed in southern New Mexico and West Texas. It is one of the two major groundwater sources for the City of El Paso in Texas and provides about 30% of the region's domestic groundwater needs. Groundwater from Mesilla Bolson is also extensively used for agriculture irrigation in this region. However, high concentrations of total dissolved solids in some areas of this region significantly impact groundwater quality for the Rio Grande alluvial aquifer. For example, an increase in groundwater salinity is generally observed from north to south within the aquifer. Some previous researchers have suggested this salinity change is due to 1) runoff and recharge from agricultural activity; 2) natural upwelling of deeper brackish groundwater; and 3) water-rock interactions in the aquifer. To better study how agricultural and municipal practices contribute to increasing salinity, we sampled 50 wells of the Mesilla Bolson in 2015-2016 for uranium (234U/238U), strontium (87Sr/86Sr), boron (d11B), and sulfur (d34S) isotope compositions to characterize major salinity sources of groundwater. In addition, we applied a geophysical gravity survey to determine the possible influences of faults and other subsurface structures on groundwater quality in this region. Our multi-isotope results suggest that the groundwater resources of this alluvial aquifer have been already impacted by human activities and groundwater recharge to the alluvial aquifer is affected by surface processes such as i) the return flows from the Rio Grande surface water used for irrigation, ii) municipal discharges, and iii) irrigation with the reclaimed city water. However, natural upwelling is also probably responsible for the salinity increase near some fault areas, primarily due to water-rock interactions such as dissolution of evaporites within the deeper basin. In some areas of the Mesilla Bolson, fault systems act as conduits

  5. An integrated geochemical, geophysical and mineralogical study of river sediments in alpine area and soil samples near steel plant, in Austria

    Science.gov (United States)

    Irfan, M. I.; Meisel, T.

    2012-04-01

    Concentration of nickel and chromium in any part of the ecosystem is important for environmental concerns in particular human health due to the reason that some species of them can cause health problem e.g. dermatitis and cancer. Sediment samples collected form a river Vordernberger Bach (Leoben, Austria) in an alpine region and soil samples collected in an area adjacent to steel production unit in same narrow valley were investigated. In previous studies a correlation between magnetic susceptibility values and concentration of nickel and chromium showed that a magnetic susceptibility meter can be used to point out the contaminated areas as in-situ device. The purpose of the whole study is to understand the real (point or diffuse, anthropogenic or geogenic) sources of contamination of soils, water and river sediments through heavy metal deposition. Unseparated, magnetic and non-magnetic fractions of soil samples were investigated for geochemical and mineralogical aspects with XRF, ICP-MS, EMPA, Multi-Functional Kappabridge (MFK1) and laser ablation coupled with ICP-MS. Mineralogical study of sediment samples for several sampling points with higher Ni and Cr content was performed. Sediment samples were sieved below 1.4 mm and then a concentrate of heavy minerals was prepared in the field through panning. Concentrated heavy minerals were then subjected for heavy liquid separation in the laboratory. Separated magnetic and non-magnetic fractions below 0.71/0.1 mm and density greater than 2.9 g/cm3 were selected for mineralogical investigation. The abundance of typical anthropogenic particles, e.g., spherical, tinder, roasted ores, iron and steel mill slag was observed under the microscope. Magnetite (mostly anthropogenic), maghemite, chromspinel, chromite (type I & II), (Ca,Al)-ferrite, wustite, apatite (anthropogenic), olivine mixed crystals, calcium silicate and spinel (anthropogenic) are found in magnetic fraction. Non-magnetic fractions contain hematite, siderite

  6. Geophysical Field Theory

    International Nuclear Information System (INIS)

    Eloranta, E.

    2003-11-01

    The geophysical field theory includes the basic principles of electromagnetism, continuum mechanics, and potential theory upon which the computational modelling of geophysical phenomena is based on. Vector analysis is the main mathematical tool in the field analyses. Electrostatics, stationary electric current, magnetostatics, and electrodynamics form a central part of electromagnetism in geophysical field theory. Potential theory concerns especially gravity, but also electrostatics and magnetostatics. Solid state mechanics and fluid mechanics are central parts in continuum mechanics. Also the theories of elastic waves and rock mechanics belong to geophysical solid state mechanics. The theories of geohydrology and mass transport form one central field theory in geophysical fluid mechanics. Also heat transfer is included in continuum mechanics. (orig.)

  7. 77 FR 19321 - Geological and Geophysical Exploration on the Atlantic Outer Continental Shelf (OCS)

    Science.gov (United States)

    2012-03-30

    ... DEPARTMENT OF THE INTERIOR Bureau of Ocean Energy Management Geological and Geophysical... Statement (PEIS) to evaluate potential environmental effects of multiple Geological and Geophysical (G&G... limited to, seismic surveys, sidescan-sonar surveys, electromagnetic surveys, geological and geochemical...

  8. Geophysical considerations of geothermics

    Energy Technology Data Exchange (ETDEWEB)

    Hayakawa, M

    1967-01-01

    The development and utilization of geothermal energy is described from the standpoint of geophysics. The internal temperature of the Earth and the history and composition of magmas are described. Methods of exploration such as gravity, magnetic, thermal and electrical surveys are discussed, as are geochemical and infrared photogrammetric techniques. Examples are provided of how these techniques have been used in Italy and at the Matsukawa geothermal field in Japan. Drilling considerations such as muds, casings and cementing materials are discussed. Solutions are proposed for problems of environmental pollution and plant expansion.

  9. Geophysical investigations in the Kivetty area, Finland

    International Nuclear Information System (INIS)

    Heikkinen, E.; Paananen, M.; Oehberg, A.; Front, K.; Okko, O.; Pitkaenen, P.

    1992-09-01

    Investigations were carried out at Kivetty site in Konginkangas, in central Finland, by geological, geophysical, geohydrological and geochemical methods in 1987-1991 to determine the suitability of the bedrock for the final disposal of spent nuclear fuel. Airborne, ground and borehole geophysical methods were used to study the rock type distribution, fracturing and hydraulic conductivity of the bedrock to a depth of one kilometre

  10. Geophysical investigations in the Syyry area, Finland

    International Nuclear Information System (INIS)

    Heikkinen, E.; Kurimo, M.

    1992-12-01

    Investigations were carried out at the Syyry site at Sievi using geological, geophysical, geohydrological and geochemical methods in 1987-1991 to determine the suitability of the bedrock for the final disposal of spent nuclear fuel. In this survey airborne, ground and borehole geophysical methods were used to study the rock type distribution, fracturing and hydraulic conductivity of the bedrock to a depth of one kilometre

  11. Geophysical investigations in the Olkiluoto area, Finland

    International Nuclear Information System (INIS)

    Heikkinen, E.; Paananen, M.

    1992-12-01

    Investigations were carried out at the Olkiluoto site at Eurajoki using geological, geophysical, geohydrological and geochemical methods in 1987-1992 to determine the suitability of the bedrock for the final disposal of spent nuclear fuel. In this survey airborne, ground and borehole geophysical methods were used to study the rock type distribution, fracturing and hydraulic conductivity of the bedrock to a depth of one kilometre

  12. Geophysics- and geochemistry-based assessment of the geochemical characteristics and groundwater-flow system of the U.S. part of the Mesilla Basin/Conejos-Médanos aquifer system in Doña Ana County, New Mexico, and El Paso County, Texas, 2010–12

    Science.gov (United States)

    Teeple, Andrew P.

    2017-06-16

    One of the largest rechargeable groundwater systems by total available volume in the Rio Grande/Río Bravo Basin (hereinafter referred to as the “Rio Grande”) region of the United States and Mexico, the Mesilla Basin/Conejos-Médanos aquifer system, supplies water for irrigation as well as for cities of El Paso, Texas; Las Cruces, New Mexico; and Ciudad Juárez, Chihuahua, Mexico. The U.S. Geological Survey in cooperation with the Bureau of Reclamation assessed the groundwater resources in the Mesilla Basin and surrounding areas in Doña Ana County, N. Mex., and El Paso County, Tex., by using a combination of geophysical and geochemical methods. The study area consists of approximately 1,400 square miles in Doña Ana County, N. Mex., and 100 square miles in El Paso County, Tex. The Mesilla Basin composes most of the study area and can be divided into three parts: the Mesilla Valley, the West Mesa, and the East Bench. The Mesilla Valley is the part of the Mesilla Basin that was incised by the Rio Grande between Selden Canyon to the north and by a narrow valley (about 4 miles wide) to the southeast near El Paso, Tex., named the Paso del Norte, which is sometimes referred to in the literature as the “El Paso Narrows.”Previously published geophysical data for the study area were compiled and these data were augmented by collecting additional geophysical and geochemical data. Geophysical resistivity measurements from previously published helicopter frequency domain electromagnetic data, previously published direct-current resistivity soundings, and newly collected (2012) time-domain electromagnetic soundings were used in the study to detect spatial changes in the electrical properties of the subsurface, which reflect changes that occur within the hydrogeology. The geochemistry of the groundwater system was evaluated by analyzing groundwater samples collected in November 2010 for physicochemical properties, major ions, trace elements, nutrients, pesticides

  13. Novel geochemical techniques integrated in exploration for uranium deposits at depth

    International Nuclear Information System (INIS)

    Kyser, K.

    2014-01-01

    Mineral deposits are in fact geochemical anomalies, and as such their detection and assessment of their impact on the environment should be facilitated using geochemical techniques. Although geochemistry has been used directly in the discovery of uranium deposits and more indirectly in shaping deposit models, the novel applications of geochemistry and integration with other data can be more effective in formulating exploration and remediation strategies. Recent research on the use of geochemistry in detecting uranium deposits at depth include: (1) more effective integration of geochemical with geophysical data to refine targets, (2) revealing element distributions in and around deposits to adequately assess the total chemical environment associated with the deposit, (3) the use of element tracing using elemental concentrations and isotopic compositions in the near surface environment to detect specific components that have migrated to the surface from uranium deposits at depth, (4) understand the effects of both macro- and micro-environments on element mobility across the geosphere-biosphere interface to enhance exploration using select media for uranium at depth. Geophysical data used in exploration can identify areas of conductors where redox contrasts may host mineralization, structures that act to focus fluids during formation of the deposits and act as conduits for element migration to the surface, and contrasts in geology that are required for the deposits. However, precision of these data is greatly diminished with depth, but geochemical data from drill core or surface media can enhance target identification when integrated with geophysical data. Geochemical orientation surveys over known unconformity-related deposits at depth clearly identify mineralization 900m deep. Drill core near the deposit, clay-size fractions separated from soil horizons and vegetation over and far from the deposit record element migration from the deposit as radiogenic He, Rn and Pb

  14. Geophysical characterization from Itu intrusive suite

    International Nuclear Information System (INIS)

    Pascholati, M.E.

    1989-01-01

    The integrated use of geophysical, geological, geochemical, petrographical and remote sensing data resulted in a substantial increase in the knowledge of the Itu Intrusive Suite. The main geophysical method was gamma-ray spectrometry together with fluorimetry and autoradiography. Three methods were used for calculation of laboratory gamma-ray spectrometry data. For U, the regression method was the best one. For K and Th, equations system and absolute calibration presented the best results. Surface gamma-ray spectrometry allowed comparison with laboratory data and permitted important contribution to the study of environmental radiation. (author)

  15. Petroleum geophysics

    Energy Technology Data Exchange (ETDEWEB)

    2010-07-01

    The book is compiled from a series of e-learning modules. GeoCLASS is an e-learning system with contents from petroleum geophysics. It is the result of collaboration between professors at the University of Bergen and the University of Oslo, and its material has been used as curriculum in master program courses at these universities for several years. Using a unique feature to GeoCLASS, these advanced scientific topics are presented on multiple levels. The introductions open the door to this vast pool of knowledge, accessible even for high school students. Enter the door, and you enter the modules. Various levels of content are presented, and the more advanced levels can be shielded from the regular user, and only accessed by those with particular interest. The chapters in the book are: Elastic waves; Survey planning; Seismic acquisition; Basic seismic signal theory and processing; Seismic imaging; Seismic attributes; Rock physics; Reservoir monitoring. (AG)

  16. Geophysical Monitoring of Hydrological and Biogeochemical Transformations associated with Cr(VI) Bioremediation

    International Nuclear Information System (INIS)

    Hubbard, Susan; Williams, Kenneth H.; Conrad, Mark E.; Faybishenko, Boris; Peterson, John; Chen, Jinsong; Long, Philip E.; Hazen, Terry C.

    2008-01-01

    Understanding how hydrological and biogeochemical properties change over space and time in response to remedial treatments is hindered by our ability to monitor these processes with sufficient resolution and over field relevant scales. Here, we explored the use of geophysical approaches for monitoring the spatiotemporal distribution of hydrological and biogeochemical transformations associated with a Cr(VI)bioremediation experiment performed at Hanford, WA. We first integrated hydrological wellbore and geophysical tomographic datasets to estimate hydrological zonation at the study site. Using results from laboratory biogeophysical experiments and constraints provided by field geochemical datasets, we then interpreted time-lapse seismic and radar tomographic datasets, collected during thirteen acquisition campaigns over a three year experimental period, in terms of hydrological and biogeochemical transformations. The geophysical monitoring datasets were used to infer: the spatial distribution of injected electron donor; the evolution of gas bubbles; variations in total dissolved solids (nitrate and sulfate) as a function of pumping activity; the formation of precipitates and dissolution of calcites; and concomitant changes in porosity. Although qualitative in nature, the integrated interpretation illustrates how geophysical techniques have the potential to provide a wealth of information about coupled hydrobiogeochemical responses to remedial treatments in high spatial resolution and in a minimally invasive manner. Particularly novel aspects of our study include the use of multiple lines of evidence to constrain the interpretation of a long-term, field-scale geophysical monitoring dataset and the interpretation of the transformations as a function of hydrological heterogeneity and pumping activity

  17. ANNALS OF GEOPHYSICS: AD MAJORA

    Directory of Open Access Journals (Sweden)

    Fabio Florindo

    2014-03-01

    Full Text Available Annals of Geophysics is a bimonthly international journal, which publishes scientific papers in the field of geophysics sensu lato. It derives from Annali di Geofisica, which commenced publication in January 1948 as a quarterly periodical devoted to general geophysics, seismology, earth magnetism, and atmospheric studies. The journal was published regularly for a quarter of a century until 1982 when it merged with the French journal Annales de Géophysique to become Annales Geophysicae under the aegis of the European Geophysical Society. In 1981, this journal ceased publication of the section on solid earth geophysics, ending the legacy of Annali di Geofisica. In 1993, the Istituto Nazionale di Geofisica (ING, founder of the journal, decided to resume publication of its own journal under the same name, Annali di Geofisica. To ensure continuity, the first volume of the new series was assigned the volume number XXXVI (following the last issue published in 1982. In 2002, with volume XLV, the name of the journal was translated into English to become Annals of Geophysics and in consequence the journal impact factor counter was restarted. Starting in 2010, in order to improve its status and better serve the science community, Annals of Geophysics has instituted a number of editorial changes including full electronic open access, freely accessible online, the possibility to comment on and discuss papers online, and a board of editors representing Asia and the Americas as well as Europe. [...

  18. Preliminary report on geophysics ground follow-up of the 1977 airborne survey in the Wadi Bidah District, Kingdom of Saudi Arabia

    Science.gov (United States)

    Flanigan, V.J.; Wynn, J.C.; Worl, R.G.; Smith, C.W.

    1981-01-01

    Reconnaissance geologic and geochemical sampling was made during the 1978 field season at most of the 50 or so electromagnetic anomalies detected in the 1977 airborne electromagnetic (AEM) survey of the Wadi Bidah district. These Phase 1 studies also included reconnaissance geophysical traverses of nine of the AEM conductors. In addition the AEM anomalies were classified on the basis of this reconnaissance work into a list of priority targets for use in economic studies, and six AEM anomalies were selected for further studies.

  19. The 'glass earth' - geochemical frontiers in exploration through cover

    International Nuclear Information System (INIS)

    Carr, G.; Denton, G.; Giblin, A.; Korsch, M.; Andrew, A.; Whitford, D.

    1999-01-01

    'Glass Earth' represents a number of current and planned projects within CSIRO aimed at making 'transparent' the top 1000 m of the Earth's crust It builds upon current technologies developed within a number of CSIRO divisions as well as the Australian Mineral Exploration Technologies CRC (AMET CRC), the Australian Geodynamics CRC (AG CRC) and the CRC for Landscape Evolution and Mineral Exploration (CRC LEME). New geophysical and geochemical technologies will be developed to complement these, together with new capabilities in modelling, data integration and visualisation, including hydrogeochemistry, hydrogeology, surface geochemistry and isotope geochemistry, modelling of chemical, fluid and heat flows in rock and regolith, advanced visualisation and data fusion. This paper describes some recent work in the field of isotope geochemistry, with the principal aim of 'seeing through' cover to understand basement geology and detect hidden ore systems

  20. Major results of geophysical investigations at Yucca Mountain and vicinity, southern Nevada

    International Nuclear Information System (INIS)

    Oliver, H.W.; Ponce, D.A.; Hunter, W.C.

    1995-01-01

    In the consideration of Yucca Mountain as a possible site for storing high level nuclear waste, a number of geologic concerns have been suggested for study by the National Academy of Sciences which include: (1) natural geologic and geochemical barriers, (2) possible future fluctuations in the water table that might flood a mined underground repository, (3) tectonic stability, and (4) considerations of shaking such as might be caused by nearby earthquakes or possible volcanic eruptions. This volume represents the third part of an overall plan of geophysical investigation of Yucca Mountain, preceded by the Site Characterization Plan (SCP; dated 1988) and the report referred to as the Geophysical White Paper, Phase 1, entitled Status of Data, Major Results, and Plans for Geophysical Activities, Yucca Mountain Project (Oliver and others, 1990). The SCP necessarily contained uncertainty about applicability and accuracy of methods then untried in the Yucca Mountain volcano-tectonic setting, and the White Paper, Phase 1, focused on summarization of survey coverage, data quality, and applicability of results. For the most part, it did not present data or interpretation. The important distinction of the current volume lies in presentation of data, results, and interpretations of selected geophysical methods used in characterization activities at Yucca Mountain. Chapters are included on the following: gravity investigations; magnetic investigations; regional magnetotelluric investigations; seismic refraction investigations; seismic reflection investigations; teleseismic investigations; regional thermal setting; stress measurements; and integration of methods and conclusions. 8 refs., 60 figs., 2 tabs

  1. The geochemical atlas of Alaska, 2016

    Science.gov (United States)

    Lee, Gregory K.; Yager, Douglas B.; Mauk, Jeffrey L.; Granitto, Matthew; Denning, Paul; Wang, Bronwen; Werdon, Melanie B.

    2016-06-21

    A rich legacy of geochemical data produced since the early 1960s covers the great expanse of Alaska; careful treatment of such data may provide significant and revealing geochemical maps that may be used for landscape geochemistry, mineral resource exploration, and geoenvironmental investigations over large areas. To maximize the spatial density and extent of data coverage for statewide mapping of element distributions, we compiled and integrated analyses of more than 175,000 sediment and soil samples from three major, separate sources: the U.S. Geological Survey, the National Uranium Resource Evaluation program, and the Alaska Division of Geological & Geophysical Surveys geochemical databases. Various types of heterogeneity and deficiencies in these data presented major challenges to our development of coherently integrated datasets for modeling and mapping of element distributions. Researchers from many different organizations and disparate scientific studies collected samples that were analyzed using highly variable methods throughout a time period of more than 50 years, during which many changes in analytical techniques were developed and applied. Despite these challenges, the U.S. Geological Survey has produced a new systematically integrated compilation of sediment and soil geochemical data with an average sample site density of approximately 1 locality per 10 square kilometers (km2) for the entire State of Alaska, although density varies considerably among different areas. From that compilation, we have modeled and mapped the distributions of 68 elements, thus creating an updated geochemical atlas for the State.

  2. Geochemical assessment of light gaseous hydrocarbons in near ...

    Indian Academy of Sciences (India)

    Light hydrocarbons in soil have been used as direct indicators in geochemical hydrocarbon exploration, which remains an unconventional path in the petroleum industry. The occurrence of adsorbed soil ... Kalpana1 D J Patil1 A M Dayal1. National Geophysical Research Institute, Uppal Road, Hyderabad 500606, India.

  3. Released geophysical and geological reports : Newfoundland offshore area September 2003

    International Nuclear Information System (INIS)

    2003-09-01

    This two-part publication contains a list of geophysical and geological data acquired by the Canada-Newfoundland Offshore Petroleum Board (C-NOPB). It is made available to the public in accordance with a subsection of the Canada-Newfoundland Atlantic Accord Implementation Act which states that such data can be released five years after the date of completion of a program. The programs for which the data has been released are listed in chronological order by completion date. A list of wells drilled within the C-NOPB's jurisdictional area is also included along with a map showing the area of jurisdiction. The well data includes category 1 information from exploratory wells, delineation wells, and development wells. It includes factual data obtained directly from well drilling which must be made available for public examination 2 years after well completion. Category 1 data refers to drill cuttings, well fluid samples, open-hole logs, formation stimulation data, petroleum analyses, drill mud reports, and well site survey information. The interpretive geological and geophysical reports are based on industry data from exploratory programs conducted in the Newfoundland offshore area. They include information from synthetic seismograms, velocity surveys, vertical seismic profiles, petrological reports, geochemical reports, and cyberlook logs. The jurisdictional areas include Western Newfoundland, South Grand Banks, North Grand Banks, the Northeast Newfoundland Shelf, and the Labrador Shelf. Program numbers are coded to contain the geographic region to which the program relates, the type of proposed geophysical or geological work, the company operating the program, and the sequential number of that type of program operated by each company. 8 tabs

  4. Sustainable urban development and geophysics

    Science.gov (United States)

    Liu, Lanbo; Chan, L. S.

    2007-09-01

    The new millennium has seen a fresh wave of world economic development especially in the Asian-Pacific region. This has contributed to further rapid urban expansion, creating shortages of energy and resources, degradation of the environment, and changes to climatic patterns. Large-scale, new urbanization is mostly seen in developing countries but urban sprawl is also a major social problem for developed nations. Urbanization has been accelerating at a tremendous rate. According to data collected by the United Nations [1], 50 years ago less than 30% of the world population lived in cities. Now, more than 50% are living in urban settings which occupy only about 1% of the Earth's surface. During the period from 1950 to 1995, the number of cities with a population higher than one million increased from 83 to 325. By 2025 it is estimated that more than 60% of 8.3 billion people (the projected world population [1]) will be city dwellers. Urbanization and urban sprawl can affect our living quality both positively and negatively. In recent years geophysics has found significant and new applications in highly urbanized settings. Such applications are conducive to the understanding of the changes and impacts on the physical environment and play a role in developing sustainable urban infrastructure systems. We would like to refer to this field of study as 'urban geophysics'. Urban geophysics is not simply the application of geophysical exploration in the cities. Urbanization has brought about major changes to the geophysical fields of cities, including those associated with electricity, magnetism, electromagnetism and heat. An example is the increased use of electromagnetic waves in wireless communication, transportation, office automation, and computer equipment. How such an increased intensity of electromagnetic radiation affects the behaviour of charged particles in the atmosphere, the equilibrium of ecological systems, or human health, are new research frontiers to be

  5. Geochemical computer codes. A review

    International Nuclear Information System (INIS)

    Andersson, K.

    1987-01-01

    In this report a review of available codes is performed and some code intercomparisons are also discussed. The number of codes treating natural waters (groundwater, lake water, sea water) is large. Most geochemical computer codes treat equilibrium conditions, although some codes with kinetic capability are available. A geochemical equilibrium model consists of a computer code, solving a set of equations by some numerical method and a data base, consisting of thermodynamic data required for the calculations. There are some codes which treat coupled geochemical and transport modeling. Some of these codes solve the equilibrium and transport equations simultaneously while other solve the equations separately from each other. The coupled codes require a large computer capacity and have thus as yet limited use. Three code intercomparisons have been found in literature. It may be concluded that there are many codes available for geochemical calculations but most of them require a user that us quite familiar with the code. The user also has to know the geochemical system in order to judge the reliability of the results. A high quality data base is necessary to obtain a reliable result. The best results may be expected for the major species of natural waters. For more complicated problems, including trace elements, precipitation/dissolution, adsorption, etc., the results seem to be less reliable. (With 44 refs.) (author)

  6. Regional geochemical maps of the Tonopah 1 degree by 2 degrees Quadrangle, Nevada, based on samples of stream sediment and nonmagnetic heavy-mineral concentrate

    Science.gov (United States)

    Nash, J.T.; Siems, D.F.

    1988-01-01

    This report is part of a series of geologic, geochemical, and geophysical maps of the Tonopah 1° x 2° quadrangle, Nevada, prepared during studies of the area for the Conterminous United States Mineral Assessment Program (CUSMAP). Included here are 21 maps showing the distributions of selected elements or combinations of elements. These regional geochemical maps are based on chemical analyses of the minus-60 mesh (0.25 mm) fraction of stream-sediment samples and the nonmagnetic heavy-mineral concentrate derived from stream sediment. Stream sediments were collected at 1,217 sites. Our geochemical studies of mineralized rock samples provide a framework for evaluating the results from stream sediments.

  7. Proceedings of the workshop on geochemical modeling

    International Nuclear Information System (INIS)

    1986-01-01

    The following collection of papers was presented at a workshop on geochemical modeling that was sponsored by the Office of Civilian Radioactive Waste Management Program at the Lawrence Livermore National Laboratory (LLNL). The LLNL Waste Management Program sponsored this conference based on their belief that geochemical modeling is particularly important to the radioactive waste disposal project because of the need to predict the consequences of long-term water-rock interactions at the proposed repository site. The papers included in this volume represent a subset of the papers presented at the Fallen Leaf Lake Conference and cover a broad spectrum of detail and breadth in a subject that reflects the diverse research interests of the conference participants. These papers provide an insightful look into the current status of geochemical modeling and illustrate how various geochemical modeling codes have been applied to problems of geochemical interest. The emphasis of these papers includes traditional geochemical modeling studies of individual geochemical systems, the mathematical and theoretical development and refinement of new modeling capabilities, and enhancements of data bases on which the computations are based. The papers in this proceedings volume have been organized into the following four areas: Geochemical Model Development, Hydrothermal and Geothermal Systems, Sedimentary and Low Temperature Environments, and Data Base Development. The participants of this symposium and a complete list of the talks presented are listed in the appendices

  8. Proceedings of the workshop on geochemical modeling

    Energy Technology Data Exchange (ETDEWEB)

    1986-01-01

    The following collection of papers was presented at a workshop on geochemical modeling that was sponsored by the Office of Civilian Radioactive Waste Management Program at the Lawrence Livermore National Laboratory (LLNL). The LLNL Waste Management Program sponsored this conference based on their belief that geochemical modeling is particularly important to the radioactive waste disposal project because of the need to predict the consequences of long-term water-rock interactions at the proposed repository site. The papers included in this volume represent a subset of the papers presented at the Fallen Leaf Lake Conference and cover a broad spectrum of detail and breadth in a subject that reflects the diverse research interests of the conference participants. These papers provide an insightful look into the current status of geochemical modeling and illustrate how various geochemical modeling codes have been applied to problems of geochemical interest. The emphasis of these papers includes traditional geochemical modeling studies of individual geochemical systems, the mathematical and theoretical development and refinement of new modeling capabilities, and enhancements of data bases on which the computations are based. The papers in this proceedings volume have been organized into the following four areas: Geochemical Model Development, Hydrothermal and Geothermal Systems, Sedimentary and Low Temperature Environments, and Data Base Development. The participants of this symposium and a complete list of the talks presented are listed in the appendices.

  9. TAPIR--Finnish national geochemical baseline database.

    Science.gov (United States)

    Jarva, Jaana; Tarvainen, Timo; Reinikainen, Jussi; Eklund, Mikael

    2010-09-15

    In Finland, a Government Decree on the Assessment of Soil Contamination and Remediation Needs has generated a need for reliable and readily accessible data on geochemical baseline concentrations in Finnish soils. According to the Decree, baseline concentrations, referring both to the natural geological background concentrations and the diffuse anthropogenic input of substances, shall be taken into account in the soil contamination assessment process. This baseline information is provided in a national geochemical baseline database, TAPIR, that is publicly available via the Internet. Geochemical provinces with elevated baseline concentrations were delineated to provide regional geochemical baseline values. The nationwide geochemical datasets were used to divide Finland into geochemical provinces. Several metals (Co, Cr, Cu, Ni, V, and Zn) showed anomalous concentrations in seven regions that were defined as metal provinces. Arsenic did not follow a similar distribution to any other elements, and four arsenic provinces were separately determined. Nationwide geochemical datasets were not available for some other important elements such as Cd and Pb. Although these elements are included in the TAPIR system, their distribution does not necessarily follow the ones pre-defined for metal and arsenic provinces. Regional geochemical baseline values, presented as upper limit of geochemical variation within the region, can be used as trigger values to assess potential soil contamination. Baseline values have also been used to determine upper and lower guideline values that must be taken into account as a tool in basic risk assessment. If regional geochemical baseline values are available, the national guideline values prescribed in the Decree based on ecological risks can be modified accordingly. The national geochemical baseline database provides scientifically sound, easily accessible and generally accepted information on the baseline values, and it can be used in various

  10. Basin-scale hydrogeological, geophysical, geochemical and isotopic characterization: an essential tool for building a Decision Support System for the sustainable management of alluvial aquifer systems within the provinces of Milan and Monza-Brianza (Northern Italy

    Directory of Open Access Journals (Sweden)

    Maurizio Gorla

    2016-10-01

    Full Text Available CAP Group is a public company, supplying the municipalities within the provinces of Milan and Monza/Brianza (Northern Italy with the integrated water service: 197 municipalities and more than 2 million users served, 887 wells, 154 wall-mounted tanks and hubs, a water supply network of over 7500 km, from which approximately 250 million cubic metres of water per year are withdrawn. The drinking water supply comes exclusively from groundwater resources, circulating in several overlapping aquifer systems. Basin-scale water resource management, as required by the European Water Framework Directive (2000/60/EC, is an extremely complex task. In view of this backdrop, CAP is currently developing a project called Infrastructural Aqueduct Plan that relies on a Decision Support System approach. The paper describes the preliminary steps concerning the design of a prototype Decision Support System aiming at the management of groundwater resources on a basin scale (Ticino and Adda rivers area. CAP Group Decision Support System is intended to be a package allowing for water resource assessment, identification of boundary conditions, climatic driving forces and demographic pressures, simulation and investigation of future forecasts and comparison of alternative policy measures. The project has been designed in steps including Geodatabase building, geographic information system (GIS analysis (including multilayer analysis and numerical modelling. The data collected in the geodatabase were analyzed to design GIS quantitative and qualitative thematic maps in order to perform the multilayer analysis of current and future state and impacts, for providing the decision maker with a comprehensive picture of the water system. The multilayer analysis relies on specific indicators based on some quantitative and qualitative data: hydrogeological, chemical, isotopic, soil use and hazards, climatic and demographic. Each parameter belonging to these macro areas were

  11. Rapid geophysical surveyor

    International Nuclear Information System (INIS)

    Roybal, L.G.; Carpenter, G.S.; Josten, N.E.

    1993-01-01

    The Rapid Geophysical Surveyor (RGS) is a system designed to rapidly and economically collect closely-spaced geophysical data used for characterization of Department of Energy (DOE) waste sites. Geophysical surveys of waste sites are an important first step in the remediation and closure of these sites; especially older sties where historical records are inaccurate and survey benchmarks have changed due to refinements in coordinate controls and datum changes. Closely-spaced data are required to adequately differentiate pits, trenches, and soil vault rows whose edges may be only a few feet from each other. A prototype vehicle designed to collect magnetic field data was built at the Idaho national Engineering Laboratory (INEL) during the summer of 1992. The RGS was one of several projects funded by the Buried Waste Integrated Demonstration (BWID) program. This vehicle was demonstrated at the Subsurface Disposal Area (SDA) within the Radioactive Waste Management Complex (RWMC) on the INEL in September of 1992. Magnetic data were collected over two areas in the SDA, with a total survey area of about 1.7 acres. Data were collected at a nominal density of 2 1/2 inches along survey lines spaced 1 foot apart. Over 350,000 data points were collected over a 6 day period corresponding to about 185 man-days using conventional ground survey techniques. This report documents the design and demonstration of the RGS concept including the presentation of magnetic data collected at the SDA. The surveys were able to show pit and trench boundaries and determine details of their spatial orientation never before achieved

  12. Responsibilities, opportunities and challenges in geophysical exploration

    International Nuclear Information System (INIS)

    Rytle, R.J.

    1982-01-01

    Geophysical exploration for engineering purposes is conducted to decrease the risk in encountering site uncertainties in construction of underground facilities. Current responsibilities, opportunities and challenges for those with geophysical expertise are defined. These include: replacing the squiggly line format, developing verification sites for method evaluations, applying knowledge engineering and assuming responsibility for crucial national problems involving rock mechanics expertise

  13. Geophysical Data Sets in GeoMapApp

    Science.gov (United States)

    Goodwillie, A. M.

    2017-12-01

    GeoMapApp (http://www.geomapapp.org), a free map-based data tool developed at Lamont-Doherty Earth Observatory, provides access to hundreds of integrated geoscience data sets that are useful for geophysical studies. Examples include earthquake and volcano catalogues, gravity and magnetics data, seismic velocity tomographic models, geological maps, geochemical analytical data, lithospheric plate boundary information, geodetic velocities, and high-resolution bathymetry and land elevations. Users can also import and analyse their own data files. Data analytical functions provide contouring, shading, profiling, layering and transparency, allowing multiple data sets to be seamlessly compared. A new digitization and field planning portal allow stations and waypoints to be generated. Sessions can be saved and shared with colleagues and students. In this eLightning presentation we will demonstrate some of GeoMapApp's capabilities with a focus upon subduction zones and tectonics. In the attached screen shot of the Cascadia margin, the contoured depth to the top of the subducting Juan de Fuca slab is overlain on a shear wave velocity depth slice. Geochemical data coloured on Al2O3 and scaled on MgO content is shown as circles. The stack of data profiles was generated along the white line.

  14. Geochemical Constraints for Mercury's PCA-Derived Geochemical Terranes

    Science.gov (United States)

    Stockstill-Cahill, K. R.; Peplowski, P. N.

    2018-05-01

    PCA-derived geochemical terranes provide a robust, analytical means of defining these terranes using strictly geochemical inputs. Using the end members derived in this way, we are able to assess the geochemical implications for Mercury.

  15. Critical zone architecture and processes: a geophysical perspective

    Science.gov (United States)

    Holbrook, W. S.

    2016-12-01

    The "critical zone (CZ)," Earth's near-surface layer that reaches from treetop to bedrock, sustains terrestrial life by storing water and producing nutrients. Despite is central importance, however, the CZ remains poorly understood, due in part to the complexity of interacting biogeochemical and physical processes that take place there, and in part due to the difficulty of measuring CZ properties and processes at depth. Major outstanding questions include: What is the architecture of the CZ? How does that architecture vary across scales and across gradients in climate, lithology, topography, biology and regional states of stress? What processes control the architecture of the CZ? At what depth does weathering initiate, and what controls the rates at which it proceeds? Based on recent geophysical campaigns at seven Critical Zone Observatory (CZO) sites and several other locations, a geophysical perspective on CZ architecture and processes is emerging. CZ architecture can be usefully divided into four layers, each of which has distinct geophysical properties: soil, saprolite, weathered bedrock and protolith. The distribution of those layers across landscapes varies depending on protolith composition and internal structure, topography, climate (P/T) and the regional state of stress. Combined observations from deep CZ drilling, geophysics and geochemistry demonstrate that chemical weathering initiates deep in the CZ, in concert with mechanical weathering (fracturing), as chemical weathering appears concentrated along fractures in borehole walls. At the Calhoun CZO, the plagioclase weathering front occurs at nearly 40 m depth, at the base of a 25-m-thick layer of weathered bedrock. The principal boundary in porosity, however, occurs at the saprolite/weathered bedrock boundary: porosity decreases over an order of magnitude, from 50% to 5% over an 8-m-thick zone at the base of saprolite. Porosity in weathered bedrock is between 2-5%. Future progress will depend on (1

  16. European Lithospheric Mantle; geochemical, petrological and geophysical processes

    Science.gov (United States)

    Ntaflos, Th.; Puziewicz, J.; Downes, H.; Matusiak-Małek, M.

    2017-04-01

    The second European Mantle Workshop occurred at the end of August 2015, in Wroclaw, Poland, attended by leading scientists in the study the lithospheric mantle from around the world. It built upon the results of the first European Mantle Workshop (held in 2007, in Ferrara, Italy) published in the Geological Society of London Special Publication 293 (Coltorti & Gregoire, 2008).

  17. 36 CFR 902.59 - Geological and geophysical information.

    Science.gov (United States)

    2010-07-01

    ... 36 Parks, Forests, and Public Property 3 2010-07-01 2010-07-01 false Geological and geophysical information. 902.59 Section 902.59 Parks, Forests, and Public Property PENNSYLVANIA AVENUE DEVELOPMENT... Geological and geophysical information. Any geological or geophysical information and data (including maps...

  18. Geochemical exploration for uranium

    International Nuclear Information System (INIS)

    1988-01-01

    This Technical Report is designed mainly to introduce the methods and techniques of uranium geochemical exploration to exploration geologists who may not have had experience with geochemical exploration methods in their uranium programmes. The methods presented have been widely used in the uranium exploration industry for more than two decades. The intention has not been to produce an exhaustive, detailed manual, although detailed instructions are given for a field and laboratory data recording scheme and a satisfactory analytical method for the geochemical determination of uranium. Rather, the intention has been to introduce the concepts and methods of uranium exploration geochemistry in sufficient detail to guide the user in their effective use. Readers are advised to consult general references on geochemical exploration to increase their understanding of geochemical techniques for uranium

  19. Advances in geophysics

    CERN Document Server

    Sato, Haruo

    2013-01-01

    The critically acclaimed serialized review journal for over 50 years, Advances in Geophysics is a highly respected publication in the field of geophysics. Since 1952, each volume has been eagerly awaited, frequently consulted, and praised by researchers and reviewers alike. Now in its 54th volume, it contains much material still relevant today--truly an essential publication for researchers in all fields of geophysics.Key features: * Contributions from leading authorities * Informs and updates on all the latest developments in the field

  20. Proceedings of 2. Brazilian Geochemical Congress

    International Nuclear Information System (INIS)

    1989-01-01

    Some works about geochemistry are presented, including themes about geochemical exploration, lithogeochemistry and isotope geochemistry, environmental geochemistry, analytical geochemistry, geochemistry of carbonatites and rare earth elements and organic geochemistry. (C.G.C.) [pt

  1. Autonomous cloud based site monitoring through hydro geophysical data assimilation, processing and result delivery

    Science.gov (United States)

    Versteeg, R.; Johnson, D. V.; Rodzianko, A.; Zhou, H.; Dafflon, B.; Leger, E.; de Kleine, M.

    2017-12-01

    Understanding of processes in the shallow subsurface requires that geophysical, biogeochemical, hydrological and remote sensing datasets are assimilated, processed and interpreted. Multiple enabling software capabilities for process understanding have been developed by the science community. These include information models (ODM2), reactive transport modeling (PFLOTRAN, Modflow, CLM, Landlab), geophysical inversion (E4D, BERT), parameter estimation (PEST, DAKOTA), visualization (ViSiT, Paraview, D3, QGIS) as well as numerous tools written in python and R for petrophysical mapping, stochastic modeling, data analysis and so on. These capabilities use data collected using sensors and analytical tools developed by multiple manufacturers which produce many different measurements. While scientists obviously leverage tools, capabilities and lessons learned from one site at other sites, the current approach to site characterization and monitoring is very labor intensive and does not scale well. Our objective is to be able to monitor many (hundreds - thousands) of sites. This requires that monitoring can be done in a near time, affordable, auditable and essentially autonomous manner. For this we have developed a modular vertically integrated cloud based software framework which was designed from the ground up for effective site and process monitoring. This software framework (PAF - Predictive Assimilation Framework) is multitenant software and provides automation of data ingestion, processing and visualization of hydrological, geochemical and geophysical (ERT/DTS) data. The core organizational element of PAF is a project/user one in which capabilities available to users are controlled by a combination of available data and access permissions. All PAF capabilities are exposed through APIs, making it easy to quickly add new components. PAF is fully integrated with newly developed autonomous electrical geophysical hardware and thus allows for automation of electrical

  2. Fundamentals of Geophysics

    Science.gov (United States)

    Lowrie, William

    1997-10-01

    This unique textbook presents a comprehensive overview of the fundamental principles of geophysics. Unlike most geophysics textbooks, it combines both the applied and theoretical aspects to the subject. The author explains complex geophysical concepts using abundant diagrams, a simplified mathematical treatment, and easy-to-follow equations. After placing the Earth in the context of the solar system, he describes each major branch of geophysics: gravitation, seismology, dating, thermal and electrical properties, geomagnetism, paleomagnetism and geodynamics. Each chapter begins with a summary of the basic physical principles, and a brief account of each topic's historical evolution. The book will satisfy the needs of intermediate-level earth science students from a variety of backgrounds, while at the same time preparing geophysics majors for continued study at a higher level.

  3. Reconnaissance Geochemical Study

    African Journals Online (AJOL)

    distribution patterns. The geochemical distribution maps of the elements reveal that Cu, Pb, Zn, Co, Sc, Ni, Cr, .... After filtration, the leached solutions were diluted with ultra ...... some other rare earth elements in the study area. The occurrence ...

  4. Serious games for Geophysics

    Science.gov (United States)

    Lombardo, Valerio; Rubbia, Giuliana

    2015-04-01

    Childhood stage is indispensable in the education of human beings and especially critical to arise scientific interest in children. We discuss the participatory design of a didactic videogame, i.e. a "serious" game to teach geophysics and Earth sciences to high and low-school students. Geophysics is the application of the laws and techniques of physics to uncover knowledge about the earth's dynamic processes and subsurface structure. It explores phenomena such as earthquakes, volcanoes, tsunamis to improve our understanding of the earth's physical processes and our ability to predict reoccurrences. Effective mitigation of risks from catastrophic geologic hazards requires knowledge and understanding of local geology and geologic processes. Scientific outreach can be defined as discourse activity, whose main objective is to communicate some knowledge previously produced in scientific contexts to a non-expert massive audience. One of the difficulties science educators need to overcome is to explain specific concepts from a given discipline in a language simple and understandable for their audience. Digital games today play a large role in young people's lives. Games are directly connected to the life of today's adolescents. Therefore, digital games should be included and broached as a subject in the classroom. The ardor and enthusiasm that digital games evoke in teenagers has indeed brought many researchers, school leaders and teachers to the question "how video games" can be used to engage young people and support their learning inside the classroom. Additionally, studies have shown that digital games can enhance various skills such as the ability to concentrate, stamina, tactical aptness, anticipatory thinking, orientation in virtual spaces, and deductive reasoning. Thus, videogames become an effective didactic mechanism and should have a place in the classroom. The project aims to explore the potentials of entertainment technologies in educational processes

  5. Sustainable Geophysical Observatory Networks

    Science.gov (United States)

    Willemann, R. J.; Lerner-Lam, A.; Aster, R.; Beck, S.; Ekstrom, G.; Nyblade, A.; Sandvol, E.

    2007-05-01

    Geophysical networks are defined not only by their technical specifications, but also by the characteristics and needs of the communities that use them. Growing populations supported by more elaborate urban infrastructure with its fine-grained socio-economic interdependencies and relying on global and regional connections for sustainability make new demands for natural hazard risk management. Taking advantage of advances in the underlying science to provide society with accurate risk assessments often requires higher fidelity measurements, entirely new types of observations, and an evolutionary sense of data products and information management. Engineering a high-tech system to address stakeholder needs is difficult, and designing for unpredictable developments requires an emphasis on adaptation. Thus, it is essential to promote formation of organizations or communities that can support evolution of a technological system, imagine new uses, and develop the societal relationships that sustain operations and provide capital for improvement. The owners must have a deep understanding of why the system works in particular ways and how to manage data products for the benefits of stakeholders. To be effective, community promotion must be sustained over a longer period of time than required to build a network and should be aimed at integrating the community into worldwide partnerships. Practices that can promote community formation if they are sustained include repeated training and scientific exchange workshops, extended visits by experts and staff at all levels to and from countries where networks are installed, mechanisms that make timely upgrades realistically possible, and routine exchange and wide dissemination of data in all directions. The combination of international research and educational collaborations, supported by open data exchange, with regionalized and specific assessments of local stakeholder needs and concerns, provides a sustainable model for

  6. Review of geophysical characterization methods used at the Hanford Site

    Energy Technology Data Exchange (ETDEWEB)

    GV Last; DG Horton

    2000-03-23

    This paper presents a review of geophysical methods used at Hanford in two parts: (1) shallow surface-based geophysical methods and (2) borehole geophysical methods. This review was not intended to be ``all encompassing'' but should represent the vast majority (>90% complete) of geophysical work conducted onsite and aimed at hazardous waste investigations in the vadose zone and/or uppermost groundwater aquifers. This review did not cover geophysical methods aimed at large-scale geologic structures or seismicity and, in particular, did not include those efforts conducted in support of the Basalt Waste Isolation Program. This review focused primarily on the more recent efforts.

  7. Review of geophysical characterization methods used at the Hanford Site

    International Nuclear Information System (INIS)

    GV Last; DG Horton

    2000-01-01

    This paper presents a review of geophysical methods used at Hanford in two parts: (1) shallow surface-based geophysical methods and (2) borehole geophysical methods. This review was not intended to be ''all encompassing'' but should represent the vast majority (>90% complete) of geophysical work conducted onsite and aimed at hazardous waste investigations in the vadose zone and/or uppermost groundwater aquifers. This review did not cover geophysical methods aimed at large-scale geologic structures or seismicity and, in particular, did not include those efforts conducted in support of the Basalt Waste Isolation Program. This review focused primarily on the more recent efforts

  8. Evaluation of uranium geochemical anomalies in the Charlotte 10 x 20 NTMS quadrangle

    International Nuclear Information System (INIS)

    Carpenter, R.H.

    1981-11-01

    This report contains a synthesis of published geological, geophysical, and geochemical information for portions of Cabarrus and Rowan Counties, NC, where uranium geochemical anomalies have been described by Heffner and Ferguson (1978). The results of a ground radiation survey in selected areas are also described. Based on an evaluation of published information and the data obtained in the field study, conclusions are made regarding the possible occurrence of uranium concentration. Recommendations for detailed surveys in certain areas are also presented

  9. SAGE (Summer of Applied Geophysical Experience): Learning Geophysics by Doing Geophysics

    Science.gov (United States)

    Jiracek, G. R.; Baldridge, W. S.; Biehler, S.; Braile, L. W.; Ferguson, J. F.; Gilpin, B. E.; Pellerin, L.

    2005-12-01

    SAGE, a field-based educational program in applied geophysical methods has been an REU site for 16 years and completed its 23rd year of operation in July 2005. SAGE teaches the major geophysical exploration methods (including seismics, gravity, magnetics, and electromagnetics) and applies them to the solution of specific local and regional geologic problems. These include delineating buried hazardous material; mapping archaeological sites; and studying the structure, tectonics, and water resources of the Rio Grande rift in New Mexico. Nearly 600 graduates, undergraduates, and professionals have attended SAGE since 1983. Since 1990 REU students have numbered 219 coming from dozens of different campuses. There have been 124 underrepresented REU students including 100 women, 14 Hispanics, 7 Native Americans, and 3 African Americans. Tracking of former REU students has revealed that 81% have gone on to graduate school. Keys to the success of SAGE are hands-on immersion in geophysics for one month and a partnership between academia, industry, and a federal laboratory. Successful approaches at SAGE include: 1) application of the latest equipment by all students; 2) continued updating of equipment, computers, and software by organizing universities and industry affiliates; 3) close ties with industry who provide supplemental instruction, furnish new equipment and software, and alert students to the current industry trends and job opportunities; 4) two-team, student data analysis structure that simultaneously addresses specific geophysical techniques and their integration; and 5) oral and written reports patterned after professional meetings and journals. An eight member, 'blue ribbon' advisory panel from academia, industry, and the federal government has been set up to maintain the vitality of SAGE by addressing such issues as funding, new faculty, organization, and vision. SAGE is open to students from any university (or organization) with backgrounds including

  10. Application of multiple geochemical indicators, including the stable isotopes of water, to differentiate water quality evolution in a region influenced by various agricultural practices and domestic wastewater treatment and disposal

    International Nuclear Information System (INIS)

    Butler, Thomas W.

    2007-01-01

    Spatial and temporal variations in groundwater chemistry indicate that the use of low TDS lake water for irrigation, on land located just south of the City of Dixon, Solano County, California, is primarily responsible for improving groundwater quality with regards to salts. The stable isotopes of water further support this finding and suggest that TDS concentrations decrease as groundwater evolves to a more highly evaporated state. This seemingly contradictory finding was primarily attributed to infiltration of low TDS Lake Berryessa surface water, which has an isotopic signature indicative of an evaporated source and is used extensively for irrigation in the area, mixing with poorer quality locally recharged shallow groundwater. Geochemical modeling using the program PHREEQC further supports the anthropogenic aquifer freshening hypotheses through computed reductions in the saturation state of carbonate minerals in the vicinity of land irrigated by lake derived water, which is undersaturated with regards to modeled carbonates. Additionally, δ 18 O and δ 2 H were found to be useful in estimating climatic variables such as temperature and humidity, illustrating the potential for applying these models in hydrologic investigations within the area. It was however found that USDA NRCS soils data and measured water chemistry were not well correlated and thus the use of soils classifications to assess potential groundwater quality impacts was of limited utility

  11. Proceedings of 13. International Geochemical Exploration Symposium. 2. Brazilian Geochemical Congress

    International Nuclear Information System (INIS)

    1989-01-01

    Some works about geochemistry are presented, including themes about geochemical exploration, lithogeochemistry and isotope geochemistry, environmental geochemistry, analyical geochemistry, geochemistry of carbonatites and rare earth elements and organic geochemistry. (C.G.C.) [pt

  12. Radioactivity and geophysics

    International Nuclear Information System (INIS)

    Radvanyi, P.

    1992-01-01

    The paper recalls a few steps of the introduction of radioactivity in geophysics and astrophysics: contribution of radioelements to energy balance of the Earth, age of the Earth based on radioactive disintegration and the discovery of cosmic radiations

  13. Geophysical Research Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Geophysical Research Facility (GRF) is a 60 ft long × 22 ft wide × 7 ft deep concrete basin at CRREL for fresh or saltwater investigations and can be temperature...

  14. Methods for geochemical analysis

    Science.gov (United States)

    Baedecker, Philip A.

    1987-01-01

    The laboratories for analytical chemistry within the Geologic Division of the U.S. Geological Survey are administered by the Office of Mineral Resources. The laboratory analysts provide analytical support to those programs of the Geologic Division that require chemical information and conduct basic research in analytical and geochemical areas vital to the furtherance of Division program goals. Laboratories for research and geochemical analysis are maintained at the three major centers in Reston, Virginia, Denver, Colorado, and Menlo Park, California. The Division has an expertise in a broad spectrum of analytical techniques, and the analytical research is designed to advance the state of the art of existing techniques and to develop new methods of analysis in response to special problems in geochemical analysis. The geochemical research and analytical results are applied to the solution of fundamental geochemical problems relating to the origin of mineral deposits and fossil fuels, as well as to studies relating to the distribution of elements in varied geologic systems, the mechanisms by which they are transported, and their impact on the environment.

  15. Geophysical borehole logging

    International Nuclear Information System (INIS)

    McCann, D.; Barton, K.J.; Hearn, K.

    1981-08-01

    Most of the available literature on geophysical borehole logging refers to studies carried out in sedimentary rocks. It is only in recent years that any great interest has been shown in geophysical logging in boreholes in metamorphic and igneous rocks following the development of research programmes associated with geothermal energy and nuclear waste disposal. This report is concerned with the programme of geophysical logging carried out on the three deep boreholes at Altnabreac, Caithness, to examine the effectiveness of these methods in crystalline rock. Of particular importance is the assessment of the performance of the various geophysical sondes run in the boreholes in relation to the rock mass properties. The geophysical data can be used to provide additional in-situ information on the geological, hydrogeological and engineering properties of the rock mass. Fracturing and weathering in the rock mass have a considerable effect on both the design parameters for an engineering structure and the flow of water through the rock mass; hence, the relation between the geophysical properties and the degree of fracturing and weathering is examined in some detail. (author)

  16. Introduction to the JEEG Agricultural Geophysics Special Issue

    Science.gov (United States)

    Allred, Barry J.; Smith, Bruce D.

    2010-01-01

    Near-surface geophysical methods have become increasingly important tools in applied agricultural practices and studies. The great advantage of geophysical methods is their potential rapidity, low cost, and spatial continuity when compared to more traditional methods of assessing agricultural land, such as sample collection and laboratory analysis. Agricultural geophysics investigations commonly focus on obtaining information within the soil profile, which generally does not extend much beyond 2 meters beneath the ground surface. Although the depth of interest oftentimes is rather shallow, the area covered by an agricultural geophysics survey can vary widely in scale, from experimental plots (10 s to 100 s of square meters), to farm fields (10 s to 100 s of hectares), up to the size of watersheds (10 s to 100 s of square kilometers). To date, three predominant methods—resistivity, electromagnetic induction (EMI), and ground-penetrating radar (GPR)—have been used to obtain surface-based geophysical measurements within agricultural settings. However, a recent conference on agricultural geophysics (Bouyoucos Conference on Agricultural Geophysics, September 8–10, 2009, Albuquerque, New Mexico; www.ag-geophysics.org) illustrated that other geophysical methods are being applied or developed. These include airborne electromagnetic induction, magnetometry, seismic, and self-potential methods. Agricultural geophysical studies are also being linked to ground water studies that utilize deeper penetrating geophysical methods than normally used.

  17. A ''model'' geophysics program

    International Nuclear Information System (INIS)

    Nyquist, J.E.

    1994-01-01

    In 1993, I tested a radio-controlled airplane designed by Jim Walker of Brigham Young University for low-elevation aerial photography. Model-air photography retains most of the advantages of standard aerial photography --- the photographs can be used to detect lineaments, to map roads and buildings, and to construct stereo pairs to measure topography --- and it is far less expensive. Proven applications on the Oak Ridge Reservation include: updating older aerial records to document new construction; using repeated overflights of the same area to capture seasonal changes in vegetation and the effects of major storms; and detecting waste trench boundaries from the color and character of the overlying grass. Aerial photography is only one of many possible applications of radio-controlled aircraft. Currently, I am funded by the Department of Energy's Office of Technology Development to review the state of the art in microavionics, both military and civilian, to determine ways this emerging technology can be used for environmental site characterization. Being particularly interested in geophysical applications, I am also collaborating with electrical engineers at Oak Ridge National Laboratory to design a model plane that will carry a 3-component flux-gate magnetometer and a global positioning system, which I hope to test in the spring of 1994

  18. Karoo airborne geophysical survey

    International Nuclear Information System (INIS)

    Cole, D.J.; Stettler, E.H.

    1984-01-01

    Thirty four uranium anomalies were selected for ground follow-up from the analogue spectrometer records of Block 4 of the Karoo Airborne Geophysical Survey. The anomalies were plotted on 1:50 000 scale topographic maps and to 1:250 000 scale maps which are included in this report. The anomaly co-ordinates are tabulated together with the farms on which they occur. Results of the ground follow-up of the aerial anomalies are described. Twenty two anomalies are related to uranium mineralisation of which seventeen occur over baked mudstone adjacent to a dolerite intrusion. Five are located over fluvial channel sandstone of the Beaufort Group and subsurface mineralised sandstone may be present. The other twelve anomalies are spurious. Of the anomalies located over baked mudstone, fifteen emanate from ferruginous mudstone of the Whitehill Formation west of longitude 21 degrees 15 minutes. One of the two remaining anomalies over baked mudstone occurs over the Prince Albert Formation and the other anomaly is over baked mudstone and calcareous nodules of the Beaufort Group. The general low uranium values (less than 355 ppm eU3O8) render the occurrences uneconomic

  19. Jesuit Geophysical Observatories

    Science.gov (United States)

    Udias, Agustin; Stauder, William

    Jesuits have had ah interest in observing and explaining geophysical phenomena since this religious order, the Society of Jesus, was founded by Ignatius of Loyola in 1540. Three principal factors contributed to this interest: their educational work in colleges and universities, their missionary endeavors to remote lands where they observed interesting and often as yet undocumented natural phenomena, and a network of communication that brought research of other Jesuits readily to their awareness.One of the first and most important Jesuit colleges was the Roman College (today the Gregorian University) founded in 1551 in Rome, which served as a model for many other universities throughout the world. By 1572, Christopher Clavius (1537-1612), professor of mathematics at the Roman College, had already initiated an important tradition of Jesuit research by emphasizing applied mathematics and insisting on the need of serious study of mathematics in the program of studies in the humanities. In 1547 he directed a publication of Euclid's work with commentaries, and published several treatises on mathematics, including Arithmetica Practica [1585], Gnomonicae [1581], and Geometrica Practica [1606]. Clavius was also a Copernican and supported his friend Galileo when he announced the discovery of the satellites of Jupiter.

  20. Geochemical Investigations of Groundwater Stability

    International Nuclear Information System (INIS)

    Bath, Adrian

    2006-05-01

    The report describes geochemical parameters and methods that provide information about the hydrodynamic stability of groundwaters in low permeability fractured rocks that are potential hosts for radioactive waste repositories. Hydrodynamic stability describes the propensity for changes in groundwater flows over long timescales, in terms of flow rates and flow directions. Hydrodynamic changes may also cause changes in water compositions, but the related issue of geochemical stability of a potential repository host rock system is outside the scope of this report. The main approaches to assessing groundwater stability are numerical modelling, measurement and interpretation of geochemical indicators in groundwater compositions, and analyses and interpretations of secondary minerals and fluid inclusions in these minerals. This report covers the latter two topics, with emphasis on geochemical indicators. The extent to which palaeohydrogeology and geochemical stability indicators have been used in past safety cases is reviewed. It has been very variable, both in terms of the scenarios considered, the stability indicators considered and the extent to which the information was explicitly or implicitly used in assessing FEPs and scenarios in the safety cases. Geochemical indicators of hydrodynamic stability provide various categories of information that are of hydrogeological relevance. Information about groundwater mixing, flows and water sources is potentially provided by the total salinity of groundwaters, their contents of specific non-reactive solutes (principally chloride) and possibly of other solutes, the stable isotopic ratio of water, and certain characteristics of secondary minerals and fluid inclusions. Information pertaining directly to groundwater ages and the timing of water and solute movements is provided by isotopic systems including tritium, carbon-14, chlorine-36, stable oxygen and hydrogen isotopes, uranium isotopes and dissolved mobile gases in

  1. Geochemical Investigations of Groundwater Stability

    Energy Technology Data Exchange (ETDEWEB)

    Bath, Adrian [Intellisci Ltd., Loughborough (United Kingdom)

    2006-05-15

    The report describes geochemical parameters and methods that provide information about the hydrodynamic stability of groundwaters in low permeability fractured rocks that are potential hosts for radioactive waste repositories. Hydrodynamic stability describes the propensity for changes in groundwater flows over long timescales, in terms of flow rates and flow directions. Hydrodynamic changes may also cause changes in water compositions, but the related issue of geochemical stability of a potential repository host rock system is outside the scope of this report. The main approaches to assessing groundwater stability are numerical modelling, measurement and interpretation of geochemical indicators in groundwater compositions, and analyses and interpretations of secondary minerals and fluid inclusions in these minerals. This report covers the latter two topics, with emphasis on geochemical indicators. The extent to which palaeohydrogeology and geochemical stability indicators have been used in past safety cases is reviewed. It has been very variable, both in terms of the scenarios considered, the stability indicators considered and the extent to which the information was explicitly or implicitly used in assessing FEPs and scenarios in the safety cases. Geochemical indicators of hydrodynamic stability provide various categories of information that are of hydrogeological relevance. Information about groundwater mixing, flows and water sources is potentially provided by the total salinity of groundwaters, their contents of specific non-reactive solutes (principally chloride) and possibly of other solutes, the stable isotopic ratio of water, and certain characteristics of secondary minerals and fluid inclusions. Information pertaining directly to groundwater ages and the timing of water and solute movements is provided by isotopic systems including tritium, carbon-14, chlorine-36, stable oxygen and hydrogen isotopes, uranium isotopes and dissolved mobile gases in

  2. Geochemical prospecting in Guiana

    International Nuclear Information System (INIS)

    Coulomb, R.

    1957-01-01

    During the last few years geochemical prospecting techniques have become common usage in the field of mineral deposit prospecting. The real scope of these methods lies in their use in the prospecting of large areas. The most promising use of the geochemistry and hydro-geochemistry of uranium is in heavily forested tropical territories, with few outcrops, where radiometry is strongly handicapped. (author) [fr

  3. Geophysical techniques for detecting magmas and high-temperature fluids. Their application to the Onikobe-Narugo volcanic region and the southern Kii Peninsula

    International Nuclear Information System (INIS)

    Asamori, Koichi; Umeda, Koji

    2005-01-01

    The effects of volcanism on the geological environments include a dynamic destruction and subsidence of basement rocks, caused by the intrusion and eruption of magma. To ensure the long-term stability of geological disposal system, a possibility of renewed volcanism at the site might be examined based on the geotectonic data of the deep underground using geophysical and geochemical approaches. This paper describes an overview of geophysical approaches for detecting magmas and/or high temperature fluids related to volcanism within the crust and uppermost mantle. Moreover, we present the images of the seismic velocity and electrical resistivity structure beneath the Onikobe-Narugo volcanic region and the southern Kii Peninsula, carried out in JNC's R and D program. (author)

  4. Alaska Geochemical Database (AGDB)-Geochemical data for rock, sediment, soil, mineral, and concentrate sample media

    Science.gov (United States)

    Granitto, Matthew; Bailey, Elizabeth A.; Schmidt, Jeanine M.; Shew, Nora B.; Gamble, Bruce M.; Labay, Keith A.

    2011-01-01

    The Alaska Geochemical Database (AGDB) was created and designed to compile and integrate geochemical data from Alaska in order to facilitate geologic mapping, petrologic studies, mineral resource assessments, definition of geochemical baseline values and statistics, environmental impact assessments, and studies in medical geology. This Microsoft Access database serves as a data archive in support of present and future Alaskan geologic and geochemical projects, and contains data tables describing historical and new quantitative and qualitative geochemical analyses. The analytical results were determined by 85 laboratory and field analytical methods on 264,095 rock, sediment, soil, mineral and heavy-mineral concentrate samples. Most samples were collected by U.S. Geological Survey (USGS) personnel and analyzed in USGS laboratories or, under contracts, in commercial analytical laboratories. These data represent analyses of samples collected as part of various USGS programs and projects from 1962 to 2009. In addition, mineralogical data from 18,138 nonmagnetic heavy mineral concentrate samples are included in this database. The AGDB includes historical geochemical data originally archived in the USGS Rock Analysis Storage System (RASS) database, used from the mid-1960s through the late 1980s and the USGS PLUTO database used from the mid-1970s through the mid-1990s. All of these data are currently maintained in the Oracle-based National Geochemical Database (NGDB). Retrievals from the NGDB were used to generate most of the AGDB data set. These data were checked for accuracy regarding sample location, sample media type, and analytical methods used. This arduous process of reviewing, verifying and, where necessary, editing all USGS geochemical data resulted in a significantly improved Alaska geochemical dataset. USGS data that were not previously in the NGDB because the data predate the earliest USGS geochemical databases, or were once excluded for programmatic reasons

  5. Inverse problems of geophysics

    International Nuclear Information System (INIS)

    Yanovskaya, T.B.

    2003-07-01

    This report gives an overview and the mathematical formulation of geophysical inverse problems. General principles of statistical estimation are explained. The maximum likelihood and least square fit methods, the Backus-Gilbert method and general approaches for solving inverse problems are discussed. General formulations of linearized inverse problems, singular value decomposition and properties of pseudo-inverse solutions are given

  6. Geochemical modeling: a review

    International Nuclear Information System (INIS)

    Jenne, E.A.

    1981-06-01

    Two general families of geochemical models presently exist. The ion speciation-solubility group of geochemical models contain submodels to first calculate a distribution of aqueous species and to secondly test the hypothesis that the water is near equilibrium with particular solid phases. These models may or may not calculate the adsorption of dissolved constituents and simulate the dissolution and precipitation (mass transfer) of solid phases. Another family of geochemical models, the reaction path models, simulates the stepwise precipitation of solid phases as a result of reacting specified amounts of water and rock. Reaction path models first perform an aqueous speciation of the dissolved constituents of the water, test solubility hypotheses, then perform the reaction path modeling. Certain improvements in the present versions of these models would enhance their value and usefulness to applications in nuclear-waste isolation, etc. Mass-transfer calculations of limited extent are certainly within the capabilities of state-of-the-art models. However, the reaction path models require an expansion of their thermodynamic data bases and systematic validation before they are generally accepted

  7. Geochemical modeling: a review

    Energy Technology Data Exchange (ETDEWEB)

    Jenne, E.A.

    1981-06-01

    Two general families of geochemical models presently exist. The ion speciation-solubility group of geochemical models contain submodels to first calculate a distribution of aqueous species and to secondly test the hypothesis that the water is near equilibrium with particular solid phases. These models may or may not calculate the adsorption of dissolved constituents and simulate the dissolution and precipitation (mass transfer) of solid phases. Another family of geochemical models, the reaction path models, simulates the stepwise precipitation of solid phases as a result of reacting specified amounts of water and rock. Reaction path models first perform an aqueous speciation of the dissolved constituents of the water, test solubility hypotheses, then perform the reaction path modeling. Certain improvements in the present versions of these models would enhance their value and usefulness to applications in nuclear-waste isolation, etc. Mass-transfer calculations of limited extent are certainly within the capabilities of state-of-the-art models. However, the reaction path models require an expansion of their thermodynamic data bases and systematic validation before they are generally accepted.

  8. Evaluation of geophysical borehole studies

    International Nuclear Information System (INIS)

    Brotzen, O.; Duran, O.; Magnusson, K.Aa.

    Four studies concerning geophysical investigations and TV inspection in boreholes in connection with KBS studies at Finnsjoe, Karlshamn, Kraakemaala and Stripa and PRAV's studies at Studsvik have been evaluated. This has led to proposals concerning the choice of instruments and methods for future studies and a review of future work required. The evaluation has shown that the following borehole measurements are of primary interest in the continued work: Determinations of temperature and resistivity of the borehole liquid, resistance and resistivity measurements, SP, Sonic, Caliper and VLF. TV inspection, IP and gamma-gamma should also be included in the arsenal of available test methods.(author)

  9. Geochemical modelling baseline compositions of groundwater

    DEFF Research Database (Denmark)

    Postma, Diederik Jan; Kjøller, Claus; Andersen, Martin Søgaard

    2008-01-01

    and variations in water chemistry that are caused by large scale geochemical processes taking place at the timescale of thousands of years. The most important geochemical processes are ion exchange (Valreas and Aveiro) where freshwater solutes are displacing marine ions from the sediment surface, and carbonate......Reactive transport models, were developed to explore the evolution in groundwater chemistry along the flow path in three aquifers; the Triassic East Midland aquifer (UK), the Miocene aquifer at Valreas (F) and the Cretaceous aquifer near Aveiro (P). All three aquifers contain very old groundwaters...... dissolution (East Midlands, Valreas and Aveiro). Reactive transport models, employing the code PHREEQC, which included these geochemical processes and one-dimensional solute transport were able to duplicate the observed patterns in water quality. These models may provide a quantitative understanding...

  10. Geophysical investigations of the Romuvaara area, Finland

    International Nuclear Information System (INIS)

    Saksa, P.; Paananen, M.

    1991-06-01

    In the study area of Romuvaara, investigations have been carried out during 1987 - 90 with the aim of finding out whether the polyphasically deformed Precambrian gneiss complex is suitable for the final disposal of spent nuclear fuel. The bedrock has been studied by geological, geophysical, geohydrological and geochemical methods. Airborne, ground and borehole geophysical surveys were used in studying the rock type distribution, fracturing and hydraulic conductivity of the bedrock to a depth of one kilometre. Airborne surveys (magnetic, radiometric and two electromagnetic methods) and ground surveys (VLF and VLF-R, magnetic and soil radar methods) were useful in distinguishing the metadiabases, amphibolites and granodiorites from the less magnetized migmatites. The electromagnetic and seismic refraction surveys were used in locating crushed and fractured zones. The rock type distribution was studied by single-hole logging of susceptibility, natural γ radiation and radiometric γ-γ -density. Electrical and acoustic logging served the mapping of fractures and the interpretation of water injection tests. The flow conditions in the boreholes were studied by fluid logging and tube-wave sounding. The rock volume surrounding the boreholes was mapped by borehole radar with a frequency of 22 MHz. The upper parts of the boreholes were also studied by vertical radar profiling (VRP). Larger volumes of rock were mapped by vertical seismic profiling (VSP) using 4 - 5 transmitter shotholes per borehole

  11. Fundamentals of Geophysics

    Science.gov (United States)

    Frohlich, Cliff

    Choosing an intermediate-level geophysics text is always problematic: What should we teach students after they have had introductory courses in geology, math, and physics, but little else? Fundamentals of Geophysics is aimed specifically at these intermediate-level students, and the author's stated approach is to construct a text “using abundant diagrams, a simplified mathematical treatment, and equations in which the student can follow each derivation step-by-step.” Moreover, for Lowrie, the Earth is round, not flat—the “fundamentals of geophysics” here are the essential properties of our Earth the planet, rather than useful techniques for finding oil and minerals. Thus this book is comparable in both level and approach to C. M. R. Fowler's The Solid Earth (Cambridge University Press, 1990).

  12. Geophysical investigations in Jordan

    Science.gov (United States)

    Kovach, R.L.; Andreasen, G.E.; Gettings, M.E.; El-Kaysi, K.

    1990-01-01

    A number of geophysical investigations have been undertaken in the Hashemite Kingdom of Jordan to provide data for understanding the tectonic framework, the pattern of seismicity, earthquake hazards and geothermal resources of the country. Both the historical seismic record and the observed recent seismicity point to the dominance of the Dead Sea Rift as the main locus of seismic activity but significant branching trends and gaps in the seismicity pattern are also seen. A wide variety of focal plane solutions are observed emphasizing the complex pattern of fault activity in the vicinity of the rift zone. Geophysical investigations directed towards the geothermal assessment of the prominent thermal springs of Zerga Ma'in and Zara are not supportive of the presence of a crustal magmatic source. ?? 1990.

  13. Rapid Geophysical Surveyor

    International Nuclear Information System (INIS)

    Roybal, L.G.; Carpenter, G.S.; Josten, N.E.

    1993-01-01

    The Rapid Geophysical Surveyor (RGS) is a system designed to rapidly and economically collect closely-spaced geophysical data used for characterization of US Department of Energy waste sites. Geophysical surveys of waste sites are an important first step in the remediation and closure of these sites; especially older sites where historical records are inaccurate and survey benchmarks have changed because of refinements in coordinate controls and datum changes. Closely-spaced data are required to adequately differentiate pits, trenches, and soil vault rows whose edges may be only a few feet from each other. A prototype vehicle designed to collect magnetic field data was built at the Idaho National Engineering Laboratory (INEL) during the summer of 1992. The RGS was funded by the Buried Waste Integrated Demonstration program. This vehicle was demonstrated at the Subsurface Disposal Area (SDA) within the Radioactive Waste Management Complex at the INEL in September 1992. Magnetic data were collected over two areas in the SDA, with a total survey area of about 1.7 acres. Data were collected at a nominal density of 2 1/2 in. along survey lines spaced 1-ft apart. Over 350,000 data points were collected over a 6 day period corresponding to about 185 worker-days using conventional ground survey techniques

  14. Physical and chemical characteristics including total and geochemical forms of phosphorus in sediment from the top 30 centimeters of cores collected in October 2006 at 26 sites in Upper Klamath Lake, Oregon

    Science.gov (United States)

    Simon, Nancy S.; Ingle, Sarah N.

    2011-01-01

    μThis study of phosphorus (P) cycling in eutrophic Upper Klamath Lake (UKL), Oregon, was conducted by the U.S. Geological Survey in cooperation with the U.S. Bureau of Reclamation. Lakebed sediments from the upper 30 centimeters (cm) of cores collected from 26 sites were characterized. Cores were sampled at 0.5, 1.5, 2.5, 3.5, 4.5, 10, 15, 20, 25, and 30 cm. Prior to freezing, water content and sediment pH were determined. After being freeze-dried, all samples were separated into greater than 63-micron (μm) particle-size (coarse) and less than 63-μm particle-size (fine) fractions. In the surface samples (0.5 to 4.5 cm below the sediment water interface), approximately three-fourths of the particles were larger than 63-μm. The ratios of the coarse particle-size fraction (>63 μm) and the fine particle-size fraction (determination of total concentrations of aluminum (Al), calcium (Ca), carbon (C), iron (Fe), poorly crystalline Fe, nitrogen (N), P, and titanium (Ti). Total Fe concentrations were the largest in sediment from the northern portion of UKL, Howard Bay, and the southern portion of the lake. Concentrations of total Al, Ca, and Ti were largest in sediment from the northern, central, and southernmost portions of the lake and in sediment from Howard Bay. Concentrations of total C and N were largest in sediment from the embayments and in sediment from the northern arm and southern portion of the lake in the general region of Buck Island. Concentrations of total C were larger in the greater than 63-μm particle-size fraction than in the less than 63-μm particle-size fraction. Sediments were sequentially extracted to determine concentrations of inorganic forms of P, including loosely sorbed P, P associated with poorly crystalline Fe oxides, and P associated with mineral phases. The difference between the concentration of total P and sum of the concentrations of inorganic forms of P is referred to as residual P. Residual P was the largest fraction of P in all

  15. Image processing of airborne geophysical data: a potential exploration tool for atomic minerals

    International Nuclear Information System (INIS)

    Shanti Kumar, C.; Bhairam, C.L.; Kak, S.N.; Achar, K.K.

    1993-01-01

    Data sets obtained from airborne gamma-ray spectrometric (AGRS) and aeromagnetic (AM) surveys, after necessary correction, are usually presented as profiles or as contour maps for interpretation in mineral exploration and geological analysis. Currently, imaging of the geophysical data sets have been extensively used as they have many advantages in their usage compared to conventional techniques. For the application of image processing techniques to the AGRS and AM data, software programs were customized for converting the digital data compatible to the satellite image processing system (SIPS). The geophysical data has been imaged and rectified to a poly conic projection, using cubic convolution resampling technique. While imaging, the radioelemental concentration values are rescaled to 256 grey levels. Software for the statistical information of radioelements and printing of coloured paper image have also been developed. Some of the image processing techniques used include, generation of colour composite images for preparing radioelemental (eU,eTh, and K) images and radioelemental colour composite images (K,eTh, eU) enabling display of a combined radioelemental distribution. Aeromagnetic data on the other hand are displayed in grey tone, pseudo-colours, and shaded relief images. Many other image enhancement techniques used for improving the display for further interpretation comprise, band ratioing, band combinations, filtering, look up table manipulation, and other similar functions. Advanced image processing techniques such as the principal component analysis (PCA) for understanding the geochemical and geological phenomena and the hue saturation and intensity (HSI) transformation for integration of radioelemental data with its corresponding satellite images facilitated display of radioelemental images draped over the satellite image. Statistics of radioelement and inter-elemental relationship has been obtained. The paper deals with the methodology adopted in the

  16. Application of cluster analysis to geochemical compositional data for identifying ore-related geochemical anomalies

    Science.gov (United States)

    Zhou, Shuguang; Zhou, Kefa; Wang, Jinlin; Yang, Genfang; Wang, Shanshan

    2017-12-01

    Cluster analysis is a well-known technique that is used to analyze various types of data. In this study, cluster analysis is applied to geochemical data that describe 1444 stream sediment samples collected in northwestern Xinjiang with a sample spacing of approximately 2 km. Three algorithms (the hierarchical, k-means, and fuzzy c-means algorithms) and six data transformation methods (the z-score standardization, ZST; the logarithmic transformation, LT; the additive log-ratio transformation, ALT; the centered log-ratio transformation, CLT; the isometric log-ratio transformation, ILT; and no transformation, NT) are compared in terms of their effects on the cluster analysis of the geochemical compositional data. The study shows that, on the one hand, the ZST does not affect the results of column- or variable-based (R-type) cluster analysis, whereas the other methods, including the LT, the ALT, and the CLT, have substantial effects on the results. On the other hand, the results of the row- or observation-based (Q-type) cluster analysis obtained from the geochemical data after applying NT and the ZST are relatively poor. However, we derive some improved results from the geochemical data after applying the CLT, the ILT, the LT, and the ALT. Moreover, the k-means and fuzzy c-means clustering algorithms are more reliable than the hierarchical algorithm when they are used to cluster the geochemical data. We apply cluster analysis to the geochemical data to explore for Au deposits within the study area, and we obtain a good correlation between the results retrieved by combining the CLT or the ILT with the k-means or fuzzy c-means algorithms and the potential zones of Au mineralization. Therefore, we suggest that the combination of the CLT or the ILT with the k-means or fuzzy c-means algorithms is an effective tool to identify potential zones of mineralization from geochemical data.

  17. The effect of scale on the interpretation of geochemical anomalies

    Science.gov (United States)

    Theobald, P.K.; Eppinger, R.G.; Turner, R.L.; Shiquan, S.

    1991-01-01

    The purpose of geochemical surveys changes with scale. Regional surveys identify areas where mineral deposits are most likely to occur, whereas intermediate surveys identify and prioritize specific targets. At detailed scales specific deposit models may be applied and deposits delineated. The interpretation of regional geochemical surveys must take into account scale-dependent difference in the nature and objectives of this type of survey. Overinterpretation of regional data should be resisted, as should recommendations to restrict intermediate or detailed follow-up surveys to the search for specific deposit types or to a too limited suite of elements. Regional surveys identify metallogenic provinces within which a variety of deposit types and metals are most likely to be found. At intermediate scale, these regional provinces often dissipate into discrete clusters of anomalous areas. At detailed scale, individual anomalous areas reflect local conditions of mineralization and may seem unrelated to each other. Four examples from arid environments illustrate the dramatic change in patterns of anomalies between regional and more detailed surveys. On the Arabian Shield, a broad regional anomaly reflects the distribution of highly differentiated anorogenic granites. A particularly prominent part of the regional anomaly includes, in addition to the usual elements related to the granites, the assemblage of Mo, W and Sn. Initial interpretation suggested potential for granite-related, stockwork Mo deposits. Detailed work identified three separate sources for the anomaly: a metal-rich granite, a silicified and stockwork-veined area with scheelite and molybdenite, and scheelite/powellite concentrations in skarn deposits adjacent to a ring-dike complex. Regional geochemical, geophysical and remote-sensing data in the Sonoran Desert, Mexico, define a series of linear features interpreted to reflect fundamental, northeast-trending fractures in the crust that served as the prime

  18. HMF-Geophysics - An Update

    Science.gov (United States)

    Crook, N.; Knight, R.; Robinson, D.

    2007-12-01

    There is growing recognition of the challenges we face, in many parts of the world, in finding and maintaining clean sources of water for human consumption and agricultural use, while balancing the needs of the natural world. Advancements in hydrologic sciences are needed in order to develop an improved understanding of the controls on the quantity, movement, and quality of water, thus enhancing our ability to better protect and manage our water resources. Geophysical methods can play a central role in these investigations. CUAHSI (Consortium of Universities for the Advancement of Hydrologic Sciences) is developing, with the support of the National Science Foundation, a Hydrologic Measurement Facility (HMF), which contains a Geophysics module, referred to as HMF-Geophysics. The Geophysics module will support and advance the use of geophysics for hydrologic applications. Currently in second year of a 3 year pilot study, the main aim of HMF-Geophysics is to develop the infrastructure necessary to provide geophysical techniques and the expertise to apply them correctly for the hydrological community. The current working model consists of a central HMF-Geophysics facility and a number of volunteer nodes. The latter consists of individuals at universities who have volunteered to be part of HMF-Geophysics by using their equipment, and/or software, and expertise, in research partnerships with hydrologists. In response to an inquiry the central facility takes on the evaluation of the potential of geophysics to the area of research/watershed. The central facility can then undertake a feasibility study to determine how/if geophysical methods could be of use, and to evaluate the "value-added" by geophysics to the science. Once it is clear that the geophysics can contribute in a significant way to addressing the science questions the central facility works with the hydrologist to set up the next step. Our assumption is that at this point, the hydrologist (perhaps with a

  19. Geochemical Survey of Pernambuco

    International Nuclear Information System (INIS)

    Horowitz, A.; Duarte, P.J.; Almeida, M.G. de; Medeiros, M.O.

    1988-01-01

    The area studied i this work is located in a triangle formed by the Sibiro and Boca da Mata Sugar-Mills and Serinhaem country. In the Cabo Formation the search determinated conglomerates, arcos and clays. Although the highest geochemical activity have been done in the decomposed crystalin, and the values from Cabo Formation don't be encourager, this formation has lithology compatible with uranium mineralization. The Cabo Formation's sediments presents lithologic variations very expressives, with conglomerates, arcoses and clay silts, which determinate the choise of the area. This area presented favorable to uranium prospecting and to others elements interesting to ragional geochemistry. The atomic absorption analysis, fluorimetry and spectrometry were done for the following elements: Zn, V, Ti, Ni, Pb, Mn, Ga, Cu, Co, Bi, Ag, B, Mo, and U. (C.D.G.) [pt

  20. Geophysical fluid dynamics

    CERN Document Server

    Pedlosky, Joseph

    1982-01-01

    The content of this book is based, largely, on the core curriculum in geophys­ ical fluid dynamics which land my colleagues in the Department of Geophysical Sciences at The University of Chicago have taught for the past decade. Our purpose in developing a core curriculum was to provide to advanced undergraduates and entering graduate students a coherent and systematic introduction to the theory of geophysical fluid dynamics. The curriculum and the outline of this book were devised to form a sequence of courses of roughly one and a half academic years (five academic quarters) in length. The goal of the sequence is to help the student rapidly advance to the point where independent study and research are practical expectations. It quickly became apparent that several topics (e. g. , some aspects of potential theory) usually thought of as forming the foundations of a fluid-dynamics curriculum were merely classical rather than essential and could be, however sadly, dispensed with for our purposes. At the same tim...

  1. Geophysical fluid dynamics

    CERN Document Server

    Pedlosky, Joseph

    1979-01-01

    The content of this book is based, largely, on the core curriculum in geophys­ ical fluid dynamics which I and my colleagues in the Department of Geophysical Sciences at The University of Chicago have taught for the past decade. Our purpose in developing a core curriculum was to provide to advanced undergraduates and entering graduate students a coherent and systematic introduction to the theory of geophysical fluid dynamics. The curriculum and the outline of this book were devised to form a sequence of courses of roughly one and a half academic years (five academic quarters) in length. The goal of the sequence is to help the student rapidly advance to the point where independent study and research are practical expectations. It quickly became apparent that several topics (e. g. , some aspects of potential theory) usually thought of as forming the foundations of a fluid-dynamics curriculum were merely classical rather than essential and could be, however sadly, dispensed with for our purposes. At the same ti...

  2. The IUGS/IAGC Task Group on Global Geochemical Baselines

    Science.gov (United States)

    Smith, David B.; Wang, Xueqiu; Reeder, Shaun; Demetriades, Alecos

    2012-01-01

    The Task Group on Global Geochemical Baselines, operating under the auspices of both the International Union of Geological Sciences (IUGS) and the International Association of Geochemistry (IAGC), has the long-term goal of establishing a global geochemical database to document the concentration and distribution of chemical elements in the Earth’s surface or near-surface environment. The database and accompanying element distribution maps represent a geochemical baseline against which future human-induced or natural changes to the chemistry of the land surface may be recognized and quantified. In order to accomplish this long-term goal, the activities of the Task Group include: (1) developing partnerships with countries conducting broad-scale geochemical mapping studies; (2) providing consultation and training in the form of workshops and short courses; (3) organizing periodic international symposia to foster communication among the geochemical mapping community; (4) developing criteria for certifying those projects whose data are acceptable in a global geochemical database; (5) acting as a repository for data collected by those projects meeting the criteria for standardization; (6) preparing complete metadata for the certified projects; and (7) preparing, ultimately, a global geochemical database. This paper summarizes the history and accomplishments of the Task Group since its first predecessor project was established in 1988.

  3. Geophysical data fusion for subsurface imaging

    International Nuclear Information System (INIS)

    Hoekstra, P.; Vandergraft, J.; Blohm, M.; Porter, D.

    1993-08-01

    A geophysical data fusion methodology is under development to combine data from complementary geophysical sensors and incorporate geophysical understanding to obtain three dimensional images of the subsurface. The research reported here is the first phase of a three phase project. The project focuses on the characterization of thin clay lenses (aquitards) in a highly stratified sand and clay coastal geology to depths of up to 300 feet. The sensor suite used in this work includes time-domain electromagnetic induction (TDEM) and near surface seismic techniques. During this first phase of the project, enhancements to the acquisition and processing of TDEM data were studied, by use of simulated data, to assess improvements for the detection of thin clay layers. Secondly, studies were made of the use of compressional wave and shear wave seismic reflection data by using state-of-the-art high frequency vibrator technology. Finally, a newly developed processing technique, called ''data fusion,'' was implemented to process the geophysical data, and to incorporate a mathematical model of the subsurface strata. Examples are given of the results when applied to real seismic data collected at Hanford, WA, and for simulated data based on the geology of the Savannah River Site

  4. 75 FR 16830 - Geological and Geophysical Exploration (G&G) on the Mid- and South Atlantic Outer Continental...

    Science.gov (United States)

    2010-04-02

    ... DEPARTMENT OF THE INTERIOR Minerals Management Service Geological and Geophysical Exploration (G&G..., geological and geochemical sampling, and remote sensing. These activities could support siting needs for... Continental Shelf (see http://www.mms.gov/ld/PDFs/GreenBook-LeasingDocument.pdf ) and MMS's Geological and...

  5. Developments in geophysical exploration methods

    CERN Document Server

    1982-01-01

    One of the themes in current geophysical development is the bringing together of the results of observations made on the surface and those made in the subsurface. Several benefits result from this association. The detailed geological knowledge obtained in the subsurface can be extrapolated for short distances with more confidence when the geologi­ cal detail has been related to well-integrated subsurface and surface geophysical data. This is of value when assessing the characteristics of a partially developed petroleum reservoir. Interpretation of geophysical data is generally improved by the experience of seeing the surface and subsurface geophysical expression of a known geological configuration. On the theoretical side, the understanding of the geophysical processes themselves is furthered by the study of the phenomena in depth. As an example, the study of the progress of seismic wave trains downwards and upwards within the earth has proved most instructive. This set of original papers deals with some of ...

  6. A >100 Ma Mantle Geochemical Record: Retiring Mantle Plumes may be Premature

    Science.gov (United States)

    Konter, J. G.; Hanan, B. B.; Blichert-Toft, J.; Koppers, A. A.; Plank, T.; Staudigel, H.

    2006-12-01

    Hotspot volcanism has long been attributed to mantle plumes, but in recent years suggestions have been made that plate tectonic processes, such as extension, can account for all hotspot tracks. This explanation involves a profoundly less dynamic lower mantle, which justifies a critical evaluation before the plume model is dismissed. Such an evaluation has to involve a wide range of geochemical, geological, and geophysical techniques, broadly investigating the products of volcanism as well as the underlying lithosphere and mantle. We argue here that the combined geological record and geochemistry of intraplate volcanoes holds some important clues that help us decide between models of plume-like upwelling versus passive upwelling with lithospheric extension. The best of these integrated datasets can be obtained from the long seamount chains in the Pacific Ocean. A new combined dataset of trace element and isotopic compositions, along with modern 40Ar/39Ar ages from seamounts in the Gilbert Ridge, Tokelau chain, and West Pacific Seamount Province (WPSP) provides a record of current to Cretaceous volcanism in the South Pacific. We have reconstructed the eruptive locations of the seamounts using a range of absolute plate motion models, including some models with hotspot motion and others that use the Indo-Atlantic hotspot reference frame. Our results show that the backtracked locations consistently form clusters (300km radius) around the active ends of the Macdonald, Rurutu and Rarotonga hotspot chains, while closely matching their distinct C-HIMU and C-EM1 signatures. The oldest WPSP seamounts (older than 100 Ma) form the only exception and backtrack, with larger uncertainty, to north of Rarotonga. Therefore, the mantle currently underlying the Cook-Austral islands has produced volcanoes in three geochemically distinct areas for at least 100 m.y. Furthermore, we find the shortest mantle residence time, 0.6 Ga, for a source of mixed recycled DMM and an EM1-like

  7. Geochemical indicators of gold ore fields

    International Nuclear Information System (INIS)

    Shcherbakov, Yu.G.

    1995-01-01

    The principles of selection of indicators for genetic reconstructions and prognostic valuations of gold mineralization of diverse morphological and geochemical types have been substantiated. The neutron-activation analysis with radiochemical separation and detection limit of 1-10 -8 %, instrumental neutron-activation analysis and atomic-absorption analysis are the main methods of determination of gold low contents in the rocks, as well as diverse elements, including transition, rare earth elements and tellurium, in gold. 50 refs.; 1 fig.; 3 tabs

  8. Statistical interpretation of geochemical data

    International Nuclear Information System (INIS)

    Carambula, M.

    1990-01-01

    Statistical results have been obtained from a geochemical research from the following four aerial photographies Zapican, Carape, Las Canias, Alferez. They have been studied 3020 samples in total, to 22 chemical elements using plasma emission spectrometry methods.

  9. Geophysical monitoring in a hydrocarbon reservoir

    Science.gov (United States)

    Caffagni, Enrico; Bokelmann, Goetz

    2016-04-01

    Extraction of hydrocarbons from reservoirs demands ever-increasing technological effort, and there is need for geophysical monitoring to better understand phenomena occurring within the reservoir. Significant deformation processes happen when man-made stimulation is performed, in combination with effects deriving from the existing natural conditions such as stress regime in situ or pre-existing fracturing. Keeping track of such changes in the reservoir is important, on one hand for improving recovery of hydrocarbons, and on the other hand to assure a safe and proper mode of operation. Monitoring becomes particularly important when hydraulic-fracturing (HF) is used, especially in the form of the much-discussed "fracking". HF is a sophisticated technique that is widely applied in low-porosity geological formations to enhance the production of natural hydrocarbons. In principle, similar HF techniques have been applied in Europe for a long time in conventional reservoirs, and they will probably be intensified in the near future; this suggests an increasing demand in technological development, also for updating and adapting the existing monitoring techniques in applied geophysics. We review currently available geophysical techniques for reservoir monitoring, which appear in the different fields of analysis in reservoirs. First, the properties of the hydrocarbon reservoir are identified; here we consider geophysical monitoring exclusively. The second step is to define the quantities that can be monitored, associated to the properties. We then describe the geophysical monitoring techniques including the oldest ones, namely those in practical usage from 40-50 years ago, and the most recent developments in technology, within distinct groups, according to the application field of analysis in reservoir. This work is performed as part of the FracRisk consortium (www.fracrisk.eu); this project, funded by the Horizon2020 research programme, aims at helping minimize the

  10. Alterations in geochemical associations in artificially disturbed deep-sea sediments

    Digital Repository Service at National Institute of Oceanography (India)

    Nath, B.N.; Parthiban, G.; Banaulikar, S.; Sarkar, S.

    Alterations in Geochemical Associations in Artificially Disturbed Deep-Sea Sediments B. NAGENDER NATH, G. PARTHIBAN, AND S. BANAULIKAR National Institute of Oceanography, Dona Paula, Goa, India SUBHADEEP SARKAR Department of Geology and Geophysics, Indian... the lithogenic component by transporting it from other locations within the Basin during commercial mining operations. Keywords manganese nodule mining, artificial benthic disturbance experiment, environmental impact assessment, metals Trace metals in marine...

  11. Geochemical reanalysis of historical U.S. Geological Survey sediment samples from the Tonsina area, Valdez Quadrangle, Alaska

    Science.gov (United States)

    Werdon, Melanie B.; Granitto, Matthew; Azain, Jaime S.

    2015-01-01

    The State of Alaska’s Strategic and Critical Minerals (SCM) Assessment project, a State-funded Capital Improvement Project (CIP), is designed to evaluate Alaska’s statewide potential for SCM resources. The SCM Assessment is being implemented by the Alaska Division of Geological & Geophysical Surveys (DGGS), and involves obtaining new airborne-geophysical, geological, and geochemical data. As part of the SCM Assessment, thousands of historical geochemical samples from DGGS, U.S. Geological Survey (USGS), and U.S. Bureau of Mines archives are being reanalyzed by DGGS using modern, quantitative, geochemical-analytical methods. The objective is to update the statewide geochemical database to more clearly identify areas in Alaska with SCM potential. The USGS is also undertaking SCM-related geologic studies in Alaska through the federally funded Alaska Critical Minerals cooperative project. DGGS and USGS share the goal of evaluating Alaska’s strategic and critical minerals potential and together created a Letter of Agreement (signed December 2012) and a supplementary Technical Assistance Agreement (#14CMTAA143458) to facilitate the two agencies’ cooperative work. Under these agreements, DGGS contracted the USGS in Denver to reanalyze historical USGS sediment samples from Alaska. For this report, DGGS funded reanalysis of 128 historical USGS sediment samples from the statewide Alaska Geochemical Database Version 2.0 (AGDB2; Granitto and others, 2013). Samples were chosen from the Tonsina area in the Chugach Mountains, Valdez quadrangle, Alaska (fig. 1). The USGS was responsible for sample retrieval from the National Geochemical Sample Archive (NGSA) in Denver, Colorado through the final quality assurance/quality control (QA/QC) of the geochemical analyses obtained through the USGS contract lab. The new geochemical data are published in this report as a coauthored DGGS report, and will be incorporated into the statewide geochemical databases of both agencies

  12. Geochemical reanalysis of historical U.S. Geological Survey sediment samples from the Zane Hills, Hughes and Shungnak quadrangles, Alaska

    Science.gov (United States)

    Werdon, Melanie B.; Granitto, Matthew; Azain, Jaime S.

    2015-01-01

    The State of Alaska’s Strategic and Critical Minerals (SCM) Assessment project, a State-funded Capital Improvement Project (CIP), is designed to evaluate Alaska’s statewide potential for SCM resources. The SCM Assessment is being implemented by the Alaska Division of Geological & Geophysical Surveys (DGGS), and involves obtaining new airborne-geophysical, geological, and geochemical data. As part of the SCM Assessment, thousands of historical geochemical samples from DGGS, U.S. Geological Survey (USGS), and U.S. Bureau of Mines archives are being reanalyzed by DGGS using modern, quantitative, geochemical-analytical methods. The objective is to update the statewide geochemical database to more clearly identify areas in Alaska with SCM potential.The USGS is also undertaking SCM-related geologic studies in Alaska through the federally funded Alaska Critical Minerals cooperative project. DGGS and USGS share the goal of evaluating Alaska’s strategic and critical minerals potential and together created a Letter of Agreement (signed December 2012) and a supplementary Technical Assistance Agreement (#14CMTAA143458) to facilitate the two agencies’ cooperative work. Under these agreements, DGGS contracted the USGS in Denver to reanalyze historical USGS sediment samples from Alaska.For this report, DGGS funded reanalysis of 105 historical USGS sediment samples from the statewide Alaska Geochemical Database Version 2.0 (AGDB2; Granitto and others, 2013). Samples were chosen from the Zane Hills area in the Hughes and Shungnak quadrangles, Alaska (fig. 1). The USGS was responsible for sample retrieval from the National Geochemical Sample Archive (NGSA) in Denver, Colorado through the final quality assurance/quality control (QA/QC) of the geochemical analyses obtained through the USGS contract lab. The new geochemical data are published in this report as a coauthored DGGS report, and will be incorporated into the statewide geochemical databases of both agencies.

  13. Predictive geochemical mapping using environmental correlation

    International Nuclear Information System (INIS)

    Wilford, John; Caritat, Patrice de; Bui, Elisabeth

    2016-01-01

    The distribution of chemical elements at and near the Earth's surface, the so-called critical zone, is complex and reflects the geochemistry and mineralogy of the original substrate modified by environmental factors that include physical, chemical and biological processes over time. Geochemical data typically is illustrated in the form of plan view maps or vertical cross-sections, where the composition of regolith, soil, bedrock or any other material is represented. These are primarily point observations that frequently are interpolated to produce rasters of element distributions. Here we propose the application of environmental or covariate regression modelling to predict and better understand the controls on major and trace element geochemistry within the regolith. Available environmental covariate datasets (raster or vector) representing factors influencing regolith or soil composition are intersected with the geochemical point data in a spatial statistical correlation model to develop a system of multiple linear correlations. The spatial resolution of the environmental covariates, which typically is much finer (e.g. ∼90 m pixel) than that of geochemical surveys (e.g. 1 sample per 10-10,000 km 2 ), carries over to the predictions. Therefore the derived predictive models of element concentrations take the form of continuous geochemical landscape representations that are potentially much more informative than geostatistical interpolations. Environmental correlation is applied to the Sir Samuel 1:250,000 scale map sheet in Western Australia to produce distribution models of individual elements describing the geochemical composition of the regolith and exposed bedrock. As an example we model the distribution of two elements – chromium and sodium. We show that the environmental correlation approach generates high resolution predictive maps that are statistically more accurate and effective than ordinary kriging and inverse distance weighting interpolation

  14. Geochemical exploration for uranium

    International Nuclear Information System (INIS)

    Rose, A.W.

    1977-01-01

    The processes and types of dispersion that produce anomalies in stream water, stream sediment, and ground water, and the factors that must be considered in planning and interpreting geochemical surveys are reviewed. Examples of surveys near known deposits show the types of results to be expected. Background values depend mainly on the content of U in rocks of the drainage area. In igneous rocks, U tends to increase with potassium from ultramafic rocks (0.01 ppM) to granitic rocks (1 to 5 ppM). Some alkalic rocks have unusually high contents of U (15 to 100 ppM). Uranium-rich provinces marked by igneous rocks unusually rich in U are recognized in several areas and appear to have a deep crustal or mantle origin. In western U.S., many tertiary tuffaceous rocks have a high U content. Sandstones, limestones, and many shales approximate the crustal abundance at 0.5 to 4 ppM, but black shales, phosphates, and some organic materials are notably enriched in U. Uranium is very soluble in most oxidizing waters at the earth's surface, but is precipitated by reducing agents (organic matter, H 2 S) and adsorbed by organic material and some Fe oxides. In most surface and ground waters, U correlates approximately with the total dissolved solids, conductivity, and bicarbonate concentration of the water, and with the U content of rocks it comes into contact with. Most surveys of stream water near known districts show distinct anomalies extending a few km to tens of km downstream. A complication with water is the large variability with time, up to x 50, as a result of changes in the ratio of ground water to direct runoff, and changes in rate of oxidation and leaching. Collection and analysis of water samples also pose some difficulties

  15. The geology and geophysics of the Oslo rift

    Science.gov (United States)

    Ruder, M. E.

    1981-01-01

    The regional geology and geophysical characteristics of the Oslo graben are reviewed. The graben is part of a Permian age failed continental rift. Alkali olivine, tholefitic, and monzonitic intrusives as well as basaltic lavas outline the extent of the graben. Geophysical evidence indicates that rifting activity covered a much greater area in Skagerrak Sea as well as the Paleozoic time, possibly including the northern Skagerrak Sea as well as the Oslo graben itself. Much of the surficial geologic characteristics in the southern part of the rift have since been eroded or covered by sedimentation. Geophysical data reveal a gravity maximum along the strike of the Oslo graben, local emplacements of magnetic material throughout the Skagerrak and the graben, and a slight mantle upward beneath the rift zone. Petrologic and geophysical maps which depict regional structure are included in the text. An extensive bibliography of pertinent literature published in English between 1960 and 1980 is also provided.

  16. Collected radiochemical and geochemical procedures

    Energy Technology Data Exchange (ETDEWEB)

    Kleinberg, J [comp.

    1990-05-01

    This revision of LA-1721, 4th Ed., Collected Radiochemical Procedures, reflects the activities of two groups in the Isotope and Nuclear Chemistry Division of the Los Alamos National Laboratory: INC-11, Nuclear and radiochemistry; and INC-7, Isotope Geochemistry. The procedures fall into five categories: I. Separation of Radionuclides from Uranium, Fission-Product Solutions, and Nuclear Debris; II. Separation of Products from Irradiated Targets; III. Preparation of Samples for Mass Spectrometric Analysis; IV. Dissolution Procedures; and V. Geochemical Procedures. With one exception, the first category of procedures is ordered by the positions of the elements in the Periodic Table, with separate parts on the Representative Elements (the A groups); the d-Transition Elements (the B groups and the Transition Triads); and the Lanthanides (Rare Earths) and Actinides (the 4f- and 5f-Transition Elements). The members of Group IIIB-- scandium, yttrium, and lanthanum--are included with the lanthanides, elements they resemble closely in chemistry and with which they occur in nature. The procedures dealing with the isolation of products from irradiated targets are arranged by target element.

  17. Methodology of Detailed Geophysical Examination of the Areas of World Recognized Religious and Cultural Artifacts

    Science.gov (United States)

    Eppelbaum, Lev

    2010-05-01

    the low altitudes (3-5 meters) will help geophysical cover all the studied area with a regular observation step (Eppelbaum, 2008). At the final step all these measurements (including results of the previous works) could be compiled to 4D models of different geophysical parameters (Eppelbaum and Ben-Avraham, 2002; Eppelbaum et al., 2010). Analysis of temperature field in the boreholes drilled in the vicinity of the studied site will permit to estimate the temperature (e.g., Eppelbaum et al., 2006c) in the historical period when this artifact was constructed and, correspondingly, utilize this characteristic for investigation of mechanical and other properties of the ancient building material. Studying of temporal variations of magnetic (e.g., Finkelstein and Eppelbaum) and VLF fields can be also used for determination of nature of some buried ancient remains. The geophysical investigations must be combined with geochemical, paleostructural, paleobiogeographical, paleomorphological and other methods (Eppelbaum et al., 2010). Application of informational parameters (Khesin et al., 1996; Eppelbaum et al., 2003b) will permit to present all available data by the use of integral convolution units. REFERENCES Eppelbaum, L.V., 1999. Quantitative interpretation of resistivity anomalies using advanced methods developed in magnetic prospecting. Trans. of the XXIV General Assembly of the Europ. Geoph. Soc., Strasburg 1 (1), p.166. Eppelbaum, L.V., 2000. Applicability of geophysical methods for localization of archaeological targets: An introduction. Geoinformatics, 11, No.1, 19-28. Eppelbaum, L.V., 2005. Multilevel observations of magnetic field at archaeological sites as additional interpreting tool. Proceed. of the 6th Conference of Archaeological Prospection, Roma, Italy, 4 pp. Eppelbaum, L.V., 2008. Remote operated vehicle geophysical survey using magnetic and VLF methods: proposed schemes for data processing and interpretation. Proceed. of the Symp. on the Application of

  18. GEOPHYSICAL PROPERTIES OF SOILS

    KAUST Repository

    Santamarina, Carlos

    2016-12-01

    Low energy perturbations used in geophysical methods provide insightful information about constant-fabric soil properties and their spatial variability. There are causal links between soil type, index properties, elastic wave velocity, electromagnetic wave parameters and thermal properties. Soil type relates to the stress-dependent S-wave velocity, thermal and electrical conductivity and permittivity. The small strain stiffness reflects the state of stress, the extent of diagenetic cementation and/or freezing. Pore fluid chemistry, fluid phase and changes in either fluid chemistry or phase manifest through electromagnetic measurements. The volumetric water content measured with electromagnetic techniques is the best predictor of porosity if the water saturation is 100%. Changes in water saturation alter the P-wave velocity when Srà100%, the S-wave velocity at intermediate saturations, and the thermal conductivity when the saturation is low Srà0%. Finally, tabulated values suffice to estimate heat capacity and latent heat for engineering design, however thermal conductivity requires measurements under proper field conditions.

  19. A review of nuclear geophysics

    International Nuclear Information System (INIS)

    Clayton, C.G.; Schweitzer, J.S.

    1992-01-01

    This paper summarizes the development of nuclear geophysics in scientific and technological content and in range from its beginnings early in this century to the present day. We note that the early work in nuclear geophysics was originally referred to under the umbrella of open-quotes isotope applicationsclose quotes and the origin of the term open-quotes nuclear geophysicsclose quotes (which is seen to clarify and to focus work in this area) is exposed in this paper. The current expansion of nuclear geophysics front its original concern with oil well logging is an important trend because much of the underlying science, technology, and instrumentation is common ground. A review of nuclear geophysics would be a barren document without reference to long-term and, in some cases, short-term commercial and economic as well as to technological considerations, since these factors are the principal motivation for further development

  20. Monitoring active volcanoes: The geochemical approach

    Directory of Open Access Journals (Sweden)

    Takeshi Ohba

    2011-06-01

    Full Text Available

    The geochemical surveillance of an active volcano aims to recognize possible signals that are related to changes in volcanic activity. Indeed, as a consequence of the magma rising inside the volcanic "plumbing system" and/or the refilling with new batches of magma, the dissolved volatiles in the magma are progressively released as a function of their relative solubilities. When approaching the surface, these fluids that are discharged during magma degassing can interact with shallow aquifers and/or can be released along the main volcano-tectonic structures. Under these conditions, the following main degassing processes represent strategic sites to be monitored.

    The main purpose of this special volume is to collect papers that cover a wide range of topics in volcanic fluid geochemistry, which include geochemical characterization and geochemical monitoring of active volcanoes using different techniques and at different sites. Moreover, part of this volume has been dedicated to the new geochemistry tools.

  1. COTHERM: Geophysical Modeling of High Enthalpy Geothermal Systems

    Science.gov (United States)

    Grab, Melchior; Maurer, Hansruedi; Greenhalgh, Stewart

    2014-05-01

    In recent years geothermal heating and electricity generation have become an attractive alternative energy resource, especially natural high enthalpy geothermal systems such as in Iceland. However, the financial risk of installing and operating geothermal power plants is still high and more needs to be known about the geothermal processes and state of the reservoir in the subsurface. A powerful tool for probing the underground system structure is provided by geophysical techniques, which are able to detect flow paths and fracture systems without drilling. It has been amply demonstrated that small-scale features can be well imaged at shallow depths, but only gross structures can be delineated for depths of several kilometers, where most high enthalpy systems are located. Therefore a major goal of our study is to improve geophysical mapping strategies by multi-method geophysical simulations and synthetic data inversions, to better resolve structures at greater depth, characterize the reservoir and monitor any changes within it. The investigation forms part of project COTHERM - COmbined hydrological, geochemical and geophysical modeling of geoTHERMal systems - in which a holistic and synergistic approach is being adopted to achieve multidisciplinary cooperation and mutual benefit. The geophysical simulations are being performed in combination with hydrothermal fluid flow modeling and chemical fluid rock interaction modeling, to provide realistic constraints on lithology, pressure, temperature and fluid conditions of the subsurface. Two sites in Iceland have been selected for the study, Krafla and Reykjanes. As a starting point for the geophysical modeling, we seek to establish petrophysical relations, connecting rock properties and reservoir conditions with geophysical parameters such as seismic wave speed, attenuation, electrical conductivity and magnetic susceptibility with a main focus on seismic properties. Therefore, we follow a comprehensive approach involving

  2. Geophysical Exploration. New site exploration method

    Energy Technology Data Exchange (ETDEWEB)

    Imai, Tsuneo; Otomo, Hideo; Sakayama, Toshihiko

    1988-07-25

    Geophysical exploration is used for geologic survey to serve purposes in civil engineering. New methods are being developed inside and outside Japan and are used to serve various purposes. This paper discusses recently developed techniques based on the measurement of seismic waves and electric potential. It also explains seismic tomography, radar tomography, and resistivity tomography which are included in the category of geotomography. At present, effort is being made to apply geophysical exploration technology to problems which were considered to be unsuitable for conventional exploration techniques. When such effort proceeds successfully, it is necessary to develop technology for presenting results quickly and exploration equipment which can work in various conditions. (10 figs, 15 refs)

  3. Geophysical investigations at ORNL solid waste storage area 3

    International Nuclear Information System (INIS)

    Rothschild, E.R.; Switek, J.; Llopis, J.L.; Farmer, C.D.

    1985-07-01

    Geophysical investigations at ORNL solid waste storage area 3 have been carried out. The investigations included very-low-frequency-electromagnetic resistivity (VLF-EM), electrical resistivity, and seismic refraction surveys. The surveys resulted in the measurement of basic geophysical rock properties, as well as information on the depth of weathering and the configuration of the bedrock surface beneath the study area. Survey results also indicate that a number of geophysical anomalies occur in the shallow subsurface at the site. In particular, a linear feature running across the geologic strike in the western half of the waste disposal facility has been identified. This feature may conduct water in the subsurface. The geophysical investigations are part of an ongoing effort to characterize the site's hydrogeology, and the data presented will be valuable in directing future drilling and investigations at the site. 10 refs., 6 figs

  4. Geophysical Anomalies and Earthquake Prediction

    Science.gov (United States)

    Jackson, D. D.

    2008-12-01

    Finding anomalies is easy. Predicting earthquakes convincingly from such anomalies is far from easy. Why? Why have so many beautiful geophysical abnormalities not led to successful prediction strategies? What is earthquake prediction? By my definition it is convincing information that an earthquake of specified size is temporarily much more likely than usual in a specific region for a specified time interval. We know a lot about normal earthquake behavior, including locations where earthquake rates are higher than elsewhere, with estimable rates and size distributions. We know that earthquakes have power law size distributions over large areas, that they cluster in time and space, and that aftershocks follow with power-law dependence on time. These relationships justify prudent protective measures and scientific investigation. Earthquake prediction would justify exceptional temporary measures well beyond those normal prudent actions. Convincing earthquake prediction would result from methods that have demonstrated many successes with few false alarms. Predicting earthquakes convincingly is difficult for several profound reasons. First, earthquakes start in tiny volumes at inaccessible depth. The power law size dependence means that tiny unobservable ones are frequent almost everywhere and occasionally grow to larger size. Thus prediction of important earthquakes is not about nucleation, but about identifying the conditions for growth. Second, earthquakes are complex. They derive their energy from stress, which is perniciously hard to estimate or model because it is nearly singular at the margins of cracks and faults. Physical properties vary from place to place, so the preparatory processes certainly vary as well. Thus establishing the needed track record for validation is very difficult, especially for large events with immense interval times in any one location. Third, the anomalies are generally complex as well. Electromagnetic anomalies in particular require

  5. Site characterization at the Rabbit Valley Geophysical Performance Evaluation Range

    International Nuclear Information System (INIS)

    Koppenjan, S.; Martinez, M.

    1994-01-01

    The United States Department of Energy (US DOE) is developing a Geophysical Performance Evaluation Range (GPER) at Rabbit Valley located 30 miles west of Grand Junction, Colorado. The purpose of the range is to provide a test area for geophysical instruments and survey procedures. Assessment of equipment accuracy and resolution is accomplished through the use of static and dynamic physical models. These models include targets with fixed configurations and targets that can be re-configured to simulate specific specifications. Initial testing (1991) combined with the current tests at the Rabbit Valley GPER will establish baseline data and will provide performance criteria for the development of geophysical technologies and techniques. The US DOE's Special Technologies Laboratory (STL) staff has conducted a Ground Penetrating Radar (GPR) survey of the site with its stepped FM-CW GPR. Additionally, STL contracted several other geophysical tests. These include an airborne GPR survey incorporating a ''chirped'' FM-CW GPR system and a magnetic survey with a surfaced-towed magnetometer array unit Ground-based and aerial video and still frame pictures were also acquired. STL compiled and analyzed all of the geophysical maps and created a site characterization database. This paper discusses the results of the multi-sensor geophysical studies performed at Rabbit Valley and the future plans for the site

  6. Notes on the history of geophysics in the Ottoman Empire

    Science.gov (United States)

    Ozcep, F.; Ozcep, T.

    2014-09-01

    In Anatolia, the history of geophysical sciences may go back to antiquity (600 BC), namely the period when Thales lived in Magnesia (Asia Minor). In the modern sense, geophysics started with geomagnetic works in the 1600s. The period between 1600 and 1800 includes the measurement of magnetic declination, inclination and magnetic field strength. Before these years, there is a little information, such as how to use a compass, in the Kitab-i Bahriye (the Book of Navigation) of Piri Reis, who is one of the most important mariners of the Ottoman Empire. However, this may not mean that magnetic declination was generally understood. The first scientific book relating to geophysics is the book Fuyuzat-i Miknatissiye that was translated by Ibrahim Müteferrika and printed in 1731. The subject of this book is earth's magnetism. There is also information concerning geophysics in the book Cihannuma (Universal Geography) that was written by Katip Celebi and in the book Marifetname written by Ibrahim Hakki Erzurumlu, but these books are only partly geophysical books. In Istanbul the year 1868 is one of the most important for geophysical sciences because an observatory called Rasathane-i Amire was installed in the Pera region of this city. At this observatory the first systematic geophysical observations such as meteorological, seismological and even gravimetrical were made. There have been meteorological records in Anatolia since 1839. These are records of atmospheric temperature, pressure and humidity. In the Ottoman Empire, the science of geophysics is considered as one of the natural sciences along with astronomy, mineralogy, geology, etc., and these sciences are included as a part of physics and chemistry.

  7. Development of Geophysical Ideas and Institutions in Ottoman Empire

    Science.gov (United States)

    Ozcep, Ferhat; Ozcep, Tazegul

    2015-04-01

    In Anatolia, the history of geophysical sciences may go back to antiquity (600 BC), namely the period when Thales lived in Magnesia (Asia Minor). In the modern sense, geophysics started with geomagnetic works in the 1600s. The period between 1600 and 1800 includes the measurement of magnetic declination, inclination and magnetic field strength. Before these years, there is a little information, such as how to use a compass, in the Kitab-i Bahriye (the Book of Navigation) of Piri Reis, who is one of the most important mariners of the Ottoman Empire. However, this may not mean that magnetic declination was generally understood. The first scientific book relating to geophysics is the book Fuyuzat-i Miknatissiye that was translated by Ibrahim Müteferrika and printed in 1731. The subject of this book is earth's magnetism. There is also information concerning geophysics in the book Cihannuma (Universal Geography) that was written by Katip Celebi and in the book Marifetname written by Ibrahim Hakki Erzurumlu, but these books are only partly geophysical books. In Istanbul the year 1868 is one of the most important for geophysical sciences because an observatory called Rasathane-i Amire was installed in the Pera region of this city. At this observatory the first systematic geophysical observations such as meteorological, seismological and even gravimetrical were made. There have been meteorological records in Anatolia since 1839. These are records of atmospheric temperature, pressure and humidity. In the Ottoman Empire, the science of geophysics is considered as one of the natural sciences along with astronomy, mineralogy, geology, etc., and these sciences are included as a part of physics and chemistry.

  8. Geochemical Analyses of Geologic Materials from Areas of Critical Environmental Concern, Clark and Nye Counties, Nevada

    Science.gov (United States)

    Ludington, Steve; Castor, Stephen B.; Budahn, James R.; Flynn, Kathryn S.

    2005-01-01

    INTRODUCTION An assessment of known and undiscovered mineral resources of selected areas administered by the Bureau of Land Management (BLM) in Clark and Nye Counties, Nevada was conducted by the U.S. Geological Survey (USGS), Nevada Bureau of Mines and Geology (NBMG), and University of Nevada, Las Vegas (UNLV). The purpose of this work was to provide the BLM with information for use in their long-term planning process in southern Nevada so that they can make better-informed decisions. The results of the assessment are in Ludington (2006). Existing information about the areas, including geology, geophysics, geochemistry, and mineral-deposit information was compiled, and field examinations of selected areas and mineral occurrences was conducted. This information was used to determine the geologic setting, metallogenic characteristics, and mineral potential of the areas. Twenty-five Areas of Critical Environmental Concern (ACECs) were identified by BLM as the object of this study. They range from tiny (less than one km2) to large (more than 1,000 km2). The location of the study areas is shown on Figure 1. This report includes geochemical data for rock samples collected by staff of the USGS and NBMG in these ACECs and nearby areas. Samples have been analyzed from the Big Dune, Ash Meadows, Arden, Desert Tortoise Conservation Center, Coyote Springs Valley, Mormon Mesa, Virgin Mountains, Gold Butte A and B, Whitney Pockets, Rainbow Gardens, River Mountains, and Piute-Eldorado Valley ACECs.

  9. Fundamentals of Geophysical Fluid Dynamics

    Science.gov (United States)

    McWilliams, James C.

    2006-07-01

    Earth's atmosphere and oceans exhibit complex patterns of fluid motion over a vast range of space and time scales. These patterns combine to establish the climate in response to solar radiation that is inhomogeneously absorbed by the materials comprising air, water, and land. Spontaneous, energetic variability arises from instabilities in the planetary-scale circulations, appearing in many different forms such as waves, jets, vortices, boundary layers, and turbulence. Geophysical fluid dynamics (GFD) is the science of all these types of fluid motion. This textbook is a concise and accessible introduction to GFD for intermediate to advanced students of the physics, chemistry, and/or biology of Earth's fluid environment. The book was developed from the author's many years of teaching a first-year graduate course at the University of California, Los Angeles. Readers are expected to be familiar with physics and mathematics at the level of general dynamics (mechanics) and partial differential equations. Covers the essential GFD required for atmospheric science and oceanography courses Mathematically rigorous, concise coverage of basic theory and applications to both oceans and atmospheres Author is a world expert; this book is based on the course he has taught for many years Exercises are included, with solutions available to instructors from solutions@cambridge.org

  10. A Spatially Constrained Multi-autoencoder Approach for Multivariate Geochemical Anomaly Recognition

    Science.gov (United States)

    Lirong, C.; Qingfeng, G.; Renguang, Z.; Yihui, X.

    2017-12-01

    Separating and recognizing geochemical anomalies from the geochemical background is one of the key tasks in geochemical exploration. Many methods have been developed, such as calculating the mean ±2 standard deviation, and fractal/multifractal models. In recent years, deep autoencoder, a deep learning approach, have been used for multivariate geochemical anomaly recognition. While being able to deal with the non-normal distributions of geochemical concentrations and the non-linear relationships among them, this self-supervised learning method does not take into account the spatial heterogeneity of geochemical background and the uncertainty induced by the randomly initialized weights of neurons, leading to ineffective recognition of weak anomalies. In this paper, we introduce a spatially constrained multi-autoencoder (SCMA) approach for multivariate geochemical anomaly recognition, which includes two steps: spatial partitioning and anomaly score computation. The first step divides the study area into multiple sub-regions to segregate the geochemical background, by grouping the geochemical samples through K-means clustering, spatial filtering, and spatial constraining rules. In the second step, for each sub-region, a group of autoencoder neural networks are constructed with an identical structure but different initial weights on neurons. Each autoencoder is trained using the geochemical samples within the corresponding sub-region to learn the sub-regional geochemical background. The best autoencoder of a group is chosen as the final model for the corresponding sub-region. The anomaly score at each location can then be calculated as the euclidean distance between the observed concentrations and reconstructed concentrations of geochemical elements.The experiments using the geochemical data and Fe deposits in the southwestern Fujian province of China showed that our SCMA approach greatly improved the recognition of weak anomalies, achieving the AUC of 0.89, compared

  11. The Legacy of Benoit Mandelbrot in Geophysics

    Science.gov (United States)

    Turcotte, D. L.

    2001-12-01

    The concept of fractals (fractional dimension) was introduced by Benoit Mandelbrot in his famous 1967 Science paper. The initial application was to the length of the coastline of Britain. A milestone in the appreciation of the fractal concept by geophysicists was the Union session of the AGU on fractals led off by Benoit in 1986. Although fractals have found important applications in almost every branch of the physical, biological, and social sciences, fractals have been particularly useful in geophysics. Drainage networks are fractal. The frequency-magnitude distribution of earthquakes is fractal. The scale invariance of landscapes and many other geological processes is due to the applicability of power-law (fractal) distributions. Clouds are often fractal. Porosity distributions are fractal. In an almost independent line of research, Benoit in collaboration with James Wallace and others developed the concept of self-affine fractals. The original applications were primarily to time series in hydrology and built on the foundation laid by Henry Hurst. Fractional Gaussian noises and fractional Brownian motions are ubiquitous in geophysics. These are expressed in terms of the power-law relation between the power-spectral density S and frequency f, S ~ f{ β }, examples are β = 0 (white noise), β = 1 (1/f noise), β = 2 (Brownian motion). Of particular importance in geophysics are fractional noises with β = 0.5, these are stationary but have long-range persistent and have a Hurst exponent H = 0.7. Examples include river flows, tree rings, sunspots, varves, etc. Two of Benoit Mandelbrot's major contributions in geophysics as in other fields are: (1) an appreciation of the importance of fat-tail, power-law (fractal) distributions and (2) an appreciation of the importance of self-similar long-range persistence in both stationary time series (noises) and nonstationary time series (walks).

  12. Geochemical and mineralogical characteristics of Lithomargic clay

    African Journals Online (AJOL)

    Administrator

    Geochemical and mineralogical characteristics of Lithomargic clay. GEOCHEMICAL AND .... tries, as filling material in the pulp and paper, toothpaste and paint industries as well ..... tions very vital to human health and other ac- tivities of man.

  13. NOAA and MMS Marine Minerals Geochemical Database

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Marine Minerals Geochemical Database was created by NGDC as a part of a project to construct a comprehensive computerized bibliography and geochemical database...

  14. Concerning evaluation of eco-geochemical background in remediation strategy

    Science.gov (United States)

    Korobova, Elena; Romanov, Sergey

    2015-04-01

    The geochemical concept of biosphere developed by V.I. Vernadsky states the geological role of the living organisms in the course of their active chemical interaction with the inert matter (Vernadsky, 1926, 1960). Basing on this theory it is reasonable to suggest that coevolution of living organisms and their environment led to development of the dynamically stable biogeocenoses precisely adequate to their geochemical environment. Soil cover was treated by V.I. Vernadsky as a balanced bio-inert matter resulting from this interaction. Appearance of human mind and then a civilization led to global expansion of human beings, first able to survive in unfavorable geochemical conditions and then starting chemical transformation of the environment to satisfy the growing demands of mankind in food and energy. The residence in unfavorable environment and local contamination was followed by appearance of endemic diseases of plants, animals and man. Therefore zonal, regional and local chemical composition of the soil cover formed in natural conditions may be used for estimation of the optimum geochemical background, most adequate for the corresponding zonal biogeocenoses and species. Moreover, the natural geochemical background and technogenic fields have unequal spatial structure and this facilitates their identification that may be relatively easy realized in remediation strategy. On the assumption of the foregoing, the adequate methodical approach to remediation of technogenically affected areas should account of the interaction of the existing natural and the newly formed technogenic geochemical fields and include the following steps: 1) the study and mapping of geochemical structure of the natural geochemical background basing on soil maps; 2) the study of contaminants and mapping spatial distribution of technogenic releases; 3) construction of risk maps for the target risk groups with due regard to natural ecological threshold concentration in context of risk degree for

  15. Oak Ridge Geochemical Reconnaissance Program

    International Nuclear Information System (INIS)

    Arendt, J.W.

    1977-03-01

    The Oak Ridge reconnaissance program is responsible for the geochemical survey in a 12-state area covering Texas, Oklahoma, Kansas, Nebraska, South Dakota, North Dakota, Minnesota, Wisconsin, Michigan, Iowa, Indiana, and Illinois as part of the National Uranium Resource Evaluation Program. The program concept is outlined and the planning and organization of the program is discussed

  16. Granite-repository - geochemical environment

    International Nuclear Information System (INIS)

    1979-04-01

    Some geochemical data of importance for a radioactive waste repository in hard rock are reviewed. The ground water composition at depth is assessed. The ground water chemistry in the vicinity of uranium ores is discussed. The redox system in Swedish bedrock is described. Influences of extreme climatic changes and of repository mining and construction are also evaluated

  17. Activities and Plan of the Center for Geophysics (Beijing from WDC to WDS

    Directory of Open Access Journals (Sweden)

    Fenglin Peng

    2013-01-01

    Full Text Available In this report we introduce the development of the WDC for Geophysics, Beijing included our activities in the electronic Geophysical Year (eGY and in the transition period from WDC to WDS. We also present our future plans. We have engaged in the development of geophysical informatics and related data science. We began the data visualization of geomagnetic fields in the GIS system. Our database has been expanded from geomagnetic data to the data of solid geophysics, including geothermal data, gravity data, and the records of aurora sightings in ancient China. We also joined the study of the history of the development of geophysics in China organized by the Chinese Geophysical Society (CGS.

  18. Review of geochemical measurement techniques for a nuclear waste repository in bedded salt

    International Nuclear Information System (INIS)

    Knauss, K.G.; Steinborn, T.L.

    1980-01-01

    A broad, general review is presented of geochemical measurement techniques that can provide data necessary for site selection and repository effectiveness assessment for a radioactive waste repository in bedded salt. The available measurement techniques are organized according to the parameter measured. The list of geochemical parameters include all those measurable geochemical properties of a sample whole values determine the geochemical characteristics or behavior of the system. For each technique, remarks are made pertaining to the operating principles of the measurement instrument and the purpose for which the technique is used. Attention is drawn to areas where further research and development are needed

  19. History of geophysical studies at the Waste Isolation Pilot Plant (WIPP), southeastern New Mexico

    International Nuclear Information System (INIS)

    Borns, D.J.

    1997-01-01

    A variety of geophysical methods including the spectrum of seismic, electrical, electromagnetic and potential field techniques have supported characterization, monitoring and experimental studies at the Waste Isolation Pilot Plant (WIPP). The geophysical studies have provided significant understanding of the nature of site deformation, tectonics and stability. Geophysical methods have delineated possible brine reservoirs beneath the underground facility and have defined the disturbed rock zone that forms around underground excavations. The role of geophysics in the WIPP project has evolved with the project. The early uses were for site characterization to satisfy site selection criteria or factors. As the regulatory framework for WIPP grew since 1980, the geophysics program supported experimental and field programs such as Salado hydrogeology and underground room systems and excavations. In summary, the major types of issues that geophysical studies addressed for WIPP are: Site Characterization; Castile Brine Reservoirs; Rustler/Dewey Lake Hydrogeology; Salado Hydrogeology; and Excavation Effects. The nature of geophysics programs for WIPP has been to support investigation rather than being the principal investigation itself. The geophysics program has been used to define conceptual models (e.g., the Disturbed Rock Zone-DRZ) or to test conceptual models (e.g., high transmissivity zones in the Rustler Formation). The geophysics program primarily supported larger characterization and experimental programs. Funding was not available for the complete documentation and interpretation. Therefore, a great deal of the geophysics survey information resides in contractor reports

  20. Basic elements of nuclear geophysics

    International Nuclear Information System (INIS)

    Nordemann, D.J.R.; Pereira, E.B.

    1984-01-01

    Nuclear Geophysics applies the nuclear radiation detection methodology to the geosciences, specially to study the dynamical processes of the lithosphere, the hydrosphere and the atmosphere as well as some aspects of planetology and astrophysics. Here the main methods are described: alpha-ray and gamma-ray spectrometry, the interaction of alpha and gamma radiation with matter and the detectors used (grid chambers, surface barrier silicon detector for alpha radiation; and sodium iodide thallium activated phosphors, hyperpure and lithium drifted germanium semiconductor detectors for gamma radiation). The principal applications of Nuclear Geophysics are given as examples to ilustrate the use of the methods described. (AUthor) [pt

  1. Geochemical engineering reference manual

    Energy Technology Data Exchange (ETDEWEB)

    Owen, L.B.; Michels, D.E.

    1984-01-01

    The following topics are included in this manual: physical and chemical properties of geothermal brine and steam, scale and solids control, processing spent brine for reinjection, control of noncondensable gas emissions, and goethermal mineral recovery. (MHR)

  2. Significance of geochemical characterization to performance at Yucca Mountain, Nevada

    International Nuclear Information System (INIS)

    Simmons, A.M.

    1993-01-01

    The U.S. concept for permanent disposal of high-level radioactive waste resembles those of other countries in that it relies upon burial in a deep geologic medium. This concept relies upon multiple barriers to retard transport of radionuclides to the accessible environment; those barriers consist of the waste form, waste container, engineered barrier system (including possible backfill) and retardant properties of the host rock. Because mobilization of radionuclides is fundamentally a geochemical problem, an understanding of past, present, and future geochemical processes is a requisite part of site characterization studies conducted by the U.S. Department of Energy at Yucca Mountain, Nevada. Geochemical information is needed for evaluating three favorable conditions (the rates of geochemical processes, conditions that promote precipitation or sorption of radionuclides or prohibit formation of colloids, and stable mineral assemblages) and four potentially adverse conditions of the site (groundwater conditions that could increase the chemical reactivity of the engineered barried system or reduce sorption, potential for gaseous radionuclide movement, and oxidizing groundwaters) for key issues of radionuclide release, groundwater quality, and stability of the geochemical environment. Preliminary results of long-term heating experiments indicate that although zeolites can be modified by long-term, low temperature reactions, their beneficial sorptive properties will not be adversely affected. Mineral reactions will be controlled by the aqueous activity of silica in groundwater with which the minerals are in contact. Geochemical barriers alone may satisfy release requirements to the accessible environment for many radionuclides; however, additional site specific geochemical and mineralogical data are needed to test existing and future radionuclide transport models

  3. Geochemical Exploration Techniques Applicable in the Search for Copper Deposits

    Science.gov (United States)

    Chaffee, Maurice A.

    1975-01-01

    Geochemical exploration is an important part of copper-resource evaluation. A large number of geochemical exploration techniques, both proved and untried, are available to the geochemist to use in the search for new copper deposits. Analyses of whole-rock samples have been used in both regional and local geochemical exploration surveys in the search for copper. Analyses of mineral separates, such as biotite, magnetite, and sulfides, have also been used. Analyses of soil samples are widely used in geochemical exploration, especially for localized surveys. It is important to distinguish between residual and transported soil types. Orientation studies should always be conducted prior to a geochemical investigation in a given area in order to determine the best soil horizon and the best size of soil material for sampling in that area. Silty frost boils, caliche, and desert varnish are specialized types of soil samples that might be useful sampling media. Soil gas is a new and potentially valuable geochemical sampling medium, especially in exploring for buried mineral deposits in arid regions. Gaseous products in samples of soil may be related to base-metal deposits and include mercury vapor, sulfur dioxide, hydrogen sulfide, carbon oxysulfide, carbon dioxide, hydrogen, oxygen, nitrogen, the noble gases, the halogens, and many hydrocarbon compounds. Transported materials that have been used in geochemical sampling programs include glacial float boulders, glacial till, esker gravels, stream sediments, stream-sediment concentrates, and lake sediments. Stream-sediment sampling is probably the most widely used and most successful geochemical exploration technique. Hydrogeochemical exploration programs have utilized hot- and cold-spring waters and their precipitates as well as waters from lakes, streams, and wells. Organic gel found in lakes and at stream mouths is an unproved sampling medium. Suspended material and dissolved gases in any type of water may also be useful

  4. Unleashing Geophysics Data with Modern Formats and Services

    Science.gov (United States)

    Ip, Alex; Brodie, Ross C.; Druken, Kelsey; Bastrakova, Irina; Evans, Ben; Kemp, Carina; Richardson, Murray; Trenham, Claire; Wang, Jingbo; Wyborn, Lesley

    2016-04-01

    Geoscience Australia (GA) is the national steward of large volumes of geophysical data extending over the entire Australasian region and spanning many decades. The volume and variety of data which must be managed, coupled with the increasing need to support machine-to-machine data access, mean that the old "click-and-ship" model delivering data as downloadable files for local analysis is rapidly becoming unviable - a "big data" problem not unique to geophysics. The Australian Government, through the Research Data Services (RDS) Project, recently funded the Australian National Computational Infrastructure (NCI) to organize a wide range of Earth Systems data from diverse collections including geoscience, geophysics, environment, climate, weather, and water resources onto a single High Performance Data (HPD) Node. This platform, which now contains over 10 petabytes of data, is called the National Environmental Research Data Interoperability Platform (NERDIP), and is designed to facilitate broad user access, maximise reuse, and enable integration. GA has contributed several hundred terabytes of geophysical data to the NERDIP. Historically, geophysical datasets have been stored in a range of formats, with metadata of varying quality and accessibility, and without standardised vocabularies. This has made it extremely difficult to aggregate original data from multiple surveys (particularly un-gridded geophysics point/line data) into standard formats suited to High Performance Computing (HPC) environments. To address this, it was decided to use the NERDIP-preferred Hierarchical Data Format (HDF) 5, which is a proven, standard, open, self-describing and high-performance format supported by extensive software tools, libraries and data services. The Network Common Data Form (NetCDF) 4 API facilitates the use of data in HDF5, whilst the NetCDF Climate & Forecasting conventions (NetCDF-CF) further constrain NetCDF4/HDF5 data so as to provide greater inherent interoperability

  5. Marine geophysical data management and presentation system

    Digital Repository Service at National Institute of Oceanography (India)

    Kunte, P.D.

    ) of the National Institute of Oceanography, Goa, India. GPDMPS is designed for the computerized storage retrieval and presentation of marine geophysical data and information. For the systematic management of geophysical data and information, GPDMPS is subdivided...

  6. Geophysical observations at cavity collapse

    Science.gov (United States)

    Jousset, Philippe; Bazargan-Sabet, Behrooz; Lebert, François; Bernardie, Séverine; Gourry, Jean-Christophe

    2010-05-01

    In Lorraine region (France) salt layers at about 200 meters depth are exploited by Solvay using solution mining methodology which consists in extracting the salt by dissolution, collapsing the cavern overburden during the exploitation phase and finally reclaiming the landscape by creating a water area. In this process, one of the main challenges for the exploiting company is to control the initial 120-m diameter collapse so as to minimize possible damages. In order to detect potential precursors and understand processes associated with such collapses, a wide series of monitoring techniques including micro seismics, broad-band seismology, hydro-acoustic, electromagnetism, gas probing, automatic leveling, continuous GPS, continuous gravity and borehole extensometry was set-up in the frame of an in-situ study carried out by the "Research Group for the Impact and Safety of Underground Works" (GISOS, France). Equipments were set-up well before the final collapse, giving a unique opportunity to analyze a great deal of information prior to and during the collapse process which has been successfully achieved on February the 13th, 2009 by controlling the cavity internal pressure. In this work, we present the results of data recorded by a network of 3 broadband seismometers, 2 accelerometers, 2 tilt-meters and a continuously gravity meter. We relate the variations of the brine pumping rate with the evolutions of the induced geophysical signals and finally we propose a first mechanical model for describing the controlled collapse. Beyond the studied case, extrapolation of the results obtained might contribute to the understanding of uncontrolled cavity collapses, such as pit-craters or calderas at volcanoes.

  7. Improved extraction of hydrologic information from geophysical data through coupled hydrogeophysical inversion

    Energy Technology Data Exchange (ETDEWEB)

    Hinnell, A.C.; Ferre, T.P.A.; Vrugt, J.A.; Huisman, J.A.; Moysey, S.; Rings, J.; Kowalsky, M.B.

    2009-11-01

    There is increasing interest in the use of multiple measurement types, including indirect (geophysical) methods, to constrain hydrologic interpretations. To date, most examples integrating geophysical measurements in hydrology have followed a three-step, uncoupled inverse approach. This approach begins with independent geophysical inversion to infer the spatial and/or temporal distribution of a geophysical property (e.g. electrical conductivity). The geophysical property is then converted to a hydrologic property (e.g. water content) through a petrophysical relation. The inferred hydrologic property is then used either independently or together with direct hydrologic observations to constrain a hydrologic inversion. We present an alternative approach, coupled inversion, which relies on direct coupling of hydrologic models and geophysical models during inversion. We compare the abilities of coupled and uncoupled inversion using a synthetic example where surface-based electrical conductivity surveys are used to monitor one-dimensional infiltration and redistribution.

  8. Conceptual Design of Geophysical Microsatellite

    Directory of Open Access Journals (Sweden)

    Matviyenko, S.A.

    2014-10-01

    Full Text Available The article covers the issue of Earth gravitational field (EGF parameters measurement from space. The radiophysical method of measurement of gravitational frequency shift of electromagnetic radiation using existent GNSS and its two variants are developed by the author. The designlayout drawing of geophysical microsatellite, which implements the radiophysical method of EGF measurement and provides Earth plasmasphere and magnetosphere monitoring, is offered.

  9. BROADBAND DIGITAL GEOPHYSICAL TELEMETRY SYSTEM.

    Science.gov (United States)

    Seeley, Robert L.; Daniels, Jeffrey J.

    1984-01-01

    A system has been developed to simultaneously sample and transmit digital data from five remote geophysical data receiver stations to a control station that processes, displays, and stores the data. A microprocessor in each remote station receives commands from the control station over a single telemetry channel.

  10. Geophysical borehole logging test procedure: Final draft

    International Nuclear Information System (INIS)

    1986-09-01

    The purpose of geophysical borehole logging from the At-Depth Facility (ADF) is to provide information which will assist in characterizing the site geologic conditions and in classifying the engineering characteristics of the rock mass in the vicinity of the ADF. The direct goals of borehole logging include identification of lithologic units and their correlation from hole to hole, identification of fractured or otherwise porous or permeable zones, quantitative or semi-quantitative estimation of various formation properties, and evaluation of factors such as the borehole diameter and orientation. 11 figs., 4 tabs

  11. Field Geophysics at SAGE: Strategies for Effective Education

    Science.gov (United States)

    Braile, L. W.; Baldridge, W. S.; Jiracek, G. R.; Biehler, S.; Ferguson, J. F.; Pellerin, L.; McPhee, D. K.; Bedrosian, P. A.; Snelson, C. M.; Hasterok, D. P.

    2011-12-01

    SAGE (Summer of Applied Geophysical Experience) is a unique program of education and research in geophysical field methods for undergraduate and graduate students from any university and for professionals. The core program is held for 4 weeks each summer in New Mexico and for an additional week in the following academic year in San Diego for U.S. undergraduates supported by the NSF Research Experience for Undergraduates (REU) program. Since SAGE was initiated in 1983, 730 students have participated in the program. NSF REU funding for SAGE began in 1990 and 319 REU students have completed SAGE through 2011. The primary objectives of SAGE are to teach the major geophysical exploration methods (seismic, gravity, magnetics, electromagnetics); apply these methods to the solution of specific problems (environmental, archaeological, hydrologic, geologic structure and stratigraphy); gain experience in processing, modeling and interpretation of geophysical data; and integrate the geophysical models and interpretations with geology. Additional objectives of SAGE include conducting research on the Rio Grande rift of northern New Mexico, and providing information on geophysics careers and professional development experiences to SAGE participants. Successful education, field and research strategies that we have implemented over the years include: 1. learn by doing; 2. mix lecture/discussion, field work, data processing and analysis, modeling and interpretation, and presentation of results; 3. a two-tier team approach - method/technique oriented teams and interpretation/integration teams (where each team includes persons representing different methods), provides focus, in-depth study, opportunity for innovation, and promotes teamwork and a multi-disciplinary approach; 4. emphasis on presentations/reports - each team (and all team members) make presentation, each student completes a written report; 5. experiment design discussion - students help design field program and consider

  12. Final Scientific/Technical Report – DE-EE0002960 Recovery Act. Detachment faulting and Geothermal Resources - An Innovative Integrated Geological and Geophysical Investigation of Pearl Hot Spring, Nevada

    Energy Technology Data Exchange (ETDEWEB)

    Stockli, Daniel F. [Univ. of Texas, Austin, TX (United States)

    2015-11-30

    The Pearl Host Spring Geothermal Project funded by the DoE Geothermal Program was a joint academic (KU/UT & OU) and industry collaboration (Sierra and Ram Power) to investigate structural controls and the importance of low-angle normal faults on geothermal fluid flow through a multifaceted geological, geophysical, and geochemical investigation in west-central Nevada. The study clearly showed that the geothermal resources in Clayton Valley are controlled by the interplay between low-angle normal faults and active deformation related to the Walker Lane. The study not only identified potentially feasible blind geothermal resource plays in eastern Clayton Valley, but also provide a transportable template for exploration in the area of west-central Nevada and other regional and actively-deforming releasing fault bends. The study showed that deep-seated low-angle normal faults likely act as crustal scale permeability boundaries and could play an important role in geothermal circulation and funneling geothermal fluid into active fault zones. Not unique to this study, active deformation is viewed as an important gradient to rejuvenated fracture permeability aiding the long-term viability of blind geothermal resources. The technical approach for Phase I included the following components, (1) Structural and geological analysis of Pearl Hot Spring Resource, (2) (U-Th)/He thermochronometry and geothermometry, (3) detailed gravity data and modeling (plus some magnetic and resistivity), (4) Reflection and Refraction Seismic (Active Source), (5) Integration with existing and new geological/geophysical data, and (6) 3-D Earth Model, combining all data in an innovative approach combining classic work with new geochemical and geophysical methodology to detect blind geothermal resources in a cost-effective fashion.

  13. Geophysical Institute. Biennial report, 1993-1994

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-01-01

    The 1993-1994 Geophysical Institute Biennial Report was published in November 1995 by the Geophysical Institute of the University of Alaska Fairbanks. It contains an overview of the Geophysical Institute, the Director`s Note, and research presentations concerning the following subjects: Scientific Predictions, Space Physics, Atmospheric Sciences, Snow, Ice and Permafrost, Tectonics and Sedimentation, Seismology, Volcanology, Remote Sensing, and other projects.

  14. Geophysical investigation and characterization with USRADS

    International Nuclear Information System (INIS)

    Flynn, C.R.; Blair, M.S.; Nyquist, J.E.

    1992-01-01

    This paper describes two recent case histories in which commercially available geophysical instruments were used with an innovative tracking and mapping system called USRADS (UltraSonic Ranging And Data System) that automates data location and collection. USRADS uses ultrasonics to provide real-time surveyor positioning and radio links to transmit the surveyor data to an on-site computer for storage and real-time display. USRADS uses a standard 386 computer for data collection and includes real-time color display of the findings. It also includes numerous analysis and display formats for on-site, as well as utilities to facilitate post-process analysis of the findings. The objective of one project was to locate several suspect waste disposal trenches and to map their boundaries. The second was to locate and map the presence of subsurface unexploded ordinance (UXO) at a suspect artillery impact area. A Geonics EM31 terrain conductivity meter interfaced to USRADS was used to map the suspect trenches. A Schonstedt GA-52C magnetometer interfaced to USRADS was used to map the subsurface UXO. Correlation of findings to known site features and additional knowledge about the sites indicates that these efforts did locate and map the geophysical features including the suspect waste trenches and the subsurface UXO. Images of the findings generated on-site and during post-processing are included

  15. Geophysics comes of age in oil sands development

    Energy Technology Data Exchange (ETDEWEB)

    Bauman, P. [WorleyParsons Komex, Calgary, AB (Canada); Birch, R.; Parker, D.; Andrews, B. [Calgary Univ., AB (Canada). Dept. of Geology and Geophysics

    2008-07-01

    This paper discussed geophysical techniques developed for oil sands exploration and production applications in Alberta's oil sands region. Geophysical methods are playing an important role in mine planning, tailings containment, water supply, and land reclamation activities. Geophysics techniques are used to estimate the volume of muskeg that needs to be stripped and stored for future reclamation activities as well as to site muskeg piles and delineate the thickness of clay Clearwater formations overlying Cretaceous oil-bearing sands. 2-D electrical resistivity mapping is used to map river-connected deep bedrock Pleistocene paleovalleys in the region. Geophysical studies are also used to investigate the interiors of dikes and berms as well as to monitor salt migration within tailings piles. Sonic and density logs are used to create synthetic seismograms for mapping the Devonian surface in the region. The new applications included the calculation of bitumen saturation from surface sands and shales; muskeg thickness mapping; and non-intrusive monitoring of leachate plumes. Geophysical techniques included 2-D electrical resistivity imaging; transient electromagnetic (EM) technologies; ground penetrating radar; and high-resolution seismic reflections. Polarization, surface nuclear magnetic resonance and push-probe sensing techniques were also discussed. Techniques were discussed in relation to Alberta's Athabasca oil sands deposits. 4 refs.

  16. The Expanding Marketplace for Applied Geophysics

    Science.gov (United States)

    Carlson, N.; Sirles, P.

    2012-12-01

    While the image of geophysics for the proverbial "layman" often seems limited to volcanoes and earthquakes, and to the geoscientist this image enlarges to include oil or minerals exploration and whole earth studies, there has been a steady increase in the application of geophysics into the realm of "daily life", such as real estate deals, highway infrastructure, and flood protection. This expansion of applications can be attributed to the improved economics from advances in equipment and interpretation. Traditional geophysical methods that at one time often only fit within the budgets of oil, gas, and minerals exploration programs can now be economically applied to much smaller scale needs like contaminant mapping, landfill delineation, and levee investigations. A real-world, economic example of this expanding marketplace is our company, which began very small and was aimed almost exclusively at the minerals exploration market. Most of our growth has been in the last 10 years, when we have expanded to five offices and a staff with almost 40 geoscientist degrees (21 in geophysics); much of this growth has been in the non-oil, non-minerals arenas. While much of our work still includes minerals exploration, other projects this year include wind-farm foundation studies, cavity detection above underground nuclear tests, landfill studies, acid mine drainage problems, and leaks in evaporation ponds. A methodology example of this expanding market is the induced polarization (IP) survey, once primarily used for minerals exploration, particularly large porphyry copper deposits, but now efficient enough to also use in environmental studies. The IP method has been particularly useful in delineating and characterizing old, poorly documented landfills, and recent research suggests it may also be useful in monitoring the accelerated biodegradation processes used in some cases to rehabilitate the sites. Compared to temperature monitoring systems, IP may be more useful in providing

  17. Alternative geochemical barrier materials

    International Nuclear Information System (INIS)

    1991-07-01

    Previous investigations of the effects of neutralization and reduction on uranium mill tailings pore fluids by the Technical Support Contractor indicated that arsenic, selenium, and molybdenum continue to remain in solution in all but reducing conditions. These hazardous constituents are present in groundwaters as oxyanions and, therefore, are not expected to be removed by adsorption into clays and most other soil constituents. It was decided to investigate the attenuation capacity of two commonly available crystalline iron oxides, taconite and scoria, and a zeolite, a network aluminosilicate with a cage structure. Columns of the candidate materials were exposed to solutions of individual constituents, including arsenic, molybdenum, selenium, and, uranium, and to the spiked tailings pore fluid from the Bodo Canyon disposal cell near Durango, Colorado. In addition to the single material columns, a homogeneous blend of the three materials and layers of the materials were exposed to spiked tailings pore fluids. The results of these experiments indicate that with the exception of molybdenum, the constituents of concern are attenuated by the taconite; however, they are not sufficiently attenuated to meet the groundwater protection standards applicable to the UMTRA Project. Therefore, the candidate barrier materials did not prove to be useful to the UMTRA Project for the cleanup of groundwaters

  18. Geochemical reanalysis of historical U.S. Geological Survey sediment samples from the northeastern Alaska Range, Healy, Mount Hayes, Nabesna, and Tanacross quadrangles, Alaska

    Science.gov (United States)

    Werdon, Melanie B.; Granitto, Matthew; Azain, Jaime S.

    2015-01-01

    The State of Alaska’s Strategic and Critical Minerals (SCM) Assessment project, a State-funded Capital Improvement Project (CIP), is designed to evaluate Alaska’s statewide potential for SCM resources. The SCM Assessment is being implemented by the Alaska Division of Geological & Geophysical Surveys (DGGS), and involves obtaining new airborne-geophysical, geological, and geochemical data. As part of the SCM Assessment, thousands of historical geochemical samples from DGGS, U.S. Geological Survey (USGS), and U.S. Bureau of Mines archives are being reanalyzed by DGGS using modern, quantitative, geochemical-analytical methods. The objective is to update the statewide geochemical database to more clearly identify areas in Alaska with SCM potential. The USGS is also undertaking SCM-related geologic studies in Alaska through the federally funded Alaska Critical Minerals cooperative project. DGGS and USGS share the goal of evaluating Alaska’s strategic and critical minerals potential and together created a Letter of Agreement (signed December 2012) and a supplementary Technical Assistance Agreement (#14CMTAA143458) to facilitate the two agencies’ cooperative work. Under these agreements, DGGS contracted the USGS in Denver to reanalyze historical USGS sediment samples from Alaska. For this report, DGGS funded reanalysis of 670 historical USGS sediment samples from the statewide Alaska Geochemical Database Version 2.0 (AGDB2; Granitto and others, 2013). Samples were chosen from the northeastern Alaska Range, in the Healy, Mount Hayes, Nabesna, and Tanacross quadrangles, Alaska (fig. 1). The USGS was responsible for sample retrieval from the National Geochemical Sample Archive (NGSA) in Denver, Colorado through the final quality assurance/quality control (QA/QC) of the geochemical analyses obtained through the USGS contract lab. The new geochemical data are published in this report as a coauthored DGGS report, and will be incorporated into the statewide geochemical

  19. Geochemical reanalysis of historical U.S. Geological Survey sediment samples from the Kougarok area, Bendeleben and Teller quadrangles, Seward Peninsula, Alaska

    Science.gov (United States)

    Werdon, Melanie B.; Granitto, Matthew; Azain, Jaime S.

    2015-01-01

    The State of Alaska’s Strategic and Critical Minerals (SCM) Assessment project, a State-funded Capital Improvement Project (CIP), is designed to evaluate Alaska’s statewide potential for SCM resources. The SCM Assessment is being implemented by the Alaska Division of Geological & Geophysical Surveys (DGGS), and involves obtaining new airborne-geophysical, geological, and geochemical data. As part of the SCM Assessment, thousands of historical geochemical samples from DGGS, U.S. Geological Survey (USGS), and U.S. Bureau of Mines archives are being reanalyzed by DGGS using modern, quantitative, geochemical-analytical methods. The objective is to update the statewide geochemical database to more clearly identify areas in Alaska with SCM potential. The USGS is also undertaking SCM-related geologic studies in Alaska through the federally funded Alaska Critical Minerals cooperative project. DGGS and USGS share the goal of evaluating Alaska’s strategic and critical minerals potential and together created a Letter of Agreement (signed December 2012) and a supplementary Technical Assistance Agreement (#14CMTAA143458) to facilitate the two agencies’ cooperative work. Under these agreements, DGGS contracted the USGS in Denver to reanalyze historical USGS sediment samples from Alaska. For this report, DGGS funded reanalysis of 302 historical USGS sediment samples from the statewide Alaska Geochemical Database Version 2.0 (AGDB2; Granitto and others, 2013). Samples were chosen from the Kougarok River drainage as well as smaller adjacent drainages in the Bendeleben and Teller quadrangles, Seward Peninsula, Alaska (fig. 1). The USGS was responsible for sample retrieval from the National Geochemical Sample Archive (NGSA) in Denver, Colorado through the final quality assurance/quality control (QA/QC) of the geochemical analyses obtained through the USGS contract lab. The new geochemical data are published in this report as a coauthored DGGS report, and will be incorporated

  20. Geophysical investigations in the Veitsivaara area, Finland summary report

    International Nuclear Information System (INIS)

    Heikkinen, E.; Saksa, P.; Hinkkanen, H.

    1991-10-01

    Teollisuuden Voima Oy (TVO carries out site investigations in Finland for final disposal of nuclear high level waste during 1987-2000. Investigations by geological, geophysical, geohydrological and geochemical methods were carried out in the Veitsivaara area in 1987-90 to determine the suitability of the bedrock for the final disposal of spent nuclear fuel. Airborne, ground and borehole geophysical methods were used to study the rock type distribution, fracturing and hydraulic conductivity. Airborne surveys were performed by magnetic, radiometric and two electromagnetic methods and ground investigations by VLF magnetic and resistivity, magnetic and impulse radar methods. Electromagnetic and seismic refraction surveys were used to locate crushed and fracture zones. The properties of weak electrical conductors, e.g. their depth dimensions, were studied by direct current resistivity measurements. The rock type distribution was studied by single-hole logging of susceptibility, natural γ-radiation and radiometric γ γ-density. Electrical and acoustic logging allowed water bearing fractures to be mapped and the results of water injection tests to be interpreted. Flow conditions in the boreholes were studied by both fluid logging and tube wave sounding

  1. Archean crust-mantle geochemical differentiation

    Science.gov (United States)

    Tilton, G. R.

    Isotope measurements on carbonatite complexes and komatiites can provide information on the geochemical character and geochemical evolution of the mantle, including the sub-continental mantle. Measurements on young samples establish the validity of the method. These are based on Sr, Nd and Pb data from the Tertiary-Mesozoic Gorgona komatiite and Sr and Pb data from the Cretaceous Oka carbonatite complex. In both cases the data describe a LIL element-depleted source similar to that observed presently in MORB. Carbonatite data have been used to study the mantle beneath the Superior Province of the Canadian Shield one billion years (1 AE) ago. The framework for this investigation was established by Bell et al., who showed that large areas of the province appear to be underlain by LIL element-depleted mantle (Sr-85/Sr-86=0.7028) at 1 AE ago. Additionally Bell et al. found four complexes to have higher initial Sr ratios (Sr-87/Sr-86=0.7038), which they correlated with less depleted (bulk earth?) mantle sources, or possibly crustal contamination. Pb isotope relationships in four of the complexes have been studied by Bell et al.

  2. Archean crust-mantle geochemical differentiation

    Science.gov (United States)

    Tilton, G. R.

    1983-01-01

    Isotope measurements on carbonatite complexes and komatiites can provide information on the geochemical character and geochemical evolution of the mantle, including the sub-continental mantle. Measurements on young samples establish the validity of the method. These are based on Sr, Nd and Pb data from the Tertiary-Mesozoic Gorgona komatiite and Sr and Pb data from the Cretaceous Oka carbonatite complex. In both cases the data describe a LIL element-depleted source similar to that observed presently in MORB. Carbonatite data have been used to study the mantle beneath the Superior Province of the Canadian Shield one billion years (1 AE) ago. The framework for this investigation was established by Bell et al., who showed that large areas of the province appear to be underlain by LIL element-depleted mantle (Sr-85/Sr-86=0.7028) at 1 AE ago. Additionally Bell et al. found four complexes to have higher initial Sr ratios (Sr-87/Sr-86=0.7038), which they correlated with less depleted (bulk earth?) mantle sources, or possibly crustal contamination. Pb isotope relationships in four of the complexes have been studied by Bell et al.

  3. The Role of Geophysics/Geology in the Environmental Discourse

    Science.gov (United States)

    Pfannkuch, H. O.

    2013-12-01

    Environmental problems are created by interaction between the Anthroposphere and Geosphere. Principles and laws governing behavior and interaction between them have to be fully understood to properly address environmental problems. A particular problem arises by inadequate communication between practitioners and/or decision makers in each sphere. A perfect analysis or solution in the Geosphere based solely on geophysical, geochemical principles will go nowhere if institutional, socio economic principles are ignored, or vice versa: no matter how well socio-economic relations are used in the Anthroposphere if they violate basic laws of physics . Two conceptual representations of the environment system are: Nöosphere with three domains: Physical, Institutional, Symbolic and their interactions. It is where environmental problems arise, decisions are made and implemented. The Physical Domain comprises physical, chemical, biological, geopsphere realities. Problems are treated by the scientific method. The Institutional Domain with economy, sociology, administration and political institutions, solves by negotiation (vote, ballot). The elements of the Symbolic Domain. spiritual, moral, religious, esthetic principles are revealed. All are intimately connected and interdependent. Activity in one affects the state of the others. A particularly strong and effective interactive relation exists between the Physical and the Institutional domains with regards to environmental problem definition, analysis and resolution. Hierarchic structure of interaction pyramid. Geosphere, Biosphere and Anthroposphere are open systems and are organized in successive levels forming a pyramid shape or aspect. The Geosphere forms the bottom level, the Anthroposphere the top. One fundamental attribute is that level (n) is limited by the restrictions obtaining in level (n-1), and conversely, level (n) represents the restrictions and limitations for level (n+1). In the environmental discourse this

  4. Overview of geochemical modeling needs for nuclear waste management

    International Nuclear Information System (INIS)

    Isherwood, D.J.; Wolery, T.J.

    1985-01-01

    Geochemical modeling needs for nuclear waste management are discussed with an emphasis on data base development and computer code. Other areas for future research include: precipitation kinetics, fixed fugacity, sorption, glasslt. slashwater interactions, redox disequilibrium and kinetics, radiolysis, solid solutions, and isotopic fractionation. 15 references

  5. The teaching of geophysics in Latin America: An updated assessment

    Science.gov (United States)

    Valencio, Daniel A.; Schneider, Otto

    The situation of geophysics in developing countries has been the subject of discussions and analysis by diverse international organizations. It was also discussed in some articles in Eos [e.g., Lomnitz, 1982; Urrutia Fucugauchi, 1982; Bolt, 1982]. We have been requested to contribute a current evaluation of the problem, with particular reference to geophysical education in Latin America.In the following report on specialized training of geophysicists in Latin American countries, we consider the “exact earth sciences” in the broader sense, i.e., the mathematical and physical (and, to a certain extent, chemical) aspects of the planet earth as a whole, including its fluid portions, as opposed to the more restricted concept of just solid earth geophysics. In other words, our inquiry follows the scope of both AGU and the International Union of Geodesy and Geophysics (IUGG), so geodesy, although not explicitly covered, will still be mentioned occasionally. We will also consider the applied branches, especially exploration geophysics, since these areas furnish powerful motivation for fostering our sciences, both in the governmental circles of developing countries and among the young people looking for a promising professional future.

  6. New perspectives on superparameterization for geophysical turbulence

    International Nuclear Information System (INIS)

    Majda, Andrew J.; Grooms, Ian

    2014-01-01

    This is a research expository paper regarding superparameterization, a class of multi-scale numerical methods designed to cope with the intermittent multi-scale effects of inhomogeneous geophysical turbulence where energy often inverse-cascades from the unresolved scales to the large scales through the effects of waves, jets, vortices, and latent heat release from moist processes. Original as well as sparse space–time superparameterization algorithms are discussed for the important case of moist atmospheric convection including the role of multi-scale asymptotic methods in providing self-consistent constraints on superparameterization algorithms and related deterministic and stochastic multi-cloud parameterizations. Test models for the statistical numerical analysis of superparameterization algorithms are discussed both to elucidate the performance of the basic algorithms and to test their potential role in efficient multi-scale data assimilation. The very recent development of grid-free seamless stochastic superparameterization methods for geophysical turbulence appropriate for “eddy-permitting” mesoscale ocean turbulence is presented here including a general formulation and illustrative applications to two-layer quasigeostrophic turbulence, and another difficult test case involving one-dimensional models of dispersive wave turbulence. This last test case has randomly generated solitons as coherent structures which collapse and radiate wave energy back to the larger scales, resulting in strong direct and inverse turbulent energy cascades

  7. Geophysical interpretation using integral equations

    CERN Document Server

    Eskola, L

    1992-01-01

    Along with the general development of numerical methods in pure and applied to apply integral equations to geophysical modelling has sciences, the ability improved considerably within the last thirty years or so. This is due to the successful derivation of integral equations that are applicable to the modelling of complex structures, and efficient numerical algorithms for their solution. A significant stimulus for this development has been the advent of fast digital computers. The purpose of this book is to give an idea of the principles by which boundary-value problems describing geophysical models can be converted into integral equations. The end results are the integral formulas and integral equations that form the theoretical framework for practical applications. The details of mathematical analysis have been kept to a minimum. Numerical algorithms are discussed only in connection with some illustrative examples involving well-documented numerical modelling results. The reader is assu­ med to have a back...

  8. Geophysical and solar activity indices

    Science.gov (United States)

    Bossy, L.; Lemaire, J.

    1984-04-01

    A large number of geophysicists try to correlate their observations with one or even a series of different geophysical or solar activity indices. Yet the right choice of the most appropriate index with which to correlate depends mainly on our understanding of the physical cause-effect relationship between the new set of observations and the index chosen. This best choice will therefore depend on our good understanding of the methods of measurement and derivation of the adopted index in such correlative studies. It relies also on our awareness of the range of applicability of the indices presently available as well as on our understanding of their limitations. It was to achieve these goals that a series of general lectures on geophysical and solar activity indices was organized by L. Bossy and J. Lemaire (Institut d'Aeronomie Spatiale de Belgique (IASB), Brussels), March 26-29, 1984 at Han-sur-Lesse, Belgium.

  9. Mathematics applied to nuclear geophysics

    International Nuclear Information System (INIS)

    Pereira, E.B.; Nordemann, D.J.R.

    1987-01-01

    One of the powerful auxiliary to nuclear geophysics is the obtention and interpretation of the alpha and gamma radiation spectra. This work discuss, qualitative and quantitative, the lost information problem, motivated by the noise in the process of information codification. The decodification process must be suppield by the appropriate mathematical model on the measure system to recovery the information from nuclear source. (C.D.G.) [pt

  10. Geophysical methods in uranium mining

    International Nuclear Information System (INIS)

    Koehler, K.

    1989-01-01

    In uranium prospecting, exploration, milling, and mining there is an urgent need to have information on the concentration of uranium at all steps of handling uranium containing materials. To gain this information in an effective way modern geophysical methods have to be applied. Publications of the IAEA and NEA in this field are reviewed in order to characterize the state of the art of these methods. 55 refs

  11. Integrated geophysical surveys for searching of podiform chromite in Albania

    Energy Technology Data Exchange (ETDEWEB)

    Kospiri, Aleksander; Zajmi, Asim [Geophysical and Geochemical Center, Tirana (Albania)

    1995-12-31

    The purpose of this paper is to describe the application of geophysical methods to the search for chromite in Albania. Albania is well known for its chromite resources and ranks third amongst world producers of high-quality chromite. The ultramafic massif of Bulqiza, is the most important chromite bearing one. Surveying a surface of about 120 square kilometers (30% of massifs area) in that massif with integrated geophysical methods a considerable number of targets has been discovered, from which some are already objects under mine activity. In the integrated methods for chromite exploration in Bulqiza ultramafic massif are included: geological, gravity, magnetic and electrical mapping of the scale 1:2000 with survey grids 40x20m, 20x5m. Based on the interpretations of geophysical exploration were projected drilling which led to the discovery of some big ore deposits. (author). 12 refs., 3 figs

  12. The Nirex Sellafield site investigation: the role of geophysical interpretation

    International Nuclear Information System (INIS)

    Muir Wood, R.; Woo, G.; MacMillan, G.

    1992-01-01

    This report reviews the methods by which geophysical data are interpreted, and used to characterize the 3-D geology of a site for potential storage of radioactive waste. The report focuses on the NIREX site investigation at Sellafield, for which geophysical observations provide a significant component of the structural geological understanding. In outlining the basic technical principles of seismic data processing and interpretation, and borehole logging, an attempt has been made to identify errors, uncertainties, and the implicit use of expert judgement. To enhance the reliability of a radiological probabilistic risk assessment, recommendations are proposed for independent use of the primary NIREX geophysical site investigation data in characterizing the site geology. These recommendations include quantitative procedures for undertaking an uncertainty audit using a combination of statistical analysis and expert judgement. (author)

  13. Soil Iodine Determination in Deccan Syneclise, India: Implications for Near Surface Geochemical Hydrocarbon Prospecting

    International Nuclear Information System (INIS)

    Mani, Devleena; Kumar, T. Satish; Rasheed, M. A.; Patil, D. J.; Dayal, A. M.; Rao, T. Gnaneshwar; Balaram, V.

    2011-01-01

    The association of iodine with organic matter in sedimentary basins is well documented. High iodine concentration in soils overlying oil and gas fields and areas with hydrocarbon microseepage has been observed and used as a geochemical exploratory tool for hydrocarbons in a few studies. In this study, we measure iodine concentration in soil samples collected from parts of Deccan Syneclise in the west central India to investigate its potential application as a geochemical indicator for hydrocarbons. The Deccan Syneclise consists of rifted depositional sites with Gondwana–Mesozoic sediments up to 3.5 km concealed under the Deccan Traps and is considered prospective for hydrocarbons. The concentration of iodine in soil samples is determined using ICP-MS and the values range between 1.1 and 19.3 ppm. High iodine values are characteristic of the northern part of the sampled region. The total organic carbon (TOC) content of the soil samples range between 0.1 and 1.3%. The TOC correlates poorly with the soil iodine (r 2 < 1), indicating a lack of association of iodine with the surficial organic matter and the possibility of interaction between the seeping hydrocarbons and soil iodine. Further, the distribution pattern of iodine compares well with two surface geochemical indicators: the adsorbed light gaseous hydrocarbons (methane through butane) and the propane-oxidizing bacterial populations in the soil. The integration of geochemical observations show the occurrence of elevated values in the northern part of the study area, which is also coincident with the presence of exposed dyke swarms that probably serve as conduits for hydrocarbon microseepage. The corroboration of iodine with existing geological, geophysical, and geochemical data suggests its efficacy as one of the potential tool in surface geochemical exploration of hydrocarbons. Our study supports Deccan Syneclise to be promising in terms of its hydrocarbon prospects.

  14. A geochemical atlas of North Carolina, USA

    Science.gov (United States)

    Reid, J.C.

    1993-01-01

    A geochemical atlas of North Carolina, U.S.A., was prepared using National Uranium Resource Evaluation (NURE) stream-sediment data. Before termination of the NURE program, sampling of nearly the entire state (48,666 square miles of land area) was completed and geochemical analyses were obtained. The NURE data are applicable to mineral exploration, agriculture, waste disposal siting issues, health, and environmental studies. Applications in state government include resource surveys to assist mineral exploration by identifying geochemical anomalies and areas of mineralization. Agriculture seeks to identify areas with favorable (or unfavorable) conditions for plant growth, disease, and crop productivity. Trace elements such as cobalt, copper, chromium, iron, manganese, zinc, and molybdenum must be present within narrow ranges in soils for optimum growth and productivity. Trace elements as a contributing factor to disease are of concern to health professionals. Industry can use pH and conductivity data for water samples to site facilities which require specific water quality. The North Carolina NURE database consists of stream-sediment samples, groundwater samples, and stream-water analyses. The statewide database consists of 6,744 stream-sediment sites, 5,778 groundwater sample sites, and 295 stream-water sites. Neutron activation analyses were provided for U, Br, Cl, F, Mn, Na, Al, V, Dy in groundwater and stream water, and for U, Th, Hf, Ce, Fe, Mn, Na, Sc, Ti, V, Al, Dy, Eu, La, Sm, Yb, and Lu in stream sediments. Supplemental analyses by other techniques were reported on U (extractable), Ag, As, Ba, Be, Ca, Co, Cr, Cu, K, Li, Mg, Mo, Nb, Ni, P, Pb, Se, Sn, Sr, W, Y, and Zn for 4,619 stream-sediment samples. A small subset of 334 stream samples was analyzed for gold. The goal of the atlas was to make available the statewide NURE data with minimal interpretation to enable prospective users to modify and manipulate the data for their end use. The atlas provides only

  15. Effect of source integration on the geochemical fluxes from springs

    International Nuclear Information System (INIS)

    Frisbee, Marty D.; Phillips, Fred M.; White, Art F.; Campbell, Andrew R.; Liu, Fengjing

    2013-01-01

    Geochemical fluxes from watersheds are typically defined using mass-balance methods that essentially lump all weathering processes operative in a watershed into a single flux of solute mass measured in streamflow at the watershed outlet. However, it is important that we understand how weathering processes in different hydrological zones of a watershed (i.e., surface, unsaturated, and saturated zones) contribute to the total geochemical flux from the watershed. This capability will improve understanding of how geochemical fluxes from these different zones may change in response to climate change. Here, the geochemical flux from weathering processes occurring solely in the saturated zone is investigated. This task, however, remains exceedingly difficult due to the sparsity of subsurface sampling points, especially in large, remote, and/or undeveloped watersheds. In such cases, springflow is often assumed to be a proxy for groundwater (defined as water residing in fully saturated geologic formations). However, springflow generation may integrate different sources of water including, but not limited to, groundwater. The authors’ hypothesis is that long-term estimates of geochemical fluxes from groundwater using springflow proxies will be too large due to the integrative nature of springflow generation. Two conceptual models of springflow generation are tested using endmember mixing analyses (EMMA) on observations of spring chemistries and stable isotopic compositions in a large alpine watershed in the San Juan Mountains of southwestern Colorado. In the “total springflow” conceptual model, springflow is assumed to be 100% groundwater. In the “fractional springflow” conceptual model, springflow is assumed to be an integration of different sources of water (e.g., groundwater, unsaturated flow, preferential flow in the soil, etc.) and groundwater is only a fractional component. The results indicate that groundwater contributions in springflow range from 2% to 100

  16. Mapping Neogene and Quaternary sedimentary deposits in northeastern Brazil by integrating geophysics, remote sensing and geological field data

    Science.gov (United States)

    Andrades-Filho, Clódis de Oliveira; Rossetti, Dilce de Fátima; Bezerra, Francisco Hilario Rego; Medeiros, Walter Eugênio; Valeriano, Márcio de Morisson; Cremon, Édipo Henrique; Oliveira, Roberto Gusmão de

    2014-12-01

    Neogene and late Quaternary sedimentary deposits corresponding respectively to the Barreiras Formation and Post-Barreiras Sediments are abundant along the Brazilian coast. Such deposits are valuable for reconstructing sea level fluctuations and recording tectonic reactivation along the passive margin of South America. Despite this relevance, much effort remains to be invested in discriminating these units in their various areas of occurrence. The main objective of this work is to develop and test a new methodology for semi-automated mapping of Neogene and late Quaternary sedimentary deposits in northeastern Brazil integrating geophysical and remote sensing data. The central onshore Paraíba Basin was selected due to the recent availability of a detailed map based on the integration of surface and subsurface geological data. We used airborne gamma-ray spectrometry (i.e., potassium-K and thorium-Th concentration) and morphometric data (i.e., relief-dissection, slope and elevation) extracted from the digital elevation model (DEM) generated by the Shuttle Radar Topography Mission (SRTM). The procedures included: (a) data integration using geographic information systems (GIS); (b) exploratory statistical analyses, including the definition of parameters and thresholds for class discrimination for a set of sample plots; and (c) development and application of a decision-tree classification. Data validation was based on: (i) statistical analysis of geochemical and airborne gamma-ray spectrometry data consisting of K and Th concentrations; and (ii) map validation with the support of a confusion matrix, overall accuracy, as well as quantity disagreement and allocation disagreement for accuracy assessment based on field points. The concentration of K successfully separated the sedimentary units of the basin from Precambrian basement rocks. The relief-dissection morphometric variable allowed the discrimination between the Barreiras Formation and the Post-Barreiras Sediments. In

  17. Novel Geochemical Techniques Integrated In Exploration for Uranium Deposits at Depth

    International Nuclear Information System (INIS)

    Kyser, Kurt

    2014-01-01

    Recent results in the use of geochemistry in detecting deep uranium deposits: (1) Map element distributions in and around deposits to assess the total chemical environment associated with the deposit, (2) Use element tracing with isotopic compositions in surface media to detect specific components from uranium deposits at depth, (3) Capitalize on element mobility across the geosphere-biosphere interface to enhance exploration using select media, (4) Geochemical data from drill core or surface media can enhance target identification when integrated with geophysical data.

  18. Geophysical Study of Lithologies Attributes At Isihor Village, Edo ...

    African Journals Online (AJOL)

    These attributes include depth, thickness of lithologies or rock types beneath the sea level or earth's surface. Geophysical prospect of lithologies in this studied area is vital for many economic and environmental reasons for examples a large portion of the world's fossil fuels such as oil, gas and coal are found in stratified ...

  19. Status report on geochemical modelling

    International Nuclear Information System (INIS)

    Read, D.

    1991-12-01

    This report describes the findings of a review undertaken on behalf of the project management group of the programme 'Endlagersicherheit in der Nachbetriebsphase' based at GSF-IfT (Forschungszentrum fuer Umwelt und Gesundheit - Institut fuer Tieflagerung) to establish the current status of research into the simulation of geochemical processes relevant to radiological assessment. The review is intended to contribute to Stage 1 of a strategy formulated to enhance the use of geochemical models in Germany. Emphasis has been placed on processes deemed to be of greatest relevance to performance assessment for a HLW-repository in a salt dome principally, speciation-solubility in high salinity solutions, complexation by natural organics and generation-transport of colloids. For each of these and other topics covered, a summary is given of fundamental concepts, theoretical representations and their limitations, highlighting, where appropriate, the advantages and disadvantages of alternative approaches. The availability of data to quantify any given representation is addressed, taking into account the need for information at elevated temperatures and pressures. Mass transfer is considered in terms of aqueous, particulate and gas-mediated transport, respectively. (orig.) [de

  20. Monitoring super-volcanoes: geophysical and geochemical signals at Yellowstone and other large caldera systems.

    Science.gov (United States)

    Lowenstern, Jacob B; Smith, Robert B; Hill, David P

    2006-08-15

    Earth's largest calderas form as the ground collapses during immense volcanic eruptions, when hundreds to thousands of cubic kilometres of magma are explosively withdrawn from the Earth's crust over a period of days to weeks. Continuing long after such great eruptions, the resulting calderas often exhibit pronounced unrest, with frequent earthquakes, alternating uplift and subsidence of the ground, and considerable heat and mass flux. Because many active and extinct calderas show evidence for repetition of large eruptions, such systems demand detailed scientific study and monitoring. Two calderas in North America, Yellowstone (Wyoming) and Long Valley (California), are in areas of youthful tectonic complexity. Scientists strive to understand the signals generated when tectonic, volcanic and hydrothermal (hot ground water) processes intersect. One obstacle to accurate forecasting of large volcanic events is humanity's lack of familiarity with the signals leading up to the largest class of volcanic eruptions. Accordingly, it may be difficult to recognize the difference between smaller and larger eruptions. To prepare ourselves and society, scientists must scrutinize a spectrum of volcanic signals and assess the many factors contributing to unrest and toward diverse modes of eruption.

  1. Marine Geology and Geophysics Field Course Offered by The University of Texas Institute for Geophysics

    Science.gov (United States)

    Duncan, D.; Davis, M. B.; Allison, M. A.; Gulick, S. P.; Goff, J. A.; Saustrup, S.

    2012-12-01

    The University of Texas Institute for Geophysics, part of the Jackson School of Geosciences, annually offers an intensive three-week marine geology and geophysics field course during the spring-summer intersession. Now in year six, the course provides hands-on instruction and training for graduate and upper-level undergraduate students in data acquisition, processing, interpretation, and visualization. Techniques covered include high-resolution seismic reflection, CHIRP sub-bottom profiling, multibeam bathymetry, sidescan sonar, several types of sediment coring, grab sampling, and the sedimentology of resulting seabed samples (e.g., core description, grain size analysis, x-radiography, etc.). Students participate in an initial period of classroom instruction designed to communicate geological context of the field area (which changes each year) along with theoretical and technical background on each field method. The class then travels to the Gulf Coast for a week of at-sea field work. Our field sites at Port Aransas and Galveston, Texas, and Grand Isle, Louisiana, have provided ideal locations for students to investigate coastal and sedimentary processes of the Gulf Coast and continental shelf through application of geophysical techniques. In the field, students rotate between two research vessels: one vessel, the 22' aluminum-hulled R/V Lake Itasca, owned and operated by UTIG, is used principally for multibeam bathymetry, sidescan sonar, and sediment sampling; the other, NOAA's R/V Manta or the R/V Acadiana, operated by the Louisiana Universities Marine Consortium, and is used primarily for high-resolution seismic reflection, CHIRP sub-bottom profiling, multibeam bathymetry, gravity coring, and vibrocoring. While at sea, students assist with survey design, learn instrumentation set up, acquisition parameters, data quality control, and safe instrument deployment and retrieval. In teams of three, students work in onshore field labs preparing sediment samples for

  2. Coupled geochemical and solute transport code development

    International Nuclear Information System (INIS)

    Morrey, J.R.; Hostetler, C.J.

    1985-01-01

    A number of coupled geochemical hydrologic codes have been reported in the literature. Some of these codes have directly coupled the source-sink term to the solute transport equation. The current consensus seems to be that directly coupling hydrologic transport and chemical models through a series of interdependent differential equations is not feasible for multicomponent problems with complex geochemical processes (e.g., precipitation/dissolution reactions). A two-step process appears to be the required method of coupling codes for problems where a large suite of chemical reactions must be monitored. Two-step structure requires that the source-sink term in the transport equation is supplied by a geochemical code rather than by an analytical expression. We have developed a one-dimensional two-step coupled model designed to calculate relatively complex geochemical equilibria (CTM1D). Our geochemical module implements a Newton-Raphson algorithm to solve heterogeneous geochemical equilibria, involving up to 40 chemical components and 400 aqueous species. The geochemical module was designed to be efficient and compact. A revised version of the MINTEQ Code is used as a parent geochemical code

  3. Stochastic resonance for exploration geophysics

    OpenAIRE

    Omerbashich, Mensur

    2008-01-01

    Stochastic resonance (SR) is a phenomenon in which signal to noise (SN) ratio gets improved by noise addition rather than removal as envisaged classically. SR was first claimed in climatology a few decades ago and then in other disciplines as well. The same as it is observed in natural systems, SR is used also for allowable SN enhancements at will. Here I report a proof of principle that SR can be useful in exploration geophysics. For this I perform high frequency GaussVanicek variance spectr...

  4. Geochemical prospecting for uranium and thorium deposits

    International Nuclear Information System (INIS)

    Boyle, R.W.

    1980-01-01

    A brief review of analytical geochemical prospecting methods for uranium and thorium is given excluding radiometric techniques, except those utilized in the determination of radon. The indicator (pathfinder) elements useful in geochemical surveys are listed for each of the types of known uranium and thorium deposits; this is followed by sections on analytical geochemical surveys based on rocks (lithochemical surveys), unconsolidated materials (pedochemical surveys), natural waters and sediments (hydrochemical surveys), biological materials (biogeochemical surveys) and gases (atmochemical surveys). All of the analytical geochemical methods are applicable in prospecting for thorium and uranium, particularly where radiometric methods fail due to attenuation by overburden, water, deep leaching and so on. Efficiency in the discovery of uranium and/or thorium orebodies is promoted by an integrated methods approach employing geological pattern recognition in the localization of deposits, analytical geochemical surveys, and radiometric surveys. (author)

  5. Institute of Geophysics, Planetary Physics, and Signatures

    Data.gov (United States)

    Federal Laboratory Consortium — The Institute of Geophysics, Planetary Physics, and Signatures at Los Alamos National Laboratory is committed to promoting and supporting high quality, cutting-edge...

  6. Validation of the WATEQ4 geochemical model for uranium

    International Nuclear Information System (INIS)

    Krupka, K.M.; Jenne, E.A.; Deutsch, W.J.

    1983-09-01

    As part of the Geochemical Modeling and Nuclide/Rock/Groundwater Interactions Studies Program, a study was conducted to partially validate the WATEQ4 aqueous speciation-solubility geochemical model for uranium. The solubility controls determined with the WATEQ4 geochemical model were in excellent agreement with those laboratory studies in which the solids schoepite [UO 2 (OH) 2 . H 2 O], UO 2 (OH) 2 , and rutherfordine ((UO 2 CO 3 ) were identified as actual solubility controls for uranium. The results of modeling solution analyses from laboratory studies of uranyl phosphate solids, however, identified possible errors in the characterization of solids in the original solubility experiments. As part of this study, significant deficiencies in the WATEQ4 thermodynamic data base for uranium solutes and solids were corrected. Revisions included recalculation of selected uranium reactions. Additionally, thermodynamic data for the hydroxyl complexes of U(VI), including anionic (VI) species, were evaluated (to the extent permitted by the available data). Vanadium reactions were also added to the thermodynamic data base because uranium-vanadium solids can exist in natural ground-water systems. This study is only a partial validation of the WATEQ4 geochemical model because the available laboratory solubility studies do not cover the range of solid phases, alkaline pH values, and concentrations of inorganic complexing ligands needed to evaluate the potential solubility of uranium in ground waters associated with various proposed nuclear waste repositories. Further validation of this or other geochemical models for uranium will require careful determinations of uraninite solubility over the pH range of 7 to 10 under highly reducing conditions and of uranyl hydroxide and phosphate solubilities over the pH range of 7 to 10 under oxygenated conditions

  7. Geophysical monitoring and reactive transport modeling of ureolytically-driven calcium carbonate precipitation

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Y.; Ajo-Franklin, J.B.; Spycher, N.; Hubbard, S.S.; Zhang, G.; Williams, K.H.; Taylor, J.; Fujita, Y.; Smith, R.

    2011-07-15

    Ureolytically-driven calcium carbonate precipitation is the basis for a promising in-situ remediation method for sequestration of divalent radionuclide and trace metal ions. It has also been proposed for use in geotechnical engineering for soil strengthening applications. Monitoring the occurrence, spatial distribution, and temporal evolution of calcium carbonate precipitation in the subsurface is critical for evaluating the performance of this technology and for developing the predictive models needed for engineering application. In this study, we conducted laboratory column experiments using natural sediment and groundwater to evaluate the utility of geophysical (complex resistivity and seismic) sensing methods, dynamic synchrotron x-ray computed tomography (micro-CT), and reactive transport modeling for tracking ureolytically-driven calcium carbonate precipitation processes under site relevant conditions. Reactive transport modeling with TOUGHREACT successfully simulated the changes of the major chemical components during urea hydrolysis. Even at the relatively low level of urea hydrolysis observed in the experiments, the simulations predicted an enhanced calcium carbonate precipitation rate that was 3-4 times greater than the baseline level. Reactive transport modeling results, geophysical monitoring data and micro-CT imaging correlated well with reaction processes validated by geochemical data. In particular, increases in ionic strength of the pore fluid during urea hydrolysis predicted by geochemical modeling were successfully captured by electrical conductivity measurements and confirmed by geochemical data. The low level of urea hydrolysis and calcium carbonate precipitation suggested by the model and geochemical data was corroborated by minor changes in seismic P-wave velocity measurements and micro-CT imaging; the latter provided direct evidence of sparsely distributed calcium carbonate precipitation. Ion exchange processes promoted through NH{sub 4}{sup

  8. Digital Underground (Shh. It's really Applied Geophysics!)

    Science.gov (United States)

    McAdoo, B. G.

    2003-12-01

    Digital Underground (Geology/Physics 241) at Vassar College is an applied geophysics course designed for a liberal arts curriculum, and has nothing to do with Shock G and Tupac Shakur. Applied geophysics courses have a history of using geophysical methods on environmental contamination-type applications (underground storage tanks, leach fields, etc.). Inspired in large part by the Keck Geology Consortium project run by Franklin and Marshall College geophysicist (Robert Sternberg) and archaeologist (James Delle) in an old slave village in Jamaica in 1999, this class examines the history of slavery in New York's Hudson Valley region by way of its forgotten African-American graveyards. This multidisciplinary approach to an issue draws students from across the curriculum- we have had our compliments of geologists and physicists, along with students from sociology, environmental studies, history, and Africana studies. The name of the class and content are designed to attract a non-traditional student of geophysics.- The project-based nature of the class appeals to student yearning for an out-of-classroom experience. The uncontrolled nature of the class demonstrates the complications that occur in real-word situations. The class has in the past broken itself into two teams- a surveying team and an archival research team. Archival research is done (usually by the social scientists in the class) to add a human dimension to the geophysical. The surveying equipment used in delineating these forgotten graveyards includes a Total Station surveyor, an electrical resistivity meter, a magnetometer, and a ground penetrating radar. All students must have a rudimentary understanding of the physics behind the equipment (to the level of where they can explain it to the general public), and the methods used by those studying the archives. This is a project-based class, where the instructor acts as a project manager, and the students make the decisions regarding the survey itself. Every

  9. Geochemical and isotopic characterization of the ground water of Oued Laya

    International Nuclear Information System (INIS)

    Hkiri, Sabrine

    2010-01-01

    In the Sahel region of Sousse (Tunisia Center East), almost all of the deep groundwater has undergone over the last decade, a general decline of groundwater level. This decrease is caused by two factors, the intensive farming and drought. These aquifers, despite their often poor quality (high salinity), are increasingly used, so they are now home to intense exploitation, whose consequences have emerged as significant declines of groundwater level and degradation of the chemical quality of their water. This study concerns a groundwater aquifer that is under stress and anthropogenic climate severe enough: the coastal aquifer of Wad Laya present quality of groundwater qualified low salinity point of view compared to other neighboring aquifers. The salinity is apparently not related to over exploitation as the majority of coastal aquifers but seems it is due to the geological nature which forms the water table. The region's climate is semiarid with an average annual rainfall of 320 mm by 100 years; the FTE is 1750 mm / year resulting in a water deficit of more than 1.4 m / year. Renewable resources are estimated at 3.3 million m3, while for the levy is estimated to be 2.7 million m3 which the dry residue is currently spent 5g / l (CRDA Sousse, 2009). The objective of this study included hydrogeological characterization of the aquifer using geophysical tools and identification of mechanisms of salination using geochemical and isotopic tools to determine the possible origins of mineralization. For this campaign sampling and measurement was made in the region over a thirty water points in order to measure the electrical conductivity, groundwater level and analyze the chemical composition (major and trace elements). Initial findings from this study are summarized in: Completion of piezometric maps and potentiometric study of the evolution in some wells show a decline of water table caused by the increased exploitation and lower rainfall, which resulted in an increase in

  10. Surface Geophysical Exploration - Compendium Document

    International Nuclear Information System (INIS)

    Rucker, D.F.; Myers, D.A.

    2011-01-01

    This report documents the evolution of the surface geophysical exploration (SGE) program and highlights some of the most recent successes in imaging conductive targets related to past leaks within and around Hanford's tank farms. While it is noted that the SGE program consists of multiple geophysical techniques designed to (1) locate near surface infrastructure that may interfere with (2) subsurface plume mapping, the report will focus primarily on electrical resistivity acquisition and processing for plume mapping. Due to the interferences from the near surface piping network, tanks, fences, wells, etc., the results of the three-dimensional (3D) reconstruction of electrical resistivity was more representative of metal than the high ionic strength plumes. Since the first deployment, the focus of the SGE program has been to acquire and model the best electrical resistivity data that minimizes the influence of buried metal objects. Toward that goal, two significant advances have occurred: (1) using the infrastructure directly in the acquisition campaign and (2) placement of electrodes beneath the infrastructure. The direct use of infrastructure was successfully demonstrated at T farm by using wells as long electrodes (Rucker et al., 2010, 'Electrical-Resistivity Characterization of an Industrial Site Using Long Electrodes'). While the method was capable of finding targets related to past releases, a loss of vertical resolution was the trade-off. The burying of electrodes below the infrastructure helped to increase the vertical resolution, as long as a sufficient number of electrodes are available for the acquisition campaign.

  11. Geophysical characterization of subsurface barriers

    International Nuclear Information System (INIS)

    Borns, D.J.

    1995-08-01

    An option for controlling contaminant migration from plumes and buried waste sites is to construct a subsurface barrier of a low-permeability material. The successful application of subsurface barriers requires processes to verify the emplacement and effectiveness of barrier and to monitor the performance of a barrier after emplacement. Non destructive and remote sensing techniques, such as geophysical methods, are possible technologies to address these needs. The changes in mechanical, hydrologic and chemical properties associated with the emplacement of an engineered barrier will affect geophysical properties such a seismic velocity, electrical conductivity, and dielectric constant. Also, the barrier, once emplaced and interacting with the in situ geologic system, may affect the paths along which electrical current flows in the subsurface. These changes in properties and processes facilitate the detection and monitoring of the barrier. The approaches to characterizing and monitoring engineered barriers can be divided between (1) methods that directly image the barrier using the contrasts in physical properties between the barrier and the host soil or rock and (2) methods that reflect flow processes around or through the barrier. For example, seismic methods that delineate the changes in density and stiffness associated with the barrier represents a direct imaging method. Electrical self potential methods and flow probes based on heat flow methods represent techniques that can delineate the flow path or flow processes around and through a barrier

  12. SURFACE GEOPHYSICAL EXPLORATION - COMPENDIUM DOCUMENT

    Energy Technology Data Exchange (ETDEWEB)

    RUCKER DF; MYERS DA

    2011-10-04

    This report documents the evolution of the surface geophysical exploration (SGE) program and highlights some of the most recent successes in imaging conductive targets related to past leaks within and around Hanford's tank farms. While it is noted that the SGE program consists of multiple geophysical techniques designed to (1) locate near surface infrastructure that may interfere with (2) subsurface plume mapping, the report will focus primarily on electrical resistivity acquisition and processing for plume mapping. Due to the interferences from the near surface piping network, tanks, fences, wells, etc., the results of the three-dimensional (3D) reconstruction of electrical resistivity was more representative of metal than the high ionic strength plumes. Since the first deployment, the focus of the SGE program has been to acquire and model the best electrical resistivity data that minimizes the influence of buried metal objects. Toward that goal, two significant advances have occurred: (1) using the infrastructure directly in the acquisition campaign and (2) placement of electrodes beneath the infrastructure. The direct use of infrastructure was successfully demonstrated at T farm by using wells as long electrodes (Rucker et al., 2010, 'Electrical-Resistivity Characterization of an Industrial Site Using Long Electrodes'). While the method was capable of finding targets related to past releases, a loss of vertical resolution was the trade-off. The burying of electrodes below the infrastructure helped to increase the vertical resolution, as long as a sufficient number of electrodes are available for the acquisition campaign.

  13. Central Colorado Assessment Project (CCAP)-Geochemical data for rock, sediment, soil, and concentrate sample media

    Science.gov (United States)

    Granitto, Matthew; DeWitt, Ed H.; Klein, Terry L.

    2010-01-01

    This database was initiated, designed, and populated to collect and integrate geochemical data from central Colorado in order to facilitate geologic mapping, petrologic studies, mineral resource assessment, definition of geochemical baseline values and statistics, environmental impact assessment, and medical geology. The Microsoft Access database serves as a geochemical data warehouse in support of the Central Colorado Assessment Project (CCAP) and contains data tables describing historical and new quantitative and qualitative geochemical analyses determined by 70 analytical laboratory and field methods for 47,478 rock, sediment, soil, and heavy-mineral concentrate samples. Most samples were collected by U.S. Geological Survey (USGS) personnel and analyzed either in the analytical laboratories of the USGS or by contract with commercial analytical laboratories. These data represent analyses of samples collected as part of various USGS programs and projects. In addition, geochemical data from 7,470 sediment and soil samples collected and analyzed under the Atomic Energy Commission National Uranium Resource Evaluation (NURE) Hydrogeochemical and Stream Sediment Reconnaissance (HSSR) program (henceforth called NURE) have been included in this database. In addition to data from 2,377 samples collected and analyzed under CCAP, this dataset includes archived geochemical data originally entered into the in-house Rock Analysis Storage System (RASS) database (used by the USGS from the mid-1960s through the late 1980s) and the in-house PLUTO database (used by the USGS from the mid-1970s through the mid-1990s). All of these data are maintained in the Oracle-based National Geochemical Database (NGDB). Retrievals from the NGDB and from the NURE database were used to generate most of this dataset. In addition, USGS data that have been excluded previously from the NGDB because the data predate earliest USGS geochemical databases, or were once excluded for programmatic reasons

  14. Geochemical Anomalies in the Sediments of Lake Druksiai

    International Nuclear Information System (INIS)

    Kleinas, A.

    1999-01-01

    In order to evaluate the impact of Ignalina Nuclear Power Plant (NPP) on natural processes in Lake Druksiai and accumulation of pollutants, in 19931997, carrying on the state scientific program, the Marine Geochemistry Division of the Institute of Geography performed lithological geochemical mapping of lake bottom sediments on a scale of 1 .50 000. The results obtained enabled to distinguish zones of higher anthropogenous geochemical load, where geochemical anomalies of pollutants, including oil hydrocarbons and heavy metals, had been taken into account. Applying concentration coefficients for oil hydrocarbons and heavy metals (Cr, Cu, Ni, Pb, and Zn) and their natural background, the attempt was made to differentiate natural and technogenous components in the geochemical anomalies As expected, the finer sediments -aleurite-pelite mud - showed amounts of oil hydrocarbons and heavy metals being 12.1 times higher than in fine sand - the most coarse of the sediments studied Sediments with organic mater exceeding 20% contained 11.7 times more pollutants than those with organic matter below 1 .5%. Calculations of concentration coefficients (CC) showed no elements in no stations exceeded 10 - the sediments did not reach the category of high pollution However, in many sites, the coefficients exceeded values of 1-2, thus, showing sediments attributable to the categories of weakly polluted or just polluted. Mapping model done by GIS methods (by superimposing schemes of pollutant CCs distribution in the lake and summing them) for geochemical anomalies two derivative map-schemes were obtained for oil hydrocarbons and heavy metals. They showed that clean sediments cover just 24.75% (according to the pollutant background for soil types) and 12.35% (according to the organic matter background for its amount intervals) lake bottom area. Zones slightly polluted by an element at least cover 69.7 and 80.29% of lake area, correspondingly; whereas zones slightly polluted by all

  15. Applied Geophysics Opportunities in the Petroleum Industry

    Science.gov (United States)

    Olgaard, D. L.; Tikku, A.; Roberts, J. C.; Martinez, A.

    2012-12-01

    Meeting the increasing global demand for energy over the next several decades presents daunting challenges to engineers and scientists, including geoscientists of all disciplines. Many opportunities exist for geophysicists to find and produce oil and gas in a safe, environmentally responsible and affordable manner. Successful oil and gas exploration involves a 'Plates to Pores' approach that integrates multi-scale data from satellites, marine and land seismic and non-seismic field surveys, lab experiments, and even electron microscopy. The petroleum industry is at the forefront of using high performance computing to develop innovative methods to process and analyze large volumes of seismic data and perform realistic numerical modeling, such as finite element fluid flow and rock deformation simulations. Challenging and rewarding jobs in exploration, production and research exist for students with BS/BA, MS and PhD degrees. Geophysics students interested in careers in the petroleum industry should have a broad foundation in science, math and fundamental geosciences at the BS/BA level, as well as mastery of the scientific method, usually gained through thesis work at MS and PhD levels. Field geology or geophysics experience is also valuable. Other personal attributes typical for geoscientists to be successful in industry include a passion for solving complex geoscience problems, the flexibility to work on a variety of assignments throughout a career and skills such as teamwork, communication, integration and leadership. In this presentation we will give examples of research, exploration and production opportunities for geophysicists in petroleum companies and compare and contrast careers in academia vs. industry.

  16. 3D geophysical inversion for contact surfaces

    Science.gov (United States)

    Lelièvre, Peter; Farquharson, Colin

    2014-05-01

    Geologists' interpretations about the Earth typically involve distinct rock units with contacts (interfaces) between them. In contrast, standard minimum-structure volumetric inversions (performed on meshes of space-filling cells) recover smooth models inconsistent with such interpretations. There are several approaches through which geophysical inversion can help recover models with the desired characteristics. Some authors have developed iterative strategies in which several volumetric inversions are performed with regularization parameters changing to achieve sharper interfaces at automatically determined locations. Another approach is to redesign the regularization to be consistent with the desired model characteristics, e.g. L1-like norms or compactness measures. A few researchers have taken approaches that limit the recovered values to lie within particular ranges, resulting in sharp discontinuities; these include binary inversion, level set methods and clustering strategies. In most of the approaches mentioned above, the model parameterization considers the physical properties in each of the many space-filling cells within the volume of interest. The exception are level set methods, in which a higher dimensional function is parameterized and the contact surface is determined from the zero-level of that function. However, even level-set methods rely on an underlying volumetric mesh. We are researching a fundamentally different type of inversion that parameterizes the Earth in terms of the contact surfaces between rock units. 3D geological Earth models typically comprise wireframe surfaces of tessellated triangles or other polygonal planar facets. This wireframe representation allows for flexible and efficient generation of complicated geological structures. Therefore, a natural approach for representing a geophysical model in an inversion is to parameterize the wireframe contact surfaces as the coordinates of the nodes (facet vertices). The geological and

  17. Geophysical subsurface imaging and interface identification.

    Energy Technology Data Exchange (ETDEWEB)

    Pendley, Kevin; Bochev, Pavel Blagoveston; Day, David Minot; Robinson, Allen Conrad; Weiss, Chester Joseph

    2005-09-01

    Electromagnetic induction is a classic geophysical exploration method designed for subsurface characterization--in particular, sensing the presence of geologic heterogeneities and fluids such as groundwater and hydrocarbons. Several approaches to the computational problems associated with predicting and interpreting electromagnetic phenomena in and around the earth are addressed herein. Publications resulting from the project include [31]. To obtain accurate and physically meaningful numerical simulations of natural phenomena, computational algorithms should operate in discrete settings that reflect the structure of governing mathematical models. In section 2, the extension of algebraic multigrid methods for the time domain eddy current equations to the frequency domain problem is discussed. Software was developed and is available in Trilinos ML package. In section 3 we consider finite element approximations of De Rham's complex. We describe how to develop a family of finite element spaces that forms an exact sequence on hexahedral grids. The ensuing family of non-affine finite elements is called a van Welij complex, after the work [37] of van Welij who first proposed a general method for developing tangentially and normally continuous vector fields on hexahedral elements. The use of this complex is illustrated for the eddy current equations and a conservation law problem. Software was developed and is available in the Ptenos finite element package. The more popular methods of geophysical inversion seek solutions to an unconstrained optimization problem by imposing stabilizing constraints in the form of smoothing operators on some enormous set of model parameters (i.e. ''over-parametrize and regularize''). In contrast we investigate an alternative approach whereby sharp jumps in material properties are preserved in the solution by choosing as model parameters a modest set of variables which describe an interface between adjacent regions in

  18. LASL approach to uranium geochemical reconnaissance

    Energy Technology Data Exchange (ETDEWEB)

    Sharp, R.R. Jr.

    1977-01-01

    The US ERDA, as part of the NURE program, has initiated a nationwide Hydrogeochemical and Stream Sediment Reconnaissance (HSSR). The aims of the NURE program are to provide data on which to base more accurate estimates of US uranium reserves for long-range planning and to aid in meeting the nation's projected uranium demands into the next century. The HSSR objective is to complete, by 1980, a reconnaissance of the nation's surface waters, ground waters, and stream and lake sediments, to aid in assessment of uranium reserves and identification of areas of interest for exploration. Patterned after extensive uranium reconnaissance done in many other countries, the LASL project is comprised of the following five components: (1) organization and planning, which includes management, design, and execution; (2) field sampling, which includes orientation studies, generation of specifications, and contracting and inspection of field work; (3) sample receiving and analysis, which includes development of methods and hardware, quality assurance, and archival storage; (4) data handling and presentation, including verification, storage, output, and plotting; and (5) data evaluation and publication, which incorporates geochemical, geological, statistical, and empirical evaluation and report writing. The LASL approach to each component and the current status in each state are described.

  19. LASL approach to uranium geochemical reconnaissance

    International Nuclear Information System (INIS)

    Sharp, R.R. Jr.

    1977-01-01

    The US ERDA, as part of the NURE program, has initiated a nationwide Hydrogeochemical and Stream Sediment Reconnaissance (HSSR). The aims of the NURE program are to provide data on which to base more accurate estimates of US uranium reserves for long-range planning and to aid in meeting the nation's projected uranium demands into the next century. The HSSR objective is to complete, by 1980, a reconnaissance of the nation's surface waters, ground waters, and stream and lake sediments, to aid in assessment of uranium reserves and identification of areas of interest for exploration. Patterned after extensive uranium reconnaissance done in many other countries, the LASL project is comprised of the following five components: (1) organization and planning, which includes management, design, and execution; (2) field sampling, which includes orientation studies, generation of specifications, and contracting and inspection of field work; (3) sample receiving and analysis, which includes development of methods and hardware, quality assurance, and archival storage; (4) data handling and presentation, including verification, storage, output, and plotting; and (5) data evaluation and publication, which incorporates geochemical, geological, statistical, and empirical evaluation and report writing. The LASL approach to each component and the current status in each state are described

  20. Geochemical criteria for reservoir quality variations in chalk from the North Sea

    International Nuclear Information System (INIS)

    Kunzendorf, H.; Soerensen, P.

    1989-12-01

    The influence of chalk geochemistry on petrophysical parameters determining porosity and permeability is investigated. The central well TWB-8 and eastern marginal well E-lx of the North Sea Tyra gas field were chosen. Drill core sections of Upper Maastrichtian and Danian chalk were selected. Chemical data on chalk samples were gathered by using X-ray fluorescence and instrumental neutron activation. Geochemical data are compared with the well-logging results. Geophysical logging suggests that there is reduced porosity in the Danian reservoir units LDP and UDT in both wells. The chalk drill core samples from the section with reduced porosity also show a lower Ca content. A high Si content is observed in these samples and a number of trace elements in chalk show a similar distribution with depth. Reservoir porosity may be estimated from the Si content of chalk. Chalk permeability may also be elements Al, Fe and Sc show the same trends as that for Si. Diagenetic changes in chalk also include clay minerals. The gas zone in TWB-8 is characterized by low contents of Na and Cl, i.e. lower water saturation is indicated. Low concentrations of rare earths in all chalk samples show a shale-normalized pattern that is characteristic of marine sediments laid down under oxic conditions. Some changes that occur with depth in the Ce anomaly may indicate a slight change in the depositional environment. The content of manganese continuously decreases with depth, from Danian (about 2000 ppm) to Maastrichtian strata (less than 200 ppm). In this respect, no other chemical element in chalk correlates with Mn. There is no indication as to which mineral or mineral phase one is likely to find in the element. (AB) 14 tabs., 49 ills., 147 refs

  1. History of geophysical studies at the Waste Isolation Pilot Plant (WIPP), southeastern New Mexico

    International Nuclear Information System (INIS)

    Borns, D.J.

    1997-01-01

    A variety of geophysical methods including the spectrum of seismic, electrical, electromagnetic and potential field techniques have used support characterization, monitoring and experimental studies at the Waste Isolation Pilot Plant (WIPP). The geophysical studies have provided significant understanding of the nature of site deformation, tectonics and stability. Geophysical methods have delineated possible brine reservoirs beneath the underground facility and have defined the disturbed rock zone that forms around underground excavations. The role of geophysics in the WIPP project has evolved with the project. The early uses were for site characterization to satisfy site selection criteria or factors. As the regulatory framework for WIPP grew since 1980, the geophysics program was focused on support of experimental and field programs such as Salado hydrogeology and underground room systems and excavations. In summary, the major types of issues that geophysical studies addressed for WIPP are: Issue 1: Site Characterization; Issue 2: Castile Brine Reservoirs; Issue 3: Rustler /Dewey Lake Hydrogeology; Issue 4: Salado Hydrogeology; and Issue 5: Excavation Effects. The nature of geophysics program for WIPP has been to support investigation rather than being the principal investigation itself. The geophysics program has been used to define conceptual models (e.g., the Disturbed Rock Zone-DRZ) or to test conceptual models (e.g., high transmissivity zones in the Rustler Formation). An effect of being a support program is that as new project priorities arose the funding for the geophysics program was limited and withdrawn. An outcome is that much of the geophysics survey information resides in contractor reports since final interpretation reports were not funded

  2. Potential application of radiogenic isotopes and geophysical methods to understand the hydrothermal dystem of the Upper Geyser Basin, Yellowstone National Park

    Science.gov (United States)

    Paces, James B.; Long, Andrew J.; Koth, Karl R.

    2015-01-01

    Numerous geochemical and geophysical studies have been conducted at Yellowstone National Park to better understand the hydrogeologic processes supporting the thermal features of the Park. This report provides the first 87Sr/86Sr and 234U/238U data for thermal water from the Upper Geyser Basin (UGB) intended to evaluate whether heavy radiogenic isotopes might provide insight to sources of groundwater supply and how they interact over time and space. In addition, this report summarizes previous geophysical studies made at Yellowstone National Park and provides suggestions for applying non-invasive ground and airborne studies to better understand groundwater flow in the subsurface of the UGB. Multiple samples from Old Faithful, Aurum, Grand, Oblong, and Daisy geysers characterized previously for major-ion concentrations and isotopes of water (δ2H, δ18O, and 3H) were analyzed for Sr and U isotopes. Concentrations of dissolved Sr and U are low (4.3–128 ng g-1 Sr and 0.026–0.0008 ng g-1 U); consequently only 87Sr/86Sr data are reported for most samples. Values of 87Sr/86Sr for most geysers remained uniform between April and September 2007, but show large increases in all five geysers between late October 2007 and early April, 2008. By late summer of 2008, 87Sr/86Sr values returned to values similar to those observed a year earlier. Similar patterns are not present in major-ion data measured on the same samples. Furthermore, large geochemical differences documented between geysers are not observed in 87Sr/86Sr data, although smaller differences between sites may be present. Sr-isotope data are consistent with a stratified hydrologic system where water erupted in spring and summer of 2007 and summer of 2008 equilibrated with local intracaldera rhyolite flows at shallower depths. Water erupted between October 2007 and April 2008 includes greater amounts of groundwater that circulated deep enough to acquire a radiogenic 87Sr/86Sr, most likely from Archean basement

  3. Geodetic and geophysical observations in Antarctica an overview in the IPY perspective

    CERN Document Server

    Capra, Alessandro

    2008-01-01

    This book is a collection of papers on various aspects of the geodetic and geophysical investigation and observation techniques. It includes material from the Arctic and Antarctica, as well as covering work from both temporary and permanent observatories.

  4. Adobe Illustrator drawing showing geophysical and topographical survey data and interpretations

    OpenAIRE

    Wallace, Lacey; Ferraby, Rose

    2016-01-01

    Adobe Illustrator drawing at 1:2000 that shows the rasters and interpretations of the geophysics, the topographical contours, and the survey areas, with British National Grid coordinates and Ordnance Survey Master Map data included.

  5. Numerical simulation in applied geophysics

    CERN Document Server

    Santos, Juan Enrique

    2016-01-01

    This book presents the theory of waves propagation in a fluid-saturated porous medium (a Biot medium) and its application in Applied Geophysics. In particular, a derivation of absorbing boundary conditions in viscoelastic and poroelastic media is presented, which later is employed in the applications. The partial differential equations describing the propagation of waves in Biot media are solved using the Finite Element Method (FEM). Waves propagating in a Biot medium suffer attenuation and dispersion effects. In particular the fast compressional and shear waves are converted to slow diffusion-type waves at mesoscopic-scale heterogeneities (on the order of centimeters), effect usually occurring in the seismic range of frequencies. In some cases, a Biot medium presents a dense set of fractures oriented in preference directions. When the average distance between fractures is much smaller than the wavelengths of the travelling fast compressional and shear waves, the medium behaves as an effective viscoelastic an...

  6. Geochemical Consequences of Lithospheric Delamination in the Eastern Mediterranean: Evidence From Young Turkish Basalts

    Science.gov (United States)

    Furman, T.; Kurkcuoglu, B.; Plummer, C.

    2007-12-01

    Magmatism associated with continental collision is increasingly attributed to major disturbance of or within the lithosphere. Geochemical and isotopic data on post-collisional primitive mafic lavas from across the Anatolian plate enable us to assess the effects of lithospheric delamination (slab rollback and breakoff) as indicated by geophysical studies. The Anatolian province displays geodynamically complex manifestations of the closure of neo-Tethys and the collision between Africa and Europe that commenced circa 30 Ma. The current south- southwestward motion of Anatolia, a.k.a. "Turkish escape", is accommodated by slab rollback along the Hellenic trench and orogenic collapse along both the eastern and western margins of the microplate. Volcanism occurs primarily along the fault zones that border and cross-cut Anatolia, and major element characteristics of the lavas vary with both space and time. In Western Anatolia, early Miocene collisional calc- alkaline magmatism was followed by Quaternary alkaline volcanism (Alici et al. 1998, 2002; Aldanmaz et al. 2000, 2006) related to orogenic collapse, presumably resulting from slab rollback. Orogenic collapse in Eastern Anatolia is facilitated by slab breakoff as determined by geophysical studies (Zor et al. 2003; Angus et al. 2006; Lei & Zhao 2007). This transition was accompanied a change from mid-Miocene calc-alkaline to Quaternary alkaline volcanism (e.g., Yilmaz 1990; Pearce et al. 1990). Central Anatolia displays calc-alkaline and tholeiitic volcanism, including alkali olivine basalts; plate tectonic reconstructions (Lyberis et al. 1992) indicate that the African slab did not reach Central Anatolia. Sr-Nd isotope values from each volcanic province define linear arrays that converge upon a common unradiogenic value typical of global depleted mantle. We suggest that mafic volcanism throughout Anatolia is supported by a common asthenospheric component, modified by identifiable, location-specific additions. In areas

  7. Compiling Data from Geological, Mineralogical and Geophysical (IP/RS Studies on Mahour Deposit, Northwest of Deh-salm, Lut Block

    Directory of Open Access Journals (Sweden)

    Arash Gorabjeiri Puor

    2015-10-01

    Full Text Available Introduction The Mahour exploration area is a polymetallic system containing copper, zinc and silver. The mineralization can be seen in two forms of veins and disseminations. This area is structurally within the Lut block, west of Deh-salm Village. Recent exploration work and studies carried out by geologists on this volcanic-plutonic area of Lut demonstate its importance indicating new reserves of copper, gold, and lead and zinc. Several articles have been published on the Mahour deposit in recent years, including work on fluid inclusions (Mirzaei et al., 2012a; Mirzaei et al., 2012b. The present report aims at completion of previous studies on Mahour. During the course of this research, the IP/RS geophysical methods were used to locate the extent and depth of sulfide veins in order to locate drill sites. The IP/RS method has been used extensively worldwide in locating sulfide mineralization at deposits such as Olympic Dam in Australia (Esdale et al., 1987, Hishikari epithermal gold deposit in Kagoshima, Japan (Okada, 1995 and Cadia-Ridgeway copper and gold deposit in New South Wales, Australia (Rutley et al., 2001. Materials and Methods 1. Determination of mineralogy of ore and alteration by examination of 70 thin sections and 45 polished sections. 2. Compilation of geological and mineralization maps of the studied area at a scale of 1:1000. 3. Geological, alteration, mineralization and trace element geochemical studies of 6 drill holes. 4. IP/RS measurements for 2585 points on a rectangular grid with profile intervals of 50 meters and electrode intervals of 20 meters. 5. Interpretation of IP/RS results. Discussion The Mahour area is covered by a volcanic sequence of basalt, andesite, dacite, rhyolite and pyro-clastics. During the Late Eocene through Early Oligocene this volcanic complex was intruded by several diorite and quartz-diorite bodies, which were responsible for mineralization of the area. Mineralized veins hosted by dacite show NNE

  8. Coupling of transport and geochemical models

    International Nuclear Information System (INIS)

    Noy, D.J.

    1986-01-01

    This report considers mass transport in the far-field of a radioactive waste repository, and detailed geochemical modelling of the ground-water in the near-field. A parallel approach to this problem of coupling transport and geochemical codes is the subject of another CEC report (ref. EUR 10226). Both studies were carried out in the framework of the CEC project MIRAGE. (Migration of radionuclides in the geosphere)

  9. Geophysical Methods for Investigating Ground-Water Recharge

    Science.gov (United States)

    Ferre, Ty P.A.; Binley, Andrew M.; Blasch, Kyle W.; Callegary, James B.; Crawford, Steven M.; Fink, James B.; Flint, Alan L.; Flint, Lorraine E.; Hoffmann, John P.; Izbicki, John A.; Levitt, Marc T.; Pool, Donald R.; Scanlon, Bridget R.

    2007-01-01

    that are currently available or under development for recharge monitoring. The material is written primarily for hydrogeologists. Uses of geophysical methods for improving recharge monitoring are explored through brief discussions and case studies. The intent is to indicate how geophysical methods can be used effectively in studying recharge processes and quantifying recharge. As such, the material constructs a framework for matching the strengths of individual geophysical methods with the manners in which they can be applied for hydrologic analyses. The appendix is organized in three sections. First, the key hydrologic parameters necessary to determine the rate, timing, and patterns of recharge are identified. Second, the basic operating principals of the relevant geophysical methods are discussed. Methods are grouped by the physical property that they measure directly. Each measured property is related to one or more of the key hydrologic properties for recharge monitoring. Third, the emerging conceptual framework for applying geophysics to recharge monitoring is presented. Examples of the application of selected geophysical methods to recharge monitoring are presented in nine case studies. These studies illustrate hydrogeophysical applications under a wide range of conditions and measurement scales, which vary from tenths of a meter to hundreds of meters. The case studies include practice-proven as well as emerging applications of geophysical methods to recharge monitoring.

  10. Stream-sediment geochemical exploration for uranium in Narigan area Central Iran

    International Nuclear Information System (INIS)

    Yazdi, M.; Khoshnoodi, K.; Kavand, M.; Ashteyani, A. R.

    2009-01-01

    Uranium deposits of Iran occur mainly in the Central Iran zone. Several uranium deposits have been discovered in this zone. The Narigan area is one of the most important uranium mineralized area in this zone. The uranium bearing sequences in this area are contained in the plutonic to volcanic rocks of Narigan which intruded to the Pre-Cambrian pyroclastics rocks. Plutonic and volcanic rocks are granite, rhyolite and volcanoclastic. Diabasic dykes have been intruded to these igneous rocks. The plutonic and volcanic rocks have been covered by Cretaceous limestones which seem to be youngest the rocks in this area. The aim of our project is to develop a regional exploration strategy for uranium in these igneous rocks. A grid-based sampling was planned following the results of the previous geochemical mapping at a scale of 1:100,000, integrated with geophysical data and alteration zones and outcrop of intrusive rocks. The following results are based on geological, and stream geochemical explorations in 1:20000 scale of this area. During this study 121 samples were collected from the stream sediments of <80 mesh for final sampling. Ten percent of the samples were used for checking laboratories errors. The samples were collected according to conventional methods from 30-40 cm depth of stream sediments. Finally, geochemical and radiometric data were combined and the results introduced 3 anomalies in the Narigan area

  11. Mineral and Geochemical Classification From Spectroscopy/Diffraction Through Neural Networks

    Science.gov (United States)

    Ferralis, N.; Grossman, J.; Summons, R. E.

    2017-12-01

    Spectroscopy and diffraction techniques are essential for understanding structural, chemical and functional properties of geological materials for Earth and Planetary Sciences. Beyond data collection, quantitative insight relies on experimentally assembled, or computationally derived spectra. Inference on the geochemical or geophysical properties (such as crystallographic order, chemical functionality, elemental composition, etc.) of a particular geological material (mineral, organic matter, etc.) is based on fitting unknown spectra and comparing the fit with consolidated databases. The complexity of fitting highly convoluted spectra, often limits the ability to infer geochemical characteristics, and limits the throughput for extensive datasets. With the emergence of heuristic approaches to pattern recognitions though machine learning, in this work we investigate the possibility and potential of using supervised neural networks trained on available public spectroscopic database to directly infer geochemical parameters from unknown spectra. Using Raman, infrared spectroscopy and powder x-ray diffraction from the publicly available RRUFF database, we train neural network models to classify mineral and organic compounds (pure or mixtures) based on crystallographic structure from diffraction, chemical functionality, elemental composition and bonding from spectroscopy. As expected, the accuracy of the inference is strongly dependent on the quality and extent of the training data. We will identify a series of requirements and guidelines for the training dataset needed to achieve consistent high accuracy inference, along with methods to compensate for limited of data.

  12. Version 4. 00 of the MINTEQ geochemical code

    Energy Technology Data Exchange (ETDEWEB)

    Eary, L.E.; Jenne, E.A.

    1992-09-01

    The MINTEQ code is a thermodynamic model that can be used to calculate solution equilibria for geochemical applications. Included in the MINTEQ code are formulations for ionic speciation, ion exchange, adsorption, solubility, redox, gas-phase equilibria, and the dissolution of finite amounts of specified solids. Since the initial development of the MINTEQ geochemical code, a number of undocumented versions of the source code and data files have come into use at the Pacific Northwest Laboratory (PNL). This report documents these changes, describes source code modifications made for the Aquifer Thermal Energy Storage (ATES) program, and provides comprehensive listings of the data files. A version number of 4.00 has been assigned to the MINTEQ source code and the individual data files described in this report.

  13. Version 4.00 of the MINTEQ geochemical code

    Energy Technology Data Exchange (ETDEWEB)

    Eary, L.E.; Jenne, E.A.

    1992-09-01

    The MINTEQ code is a thermodynamic model that can be used to calculate solution equilibria for geochemical applications. Included in the MINTEQ code are formulations for ionic speciation, ion exchange, adsorption, solubility, redox, gas-phase equilibria, and the dissolution of finite amounts of specified solids. Since the initial development of the MINTEQ geochemical code, a number of undocumented versions of the source code and data files have come into use at the Pacific Northwest Laboratory (PNL). This report documents these changes, describes source code modifications made for the Aquifer Thermal Energy Storage (ATES) program, and provides comprehensive listings of the data files. A version number of 4.00 has been assigned to the MINTEQ source code and the individual data files described in this report.

  14. Geochemical reanalysis of historical U.S. Geological Survey sediment samples from the Inmachuk, Kugruk, Kiwalik, and Koyuk River drainages, Granite Mountain, and the northern Darby Mountains, Bendeleben, Candle, Kotzebue, and Solomon quadrangles, Alaska

    Science.gov (United States)

    Werdon, Melanie B.; Granitto, Matthew; Azain, Jaime S.

    2015-01-01

    The State of Alaska’s Strategic and Critical Minerals (SCM) Assessment project, a State-funded Capital Improvement Project (CIP), is designed to evaluate Alaska’s statewide potential for SCM resources. The SCM Assessment is being implemented by the Alaska Division of Geological & Geophysical Surveys (DGGS), and involves obtaining new airborne-geophysical, geological, and geochemical data. As part of the SCM Assessment, thousands of historical geochemical samples from DGGS, U.S. Geological Survey (USGS), and U.S. Bureau of Mines archives are being reanalyzed by DGGS using modern, quantitative, geochemical-analytical methods. The objective is to update the statewide geochemical database to more clearly identify areas in Alaska with SCM potential. The USGS is also undertaking SCM-related geologic studies in Alaska through the federally funded Alaska Critical Minerals cooperative project. DGGS and USGS share the goal of evaluating Alaska’s strategic and critical minerals potential and together created a Letter of Agreement (signed December 2012) and a supplementary Technical Assistance Agreement (#14CMTAA143458) to facilitate the two agencies’ cooperative work. Under these agreements, DGGS contracted the USGS in Denver to reanalyze historical USGS sediment samples from Alaska. For this report, DGGS funded reanalysis of 653 historical USGS sediment samples from the statewide Alaska Geochemical Database Version 2.0 (AGDB2; Granitto and others, 2013). Samples were chosen from an area covering portions of the Inmachuk, Kugruk, Kiwalik, and Koyuk river drainages, Granite Mountain, and the northern Darby Mountains, located in the Bendeleben, Candle, Kotzebue, and Solomon quadrangles of eastern Seward Peninsula, Alaska (fig. 1). The USGS was responsible for sample retrieval from the National Geochemical Sample Archive (NGSA) in Denver, Colorado through the final quality assurance/quality control (QA/QC) of the geochemical analyses obtained through the USGS contract

  15. Calibration and Confirmation in Geophysical Models

    Science.gov (United States)

    Werndl, Charlotte

    2016-04-01

    For policy decisions the best geophysical models are needed. To evaluate geophysical models, it is essential that the best available methods for confirmation are used. A hotly debated issue on confirmation in climate science (as well as in philosophy) is the requirement of use-novelty (i.e. that data can only confirm models if they have not already been used before. This talk investigates the issue of use-novelty and double-counting for geophysical models. We will see that the conclusions depend on the framework of confirmation and that it is not clear that use-novelty is a valid requirement and that double-counting is illegitimate.

  16. Site investigation - equipment for geological, geophysical, hydrogeological and hydrochemical characterization

    International Nuclear Information System (INIS)

    Almen, K.E.; Fridh, B.; Johansson, B.E.; Sehlstedt, M.

    1986-11-01

    The investigations are performed within a site investigation program. In total about 60,000 m of cored 56 mm boreholes have been drilled and investigated at eight study sites. A summarized description of the main investigation methods is included. Instruments for geophysical investigations contains equipment for ground measurements as well as for borehole logging. The Geophysical investigations including the borehole radar measurements, are indirect methods for the geological and hydrogeological characterization of the rock formation. Great effort has been laid on the development of hydrogeological instruments for hydraulic tests and groundwater head measurements. In order to obtain hydrochemical investigations with high quality, a complete system for sampling and analysis of ground water has been developed. (orig./PW)

  17. Is there a geochemical link between volcanic and plutonic rocks in the Organ Mountains caldera?

    Science.gov (United States)

    Memeti, V.; Davidson, J.

    2013-12-01

    determine within-crystal geochemical variations. Our current conclusions and working hypotheses are: 1) All igneous rocks from the Organ Mountains are crustal-mantle melt mixtures indicating two component mixing; 2) the caldera-forming ignimbrites are likely derived from a fractionating Organ Needle pluton; 3) pre- and post-caldera lavas are isotopically similar to the post-caldera Sugarloaf Peak quartz-monzonite; 4) K-feldspar cumulate textures in the structurally top 0.5-1 km of the Organ Needle pluton indicate that interstitial melt was lost from the magma mush, which likely fed the ignimbrite eruptions. 5) Plutonic feldspar textures are complex compared to rather simple zoned volcanic feldspars including K-feldspar rimmed plagioclase, plagioclase rimmed K-feldspar and unrimmed feldspars occurring over a range of grain sizes at thin section scale. Some volcanic feldspar phenocrysts have any previous zonation erased due to late stage albitization. Although the single mineral studies are still work in progress and details need resolving, our data so far suggest a geochemical link between volcanic and plutonic rocks of the Organ Mountains caldera, albeit a complex one; and greater complexity in plutonic versus volcanic minerals. [1] Seager (1980), NM Bureau of Mines and Min. Res. Memoir 36, 97 p. [2] Zimmerer & McIntosh (2013) Journal of Geophysical Research, v. 93, p. 4421-4433

  18. Geophysical investigations in the 100 Areas: Fiscal year 1991 through December 1993

    Science.gov (United States)

    Mitchell, T. H.

    1994-09-01

    The geophysical investigations identified in this document were conducted by the Westinghouse Hanford Company (WHC) Surface Geophysics Team, Geophysics Group, between October, 1991 and December, 1993. The investigations supported 100-Area activities for the Resource Conservation and Recovery Act of 1976 (RCRA) and the Comprehensive Environmental Response, Compensations and Liability Act of 1980 (CERCLA). The primary intent of this document is to provide a general map location and the associated document number for investigations that have been conducted as of December, 1993. The results of the individual investigations are not included here. The results of all of these investigations have been previously reported individually in WHC supporting documents. The investigations conducted during Fiscal Year (FY) 1992 are summarized in a single WHC document, WHC-SD-EN-TI-204, Rev. O. A brief summary of some of the successful applications of geophysics in the 100-Areas is included.

  19. Time-Lapse Electrical Geophysical Monitoring of Amendment-Based Biostimulation.

    Science.gov (United States)

    Johnson, Timothy C; Versteeg, Roelof J; Day-Lewis, Frederick D; Major, William; Lane, John W

    2015-01-01

    Biostimulation is increasingly used to accelerate microbial remediation of recalcitrant groundwater contaminants. Effective application of biostimulation requires successful emplacement of amendment in the contaminant target zone. Verification of remediation performance requires postemplacement assessment and contaminant monitoring. Sampling-based approaches are expensive and provide low-density spatial and temporal information. Time-lapse electrical resistivity tomography (ERT) is an effective geophysical method for determining temporal changes in subsurface electrical conductivity. Because remedial amendments and biostimulation-related biogeochemical processes often change subsurface electrical conductivity, ERT can complement and enhance sampling-based approaches for assessing emplacement and monitoring biostimulation-based remediation. Field studies demonstrating the ability of time-lapse ERT to monitor amendment emplacement and behavior were performed during a biostimulation remediation effort conducted at the Department of Defense Reutilization and Marketing Office (DRMO) Yard, in Brandywine, Maryland, United States. Geochemical fluid sampling was used to calibrate a petrophysical relation in order to predict groundwater indicators of amendment distribution. The petrophysical relations were field validated by comparing predictions to sequestered fluid sample results, thus demonstrating the potential of electrical geophysics for quantitative assessment of amendment-related geochemical properties. Crosshole radar zero-offset profile and borehole geophysical logging were also performed to augment the data set and validate interpretation. In addition to delineating amendment transport in the first 10 months after emplacement, the time-lapse ERT results show later changes in bulk electrical properties interpreted as mineral precipitation. Results support the use of more cost-effective surface-based ERT in conjunction with limited field sampling to improve spatial

  20. Time-lapse electrical geophysical monitoring of amendment-based biostimulation

    Science.gov (United States)

    Johnson, Timothy C.; Versteeg, Roelof J.; Day-Lewis, Frederick D.; Major, William; Lane, John W.

    2015-01-01

    Biostimulation is increasingly used to accelerate microbial remediation of recalcitrant groundwater contaminants. Effective application of biostimulation requires successful emplacement of amendment in the contaminant target zone. Verification of remediation performance requires postemplacement assessment and contaminant monitoring. Sampling-based approaches are expensive and provide low-density spatial and temporal information. Time-lapse electrical resistivity tomography (ERT) is an effective geophysical method for determining temporal changes in subsurface electrical conductivity. Because remedial amendments and biostimulation-related biogeochemical processes often change subsurface electrical conductivity, ERT can complement and enhance sampling-based approaches for assessing emplacement and monitoring biostimulation-based remediation.Field studies demonstrating the ability of time-lapse ERT to monitor amendment emplacement and behavior were performed during a biostimulation remediation effort conducted at the Department of Defense Reutilization and Marketing Office (DRMO) Yard, in Brandywine, Maryland, United States. Geochemical fluid sampling was used to calibrate a petrophysical relation in order to predict groundwater indicators of amendment distribution. The petrophysical relations were field validated by comparing predictions to sequestered fluid sample results, thus demonstrating the potential of electrical geophysics for quantitative assessment of amendment-related geochemical properties. Crosshole radar zero-offset profile and borehole geophysical logging were also performed to augment the data set and validate interpretation.In addition to delineating amendment transport in the first 10 months after emplacement, the time-lapse ERT results show later changes in bulk electrical properties interpreted as mineral precipitation. Results support the use of more cost-effective surface-based ERT in conjunction with limited field sampling to improve spatial

  1. 30 CFR 251.12 - Submission, inspection, and selection of geophysical data and information collected under a...

    Science.gov (United States)

    2010-07-01

    ... information, and interpreted geophysical information including, but not limited to, shallow and deep subbottom...) You must notify the Regional Director, in writing, when you complete the initial processing and interpretation of any geophysical data and information. Initial processing is the stage of processing where the...

  2. Role of geochemical background at evaluation of investment attractiveness of recreational territories

    Directory of Open Access Journals (Sweden)

    Vdovina Ol'ga Konstantinovna

    2014-09-01

    Full Text Available The article shows the role of natural geochemical background when estimating investment attractiveness of recreational areas. It is noted, that geochemical background influence on people's sickness rate isn't considered now. Though it's understood, that even insignificant increase of geochemical background in relation to percentage abundance of Earth crest may lead to endemic diseases of people, animals and plants. An indicator of geochemical endemicity areas was proposed for assessing the impact of storage elements and of a lack of geological environment on human health. Thanks to this measure, and taking into account landscape features of the area, the authors allocated lands, dangerous and potentially dangerous in terms of endemicity. The importance of ratings was achieved by the use of those factors that could have a great influence on the cost of land development. This includes, first of all, the factors that affect population health, and economic and geographic factors that minimize the cost of the territory development and the factors that give rise to financial risks and risks of human losses. The main risk factors include: potential ecological and geochemical risk; high absolute heights, development and activity of dangerous geological processes and phenomena. Systemacity of researches was reached by using factors, that characterize the object from different aspects; readiness of area infrastructure to its exploration and possible risks. Objectivity was achieved by the use of figures obtained from the results of geochemical and engineering surveys with their metrological support.

  3. Geochemical behavior of disposed radioactive waste

    International Nuclear Information System (INIS)

    Barney, G.S.; Navratil, J.D.; Schulz, W.W.

    1984-01-01

    The papers in this book are organized to cover the chemical aspects that are important to understanding the behavior of disposed radioactive wastes. These aspects include radionuclide sorption and desorption, solubility of radionuclide compounds, chemical species of radionuclides in natural waters, hydrothermal geochemical reactions, measurements of radionuclide migration, solid state chemistry of wastes, and waste-form leaching behavior. The information in each of the papers is necessary to predict the transport of radionuclides from wastes via natural waters and thus to predict the safety of the disposed waste. Radionuclide transport in natural waters is strongly dependent on sorption, desorption, dissolution, and precipitation processes. The first two papers discuss laboratory investigations of these processes. Descriptions of sorption and desorption behavior of important radionuclides under a wide range of environmental conditions are presented in the first section. Among the sorbents studied are basalt interbed solids, granites, clays, sediments, hydrous oxides, and pure minerals. Effects of redox conditions, groundwater composition and pH on sorption reactions are described

  4. Regional geochemical baselines for Portuguese shelf sediments

    International Nuclear Information System (INIS)

    Mil-Homens, M.; Stevens, R.L.; Cato, I.; Abrantes, F.

    2007-01-01

    Metal concentrations (Al, Cr, Cu, Ni, Pb and Zn) from the DGM-INETI archive data set have been examined for sediments collected during the 1970s from 267 sites on the Portuguese shelf. Due to the differences in the oceanographic and sedimentological settings between western and Algarve coasts, the archive data set is split in two segments. For both shelf segments, regional geochemical baselines (RGB) are defined using aluminium as a reference element. Seabed samples recovered in 2002 from four distinct areas of the Portuguese shelf are superimposed on these models to identify and compare possible metal enrichments relative to the natural distribution. Metal enrichments associated with anthropogenic influences are identified in three samples collected nearby the Tejo River and are characterised by the highest enrichment factors (EF; EF Pb Zn < 4). EF values close to 1 suggest a largely natural origin for metal distributions in sediments from the other areas included in the study. - Background metal concentrations and their natural variability must be established before assessing anthropogenic impacts

  5. A tool for Exploring Geophysical Data: The VGEE-IDV

    Science.gov (United States)

    Pandya, R. E.; Murray, D.

    2002-12-01

    The Visual Geophysical Exploration Environment (VGEE) is a suite of computer tools and accompanying online curricular units that enable students to develop physical insight from geophysical data sets. The VGEE curriculum is inquiry and visualization based. The curriculum begins by asking students to compare visualizations they construct from authentic geosciences data to their own conception of the geophysical phenomenon. This comparison encourages students to identify and challenge their own prior conceptions of the phenomenon, a necessary prerequisite to successful learning. Students then begin building correct understandings by identifying patterns and relationships within their visualizations. Students use idealized concept models that highlight physical principles to explain these patterns and relationships. Research, however, has shown that the physical insight gained from these idealized models isn't often applied to either the real world or to the data visualized. To address this, students can easily embed these idealized concept models into their visualizations; there the idealized models respond to the real physical conditions of the geophysical data. The entire inquiry process is built around multi-dimensional and multi-variable visualizations of real geophysical data. Advantages of visualization include its using a natural human talent and its removing mathematics as a barrier to insight. Multi-dimensional and multi-variable visualizations offer the additional advantage of integrated perspectives; rather than asking learners to mentally combine two-dimensional representations of different variables, the learners can navigate through a three-dimensional time-varying representation and get a holistic view. Finally, learner constructed visualizations offer the students a experience with scientific tools, a chance to tailor their investigation to their own misconceptions, and the potential for more robust understanding than prepared visualizations. The

  6. Airborne geophysical radon hazard mapping

    International Nuclear Information System (INIS)

    Walker, P.

    1993-01-01

    Shales containing uranium pose a radon health hazard even when covered by several meters of overburden. Such an alum shale in southern Norway has been mapped with a joint helicopter borne electromagnetic (HEM) and radiometric survey. Results are compared with ground spectrometer, radon emanometer and radon gas measurements in dwellings, and a model to predict radon gas concentrations from the airborne data is developed. Since the shale is conductive, combining the HEM data with the radiometric channel allows the shale to be mapped with greater reliability than if the radiometric channel were used alone. Radiometrically more active areas which do not pose a radon gas hazard can thus be separated from the shales which do. The ground follow-up work consisted of spectrometer and radon emanometer measurements over a uranium anomaly coinciding with a conductor. The correlation between the airborne uranium channel, the ground uranium channel and emanometry is extremely good, indicating that airborne geophysics can, in this case, be used to predict areas having a high radon potential. Contingency tables comparing both radon exhalation and concentration in dwellings with the airborne uranium data show a strong relationship exists between exhalation and the airborne data and while a relationship between concentration and the airborne data is present, but weaker

  7. Baseline geophysical data for hazard management in coastal areas in relation to earthquakes and tsunamis

    Digital Repository Service at National Institute of Oceanography (India)

    Murthy, K.S.R.

    is another factor for some of the intraplate earthquakes in the South Indian Shield, which includes the Eastern and Western Continental Margins of India. Baseline geophysical data for hazard management in coastal areas in relation to earthquakes... surge. Keywords Hazard management, marine geophysical data, geomorphology and tsunami surge, coastal seismicity Date received: 7 August 2015; accepted: 15 October 2015 CSIR – National Institute of Oceanography, Visakhapatnam, India Corresponding author...

  8. Tabletop Models for Electrical and Electromagnetic Geophysics.

    Science.gov (United States)

    Young, Charles T.

    2002-01-01

    Details the use of tabletop models that demonstrate concepts in direct current electrical resistivity, self-potential, and electromagnetic geophysical models. Explains how data profiles of the models are obtained. (DDR)

  9. rights reserved Geophysical Identification of Hydrothermally Altered

    African Journals Online (AJOL)

    ADOWIE PERE

    Geophysical Identification of Hydrothermally Altered Structures That Favour .... aircraft. Total line kilometers of 36,500 were covered in the survey. Magnetic ... tie lines occur at about 2000 metres interval in the ... visual inspection of the map.

  10. Exploring the oceans- The geophysical way

    Digital Repository Service at National Institute of Oceanography (India)

    Murthy, K.S.R.

    The evolution of the eastern continental margin of India (ECMI), the Bengal Fan and the Central Indian Basin (CIB) is a consequence of the breakup of India from the eastern Gondwanaland in Late Jurassic to Early Cretaceous. Recent marine geophysical...

  11. A geological and geophysical data collection system

    Digital Repository Service at National Institute of Oceanography (India)

    Sudhakar, T.; Afzulpurkar, S.

    A geological and geophysical data collection system using a Personal Computer is described below. The system stores data obtained from various survey systems typically installed in a charter vessel and can be used for similar applications on any...

  12. Multiscale geophysical imaging of the critical zone

    Science.gov (United States)

    Parsekian, Andy; Singha, Kamini; Minsley, Burke J.; Holbrook, W. Steven; Slater, Lee

    2015-01-01

    Details of Earth's shallow subsurface—a key component of the critical zone (CZ)—are largely obscured because making direct observations with sufficient density to capture natural characteristic spatial variability in physical properties is difficult. Yet this inaccessible region of the CZ is fundamental to processes that support ecosystems, society, and the environment. Geophysical methods provide a means for remotely examining CZ form and function over length scales that span centimeters to kilometers. Here we present a review highlighting the application of geophysical methods to CZ science research questions. In particular, we consider the application of geophysical methods to map the geometry of structural features such as regolith thickness, lithological boundaries, permafrost extent, snow thickness, or shallow root zones. Combined with knowledge of structure, we discuss how geophysical observations are used to understand CZ processes. Fluxes between snow, surface water, and groundwater affect weathering, groundwater resources, and chemical and nutrient exports to rivers. The exchange of gas between soil and the atmosphere have been studied using geophysical methods in wetland areas. Indirect geophysical methods are a natural and necessary complement to direct observations obtained by drilling or field mapping. Direct measurements should be used to calibrate geophysical estimates, which can then be used to extrapolate interpretations over larger areas or to monitor changing processes over time. Advances in geophysical instrumentation and computational approaches for integrating different types of data have great potential to fill gaps in our understanding of the shallow subsurface portion of the CZ and should be integrated where possible in future CZ research.

  13. uranium and thorium exploration by geophysical methods

    International Nuclear Information System (INIS)

    Yueksel, F.A.; Kanli, A.I.

    1997-01-01

    Radioactivity is often measured from the ground in mineral exploration. If large areas have to be investigated, it is often unsuitable to carry out the measurements with ground-bound expeditions. A geophysical method of gamma-ray spectrometry is generally applied for uranium exploration. Exploration of uranium surveys were stopped after the year of 1990 in Turkey. Therefore the real potential of uranium in Turkey have to be investigated by using the geophysical techniques

  14. The geochemical environment of nuclear fuel waste disposal

    International Nuclear Information System (INIS)

    Gascoyne, M.

    1995-01-01

    The concept for disposal of Canada's nuclear fuel waste in a geologic environment on the Canadian Shield has recently been presented by Atomic Energy of Canada Limited (AECL) to governments, scientists, and the public, for review. An important part of this concept concerns the geochemical environment of a disposal vault and includes consideration of rock and groundwater compositions, geochemical interactions between rocks, groundwaters, and emplaced vault materials, and the influences and significance of anthropogenic and microbiological effects following closure of the vault. This paper summarizes the disposal concept and examines aspects of the geochemical environment. The presence of saline groundwaters and reducing conditions at proposed vault depths (500-1000 m) in the Canadian Shield has an important bearing on the stability of the used nuclear fuel, its container, and buffer and backfill materials. The potential for introduction of anthropogenic contaminants and microbes during site investigations and vault excavation, operation, and sealing is described with examples from AECL's research areas on the Shield and in their underground research laboratory in southeastern Manitoba. (author)

  15. Geochemical prospecting for rare earth elements using termite mound materials

    Science.gov (United States)

    Horiuchi, Yu; Ohno, Tetsuji; Hoshino, Mihoko; Shin, Ki-Cheol; Murakami, Hiroyasu; Tsunematsu, Maiko; Watanabe, Yasushi

    2014-12-01

    The Blockspruit fluorite prospect, located in North West State of the Republic of South Africa, occurs within an actinolite rock zone that was emplaced into the Kenkelbos-type granite of Proterozoic age. There are a large number of termite mounds in the prospect. For geochemical prospecting for rare earth elements (REEs), in total, 200 samples of termite mound material were collected from actinolite rock and granite zones in the prospect. Geochemical analyses of these termite mound materials were conducted by two methods: portable X-ray fluorescence (XRF) spectrometry and inductively coupled plasma-mass spectrometry (ICP-MS). Comparison of the two methods broadly indicates positive correlations of REEs (La, Ce, Pr, Nd, and Y), in particular Y and La having a strong correlation. As the result of modal abundance analyses, the actinolite rock at surface mainly consists of ferro-actinolite (89.89 wt%) and includes xenotime (0.26 wt%) and monazite (0.21 wt%) grains as REE minerals. Termite mound materials from actinolite rock also contain xenotime (0.27 wt%) and monazite (0.41 wt%) grains. In addition, termite mound materials from the actinolite rock zone have high hematite and Fe silicate contents compared to those from granite zone. These relationships suggest that REE minerals in termite mound materials originate form actinolite rock. Geochemical anomaly maps of Y, La, and Fe concentrations drawn based on the result of the portable XRF analyses show that high concentrations of these elements trend from SW to NE which broadly correspond to occurrences of actinolite body. These results indicate that termite mounds are an effective tool for REE geochemical prospection in the study area for both light REEs and Y, but a more detailed survey is required to establish the distribution of the actinolite rock body.

  16. National Geophysical Data Center Tsunami Data Archive

    Science.gov (United States)

    Stroker, K. J.; Dunbar, P. K.; Brocko, R.

    2008-12-01

    NOAA's National Geophysical Data Center (NGDC) and co-located World Data Center for Geophysics and Marine Geology long-term tsunami data archive provides data and derived products essential for tsunami hazard assessment, forecast and warning, inundation modeling, preparedness, mitigation, education, and research. As a result of NOAA's efforts to strengthen its tsunami activities, the long-term tsunami data archive has grown from less than 5 gigabyte in 2004 to more than 2 terabytes in 2008. The types of data archived for tsunami research and operation activities have also expanded in fulfillment of the P.L. 109-424. The archive now consists of: global historical tsunami, significant earthquake and significant volcanic eruptions database; global tsunami deposits and proxies database; reference database; damage photos; coastal water-level data (i.e. digital tide gauge data and marigrams on microfiche); bottom pressure recorder (BPR) data as collected by Deep-ocean Assessment and Reporting of Tsunamis (DART) buoys. The tsunami data archive comes from a wide variety of data providers and sources. These include the NOAA Tsunami Warning Centers, NOAA National Data Buoy Center, NOAA National Ocean Service, IOC/NOAA International Tsunami Information Center, NOAA Pacific Marine Environmental Laboratory, U.S. Geological Survey, tsunami catalogs, reconnaissance reports, journal articles, newspaper articles, internet web pages, and email. NGDC has been active in the management of some of these data for more than 50 years while other data management efforts are more recent. These data are openly available, either directly on-line or by contacting NGDC. All of the NGDC tsunami and related databases are stored in a relational database management system. These data are accessible over the Web as tables, reports, and interactive maps. The maps provide integrated web-based GIS access to individual GIS layers including tsunami sources, tsunami effects, significant earthquakes

  17. SIAM conference on inverse problems: Geophysical applications. Final technical report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-12-31

    This conference was the second in a series devoted to a particular area of inverse problems. The theme of this series is to discuss problems of major scientific importance in a specific area from a mathematical perspective. The theme of this symposium was geophysical applications. In putting together the program we tried to include a wide range of mathematical scientists and to interpret geophysics in as broad a sense as possible. Our speaker came from industry, government laboratories, and diverse departments in academia. We managed to attract a geographically diverse audience with participation from five continents. There were talks devoted to seismology, hydrology, determination of the earth`s interior on a global scale as well as oceanographic and atmospheric inverse problems.

  18. Relationship of Worldwide Rocket Launch Crashes with Geophysical Parameters

    Directory of Open Access Journals (Sweden)

    N. Romanova

    2013-01-01

    Full Text Available A statistical comparison of launch crashes at different worldwide space ports with geophysical factors has been performed. A comprehensive database has been compiled, which includes 50 years of information from the beginning of the space age in 1957 about launch crashes occurring world-wide. Special attention has been paid to statistics concerning launches at the largest space ports: Plesetsk, Baikonur, Cape Canaveral, and Vandenberg. In search of a possible influence of geophysical factors on launch failures, such parameters as the vehicle type, local time, season, sunspot number, high-energy electron fluxes, and solar proton events have been examined. Also, we have analyzed correlations with the geomagnetic indices as indirect indicators of the space weather condition. Regularities found in this study suggest that further detailed studies of space weather effects on launcher systems, especially in the high-latitude regions, should be performed.

  19. Geophysical borehole logging. Final disposal of spent fuel

    International Nuclear Information System (INIS)

    Rouhiainen, P.

    1984-01-01

    Teollisuuden Voima Oy (Industrial Power Company Ltd.) will take precautions for final disposal of spent fuel in the Finnish bedrock. The first stage of the site selection studies includes drilling of a deep borehole down to approximately 1000 meters in the year 1984. The report deals with geophysical borehole logging methods, which could be used for the studies. The aim of geophysical borehole logging methods is to descripe specially hydrogeological and structural features. Only the most essential methods are dealt with in this report. Attention is paid to the information produced with the methods, derscription of the methods, interpretation and limitations. The feasibility and possibilities for the aims are evaluated. The evaluations are based mainly on the results from Sweden, England, Canada and USA as well as experiencies gained in Finland

  20. Investigating the temporal fluctuations in geoelectrical and geochemical signals Jointly measured in a seismic area of Southern Apennine chain (Italy

    Directory of Open Access Journals (Sweden)

    S. Piscitelli

    2001-06-01

    Full Text Available We analyse geoelectrical and geochemical time series jointly measured by means of a multiparametric automatic station close to an anomalous fluid emission in Val d'Agri (Basilicata, Southern Italy. In the investigated are some destructive seismic events occurred in past and recent years. We analysed the temporal fluctuations of the signals by spectral tools. We detected scaling behaviours in the power spectra of the time series recorded, that are typical fingerprints of fractional Brownian motions. The estimated values of the spectral indices reveal the presence of antipersistent behaviour in the time dynamics of all geoelectrical and geochemical data recorded. This work intends to improve our knowledge of the inner time dynamics of geophysical non-seismometric parameters.

  1. Space Geodesy Monitoring Mass Transport in Global Geophysical Fluids

    Science.gov (United States)

    Chao, Benjamin F.

    2004-01-01

    Mass transports occurring in the atmosphere-hydrosphere-cryosphere-solid Earth-core system (the 'global geophysical fluids') are important geophysical phenomena. They occur on all temporal and spatial scales. Examples include air mass and ocean circulations, oceanic and solid tides, hydrological water and idsnow redistribution, mantle processes such as post-glacial rebound, earthquakes and tectonic motions, and core geodynamo activities. The temporal history and spatial pattern of such mass transport are often not amenable to direct observations. Space geodesy techniques, however, have proven to be an effective tool in monitorihg certain direct consequences of the mass transport, including Earth's rotation variations, gravitational field variations, and the geocenter motion. Considerable advances have been made in recent years in observing and understanding of these geodynamic effects. This paper will use several prominent examples to illustrate the triumphs in research over the past years under a 'Moore's law' in space geodesy. New space missions and projects promise to further advance our knowledge about the global mass transports. The latter contributes to our understanding of the geophysical processes that produce and regulate the mass transports, as well as of the solid Earth's response to such changes in terms of Earth's mechanical properties.

  2. Bringing 3D Printing to Geophysical Science Education

    Science.gov (United States)

    Boghosian, A.; Turrin, M.; Porter, D. F.

    2014-12-01

    3D printing technology has been embraced by many technical fields, and is rapidly making its way into peoples' homes and schools. While there is a growing educational and hobbyist community engaged in the STEM focused technical and intellectual challenges associated with 3D printing, there is unrealized potential for the earth science community to use 3D printing to communicate scientific research to the public. Moreover, 3D printing offers scientists the opportunity to connect students and the public with novel visualizations of real data. As opposed to introducing terrestrial measurements through the use of colormaps and gradients, scientists can represent 3D concepts with 3D models, offering a more intuitive education tool. Furthermore, the tactile aspect of models make geophysical concepts accessible to a wide range of learning styles like kinesthetic or tactile, and learners including both visually impaired and color-blind students.We present a workflow whereby scientists, students, and the general public will be able to 3D print their own versions of geophysical datasets, even adding time through layering to include a 4th dimension, for a "4D" print. This will enable scientists with unique and expert insights into the data to easily create the tools they need to communicate their research. It will allow educators to quickly produce teaching aids for their students. Most importantly, it will enable the students themselves to translate the 2D representation of geophysical data into a 3D representation of that same data, reinforcing spatial reasoning.

  3. Development and implementation of the software for visualization and analysis of data geophysical loggers

    Science.gov (United States)

    Gordeev, V. F.; Malyshkov, S. Yu.; Botygin, I. A.; Sherstnev, V. S.; Sherstneva, A. I.

    2017-11-01

    The general trend of modern ecological geophysics is changing priorities towards rapid assessment, management and prediction of ecological and engineering soil stability as well as developing brand new geophysical technologies. The article describes researches conducted by using multi-canal geophysical logger MGR-01 (developed by IMCES SB RAS), which allows to measure flux density of very low-frequency electromagnetic radiation. It is shown that natural pulsed electromagnetic fields of the earthen lithosphere can be a source of new information on Earth's crust and processes in it, including earthquakes. The device is intended for logging electromagnetic processes in Earth's crust, geophysical exploration, finding structural and lithological inhomogeneities, monitoring the geodynamic movement of Earth's crust, express assessment of seismic hazards. The data is gathered automatically from observation point network in Siberia

  4. Petrographic and geochemical data for Cenozoic volcanic rocks of the Bodie Hills, California and Nevada

    Science.gov (United States)

    du Bray, Edward A.; John, David A.; Box, Stephen E.; Vikre, Peter G.; Fleck, Robert J.; Cousens, Brian L.

    2013-04-23

    Petrographic and geochemical data for Cenozoic volcanic rocks of the Bodie Hills, California and Nevada // // This report presents petrographic and geochemical data for samples collected during investigations of Tertiary volcanism in the Bodie Hills of California and Nevada. Igneous rocks in the area are principally 15–6 Ma subduction-related volcanic rocks of the Bodie Hills volcanic field but also include 3.9–0.1 Ma rocks of the bimodal, post-subduction Aurora volcanic field. Limited petrographic results for local basement rocks, including Mesozoic granitoid rocks and their metamorphic host rocks, are also included in the compilation. The petrographic data include visual estimates of phenocryst abundances as well as other diagnostic petrographic criteria. The geochemical data include whole-rock major oxide and trace element data, as well as limited whole-rock isotopic data.

  5. Geophysical survey at Tell Barri (Syria)

    Science.gov (United States)

    Florio, Giovanni; Cella, Federico; Pierobon, Raffaella; Castaldo, Raffaele; Castiello, Gabriella; Fedi, Maurizio

    2010-05-01

    in future surveys. These disturbances were much lower in the EM data, thus, these data were acquired in 7 squares having 50 m long sides, along profiles spaced 0.5 m. The acquisition rate, combined with the operator speed, resulted in an average sampling step of 0.2-0.25 m along each profile. First, the quadrature and inphase data were interpolated at a regular step of 0.5 m and visualized in false colour maps representing the spatial variation of conductivity and magnetic susceptibility, respectively. Then, corrections for zig-zag effect and heading error were applied. In both maps many elongated anomalies are visible, often crossing each other perpendicularly and arranged with a meaningful orientation with respect to the topography. This suggest a possible archaeological meaning for these anomalies. Quadrature data were processed by AGC filter to obtain an amplitude-normalized map. Data were further processed with algorithms based on spatial derivatives that can define the position of the source bodies with higher definition. Some hypothesis about the meaning of these linear anomalies include the presence of an urbanization area, with edifices and roads. The orientation of many structures in directions parallel or perpendicular to the altitude isolines may also suggest the presence of ancient defensive structures. Thus, the main result of the geophysical investigation was to highlight that the urbanized area extent is wider than known before. The fine stratification of the archaeological remains at Tell Barri site represents a major difficulty to the interpretation. During the next mission some anomalies will be the target of excavations to improve our understanding of the conductivity pattern and its interpretation.

  6. Geochemical prospecting for thorium and uranium deposits

    International Nuclear Information System (INIS)

    Boyle, R.W.

    1982-01-01

    The basic purpose of this book is to present an analysis of the various geochemical methods applicable in the search for all types of thorium and uranium deposits. The general chemistry and geochemistry of thorium and uranium are briefly described in the opening chapter, and this is followed by a chapter on the deposits of the two elements with emphasis on their indicator (pathfinder) elements and on the primary and secondary dispersion characteristics of thorium and uranium in the vicinity of their deposits. The next seven chapters form the main part of the book and describe geochemical prospecting for thorium and uranium, stressing selection of areas in which to prospect, radiometric surveys, analytical geochemical surveys based on rocks (lithochemical surveys), unconsolidated materials (pedochemical surveys), natural waters and sediments (hydrochemical surveys), biological materials (biogeochemical surveys), gases (atmochemical surveys), and miscellaneous methods. A final brief chapter reviews radiometric and analytical methods for the detection and estimation of thorium and uranium. (Auth.)

  7. Geophysical investigations applied to site selection for the radioactive waste disposal; Investigacoes geofisicas aplicadas na selecao de um repositorio de rejeitos radioativos

    Energy Technology Data Exchange (ETDEWEB)

    Saad, Samir; Dornelles, Gerson; Pedrozo, Geraldo Arholdi [Comissao Nacional de Energia Nuclear (CNEN), Rio de Janeiro, RJ (Brazil)

    1993-07-01

    In this work the geophysical exploratory techniques and the results obtained for the selection of a candidate site for the final repository of the radioactive waste containing cesium-137 generated by the Goiania accident occurred in September 1987, are described. The studies were performed in an area of about 100 hectares where is located the present radioactive waste provisional repository. the geophysical investigations using electromagnetic methods (VLF-EM), electric drillings and surface and sub-surface radiometry allowed for the area monitoring and provided the geophysical parameters necessary for understanding the structural and stratigraphic context. Furthermore, they will provide data for the geotechnical, geochemical and hydrogeological investigations as well as for the engineering conceptual project for the repository construction. (author)

  8. Development of thermodynamic databases for geochemical calculations

    International Nuclear Information System (INIS)

    Arthur, R.C.; Sasamoto, Hiroshi; Shibata, Masahiro; Yui, Mikazu; Neyama, Atsushi

    1999-09-01

    Two thermodynamic databases for geochemical calculations supporting research and development on geological disposal concepts for high level radioactive waste are described in this report. One, SPRONS.JNC, is compatible with thermodynamic relations comprising the SUPCRT model and software, which permits calculation of the standard molal and partial molal thermodynamic properties of minerals, gases, aqueous species and reactions from 1 to 5000 bars and 0 to 1000degC. This database includes standard molal Gibbs free energies and enthalpies of formation, standard molal entropies and volumes, and Maier-Kelly heat capacity coefficients at the reference pressure (1 bar) and temperature (25degC) for 195 minerals and 16 gases. It also includes standard partial molal Gibbs free energies and enthalpies of formation, standard partial molal entropies, and Helgeson, Kirkham and Flowers (HKF) equation-of-state coefficients at the reference pressure and temperature for 1147 inorganic and organic aqueous ions and complexes. SPRONS.JNC extends similar databases described elsewhere by incorporating new and revised data published in the peer-reviewed literature since 1991. The other database, PHREEQE.JNC, is compatible with the PHREEQE series of geochemical modeling codes. It includes equilibrium constants at 25degC and l bar for mineral-dissolution, gas-solubility, aqueous-association and oxidation-reduction reactions. Reaction enthalpies, or coefficients in an empirical log K(T) function, are also included in this database, which permits calculation of equilibrium constants between 0 and 100degC at 1 bar. All equilibrium constants, reaction enthalpies, and log K(T) coefficients in PHREEQE.JNC are calculated using SUPCRT and SPRONS.JNC, which ensures that these two databases are mutually consistent. They are also internally consistent insofar as all the data are compatible with basic thermodynamic definitions and functional relations in the SUPCRT model, and because primary

  9. Development of thermodynamic databases for geochemical calculations

    Energy Technology Data Exchange (ETDEWEB)

    Arthur, R.C. [Monitor Scientific, L.L.C., Denver, Colorado (United States); Sasamoto, Hiroshi; Shibata, Masahiro; Yui, Mikazu [Japan Nuclear Cycle Development Inst., Tokai, Ibaraki (Japan); Neyama, Atsushi [Computer Software Development Corp., Tokyo (Japan)

    1999-09-01

    Two thermodynamic databases for geochemical calculations supporting research and development on geological disposal concepts for high level radioactive waste are described in this report. One, SPRONS.JNC, is compatible with thermodynamic relations comprising the SUPCRT model and software, which permits calculation of the standard molal and partial molal thermodynamic properties of minerals, gases, aqueous species and reactions from 1 to 5000 bars and 0 to 1000degC. This database includes standard molal Gibbs free energies and enthalpies of formation, standard molal entropies and volumes, and Maier-Kelly heat capacity coefficients at the reference pressure (1 bar) and temperature (25degC) for 195 minerals and 16 gases. It also includes standard partial molal Gibbs free energies and enthalpies of formation, standard partial molal entropies, and Helgeson, Kirkham and Flowers (HKF) equation-of-state coefficients at the reference pressure and temperature for 1147 inorganic and organic aqueous ions and complexes. SPRONS.JNC extends similar databases described elsewhere by incorporating new and revised data published in the peer-reviewed literature since 1991. The other database, PHREEQE.JNC, is compatible with the PHREEQE series of geochemical modeling codes. It includes equilibrium constants at 25degC and l bar for mineral-dissolution, gas-solubility, aqueous-association and oxidation-reduction reactions. Reaction enthalpies, or coefficients in an empirical log K(T) function, are also included in this database, which permits calculation of equilibrium constants between 0 and 100degC at 1 bar. All equilibrium constants, reaction enthalpies, and log K(T) coefficients in PHREEQE.JNC are calculated using SUPCRT and SPRONS.JNC, which ensures that these two databases are mutually consistent. They are also internally consistent insofar as all the data are compatible with basic thermodynamic definitions and functional relations in the SUPCRT model, and because primary

  10. Overview of geochemical modeling needs for nuclear waste management

    International Nuclear Information System (INIS)

    Isherwood, D.; Wolery, T.

    1984-01-01

    Research needs include, but are not limited to: measurement of basic thermodynamic data at elevated temperatures for species identified by modelers as potentially important; evaluation of substances which control or limit precipitation and/or nucleation kinetics; sorption studies specifically designed to provide data needed for modeling. This includes the rate of sorption, desorption, and the characterization of the solid and aqueous phases; site-mixing models and thermodynamic data for secondary minerals that form solid solutions; the development of standard techniques for measuring rate laws for precipitation and dissolution kinetics; and measurement of rate laws describing redox kinetics, dissolution, and precipitation involving aqueous species and solid phases of interest to geochemical modelers

  11. Geochemical studies of backfill aggregates, lake sediment cores and the Hueco Bolson Aquifer

    Science.gov (United States)

    Thapalia, Anita

    Aquifer that an important sources of water in the El Paso/Cd. Juraez metroplex. To delineate the boundary between fresh and brackish water from the northern Hueco Bolson Aquifer, we utilize an integrative geochemical, geophysical, and sedimentological approach. The goal of this study is to use geophysical well-log analysis and the water chemical analysis for identifying the changes in the quality of the groundwater. A detailed microgravity survey is utilized to explore the subsurface geological structures that control the conduits and/or barriers of groundwater flow. A detailed geochemical analysis of aquifer samples provide salinity of groundwater that will complement to the subsurface structures obtained from the geophysical study. This fundamental research in developing methods from an integrated approach to estimate aquifer quality can be used as an analog for similar studies in other arid regions.

  12. Automatic differentiation in geophysical inverse problems

    Science.gov (United States)

    Sambridge, M.; Rickwood, P.; Rawlinson, N.; Sommacal, S.

    2007-07-01

    Automatic differentiation (AD) is the technique whereby output variables of a computer code evaluating any complicated function (e.g. the solution to a differential equation) can be differentiated with respect to the input variables. Often AD tools take the form of source to source translators and produce computer code without the need for deriving and hand coding of explicit mathematical formulae by the user. The power of AD lies in the fact that it combines the generality of finite difference techniques and the accuracy and efficiency of analytical derivatives, while at the same time eliminating `human' coding errors. It also provides the possibility of accurate, efficient derivative calculation from complex `forward' codes where no analytical derivatives are possible and finite difference techniques are too cumbersome. AD is already having a major impact in areas such as optimization, meteorology and oceanography. Similarly it has considerable potential for use in non-linear inverse problems in geophysics where linearization is desirable, or for sensitivity analysis of large numerical simulation codes, for example, wave propagation and geodynamic modelling. At present, however, AD tools appear to be little used in the geosciences. Here we report on experiments using a state of the art AD tool to perform source to source code translation in a range of geoscience problems. These include calculating derivatives for Gibbs free energy minimization, seismic receiver function inversion, and seismic ray tracing. Issues of accuracy and efficiency are discussed.

  13. Understanding biogeobatteries: Where geophysics meets microbiology

    Energy Technology Data Exchange (ETDEWEB)

    Revil, A.; Mendonca, C.A.; Atekwana, E.A.; Kulessa, B.; Hubbard, S.S.; Bohlen, K.

    2009-08-15

    Although recent research suggests that contaminant plumes behave as geobatteries that produce an electrical current in the ground, no associated model exists that honors both geophysical and biogeochemical constraints. Here, we develop such a model to explain the two main electrochemical contributions to self-potential signals in contaminated areas. Both contributions are associated with the gradient of the activity of two types of charge carriers, ions and electrons. In the case of electrons, bacteria act as catalysts for reducing the activation energy needed to exchange the electrons between electron donor and electron acceptor. Possible mechanisms that facilitate electron migration include iron oxides, clays, and conductive biological materials, such as bacterial conductive pili or other conductive extracellular polymeric substances. Because we explicitly consider the role of biotic processes in the geobattery model, we coined the term 'biogeobattery'. After theoretical development of the biogeobattery model, we compare model predictions with self-potential responses associated with laboratory and field-scale conducted in contaminated environments. We demonstrate that the amplitude and polarity of large (>100 mV) self-potential signatures requires the presence of an electronic conductor to serve as a bridge between electron donors and acceptors. Small self-potential anomalies imply that electron donors and electron acceptors are not directly interconnected, but instead result simply from the gradient of the activity of the ionic species that are present in the system.

  14. Robust statistics and geochemical data analysis

    International Nuclear Information System (INIS)

    Di, Z.

    1987-01-01

    Advantages of robust procedures over ordinary least-squares procedures in geochemical data analysis is demonstrated using NURE data from the Hot Springs Quadrangle, South Dakota, USA. Robust principal components analysis with 5% multivariate trimming successfully guarded the analysis against perturbations by outliers and increased the number of interpretable factors. Regression with SINE estimates significantly increased the goodness-of-fit of the regression and improved the correspondence of delineated anomalies with known uranium prospects. Because of the ubiquitous existence of outliers in geochemical data, robust statistical procedures are suggested as routine procedures to replace ordinary least-squares procedures

  15. Coupling of transport and geochemical models

    International Nuclear Information System (INIS)

    Noy, D.J.

    1985-01-01

    This contract stipulated separate pieces of work to consider mass transport in the far-field of a repository, and more detailed geochemical modelling of the groundwater in the near-field. It was envisaged that the far-field problem would be tackled by numerical solutions to the classical advection-diffusion equation obtained by the finite element method. For the near-field problem the feasibility of coupling existing geochemical equilibrium codes to the three dimensional groundwater flow codes was to be investigated. This report is divided into two sections with one part devoted to each aspect of this contract. (author)

  16. Methodological Developments in Geophysical Assimilation Modeling

    Science.gov (United States)

    Christakos, George

    2005-06-01

    This work presents recent methodological developments in geophysical assimilation research. We revisit the meaning of the term "solution" of a mathematical model representing a geophysical system, and we examine its operational formulations. We argue that an assimilation solution based on epistemic cognition (which assumes that the model describes incomplete knowledge about nature and focuses on conceptual mechanisms of scientific thinking) could lead to more realistic representations of the geophysical situation than a conventional ontologic assimilation solution (which assumes that the model describes nature as is and focuses on form manipulations). Conceptually, the two approaches are fundamentally different. Unlike the reasoning structure of conventional assimilation modeling that is based mainly on ad hoc technical schemes, the epistemic cognition approach is based on teleologic criteria and stochastic adaptation principles. In this way some key ideas are introduced that could open new areas of geophysical assimilation to detailed understanding in an integrated manner. A knowledge synthesis framework can provide the rational means for assimilating a variety of knowledge bases (general and site specific) that are relevant to the geophysical system of interest. Epistemic cognition-based assimilation techniques can produce a realistic representation of the geophysical system, provide a rigorous assessment of the uncertainty sources, and generate informative predictions across space-time. The mathematics of epistemic assimilation involves a powerful and versatile spatiotemporal random field theory that imposes no restriction on the shape of the probability distributions or the form of the predictors (non-Gaussian distributions, multiple-point statistics, and nonlinear models are automatically incorporated) and accounts rigorously for the uncertainty features of the geophysical system. In the epistemic cognition context the assimilation concept may be used to

  17. WLS software for the Los Alamos geophysical instrumentation truck

    International Nuclear Information System (INIS)

    Ideker, C.D.; LaDelfe, C.M.

    1985-01-01

    Los Alamos National Laboratory's capabilities for special downhole geophysical well logging has increased steadily over the past few years. Software was developed originally for each individual tool as it became operational. With little or no standardization for tool software modules, software development became redundant, time consuming, and cost ineffective. With long-term use and the rapid evolution of well logging capacity in mind. Los Alamos and EG and G personnel decided to purchase a software system. The system was designed to offer: wide-range use and programming flexibility; standardization subroutines for tool module development; user friendly operation which would reduce training time; operator error checking and alarm activation; maximum growth capacity for new tools as they are added to the inventory; and the ability to incorporate changes made to the computer operating system and hardware. The end result is a sophisticated and flexible software tool and for transferring downhole geophysical measurement data to computer disk files. This paper outlines the need, design, development, and implementation of the WLS software for geophysical data acquisition. A demonstration and working examples are included in the presentation

  18. Geophysical monitoring as an information source of rock massif behaviour

    Directory of Open Access Journals (Sweden)

    Pavel Bláha

    2008-06-01

    Full Text Available Geophysical measurements are an integral part of engineering-geological investigation where theypresent a wide range of useful information about the tested geological medium and about its geotechnicalqualities. Lately, repeated geophysical measurements in different time intervals have been used to judgethe changes occurring in the rock massif. These measurements bear the characteristics of total monitoring.This total monitoring contains series of repeated measurements and further an integrated spectrum of linkedactivities including evaluation, comparison with the warning state and making a decision about takingprecautions. From the range of geophysical methods and methodologies used for monitoring in full sensewe may mention, for example, continuous seismoacoustic measurements in mining constructions; (whichmay result even in recalling of the personnel, and further, also seismic measurements in the surroundingsof atomic power stations and measurements considering the protection against radioactive elements and their decay components.As a full monitoring we may also classify measurements in dumping sites with the aid of repeated geoelectrical measurements in the system of fixed electrodes under impermeable foils.These measurements are mostly carried out from time to time followed by taking immediate action when the foil is found damaged. In practice the term monitoring is used, although not very correctly, for all periodically repeated measurements, which do not result in taking action or interference, but supply a wide range of information about the rock massif behavior in time.

  19. Adaptive Multiscale Modeling of Geochemical Impacts on Fracture Evolution

    Science.gov (United States)

    Molins, S.; Trebotich, D.; Steefel, C. I.; Deng, H.

    2016-12-01

    Understanding fracture evolution is essential for many subsurface energy applications, including subsurface storage, shale gas production, fracking, CO2 sequestration, and geothermal energy extraction. Geochemical processes in particular play a significant role in the evolution of fractures through dissolution-driven widening, fines migration, and/or fracture sealing due to precipitation. One obstacle to understanding and exploiting geochemical fracture evolution is that it is a multiscale process. However, current geochemical modeling of fractures cannot capture this multi-scale nature of geochemical and mechanical impacts on fracture evolution, and is limited to either a continuum or pore-scale representation. Conventional continuum-scale models treat fractures as preferential flow paths, with their permeability evolving as a function (often, a cubic law) of the fracture aperture. This approach has the limitation that it oversimplifies flow within the fracture in its omission of pore scale effects while also assuming well-mixed conditions. More recently, pore-scale models along with advanced characterization techniques have allowed for accurate simulations of flow and reactive transport within the pore space (Molins et al., 2014, 2015). However, these models, even with high performance computing, are currently limited in their ability to treat tractable domain sizes (Steefel et al., 2013). Thus, there is a critical need to develop an adaptive modeling capability that can account for separate properties and processes, emergent and otherwise, in the fracture and the rock matrix at different spatial scales. Here we present an adaptive modeling capability that treats geochemical impacts on fracture evolution within a single multiscale framework. Model development makes use of the high performance simulation capability, Chombo-Crunch, leveraged by high resolution characterization and experiments. The modeling framework is based on the adaptive capability in Chombo

  20. SQUID use for Geophysics: finding billions of dollars

    Science.gov (United States)

    Foley, Catherine

    2014-03-01

    Soon after their discovery, Jim Zimmerman saw the potential of using Superconducting Quantum Interference Devices, SQUIDs, for the study of Geophysics and undertook experiments to understand the magnetic phenomena of the Earth. However his early experiments were not successful. Nevertheless up to the early 1980's, some research effort in the use of SQUIDs for geophysics continued and many ideas of how you could use SQUIDs evolved. Their use was not adopted by the mining industry at that time for a range of reasons. The discovery of high temperature superconductors started a reinvigoration in the interest to use SQUIDs for mineral exploration. Several groups around the world worked with mining companies to develop both liquid helium and nitrogen cooled systems. The realisation of the achievable sensitivity that contributed to successful mineral discoveries and delineation led to real financial returns for miners. By the mid 2000's, SQUID systems for geophysics were finally being offered for sale by several start-up companies. This talk will tell the story of SQUID use in geophysics. It will start with the early work of the SQUID pioneers including that of Jim Zimmerman and John Clarke and will also cover the development since the early 1990's up to today of a number of magnetometers and gradiometers that have been successfully commercialised and used to create significant impact in the global resources industry. The talk will also cover some of the critical technical challenges that had to be overcome to succeed. It will focus mostly on magnetically unshielded systems used in the field although some laboratory-based systems will be discussed.

  1. Geochemical reanalysis of historical U.S. Geological Survey sediment samples from the Haines area, Juneau and Skagway quadrangles, southeast Alaska

    Science.gov (United States)

    Werdon, Melanie B.; Granitto, Matthew; Azain, Jaime S.

    2015-01-01

    The State of Alaska’s Strategic and Critical Minerals (SCM) Assessment project, a State-funded Capital Improvement Project (CIP), is designed to evaluate Alaska’s statewide potential for SCM resources. The SCM Assessment is being implemented by the Alaska Division of Geological & Geophysical Surveys (DGGS), and involves obtaining new airborne-geophysical, geological, and geochemical data. As part of the SCM Assessment, thousands of historical geochemical samples from DGGS, U.S. Geological Survey (USGS), and U.S. Bureau of Mines archives are being reanalyzed by DGGS using modern, quantitative, geochemical-analytical methods. The objective is to update the statewide geochemical database to more clearly identify areas in Alaska with SCM potential. The USGS is also undertaking SCM-related geologic studies in Alaska through the federally funded Alaska Critical Minerals cooperative project. DGGS and USGS share the goal of evaluating Alaska’s strategic and critical minerals potential and together created a Letter of Agreement (signed December 2012) and a supplementary Technical Assistance Agreement (#14CMTAA143458) to facilitate the two agencies’ cooperative work. Under these agreements, DGGS contracted the USGS in Denver to reanalyze historical USGS sediment samples from Alaska. For this report, DGGS funded reanalysis of 212 historical USGS sediment samples from the statewide Alaska Geochemical Database Version 2.0 (AGDB2; Granitto and others, 2013). Samples were chosen from the Chilkat, Klehini, Tsirku, and Takhin river drainages, as well as smaller drainages flowing into Chilkat and Chilkoot Inlets near Haines, Skagway Quadrangle, Southeast Alaska. Additionally some samples were also chosen from the Juneau gold belt, Juneau Quadrangle, Southeast Alaska (fig. 1). The USGS was responsible for sample retrieval from the National Geochemical Sample Archive (NGSA) in Denver, Colorado through the final quality assurance/quality control (QA/QC) of the geochemical

  2. Magnetotelluric data collected near geophysically logged boreholes in the Espa?ola and Middle Rio Grande basins, New Mexico

    Science.gov (United States)

    Williams, Jackie M.; Rodriguez, Brian D.

    2006-01-01

    The Santa Fe region is growing rapidly. The Santa Fe Group aquifer in the Espa?ola Basin is the main source of municipal water for the region, and water shortfalls could have serious consequences. Future growth and land management in the region depend on accurate assessment and protection of the region's ground-water resources. An important issue in managing the ground-water resources is a better understanding of the hydrogeology of the Tertiary Santa Fe Group. The Santa Fe Group includes the sedimentary deposits that fill the Rio Grande rift and contain the principal ground-water aquifers. The U.S. Geological Survey (USGS) is conducting a series of multidisciplinary studies of the Espa?ola Basin in northern New Mexico. Detailed geologic mapping, high-resolution airborne magnetic surveys, electromagnetic surveys, and hydrologic, lithologic, and hydro-geochemical data are being used to better understand the aquifer systems. Magnetotelluric (MT) surveys were completed as part of these studies. The primary purpose of the MT surveys was to map changes in electrical resistivity with depth that are related to differences in various rock types that help control the properties of aquifers in the region. Resistivity modeling of the MT data can be used to investigate buried structures related to the basic geologic framework of the study area. The purpose of this report is to release MT sounding data collected near geophysically logged boreholes in the study area, including the nearby Middle Rio Grande Basin. This MT data can be used in subsequent resistivity modeling. No interpretation of the data is included in this report.

  3. Chaos theory in geophysics: past, present and future

    International Nuclear Information System (INIS)

    Sivakumar, B.

    2004-01-01

    The past two decades of research on chaos theory in geophysics has brought about a significant shift in the way we view geophysical phenomena. Research on chaos theory in geophysics continues to grow at a much faster pace, with applications to a wide variety of geophysical phenomena and geophysical problems. In spite of our success in understanding geophysical phenomena also from a different (i.e. chaotic) perspective, there still seems to be lingering suspicions on the scope of chaos theory in geophysics. The goal of this paper is to present a comprehensive account of the achievements and status of chaos theory in geophysics, and to disseminate the hope and scope for the future. A systematic review of chaos theory in geophysics, covering a wide spectrum of geophysical phenomena studied (e.g. rainfall, river flow, sediment transport, temperature, pressure, tree ring series, etc.), is presented to narrate our past achievements not only in understanding and predicting geophysical phenomena but also in improving the chaos identification and prediction techniques. The present state of chaos research in geophysics (in terms of geophysical phenomena, problems, and chaos methods) and potential for future improvements (in terms of where, why and possibly how) are also highlighted. Our popular views of nature (i.e. stochastic and deterministic), and of geophysical phenomena in particular, are discussed, and the usefulness of chaos theory as a bridge between such views is also put forth

  4. Looking Forward to the electronic Geophysical Year

    Science.gov (United States)

    Kamide, Y.; Baker, D. N.; Thompson, B.; Barton, C.; Kihn, E.

    2004-12-01

    During the International Geophysical Year (1957-1958), member countries established many new capabilities pursuing the major IGY objectives of collecting geophysical data as widely as possible and providing free access to these data for all scientists around the globe. A key achievement of the IGY was the establishment of a worldwide system of data centers and physical observatories. The worldwide scientific community has now endorsed and is promoting an electronic Geophysical Year (eGY) initiative. The proposed eGY concept would both commemorate the 50th anniversary of the IGY in 2007-2008 and would provide a forward impetus to geophysics in the 21st century, similar to that provide by the IGY fifty years ago. The eGY concept advocates the establishment of a series of virtual geophysical observatories now being deployed in cyberspace. We discuss plans to aggregate measurements into a readily accessible database along with analysis, visualization, and display tools that will make information available and useful to the scientific community, to the user community, and to the general public. We are examining the possibilities for near-realtime acquisition of data and utilization of forecast tools in order to provide users with advanced space weather capabilities. This program will provide powerful tools for education and public outreach concerning the connected Sun-Earth System.

  5. Geochemical prospect ion results of Treinta y Tres aerial photo

    International Nuclear Information System (INIS)

    Zeegers, H.; Bonnefoy, D.; Garau, M.; Spangenberg, J.

    1981-01-01

    This report shows the geochemical prospect ion results carried out within the framework of the multielemental geochemical strategy. The samples were studied by e spectrometry in the laboratories of Orleans.

  6. Geophysical images of basement rocks. Geophysical images in the Guianese basement. Airborne geophysical campaign in French Guiana - 1996

    International Nuclear Information System (INIS)

    Delor, C.; Perrin, J.; Truffert, C.; Asfirane, F.; Rossi, Ph.; Bonjoly, D.; Dubreuihl, J.; Chardon, D.

    1998-01-01

    The French Office for Geological and Mining Research (BRGM) has carried out a high sensitivity airborne geophysical survey of northern French Guiana during the second half of 1996. The aim was to realize a high resolution magnetic and gamma spectrometric mapping for future prospecting, land use and environment management. This paper describes in details the geophysical campaign, the material used, the navigation techniques, the processing of magnetic data, the gamma radiation sources used, the spectrometric calibrations and the geologic interpretation of the results. (J.S.)

  7. Geochemical fingerprints and pebbles zircon geochronology

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Earth System Science; Volume 125; Issue 7. Geochemical fingerprints and pebbles zircon geochronology: Implications for the provenance and tectonic setting of Lower Cretaceous sediments in the Zhucheng Basin (Jiaodong peninsula, North China). Jin-Long Ni Jun-Lai Liu Xiao-Ling Tang ...

  8. Kriging - a challenge in geochemical mapping

    Czech Academy of Sciences Publication Activity Database

    Štojdl, J.; Matys Grygar, Tomáš; Elznicová, J.; Popelka, J.; Váchová, T.; Hošek, Michal

    2017-01-01

    Roč. 19, APR (2017) ISSN 1607-7962. [EGU General Assembly 2017. 23.04.2017-28.04.2017, Vienna] Institutional support: RVO:61388980 Keywords : kriging * geochemical mapping Subject RIV: DD - Geochemistry http://meetingorganizer.copernicus.org/EGU2017/EGU2017-3615.pdf

  9. AfricaArray International Geophysics Field School: Applications of Near Surface Geophysics to challenges encountered in mine planning

    Science.gov (United States)

    Webb, S. J.; Jones, M. Q.; Durrheim, R. J.; Nyblade, A.; Snyman, Q.

    2012-12-01

    Hard rock exploration and mining presents many opportunities for the effective use of near surface geophysics. For over 10 years the AfricaArray international geophysics field school has been hosted at a variety of mines in South Africa. While the main objective of the field school is practical training for the next generation of geophysicists, being hosted at a mine has allowed us to investigate applications of near surface geophysics in the early stages of mine planning and development as geophysics is often cheaper and faster than drilling. Several applications include: detailed delineation of dykes and stringer dykes, physical property measurements on drill core for modeling and marker horizons, determination of overburden thickness, locations of water and faults. Dolerite dykes are usually magnetic and are associated with loss of ground (i.e. where the dyke replaces the ore and thus reduces the amount of ore available) and safety/stability concerns. Thus the accurate mapping of dykes and narrow stringers that are associated with them are crucial to the safe planning of a mine. We have acquired several case studies where ground magnetic surveys have greatly improved on the resolution and detail of airborne magnetic surveys in regions of complicated dyke swarms. In many cases, thin stringer dykes of less than 5 cm have been detected. Physical property measurements of these dykes can be used to distinguish between different ages of dykes. It is important to accurately determine overburden thickness when planning an open pit mine as this directly affects the cost of development. Depending on the nature of the overburden, both refraction seismic and or DC resistivity can provide continuous profiling in the area of interest that fills in gaps between boreholes. DC resistivity is also effective for determining water associated with dykes and structures that may affect mine planning. The field school mainly addresses the training of a variety of students. The core

  10. Virtual Geophysics Laboratory: Exploiting the Cloud and Empowering Geophysicsts

    Science.gov (United States)

    Fraser, Ryan; Vote, Josh; Goh, Richard; Cox, Simon

    2013-04-01

    source tools. While developed to provide the geophysics research community with a sustainable platform and scalable infrastructure; VGL has also developed a number of concepts, patterns and generic components of which have been reused for cases beyond geophysics, including natural hazards, satellite processing and other areas requiring spatial data discovery and processing. Future plans for VGL include a number of improvements in both functional and non-functional areas in response to its user community needs and advancement in information technologies. In particular, research is underway in the following areas (a) distributed and parallel workflow processing in the cloud, (b) seamless integration with various cloud providers, and (c) integration with virtual laboratories representing other science domains. Acknowledgements: VGL was developed by CSIRO in collaboration with Geoscience Australia, National Computational Infrastructure, Australia National University, Monash University and University of Queensland, and has been supported by the Australian Government's Education Investment Funds through NeCTAR.

  11. Appliance of geochemical engineering in radioactive waste disposal

    International Nuclear Information System (INIS)

    Li Shuang; Zhang Chengjiang; Ni Shijun; Li Kuanliang

    2008-01-01

    The basic foundation of applying geochemical engineering to control environment, common engineering models of disposal radioactive waste and the functions of the engineering barriers are introduced in this paper. The authors take the geochemical engineering barrier materiel research of a radioactive waste repository as an example to explain the appliance of geochemical engineering in the disposal of radioactive waste. And the results show that it can enhance the security of the nuclear waste repository if we use geochemical engineering barrier. (authors)

  12. Brief overview of geophysical probing technology

    International Nuclear Information System (INIS)

    Ramirez, A.L.; Lytle, R.J.

    1982-01-01

    An evaluation of high-resolution geophysical techniques which can be used to characterize a nulcear waste disposal site is being conducted by the Lawrence Livermore National Laboratory (LLNL) at the request of the US Nuclear Regulatory Commisson (NRC). LLNL is involved in research work aimed at evaluating the current capabilities and limitations of geophysical methods used for site selection. This report provides a brief overview of the capabilities and limitations associated with this technology and explains how our work addresses some of the present limitations. We are examining both seismic and electromagnetic techniques to obtain high-resolution information. We are also assessing the usefulness of geotomography in mapping fracture zones remotely. Finally, we are collecting core samples from a site in an effort to assess the capability of correlating such geophysical data with parameters of interest such as fracture continuity, orientation, and fracture density

  13. Compilation of kinetic data for geochemical calculations

    International Nuclear Information System (INIS)

    Arthur, R.C.; Savage, D.; Sasamoto, Hiroshi; Shibata, Masahiro; Yui, Mikazu

    2000-01-01

    Kinetic data, including rate constants, reaction orders and activation energies, are compiled for 34 hydrolysis reactions involving feldspars, sheet silicates, zeolites, oxides, pyroxenes and amphiboles, and for similar reactions involving calcite and pyrite. The data are compatible with a rate law consistent with surface reaction control and transition-state theory, which is incorporated in the geochemical software package EQ3/6 and GWB. Kinetic data for the reactions noted above are strictly compatible with the transition-state rate law only under far-from-equilibrium conditions. It is possible that the data are conceptually consistent with this rate law under both far-from-equilibrium and near-to-equilibrium conditions, but this should be confirmed whenever possible through analysis of original experimental results. Due to limitations in the availability of kinetic data for mine-water reactions, and in order to simplify evaluations of geochemical models of groundwater evolution, it is convenient to assume local-equilibrium in such models whenever possible. To assess whether this assumption is reasonable, a modeling approach accounting for couple fluid flow and water-rock interaction is described that can be use to estimate spatial and temporal scale of local equilibrium. The approach is demonstrated for conditions involving groundwater flow in fractures at JNC's Kamaishi in-situ tests site, and is also used to estimate the travel time necessary for oxidizing surface waters to migrate to the level of a HLW repository in crystalline rock. The question of whether local equilibrium is a reasonable assumption must be addressed using an appropriate modeling approach. To be appropriate for conditions at the Kamaishi site using the modeling approach noted above, the fracture fill must closely approximate a porous mine, groundwater flow must be purely advective and diffusion of solutes across the fracture-host rock boundary must not occur. Moreover, the mineralogical and

  14. Nuclear data for geophysical spectroscopic logging

    International Nuclear Information System (INIS)

    Schweitzer, J.S.; Hertzog, R.C.; Soran, P.D.

    1987-01-01

    Nuclear geochemical analysis requires the quantitative measurement of elemental concentrations of trace elements, as well as major elements in widely varying concentrations. This requirement places extreme demands on the quality of the spectroscopic measurements, data rates, and relating observed γ-ray intensities to the original elemental concentration. The relationship between γ-ray intensities and elemental concentration is critically dependent on the specific reaction cross sections and their uncertainties. The elements of highest priority for subsurface geochemical analysis are considered with respect to the importance of competing reactions and the neutron energy regions that are most significant. (author)

  15. Geochemical modelling: what phenomena are missing

    International Nuclear Information System (INIS)

    Jacquier, P.

    1989-12-01

    In the framework of safety assessment of radioactive waste disposal, retention phenomena are usually taken into account by the Kd concept. It is well recognized that this concept is not enough for safety assessment models, because of the several and strong assumptions which are involved in this kind of representation. One way to have a better representation of the retention phenomena, is to substitute for this Kd concept an explicit description of geochemical phenomena and then couple transport codes with geochemical codes in a fully or a two-step procedure. We use currently such codes, but the scope of this paper is to display the limits today of the geochemical modelling in connection with sites analysis for deep disposal. In this paper, we intend to give an overview of phenomena which are missing in the geochemical models, or which are not completely introduced in the models. We can distinguish, on one hand phenomena for which modelling concepts exist such as adsorption/desorption and, on the other hand, phenomena for which modelling concepts do not exist for the moment such as colloids, and complexation by polyelectrolyte solutions (organics). Moreover we have to take care of very low concentrations of radionuclides, which can be expected from the leaching processes in the repository. Under those conditions, some reactions may not occur. After a critical review of the involved phenomena, we intend to stress the main directions of the wishful evolution of the geochemical modelling. This evolution should improve substantially the quality of the above-mentioned site assessments

  16. Geochemical mapping study of Panjang island

    International Nuclear Information System (INIS)

    Sutisna; Sumardjo

    2010-01-01

    Impact of industrial and regional development are not only related to an improvement of socio-economic, but also to an environmental conservation and sustainable. This impact could be observed on a change of geochemical mapping before and after an operational of the industry. In the relation with a regional development and resources utilization, the geochemical mapping have been done in the aim to know a resources and an elemental distribution at Panjang island. In this research, ko-Instrumental Neutron Activation Analysis (k_0-INAA) have been applied in an elemental quantification on the geochemical mapping. Pencuplikan of geochemical sample have been carried out by using a grid systematic method with a sample density of about 10 sample per square kilometre involved 85 pencuplikan point. The geochemical sample of sediment and soil have been provided as a dry weight of 100 mesh. Internal quality control have done by using a number of Standard Reference Materials obtained from US. Geological Survey. Fifteen elements of Sc, Co, In, Rb, Mo, Ba, Ce, Nd, Eu, La, Yb, Th, U, lr and Hf contained in standard materials have been evaluated. The analysis result show that a relative standard deviation less than 11 %, except for Mo (13 %) and lr (26 %). Fourteen elements of Al, Br, Ca, Co, Eu, Fe, La, U, Na, Ce, Mn, As, Sc and Th have been mapped and presented in this paper. The major elements of Ca, Al and Fe, and minor elements of Mn, U and Sc are distributed at all region. The lanthanide elements of La, Ce and Eu have vary concentration and could be found at the middle to the north of the island. (author)

  17. Geochemical baseline studies of soil in Finland

    Science.gov (United States)

    Pihlaja, Jouni

    2017-04-01

    The soil element concentrations regionally vary a lot in Finland. Mostly this is caused by the different bedrock types, which are reflected in the soil qualities. Geological Survey of Finland (GTK) is carrying out geochemical baseline studies in Finland. In the previous phase, the research is focusing on urban areas and mine environments. The information can, for example, be used to determine the need for soil remediation, to assess environmental impacts or to measure the natural state of soil in industrial areas or mine districts. The field work is done by taking soil samples, typically at depth between 0-10 cm. Sampling sites are chosen to represent the most vulnerable areas when thinking of human impacts by possible toxic soil element contents: playgrounds, day-care centers, schools, parks and residential areas. In the mine districts the samples are taken from the areas locating outside the airborne dust effected areas. Element contents of the soil samples are then analyzed with ICP-AES and ICP-MS, Hg with CV-AAS. The results of the geochemical baseline studies are published in the Finnish national geochemical baseline database (TAPIR). The geochemical baseline map service is free for all users via internet browser. Through this map service it is possible to calculate regional soil baseline values using geochemical data stored in the map service database. Baseline data for 17 elements in total is provided in the map service and it can be viewed on the GTK's web pages (http://gtkdata.gtk.fi/Tapir/indexEN.html).

  18. Alligator Rivers Analogue project. Geochemical Data Bases

    International Nuclear Information System (INIS)

    Bennett, D.G.; Read, D.

    1992-01-01

    The Koongarra uranium deposit in the Northern Territory of Australia is being studied to evaluate the processes involved in the geochemical alteration of the ore body and the formation of the uranium dispersion fan. A broad range of research is being undertaken into the geochemistry and hydrology of the site with the aim of understanding the transport of radionuclides through the system. During the project a range of geochemical and hydrogeochemical models have been developed to account for measured data from the site and with which to predict site evolution. The majority of these models are based on the premise of thermodynamic chemical equilibrium and employ fundamental thermodynamic data to characterise the chemistry of the system. From the differences which exist between the thermodynamic data bases (Appendices I and II) it is possible to gain a view of the level of uncertainty associated with thermodynamic data in each set of calculations. This report gives a brief introduction to the geochemical processes underlying the models, and details the equations used to quantify the more common of these processes (e.g. aqueous speciation and mineral solubility). A description is given of the computer codes (EQ3/6, PHREEQE, MINTEQ) most commonly used during the project for geochemical modelling. Their key features are highlighted and comparisons made. It is concluded that the degree of uncertainty in geochemical modelling studies arising as a result of using one code rather than another is relatively insignificant when compared to that related to differences in the underlying data bases. 73 refs., 3 figs

  19. Geologic and geochemical studies of the New Albany Shale Group (Devonian-Mississippian) in Illinois. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Bergstrom, R.E.; Shimp, N.F.

    1980-06-30

    The Illinois State Geological Survey is conducting geological and geochemical investigations to evaluate the potential of New Albany Group shales as a source of hydrocarbons, particularly natural gas. Geological studies include stratigraphy and structure, mineralogic and petrographic characterization; analyses of physical properties; and development of a computer-based resources evaluation system. Geochemical studies include organic carbon content and trace elements; hydrocarbon content and composition; and adsorption/desorption studies of gas through shales. Separate abstracts have been prepared for each task reported.

  20. Geophysical experiments at Mariano Lake uranium orebody

    International Nuclear Information System (INIS)

    Thompson, D.T.

    1980-01-01

    Several geophysical experiments were performed over the Mariano Lake orebody before mining. Surface self-potential methods, surface-to-hole induced-polarization methods, and reflection-seismic methods were used. These geophysical techniques provided data which relate to the conceptual model of this orebody. Currents generated in the productive formation by oxidation-reduction reactions do not generate measurable potential anomalies at the surface. Surface-to-hole induced-polarization measurements apparently can detect an oxidation-reduction front in the vicinity of an exploration borehole. Reflection-seismic techniques can provide information concening the paleostructure of the area

  1. Geophysical methods for evaluation of plutonic rocks

    International Nuclear Information System (INIS)

    Gibb, R.A.; Scott, J.S.

    1986-04-01

    Geophysical methods are systematically described according to the physical principle and operational mode of each method, the type of information produced, limitations of a technical and/or economic nature, and the applicability of the method to rock-mass evaluation at Research Areas of the Nuclear Fuel Waste Management Program. The geophysical methods fall into three categories: (1) airborne and other reconnaissance surveys, (2) detailed or surface (ground) surveys, and (3) borehole or subsurface surveys. The possible roles of each method in the site-screening and site-evaluation processes of disposal vault site selection are summarized

  2. Geochemical investigation of UMTRAP designated site at Durango, Colorado

    International Nuclear Information System (INIS)

    Markos, G.; Bush, K.J.

    1983-09-01

    This report is the result of a geochemical investigation of the former uranium mill and tailings site at Durango, Colorado. This is one in a series of site specific geochemical investigations performed on the inactive uranium mill tailings included in the UMTRA Project. The objectives of the investigation are to characterize the geochemistry, to determine the contaminant distribution resulting from the former milling activities and tailings, and to infer chemical pathways and transport mechanisms from the contaminant distribution. The results will be used to model contaminant migration and to develop criteria for long-term containment media such as a cover system which is impermeable to contaminant migration. This report assumes a familiarity with the hydrologic conditions of the site and the geochemical concepts underlying the investigation. The results reported are based on a one-time sampling of waters and solid material from the background, the area adjacent to the site, and the site. The solid samples are water extracted remove easily soluble salts and acids extracted to remove cabonates and hydroxides. The water extracts and solid samples were analyzed for the major and trace elements. A limited number of samples were analyzed for radiological components. The report includes the methods of sampling, sample processing, analysis, and data interpretation. Three major conclusions are: (1) carbonate salts and low TDS characterize the tailings; (2) the adjacent area and raffinate ponds contain contaminants deposited by a single event of fluid permeation of the soils; and (3) the Animas River adjacent to the site has elevated gross alpha activity attributed to 226 Ra in the sediments derived from the tailings or milling activities

  3. GeoFramework: A Modeling Framework for Solid Earth Geophysics

    Science.gov (United States)

    Gurnis, M.; Aivazis, M.; Tromp, J.; Tan, E.; Thoutireddy, P.; Liu, Q.; Choi, E.; Dicaprio, C.; Chen, M.; Simons, M.; Quenette, S.; Appelbe, B.; Aagaard, B.; Williams, C.; Lavier, L.; Moresi, L.; Law, H.

    2003-12-01

    As data sets in geophysics become larger and of greater relevance to other earth science disciplines, and as earth science becomes more interdisciplinary in general, modeling tools are being driven in new directions. There is now a greater need to link modeling codes to one another, link modeling codes to multiple datasets, and to make modeling software available to non modeling specialists. Coupled with rapid progress in computer hardware (including the computational speed afforded by massively parallel computers), progress in numerical algorithms, and the introduction of software frameworks, these lofty goals of merging software in geophysics are now possible. The GeoFramework project, a collaboration between computer scientists and geoscientists, is a response to these needs and opportunities. GeoFramework is based on and extends Pyre, a Python-based modeling framework, recently developed to link solid (Lagrangian) and fluid (Eulerian) models, as well as mesh generators, visualization packages, and databases, with one another for engineering applications. The utility and generality of Pyre as a general purpose framework in science is now being recognized. Besides its use in engineering and geophysics, it is also being used in particle physics and astronomy. Geology and geophysics impose their own unique requirements on software frameworks which are not generally available in existing frameworks and so there is a need for research in this area. One of the special requirements is the way Lagrangian and Eulerian codes will need to be linked in time and space within a plate tectonics context. GeoFramework has grown beyond its initial goal of linking a limited number of exiting codes together. The following codes are now being reengineered within the context of Pyre: Tecton, 3-D FE Visco-elastic code for lithospheric relaxation; CitComS, a code for spherical mantle convection; SpecFEM3D, a SEM code for global and regional seismic waves; eqsim, a FE code for dynamic

  4. Development of thermodynamic databases and geochemical/transport models for prediction of long-term radionuclide migration (Germany)

    International Nuclear Information System (INIS)

    Kienzler, B.

    2000-01-01

    The isolation capacity of a repository system for radionuclides is described by geochemical modeling. The models for interpretation of experimental findings and for long-term extrapolation of experimental results are based on thermodynamic approaches. The geochemical models include dissolution reactions of waste forms, the evolution of the geochemical milieu, interactions of radionuclides with constituents of the groundwater (brines) and the precipitation of new solid phases. Reliable thermodynamic data, understanding of radionuclide complexation in aqueous multi-electrolyte solutions at the relevant ionic strength and knowledge on the formation of pure and mixed solids and on sorption processes are urgently needed for such model calculations. (author)

  5. Evidence for a critical Earth: the New Geophysics

    Science.gov (United States)

    Crampin, Stuart; Gao, Yuan

    2015-04-01

    Phenomena that are critical-systems verging on criticality with 'butterfly wings' sensitivity are common - the weather, climate change; stellar radiation; the New York Stock Exchange; population explosions; population collapses; the life cycle of fruit-flies; and many more. It must be expected that the Earth, an archetypal complex heterogeneous interactive phenomena, is a critical-system, hence there is a New Geophysics imposing fundamentally new properties on conventional sub-critical geophysics. We shall show that, despite shear waves and shear-wave splitting (SWS) being observationally neglected, azimuthally-varying stress-aligned SWS is nearly universally observed throughout the Earth's crust and uppermost ~400km of the mantle. Caused by stress-aligned fluid-saturated microcracks (intergranular films of hydrolysed melt in the mantle), the microcracks are so closely-spaced that they verge on failure in fracturing and earthquakes. Phenomena that verge on failure in this way are critical-systems which impose a range of fundamental-new properties on conventional sub-critical geophysics including: self-similarity; monitorability; calculability; predictability; controllability; universality; and butterfly wings' sensitivity. We shall show how these phenomena have been consistently observed along millions of source-to-receiver ray paths confirming the New Geophysics. New Geophysics helps to explain many otherwise inexplicable observations including a number of geophysical conundrums such as the Gutenberg-Richter relationship which is used to describe the behaviour of conventional classic geophysics despite being massively non-linear. The great advantage of the critical Earth is that, unlike other critical-systems, the progress towards criticality can be monitored at almost any point within the deep interior of the material, by analysing observations of seismic SWS. This gives an unrivalled understanding of the detailed behaviour of a particular critical-system. This

  6. Annals of the International Geophysical Year solar radio emission during the International Geophysical Year

    CERN Document Server

    Smerd, S F

    1969-01-01

    Annals of the International Geophysical Year, Volume 34: Solar Radio Emission During the International Geophysical Year covers the significant solar radio emission events observed during the International Geophysical Year (IGY). This book is composed of six chapters, and begins with a summary of tabulated quantities describing solar radio emission during the IGY. The tabulated figures illustrate the method of recording the position of radio sources on the sun, the use of symbols in describing the structure of bursts observed at single frequencies, and the different types used in a spectral

  7. Geophysical Investigations in the Caucasus (1925 - 2012): Initial, Basic and Modern Stages

    Science.gov (United States)

    Eppelbaum, L. V.

    2012-04-01

    testing different geophysical methods and methodologies in complicated environments. Airborne magnetic and gravity surveys covered all the Caucasus, regional seismic and magnetotelluric studies were used as reference profiles for deep structure investigation. Numerous effective applications of geophysical methods for searching ore, oil&gas deposits, building raw, fresh water localization, solving engineering, etc. was demonstrated. Seismological investigations (including different methods) were widely applied throughout the entire Caucasian region. Satellite geophysical examinations were successfully combined with other methods. Finally, destruction of the former Soviet Union in 1991 (beginning of the modern stage) caused a sharp common decreasing of the geophysical activity in this region. Only foreign oil-&gas companies (mainly American and England) demonstrated some industrial geophysical activity basically in the Caspian Sea. In the last few years the situation began to straighten out, especially in the field of seismology. This presentation is based of the author's experience (e.g., Eppelbaum, 1989, 1991, 2009; Eppelbaum et al., 1987; Eppelbaum and Finkelstein, 1998; Eppelbaum and Khesin, 1988, 1992, 2002, 2004, 2011, 2012; Eppelbaum and Mishne, 2011; Eppelbaum et al., 2003, 2004; Khesin et al., 1988, 1993a, 1993b, 1996, 1997; Khesin and Eppelbaum, 1986, 1994, 1997, 2007; Pilchin and Eppelbaum, 1997, 2011) and corresponding publications and reviews of other authors.

  8. A portable marine geophysical data access and management system

    Digital Repository Service at National Institute of Oceanography (India)

    Kunte, P.D.; Narvekar, P.

    Geophysical Oracle Database Management System (GPODMS) that is residing on UNIX True 64 Compaq Alpha server. GPODMS is a stable Oracle database system for longterm storage and systematic management of geophysical data and information of various disciplines...

  9. Overview of Effective Geophysical Methods Used in the Study of ...

    African Journals Online (AJOL)

    Abstract. The Application of various Geophysical Techniques for the assessment of the extent of ... ineffective Geophysical Method may not give true picture of the overall level of pollution in the .... stations shut down or maintenance which halt ...

  10. Evaluation of some Geophysical and Physicochemical ...

    African Journals Online (AJOL)

    PROF HORSFALL

    2018-04-18

    Apr 18, 2018 ... spill point parallel to the pipeline right of way. A research work carried ... of soils has been known to affect soil physio-chemical properties, which in .... The results of the geophysical analysis from the study area are presented ...

  11. Hydro geophysical Investigation for Groundwater Development at ...

    African Journals Online (AJOL)

    ADOWIE PERE

    Environ. Manage. May. 2017. Vol. 21 (3) 527-535. Full-text Available Online at ... is of equal importance with the air we breathe in ... numerical modeling solutions. The electrical geophysical survey method is the .... VES data at twelve (12) sounding points as shown in figure 2; five along traverse one; two along traverse two,.

  12. Early geophysical maps published by A. Petermann

    Czech Academy of Sciences Publication Activity Database

    Kozák, Jan; Vaněk, Jiří

    2012-01-01

    Roč. 56, č. 4 (2012), s. 1109-1122 ISSN 0039-3169 Institutional research plan: CEZ:AV0Z30120515 Keywords : August Petermann * Geographische Mitteilungen * geophysical maps Subject RIV: DC - Siesmology, Volcanology, Earth Structure Impact factor: 0.975, year: 2012

  13. Atmospheric and Geophysical Sciences Division Program Report, 1988--1989

    Energy Technology Data Exchange (ETDEWEB)

    1990-06-01

    In 1990, the Atmospheric and Geophysical Sciences Division begins its 17th year as a division. As the Division has grown over the years, its modeling capabilities have expanded to include a broad range of time and space scales ranging from hours to decades and from local to global. Our modeling is now reaching out from its atmospheric focus to treat linkages with the oceans and the land. In this report, we describe the Division's goal and organizational structure. We also provide tables and appendices describing the Division's budget, personnel, models, and publications. 2 figs., 1 tab.

  14. Developing geophysical monitoring at Mayon volcano, a collaborative project EOS-PHIVOLCS

    Science.gov (United States)

    Hidayat, D.; Laguerta, E.; Baloloy, A.; Valerio, R.; Marcial, S. S.

    2011-12-01

    Mayon is an openly-degassed volcano, producing mostly small, frequent eruptions, most recently in Aug-Sept 2006 and Dec 2009. Mayon volcano status is level 1 with low seismicity dominated mostly local and regional tectonic earthquakes with continuous emission of SO2 from its crater. A research collaboration between Earth Observatory of Singapore-NTU and Philippine Institute of Volcanology and Seismology (PHIVOLCS) have been initiated in 2010 with effort to develop a multi-disciplinary monitoring system around Mayon includes geophysical monitoring, gas geochemical monitoring, and petrologic studies. Currently there are 4 broadband seismographs, 3 short period instruments, and 4 tiltmeters. These instruments will be telemetered to the Lignon Hill Volcano Observatory through radio and 3G broadband internet. We also make use of our self-made low-cost datalogger which has been operating since Jan 2011, performing continuous data acquisition with sampling rate of 20 minute/sample and transmitted through gsm network. First target of this monitoring system is to obtain continuous multi parameter data transmitted in real time to the observatory from different instruments. Tectonically, Mayon is located in the Oas Graben, a northwest-trending structural depression. Previous study using InSAR data, showing evidence of a left-lateral oblique slip movement of the fault North of Mayon. Understanding on what structures active deformation is occurring and how deformation signal is currently partitioned between tectonic and volcanic origin is a key for characterizing magma movement in the time of unrest. Preliminary analysis of the tangential components of tiltmeters (particularly the stations 5 and 7.5 NE from the volcano) shows gradual inflation movement over a few months period. The tangential components for tiltmeters are roughly perpendicular to the fault north of Mayon. This may suggest downward tilting of the graben in the northern side of Mayon. Another possibility is that

  15. 25 CFR 211.56 - Geological and geophysical permits.

    Science.gov (United States)

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Geological and geophysical permits. 211.56 Section 211.56... FOR MINERAL DEVELOPMENT Rents, Royalties, Cancellations and Appeals § 211.56 Geological and geophysical permits. Permits to conduct geological and geophysical operations on Indian lands which do not...

  16. 25 CFR 212.56 - Geological and geophysical permits.

    Science.gov (United States)

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Geological and geophysical permits. 212.56 Section 212.56... FOR MINERAL DEVELOPMENT Rents, Royalties, Cancellations, and Appeals § 212.56 Geological and geophysical permits. (a) Permits to conduct geological and geophysical operations on Indian lands which do not...

  17. Uranium geochemical exploration in northwestern Luzon

    International Nuclear Information System (INIS)

    Santos, G. Jr.; Fernandez, L.; Ogena, M.; Tauli, G.

    1980-01-01

    A reconnaissance geochemical stream water and sediment survey which was conducted in northwestern Luzon was able to detect ten (10) uranium anomalous areas. These anomalous areas are located along a north-south trending zone of Miocene marine clastics and sedimentary rocks with tuffaceous sediment intercalations. In general, northwest Luzon has low radioactivity except for two anomalous areas which have 3 to 6 times background radioactivity. Radon anomalies occur in sparsely scattered locations. The anomalous zones appear to be related to major north-south faults and secondary northeast-southwest trending structures. Geochemical correlations between uranium and other elements such as copper, lead, zinc, manganese, silver, cobalt and nickel are generally very poor. (author)

  18. Retention/sorption and geochemical modelling

    Energy Technology Data Exchange (ETDEWEB)

    Arcos, D.; Grandia, F.; Domenech, C. [Enviros Spain, S.L., Barcelona (Spain); SCK-CEN, Mol (Belgium); Sellin, P. [SKB - Swedish Nuclear Fuel and Waste Management, SE, Stockholm (Sweden); Hunter, F.M.I.; Bate, F.; Heath, T.G.; Hoch, A. [Serco Assurance, Oxfordshire (United Kingdom); Werme, L.O. [SKB - Svensk Karnbranslehantering AB, Stockholm (Sweden); Bruggeman, C.; Maes, I.A.; Breynaert, E.; Vancluysen, J. [Leuven Katholieke Univ., Lab. for Colloid Chemistry (Belgium); Montavon, G.; Guo, Z. [Ecole des Mines, 44 - Nantes (France); Riebe, B.; Bunnenberg, C.; Meleshyn, A. [Leibniz Univ. Hannover, Zentrum fur Strahlenschutz und Radiookologie, Hannover (Germany); Dultz, S. [Leibniz Univ. Hannover, Institut fur Bodenkunde, Hannover (Germany)

    2007-07-01

    This session gathers 4 articles dealing with: the long-term geochemical evolution of the near field of a KBS-3 HLNW repository: insights from reactive transport modelling (D. Arcos, F. Grandia, C. Domenech, P. Sellin); the investigation of iron transport into bentonite from anaerobically corroding steel: a geochemical modelling study (F.M.I. Hunter, F. Bate, T.G. Heath, A. Hoch, L.O. Werme); SeO{sub 3}{sup 2-} adsorption on conditioned Na-illite: XAS spectroscopy, kinetics, surface complexation model and influence of compaction (C. Bruggeman, A. Maes, G. Montavon, E. Breynaert, Z. Guo, J. Vancluysen); the influence of temperature and gamma-irradiation on the anion sorption capacity of modified bentonites (B. Riebe, C. Bunnenberg, A. Meleshyn, S. Dultz)

  19. Geochemical approach to evaluate deforest of mangroves

    OpenAIRE

    Ishiga, Hiroaki; Diallo, Ibrahima M'bemba; Bah Mamadou Lamine Malick,; Ngulimi. Faustine Miguta,; Magai. Paschal Justin,; Shati Samwel Stanley,

    2016-01-01

    Processes of mangrove deforest related human activities were examined. To evaluate changes of soil feature, multielements geochemical compositions of mangrove muds and soils of deforest were analyzed. To describe present situation of the mangrove, Conakry in Guinea, Dar es Salaam in Tanzania, Sundarbans of Bangladesh and Nago in Okinawa of Japan were selected. Soil samples of the forests were evaluated enrichment of biologically concentrated heavy metals such as Zn, Cu and Fe, and TS (total s...

  20. Synthesizing Earth's geochemical data for hydrogeochemical analysis

    Science.gov (United States)

    Brantley, S. L.; Kubicki, J.; Miller, D.; Richter, D.; Giles, L.; Mitra, P.

    2007-12-01

    For over 200 years, geochemical, microbiological, and chemical data have been collected to describe the evolution of the surface earth. Many of these measurements are data showing variations in time or in space. To forward predict hydrologic response to changing tectonic, climatic, or anthropogenic forcings requires synthesis of these data and utilization in hydrogeochemical models. Increasingly, scientists are attempting to synthesize such data in order to make predictions for new regions or for future time periods. However, to make such complex geochemical data accessible requires development of sophisticated cyberinfrastructures that both invite uploading as well as usage of data. Two such cyberinfrastructure (CI) initiatives are currently developing, one to invite and promote the use of environmental kinetics data (laboratory time course data) through ChemxSeer, and the other to invite and promote the use of spatially indexed geochemical data for the Earth's Critical Zone through CZEN.org. The vision of these CI initiatives is to provide cyber-enhanced portals that encourage domain scientists to upload their data before publication (in private cyberspace), and to make these data eventually publicly accessible (after an embargo period). If the CI can be made to provide services to the domain specialist - e.g. to provide data analysis services or data comparison services - we envision that scientists will upload data. In addition, the CI can promote the use and comparison of datasets across disciplines. For example, the CI can facilitate the use of spatially indexed geochemical data by scientists more accustomed to dealing with time-course data for hydrologic flow, and can provide user-friendly interfaces with CI established to facilitate the use of hydrologic data. Examples of the usage of synthesized data to predict soil development over the last 13ky and its effects on active hydrological flow boundaries in surficial systems will be discussed for i) a N

  1. Summary report on geochemical barrier special study

    International Nuclear Information System (INIS)

    1988-12-01

    Long-term management of uranium mill tailings must provide assurance that soluble contaminants will not migrate beyond the Point of Compliance. Conventional management alternatives provide containment through the use of physical barriers which are designed to prevent migration of water through the tailings pile. An alternative is to geochemically modify the tailings to immobilize the contaminants. This investigation examined three potential geochemical modifiers to determine their ability to immobilize inorganic groundwater contaminants found in uranium mill tailings. These modifiers were hydrated lime (Ca(OH) 2 ), limestone (CaCO 3 ), and a sphaegnum peat moss. This investigation focused on both the geochemical interactions between the tailings and the modifiers, and the effects the modifiers had on the physical strength of the tailings. The geochemical investigations began with characterization of the tailings by X-ray diffraction and scanning electron microscopy. This was followed by batch leaching experiments in which various concentrations of each modifier were added to tailings in shaker flasks and allowed to come to equilibrium. Finally, column experiments were conducted to simulate flow through a tailings pile. The results show that all of the modifiers were at least moderately effective at immobilizing most of the groundwater contaminants of concern at uranium mill tailings sites. Hydrated lime was able to achieve 90 percent concentration reduction of arsenic, cadmium, selenium, uranium, and sulfate when added at a two percent concentration. Limestone was somewhat less effective and peat removed greater than 90 percent of arsenic, lead, uranium, and sulfate at a one percent concentration. The column tests showed that kinetic and/or mass transfer limitations are important and that sufficient time must be allowed for the immobilization reactions to occur

  2. Sharp fronts within geochemical transport problems

    International Nuclear Information System (INIS)

    Grindrod, P.

    1995-01-01

    The authors consider some reactive geochemical transport problems in groundwater systems. When incoming fluid is in disequilibrium with the mineralogy sharp transition fronts may develop. They show that this is a generic property for a class of systems where the timescales associated with reaction and diffusion phenomena are much shorter than those associated with advective transport. Such multiple timescale problems are relevant to a variety of processes in natural systems: mathematically methods of singular perturbation theory reduce the dimension of the problems to be solved locally. Furthermore, they consider how spatial heterogeneous mineralogy can impact upon the propagation of sharp geochemical fronts. The authors developed an asymptotic approach in which they solve equations for the evolving geometry of the front and indicate how the non-smooth perturbations due to natural heterogeneity of the mineralogy on underlying ground water flow field are balanced against the smoothing effect of diffusion/dispersive processes. Fronts are curvature damped, and the results here indicate the generic nature of separate front propagation within both model (idealized) and natural (heterogeneous) geochemical systems

  3. Geochemical and geo-electrical study of mud pools at the Mutnovsky volcano (South Kamchatka, Russia): Behavior of elements, structures of feeding channels and a model of origin

    International Nuclear Information System (INIS)

    Bessonova, E.P.; Bortnikova, S.B.; Gora, M.P.; Manstein, Yu.A.; Shevko, A.Ya.; Panin, G.L.; Manstein, A.K.

    2012-01-01

    This study presents data on the geochemical composition of boiling mud pools at the Mutnovsky volcano. The physicochemical characteristics of the pools and the concentrations of major, minor and trace elements in pool solutions vary widely. A comparison of the geochemical compositions of host rocks and solutions indicates that leaching from rocks is not the only source of chemicals in thermal solutions. Geophysical studies reveal the inner structure of thermal fields, which reflect the shapes of the underground reservoirs and feed channels. Using geophysical methods (electrical resistivity tomography and frequency domain investigations), it was shown that the vertical structure and complex geochemical zonation of the feed channels leads to a high contrast in the compositions of the mud solutions. These findings answer questions about the origin and composition of surface manifestations. To elucidate the mechanisms of solution formation, an attempt was made to describe the magmatic fluid evolution and the resulting mixing of waters by physical and mathematical models. The model illustrates fluid migration from a magma chamber to the surface. It is shown that the formation of brines corresponding to the mud pool composition is possible during secondary boiling.

  4. Geochemical factors affecting radionuclide transport through near and far fields at a Low-Level Waste Disposal Site

    International Nuclear Information System (INIS)

    Kaplan, D.I.; Seme, R.J.; Piepkho, M.G.

    1995-03-01

    The concentration of low-level waste (LLW) contaminants in groundwater is determined by the amount of contaminant present in the solid waste, rate of release from the waste and surrounding barriers, and a number of geochemical processes including adsorption, desorption, diffusion, precipitation, and dissolution. To accurately predict radionuclide transport through the subsurface, it is essential that the important geochemical processes affecting radionuclide transport be identified and, perhaps more importantly, accurately quantified and described in a mathematically defensible manner

  5. Geochemical Interactions and Viral-Prokaryote Relationships in Freshwater Environments

    Science.gov (United States)

    Kyle, J. E.; Ferris, G.

    2009-05-01

    Viral and prokaryotic abundances were surveyed throughout southern Ontario aquatic habitats to determine relationships with geochemical parameters in the natural environment. Surface water samples were collected from acid mine drainage in summer of 2007 and 2008 and from circum-neutral pH environments in October to November 2008. Site determination was based on collecting samples from various aquatic habitats (acid mine drainage, lakes, rivers, tributaries, wetlands) with differing bedrock geology (limestone and shale dominated vs granitic Canadian Shield) to obtain a range of geochemical conditions. At each site, measurements of temperature, pH, and Eh were conducted. Samples collected for microbial counts and electron imaging were preserved to a final concentration of 2.5 % (v/v) glutaraldehyde. Additional sample were filtered into 60 mL nalgene bottles and amber EPA certified 40 mL glass vials to determine chemical constituents and dissolved organic carbon (DOC), respectively. Water was also collected to determine additional physiochemical parameters (dissolved total iron, ferric iron, nitrate, sulfate, phosphate, alkalinity, and turbidity). All samples were stored at 4 °C until analysis. Viral and prokaryotic abundance was determined by staining samples with SYBR Green I and examining with a epifluorescence microscope under blue excitation. Multiple regression analysis using stepwise backwards regression and general linear models revealed that viral abundance was the most influential predictor of prokaryotic abundance. Additional predictors include pH, sulfate, phosphate, and magnesium. The strength of the model was very strong with 90 % of the variability explained (R2 = 0.90, p < 0.007). This is the first report, to our knowledge, of viruses exhibiting such strong controls over prokaryotic abundance in the natural environment. All relationships are positively correlated with the exception of Mg, which is negatively correlated. Iron was also noted as a

  6. Experimental insights into geochemical changes in hydraulically fractured Marcellus Shale

    International Nuclear Information System (INIS)

    Marcon, Virginia; Joseph, Craig; Carter, Kimberly E.; Hedges, Sheila W.; Lopano, Christina L.; Guthrie, George D.; Hakala, J. Alexandra

    2017-01-01

    dissolution and secondary precipitation is observed in the presence of frac chemicals. • Organic acid, benzene and toluene concentrations increased in the experiment with frac chemicals. • SI for anhydrite depended on the redox conditions applied during geochemical modeling. • Calculations including organic acids decreased SI for barite and increased SI for smectite and carbonates.

  7. Drowning in Geochemical Data: The Good, the bad, and the Ugly

    Science.gov (United States)

    Hofmann, A. W.; Goldstein, S. L.

    2008-12-01

    , reservoir probably hidden near the base of the mantle. Among the most important changes triggered by the new databases are the following: (1) Driven by the database community, the standards required for reporting geochemical data in publications are changing in fundamental ways. Whereas it was common practice, especially in high-profile journals, to treat the data supporting the claims made in the published articles as relatively unimportant technical details, journal editors now require much more careful geochemical data reporting that includes complete data in numerical rather than graphical representation, information on sample locations, analytical methods, and uncertainty estimates. (2) Given the ever-increasing production rate of geochemical data, comprehensive use of geochemical data without relational databases is, or will soon be, impossible.

  8. Geochemical sensitivity analysis: Identification of important geochemical parameters for performance assessment studies

    International Nuclear Information System (INIS)

    Siegel, M.; Guzowski, R.; Rechard, R.; Erickson, K.

    1986-01-01

    The EPA Standard for geologic disposal of high level waste requires demonstration that the cumulative discharge of individual radioisotopes over a 10,000 year period at points 5 kilometers from the engineered barrier system will not exceed the limits prescribed in 40 CFR Part 191. The roles of the waste package, engineered facility, hydrogeology and geochemical processes in limiting radionuclide releases all must be considered in calculations designed to assess compliance of candidate repositories with the EPA Standard. In this talk, they will discuss the geochemical requirements of calculations used in these compliance assessments. In addition, they will describe the complementary roles of (1) simple models designed to bound the radionuclide discharge over the widest reasonable range of geochemical conditions and scenarios and (2) detailed geochemical models which can provide insights into the actual behavior of the radionuclides in the ground water. Finally, they will discuss development of sensitivity/uncertainty techniques designed to identify important site-specific geochemical parameters and processes using data from a basalt formation

  9. Basic concepts and formulations for isotope geochemical modelling of groundwater systems

    International Nuclear Information System (INIS)

    Kalin, R.M.

    1996-01-01

    This chapter describes the basic chemical principles and methodologies for geochemical models and their use in the field of isotope hydrology. Examples of calculation procedures are given on actual field data. Summary information on available PC software for geochemical modeling is included. The specific software, NETPATH, which can be used for chemical speciation, mass balance and isotope balance along a flow path in groundwater systems, is discussed at some length with an illustrative example of its application to field data. (author). Refs, 14 figs, 15 tabs

  10. Basic concepts and formulations for isotope geochemical modelling of groundwater systems

    Energy Technology Data Exchange (ETDEWEB)

    Kalin, R M [The Queen` s University, Belfast, Northern Ireland (United Kingdom). Dept. of Civil Engineering

    1996-10-01

    This chapter describes the basic chemical principles and methodologies for geochemical models and their use in the field of isotope hydrology. Examples of calculation procedures are given on actual field data. Summary information on available PC software for geochemical modeling is included. The specific software, NETPATH, which can be used for chemical speciation, mass balance and isotope balance along a flow path in groundwater systems, is discussed at some length with an illustrative example of its application to field data. (author). Refs, 14 figs, 15 tabs.

  11. Geochemical patterns in soils of the karst region, Croatia

    Science.gov (United States)

    Prohic, E.; Hausberger, G.; Davis, J.C.

    1997-01-01

    Soil samples were collected at 420 locations in a 5-km grid pattern in the Istria and Gorski Kotar areas of Croatia, and on the Croatian islands of Cres, Rab and Krk, in order to relate geochemical variation in the soils to underlying differences in geology, bedrock lithology, soil type, environment and natural versus anthropogenic influences. Specific objectives included assessment of possible agricultural and industrial sources of contamination, especially from airborne effluent emitted by a local power plant. The study also tested the adequacy of a fixed-depth soil sampling procedure developed for meager karstic soils. Although 40 geochemical variables were analyzed, only 15 elements and 5 radionuclides are common to all the sample locations. These elements can be divided into three groups: (1) those of mostly anthropogenic origin -Pb, V, Cu and Cr; (2) those of mixed origin - radionuclides and Zn; and (3) those of mostly geogene origin -Ba, Sr, Ti, Al, Na, Ca, Mg, Fe, Mn, Ni and Co. Variation in Pb shows a strong correlation with the pattern of road traffic in Istria. The distributions of Ca, Na and Mg in the flysch basins of southern Istria and Slovenia are clearly distinguishable from the distributions of these elements in the surrounding carbonate terrains, a consequence of differences in bedrock permeability, type of drainage and pH. The spatial pattern of Cs from the Chernobyl nuclear power plant accident reflects almost exclusively the precipitation in Istria during the days immediately after the explosion. ?? 1997 Elsevier Science B.V.

  12. Geochemical factors in borehole-shaft plug longevity

    International Nuclear Information System (INIS)

    Roy, D.M.

    1981-01-01

    Geochemical investigations that address factors controlling the longevity of repository sealing materials in a geochemical environment are discussed. Studies are being made of cement-based materials as major candidates for seals for borehole plugging, and shaft and tunnel sealing in certain potential repository environments. Factors controlling the extent of attainment of equilibrium of the plug components with time and the rate of approach to a state of stable equilibrium of the plug component chemical subsystem within the total system are discussed. The effect of these factors on changes in physical, mechanical and thermal properties of a seal system, and the consequent effectiveness of the seal in preventing transport of radioactive waste species are the dominant features to be determined. Laboratory experiments on the effects of anticipated temperature, pressure, and environmental factors (including chemical composition and specific rock type) are described. Thermodynamic studies are used to determine the potentially stable reaction products under conditions similar to those anticipated for the repository boreholes, shafts, and tunnels during and after the operating stage. Multitemperature reaction series are studied, and reaction kinetics are investigated for the purpose of predicting the course of likely reactions. Detailed studies of permeability, diffusion, and interfacial properties and chemical and microphase characterization of the products of experiments are carried out. Characterization studies of old and ancient cements, mortars, and concretes and prototype man-made seal materials are performed to further assess the factors associated with longevity

  13. Comparative study of geological, hydrological, and geophysical borehole investigations

    International Nuclear Information System (INIS)

    Magnusson, K.A.; Duran, O.

    1984-09-01

    The understanding of the permeability of the bedrock can be improved by supplementing the results of the water injection tests with information from core mapping, TB-inspection and borehole geophysics. The comparison between different borehole investigations encompasses core mapping, TV-inspection and various geophysical bore hole measurements. The study includes data from two different study areas, namely Kraakemaala and Finnsjoen. In these two areas, extensive geological, hydrological and geophysical investigation have been carried out. The fractures and microfractures in crystalline rock constitute the main transport paths for both groundwater and electric currents. They will therefore govern both the permeability and the resistivity of the rock. In order to get a better understanding of the influence of fractures on permeability and resistivity, a detailed comparison has been made between the hydraulic conductivity, respectively, and the character of fractures in the core and the borehole wall. The fractures show very large variations in hydraulic conductivity. Microfractures and most of the thin fractures have no measurable hydraulic conductivity (in this case -9 m s -1 ), while test sections which contain a single isloated fracture can have no measurable, to rather high hydraulic conductivities (> 10 -7 m s -1 ). Wide fracture zones often have hydraulic conductivities which vary from very low (less than 2 x 10 -9 m s -1 ) to high values (10 -5 m s -1 ). This indicates that the hydraulic conductivity is governed by a few discrete fractures. The resistivity shows a continous variation in the range 1,000- 100,000 ohm-m and a relatively poor correlation with hydraulic conductivities. The observed difference is considered to the effect of restriction of water flow on a few channels, while electric surface condition, i.e. current transport through thin water films, makes current transport possible through fractures with very small aperatures. (Author)

  14. Geophysical Investigation of a Thermokarst Lake Talik in Continuous Permafrost

    Science.gov (United States)

    Creighton, A.; Parsekian, A.; Arp, C. D.; Jones, B. M.; Babcock, E.; Bondurant, A. C.

    2016-12-01

    On the Arctic Coastal Plain (ACP) of northern Alaska, shallow thermokarst lakes cover up to 25% of the landscape. These lakes occupy depressions created by the subsidence of thawed, ice-rich permafrost. Areas of unfrozen sediment, or taliks, can form under lakes that have a mean annual bottom temperature greater than 0°C. The geometry of these taliks, as well as the processes that create them, are important for understanding interactions between surface water, groundwater, and carbon cycling. Non-invasive geophysical methods are a useful means to study talik sediments as borehole studies yield few data points, and the contrast between unfrozen and frozen sediments is an ideal geophysical target. To study talik configuration associated with an actively expanding thermokarst lake, we conducted a geophysical transect across Peatball Lake. This lake has an estimated initiation age of 1400 calendar years BP. Over the past 60 years, lake surface area has increased through thermal and mechanical shoreline erosion. A talik of previously unknown thickness likely exists below Peatball Lake. We conducted a transect of transient electromagnetic soundings across the lake extending into the surrounding terrestrial environment. Since permafrost has relatively high resistivity compared to talik sediments, the interpreted electrical structure of the subsurface likely reflects talik geometry. We also conducted nuclear magnetic resonance soundings at representative locations along the transect. These measurements can provide data on sub-lake sediment properties including water content. Together, these measurements resolve the talik structure across the lake transect and showed evidence of varying talik thicknesses from the lake edge to center. These is no evidence of a talik at the terrestrial control sites. These results can help constrain talik development models and thus provide insight into Arctic and permafrost processes in the face of a changing climate.

  15. Improving Discoverability of Geophysical Data using Location Based Services

    Science.gov (United States)

    Morrison, D.; Barnes, R. J.; Potter, M.; Nylund, S. R.; Patrone, D.; Weiss, M.; Talaat, E. R.; Sarris, T. E.; Smith, D.

    2014-12-01

    The great promise of Virtual Observatories is the ability to perform complex search operations across the metadata of a large variety of different data sets. This allows the researcher to isolate and select the relevant measurements for their topic of study. The Virtual ITM Observatory (VITMO) has many diverse geophysical datasets that cover a large temporal and spatial range that present a unique search problem. VITMO provides many methods by which the user can search for and select data of interest including restricting selections based on geophysical conditions (solar wind speed, Kp, etc) as well as finding those datasets that overlap in time. One of the key challenges in improving discoverability is the ability to identify portions of datasets that overlap in time and in location. The difficulty is that location data is not contained in the metadata for datasets produced by satellites and would be extremely large in volume if it were available, making searching for overlapping data very time consuming. To solve this problem we have developed a series of light-weight web services that can provide a new data search capability for VITMO and others. The services consist of a database of spacecraft ephemerides and instrument fields of view; an overlap calculator to find times when the fields of view of different instruments intersect; and a magnetic field line tracing service that maps in situ and ground based measurements to the equatorial plane in magnetic coordinates for a number of field models and geophysical conditions. These services run in real-time when the user queries for data. They will allow the non-specialist user to select data that they were previously unable to locate, opening up analysis opportunities beyond the instrument teams and specialists, making it easier for future students who come into the field.

  16. Transport in zonal flows in analogous geophysical and plasma systems

    Science.gov (United States)

    del-Castillo-Negrete, Diego

    1999-11-01

    Zonal flows occur naturally in the oceans and the atmosphere of planets. Important examples include the zonal flows in Jupiter, the stratospheric polar jet in Antarctica, and oceanic jets like the Gulf Stream. These zonal flows create transport barriers that have a crucial influence on mixing and confinement (e.g. the ozone depletion in Antarctica). Zonal flows also give rise to long-lasting vortices (e.g. the Jupiter red spot) by shear instability. Because of this, the formation and stability of zonal flows and their role on transport have been problems of great interest in geophysical fluid dynamics. On the other hand, zonal flows have also been observed in fusion plasmas and their impact on the reduction of transport has been widely recognized. Based on the well-known analogy between Rossby waves in quasigeostrophic flows and drift waves in magnetically confined plasmas, I will discuss the relevance to fusion plasmas of models and experiments recently developed in geophysical fluid dynamics. Also, the potential application of plasma physics ideas to geophysical flows will be discussed. The role of shear in the suppression of transport and the effect of zonal flows on the statistics of transport will be studied using simplified models. It will be shown how zonal flows induce large particle displacements that can be characterized as Lévy flights, and that the trapping effect of vortices combined with the zonal flows gives rise to anomalous diffusion and Lévy (non-Gaussian) statistics. The models will be compared with laboratory experiments and with atmospheric and oceanographic qualitative observations.

  17. Geophysical Methods for Non-Destructive Testing in Civil Engineering

    Science.gov (United States)

    Niederleithinger, E.

    2013-12-01

    Many non-destructive testing (NDT) methods for civil engineering (e. g. ultrasonics, radar) are similar to geophysical techniques. They just differ in scale, material under investigation and vocabulary used. In spite of the fact that the same principles of physics and mathematics apply to both fields, exchange has been limited in the past. But since a few years more and more geophysical knowledge is used in civil engineering. One of the focal points in research is to improve ultrasonic testing of concrete to be able to image the inside even of large, complex structures and to detect any deterioration as early as possible. One of the main issues is the heterogeneity of concrete, including aggregates, reinforcement, cracks and many other features. Our current research focuses on three points. One is the application of state of the art geophysical migration techniques as Reverse Time Migration (RTM) to image vertical faces or the backside of voids and ducts in thick concrete structures, which isn't possible with conventional techniques used in NDT. Second, we have started to use seismic interferometric techniques to interpolate ultrasonic traces, which can't be measured directly for technical reasons. Third, we are using coda wave interferometry to detect concrete degradation due to load, fatigue, temperature or other influences as early as possible. Practical examples of the application of these techniques are given and potential future research directions will be discussed. It will be shown, how a subset of these techniques can be used for innovative monitoring systems for civil infrastructure. Imaging the interior of a concrete body by ultrasonics and reverse time migration(simulated data).

  18. Characterisation of the heterogeneity of karst using electrical geophysics - applications in SW China

    Science.gov (United States)

    Binley, A. M.; Cheng, Q.; Tao, M.; Chen, X.

    2017-12-01

    The southwest China karst region is one of the largest globally continuous karst areas. The great (structural, hydrological and geochemical) complexity of karstic environments and their rapidly evolving nature make them extremely vulnerable to natural and anthropogenic processes/activities. Characterising the location and properties of structures within the karst critical zone, and understanding how the landform is evolving is essential for the mitigation and adaption to locally- and globally-driven changes. Because of the specific nature of karst geology and geomorphology in the humid tropics and subtropics, spatial heterogeneity is high, evidenced by specific landforms features. Such heterogeneity leads to a high dynamic variability of hydrological processes in space and time, along with a complex exchange of surface water and groundwater. Investigating karst hydrogeological features is extremely challenging because of the three-dimensional nature of the system. Observations from boreholes can vary significantly over several metres, making conventional aquifer investigative methods limited. Geophysical methods have emerged as potentially powerful tools for hydrogeological investigations. Geophysical surveys can help to obtain more insight into the complex conduit networks and depth of weathering, both of which can provide quantitative information about the hydrological and hydrochemical dynamics of the system, in addition to providing a better understanding of how critical zone structures have been established and how the landscape is evolving. We present here results from recent geophysical field campaigns in SW China. We illustrate the effectiveness of electrical methods for mapping soil infil in epikarst and report results from field-based investigations along hillslope and valley transects. Our results reveal distinct zones of relatively high electrical conductivity to depths of tens of metres, which we attribute to localised increased fracture density. We

  19. Research needs for coupling geochemical and flow models for nuclear waste isolation

    International Nuclear Information System (INIS)

    Pearson, F.J. Jr.

    1985-01-01

    An overview of coupling geochemical and flow models for nuclear waste disposal is presented and research needs are discussed. Topics considered include, chemical effects on flow, fluid and rock properties, pressure effects, water-rock equilibria, and reaction kinetics. 25 references

  20. Proceedings of a workshop on geophysical and related geoscientific research at Chalk River, Ontario

    International Nuclear Information System (INIS)

    Thomas, M.D.; Dixon, D.F.

    1989-10-01

    A large part of the Canadian Nuclear Fuel Waste Management Program is geoscience research and development aimed at obtaining information to quantify the transport of radionuclides through the geosphere and at determining the geotechnical properties required for disposal vault design. The geosphere at potential disposal sites is characterized in part by the use of remote sensing (geophysical) methods. In 1977 public concern about the disposal of radioactive waste resulted in field work being restricted to the site of Chalk River Nuclear Laboratories, which was used to develop, evaluate and compare various techniques in order to optimize the methods for obtaining geoscience information. Methods tested at Chalk River are to be applied at other research sites. Most investigations have been carried out around Maskinonge Lake, using about thirty boreholes sink into bedrock. The boreholes provide subsurface geological information that can be used as a reference to compare the responses of various geophysical methods and equipment. Regional studies, including airborne geophysical surveys, have also been conducted. The 25 papers presented at this workshop provide comprehensive documentation of the most significant results of geophysical studies. The workshop also provided an evaluation of geophysical techniques and their utility to the Nuclear Fuel Waste Management Program

  1. Geophysical contribution for Folha Patos (PI, Brazil)

    International Nuclear Information System (INIS)

    Rodrigues, J.C.; Mota, A.C.; Metelo, M.J.; Vasconcelos, R.M. de

    1990-01-01

    As a part of PLGB (Brazilian Geologic reconnaissance program), executed in 1986-1989 period by Companhia de Pesquisa de Recursos Minerais - CPRM to the Departamento Nacional da Producao Mineral - DNPM, geophysical studies were carried out in the Patos Quadrangle (SB. 24-Y-C-V). Gravimetric, magnetometric and scintillometric methods were performed over selected profiles, and the interpretation of aerial gamma-spectrometric maps (total, potassium, uranium and thorium channels) were integrated with geologic data. Computer programs Magpoly and Gravpoly were utilized in modelling geophysical surface data. Results of theses studies were auxiliary to the geological mapping of that area, specially in localizing lithological contacts and differentiations, tectonic structures, and revealed the structural compartimentation among crustal segments with distinct metamorphic grades. (author)

  2. Geophysical and atmospheric evolution of habitable planets.

    Science.gov (United States)

    Lammer, Helmut; Selsis, Frank; Chassefière, Eric; Breuer, Doris; Griessmeier, Jean-Mathias; Kulikov, Yuri N; Erkaev, Nikolai V; Khodachenko, Maxim L; Biernat, Helfried K; Leblanc, Francois; Kallio, Esa; Lundin, Richard; Westall, Frances; Bauer, Siegfried J; Beichman, Charles; Danchi, William; Eiroa, Carlos; Fridlund, Malcolm; Gröller, Hannes; Hanslmeier, Arnold; Hausleitner, Walter; Henning, Thomas; Herbst, Tom; Kaltenegger, Lisa; Léger, Alain; Leitzinger, Martin; Lichtenegger, Herbert I M; Liseau, René; Lunine, Jonathan; Motschmann, Uwe; Odert, Petra; Paresce, Francesco; Parnell, John; Penny, Alan; Quirrenbach, Andreas; Rauer, Heike; Röttgering, Huub; Schneider, Jean; Spohn, Tilman; Stadelmann, Anja; Stangl, Günter; Stam, Daphne; Tinetti, Giovanna; White, Glenn J

    2010-01-01

    The evolution of Earth-like habitable planets is a complex process that depends on the geodynamical and geophysical environments. In particular, it is necessary that plate tectonics remain active over billions of years. These geophysically active environments are strongly coupled to a planet's host star parameters, such as mass, luminosity and activity, orbit location of the habitable zone, and the planet's initial water inventory. Depending on the host star's radiation and particle flux evolution, the composition in the thermosphere, and the availability of an active magnetic dynamo, the atmospheres of Earth-like planets within their habitable zones are differently affected due to thermal and nonthermal escape processes. For some planets, strong atmospheric escape could even effect the stability of the atmosphere.

  3. Geophysical investigation, Salmon Site, Lamar County, Mississippi

    International Nuclear Information System (INIS)

    1995-02-01

    Geophysical surveys were conducted in 1992 and 1993 on 21 sites at the Salmon Site (SS) located in Lamar County, Mississippi. The studies are part of the Remedial Investigation/Feasibility Study (RI/FS) being conducted by IT Corporation for the U.S. Department of Energy (DOE). During the 1960s, two nuclear devices and two chemical tests were detonated 826 meters (in) (2710 feet [ft]) below the ground surface in the salt dome underlying the SS. These tests were part of the Vela Uniform Program conducted to improve the United States capability to detect, identify, and locate underground nuclear detonations. The RI/FS is being conducted to determine if any contamination is migrating from the underground shot cavity in the salt dome and if there is any residual contamination in the near surface mud and debris disposal pits used during the testing activities. The objective of the surface geophysical surveys was to locate buried debris, disposal pits, and abandoned mud pits that may be present at the site. This information will then be used to identify the locations for test pits, cone penetrometer tests, and drill hole/monitor well installation. The disposal pits were used during the operation of the test site in the 1960s. Vertical magnetic gradient (magnetic gradient), electromagnetic (EM) conductivity, and ground-penetrating radar (GPR) surveys were used to accomplish these objectives. A description of the equipment used and a theoretical discussion of the geophysical methods are presented Appendix A. Because of the large number of figures relative to the number of pages of text, the geophysical grid-location maps, the contour maps of the magnetic-gradient data, the contour maps of the EM conductivity data, and the GPR traverse location maps are located in Appendix B, Tabs I through 22. In addition, selected GPR records are located in Appendix C

  4. Monitoring Global Geophysical Fluids by Space Geodesy

    Science.gov (United States)

    Chao, Benjamin F.; Dehant, V.; Gross, R. S.; Ray, R. D.; Salstein, D. A.; Watkins, M.

    1999-01-01

    Since its establishment on 1/1/1998 by the International Earth Rotation Service, the Coordinating Center for Monitoring Global Geophysical Fluids (MGGF) and its seven Special Bureaus have engaged in an effort to support and facilitate the understanding of the geophysical fluids in global geodynamics research. Mass transports in the atmosphere-hydrosphere-solid Earth-core system (the "global geophysical fluids") will cause the following geodynamic effects on a broad time scale: (1) variations in the solid Earth's rotation (in length-of-day and polar motion/nutation) via the conservation of angular momentum and effected by torques at the fluid-solid Earth interface; (2) changes in the global gravitational field according to Newton's gravitational law; and (3) motion in the center of mass of the solid Earth relative to that of the whole Earth ("geocenter") via the conservation of linear momentum. These minute signals have become observable by space geodetic techniques, primarily VLBI, SLR, GPS, and DORIS, with ever increasing precision/accuracy and temporal/spatial resolution. Each of the seven Special Bureaus within MGGF is responsible for calculations related to a specific Earth component or aspect -- Atmosphere, Ocean, Hydrology, Ocean Tides, Mantle, Core, and Gravity/Geocenter. Angular momenta and torques, gravitational coefficients, and geocenter shift will be computed for geophysical fluids based on global observational data, and from state-of-the-art models, some of which assimilate such data. The computed quantities, algorithm and data formats are standardized. The results are archived and made available to the scientific research community. This paper reports the status of the MGGF activities and current results.

  5. Development of geophysical data management system

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Tai-Sup; Lee, Sang-Kyu; Gu, Sung-Bon [Korea Institute of Geology Mining and Materials, Taejon (KR)] (and others)

    1999-12-01

    (1) Development of a complete geophysical database system under C/S environment for data management. (2) Development of database system for the general user, who has not special knowledge of database, under the Internet environment. (3) Operation of the Web service for the general user. (4) Development of the stand-alone database system for a small-scale research group such as college and engineering consultant firms. (author). 15 refs.

  6. Application of geophysical methods for fracture characterization

    International Nuclear Information System (INIS)

    Lee, K.H.; Majer, E.L.; McEvilly, T.V.; California Univ., Berkeley, CA; Morrison, H.F.; California Univ., Berkeley, CA

    1990-01-01

    One of the most crucial needs in the design and implementation of an underground waste isolation facility is a reliable method for the detection and characterization of fractures in zones away from boreholes or subsurface workings. Geophysical methods may represent a solution to this problem. If fractures represent anomalies in the elastic properties or conductive properties of the rocks, then the seismic and electrical techniques may be useful in detecting and characterizing fracture properties. 7 refs., 3 figs

  7. Airborne geophysics in Australia: the government contribution

    International Nuclear Information System (INIS)

    Denham, D.

    1997-01-01

    Airborne geophysical data sets provide important cost-effective information for resource exploration and land management. Improved techniques, developed recently, now enable high-resolution aeromagnetic and gamma-ray surveys to be used extensively by the resource industries to improve the cost effectiveness of exploration and by governments to encourage resource development and sustainable management of natural resources. Although airborne geophysical techniques have been used extensively and are now used almost routinely by mineral explorers, it is only in the last few years that governments have been involved as major players in the acquisition of data. The exploration industry pioneered the imaging of high-resolution airborne geophysical data sets in the early 1980s and, at the same time, the Northern Territory Government started a modest program of flying the Northern Territory, at 500 m flight-line spacing, to attract mineral exploration. After the start of the National Geoscience Mapping Accord in 1990, the then BMR and its State/Territory counterparts used the new high-resolution data as an essential ingredient to underpin mapping programs. These new data sets proved so valuable that, starting in 1992/93, the annual expenditure by the Commonwealth and States/Northern Territory increased from roughly $2 million per year to a massive $10 million per year. These investments by governments, although unlikely to be permanently sustainable, have been made to encourage and expand exploration activity by providing new high-quality data sets in industry at very low cost. There are now approximately 11 million line-km of airborne geophysical data available in databases held by the Commonwealth, States and Northern Territory. The results so far have seen a significant increase in exploration activity in States that have embarked on this course (e.g. South Australia and Victoria), and the information provided from these surveys is proving crucial to understanding the

  8. Geophysical logging of the Harwell boreholes

    International Nuclear Information System (INIS)

    Brightman, M.A.

    1983-08-01

    A comprehensive geophysical borehole logging survey was carried out on each of three deep boreholes drilled at the Harwell research site. KOALA and PETRA computer programs were used to analyse and interpret the logs to obtain continuous quantitative estimates of the geological and hydrogeological properties of the sequences penetrated at the Harwell site. Quantitative estimates of the mineral composition and porosity of the cores samples were made. (UK)

  9. Determination of the Geothermal Potential by Geophysical Investigations in the Karbinci-Tarinci Area, in the Vicinity of Shtip

    International Nuclear Information System (INIS)

    Petrov, Goshe; Panovska, Sanja; Delipetrov, Marjan; Dimov, Gjorgji; Jovanovski, Vlatko

    2005-01-01

    Geophysical methods used in the determination of geothermal potential by geophysical investigations in the Karbinci-Tarinci area included as follows: detailed reflective seismic scanning, geomagnetic profiling, geo electric probe and electromagnetic VLF prospecting. The site investigated consists of rocks of Precambrian, Mesozoic (Jurassic), Tertiary (Paleogene Neogene) and Quaternary age. From earlier investigations carried out in the wider vicinity and from investigations carried out by the present authors, one can expect occurrence geothermal water in the area. (Author)

  10. Russian Meteorological and Geophysical Rockets of New Generation

    Science.gov (United States)

    Yushkov, V.; Gvozdev, Yu.; Lykov, A.; Shershakov, V.; Ivanov, V.; Pozin, A.; Afanasenkov, A.; Savenkov, Yu.; Kuznetsov, V.

    2015-09-01

    To study the process in the middle and upper atmosphere, ionosphere and near-Earth space, as well as to monitor the geophysical environment in Russian Federal Service for Hydrology and Environmental Monitoring (ROSHYDROMET) the development of new generation of meteorological and geophysical rockets has been completed. The modern geophysical research rocket system MR-30 was created in Research and Production Association RPA "Typhoon". The basis of the complex MR-30 is a new geophysical sounding rocket MN-300 with solid propellant, Rocket launch takes place at an angle of 70º to 90º from the launcher, which is a farm with a guide rail type required for imparting initial rotation rocket. The Rocket is spin stabilized with a spin rate between 5 and 7 Hz. Launch weight is 1564 kg, and the mass of the payload of 50 to 150 kg. MR-300 is capable of lifting up to 300 km, while the area of dispersion points for booster falling is an ellipse with parameters 37x 60 km. The payload of the rocket MN-300 consists of two sections: a sealed, located below the instrument compartment, and not sealed, under the fairing. Block of scientific equipment is formed on the platform in a modular layout. This makes it possible to solve a wide range of tasks and conduct research and testing technologies using a unique environment of space, as well as to conduct technological experiments testing and research systems and spacecraft equipment. New Russian rocket system MERA (MEteorological Rocket for Atmospheric Research) belongs to so called "dart" technique that provide lifting of small scientific payload up to altitude 100 km and descending with parachute. It was developed at Central Aerological Observatory jointly with State Unitary Enterprise Instrument Design Bureau. The booster provides a very rapid acceleration to about Mach 5. After the burning phase of the buster the dart is separated and continues ballistic flight for about 2 minutes. The dart carries the instrument payload+ parachute

  11. Podoconiosis - non-filarial geochemical elephantiasis - a neglected tropical disease?

    Science.gov (United States)

    Nenoff, Pietro; Simon, Jan Christoph; Muylowa, Grace K; Davey, Gail

    2010-01-01

    Podoconiosis or mossy foot is a form of non-filarial lymphedema. This geochemical elephantiasis is a disabling condition caused by the passage of microparticles of silica and aluminum silicates through the skin of people walking barefoot in areas with a high content of soil of volcanic origin. Podoconiosis is widespread in tropical Africa, Central America and North India, yet it remains a neglected and under-researched condition. The disabling effects of podoconiosis cause great hardship to patients. It adversely affects the economic (reduced productivity and absenteeism), social (marriage, education, etc.) and psychological (social stigma) well-being of those affected. Podoconiosis can be prevented; the main primary preventive measure is protective footwear. Secondary measures include a strict hygiene regimen and compression therapy, which can reverse initial lesions. Tertiary approaches include surgical management, such as shaving operations to reduce hyperplastic and verrucous elephantiasis.

  12. Borehole geophysics in nuclear power plant siting

    International Nuclear Information System (INIS)

    Crosby, J.W.; Scott, J.D.

    1979-01-01

    Miniaturized borehole geophysical equipment designed for use in ground-water investigations can be adapted to investigations of nuclear power plant sites. This equipment has proved to be of value in preliminary and comprehensive studies of interior basins where thick sequences of Quaternary clastic sediment, occasionally with associated volcanic rocks, pose problems of stratigraphic correlation. The unconsolidated nature of the deposits generally requires that exploratory holes be cased, which ordinarily restricts the borehole geophysical studies to the radiation functions--natural gamma, gamma-gamma, neutron-gamma, and neutron-epithermal neutron logs. Although a single log response may be dominant in a given area, correlations derive from consideration of all log responses as a composite group. Because major correlations usually are based upon subtle differences in the physical properties of the penetrated sediment, high-resolution logging procedures are employed with some sacrifice of the quantitative perameters important to petroleum technology. All geophysical field data are recorded as hard copy and as digital information on punched paper tape

  13. Borehole geophysics in nuclear power plant siting

    International Nuclear Information System (INIS)

    Crosby, J.W.; Scott, J.D.

    1979-01-01

    Miniaturized borehole geophysical equipment designed for use in ground-water investigations can be adapted to investigations of nuclear power plant sites. This equipment has proved to be of value in preliminary and comprehensive studies of interior basins where thick sequences of Quaternary clastic sediment, occasionally with associated volcanic rocks, pose problems of stratigraphic correlation. The unconsolidated nature of the deposits generally requires that exploratory holes be cased, which ordinarily restricts the borehole geophysical studies to the radiation functions--natural gamma, gamma-gamma, neutron-gamma, and neutron-epithermal neutron logs. Although a single log response may be dominant in a given area, correlations derive from consideration of all log responses as a composite group. Because major correlations usually are based upon subtle differences in the physical properties of the penetrated sediment, high-resolution logging procedures are employed with some sacrifice of the quantitative parameters important to petroleum technology. All geophysical field data are recorded as hard copy and as digital information on punched paper tape. Digital data are subsequently computer processed and plotted to scales that enhance the stratigraphic data being correlated. Retention of the data in analog format permits rapid review, whereas computer plotting allows playback and detailed examination of log sections and sequences that may be attenuated on hard copy because of the logarithmic nature of the response to the physical property being examined

  14. Investigations into near-real-time surveying for geophysical data collection using an autonomous ground vehicle

    Science.gov (United States)

    Phelps, Geoffrey A.; Ippolito, C.; Lee, R.; Spritzer, R.; Yeh, Y.

    2014-01-01

    The U.S. Geological Survey and the National Aeronautics and Space Administration are cooperatively investigating the utility of unmanned vehicles for near-real-time autonomous surveys of geophysical data collection. Initially focused on unmanned ground vehicle collection of magnetic data, this cooperative effort has brought unmanned surveying, precision guidance, near-real-time communication, on-the-fly data processing, and near-real-time data interpretation into the realm of ground geophysical surveying, all of which offer advantages over current methods of manned collection of ground magnetic data. An unmanned ground vehicle mission has demonstrated that these vehicles can successfully complete missions to collect geophysical data, and add advantages in data collection, processing, and interpretation. We view the current experiment as an initial phase in further unmanned vehicle data-collection missions, including aerial surveying.

  15. Computer-based system for processing geophysical data obtained from boreholes

    International Nuclear Information System (INIS)

    Richter, J.M.

    1982-01-01

    A diverse set of computer programs has been developed at the Lawrence Livermore National Laboratory (LLNL) to process geophysical data obtained from boreholes. These programs support such services as digitizing analog records, reading and processing raw data, cataloging and storing processed data, retrieving selected data for analysis, and generating data plots on several different devices. A variety of geophysical data types are accommodated, including both wireline logs and laboratory analyses of downhole samples. Many processing tasks are handled by means of a single, flexible, general-purpose data-manipulation program. Separate programs are available for processing data from density, gravity, velocity, and epithermal neutron logs

  16. Geophysical Surveys of a Known Karst Feature, Oak Ridge Y-12 Plant, Oak Ridge, Tennessee

    International Nuclear Information System (INIS)

    Doll, W.E.; Nyquist, J.E.; Carpenter, P.J.; Kaufmann, R.D.; Carr, B.J.

    1998-01-01

    Geophysical data were acquired at a site on the Oak Ridge Reservation, Tennessee to determine the characteristics of a mud-filled void and to evaluate the effectiveness of a suite of geophysical methods at the site. Methods that were used included microgravity, electrical resistivity, and seismic refraction. Both microgravity and resistivity were able to detect the void as well as overlying structural features. The seismic data provide bedrock depth control for the other two methods, and show other effects that are caused by the void

  17. Connections between borehole geophysical parameters of the quality of cement raw materials

    International Nuclear Information System (INIS)

    Szabo, L.; Illes, A.

    1978-01-01

    The raw materials for the cement industry are prospected - according to the recommendations of national authorities - by geophysical methods, too. These include not the determination of the deposit boundary, but also an estimation of the quality of limestone and clay from the point of cement manufacture. No forerunners of such tests exist, so new methods were elaborated. After 12 years of site tests it was found that the correlation between laboratory quality tests and certain geophysical parameters of clay deposits is fair but less close in case of limestone deposits. (author)

  18. Some results of NURE uranium geochemical studies

    International Nuclear Information System (INIS)

    Price, V. Jr.

    1979-01-01

    Some technical developments of the National Uranium Resource Evaluation Program which are of general application in geochemical exploration are being studied. Results of stream water and suspended and bottom sediment analyses are compared for an area near Williamsport, Pennsylvania. Variations of uranium content of water samples with time in the North Carolina Piedmont are seen to correlate with rainfall. Ground water samples from coastal and piedmont areas were analyzed for helium. All media sampled provide useful information when properly analyzed and interpreted as part of a total geological analysis of an area

  19. Panay carborne radiometric and geochemical surveys

    International Nuclear Information System (INIS)

    Santos, G. Jr.

    1981-09-01

    A carborne radiometric survey and stream sediments collection were conducted in Panay and Guimaras Islands. An area in Nabas, Aklan, situated in the northwestern tip of Panay (Buruanga Peninsula) which indicated 2 to 3 times above background radioactivity was delineated. Uranium content in the stream sediment samples collected from Buruanga Peninsula was generally higher than those obtained in other parts of the island. Radioactivity measurements and uranium content in stream sediments were found to be within background levels. It is recommended that follow-up radiometric and geochemical surveys be undertaken in Buruanga Peninsula and additional stream sediments samples be collected in Panay to achieve better sampling density and coverage. (author)

  20. Landscape-geochemical factors of deposit formation

    International Nuclear Information System (INIS)

    Batulin, S.G.

    1980-01-01

    Effect of landscape-geochemical factors on hydrogenic formation of uranium ores is considered. The primary attention is paid to finding reasons for hydrogeochemical background increase in the regions of arid climate. Problems of uranium distribution in alluvial landscapes, hydrogeochemical regime of ground waters, reflecting the effect of waters of the zone of aeration are revealed. Chemical composition of porous solutions in the zone of aeration, as well as historical geochemindstry of landscape a its role from the view point of uranium solution formation in the arid zone are considered [ru

  1. DNA-based methods of geochemical prospecting

    Energy Technology Data Exchange (ETDEWEB)

    Ashby, Matthew [Mill Valley, CA

    2011-12-06

    The present invention relates to methods for performing surveys of the genetic diversity of a population. The invention also relates to methods for performing genetic analyses of a population. The invention further relates to methods for the creation of databases comprising the survey information and the databases created by these methods. The invention also relates to methods for analyzing the information to correlate the presence of nucleic acid markers with desired parameters in a sample. These methods have application in the fields of geochemical exploration, agriculture, bioremediation, environmental analysis, clinical microbiology, forensic science and medicine.

  2. Geochemical modelling. Pt.1, Pt.2

    International Nuclear Information System (INIS)

    Skytte Jensen, B.; Jensen, H.; Pearson, F.J.

    1992-01-01

    This work is carried out under cost-sharing contract with the European Atomic Energy Community in the framework of its fourth research programme on radioactive waste management and radioactive waste storage. This final report is subdivided into two parts. In the first part, JENSEN, a computer code for the computation of chemical equilibria in aqueous systems, describes the structure, function and use of a new geochemical computer program intended for PC's. The program, which is written in Turbo Pascal, version 4, is fundamentally similar to most other geochemical programs, but combines in one program several of the merits these programs have. The intention has been to make an advanced program, which also should be user friendly and fast, and to attain this several new algorithms have been developed and implemented. The program has a built-in database mainly based on the CHEMVAL compilation containing data for 395 soluble species and 149 minerals. The program can find equilibria in the presence of all or some of these soluble species, under conditions or fixed or floating pH and / or Redox potential. The program by itself eliminates a bad guess of a candidate for precipitation. In the present version, the program can identify which minerals and how much of them there will be formed when equilibrium is established. In the second part, LITTLE JOE, an expert system to support geochemical modelling, describes the construction of a minor expert system for use in the evaluation of analytical data for the composition of ground waters from limestone formation. Although the example given is rather limited in scope, the application of the expert system for the evaluation of the analytical data clearly demonstrates the mature expert knowledge imbedded in the system which is contrasted with the uncritical acceptance of analytical or theoretical data. With the overall neglect of ion-exchange and the formation of solid solutions in geochemical calculations, geochemistry is

  3. Investigating the temporal fluctuations in geoelectrical and geochemical signals jointly measured in a a seismic area of Southern Apennine chain (Italy)

    Energy Technology Data Exchange (ETDEWEB)

    Cuomo, V.; Di Bello, G. [Potenza Universita' della Basilicata, Potenza (Italy). Dipt. di Ingegneria e Fisica dell' Ambiente; Heinecke, J. [Saxon Academy of Sciences, Leipzig (Germany); Lapenna, V.; Piscitelli, S.; Telesca, L. [Consiglio Nazionale delle Ricerche, Ist. di Metodologie Avanzate di Analisi Ambientale, Tito Scalo, PZ (Italy); Martinelli, G. [Regione Emilia-Romagna, Servizio Cartografico, Bologna (Italy)

    2001-04-01

    In this work are analysed geoelectrical and geochemical time series jointly measured by means of a multiparametric automatic station close to an anomalous find emission in Val d'Agri (Basilicata, Southern Italy). In the investigated area some destructive seismic events occurred in past and recent years. Temporal fluctuations of the signals by spectral tools are investigated. Scaling behaviours in the power spectra of the time series recorded have been detected, they are typical fingerprints of fractional Brownian motions. The estimated values of the spectral indices reveal the presence of antipersistent behaviour in the time dynamics of all geoelectrical and geochemical data recorded. This work intends to improve the knowledge of the inner time dynamics of geophysical non-seismometric parameters.

  4. Investigating the temporal fluctuations in geoelectrical and geochemical signals jointly measured in a a seismic area of Southern Apennine chain (Italy)

    Energy Technology Data Exchange (ETDEWEB)

    Cuomo, V; Di Bello, G [Potenza Universita' della Basilicata, Potenza (Italy). Dipt. di Ingegneria e Fisica dell' Ambiente; Heinecke, J [Saxon Academy of Sciences, Leipzig (Germany); Lapenna, V; Piscitelli, S; Telesca, L [Consiglio Nazionale delle Ricerche, Ist. di Metodologie Avanzate di Analisi Ambientale, Tito Scalo, PZ (Italy); Martinelli, G [Regione Emilia-Romagna, Servizio Cartografico, Bologna (Italy)

    2001-04-01

    In this work are analysed geoelectrical and geochemical time series jointly measured by means of a multiparametric automatic station close to an anomalous find emission in Val d'Agri (Basilicata, Southern Italy). In the investigated area some destructive seismic events occurred in past and recent years. Temporal fluctuations of the signals by spectral tools are investigated. Scaling behaviours in the power spectra of the time series recorded have been detected, they are typical fingerprints of fractional Brownian motions. The estimated values of the spectral indices reveal the presence of antipersistent behaviour in the time dynamics of all geoelectrical and geochemical data recorded. This work intends to improve the knowledge of the inner time dynamics of geophysical non-seismometric parameters.

  5. The lithospheric structure beneath Ireland and surrounding areas from integrated geophysical-petrological modelling of magnetic and other geophysical data

    Science.gov (United States)

    Baykiev, E.; Guerri, M.; Fullea, J.

    2017-12-01

    The availability of unprecedented resolution aeromagnetic data in Ireland (Tellus project, http://www.tellus.ie/) in conjunction with new satellite magnetic data (e.g., ESÁs Swarm mission) has opened the possibility of detailed modelling of the Irish subsurface magnetic structure. A detailed knowledge of the magnetic characteristics (susceptibility, magnetite content) of the crust is relevant for a number of purposes, including geological mapping and mineral and geothermal energy prospection. In this work we model the magnetic structure of Ireland and surrounding areas using primarily aeromagnetic and satellite observations but also other geophysical data sets. To this aim we use a geophysical-petrological modelling tool (LitMod) in which key properties of rocks (i.e., density, electrical conductivity and seismic velocities) that can be inferred from geophysical data (gravity, seismic, EM) are self consistently determined based on the thermochemical conditions (using the software Perple_X). In contrast to the mantle, where thermodynamic equilibrium is prevalent, in the crust metastable conditions are dominant, i.e. rock properties may not be representative of the current, in situ, temperature and pressure conditions. Instead, the rock properties inferred from geophysical data may be reflecting the mineralogy stable at rock formation conditions. In addition, temperature plays a major role in the distribution of the long wavelength crustal magnetic anomalies. Magnetite retains its magnetic properties below its Curie temperature (585 ºC) and the depth of Curie's isotherm provides an estimate of the thickness of the magnetic crust. Hence, a precise knowledge of the crustal geotherm is required to consistently model crustal magnetic anomalies. In this work LitMod has been modified to account for metastable crustal lithology, to predict susceptibility in the areas below Curie's temperature, and to compute magnetic anomalies based on a magnetic tesseroid approach. The

  6. Geochemical evidences of magma dynamics at Campi Flegrei (Italy)

    Science.gov (United States)

    Caliro, S.; Chiodini, G.; Paonita, A.

    2014-05-01

    Campi Flegrei caldera, within the Neapolitan area of Italy, is potentially one of the most dangerous volcanoes in the world, and during the last decade it has shown clear signs of reactivation, marked by the onset of uplift and changes in the geochemistry of gas emissions. We describe a 30-year-long data set of the CO2-He-Ar-N2 compositions of fumarolic emissions from La Solfatara crater, which is located in the center of the caldera. The data display continuous decreases in both the N2/He and N2/CO2 ratios since 1985, paralleled by an increase in He/CO2. These variations cannot be explained by either processes of boiling/condensation in the local hydrothermal system or with changes in the mixing proportions between a magmatic vapor and hydrothermal fluids. We applied the magma degassing model of Nuccio and Paonita (2001, Earth Planet. Sci. Lett. 193, 467-481) using the most recent inert-gas solubilities in order to interpret these peculiar features in accordance with petrologic constraints derived from the ranges of the melt compositions and reservoir pressures at Campi Flegrei. The model simulations for mafic melts (trachybasalt and shoshonite) show a remarkably good agreement with the measured data. Both decompressive degassing of an ascending magma and mixing between magmatic fluids exsolved at various levels along the ascent path can explain the long-term geochemical changes. Recalling that (i) a sill-like reservoir of gases at a depth of 3-4 km seems to be the main source of ground inflation and (ii) there is petrologic and geophysical evidence for a reservoir of magma at about 8 km below Campi Flegrei, we suggest that the most-intense episodes of inflation occur when the gas supply to the sill-like reservoir comes from the 8 km-deep magma, although fluids exsolved by magma bodies at shallower depths also contribute to the gas budget. Our work highlights that, in caldera systems where the presence of hydrothermal aquifers commonly masks the magmatic signature

  7. A stream sediment geochemical survey of the Ganga River headwaters in the Garhwal Himalaya

    Science.gov (United States)

    Mukherjee, P.K.; Purohit, K.K.; Saini, N.K.; Khanna, P.P.; Rathi, M.S.; Grosz, A.E.

    2007-01-01

    This study models geochemical and adjunct geologic data to define provinces that are favorable for radioactive-mineral exploration. A multi-element bed-sediment geochemical survey of streams was carried out in the headwaters region of the Ganga River in northern India. Overall median values for uranium and thorium (3.6 and 13.8 ppm; maxima of 4.8 and 19.0 ppm and minima of 3.1 and 12.3 ppm respectively) exceed average upper crustal abundances (2.8 and 10.7 ppm) for these radioactive elements. Anomalously high values reach up to 8.3 and 30.1 ppm in thrust zone rocks, and 11.4 and 22.5 ppm in porphyroids. At their maxima, these abundances are nearly four- and three-fold (respectively) enriched in comparison to average crustal abundances for these rock types. Deformed, metamorphosed and sheared rocks are characteristic of the main central thrust zone (MCTZ). These intensively mylonitized rocks override and juxtapose porphyritic (PH) and proterozoic metasedimentary rock sequences (PMS) to the south. Granitoid rocks, the major protoliths for mylonites, as well as metamorphosed rocks in the MCT zone are naturally enriched in radioelements; high values associated with sheared and mylonitized zones are coincident with reports of radioelement mineralization and with anomalous radon concentrations in soils. The radioelement abundance as well as REE abundance shows a northward enrichment trend consistent with increasing grade of metamorphism indicating deformation-induced remobilization of these elements. U and Th illustrate good correlation with REEs but not with Zr. This implies that zircon is not a principal carrier of U and Th within the granitoid-dominant thrust zone and that other radioelement-rich secondary minerals are present in considerable amounts. Thus, the relatively flat, less fractionated, HREE trend is also not entirely controlled by zircon. The spatial correlation of geologic boundary zones (faults, sheared zones) with geochemical and with geophysical (Rn

  8. Alligator Rivers Analogue project. Geophysics, petrophysics and structure

    International Nuclear Information System (INIS)

    Emerson, D.W.; Mills, K.J.; Hallett, M.S.; Cao, L.Q.; Miyakawa, K.

    1992-01-01

    The geophysical and geological field work at Koongarra (including borehole core logging) showed that the site itself is a folded, faulted, variably fractured Precambrian psammitic and pelitic schist sequence with a quasi-horizontal weathered zone superimposed on the steeply dipping rock fabric. The site is flanked by a high resistivity younger sandstone unit to the northwest and by a magnetic amphibolite/ferricrete sequence to the far southeast. The data interpretations elicited the essential structural and broad lithological elements. Gravity, magnetic and electrical laboratory and field studies confirmed a broad folded fractured sequence of dipping layered host rocks weathered in their upper parts and trending in a southwest-northeast direction. Qualitatively interpreted anomalies indicated the trend of the main groundwater movement to the south where dolomites are thought to act as a sink. These drainage features have SP, resistivity and radiometric expression. The roles of the Kombolgie Sandstone as a source of water and the Koongarra Fault as a barrier or otherwise were not established owing to the lack of sufficient samples for testing and also on account of the difficulty of geophysical access over the site's rugged escarpment. 40 refs., 13 tabs., 69 figs

  9. Geophysics: Building E5481 decommissioning, Aberdeen Proving Ground

    International Nuclear Information System (INIS)

    Thompson, M.D.; McGinnis, M.G.; McGinnis, L.D.; Miller, S.F.

    1992-11-01

    Building E5481 is one of ten potentially contaminated sites in the Canal Creek and Westwood areas of the Edgewood section of Aberdeen Proving Ground examined by a geophysical team from Argonne National Laboratory in April and May of 1992. Noninvasive geophysical surveys, including magnetics, electrical resistivity, and ground-penetrating radar, were conducted around the perimeter of the building to guide a sampling program prior to decommissioning and dismantling. The building is located on the northern margin of a landfill that was sited in a wetland. The large number of magnetic sources surrounding the building are believed to be contained in construction fill that had been used to raise the grade. The smaller anomalies, for the most part, are not imaged with ground radar or by electrical profiling. A conductive zone trending northwest to southeast across the site is spatially related to an old roadbed. Higher resistivity areas in the northeast and east are probably representive of background values. Three high-amplitude, positive, rectangular magnetic anomalies have unknown sources. The features do not have equivalent electrical signatures, nor are they seen with radar imaging

  10. Geophysics: Building E5476 decommissiong, Aberdeen Proving Ground

    International Nuclear Information System (INIS)

    Miller, S.F.; Thompson, M.D.; McGinnis, M.G.; McGinnis, L.D.

    1992-11-01

    Building E5476 was one of ten potentially contaminated sites in the Canal Creek and Westwood areas of the Edgewood section of Aberdeen Proving Ground examined by a geophysical team from Argonne National Laboratory in April and May of 1992. Noninvasive geophysical surveys, including magnetics, electrical resistivity, and ground-penetrating radar, were conducted around the perimeter of the building to guide a sampling program prior to decommissioning and dismantling. The large number of magnetic sources surrounding the building are believed to be contained in construction fill. The smaller anomalies, for the most part, were not imaged with ground radar or by electrical profiling. Large magnetic anomalies near the southwest comer of the building are due to aboveground standpipes and steel-reinforced concrete. Two high-resistivity areas, one projecting northeast from the building and another south of the original structure, may indicate the presence of organic pore fluids in the subsurface. A conductive lineament protruding from the south wall that is enclosed by the southem, high-resistivity feature is not associated with an equivalent magnetic anomaly. Magnetic and electrical anomalies south of the old landfill boundary are probably not associated with the building. The boundary is marked by a band of magnetic anomalies and a conductive zone trending northwest to southeast. The cause of high resistivities in a semicircular area in the southwest comer, within the landfill area, is unexplained

  11. Geophysics: Building E5375 decommissioning, Aberdeen Proving Ground

    International Nuclear Information System (INIS)

    McGinnis, M.G.; McGinnis, L.D.; Miller, S.F.; Thompson, M.D.

    1992-08-01

    Building E5375 was one of ten potentially contaminated sites in the Canal Creek area of the Edgewood section of Aberdeen Proving Ground examined by a geophysical team from Argonne National Laboratory in April and May 1992. Noninvasive geophysical surveys, including magnetics, electrical resistivity, and ground-penetrating radar (GPR), were conducted around the perimeter of the building to guide a sampling program prior to decommissioning and dismantling. Several anomalies wear, noted: (1) An underground storage tank located 25 ft east of Building E5375 was identified with magnetic, resistivity, and GPR profiling. (2) A three-point resistivity anomaly, 12 ft east of the northeast comer of Building E5374 (which borders Building E5375) and 5 ft south of the area surveyed with the magnetometer, may be caused by another underground storage tank. (3) A 2,500-gamma magnetic anomaly near the northeast corner of the site has no equivalent resistivity anomaly, although disruption in GPR reflectors was observed. (4) A one-point magnetic anomaly was located at the northeast comer, but its source cannot be resolved. A chaotic reflective zone to the east represents the radar signature of Building E5375 construction fill

  12. Definition of a critical confining zone using surface geophysical methods

    International Nuclear Information System (INIS)

    Eddy-Dilek, C.A.; Hoekstra, P.; Harthill, N.; Blohm, M.; Phillips, D.R.

    1996-01-01

    Definition of the hydrogeologic framework in layered sediments of fluvial and deltaic origin is a difficult challenge for environmental characterization and remediation programs due to the lithologic and stratigraphic heterogeneities inherent in these settings. These heterogeneties often control contaminant transport and the effectiveness of remediation alternatives, Surface geophysical surveys can be cost-effective methods for characterization, but individual methods have inherent limitations in resolution and sensitivity. A synergistic approach, utilizing two geophysical survey methods was applied, to define and examine the nature and extent of a deep confining zone of regulatory importance, the Crouch Branch Confining Unit, in Coastal Plain sediments at the Savannah River Site. TDEM accurately maps the overall conductance (product of thickness and electrical conductivity) of a confining zone clay facies; from variation in conductance, changes in lithology of the conforming zone can be inferred. Shear wave seismic reflection surveys map the depth to the clay layers, and the clay layer thickness, but provides little information on the lithologic nature of the confining zone. Integrated interpretation of the combined data set (including all available borehole logs) allows for delineation of the lateral and vertical extent of clay-dominated zones, sand-dominated zones, key stratigraphic horizons, and erosional features associated with unconformities. This approach has resulted in the collection of critical information that will be used to optimize remedial system design, representing a significant cost savings to environmental restoration programs at the Savannah River Site

  13. How Collecting and Freely Sharing Geophysical Data Broadly Benefits Society

    Science.gov (United States)

    Frassetto, A.; Woodward, R.; Detrick, R. S.

    2017-12-01

    Valuable but often unintended observations of environmental and human-related processes have resulted from open sharing of multidisciplinary geophysical observations collected over the past 33 years. These data, intended to fuel fundamental academic research, are part of the Incorporated Research Institutions for Seismology (IRIS), which is sponsored by the National Science Foundation and has provided a community science facility supporting earthquake science and related disciplines since 1984. These community facilities have included arrays of geophysical instruments operated for EarthScope, an NSF-sponsored science initiative designed to understand the architecture and evolution of the North American continent, as well as the Global Seismographic Network, Greenland Ice Sheet Monitoring Network, a repository of data collected around the world, and other community assets. All data resulting from this facility have been made openly available to support researchers across any field of study and this has expanded the impact of these data beyond disciplinary boundaries. This presentation highlights vivid examples of how basic research activities using open data, collected as part of a community facility, can inform our understanding of manmade earthquakes, geomagnetic hazards, climate change, and illicit testing of nuclear weapons.

  14. New determination of period and quality factor of Chandler wobble, considering geophysical excitations

    Czech Academy of Sciences Publication Activity Database

    Vondrák, Jan; Ron, Cyril; Chapanov, Y.

    2017-01-01

    Roč. 59, č. 5 (2017), s. 1395-1407 ISSN 0273-1177 R&D Projects: GA ČR GA13-15943S Institutional support: RVO:67985815 Keywords : polar motion * chandler wobble * geophysical excitations Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics OBOR OECD: Astronomy (including astrophysics,space science) Impact factor: 1.401, year: 2016

  15. Solar-Geophysical Data Number 514, June 1987. Part 2 (comprehensive reports). Data for December 1986

    International Nuclear Information System (INIS)

    Coffey, H.E.; McKinnon, J.A.

    1987-06-01

    Contents include: Detailed index for 1986-1987; Data for December 1986--Meudon carte synoptique; Solar flares, Solar radio bursts at fixed frequencies, Solar x-ray radiation from GOES satellite graphs, Mass ejections from the sun, Active prominences and filaments, Miscellaneous data--Chinese solar-geophysical data (CSGD) (Explanation of Data Reports)

  16. WATEQ3 geochemical model: thermodynamic data for several additional solids

    International Nuclear Information System (INIS)

    Krupka, K.M.; Jenne, E.A.

    1982-09-01

    Geochemical models such as WATEQ3 can be used to model the concentrations of water-soluble pollutants that may result from the disposal of nuclear waste and retorted oil shale. However, for a model to competently deal with these water-soluble pollutants, an adequate thermodynamic data base must be provided that includes elements identified as important in modeling these pollutants. To this end, several minerals and related solid phases were identified that were absent from the thermodynamic data base of WATEQ3. In this study, the thermodynamic data for the identified solids were compiled and selected from several published tabulations of thermodynamic data. For these solids, an accepted Gibbs free energy of formation, ΔG 0 /sub f,298/, was selected for each solid phase based on the recentness of the tabulated data and on considerations of internal consistency with respect to both the published tabulations and the existing data in WATEQ3. For those solids not included in these published tabulations, Gibbs free energies of formation were calculated from published solubility data (e.g., lepidocrocite), or were estimated (e.g., nontronite) using a free-energy summation method described by Mattigod and Sposito (1978). The accepted or estimated free energies were then combined with internally consistent, ancillary thermodynamic data to calculate equilibrium constants for the hydrolysis reactions of these minerals and related solid phases. Including these values in the WATEQ3 data base increased the competency of this geochemical model in applications associated with the disposal of nuclear waste and retorted oil shale. Additional minerals and related solid phases that need to be added to the solubility submodel will be identified as modeling applications continue in these two programs

  17. Research on geochemical exploration in geotherm development

    International Nuclear Information System (INIS)

    Hirowatari, Kazuo; Imaizumi, Yukio; Koga, Akito; Iwanaga, Tatsuto.

    1987-01-01

    The decisive factor of geotherm development is to improve the exploration techniques. By effectively carrying out the selection of promising development spots and the decision of well drilling positions, the geotherm development exceeding existing energy sources becomes feasible. There have been many problems in conventional geotherm exploration such as the high cost and long work period, therefore, it was decided to advance the research on geochemical exploration techniques which are relatively simple and can be carried out with low cost. When the techniques of geochemistry are used, for example, in the case that there are hot springs or fumaroles, the temperature, origin, properties and so on of underground hot water reservoirs can be estimated from their chemical composition. The method of examining the mercury concentration in soil and soil air has been in practical use in the geothermal districts where the ground surface symptom lacks. This time, the method of investigation using radon, thoron and gamma ray as the exploration indices was newly studied. The index compositions for geochemical exploration, new exploration index compositions, the method of measurement, the basic investigation and on-the-spot investigation are reported. (Kako, I.)

  18. Geochemical signature of radioactive waste: oil NORM

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Gilberto T. de Paula; Costa-de-Moura, Jorge; Gomes, Carlos de Almeida; Sampaio, Emidio A. Lopes, E-mail: gilberto.costa@cnen.gov.br, E-mail: jcmoura@cnen.gov.br, E-mail: cgomes@cnen.gov.br [Comissao Nacional de Energia Nuclear (CNEN), Rio de Janeiro, RJ (Brazil). Div. de Controle de Rejeitos e Transporte de Materiais Radioativos

    2017-07-01

    The Brazilian Nuclear Agency (CNEN) rules all nuclear activity in Brazil as demanded by the Federal Constitution, articles 21, XXIII, and 177, V, and by the Federal Acts 4.118/62 and 10.308/2001. Therefore, the CNEN is responsible for any radioactive waste disposal in the country. Oil Naturally Occurring Radioactive Materials (Oil NORM) in this paper refers to waste coming from oil exploration. Oil NORM has called much attention during the last decades, mostly because it is not possible to determine its primary source due to the actual absence of regulatory control mechanism. There is no efficient regulatory tool which allows determining the origin of such NORM wastes even among those facilities under regulatory control. This fact may encourage non-authorized radioactive material transportation, smuggling and terrorism. The aim of this project is to provide a geochemical signature for each oil NORM waste using its naturally occurring isotopic composition to identify its origin. The here proposed method is a specific geochemical modeling of oil sludge NORM samples which are analyzed for radioisotopes normally present in oil pipes, such as {sup 228}Ac, {sup 214}Bi and {sup 214}Pb. The activity ratios are plotted in scatter diagrams. This method was successfully tested with data of different sources obtained from analysis reports from the Campos Basin/Brazil and from literature. (author)

  19. Neutron activation analysis of geochemical samples

    International Nuclear Information System (INIS)

    Rosenberg, R.; Zilliacus, R.; Kaistila, M.

    1983-06-01

    The present paper will describe the work done at the Technical Research Centre of Finland in developing methods for the large-scale activation analysis of samples for the geochemical prospecting of metals. The geochemical prospecting for uranium started in Finland in 1974 and consequently a manually operated device for the delayed neutron activation analysis of uranium was taken into use. During 1974 9000 samples were analyzed. The small capacity of the analyzer made it necessary to develop a completely automated analyzer which was taken into use in August 1975. Since then 20000-30000 samples have been analyzed annually the annual capacity being about 60000 samples when running seven hours per day. Multielemental instrumental neutron activation analysis is used for the analysis of more than 40 elements. Using instrumental epithermal neutron activation analysis 25-27 elements can be analyzed using one irradiation and 20 min measurement. During 1982 12000 samples were analyzed for mining companies and Geological Survey of Finland. The capacity is 600 samples per week. Besides these two analytical methods the analysis of lanthanoids is an important part of the work. 11 lanthanoids have been analyzed using instrumental neutron activation analysis. Radiochemical separation methods have been developed for several elements to improve the sensitivity of the analysis

  20. Geochemical signature of radioactive waste: oil NORM

    International Nuclear Information System (INIS)

    Costa, Gilberto T. de Paula; Costa-de-Moura, Jorge; Gomes, Carlos de Almeida; Sampaio, Emidio A. Lopes

    2017-01-01

    The Brazilian Nuclear Agency (CNEN) rules all nuclear activity in Brazil as demanded by the Federal Constitution, articles 21, XXIII, and 177, V, and by the Federal Acts 4.118/62 and 10.308/2001. Therefore, the CNEN is responsible for any radioactive waste disposal in the country. Oil Naturally Occurring Radioactive Materials (Oil NORM) in this paper refers to waste coming from oil exploration. Oil NORM has called much attention during the last decades, mostly because it is not possible to determine its primary source due to the actual absence of regulatory control mechanism. There is no efficient regulatory tool which allows determining the origin of such NORM wastes even among those facilities under regulatory control. This fact may encourage non-authorized radioactive material transportation, smuggling and terrorism. The aim of this project is to provide a geochemical signature for each oil NORM waste using its naturally occurring isotopic composition to identify its origin. The here proposed method is a specific geochemical modeling of oil sludge NORM samples which are analyzed for radioisotopes normally present in oil pipes, such as 228 Ac, 214 Bi and 214 Pb. The activity ratios are plotted in scatter diagrams. This method was successfully tested with data of different sources obtained from analysis reports from the Campos Basin/Brazil and from literature. (author)

  1. Investigation of a natural geochemical barrier

    International Nuclear Information System (INIS)

    1991-02-01

    Groundwater data from lysimeters and monitor wells in the vicinity of the Bowman, North Dakota, Uranium Mill Tailings Remedial Action (UMTRA) Project site indicated that there is a mechanism in the subsurface which cleans up downward-percolating fluids. It was hypothesized that clays and organic materials in the sediments sequestered hazardous constituents from infiltrating fluids. A program was designed to collect sediment cores from various locations on and around the site and to analyze the sediments to determine whether there has been a build up of hazardous constituents in any specific type of sedimentary material. Materials that concentrate the hazardous constituents would be potential candidates to be used in constructed geochemical barriers. The water quality of the groundwater contained within the sedimentary section indicates that there is a transport of contaminants down through the sediments and that these contaminants are removed from solution by the iron-bearing minerals in the organic-rich lignite beds. The data gathered during the course of this investigation indicate that the lignite ashing operations have added very little of the hazardous constituents of concern--arsenic, chromium, molybdenum, selenium, or uranium--to the sediments beneath the UMTRA Project site. At both locations, the hazardous constituents are concentrated in the upper most lignite bed. These data offer a natural analog for laboratory tests in which sphagnum peat was used to sequester hazardous constituents. Constructed geochemical barriers are a viable mechanism for the clean-up of the majority of hazardous constituents from uranium mill tailings in groundwater

  2. Geochemical controls on groundwater chemistry in shales

    International Nuclear Information System (INIS)

    Von Damm, K.L.

    1989-01-01

    The chemistry of groundwaters is one of the most important parameters in determining the mobility of species within a rock formation. A three pronged approach was used to determine the composition of, and geochemical controls, on groundwaters specifically within shale formations: (1) available data were collected from the literature, the US Geological Survey WATSTORE data base, and field sampling, (2) the geochemical modeling code EQ3/6 was used to simulate interaction of various shales and groundwaters, and (3) several types of shale were reacted with synthetic groundwaters in the laboratory. The comparison of model results to field and laboratory data provide a means of validating the models, as well as a means of deconvoluting complex field interactions. Results suggest that groundwaters in shales have a wide range in composition and are primarily of the Na-Cl-HCO 3 - type. The constancy of the Na:Cl (molar) ratio at 1:1 and the Ca:Mg ratio from 3:1 to 1:1 suggests the importance of halite and carbonates in controlling groundwater compositions. In agreement with the reaction path modeling, most of the groundwaters are neutral to slightly alkaline at low temperatures. Model and experimental results suggest that reaction (1) at elevated temperatures, or (2) in the presence of oxygen will lead to more acidic conditions. Some acetate was found to be produced in the experiments; depending on the constraints applied, large amounts of acetate were produced in the model results. 13 refs., 1 tab

  3. Garnet Signatures in Geophysical and Geochemical Observations: Insights into the Thermo-Petrological Structure of Oceanic Upper Mantle

    Science.gov (United States)

    Grose, C. J.; Afonso, J. C.

    2013-12-01

    We have developed new physically comprehensive thermal plate models of the oceanic lithosphere which incorporate temperature- and pressure-dependent heat transport properties and thermal expansivity, melting beneath ridges, hydrothermal circulation near ridge axes, and insulating oceanic crust. These models provide good fits to global databases of seafloor topography and heat flow, and seismic evidence of thermal structure near ridge axes. We couple these thermal plate models with thermodynamic models to predict the petrology of oceanic lithosphere. Geoid height predictions from our models suggest that there is a strong anomaly in geoid slope (over age) above ~25 Ma lithosphere due to the topography of garnet-field mantle. A similar anomaly is also present in geoid data over fracture zones. In addition, we show that a new assessment of a large database of ocean island basalt Sm/Yb systematics indicates that there is an unmistakable step-like increase in Sm/Yb values around 15-20 Ma, indicating the presence of garnet. To explain this feature, we have attempted to couple our thermo-petrological models of oceanic upper mantle with an open system, non-modal, dynamic melting model with diffusion kinetics to investigate trace element partitioning in an ascending mantle column.

  4. Advances in Airborne and Ground Geophysical Methods for Uranium Exploration

    International Nuclear Information System (INIS)

    2013-01-01

    One of the IAEA's statutory objectives is to 'seek to accelerate and enlarge the contribution of atomic energy to peace, health and prosperity throughout the world'. One way this objective is achieved is through the publication of a range of technical series. Two of these are the IAEA Nuclear Energy Series and the IAEA Safety Standards Series. According to Article III.A.6 of the IAEA Statute, the safety standards establish 'standards of safety for protection of health and minimization of danger to life and property.' The safety standards include the Safety Fundamentals, Safety Requirements and Safety Guides. These standards are written primarily in a regulatory style, and are binding on the IAEA for its own programmes. The principal users are the regulatory bodies in Member States and other national authorities. The IAEA Nuclear Energy Series comprises reports designed to encourage and assist R and D on, and application of, nuclear energy for peaceful uses. This includes practical examples to be used by owners and operators of utilities in Member States, implementing organizations, academia, and government officials, among others. This information is presented in guides, reports on technology status and advances, and best practices for peaceful uses of nuclear energy based on inputs from international experts. The IAEA Nuclear Energy Series complements the IAEA Safety Standards Series. According to current estimates, after 2050 available resources and cumulative uranium demand are expected to be balanced. Recent annual uranium production constitutes 65-75% of annual nuclear energy uranium requirements worldwide. With typical timeframes of between 15 and 40 years from the commencement of uranium exploration activities until uranium production, together with increasingly favourable uranium prices, many countries have seen a rise in uranium exploration activities since 2005. This experience and assessment of global energy needs support continued uranium exploration

  5. Hydrogeological and geochemical studies in the Perch Lake basin

    International Nuclear Information System (INIS)

    Barry, P.J.

    1979-08-01

    The Perch Lake basin is a small drainage system along the Ottawa River about 200 km west of Ottawa on the Canadian Shield. Since 1975, groups of scientists from several Canadian universities and government departments have been studying the hydrological, geological and geochemical properties of the basin. The object of these studies is to develop and test simulation models used to describe the time-dependent mass flow rates of water and dissolved and suspended substances through the basin. To review progress, a symposium/workshop was held at Chalk Rier in 1978 April. This report contains 24 extended summaries of the material presented verbally at the workshop. Subject matters include atmospheric sources and sinks, mass flows through the surface and subsurface regimes in the drainage basins and interactions occurring in the lake. (author)

  6. Geochemical exploration for phosphate in the State of Acre

    International Nuclear Information System (INIS)

    Costa, M.L. da; Melo Costa, W.A. de; Santos, A.J.M. dos

    1989-01-01

    The geochemical prospecting conducted for phosphates in Acre which could explain the good fertility of the region was charged to discover this material. The phosphates are strictly built of all the bone structures and coprolites of the several fragments of vertebrate fossils, which are widespread in the region. The phosphatic fossils are bedded in the Solimoes Formation, especially its basal to intermediary conglomeratic bed. The fossils are constituted of low crystallinity apatite, and their matrix sediments include quartz, feldspars, smectite, halloysite and calcite. The P 2 O 5 content reaches up to 5% in the sediments and up to 32% in the fragments. The fossils are enriched in U 3 O 8 and rare earth elements. There is no perspect of classic or mineral deposits but the geological knowlwdge will permit the improvement of the use of the soils in Acre. (author) [pt

  7. From Mathematical Monsters to Generalized Scale Invariance in Geophysics: Highlights of the Multifractal Saga

    Science.gov (United States)

    Schertzer, D. J.; Tchiguirinskaia, I.; Lovejoy, S.

    2013-12-01

    Fractals and multifractals are very illustrative of the profound synergies between mathematics and geophysics. The book ';Fractal Geometry of Nature' (Mandelbrot, 1982) brilliantly demonstrated the genericity in geophysics of geometric forms like Cantor set, Peano curve and Koch snowflake, which were once considered as mathematical monsters. However, to tame the geophysical monsters (e.g. extreme weather, floods, earthquakes), it was required to go beyond geometry and a unique fractal dimension. The concept of multifractal was coined in the course of rather theoretical debates on intermittency in hydrodynamic turbulence, sometimes with direct links to atmospheric dynamics. The latter required a generalized notion of scale in order to deal both with scale symmetries and strong anisotropies (e.g. time vs. space, vertical vs. horizontal). It was thus possible to show that the consequences of intermittency are of first order, not just 'corrections' with respect to the classical non-intermittent modeling. This was in fact a radical paradigm shift for geophysics: the extreme variability of geophysical fields over wide ranges of scale, which had long been so often acknowledged and deplored, suddenly became handy. Recent illustrations are the possibility to track down in large date sets the Higgs boson of intermittence, i.e. a first order multifractal phase transition leading to self-organized criticality, and to simulate intermittent vector fields with the help of Lie cascades, based for instance on random Clifford algebra. It is rather significant that this revolution is no longer limited to fundamental and theoretical problems of geophysics, but now touches many applications including environmental management, in particular for urban management and resilience. These applications are particularly stimulating when taken in their full complexity.

  8. pyGIMLi: An open-source library for modelling and inversion in geophysics

    Science.gov (United States)

    Rücker, Carsten; Günther, Thomas; Wagner, Florian M.

    2017-12-01

    Many tasks in applied geosciences cannot be solved by single measurements, but require the integration of geophysical, geotechnical and hydrological methods. Numerical simulation techniques are essential both for planning and interpretation, as well as for the process understanding of modern geophysical methods. These trends encourage open, simple, and modern software architectures aiming at a uniform interface for interdisciplinary and flexible modelling and inversion approaches. We present pyGIMLi (Python Library for Inversion and Modelling in Geophysics), an open-source framework that provides tools for modelling and inversion of various geophysical but also hydrological methods. The modelling component supplies discretization management and the numerical basis for finite-element and finite-volume solvers in 1D, 2D and 3D on arbitrarily structured meshes. The generalized inversion framework solves the minimization problem with a Gauss-Newton algorithm for any physical forward operator and provides opportunities for uncertainty and resolution analyses. More general requirements, such as flexible regularization strategies, time-lapse processing and different sorts of coupling individual methods are provided independently of the actual methods used. The usage of pyGIMLi is first demonstrated by solving the steady-state heat equation, followed by a demonstration of more complex capabilities for the combination of different geophysical data sets. A fully coupled hydrogeophysical inversion of electrical resistivity tomography (ERT) data of a simulated tracer experiment is presented that allows to directly reconstruct the underlying hydraulic conductivity distribution of the aquifer. Another example demonstrates the improvement of jointly inverting ERT and ultrasonic data with respect to saturation by a new approach that incorporates petrophysical relations in the inversion. Potential applications of the presented framework are manifold and include time

  9. Increasing diversity in the geosciences through the AfricaArray geophysics field course

    Science.gov (United States)

    Vallejo, G.; Emry, E.; Galindo, B. L.; Carranza, V.; Gomez, C. D.; Ortiz, K.; Castro, J. G.; Guandique, J.; Falzone, C.; Webb, S. J.; Manzi, M.; Mngadi, S. B.; Stephens, K.; Chinamora, B.; Whitehead, R.; de Villiers, D. P.; Tshitlho, K.; Delhaye, R. P.; Smith, J. A.; Nyblade, A.

    2014-12-01

    For the past nine years, the AfricaArray diversity program, sponsored by industry, the National Science Foundation, and several partnering universities have supported outstanding U.S. STEM underrepresented minority undergraduates to gain field experience in near-surface geophysical techniques during an 8-week summer program at Penn State University and the University of Witwatersrand (Wits). The AfricaArray geophysics field school, which is run by Wits, has been teaching field-based geophysics to African students for over a decade. In the first 2-3 weeks of the program, the U.S. students are given basic instruction in near-surface geophysics, South African geology, and South African history and culture. The students then join the Wits AfricaArray geophysics field school - working alongside Wits students and students from several other African universities to map the shallow subsurface in prospective areas of South Africa for platinum mining. In addition to the primary goals of collecting and interpreting gravity, magnetic, resistivity, seismic refraction, seismic reflection, and EM data, students spend time mapping geologic units and gathering information on the physical properties of the rocks in the region (i.e. seismic velocity, density, and magnetic susceptibility). Subsurface targets include mafic dikes, faults, the water table, and overburden thickness. Upon returning to the U.S., students spend 2-3 weeks finalizing their project reports and presentations. The program has been effective at not only providing students with fundamental skills in applied geophysics, but also in fostering multicultural relationships, preparing students for graduate work in the geosciences, and attracting STEM students into the geosciences. Student presenters will discuss their experiences gained through the field school and give their impressions about how the program works towards the goal of increasing diversity in the geosciences in the U.S.

  10. Description of geophysical data in the SKB database GEOTAB

    International Nuclear Information System (INIS)

    Sehlstedt, S.

    1988-02-01

    For the storage of different types of data collected by SKB a database called Geotab has been created. The following data are stored in the database: Background data, geological data, geophysical data, hydrogeological data, hydrochemical data. This report describes the data flow for different types of geophysical measurements. The descriptions start with measurements and end with the storage of data in Geotab. Each process and the resulting data volume is presented separately. The geophysical measurements have been divided into the following subjects: Geophysical ground surface measurements, profile measurements; geophysical ground surface measurements, grid net measurements; geophysical borehole logging; petrophysical measurements. Each group of measurements is described in an individual chapter. In each chapter several measuring techniques are described and each method has a data table and a flyleaf table in Geotab. (orig.)

  11. Informing groundwater models with near-surface geophysical data

    DEFF Research Database (Denmark)

    Herckenrath, Daan

    Over the past decade geophysical methods have gained an increased popularity due to their ability to map hydrologic properties. Such data sets can provide valuable information to improve hydrologic models. Instead of using the measured geophysical and hydrologic data simultaneously in one inversion...... approach, many of the previous studies apply a Sequential Hydrogeophysical Inversion (SHI) in which inverted geophysical models provide information for hydrologic models. In order to fully exploit the information contained in geophysical datasets for hydrological purposes, a coupled hydrogeophysical...... inversion was introduced (CHI), in which a hydrologic model is part of the geophysical inversion. Current CHI-research has been focussing on the translation of simulated state variables of hydrologic models to geophysical model parameters. We refer to this methodology as CHI-S (State). In this thesis a new...

  12. A fractured rock geophysical toolbox method selection tool

    Science.gov (United States)

    Day-Lewis, F. D.; Johnson, C.D.; Slater, L.D.; Robinson, J.L.; Williams, J.H.; Boyden, C.L.; Werkema, D.D.; Lane, J.W.

    2016-01-01

    Geophysical technologies have the potential to improve site characterization and monitoring in fractured rock, but the appropriate and effective application of geophysics at a particular site strongly depends on project goals (e.g., identifying discrete fractures) and site characteristics (e.g., lithology). No method works at every site or for every goal. New approaches are needed to identify a set of geophysical methods appropriate to specific project goals and site conditions while considering budget constraints. To this end, we present the Excel-based Fractured-Rock Geophysical Toolbox Method Selection Tool (FRGT-MST). We envision the FRGT-MST (1) equipping remediation professionals with a tool to understand what is likely to be realistic and cost-effective when contracting geophysical services, and (2) reducing applications of geophysics with unrealistic objectives or where methods are likely to fail.

  13. Atmospheric and Geophysical Sciences Division: Program report, FY 1987

    International Nuclear Information System (INIS)

    1988-05-01

    In 1988 the Atmospheric and Geophysical Sciences Division began its 15th year as a division. As the Division has grown over the years, its modeling capabilities have expanded to include a broad range of time and space scales ranging from hours to years, and from kilometers to global, respectively. For this report, we have chosen to show a subset of results from several projects to illustrate the breadth, depth, and diversity of the modeling activities that are a major part of the Division's research, development, and application efforts. In addition, the recent reorganization of the Division, including the merger of another group with the Division, is described, and the budget, personnel, models, and publications are reviewed. 95 refs., 26 figs., 2 tabs

  14. Geochemical Constraints on Archaeal Diversity in the Vulcano Hydrothermal System

    Science.gov (United States)

    Rogers, K. L.; Amend, J. P.

    2006-12-01

    The shallow marine hydrothermal system of Vulcano, Italy hosts a wide diversity of cultured thermophilic Archaea, including Palaeococcus helgesonii, Archaeoglobus fulgidus, and Pyrococcus furiosus, to name a few. However, recent studies have revealed a plethora of uncultured archaeal lineages in the Vulcano system. For example, a 16S rRNA gene survey of an onshore geothermal well identified a diverse archaeal community including deeply-branching uncultured Crenarchaeota, Korarchaeota, and Euryarchaeota. Additionally, culture-independent hybridization techniques suggested that Archaea account for nearly half of the microbial community in the Vulcano system. Furthermore, geochemical characterization of fluids revealed numerous lithotrophic and heterotrophic exergonic reactions that could support as yet uncultured organisms. Archaeal diversity throughout the Vulcano hydrothermal system was investigated using 16S rRNA gene surveys at five submarine vents and an onshore sediment seep. Overall, archaeal diversity was higher (10 groups) at submarine vents with moderate temperatures (59°C) compared with higher temperature (94°C) vents (4 groups). Archaeal communities at the moderately thermal vents were dominated by Thermococcales and also contained Archaeoglobales, Thermoproteales, and uncultured archaea among the Korarchaeota, Marine Group I, and the Deep-sea Hydrothermal Vent Euryarchaeota (DHVE). Fluid composition also affects the microbial community structure. At two high-temperature sites variations in archaeal diversity can be attributed to differences in iron and hydrogen concentrations, and pH. Comparing sites with similar temperature and pH conditions suggests that the presence of Desulfurococcales is limited to sites at which metabolic energy yields exceed 10 kJ per mole of electrons transferred. The Vulcano hydrothermal system hosts diverse archaeal communities, containing both cultured and uncultured species, whose distribution appears to be constrained by

  15. Geochemical analysis of core from a geothermal anomaly

    International Nuclear Information System (INIS)

    Haverslew, B.; Tammemagi, H.Y.

    1985-04-01

    A mild geothermal area in western Montana, USA, has been studied, as a natural analog, to learn about the effects that long-term heat generated by a repository containing spent nuclear fuel might have on the surrounding rock mass. The results of previous geological, geophysical and hydrogeological studies are briefly summarized. Extensive petrological studies have been undertaken on core samples obtained from a 2 km deep borehole drilled into the Empire Creek Stock. These include a detailed petrographic study, x-ray diffraction analyses, scanning electron microscope and electron microprobe analyses, porosity and permeability measurements, oxygen isotope analyses, uranium disequilibrium analyses and K-Ar age determinations. The implications to deep burial of nuclear wastes are discussed. 40 refs

  16. Application of nuclear-geophysical methods to reserves estimation

    International Nuclear Information System (INIS)

    Bessonova, T.B.; Karpenko, I.A.

    1980-01-01

    On the basis of the analysis of reports dealing with calculations of mineral reserves considered are shortcomings in using nuclear-geophysical methods and in assessment of the reliability of geophysical sampling. For increasing efficiency of nuclear-geophysical investigations while prospecting ore deposits, it is advisable to introduce them widely instead of traditional geological sampling methods. For this purpose it is necessary to increase sensitivity and accuracy of radioactivity logging methods, to provide determination of certain elements in ores by these methods

  17. Artificial intelligence and dynamic systems for geophysical applications

    CERN Document Server

    Gvishiani, Alexei

    2002-01-01

    The book presents new clustering schemes, dynamical systems and pattern recognition algorithms in geophysical, geodynamical and natural hazard applications. The original mathematical technique is based on both classical and fuzzy sets models. Geophysical and natural hazard applications are mostly original. However, the artificial intelligence technique described in the book can be applied far beyond the limits of Earth science applications. The book is intended for research scientists, tutors, graduate students, scientists in geophysics and engineers

  18. Radioactive waste isolation in salt: peer review of the Office of Nuclear Waste Isolation's Geochemical Program Plan

    International Nuclear Information System (INIS)

    Harrison, W.; Seitz, M.; Fenster, D.; Lerman, A.; Brookins, D.; Tisue, M.

    1984-02-01

    Describe the management program for coordinating subcontractors and their work, and integrating research results. Appropriate flowcharts should be included. Provide more information on the overall scope of the program. For each subcontractor, provide specific workscopes that indicate whether analytical activities are developmental or routine, approximate number of analyses to be made, and something of the adequacy of the analyses to meet program goals. Indicate interfaces with other earth-science disciplines like hydrology and with other groups doing relevant geochemical research and engineering design. Address the priorities for each activity or group of activities. High priority should be given to early development of a geochemical statement of what constitutes suitable salt for a repository. Reference standard procedures for sampling, sample preservation, and sample analysis wherever appropriate or, if not appropriate, indicate that any deviations from standard procedures will be documented. Ensure that appropriate quality assurance procedures will be followed for the procedures listed above. Include specific procedures for the choice, verification, validation, and documentation of computer codes related to the geochemical aspects of repository performance assessment. Include activities addressing regional hydrochemistry and make clear that each principal hydrogeologic unit at each site will be studied geochemically. Indicate that proposed plans for obtaining hydrogeochemical data will be included in each site characterization plan. Describe how site geochemical stability will be handled, especially with respect to dissolution, postemplacement geochemistry, human influences, and climatic variations. Minor recommendations and suggested improvements in the text of the plan are given in Sec. 5

  19. Behaviour of nature and technogenic radioisotopes in buried geochemical barriers

    International Nuclear Information System (INIS)

    Kuznetsov, V.A.; Onoshko, M.P.; Generalova, V.A.

    1998-01-01

    Behaviour of potassium 40, radium 226, thorium 232, strontium 90 and cesium 137 on geochemical barriers connected with buried soils and cut-off meander sediments of the Holocene age of the Sozh river valley are examined. Some sides of the barrier geochemical structure caused by syngeneic and epigenetic processes have been taken into consideration

  20. ''Radon-emanometry'' applied to internal geophysics

    International Nuclear Information System (INIS)

    Seidel, J.L.

    1982-02-01

    An experimental set-up for in ground radon 222 measurements has been realised with solid state track detectors (cellulose nitrates CN85 and LR115). A preliminary study of radon activity variations has been conducted over various sites expecting using radon as one of forerunner geophysical parameters of volcanic eruptions and earthquakes predictions. The first data obtained in the field are presented: Etna (Sicily), Krafla (Iceland), Poas and Arenal (Costa Rica), Colima and Paricutin (Mexico) for active volcanoes, Ech Cheliff (Algeria) and Alsace (France) for sismotectonic areas [fr

  1. Surface exploration geophysics applied to the moon

    International Nuclear Information System (INIS)

    Ander, M.E.

    1984-01-01

    With the advent of a permanent lunar base, the desire to explore the lunar near-surface for both scientific and economic purposes will arise. Applications of exploration geophysical methods to the earth's subsurface are highly developed. This paper briefly addresses some aspects of applying this technology to near surface lunar exploration. It is noted that both the manner of application of some techniques, as well as their traditional hierarchy as assigned on earth, should be altered for lunar exploration. In particular, electromagnetic techniques may replace seismic techniques as the primary tool for evaluating near-surface structure

  2. Geophysical techniques used in uranium exploration

    International Nuclear Information System (INIS)

    Meyer, P.A.

    1977-01-01

    The impetus in uranium exploration has been generated by the increase in price to about $40.00 a pound or $2.50 an ounce, a price that approaches a precious metal. Not only has the search increased in the traditional sandstone areas, but also in the igneous and metamorphic environments. Because uranium is one of the elements along with thorium and potassium that radiate alpha, beta and gamma rays; direct methods have been developed and improved upon to measure this radiation while indirect traditional geophysical methods have been used to assist in locating associated favorable structural and ''stratigraphic'' zones

  3. Large natural geophysical events: planetary planning

    International Nuclear Information System (INIS)

    Knox, J.B.; Smith, J.V.

    1984-09-01

    Geological and geophysical data suggest that during the evolution of the earth and its species, that there have been many mass extinctions due to large impacts from comets and large asteroids, and major volcanic events. Today, technology has developed to the stage where we can begin to consider protective measures for the planet. Evidence of the ecological disruption and frequency of these major events is presented. Surveillance and warning systems are most critical to develop wherein sufficient lead times for warnings exist so that appropriate interventions could be designed. The long term research undergirding these warning systems, implementation, and proof testing is rich in opportunities for collaboration for peace

  4. Geophysical excitation of the chandler wobble revisited

    OpenAIRE

    A. Brzezinski; Henryk Dobslaw; Robert Dill; Maik Thomas

    2012-01-01

    The 14-month Chandler wobble is a free motion of the pole excited by geophysical processes. Several recent studies demonstrated that the combination of atmospheric and oceanic excitations contains enough power at the Chandler frequency and is significantly coherent with the observed free wobble. This paper is an extension of earlier studies by Brzeziński and Nastula (Adv Space Res 30:195–200, 2002), Brzeziński et al. (Oceanic excitation of the Chandler wobble using a 50-year time series of oc...

  5. EGS Richardson AGU Chapman NVAG3 Conference: Nonlinear Variability in Geophysics: scaling and multifractal processes

    Directory of Open Access Journals (Sweden)

    D. Schertzer

    1994-01-01

    Full Text Available 1. The conference The third conference on "Nonlinear VAriability in Geophysics: scaling and multifractal processes" (NVAG 3 was held in Cargese, Corsica, Sept. 10-17, 1993. NVAG3 was joint American Geophysical Union Chapman and European Geophysical Society Richardson Memorial conference, the first specialist conference jointly sponsored by the two organizations. It followed NVAG1 (Montreal, Aug. 1986, NVAG2 (Paris, June 1988; Schertzer and Lovejoy, 1991, five consecutive annual sessions at EGS general assemblies and two consecutive spring AGU meeting sessions. As with the other conferences and workshops mentioned above, the aim was to develop confrontation between theories and experiments on scaling/multifractal behaviour of geophysical fields. Subjects covered included climate, clouds, earthquakes, atmospheric and ocean dynamics, tectonics, precipitation, hydrology, the solar cycle and volcanoes. Areas of focus included new methods of data analysis (especially those used for the reliable estimation of multifractal and scaling exponents, as well as their application to rapidly growing data bases from in situ networks and remote sensing. The corresponding modelling, prediction and estimation techniques were also emphasized as were the current debates about stochastic and deterministic dynamics, fractal geometry and multifractals, self-organized criticality and multifractal fields, each of which was the subject of a specific general discussion. The conference started with a one day short course of multifractals featuring four lectures on a Fundamentals of multifractals: dimension, codimensions, codimension formalism, b Multifractal estimation techniques: (PDMS, DTM, c Numerical simulations, Generalized Scale Invariance analysis, d Advanced multifractals, singular statistics, phase transitions, self-organized criticality and Lie cascades (given by D. Schertzer and S. Lovejoy, detailed course notes were sent to participants shortly after the

  6. EGS Richardson AGU Chapman NVAG3 Conference: Nonlinear Variability in Geophysics: scaling and multifractal processes

    Science.gov (United States)

    Schertzer, D.; Lovejoy, S.

    1. The conference The third conference on "Nonlinear VAriability in Geophysics: scaling and multifractal processes" (NVAG 3) was held in Cargese, Corsica, Sept. 10-17, 1993. NVAG3 was joint American Geophysical Union Chapman and European Geophysical Society Richardson Memorial conference, the first specialist conference jointly sponsored by the two organizations. It followed NVAG1 (Montreal, Aug. 1986), NVAG2 (Paris, June 1988; Schertzer and Lovejoy, 1991), five consecutive annual sessions at EGS general assemblies and two consecutive spring AGU meeting sessions. As with the other conferences and workshops mentioned above, the aim was to develop confrontation between theories and experiments on scaling/multifractal behaviour of geophysical fields. Subjects covered included climate, clouds, earthquakes, atmospheric and ocean dynamics, tectonics, precipitation, hydrology, the solar cycle and volcanoes. Areas of focus included new methods of data analysis (especially those used for the reliable estimation of multifractal and scaling exponents), as well as their application to rapidly growing data bases from in situ networks and remote sensing. The corresponding modelling, prediction and estimation techniques were also emphasized as were the current debates about stochastic and deterministic dynamics, fractal geometry and multifractals, self-organized criticality and multifractal fields, each of which was the subject of a specific general discussion. The conference started with a one day short course of multifractals featuring four lectures on a) Fundamentals of multifractals: dimension, codimensions, codimension formalism, b) Multifractal estimation techniques: (PDMS, DTM), c) Numerical simulations, Generalized Scale Invariance analysis, d) Advanced multifractals, singular statistics, phase transitions, self-organized criticality and Lie cascades (given by D. Schertzer and S. Lovejoy, detailed course notes were sent to participants shortly after the conference). This

  7. Characterising and modelling regolith stratigraphy using multiple geophysical techniques

    Science.gov (United States)

    Thomas, M.; Cremasco, D.; Fotheringham, T.; Hatch, M. A.; Triantifillis, J.; Wilford, J.

    2013-12-01

    Regolith is the weathered, typically mineral-rich layer from fresh bedrock to land surface. It encompasses soil (A, E and B horizons) that has undergone pedogenesis. Below is the weathered C horizon that retains at least some of the original rocky fabric and structure. At the base of this is the lower regolith boundary of continuous hard bedrock (the R horizon). Regolith may be absent, e.g. at rocky outcrops, or may be many 10's of metres deep. Comparatively little is known about regolith, and critical questions remain regarding composition and characteristics - especially deeper where the challenge of collecting reliable data increases with depth. In Australia research is underway to characterise and map regolith using consistent methods at scales ranging from local (e.g. hillslope) to continental scales. These efforts are driven by many research needs, including Critical Zone modelling and simulation. Pilot research in South Australia using digitally-based environmental correlation techniques modelled the depth to bedrock to 9 m for an upland area of 128 000 ha. One finding was the inability to reliably model local scale depth variations over horizontal distances of 2 - 3 m and vertical distances of 1 - 2 m. The need to better characterise variations in regolith to strengthen models at these fine scales was discussed. Addressing this need, we describe high intensity, ground-based multi-sensor geophysical profiling of three hillslope transects in different regolith-landscape settings to characterise fine resolution (i.e. a number of frequencies; multiple frequency, multiple coil electromagnetic induction; and high resolution resistivity. These were accompanied by georeferenced, closely spaced deep cores to 9 m - or to core refusal. The intact cores were sub-sampled to standard depths and analysed for regolith properties to compile core datasets consisting of: water content; texture; electrical conductivity; and weathered state. After preprocessing (filtering, geo

  8. Estimation of Supraglacial Dust and Debris Geochemical Composition via Satellite Reflectance and Emissivity

    Science.gov (United States)

    Casey, Kimberly Ann; Kaab, Andreas

    2012-01-01

    We demonstrate spectral estimation of supraglacial dust, debris, ash and tephra geochemical composition from glaciers and ice fields in Iceland, Nepal, New Zealand and Switzerland. Surface glacier material was collected and analyzed via X-ray fluorescence spectroscopy (XRF) and X-ray diffraction (XRD) for geochemical composition and mineralogy. In situ data was used as ground truth for comparison with satellite derived geochemical results. Supraglacial debris spectral response patterns and emissivity-derived silica weight percent are presented. Qualitative spectral response patterns agreed well with XRF elemental abundances. Quantitative emissivity estimates of supraglacial SiO2 in continental areas were 67% (Switzerland) and 68% (Nepal), while volcanic supraglacial SiO2 averages were 58% (Iceland) and 56% (New Zealand), yielding general agreement. Ablation season supraglacial temperature variation due to differing dust and debris type and coverage was also investigated, with surface debris temperatures ranging from 5.9 to 26.6 C in the study regions. Applications of the supraglacial geochemical reflective and emissive characterization methods include glacier areal extent mapping, debris source identification, glacier kinematics and glacier energy balance considerations.

  9. Estimation of Supraglacial Dust and Debris Geochemical Composition via Satellite Reflectance and Emissivity

    Directory of Open Access Journals (Sweden)

    Kimberly Casey

    2012-09-01

    Full Text Available We demonstrate spectral estimation of supraglacial dust, debris, ash and tephra geochemical composition from glaciers and ice fields in Iceland, Nepal, New Zealand and Switzerland. Surface glacier material was collected and analyzed via X-ray fluorescence spectroscopy (XRF and X-ray diffraction (XRD for geochemical composition and mineralogy. In situ data was used as ground truth for comparison with satellite derived geochemical results. Supraglacial debris spectral response patterns and emissivity-derived silica weight percent are presented. Qualitative spectral response patterns agreed well with XRF elemental abundances. Quantitative emissivity estimates of supraglacial SiO2 in continental areas were 67% (Switzerland and 68% (Nepal, while volcanic supraglacial SiO2 averages were 58% (Iceland and 56% (New Zealand, yielding general agreement. Ablation season supraglacial temperature variation due to differing dust and debris type and coverage was also investigated, with surface debris temperatures ranging from 5.9 to 26.6 C in the study regions. Applications of the supraglacial geochemical reflective and emissive characterization methods include glacier areal extent mapping, debris source identification, glacier kinematics and glacier energy balance considerations.

  10. Use of partial dissolution techniques in geochemical exploration

    Science.gov (United States)

    Chao, T.T.

    1984-01-01

    Application of partial dissolution techniques to geochemical exploration has advanced from an early empirical approach to an approach based on sound geochemical principles. This advance assures a prominent future position for the use of these techniques in geochemical exploration for concealed mineral deposits. Partial dissolution techniques are classified as single dissolution or sequential multiple dissolution depending on the number of steps taken in the procedure, or as "nonselective" extraction and as "selective" extraction in terms of the relative specificity of the extraction. The choice of dissolution techniques for use in geochemical exploration is dictated by the geology of the area, the type and degree of weathering, and the expected chemical forms of the ore and of the pathfinding elements. Case histories have illustrated many instances where partial dissolution techniques exhibit advantages over conventional methods of chemical analysis used in geochemical exploration. ?? 1984.

  11. Methodological approaches in estimating anomalous geochemical field structure

    International Nuclear Information System (INIS)

    Gavrilov, R; Rudmin, M

    2015-01-01

    Mathematical statistic methods were applied to analyze the core samples from vertical expendable wells in Chertovo Koryto gold ore field. The following methods were used to analyse gold in samples: assay tests and atomic absorption method (AAS), while emission spectrum semiquantative method was applied to identify traces. The analysis of geochemical association distribution in one central profile demonstrated that bulk metasomatic aureoles are characteristic of concentric zonal structure. The distribution of geochemical associations is correlated to the hydrothermal stages of mineral formation identified in this deposit. It was proved that the processed geochemical data by factor and cluster analyses provided additional information on the anomalous geochemical field structure in gold- bearing black-shale strata. Such methods are effective tools in interpretating specific features of geochemical field structures in analogous potential ore-bearing areas

  12. INEL cold test pit demonstration of improvements in information derived from non-intrusive geophysical methods over buried waste sites

    International Nuclear Information System (INIS)

    1994-01-01

    Under contract between US DOE Idaho National Engineering Laboratory (INEL) and the Blackhawk Geosciences Division of Coleman Research Corporation (BGD-CRC), geophysical investigations were conducted to improve the detection of buried wastes. Over the Cold Test Pit (CTP) at INEL, data were acquired with multiple sensors on a dense grid. Over the CTP the interpretations inferred from geophysical data are compared with the known placement of various waste forms in the pit. The geophysical sensors employed were magnetics, frequency and time domain electromagnetics, and ground penetrating radar. Also, because of the high data density acquired, filtering and other data processing and imaging techniques were tested. After completion and analysis of the survey and interpretation over the CTP, the second phase of investigation consisted of testing geophysical methods over the Idaho Chemical Processing Plant (ICPP). The sections of the ICPP surveyed are underlain by a complex network of buried utility lines of different dimensions and composition, and with placement at various depths up to 13 ft. Further complications included many metallic objects at the surface, such as buildings, reinforced concrete pads, and debris. Although the multiple geophysical sensor approach mapped many buried utilities, they mapped far from all utilities shown on the facility drawings. This report consists of data collected from these geophysical surveys over the ICPP

  13. Evaluation and combined geophysical interpretations of NURE and related geoscience data in the Van Horn, Pecos, Marfa, Fort Stockton, Presidido, and Emory Peak quadrangles, Texas. Volume 1. Final report

    International Nuclear Information System (INIS)

    Keller, G.R.; Hinze, W.J.; Aiken, C.L.V.; Goodell, P.C.; Roy, R.F.; Pingitore, N.E.

    1981-09-01

    This report (two volumes) is the culmination of a two-year study of the six Trans-Pecos Texas quadrangles (Van Horn, Pecos, Marfa, Fort Stockton, Presidio, and Emory Park) surveyed as part of the National Uranium Resource Evaluation (NURE) program. Volume I contains a discussion of the aeromagnetic, gravity and geochemical data, their processing, and their analysis. The geologic history and setting of the Trans-Pecos are discussed along with the uranium potential of the region. Uranium anomalies and occurrences characteristic of numerous different NURE classes are present in the study area, and information is presented on 33 drill holes into these targets. Volume II is a folio of maps reduced to a scale of 1:500,000. Geologic maps for each of the six quadrangles are included and the geophysical maps have been prepared to be overlays for the goelogic maps. In addition to the geologic maps, residual aeromagnetic anomaly, complete Bouguer gravity anomaly, flight line index, gravity station index, and anomaly interpretative maps were prepared for each quadrangle. A large suite of digitally processed maps of gravity and aeromagnetic data were prepared and are included in Volume II

  14. Solid state nuclear track detection: a useful geological/geophysical tool

    International Nuclear Information System (INIS)

    Khan, H.A.; Qureshi, A.A.

    1994-01-01

    Solid State Nuclear Track Detection (SSNTD) is a relatively new nuclear particle detection technique. Since its inception, it has found useful application in almost every branch of science. This paper gives a very brief review of the role it has played in solving some geological/geophysical problems. Since the technique has been found useful in a wide spectrum of geological/geophysical applications, it was simply not possible to discuss all of these in this paper due to severe space restrictions. However, an attempt has been made to discuss the salient features of some of the most prominent applications in the geological and geophysical sciences. The paper has been divided into two parts. Firstly, applications based on radon measurements by SSNTDs have been described. These include: Uranium/thorium and mineral exploration, search for geothermal energy sources, study of volcanic processes, location of geological faults and earthquake prediction, for example. Secondly, applications based on the study of spontaneous fission tracks in geological samples have been described briefly. The second group of applications includes: fission track dating (FTD) of geological samples, FTD in the study of emplacement times, provenance studies, and thermal histories of minerals. Necessary references have been provided for detailed studies of (a) the applications cited in this paper, and (b) other important geological/geophysical applications, which unfortunately could not be covered in the present paper. (author)

  15. Combined interpretation of multiple geophysical techniques: an archaeological case study

    Science.gov (United States)

    Riedl, S.; Reichmann, S.; Tronicke, J.; Lück, E.

    2009-04-01

    In order to locate and ascertain the dimensions of an ancient orangery, we explored an area of about 70 m x 60 m in the Rheinsberg Palace Garden (Germany) with multiple geophysical techniques. The Rheinsberg Park, situated about 100 km northwest of Berlin, Germany, was established by the Prussian emperors in the 18th century. Due to redesign of the architecture and the landscaping during the past 300 years, buildings were dismantled and detailed knowledge about some original buildings got lost. We surveyed an area close to a gazebo where, after historical sources, an orangery was planned around the year 1740. However, today it is not clear to what extent this plan has been realized and if remains of this building are still buried in the subsurface. Applied geophysical techniques include magnetic gradiometry, frequency domain electromagnetic (FDEM) and direct current (DC) resistivity mapping as well as ground penetrating radar (GPR). To get an overview of the site, we performed FDEM electrical conductivity mapping using an EM38 instrument and magnetic gradiometry with caesium magnetometers. Both data sets were collected with an in- and crossline data point spacing of ca. 10 cm and 50 cm, respectively. DC resistivity surveying was performed using a pole-pole electrode configuration with an electrode spacing of 1.5 m and a spacing of 1.0 m between individual readings. A 3-D GPR survey was conducted using 200 MHz antennae and in- and crossline spacing of ca. 10 cm and 40 cm, respectively. A standard processing sequence including 3-D migration was applied. A combined interpretation of all collected data sets illustrates that the magnetic gradient and the EM38 conductivity maps is are dominated by anomalies from metallic water pipes from belonging to the irrigation system of the park. The DC resistivity map outlines a rectangular area which might indicate the extension of a former building south of the gazebo. The 3-D GPR data set provides further insights about

  16. Extreme drought decouples silicon and carbon geochemical linkages in lakes.

    Science.gov (United States)

    Li, Tianyang; Li, Siyue; Bush, Richard T; Liang, Chuan

    2018-09-01

    Silicon and carbon geochemical linkages were usually regulated by chemical weathering and organism activity, but had not been investigated under the drought condition, and the magnitude and extent of drought effects remain poorly understood. We collected a comprehensive data set from a total of 13 sampling sites covering the main water body of the largest freshwater lake system in Australia, the Lower Lakes. Changes to water quality during drought (April 2008-September 2010) and post-drought (October 2010-October 2013) were compared to reveal the effects of drought on dissolved silica (DSi) and bicarbonate (HCO 3 - ) and other environmental factors, including sodium (Na + ), pH, electrical conductivity (EC), chlorophyll a (Chl-a), total dissolved solids (TDS), dissolved inorganic nitrogen (DIN), total nitrogen (TN), total phosphorus (TP) and water levels. Among the key observations, concentrations of DSi and DIN were markedly lower in drought than in post-drought period while pH, EC and concentrations of HCO 3 - , Na + , Chl-a, TDS, TN, TP and the ratio TN:TP had inverse trends. Stoichiometric ratios of DSi:HCO 3 - , DSi:Na + and HCO 3 - :Na + were significantly lower in the drought period. DSi exhibited significantly negative relationships with HCO 3 - , and DSi:Na + was strongly correlated with HCO 3 - :Na + in both drought and post-drought periods. The backward stepwise regression analysis that could avoid multicollinearity suggested that DSi:HCO 3 - ratio in drought period had significant relationships with fewer variables when compared to the post-drought, and was better predictable using nutrient variables during post-drought. Our results highlight the drought effects on variations of water constituents and point to the decoupling of silicon and carbon geochemical linkages in the Lower Lakes under drought conditions. Copyright © 2018 Elsevier B.V. All rights reserved.

  17. Petrographic and geochemical characteristics of the Cypress Creek salt core

    International Nuclear Information System (INIS)

    1983-07-01

    Law Engineering Testing Company supervised the drilling of a corehole into the stock of Cypress Creek Dome, located in Perry County, Mississippi. A total of 170 ft of caprock and 501 ft of salt stock was recovered for physical examination and chemical analysis. This report describes the types of analyses performed and summarizes the data developed. The entire caprock and salt core were described and photographed prior to selection of samples for petrologic and geochemical analysis. Transmitted light techniques were used to determine gross structural and compositional variations in the core. The core lithologies are presented graphically, at a scale of 1 in. to 2 ft. In addition to the detailed field descriptions and photographs, petrologic studies performed on selected caprock and salt samples included: thin-section examination, scanning-electron microscope studies, energy-dispersion analysis, and x-ray-diffraction analysis. Geochemical analyses were performed to determine the average elemental composition of the salt core and amounts of methane and carbon dioxide gases contained within the salt grains. Except for two thin (3 and 6 ft thick) gypsum zones in the top 27 ft of the caprock, the core is predominantly anhydrite (generally 80%). Minor amounts of dolomite and calcite are also present. The salt core consists predominantly of crystalline halite, fine- to medium-grained (0.25 to 1 in.) with few megacrysts. Anhydrite occurs in the salt core as disseminated grains, ranging in length from <0.1 in. to 12 in. Discrete zones exist within the salt core, distinguished from one another primarily by the character of the anhydrite inclusions

  18. Geochemical investigation of UMTRAP designated site at Grand Junction, Colorado

    International Nuclear Information System (INIS)

    Markos, G.; Bush, K.J.

    1983-09-01

    This report is the result of a geochemical investigation of the former uranium mill and tailings site at Grand Junction, Colorado. The objectives of the investigation are to characterize the geochemistry, to determine the contaminant distribution resulting from the former milling activities and tailings, and to infer chemical pathways and transport mechanisms from the contaminant distribution. The results should be used to model contaminant migration and to develop criteria for long-term containment media, such as a cover system which is impermeable to contaminant migration. This report assumes a familiarity with the hydrologic conditions of the site and the geochemical concepts underlying the investigation. The results reported are based on a sampling of waters in two seasons and solid material from the background, the area adjacent to the site, and the site. The solid samples were water extracted to remove easily soluble salts and acid extracted to remove carbonates and hydroxides. The water extracts and solid samples were analyzed for the major and trace elements. A limited number of samples were analyzed for radiological components. The report includes the methods of sampling, sample processing, analysis, and data interpretation. Four major conclusions are: (1) trace element concentrations in shallow subsurface waters adjacent to the tailings temporally vary up to an order of magnitude; (2) the riverbank soils and borehole waters are contaminated with uranium, radium, and trace elements from discharge of tailings solids and solutions during the active time of the mill; however, the movement of contaminants toward the Colorado River does not appear to be significant; (3) the Colorado River adjacent to the tailings is not contaminated; and (4) trace metals have accumulated at both the tailings/cover and tailings/soil interface because of precipitation reactions caused by chemical differences between the two materials

  19. Results of detailed ground geophysical surveys for locating and differentiating waste structures in waste management area 'A' at Chalk River Laboratories, Ontario

    International Nuclear Information System (INIS)

    Tomsons, D.K.; Street, P.J.; Lodha, G.S.

    1999-01-01

    Waste Management Area 'A' (WMA 'A'), located in the outer area of the Chalk River Laboratories (CRL) was in use as a waste burial site from 1946 to 1955. Waste management structures include debris-filled trenches, concrete bunkers and miscellaneous contaminated solid materials, and ditches and pits used for liquid dispersal. In order to update historical records, it was proposed to conduct detailed ground geophysical surveys to define the locations of waste management structures in WMA 'A', assist in planning of the drilling and sampling program to provide ground truth for the geophysics investigation and to predict the nature and locations of unknown/undefined shallow structures. A detailed ground geophysical survey grid was established with a total of 127 grid lines, oriented NNE and spaced one metre apart. The geophysical surveys were carried out during August and September, 1996. The combination of geophysical tools used included the Geonics EM61 metal detector, the GSM-19 magnetometer/gradiometer and a RAMAC high frequency ground penetrating radar system. The geophysical surveys were successful in identifying waste management structures and in characterizing to some extent, the composition of the waste. The geophysical surveys are able to determine the presence of most of the known waste management structures, especially in the western and central portions of the grid which contain the majority of the metallic waste. The eastern portion of the grid has a completely different geophysical character. While historical records show that trenches were dug, they are far less evident in the geophysical record. There is clear evidence for a trench running between lines 30E and 63E at 70 m. There are indications from the radar survey of other trench-like structures in the eastern portion. EM61 data clearly show that there is far less metallic debris in the eastern portion. The geophysical surveys were also successful in identifying previously unknown locations of waste

  20. GEOCHEMICAL CONTROLS ON NUCLEAR MAGNETIC RESONANCE MEASUREMENTS

    International Nuclear Information System (INIS)

    Knight, Rosemary

    2008-01-01

    Proton nuclear magnetic resonance (NMR) is used in the Earth Sciences as a means of obtaining information about the molecular-scale environment of fluids in porous geological materials. Laboratory experiments were conducted to advance our fundamental understanding of the link between the NMR response and the geochemical properties of geological materials. In the first part of this research project, we studied the impact of both the surface-area-to-volume ratio (S/V) of the pore space and the surface relaxivity on the NMR response of fluids in sand-clay mixtures. This study highlighted the way in which these two parameters control our ability to use NMR measurements to detect and quantify fluid saturation in multiphase saturated systems. The second part of the project was designed to explore the way in which the mineralogic form of iron, as opposed to simply the concentration of iron, affects the surface relaxation rate and, more generally, the NMR response of porous materials. We found that the magnitude of the surface relaxation rate was different for the various iron-oxide minerals because of changes in both the surface-area-to-volume ratio of the pore space, and the surface relaxivity. Of particular significance from this study was the finding of an anomalously large surface relaxivity of magnetite compared to that of the other iron minerals. Differences in the NMR response of iron minerals were seen in column experiments during the reaction of ferrihydrite-coated quartz sand with aqueous Fe(II) solutions to form goethite, lepidocrocite and magnetite; indicating the potential use of NMR as a means of monitoring geochemical reactions. The final part of the research project investigated the impact of heterogeneity, at the pore-scale, on the NMR response. This work highlighted the way in which the geochemistry, by controlling the surface relaxivity, has a significant impact on the link between NMR data and the microgeometry of the pore space.

  1. Geochemical studies on island arc volcanoes

    International Nuclear Information System (INIS)

    Notsu, Kenji

    1998-01-01

    This paper summarizes advances in three topics of geochemical studies on island arc volcanoes, which I and my colleagues have been investigating. First one is strontium isotope studies of arc volcanic rocks mainly from Japanese island arcs. We have shown that the precise spatial distribution of the 87 Sr/ 86 Sr ratio reflects natures of the subduction structure and slab-mantle interaction. Based on the 87 Sr/ 86 Sr ratio of volcanic rocks in the northern Kanto district, where two plates subduct concurrently with different directions, the existence of an aseismic portion of the Philippine Sea plate ahead of the seismic one was suggested. Second one is geochemical monitoring of active arc volcanoes. 3 He/ 4 He ratio of volcanic volatiles was shown to be a good indicator to monitor the behavior of magma: ascent and drain-back of magma result in increase and decrease in the ratio, respectively. In the case of 1986 eruptions of Izu-Oshima volcano, the ratio began to increase two months after big eruptions, reaching the maximum and decreased. Such delayed response is explained in terms of travelling time of magmatic helium from the vent area to the observation site along the underground steam flow. Third one is remote observation of volcanic gas chemistry of arc volcanoes, using an infrared absorption spectroscopy. During Unzen eruptions starting in 1990, absorption features of SO 2 and HCl of volcanic gas were detected from the observation station at 1.3 km distance. This was the first ground-based remote detection of HCl in volcanic gas. In the recent work at Aso volcano, we could identify 5 species (CO, COS, CO 2 , SO 2 and HCl) simultaneously in the volcanic plume spectra. (author)

  2. Applications of geophysics to LLRW sites

    International Nuclear Information System (INIS)

    Olhoeft, G.R.

    1984-01-01

    There are many geophysical techniques which noninvasively acquire information about hazardous waste sites. Waste buried in metal drums can be located using magnetic and electromagnetic methods. Ground penetrating radar can provide detailed cross-sectional imagery of the ground to locate metallic and nonmetallic objects, and to delineate water tables and geologic structure. Complex resistivity can locate clay horizons or clay liners and detect organic reactions that may increase the permeability of the clay. Seismic refraction and reflection techniques can detail hydrology and stratigraphy. Microgravity techniques can find local density anomalies that may indicate voids or future subsidence problems. Radiometric techniques can directly detect near-surface radioisotope migration. Nothing works all the time, however. Magnetics cannot detect a badly corroded drum. Complex resistivity cannot detect clay-organic reactions if there are no clays. Ground penetrating radar cannot penetrate high conductivity or high clay content soils. Seismic cannot penetrate loose fill. Each technique has advantages and disadvantages inherent to the method and equipment as well as limitations imposed by the geohydrology at the site of application. Examples from both the Radioactive Waste and Hazardous Chemical Waste programs illustrate the advantages and disadvantages of geophysical methods

  3. Spatial and temporal distribution of geophysical disasters

    Directory of Open Access Journals (Sweden)

    Cvetković Vladimir

    2013-01-01

    Full Text Available Natural disasters of all kinds (meteorological, hydrological, geophysical, climatological and biological are increasingly becoming part of everyday life of modern human. The consequences are often devastating, to the life, health and property of people, as well to the security of states and the entire international regions. In this regard, we noted the need for a comprehensive investigation of the phenomenology of natural disasters. In addition, it is particularly important to pay attention to the different factors that might correlate with each other to indicate more dubious and more original facts about their characteristics. However, as the issue of natural disasters is very wide, the subject of this paper will be forms, consequences, temporal and spatial distribution of geophysical natural disasters, while analysis of other disasters will be the subject of our future research. Using an international database on natural disasters of the centre for research on the epidemiology of disasters (CRED based in Brussels, with the support of the statistical analysis (SPSS, we tried to point out the number, trends, consequences, the spatial and temporal distribution of earthquakes, volcanic eruptions and dry mass movements in the world, from 1900 to 2013.

  4. Geophysical logging for mineral exploration and development

    International Nuclear Information System (INIS)

    Plouffe, R.D.

    1981-01-01

    It is possible to retrieve from small-diameter holes geophysical data for qualitative interpretation in exploration and quantitative interpretation in the development of orebodies. The primary objectives in the exploration stage are to identify where, within a hole, economic minerals are, and to help in lithological interpretations. Other aspects, which are more quantitative, are the interpretation of downhole logs for parameters which can be used in surface geophysical methods (i.e. density for gravity surveys, acoustic velocities for seismic surveys, and magnetic susceptibility for airborne and ground magnetic surveys). Recent advances in equipment design, portability and durability have made downhole logging in exploration more inexpensive and reliable. This new equipment is being used to generate very precise quantitative results. This is especially true on uranium development projects. The interpretation of gamma logs for eU 3 O 8 values has finally become precise enough that they have begun to replace chemical values in reserve calculations. Another part of development data is density and equilibrium information, which, with today's technology, is being derived from downhole probing. In the years to come, the trends for many metals are toward neutron activation techniques, or in-situ assaying, and the use of multiple logs for better lithological and physical rock property determinations. (auth)

  5. Geophysical methods for monitoring soil stabilization processes

    Science.gov (United States)

    Saneiyan, Sina; Ntarlagiannis, Dimitrios; Werkema, D. Dale; Ustra, Andréa

    2018-01-01

    Soil stabilization involves methods used to turn unconsolidated and unstable soil into a stiffer, consolidated medium that could support engineered structures, alter permeability, change subsurface flow, or immobilize contamination through mineral precipitation. Among the variety of available methods carbonate precipitation is a very promising one, especially when it is being induced through common soil borne microbes (MICP - microbial induced carbonate precipitation). Such microbial mediated precipitation has the added benefit of not harming the environment as other methods can be environmentally detrimental. Carbonate precipitation, typically in the form of calcite, is a naturally occurring process that can be manipulated to deliver the expected soil strengthening results or permeability changes. This study investigates the ability of spectral induced polarization and shear-wave velocity for monitoring calcite driven soil strengthening processes. The results support the use of these geophysical methods as soil strengthening characterization and long term monitoring tools, which is a requirement for viable soil stabilization projects. Both tested methods are sensitive to calcite precipitation, with SIP offering additional information related to long term stability of precipitated carbonate. Carbonate precipitation has been confirmed with direct methods, such as direct sampling and scanning electron microscopy (SEM). This study advances our understanding of soil strengthening processes and permeability alterations, and is a crucial step for the use of geophysical methods as monitoring tools in microbial induced soil alterations through carbonate precipitation.

  6. SIGKit: Software for Introductory Geophysics Toolkit

    Science.gov (United States)

    Kruse, S.; Bank, C. G.; Esmaeili, S.; Jazayeri, S.; Liu, S.; Stoikopoulos, N.

    2017-12-01

    The Software for Introductory Geophysics Toolkit (SIGKit) affords students the opportunity to create model data and perform simple processing of field data for various geophysical methods. SIGkit provides a graphical user interface built with the MATLAB programming language, but can run even without a MATLAB installation. At this time SIGkit allows students to pick first arrivals and match a two-layer model to seismic refraction data; grid total-field magnetic data, extract a profile, and compare this to a synthetic profile; and perform simple processing steps (subtraction of a mean trace, hyperbola fit) to ground-penetrating radar data. We also have preliminary tools for gravity, resistivity, and EM data representation and analysis. SIGkit is being built by students for students, and the intent of the toolkit is to provide an intuitive interface for simple data analysis and understanding of the methods, and act as an entrance to more sophisticated software. The toolkit has been used in introductory courses as well as field courses. First reactions from students are positive. Think-aloud observations of students using the toolkit have helped identify problems and helped shape it. We are planning to compare the learning outcomes of students who have used the toolkit in a field course to students in a previous course to test its effectiveness.

  7. Isotopic and geochemical tracers in the evaluation of groundwater residence time and salinization problems at Santiago Island, Cape Verde

    International Nuclear Information System (INIS)

    Carreira, Paula M.; Nunes, Dina; Marques, Jose M.; Monteiro Santos, Fernando A.; Goncalves, Rui; Pina, Antonio; Mota Gomes, Antonio

    2013-01-01

    Stable isotopes (δ 18 O, δ 2 H) and tritium ( 3 H), together with geochemistry and geophysical data, were used for evaluating groundwater recharge sources, flow paths, and residence times in a watershed on Santiago Island, Cape Verde, West Africa. Stable isotopes indicate the predominance of high-elevation precipitation that undergoes little evaporation prior to groundwater recharge. Low tritium concentrations at seven sampling sites indicate groundwater residence times greater than 50 years. Higher tritium values at other locations suggest more recent recharge. Young ages indicate local recharge and potential groundwater vulnerability to surface contamination and/or salt-water intrusion. Geochemical results indicate that water-rock interaction mechanisms are the major processes responsible for the groundwater quality (mainly calcium-bicarbonate type), reflecting the lithological composition of subsurface soil. (authors)

  8. Isotopic and geochemical tracers in the evaluation of groundwater residence time and salinization problems at Santiago Island, Cape Verde

    Energy Technology Data Exchange (ETDEWEB)

    Carreira, Paula M.; Nunes, Dina [Quimica Analitica e Ambiental, IST/ITN, Universidade Tecnica de Lisboa, Estrada Nacional no. 10, 2686-953 Sacavem (Portugal); Marques, Jose M. [Centro de Petrologia e Geoquimica. Instituto Superior Tecnico, UTL, Av. Rovisco Pais, 1049-001 Lisboa (Portugal); Monteiro Santos, Fernando A. [Universidade de Lisboa-IDL, 1749-016 Lisboa (Portugal); Goncalves, Rui [Inst. Politecnico de Tomar, Quinta do Contador, Estrada da Serra, 2300 Tomar (Portugal); Pina, Antonio; Mota Gomes, Antonio [Instituto Superior de Educacao, Praia, Santiago (Cape Verde)

    2013-07-01

    Stable isotopes (δ{sup 18}O, δ{sup 2}H) and tritium ({sup 3}H), together with geochemistry and geophysical data, were used for evaluating groundwater recharge sources, flow paths, and residence times in a watershed on Santiago Island, Cape Verde, West Africa. Stable isotopes indicate the predominance of high-elevation precipitation that undergoes little evaporation prior to groundwater recharge. Low tritium concentrations at seven sampling sites indicate groundwater residence times greater than 50 years. Higher tritium values at other locations suggest more recent recharge. Young ages indicate local recharge and potential groundwater vulnerability to surface contamination and/or salt-water intrusion. Geochemical results indicate that water-rock interaction mechanisms are the major processes responsible for the groundwater quality (mainly calcium-bicarbonate type), reflecting the lithological composition of subsurface soil. (authors)

  9. Geochemical orientation for mineral exploration in the Hashemite Kingdom of Jordan

    Science.gov (United States)

    Overstreet, W.C.; Grimes, D.J.; Seitz, J.F.

    1982-01-01

    This report is a supplement to previous accounts of geochemical exploration conducted in the Hashemite Kingdom of Jordan by the Natural Resources Authority of the Royal Government of Jordan and the U.S. Geological Survey. The field work on which this report is based was sponsored by the U.S. Agency for International Development, U.S. Department of State. Procedures used in collecting various kinds of rocks, ores, slags, eluvial and alluvial sediments, heavy-mineral concentrates, and organic materials for use as geochemical sample media are summarized, as are the laboratory procedures followed for the analysis of these sample materials by semiquantitative spectrographic, atomic absorption, fluorometric, and X-ray diffraction methods. Geochemical evaluations of the possibilities for economic mineral deposits in certain areas are presented. The results of these preliminary investigations open concepts for further use in geochemical exploration in the search for metallic mineral deposits in Jordan. Perhaps the most desirable new activity would be hydrogeochemical exploration for uranium and base metals, accompanied by interpretation of such remote-sensing data as results of airborne radiometric surveys and computer-enhanced LANDSAT imagery. For more conventional approaches to geochemical exploration, however, several fundamental problems regarding proper choice of geochemical sample media for different geologic and geographic parts of the Country must be solved before effective surveys can be made. The present results also show that such common geochemical exploration techniques as the determination of the trace-element contents of soils, plant ash, and slags have direct application also toward the resolution of several archaeological problems in Jordan. These include the relation of trace-elements chemistry of local soils to the composition of botanic remains, the trace-elements composition of slags to the technological development of the extractive metallurgy of

  10. Overview of the geochemical code MINTEQ: applications to performance assessment for low-level wastes

    International Nuclear Information System (INIS)

    Graham, M.J.; Peterson, S.R.

    1985-09-01

    The MINTEQ geochemical computer code, developed at Pacific Northwest Laboratory, integrates many of the capabilities of its two immediate predecessors, WATEQ3 and MINEQL. MINTEQ can be used to perform the calculations necessary to simulate (model) the contact of low-level waste solutions with heterogeneous sediments or the interaction of ground water with solidified low-level wastes. The code is capable of performing calculations of ion speciation/solubility, adsorption, oxidation-reduction, gas phase equilibria, and precipitation/dissolution of solid phases. Under the Special Waste Form Lysimeters-Arid program, the composition of effluents (leachates) from column and batch experiments, using laboratory-scale waste forms, will be used to develop a geochemical model of the interaction of ground water with commercial solidified low-level wastes. The wastes being evaluated include power reactor waste streams that have been solidified in cement, vinyl ester-styrene, and bitumen. The thermodynamic database for the code is being upgraded before the geochemical modeling is performed. Thermodynamic data for cobalt, antimony, cerium, and cesium solid phases and aqueous species are being added to the database. The need to add these data was identified from the characterization of the waste streams. The geochemical model developed from the laboratory data will then be applied to predict the release from a field-lysimeter facility that contains full-scale waste samples. The contaminant concentrations migrating from the wastes predicted using MINTEQ will be compared to the long-term lysimeter data. This comparison will constitute a partical field validation of the geochemical model. 28 refs

  11. A Geochemical Reaction Model for Titration of Contaminated Soil and Groundwater at the Oak Ridge Reservation

    Science.gov (United States)

    Zhang, F.; Parker, J. C.; Gu, B.; Luo, W.; Brooks, S. C.; Spalding, B. P.; Jardine, P. M.; Watson, D. B.

    2007-12-01

    This study investigates geochemical reactions during titration of contaminated soil and groundwater at the Oak Ridge Reservation in eastern Tennessee. The soils and groundwater exhibits low pH and high concentrations of aluminum, calcium, magnesium, manganese, various trace metals such as nickel and cobalt, and radionuclides such as uranium and technetium. The mobility of many of the contaminant species diminishes with increasing pH. However, base additions to increase pH are strongly buffered by various precipitation/dissolution and adsorption/desorption reactions. The ability to predict acid-base behavior and associated geochemical effects is thus critical to evaluate remediation performance of pH manipulation strategies. This study was undertaken to develop a practical but generally applicable geochemical model to predict aqueous and solid-phase speciation during soil and groundwater titration. To model titration in the presence of aquifer solids, an approach proposed by Spalding and Spalding (2001) was utilized, which treats aquifer solids as a polyprotic acid. Previous studies have shown that Fe and Al-oxyhydroxides strongly sorb dissolved Ni, U and Tc species. In this study, since the total Fe concentration is much smaller than that of Al, only ion exchange reactions associated with Al hydroxides are considered. An equilibrium reaction model that includes aqueous complexation, precipitation, ion exchange, and soil buffering reactions was developed and implemented in the code HydroGeoChem 5.0 (HGC5). Comparison of model results with experimental titration curves for contaminated groundwater alone and for soil- water systems indicated close agreement. This study is expected to facilitate field-scale modeling of geochemical processes under conditions with highly variable pH to develop practical methods to control contaminant mobility at geochemically complex sites.

  12. An overview of the geochemical code MINTEQ: Applications to performance assessment for low-level wastes

    International Nuclear Information System (INIS)

    Peterson, S.R.; Opitz, B.E.; Graham, M.J.; Eary, L.E.

    1987-03-01

    The MINTEQ geochemical computer code, developed at the Pacific Northwest Laboratory (PNL), integrates many of the capabilities of its two immediate predecessors, MINEQL and WATEQ3. The MINTEQ code will be used in the Special Waste Form Lysimeters-Arid program to perform the calculations necessary to simulate (model) the contact of low-level waste solutions with heterogeneous sediments of the interaction of ground water with solidified low-level wastes. The code can calculate ion speciation/solubilitya, adsorption, oxidation-reduction, gas phase equilibria, and precipitation/dissolution of solid phases. Under the Special Waste Form Lysimeters-Arid program, the composition of effluents (leachates) from column and batch experiments, using laboratory-scale waste forms, will be used to develop a geochemical model of the interaction of ground water with commercial, solidified low-level wastes. The wastes being evaluated include power-reactor waste streams that have been solidified in cement, vinyl ester-styrene, and bitumen. The thermodynamic database for the code was upgraded preparatory to performing the geochemical modeling. Thermodynamic data for solid phases and aqueous species containing Sb, Ce, Cs, or Co were added to the MINTEQ database. The need to add these data was identified from the characterization of the waste streams. The geochemical model developed from the laboratory data will then be applied to predict the release from a field-lysimeter facility that contains full-scale waste samples. The contaminant concentrations migrating from the waste forms predicted using MINTEQ will be compared to the long-term lysimeter data. This comparison will constitute a partial field validation of the geochemical model

  13. Comments on geochemical aspects of SR 97

    International Nuclear Information System (INIS)

    Arthur, R.C.; Wei Zhou

    2000-01-01

    The Swedish Government has asked SKB to carry out a safety assessment of the KBS-3 disposal concept for spent nuclear fuel 'to demonstrate that the KBS-3 method has good prospects of being able to meet the safety and radiation protection requirements which SKI and SSI have specified in recent years.' The results of that assessment, referred to as SR 97, have recently been published. The present report summarizes the results of a review of selected geochemical aspects of SR 97. These subjects include the hydrochemical evolution of a defective canister, thermodynamic data supporting estimates of radioelement solubilities, modeling of near-field chemistry and analyses of the effects of ice melting on propagation of an oxidizing front to repository depths. The primary focus of the review is on the canister-defect scenario, and, more specifically, on supporting analyses of the hydromechanical evolution of a defective canister. The results of these analyses figure prominently in the safety assessment because they suggest that even a defective canister will, in effect, remain dry for as long as 200,000 years. This is an important constraint because it is taken in SR 97 as the period of time required for a continuous water pathway to form in the near field. The transport of most radionuclides (i.e., those that do not exist as a gas) cannot occur until this pathway is formed. It is concluded that although SKBs hydromechanical models are sound, they may suffer from an over-simplification of the chemical processes involved. Analyses using the models do not acknowledge that the chemical system within the canister is open in all respects to the chemical system in the buffer. Instead, mass transfer across the defect at the canister-buffer interface is limited to liquid H 2 O and water vapor. Consideration of mass transfer of other gases [e.g., CO 2 and H 2 S] dissolved in buffer porewaters suggests that associated reactions involving the iron insert and inner surfaces of the

  14. REVIEW ARTICLE: Geophysical signatures of oceanic core complexes

    Science.gov (United States)

    Blackman, Donna K.; Canales, J. Pablo; Harding, Alistair

    2009-08-01

    Oceanic core complexes (OCCs) provide access to intrusive and ultramafic sections of young lithosphere and their structure and evolution contain clues about how the balance between magmatism and faulting controls the style of rifting that may dominate in a portion of a spreading centre for Myr timescales. Initial models of the development of OCCs depended strongly on insights available from continental core complexes and from seafloor mapping. While these frameworks have been useful in guiding a broader scope of studies and determining the extent of OCC formation along slow spreading ridges, as we summarize herein, results from the past decade highlight the need to reassess the hypothesis that reduced magma supply is a driver of long-lived detachment faulting. The aim of this paper is to review the available geophysical constraints on OCC structure and to look at what aspects of current models are constrained or required by the data. We consider sonar data (morphology and backscatter), gravity, magnetics, borehole geophysics and seismic reflection. Additional emphasis is placed on seismic velocity results (refraction) since this is where deviations from normal crustal accretion should be most readily quantified. However, as with gravity and magnetic studies at OCCs, ambiguities are inherent in seismic interpretation, including within some processing/analysis steps. We briefly discuss some of these issues for each data type. Progress in understanding the shallow structure of OCCs (within ~1 km of the seafloor) is considerable. Firm constraints on deeper structure, particularly characterization of the transition from dominantly mafic rock (and/or altered ultramafic rock) to dominantly fresh mantle peridotite, are not currently in hand. There is limited information on the structure and composition of the conjugate lithosphere accreted to the opposite plate while an OCC forms, commonly on the inside corner of a ridge-offset intersection. These gaps preclude full

  15. Oman Drilling Project Phase I Borehole Geophysical Survey

    Science.gov (United States)

    Matter, J. M.; Pezard, P. A.; Henry, G.; Brun, L.; Célérier, B.; Lods, G.; Robert, P.; Benchikh, A. M.; Al Shukaili, M.; Al Qassabi, A.

    2017-12-01

    holes BT1, GT3 and BA2 due to hole obstruction (e.g. collapsed borehole wall). Results from the geophysical survey including preliminary log analysis will be presented for each OmanDP Phase I borehole.

  16. Solar Wind Monitor--A School Geophysics Project

    Science.gov (United States)

    Robinson, Ian

    2018-01-01

    Described is an established geophysics project to construct a solar wind monitor based on a nT resolution fluxgate magnetometer. Low-cost and appropriate from school to university level it incorporates elements of astrophysics, geophysics, electronics, programming, computer networking and signal processing. The system monitors the earth's field in…

  17. Rožňava ore field - geophysical works

    Directory of Open Access Journals (Sweden)

    Géczy Július

    1998-12-01

    Full Text Available The article prowides a review of geophysical works in the ore field Rožňava conducted up to date. Magnetometric and geoelectric methods and gravimetric measurements have been used. Geophysical works were focused to the solving regional problems whose contribution to the prospecting of vein deposits is not essential.

  18. Technical Note: Calibration and validation of geophysical observation models

    NARCIS (Netherlands)

    Salama, M.S.; van der Velde, R.; van der Woerd, H.J.; Kromkamp, J.C.; Philippart, C.J.M.; Joseph, A.T.; O'Neill, P.E.; Lang, R.H.; Gish, T.; Werdell, P.J.; Su, Z.

    2012-01-01

    We present a method to calibrate and validate observational models that interrelate remotely sensed energy fluxes to geophysical variables of land and water surfaces. Coincident sets of remote sensing observation of visible and microwave radiations and geophysical data are assembled and subdivided

  19. Comparison study of selected geophysical and geotechnical parameters

    DEFF Research Database (Denmark)

    Nissen, Randi Warncke; Poulsen, Søren Erbs

    Successful foundation of constructions relies on accurate characterization of the geotechnical properties of the subsurface. By implementing data from geophysical surveys, the placement of geotechnical drillings can be significantly improved, potentially reducing the number of required drillings....... This case study is mainly to compare geophysical investigations (MEP/IP) with existing PACES data and information from geotechnical drillings....

  20. Strategies for improving the resolution of electrical and electromagnetic geophysical measurements for three-dimensional inverse modeling of CO2 movement

    Science.gov (United States)

    Commer, M.; Kowalsky, M. B.; Dafflon, B.; Wu, Y.; Hubbard, S. S.

    2013-12-01

    Geologic carbon sequestration is being evaluated as a means to mitigate the effects of greenhouse gas emissions. Efforts are underway to identify adequate reservoirs and to evaluate the behavior of injected CO2 over time; time-lapse geophysical methods are considered effective tools for these purposes. Pilot studies have shown that the invasion of CO2 into a background pore fluid can alter the electrical resistivity, with increases from CO2 in the super-critical or gaseous phase, and decreases from CO2 dissolved in groundwater (especially when calcite dissolution is occurring). Because of their sensitivity to resistivity changes, electrical and electromagnetic (EM) methods have been used in such studies for indirectly assessing CO2 saturation changes. While the electrical resistance tomography (ERT) method is a well-established technique for both crosswell and surface applications, its usefulness is limited by the relatively low-resolution information it provides. Controlled-source EM methods, including both frequency-domain and time-domain (transient EM) methods, can offer improved resolution. We report on three studies that aim to maximize the information content of electrical and electromagnetic measurements in inverse modeling applications that target the monitoring of resistivity changes due to CO2 migration and/or leakage. The first study considers a three-dimensional crosswell data set collected at an analogue site used for investigating CO2 distribution and geochemical reactivity within a shallow formation. We invert both resistance and phase data using a gradient-weighting method for descent-based inversion algorithms. This method essentially steers the search direction in the model space using low-cost non-linear conjugate gradient methods towards the more computationally expensive Gauss-Newton direction. The second study involves ERT data that were collected at the SECARB Cranfield site near Natchez, Mississippi, at depths exceeding 3000 m. We employ a

  1. Multivariate time series clustering on geophysical data recorded at Mt. Etna from 1996 to 2003

    Science.gov (United States)

    Di Salvo, Roberto; Montalto, Placido; Nunnari, Giuseppe; Neri, Marco; Puglisi, Giuseppe

    2013-02-01

    Time series clustering is an important task in data analysis issues in order to extract implicit, previously unknown, and potentially useful information from a large collection of data. Finding useful similar trends in multivariate time series represents a challenge in several areas including geophysics environment research. While traditional time series analysis methods deal only with univariate time series, multivariate time series analysis is a more suitable approach in the field of research where different kinds of data are available. Moreover, the conventional time series clustering techniques do not provide desired results for geophysical datasets due to the huge amount of data whose sampling rate is different according to the nature of signal. In this paper, a novel approach concerning geophysical multivariate time series clustering is proposed using dynamic time series segmentation and Self Organizing Maps techniques. This method allows finding coupling among trends of different geophysical data recorded from monitoring networks at Mt. Etna spanning from 1996 to 2003, when the transition from summit eruptions to flank eruptions occurred. This information can be used to carry out a more careful evaluation of the state of volcano and to define potential hazard assessment at Mt. Etna.

  2. Joint inversion of geophysical data for site characterization and restoration monitoring. 1998 annual progress report

    International Nuclear Information System (INIS)

    Berge, P.A.; Berryman, J.G.; Roberts, J.J.; Wildenschild, D.

    1998-01-01

    'The purpose of this project is to develop a computer code for joint inversion of seismic and electrical data, to improve underground imaging for site characterization and remediation monitoring. The computer code developed in this project will invert geophysical data to obtain direct estimates of porosity and saturation underground, rather than inverting for seismic velocity and electrical resistivity or other geophysical properties. This is intended to be a significant improvement in the state-of-the-art of underground imaging, since interpretation of data collected at a contaminated site would become much less subjective. Potential users include DOE scientists and engineers responsible for characterizing contaminated sites and monitoring remediation of contaminated sites. In this three-year project, the authors use a multi-phase approach consisting of theoretical and numerical code development, laboratory investigations, testing on available laboratory and borehole geophysics data sets, and a controlled field experiment, to develop practical tools for joint electrical and seismic data interpretation. This report summarizes work after about 1.7 years of a 3-year project. Progress on laboratory measurements is described first, followed by progress on developing algorithms for the inversion code to relate geophysical data to porosity and saturation.'

  3. Establishing geochemical background levels of selected trace elements in areas having geochemical anomalies: The case study of the Orbetello lagoon (Tuscany, Italy)

    International Nuclear Information System (INIS)

    Romano, Elena; Bergamin, Luisa; Croudace, Ian W.; Ausili, Antonella; Maggi, Chiara; Gabellini, Massimo

    2015-01-01

    The determination of background concentration values (BGVs) in areas, characterised by the presence of natural geochemical anomalies and anthropogenic impact, appears essential for a correct pollution assessment. For this purpose, it is necessary to establish a reliable method for determination of local BGVs. The case of the Orbetello lagoon, a geologically complex area characterized by Tertiary volcanism, is illustrated. The vertical concentration profiles of As, Cd, Cr, Cu, Hg, Ni, Pb and Zn were studied in four sediment cores. Local BGVs were determined considering exclusively samples not affected by anthropogenic influence, recognized by means of multivariate statistics and radiochronological dating ( 137 Cs and 210 Pb). Results showed BGVs well-comparable with mean crustal or shale values for most of the considered elements except for Hg (0.87 mg/kg d.w.) and As (16.87 mg/kg d.w.), due to mineralization present in the catchment basin draining into the lagoon. - Highlights: • Pollution assessment in areas with geochemical anomalies needs local reference values. • A new method for the determination of background values (BGV) was established. • Geochemical data from unpolluted samples of sediment cores were used. • Statistics and geochronology were applied to recognize unpolluted sediments. • Anthropogenically influenced samples were not considered for BGV determination. - A method including multivariate statistics and radiochronological dating is proposed for determining local background values for trace elements using analytical data form sediment cores

  4. The Importance of Mars Samples in Constraining the Geological and Geophysical Processes on Mars and the Nature of its Crust, Mantle, and Core

    Science.gov (United States)

    iMOST Team; Herd, C. D. K.; Ammannito, E.; Anand, M.; Debaille, V.; Hallis, L. J.; McCubbin, F. M.; Schmitz, N.; Usui, T.; Weiss, B. P.; Altieri, F.; Amelin, Y.; Beaty, D. W.; Benning, L. G.; Bishop, J. L.; Borg, L. E.; Boucher, D.; Brucato, J. R.; Busemann, H.; Campbell, K. A.; Carrier, B. L.; Czaja, A. D.; Des Marais, D. J.; Dixon, M.; Ehlmann, B. L.; Farmer, J. D.; Fernandez-Remolar, D. C.; Fogarty, J.; Glavin, D. P.; Goreva, Y. S.; Grady, M. M.; Harrington, A. D.; Hausrath, E. M.; Horgan, B.; Humayun, M.; Kleine, T.; Kleinhenz, J.; Mangold, N.; Mackelprang, R.; Mayhew, L. E.; McCoy, J. T.; McLennan, S. M.; McSween, H. Y.; Moser, D. E.; Moynier, F.; Mustard, J. F.; Niles, P. B.; Ori, G. G.; Raulin, F.; Rettberg, P.; Rucker, M. A.; Sefton-Nash, E.; Sephton, M. A.; Shaheen, R.; Shuster, D. L.; Siljestrom, S.; Smith, C. L.; Spry, J. A.; Steele, A.; Swindle, T. D.; ten Kate, I. L.; Tosca, N. J.; Van Kranendonk, M. J.; Wadhwa, M.; Werner, S. C.; Westall, F.; Wheeler, R. M.; Zipfel, J.; Zorzano, M. P.

    2018-04-01

    We present the main sample types from any potential Mars Sample Return landing site that would be required to constrain the geological and geophysical processes on Mars, including the origin and nature of its crust, mantle, and core.

  5. MINTEQ, Geochemical Equilibria in Ground Water

    International Nuclear Information System (INIS)

    Krupka, K.M.

    1990-01-01

    1 - Description of program or function: MINTEQ is a geochemical program to model aqueous solutions and the interactions of aqueous solutions with hypothesized assemblages of solid phases. It was developed for the Environmental Protection Agency to perform the calculations necessary to simulate the contact of waste solutions with heterogeneous sediments or the interaction of ground water with solidified wastes. MINTEQ can calculate ion speciation/solubility, adsorption, oxidation-reduction, gas phase equilibria, and precipitation/dissolution of solid phases. MINTEQ can accept a finite mass for any solid considered for dissolution and will dissolve the specified solid phase only until its initial mass is exhausted. This ability enables MINTEQ to model flow-through systems. In these systems the masses of solid phases that precipitate at earlier pore volumes can be dissolved at later pore volumes according to thermodynamic constraints imposed by the solution composition and solid phases present. The ability to model these systems permits evaluation of the geochemistry of dissolved traced metals, such as low-level waste in shallow land burial sites. MINTEQ was designed to solve geochemical equilibria for systems composed of one kilogram of water, various amounts of material dissolved in solution, and any solid materials that are present. Systems modeled using MINTEQ can exchange energy and material (open systems) or just energy (closed systems) with the surrounding environment. Each system is composed of a number of phases. Every phase is a region with distinct composition and physically definable boundaries. All of the material in the aqueous solution forms one phase. The gas phase is composed of any gaseous material present, and structurally distinct solid forms a separate phase. 2 - Method of solution: MINTEQ applies the fundamental principles of thermodynamics to solve geochemical equilibria from a set of mass balance equations, one for each component. Because the

  6. Geology, alteration, mineralization, petrogenesis, geochronology, geochemistry and airborne geophysics of Kuh Shah prospecting area, SW Birjand

    Directory of Open Access Journals (Sweden)

    Maryam Abdi

    2012-04-01

    Full Text Available The Kuh Shah prospecting area is located in Tertiary volcano-plutonic belt of the Lut Block. More than seventeen subvolcanic intermediate to acidic intrusive rocks, diorite to syenite in composition, were identified in the study area. The intrusions are related to hydrothermal alteration zones and contain argillic, propylitic, advanced argillic, silicified, quartz-sericite-pyrite, gossan and hydrothermal breccia which overprinted to each other and are accompanied by weathering which made it complicated to distinguish zoning. Mineralization is observed as sulfide (pyrite and rare chalcopyrite, disseminated Fe-oxides and quartz-Fe-oxide stockwork veinlets. Intrusive rocks are metaluminous, calc-alkaline with shoshonitic affinity with high values of magnetic susceptibility. The Kuh Shah intrusive rocks are classified as magnetite-series of oxidant I-type granitoids. Based on zircon U–Pb age dating, the age of these granitoid rocks is 39.7± 0.7 Ma (Middle Eocene. The radioisotope data (initial 87Sr/86Sr and 143Nd/144Nd ratios as well as εNd and geochemical data suggest that the Kuh Shah granitoid rocks formed from depleted mantle in a subduction-related magmatic arc setting. Geochemical anomalies of elements such as Cu, Au, Fe, Pb, Zn, As, Sb, Mo, Bi, Hg and also Mn, Ba, Te and Se, correlated with quartz-sericite-pyrite, gossan-stockwork-hydrothermal breccias, irregular silicified bodies and advanced argillic hydrothermal alteration zones. Geophysical anomalies correlated with hydrothermal alteration and mineralization zones. The interpretation of the results represents complex patterns of sub-circular to ellipsoid shape with north-east to south-west direction. These evidences are similar to the other for known Cu-Au porphyry and Au-epithermal systems in Iran and worldwide.

  7. Water-Energy-Food Nexus: Compelling Issues for Geophysical Research

    Science.gov (United States)

    Akhbari, M.; Grigg, N. S.; Waskom, R.

    2014-12-01

    The joint security of water, food, and energy systems is an urgent issue everywhere, and strong drivers of development and land use change, exacerbated by climate change, require new knowledge to achieve integrated solution using a nexus-based approach to assess inter-dependencies. Effective research-based decision support tools are essential to identify the major issues and interconnections to help in implementation of the nexus approach. The major needs are models and data to clearly and unambiguously present decision scenarios to local cooperative groups of farmers, electric energy generators and water officials for joint decisions. These can be developed by integrated models to link hydrology, land use, energy use, cropping simulation, and optimization with economic objectives and socio-physical constraints. The first step in modeling is to have a good conceptual model and then to get data. As the linking of models increases uncertainties, each one should be supplied with adequate data at suitable spatial and temporal resolutions. Most models are supplied with data by geophysical scientists, such as hydrologists, geologists, atmospheric scientists, soil scientists, and climatologists, among others. Outcomes of a recently-completed project to study the water-energy-food nexus will be explained to illuminate the model and data needs to inform future management actions across the nexus. The project included a workshop of experts from government, business, academia, and the non-profit sector who met to define and explain nexus interactions and needs. An example of the findings is that data inconsistencies among sectors create barriers to integrated planning. A nexus-based systems model is needed to outline sectoral inter-dependencies and identify data demands and gaps. Geophysical scientists can help to create this model and take leadership on designing data systems to facilitate sharing and enable integrated management.

  8. Temporal associations of life with solar and geophysical activity

    Directory of Open Access Journals (Sweden)

    T. K. Breus

    Full Text Available In biology, circadian rhythms with a period of one cycle in 20–28 h are known to be ubiquitous and partly endogenous. Rhythms with a frequency lower than one cycle per day are called 'infradian rhythms'. Among them are components with one cycle in about 3.5, 7, 14 and 28 days, the multiseptans, which, like the circadians, must be regarded as a general characteristic of life: they characterize unicells as well as much more differentiated organisms. We hypothesize that heliogeophysical factors other than the solar visible light, held responsible for the evolution of circadian periodicity, underlie the infradian rhythms of biosystems. The periodicities in the solar wind and variations in the interplanetary magnetic field (IMF which are associated with the solar rotation are very similar in length to the biological periodicities. We investigate the temporal relations of variations in solar activity and in biological systems to test associations between events in the IMF, in geomagnetic disturbance, in myocardial infarction and in physiology. By cross-spectral analysis, we also find relations at certain frequencies between changes in human physiology on the one hand, and (1 the vertical component of the induction vector of the IMF, Bz, and (2 a global index of geomagnetic disturbance, Kp, on the other hand. We wish to stimulate interest in these periodicities of both biological systems and geophysical endpoints among physicists and biologists alike, so that problems relevant to clinicians and other biologists, including evolutionists, are eventually solved by their cooperation with the geophysical community.

  9. Geophysical surveys at the UMTRA project Shiprock, New Mexico site

    International Nuclear Information System (INIS)

    Wightman, E.; Smith, B.; Newlin, B.

    1996-03-01

    Geophysical surveys were performed at the Uranium Mill Tailings Remedial Action (UMTRA) Shiprock site in New Mexico during February 1996. The surveys were designed to locate areas of ground water contamination, consisting largely of sulfate and nitrate salts and uranium. Electrical geophysical methods were used to locate areas of sulfate and nitrate concentrations since these products, when present in ground water, increase its electrical conductivity. These contaminants also increase the density of water, making the water with the highest concentrations of these salts sink to the bottom of the water column. At the Shiprock site, where alluvium is underlain by the impervious Mancos Shale, the saline water will tend to rest in depressions on the shale surface. Seismic refraction surveys were conducted on the floodplain. The site comprises two areas, the terrace and the floodplain, separated by a steep scarp of some 70 feet (ft) (20 meters [m]). Measurements of electrical conductivity were taken over these two areas, searching for possible pockets of saline ground water resting on top of the bedrock. Conductivity surveys were also run to identify fractures within the bedrock that may act as conduits for ground water movement. Several areas of higher than normal conductivity were found on the terrace, including halos of higher conductivities on three sides of the tailings cell. The conductivity measurements searching for fractures found only a small number of minor fracture-like anomalies. These are not considered important. On the floodplain, both conductivity and seismic refraction measurements were taken. The conductivity measurements clearly show areas of high conductivity interpreted to result from ground water contamination. The seismic refraction measurements identified bedrock depressions that may contain denser, and more saline ground water lenses. Generally, the areas of high conductivity coincide with the bedrock depressions

  10. Multigroup neutron data base for nuclear geophysics

    International Nuclear Information System (INIS)

    Dworak, D.; Loskiewicz, J.

    1989-01-01

    The average group constants for the total, elastic, inelastic and capture cross sections as well as the average cosine of the scattering angle for elastic scattering and the average logarithmic energy decrement for elastic scattering have been obtained at two temperatures (300 and 400 deg K), using the ENDF/B-4 data and the IAEA-NDS pre-processing codes. The extended Abagyan group structure and the weighting spectrum of type 1/E were applied in course of the calculations. Self-shielding effect was not taken into account. All cross sections were Doppler broadened for both, 300 and 400 deg K temperatures. Under above assumptions, the average group constants were obtained for exactly 22 ENDF materials, which are of special importance for nuclear geophysics applications. 10 refs., 15 figs., 44 tabs. (author)

  11. Geophysical examinations of deposits and old sites

    International Nuclear Information System (INIS)

    1991-01-01

    Geomagnetic total field measurements by proton magnetometers with memories form the systematic exploration of suspected surfaces of old sites and old sites of an important, flexible and reasonably priced geophysical process. From experience, there are two important main applications. These are firstly the detailed work on location problems jointly with and supplementing multi-temporal evaluations of the air picture and secondly to locate iron in deposits. The particular advantage of geo-magnetics is that even in the most difficult measurement conditions, with the aid of the suitable analytical method evaluation, clear results and practically usable information can be obtained. In comparison with this, other high resolution methods of measurement, such as electromagnetic charting, for example (problem of integral anomaly pictures which cannot be evaluated) and geo-radar (loam covering, trickled water saturation) are limited to a considerably narrower measurement and evaluation spectrum in practical applications. (orig.) [de

  12. Avalanches in functional materials and geophysics

    CERN Document Server

    Saxena, Avadh; Planes, Antoni

    2017-01-01

    This book provides the state-of-the art of the present understanding of avalanche phenomena in both functional materials and geophysics. The main emphasis of the book is analyzing these apparently different problems within the common perspective of out-of-equilibrium phenomena displaying spatial and temporal complexity that occur in a broad range of scales. Many systems, when subjected to an external force, respond intermittently in the form of avalanches that often span over a wide range of sizes, energies and durations. This is often related to a class of critical behavior characterized by the absence of characteristic scales. Typical examples are magnetization processes, plastic deformation and failure occuring in functional materials. These phenomena share many similarities with seismicity arising from the earth crust failure due to stresses that originate from plate tectonics.

  13. Geophysical characterization of contaminated muddy sediments

    International Nuclear Information System (INIS)

    McDermott, I. R.; English, G. E.

    1997-01-01

    A non-intrusive, seismic subbottom profile survey of pond sediments was conducted on a former U.S.Naval Facility at Argentia, Newfoundland, to characterize the nature and extent of contamination. An IKB Seistec boomer was used in conjunction with C-CORE's HI-DAPT digital data acquisition and processing system and differential GPS system. The survey was successful in locating regions of soft muddy sediments and in determining the thickness of these deposits. Subsurface buried objects, which are potential sources of pollution, were also identified. Intrusive profiling of the sediment was done with a new tool, the Soil Stiffness Probe, which combines two geophysical measurement systems to determine bulk density and shear stiffness. The muddy sediments were found to be highly 'fluidized', indicating that they could be easily removed with a suction dredge. 4 refs., 5 figs

  14. Cosmic Muon Detection for Geophysical Applications

    Directory of Open Access Journals (Sweden)

    László Oláh

    2013-01-01

    Full Text Available A portable cosmic muon detector has been developed for environmental, geophysical, or industrial applications. The device is a tracking detector based on the Close Cathode Chamber, an MWPC-like technology, allowing operation in natural underground caves or artificial tunnels, far from laboratory conditions. The compact, low power consumption system with sensitive surface of 0.1 m2 measures the angular distribution of cosmic muons with a resolution of 10 mrad, allowing for a detailed mapping of the rock thickness above the muon detector. Demonstration of applicability of the muon telescope (REGARD Muontomograph for civil engineering and measurements in artificial underground tunnels or caverns are presented.

  15. Software complex for geophysical data visualization

    Science.gov (United States)

    Kryukov, Ilya A.; Tyugin, Dmitry Y.; Kurkin, Andrey A.; Kurkina, Oxana E.

    2013-04-01

    The effectiveness of current research in geophysics is largely determined by the degree of implementation of the procedure of data processing and visualization with the use of modern information technology. Realistic and informative visualization of the results of three-dimensional modeling of geophysical processes contributes significantly into the naturalness of physical modeling and detailed view of the phenomena. The main difficulty in this case is to interpret the results of the calculations: it is necessary to be able to observe the various parameters of the three-dimensional models, build sections on different planes to evaluate certain characteristics and make a rapid assessment. Programs for interpretation and visualization of simulations are spread all over the world, for example, software systems such as ParaView, Golden Software Surfer, Voxler, Flow Vision and others. However, it is not always possible to solve the problem of visualization with the help of a single software package. Preprocessing, data transfer between the packages and setting up a uniform visualization style can turn into a long and routine work. In addition to this, sometimes special display modes for specific data are required and existing products tend to have more common features and are not always fully applicable to certain special cases. Rendering of dynamic data may require scripting languages that does not relieve the user from writing code. Therefore, the task was to develop a new and original software complex for the visualization of simulation results. Let us briefly list of the primary features that are developed. Software complex is a graphical application with a convenient and simple user interface that displays the results of the simulation. Complex is also able to interactively manage the image, resize the image without loss of quality, apply a two-dimensional and three-dimensional regular grid, set the coordinate axes with data labels and perform slice of data. The

  16. Geophysical assessments of renewable gas energy compressed in geologic pore storage reservoirs.

    Science.gov (United States)

    Al Hagrey, Said Attia; Köhn, Daniel; Rabbel, Wolfgang

    2014-01-01

    Renewable energy resources can indisputably minimize the threat of global warming and climate change. However, they are intermittent and need buffer storage to bridge the time-gap between production (off peak) and demand peaks. Based on geologic and geochemical reasons, the North German Basin has a very large capacity for compressed air/gas energy storage CAES in porous saltwater aquifers and salt cavities. Replacing pore reservoir brine with CAES causes changes in physical properties (elastic moduli, density and electrical properties) and justify applications of integrative geophysical methods for monitoring this energy storage. Here we apply techniques of the elastic full waveform inversion FWI, electric resistivity tomography ERT and gravity to map and quantify a gradually saturated gas plume injected in a thin deep saline aquifer within the North German Basin. For this subsurface model scenario we generated different synthetic data sets without and with adding random noise in order to robust the applied techniques for the real field applications. Datasets are inverted by posing different constraints on the initial model. Results reveal principally the capability of the applied integrative geophysical approach to resolve the CAES targets (plume, host reservoir, and cap rock). Constrained inversion models of elastic FWI and ERT are even able to recover well the gradual gas desaturation with depth. The spatial parameters accurately recovered from each technique are applied in the adequate petrophysical equations to yield precise quantifications of gas saturations. Resulting models of gas saturations independently determined from elastic FWI and ERT techniques are in accordance with each other and with the input (true) saturation model. Moreover, the gravity technique show high sensitivity to the mass deficit resulting from the gas storage and can resolve saturations and temporal saturation changes down to ±3% after reducing any shallow fluctuation such as that of

  17. Coupling Flow & Transport Modeling with Electromagnetic Geophysics to Better Understand Crustal Permeability

    Science.gov (United States)

    Pepin, J.; Folsom, M.; Person, M. A.; Kelley, S.; Gomez-Velez, J. D.; Peacock, J.

    2016-12-01

    Over the last 30 years, considerable effort has focused on understanding the distribution of permeability within the earth's crust and its implications for flow and transport. The scarcity of direct observations makes the description of permeabilities beyond depths of about 3 km particularly challenging. Numerous studies have defined depth-decay relationships for basement permeability, while others note that it is too complex to be characterized by a general relationship. Hydrothermal modeling studies focusing on two geothermal systems within the tectonically active Rio Grande rift of New Mexico suggest that there may be laterally extensive regions of highly permeable (10-14 to 10-12 m2) basement rocks at depths ranging between 4 and 8 km. The NaCl groundwater signature, elevated fracture density, and secondary mineralization of fractured basement outcrops associated with these geothermal systems indicate that there may indeed be significant groundwater flow within the basement rocks of the rift. We hypothesize that there are extensive regions of highly permeable crystalline basement rocks at depths greater than 3 km within the Rio Grande rift. These fractured zones serve as large conduits for geothermal fluids before they ascend to shallow depths through gaps in overlying confining sediments or along faults. To test these hypotheses, we use a combination of geophysical observations and flow and transport modeling. We used electromagnetic geophysics (TEM & MT) to image resistivity in one of the hypothesized deep circulation geothermal systems near Truth or Consequences, NM. The resistivity dataset, in tandem with geochemical and thermal observations, is then used to calibrate a hydrothermal model of the system. This new calibration methodology has the potential to change the way researchers study crustal fluid flow and geothermal systems; thereby providing a tool to explore depths greater than 3 km where minimal data is available. In addition, it has the advantage

  18. Geochemical surveys in the Lusi mud eruption

    Science.gov (United States)

    Sciarra, Alessandra; Mazzini, Adriano; Etiope, Giuseppe; Inguaggiato, Salvatore; Hussein, Alwi; Hadi J., Soffian

    2016-04-01

    The Lusi mud eruption started in May 2006 following to a 6.3 M earthquake striking the Java Island. In the framework of the Lusi Lab project (ERC grant n° 308126) we carried out geochemical surveys in the Sidoarjo district (Eastern Java Island, Indonesia) to investigate the gas bearing properties of the Watukosek fault system that crosses the Lusi mud eruption area. Soil gas (222Rn, CO2, CH4) concentration and flux measurements were performed 1) along two detailed profiles (~ 1km long), trending almost W-E direction, and 2) inside the Lusi embankment (about 7 km2) built to contain the erupted mud. Higher gas concentrations and fluxes were detected at the intersection with the Watukosek fault and the antithetic fault system. These zones characterized by the association of higher soil gas values constitute preferential migration pathways for fluids towards surface. The fractures release mainly CO2 (with peaks up to 400 g/m2day) and display higher temperatures (up to 41°C). The main shear zones are populated by numerous seeps that expel mostly CH4. Flux measurements in the seeping pools reveal that φCO2 is an order of magnitude higher than that measured in the fractures, and two orders of magnitude higher for φCH4. An additional geochemical profile was completed perpendicularly to the Watukosek fault escarpement (W-E direction) at the foots of the Penanngungang volcano. Results reveal CO2 and CH4 flux values significantly lower than those measured in the embankment, however an increase of radon and flux measurements is observed approaching the foots of the escarpment. These measurements are complemented with a database of ~350 CH4 and CO2 flux measurements and some soil gas concentrations (He, H2, CO2, CH4 and C2H6) and their isotopic analyses (δ13C-CH4, δD-CH4 and δ13C-CO2). Results show that the whole area is characterized by diffused gas release through seeps, fractures, microfractures and soil degassing. The collected results shed light on the origin of the

  19. A New Social Contract for Geophysics

    Science.gov (United States)

    Malone, T. F.

    2002-12-01

    The Golden Age for geophysical research that followed the IGY set the stage for a new era of interaction among science, technology, and society. World population and the average economic productivity of individuals have both continued to grow exponentially during the past 50 years with the result that by the 1980s the demands of the human economy on the finite renewable resources of planet Earth were approximately equal to the natural regenerative capacities of planetary ecosystems. These demands are now "overshooting" those regenerative powers by about 20 per cent (1). The result could be a collapse in the life-supporting capacity of global ecosystems during coming decades, with tragic implications for civilized society. Novel modes of collaboration among all disciplines and all sectors of society are urgently needed to transform a potential catastrophe into the attractive vision that is now within reach as a result of rapidly expanding human knowledge, emerging technologies for sharing that knowledge (2), and the set of ethical principles for sustainable development contained in the Earth Charter (3). This prospect challenges geophysicists and scholars in all disciplines to forge a new and broadly based contract with society (4). 1. Wackernagel M. et al. 2002. "Tracking the ecological overshoot of the human economy." Proc. Natl. Acad. Sci. USA, Vol. 99, Issue 14, 9266-9271, July 9. 2. Malone T. and Yohe G. 2002. "Knowledge partnerships for a sustainable, equitable, and stable society." J. of Knowledge Management, Vol. 6, No. 4, October (in press). 3. www.earthcharter.org 4. Malone T. 1997. "Building on the legacies of the Intenational Geophysical Year." Transactions, AGU, Vol.78, No. 15, pp. 185-191.

  20. What's down below? Current and potential future applications of geophysical techniques to identify subsurface permafrost conditions (Invited)

    Science.gov (United States)

    Douglas, T. A.; Bjella, K.; Campbell, S. W.

    2013-12-01

    For infrastructure design, operations, and maintenance requirements in the North the ability to accurately and efficiently detect the presence (or absence) of ground ice in permafrost terrains is a serious challenge. Ground ice features including ice wedges, thermokarst cave-ice, and segregation ice are present in a variety of spatial scales and patterns. Currently, most engineering applications use borehole logging and sampling to extrapolate conditions at the point scale. However, there is high risk of over or under estimating the presence of frozen or unfrozen features when relying on borehole information alone. In addition, boreholes are costly, especially for planning linear structures like roads or runways. Predicted climate warming will provide further challenges for infrastructure development and transportation operations where permafrost degradation occurs. Accurately identifying the subsurface character in permafrost terrains will allow engineers and planners to cost effectively create novel infrastructure designs to withstand the changing environment. There is thus a great need for a low cost rapidly deployable, spatially extensive means of 'measuring' subsurface conditions. Geophysical measurements, both terrestrial and airborne, have strong potential to revolutionize our way of mapping subsurface conditions. Many studies in continuous and discontinuous permafrost have used geophysical measurements to identify discrete features and repeatable patterns in the subsurface. The most common measurements include galvanic and capacitive coupled resistivity, ground penetrating radar, and multi frequency electromagnetic induction techniques. Each of these measurements has strengths, weaknesses, and limitations. By combining horizontal geophysical measurements, downhole geophysics, multispectral remote sensing images, LiDAR measurements, and soil and vegetation mapping we can start to assemble a holistic view of how surface conditions and standoff measurements

  1. Geochemical geochronology and genesis of granite from Coronel Murta, Northeast of Minas Gerais, Brazil

    International Nuclear Information System (INIS)

    Soares, A.C.P.; Siga Junior, O.

    1987-01-01

    Geological, petrographic, geochemical (including rare-earth elements) and geochronological data of the Coronel Murta (Northeast Minas Gerais State) post-tectonic intrusive alkalic granites were summarized in order to discuss their genesis. This paper shows that Coronel Murta granites were generated by anatexis of dominantly metasedimentary rocks, in an ensialic environment, as the late results of an intraplate A-type subduction during the Brazilian Cycle. (author) [pt

  2. Uruguay mining inventory. Geochemical prospecting results of the Las Flores aerial map

    International Nuclear Information System (INIS)

    Zeegers, H.; Bonnefoy, D.; Garau, M.; Spangenberg, J.

    1981-01-01

    In the context of the Uruguay mining inventory, the aerial photography map Las Flores had been covered by a specific strategic which included geochemical prospecting elements. The surface covered has the 550 km2, and 1042 samples which they have been analized in Orleans France. 22 elements by plasma spectroscopy and gold by atomic absorption and for uranium laser spectroscopy . They have been evidenced the following anomalies: gold, Pb, Pb-Ba-Cu, Ba and Ni-Cr

  3. Contemporaneous deposition of phyllosilicates and sulfates: Using Australian acidic saline lake deposits to describe geochemical variability on Mars

    Science.gov (United States)

    Baldridge, A.M.; Hook, S.J.; Crowley, J.K.; Marion, G.M.; Kargel, J.S.; Michalski, J.L.; Thomson, B.J.; de Souza, Filho C.R.; Bridges, N.T.; Brown, A.J.

    2009-01-01

    Studies of the origin of the Martian sulfate and phyllosilicate deposits have led to the hypothesis that there was a marked, global-scale change in the Mars environment from circum-neutral pH aqueous alteration in the Noachian to an acidic evaporitic system in the late Noachian to Hesperian. However, terrestrial studies suggest that two different geochemical systems need not be invoked to explain such geochemical variation.Western Australian acidic playa lakes have large pH differences separated vertically and laterally by only a few tens of meters, demonstrating how highly variable chemistries can coexist over short distances in natural environments. We suggest diverse and variable Martian aqueous environments where the coetaneous formation of phyllosilicates and sulfates at the Australian sites are analogs for regions where phyllosilicates and sulfates coexist on Mars. In these systems, Fe and alkali earth phyllosilicates represent deep facies associated with upwelling neutral to alkaline groundwater, whereas aluminous phyllosilicates and sulfates represent near-surface evaporitic facies formed from more acidic brines. Copyright 2009 by the American Geophysical Union.

  4. Immersive, hands-on, team-based geophysical education at the University of Texas Marine Geology and Geophysics Field Course

    Science.gov (United States)

    Saustrup, S.; Gulick, S. P.; Goff, J. A.; Davis, M. B.; Duncan, D.; Reece, R.

    2013-12-01

    The University of Texas Institute for Geophysics (UTIG), part of the Jackson School of Geosciences, annually offers a unique and intensive three-week marine geology and geophysics field course during the spring/summer semester intersession. Now entering its seventh year, the course transitions students from a classroom environment through real-world, hands-on field acquisition, on to team-oriented data interpretation, culminating in a professional presentation before academic and industry employer representatives. The course is available to graduate students and select upper-division undergraduates, preparing them for direct entry into the geoscience workforce or for further academic study. Geophysical techniques used include high-resolution multichannel seismic reflection, CHIRP sub-bottom profiling, multibeam bathymetry, sidescan sonar, sediment coring, grab sampling, data processing, and laboratory analysis of sediments. Industry-standard equipment, methods, software packages, and visualization techniques are used throughout the course, putting students ahead of many of their peers in this respect. The course begins with a 3-day classroom introduction to the field area geology, geophysical methods, and computing resources used. The class then travels to the Gulf Coast for a week of hands-on field and lab work aboard two research vessels: UTIG's 22-foot, aluminum hulled Lake Itasca; and NOAA's 82-foot high-speed catamaran R/V Manta. The smaller vessel handles primarily shallow, inshore targets using multibeam bathymetry, sidescan sonar, and grab sampling. The larger vessel is used both inshore and offshore for multichannel seismic, CHIRP profiling, multibeam bathymetry, gravity coring, and vibracoring. Field areas to date have included Galveston and Port Aransas, Texas, and Grand Isle, Louisiana, with further work in Grand Isle scheduled for 2014. In the field, students work in teams of three, participating in survey design, instrument set-up, field deployment

  5. Prospect of Continuous VLBI Measurement of Earth Rotation in Monitoring Geophysical Fluids

    Science.gov (United States)

    Chao, Benjamin F.; Ma, Chopo; Clark, Thomas

    1998-01-01

    Large-scale mass transports in the geophysical fluids of the Earth system excite Earth's rotational variations in both length-of-day and polar motion. The excitation process is via the conservation of angular momentum. Therefore Earth rotation observations contain information about the integrated angular momentum (consisting of both the mass term and the motion term) of the geophysical fluids, which include atmosphere, hydrosphere, mantle, and the outer and inner cores. Such global information is often important and otherwise unattainable depending on the nature of the mass transport, its magnitude and time scale. The last few years have seen great advances in VLBI measurement of Earth rotation in precision and temporal resolution. These advances have opened new. areas in geophysical fluid studies, such as oceanic tidal angular momentum, atmospheric tides, Earth librations, and rapid atmospheric angular momentum fluctuations. Precision of 10 microseconds in UTI and 200 microarcseconds in polar motion can now be achieved on hourly basis. Building upon this heritage, the multi-network geodetic VLBI project, Continuous Observation of the Rotation of the Earth (CORE), promises to further these studies and to make possible studies on elusive but tell-tale geophysical processes such as oscillatory modes in the core and in the atmosphere. Currently the early phase of CORE is underway. Within a few years into the new mellinnium, the upcoming space gravity missions (such as GRACE) will measure the temporal variations in Earth's gravitational field, thus providing complementary information to that from Earth rotation study for a better understanding of global geophysical fluid processes.

  6. Geochemical modeling of magmatic gas scrubbing

    Directory of Open Access Journals (Sweden)

    B. Gambardella

    2005-06-01

    Full Text Available The EQ3/6 software package, version 7.2 was successfully used to model scrubbing of magmatic gas by pure water at 0.1 MPa, in the liquid and liquid-plus-gas regions. Some post-calculations were necessary to account for gas separation effects. In these post-calculations, redox potential was considered to be fixed by precipitation of crystalline a-sulfur, a ubiquitous and precocious process. As geochemical modeling is constrained by conservation of enthalpy upon water-gas mixing, the enthalpies of the gas species of interest were reviewed, adopting as reference state the liquid phase at the triple point. Our results confirm that significant emissions of highly acidic gas species (SO2(g, HCl(g, and HF(g are prevented by scrubbing, until dry conditions are established, at least locally. Nevertheless important outgassing of HCl(g can take place from acid, HCl-rich brines. Moreover, these findings support the rule of thumb which is generally used to distinguish SO2-, HCl-, and HF-bearing magmatic gases from SO2-, HCl-, and HF-free hydrothermal gases.

  7. Podoconiosis: non-infectious geochemical elephantiasis.

    Science.gov (United States)

    Davey, Gail; Tekola, Fasil; Newport, Melanie J

    2007-12-01

    This article reviews peer-reviewed publications and book chapters on the history, epidemiology, genetics, ecology, pathogenesis, pathology and management of podoconiosis (endemic non-filarial elephantiasis). Podoconiosis is a non-infectious geochemical elephantiasis caused by exposure of bare feet to irritant alkalic clay soils. It is found in at least 10 countries in tropical Africa, Central America and northwest India, where such soils coexist with high altitude, high seasonal rainfall and low income. Podoconiosis develops in men and women working barefoot on irritant soils, with signs becoming apparent in most patients by the third decade of life. Colloid-sized silicate particles appear to enter through the skin, are taken up into macrophages in the lower limb lymphatics and cause endolymphangitis and obliteration of the lymphatic lumen. Genetic studies provide evidence for high heritability of susceptibility to podoconiosis. The economic burden is significant in affected areas dependent on subsistence farming. Podoconiosis is unique in being an entirely preventable non-communicable disease. Primary prevention entails promoting use of footwear in areas of irritant soil; early stages are reversible given good foot hygiene, but late stages result in considerable economic and social difficulties, and require extended periods of elevation and occasionally nodulectomy.

  8. Petroleum geochemical responses to reservoir rock properties

    Energy Technology Data Exchange (ETDEWEB)

    Bennett, B.; Larter, S.R. [Calgary Univ., AB (Canada)

    2008-07-01

    Reservoir geochemistry is used to study petroleum basin development, petroleum mixing, and alterations. In this study, polar non-hydrocarbons were used as proxies for describing reservoir properties sensitive to fluid-rock interactions. A core flood experiment was conducted on a Carboniferous siltstone core obtained from a site in the United Kingdom. Core samples were then obtained from a typical upper shoreface in a North Sea oilfield. The samples were extracted with a dichloromethane and methanol mixture. Alkylcarbazoles and alkylfluorenones were then isolated from the samples. Compositional changes along the core were also investigated. Polar non hydrocarbons were studied using a wireline gamma ray log. The strongest deflections were observed in the basal coarsening upwards unit. The study demonstrated the correlations between molecular markers, and indicated that molecular parameters can be used to differentiate between clean sand units and adjacent coarsening upward muddy sand sequences. It was concluded that reservoir geochemical parameters can provide an independent response to properties defined by petrophysical methods. 6 refs., 2 figs.

  9. Geochemical prospect ion results of Mariscala aerial photo

    International Nuclear Information System (INIS)

    Filippini, J.

    1989-01-01

    This report shows the geochemical prospect ion results carried out within the framework of the metalical mining prospect ion in Mariscala aerial photo. Lavalleja district belong to the Mining inventory programme of Uruguay.

  10. Geochemical methodology for gold prospect ion in Uruguay

    International Nuclear Information System (INIS)

    Spangenber, J.

    1987-01-01

    This work is about the history of gold prospection in Uruguay. In this study there are considered the geochemical aspects, the gold performance, the applicability to mining prospection and the gold prospection aluvionar

  11. Drift pumice in the central Indian Ocean Basin: Geochemical evidence

    Digital Repository Service at National Institute of Oceanography (India)

    Pattan, J.N.; Mudholkar, A.V.; JaiSankar, S.; Ilangovan, D.

    Abundant white to light grey-coloured pumice without ferromanganese oxide coating occurs within the Quaternary sediments of the Central Indian Ocean Basin (CIOB). Two distinct groups of pumice are identified from their geochemical composition, which...

  12. National Geochemical Survey Locations and Results for Iowa

    Data.gov (United States)

    Iowa State University GIS Support and Research Facility — The United States Geological Survey (USGS), in collaboration with other state and federal agencies, industry, and academia, is conducting a National Geochemical...

  13. Uruguay mining Inventory: Geochemical prospecting results of Valentines mapping

    International Nuclear Information System (INIS)

    Spangenberg, J.; Filippini, J.

    1985-01-01

    This work is about geochemical prospecting carried out into the Uruguay mining inventory framework. In this case the survey was in Valentines mapping. Florida, Durazno and Treinta y Tres provinces of Uruguay .

  14. Chlorine isotopes potential as geo-chemical tracers

    Digital Repository Service at National Institute of Oceanography (India)

    Shirodkar, P.V.; Pradhan, U.K.; Banerjee, R.

    The potential of chlorine isotopes as tracers of geo-chemical processes of earth and the oceans is highlighted based on systematic studies carried out in understanding the chlorine isotope fractionation mechanism, its constancy in seawater and its...

  15. The geochemical chararateristics of the marble deposits east of ...

    African Journals Online (AJOL)

    ), marbles were investigated with the view to establishing marble occurrences and their geochemical characteristics. Crystalline rocks of the Nigerian Basement Complex (migmatite – gneiss complex) underlie the area. Ten marble bodies were ...

  16. Parts-based geophysical inversion with application to water flooding interface detection and geological facies detection

    Science.gov (United States)

    Zhang, Junwei

    data and prior distributions. We pose the geophysical inverse problem in terms of Gaussian random fields with mean functions controlled by petrophysical relationships and covariance functions controlled by a prior geological cross-section, including the definition of spatial boundaries for the geological facies. The petrophysical relationship problem is formulated as a regression problem upon each facies. The inversion is performed in a Bayesian framework. We demonstrate the usefulness of this strategy using a first synthetic case study, performing a joint inversion of gravity and galvanometric resistivity data with the stations all located at the ground surface. The joint inversion is used to recover the density and resistivity distributions of the subsurface. In a second step, we consider the possibility that the facies boundaries are deformable and their shapes are inverted as well. We use the level set approach to deform the facies boundaries preserving prior topological properties of the facies throughout the inversion. With the additional help of prior facies petrophysical relationships, topological characteristic of each facies, we make posterior inference about multiple geophysical tomograms based on their corresponding geophysical data misfits. The result of the inversion technique is encouraging when applied to a second synthetic case study, showing that we can recover the heterogeneities inside the facies, the mean values for the petrophysical properties, and, to some extent, the facies boundaries. A paper has been submitted to Geophysics on this topic and I am the first author of this paper. During this thesis, I also worked on the time lapse inversion problem of gravity data in collaboration with Marios Karaoulis and a paper was published in Geophysical Journal international on this topic. I also worked on the time-lapse inversion of cross-well geophysical data (seismic and resistivity) using both a structural approach named the cross-gradient approach and

  17. Geochemical, hydrological, and biological cycling of energy residual. Research plan

    International Nuclear Information System (INIS)

    Wobber, F.J.

    1983-03-01

    Proposed research goals and specific research areas designed to provide a base of fundamental scientific information so that the geochemical, hydrological, and biophysical mechanisms that contribute to the transport and long term fate of energy residuals in natural systems can be understood are described. Energy development and production have resulted in a need for advanced scientific information on the geochemical transformations, transport rates, and potential for bioaccumulation of contaminants in subsurface environments