Basalt stratigraphy - Pasco Basin

International Nuclear Information System (INIS)

Waters, A.C.; Myers, C.W.; Brown, D.J.; Ledgerwood, R.K.

1979-10-01

The geologic history of the Pasco Basin is sketched. Study of the stratigraphy of the area involved a number of techniques including major-element chemistry, paleomagnetic investigations, borehole logging, and other geophysical survey methods. Grande Ronde basalt accumulation in the Pasco Basin is described. An illustrative log response is shown. 1 figure

Geologic, stratigraphic, thermal, and mechanical factors which influence repository design in the bedded salt environment

International Nuclear Information System (INIS)

Ashby, J.P.; Nair, O.; Ortman, D.; Rowe, J.

1979-12-01

This report describes the geologic, stratigraphic, thermal, and mechanical considerations applicable to repository design. The topics discussed in the report include: tectonic activity; geologic structure; stratigraphy; rock mechanical properties; and hydrologic properties

Geohydrologic-engineering geology evaluation of the Selma Group in western Alabama and northeast Mississippi for possible radioactive waste disposal

International Nuclear Information System (INIS)

Gonzales, S.

1975-06-01

The following topics are discussed: regional stratigraphy, lithologic characteristic-chalk sequences, structural geology settting, earthquakes and historical seismicity, regional geomorphology, recovery of geological resources, and groundwater hydrology

Stratigraphy of the crater Copernicus

Science.gov (United States)

Paquette, R.

1984-01-01

The stratigraphy of copernicus based on its olivine absorption bands is presented. Earth based spectral data are used to develop models that also employ cratering mechanics to devise theories for Copernican geomorphology. General geologic information, spectral information, upper and lower stratigraphic units and a chart for model comparison are included in the stratigraphic analysis.

Stratigraphy and geologic age of the Neogene Shimajiri Group in Kumejima Island, Ryukyu Islands, southwestern Japan

International Nuclear Information System (INIS)

Nakamura, Yodai; Asahara, Yoshihiro; Ozawa, Tomowo; Kameo, Koji

1999-01-01

The Neogene Shimajiri Group is distributed sporadically in the Ryukyu islands. This study focuses on the Shimajiri Group in Kumejima Island, central Ryukyu, and clarifies its stratigraphy and geologic age on the basis of 1) lithostratigraphy, 2) calcareous nannofossil biostratigraphy, and 3) strontium isotope stratigraphy. The Shimajiri Group in Kumejima Island unconformably overlies the middle Miocene Aradake Formation, and is overlain by the Pleistocene Ryukyu Group. The group is divided into three formations, namely the Maja, the Aka and the Uegusukudake Formations in ascending order, and the first two are redefined in this paper based on the new geologic evidence. The Maja Formation consists mainly of fine-grained sandstone, sandy siltstone and alternating beds of them. The Aka Formation is mainly composed of cross-stratified sandstone, pumiceous sandstone and tuffaceous siltstone, and unconformably overlies the Maja Formation. The Uegusukudake Formation, conformably overlying the Aka Formation, consists of basaltic lava, tuff breccia and andesite. On the basis of calcareous nannofossil biostratigraphy, the Maja and Aka Formations can be assigned to Zone CN9 and Zone CN12b of Okada and Bukry (1980) respectively. Strontium isotope ages of the molluscan fossil specimens obtained from the Maja and Aka Formations revealed that the Maja Formation is assigned to the late Miocene (ca. 7.8-7.2 Ma) and the Aka Formation is assigned to the late Pliocene (ca. 3.2-3.1 Ma). These ages are concordant with the nannofossil biostratigraphy. The upper Miocene Maja Formation yields many molluscan fossils in which the characteristic species of the Kakegawa Fauna, such as Amussiopecten praesignis and Mimachlamys satoi are contained. The molluscan fauna of the Maja Formation is significant in understanding the origin of the Kakegawa Fauna, as the characteristic species of the Plio-Pleistocene Kakegawa Fauna already appeared in the Ryukyu Islands in the late Miocene. (author)

Sequence stratigraphy, seismic stratigraphy, and seismic structures of the lower intermediate confining unit and most of the Floridan aquifer system, Broward County, Florida

Science.gov (United States)

Cunningham, Kevin J.; Kluesner, Jared W.; Westcott, Richard L.; Robinson, Edward; Walker, Cameron; Khan, Shakira A.

2017-12-08

Deep well injection and disposal of treated wastewater into the highly transmissive saline Boulder Zone in the lower part of the Floridan aquifer system began in 1971. The zone of injection is a highly transmissive hydrogeologic unit, the Boulder Zone, in the lower part of the Floridan aquifer system. Since the 1990s, however, treated wastewater injection into the Boulder Zone in southeastern Florida has been detected at three treated wastewater injection utilities in the brackish upper part of the Floridan aquifer system designated for potential use as drinking water. At a time when usage of the Boulder Zone for treated wastewater disposal is increasing and the utilization of the upper part of the Floridan aquifer system for drinking water is intensifying, there is an urgency to understand the nature of cross-formational fluid flow and identify possible fluid pathways from the lower to upper zones of the Floridan aquifer system. To better understand the hydrogeologic controls on groundwater movement through the Floridan aquifer system in southeastern Florida, the U.S. Geological Survey and the Broward County Environmental Planning and Community Resilience Division conducted a 3.5-year cooperative study from July 2012 to December 2015. The study characterizes the sequence stratigraphy, seismic stratigraphy, and seismic structures of the lower part of the intermediate confining unit aquifer and most of the Floridan aquifer system.Data obtained to meet the study objective include 80 miles of high-resolution, two-dimensional (2D), seismic-reflection profiles acquired from canals in eastern Broward County. These profiles have been used to characterize the sequence stratigraphy, seismic stratigraphy, and seismic structures in a 425-square-mile study area. Horizon mapping of the seismic-reflection profiles and additional data collection from well logs and cores or cuttings from 44 wells were focused on construction of three-dimensional (3D) visualizations of eight

Stratigraphy and geologic history of Mercury

International Nuclear Information System (INIS)

Spudis, P.D.; Guest, J.E.

1988-01-01

The geologic evolution of Mercury based on the Mariner-10 mission data is discussed. As reconstructed through photogeological analysis of global geologic relations of rock-stratigraphic units, Mercury's geologic history is shown to involve intensive early impact bombardment and widespread resurfacing by volcanic lavas. Evidence is presented to indicate that this volcanic activity essentially ended as much as 3 Gyr ago, with most of the major geologic events being completed within the first 1 to 1.5 Gyr of Mercurian history

Stratigraphy and geologic history of Mercury

Science.gov (United States)

Spudis, Paul D.; Guest, John E.

1988-01-01

The geologic evolution of Mercury based on the Mariner-10 mission data is discussed. As reconstructed through photogeological analysis of global geologic relations of rock-stratigraphic units, Mercury's geologic history is shown to involve intensive early impact bombardment and widespread resurfacing by volcanic lavas. Evidence is presented to indicate that this volcanic activity essentially ended as much as 3 Gyr ago, with most of the major geologic events being completed within the first 1 to 1.5 Gyr of Mercurian history.

Late Quaternary stratigraphy and depositional history of the Long Island Sound basin

Science.gov (United States)

Lewis, Ralph S.; Stone, Janet R.

1991-01-01

The stratigraphy of Late Quaternary geologic units beneath Long Island Sound (LIS) is interpreted from 3,500 km of high-resolution, seismic-reflection profiles supplemented by vibracore data. Knowledge gained from onshore regional geologic studies and previous offshore investigations is also incorporated in these interpretations.

Geology of the 241-TY Tank Farm

International Nuclear Information System (INIS)

Price, W.H.; Fecht, K.R.

1976-04-01

A series of maps have been compiled to document the structure and stratigraphy of the sediments underlying the high-level radioactive waste storage tank farms located within the ERDA Hanford Reservation. The primary purpose of these maps is to provide basic geologic information to be utilized to evaluate the impact of suspected and confirmed tank leaks

Generalized geology of the 241-AW Tank Farm

International Nuclear Information System (INIS)

Last, G.V.; Marratt, M.C.

1978-08-01

A series of maps has been compiled to document the structure and stratigraphy of the sediments underlying the high-level radioactive waste storage tank farms located within the Hanford Reservation. Purpose is to provide basic geologic information to be utilized in support of the Long Term Management of Low Level Waste Program Data Base

Geocongress 84: 20. Geological congress of the Geological Society of South Africa. Abstracts: Pt. 1. General

International Nuclear Information System (INIS)

1984-01-01

Various aspects of the geology, geochemistry and geophysics of the geologic deposits in South Africa are dealt with. Uranium and thorium resources are included in this. There are also chapters on stratigraphy, petrology and petrochemistry

Geology of the 241-C Tank Farm

International Nuclear Information System (INIS)

Price, W.H.; Fecht, K.R.

1976-04-01

A series of maps have been compiled to document the structure and stratigraphy of the sediments underlying the high-level radioactive waste storage tank farms located within the Energy Research and Development Administration Hanford Reservation. The primary purpose of these maps is to provide basic geologic information to be utilized to evaluate the impact of suspected and confirmed tank leaks

Geology of the 241-SX Tank Farm

International Nuclear Information System (INIS)

Price, W.H.; Fecht, K.R.

1976-04-01

A series of maps have been compiled to document the structure and stratigraphy of the sediments underlying the high-level radioactive waste storage tank farms located within the Energy Research and Development Administration Hanford Reservation. The primary purpose of these maps is to provide basic geologic information to be utilized to evaluate the impact of suspected and confirmed tank leaks

Geology of the 241-S Tank Farm

International Nuclear Information System (INIS)

Price, W.H.; Fecht, K.R.

1976-04-01

A series of maps have been compiled to document the structure and stratigraphy of the sediments underlying the high-level radioactive waste storage tank farms located within the Energy Research and Development Administration Hanford Reservation. The primary purpose of these maps is to provide basic geologic information to be utilized to evaluate the impact of suspected and confirmed tank leaks

Geology of the 241-T Tank Farm

International Nuclear Information System (INIS)

Price, W.H.; Fecht, K.R.

1976-04-01

A series of maps have been compiled to document the structure and stratigraphy of the sediments underlying the high-level radioactive waste storage tank farms located within the Energy Research and Development Administration Hanford Reservation. The primary purpose of these maps is to provide basic geologic information to be utilized to evaluate the impact of suspected and confirmed tank leaks

Geology of the 241-TX Tank Farm

International Nuclear Information System (INIS)

Price, W.H.; Fecht, K.R.

1976-04-01

A series of maps have been compiled to document the structure and stratigraphy of the sediments underlying the high-level radioactive waste storage tank farms located within the Energy Research and Development Administration Hanford Reservation. The primary purpose of these maps is to provide basic geologic information to be utilized to evaluate the impact of suspected and confirmed tank leaks

Geology of the 241-U Tank Farm

International Nuclear Information System (INIS)

Price, W.H.; Fecht, K.R.

1976-04-01

A series of maps has been compiled to document the structure and stratigraphy of the sediments underlying the high-level radioactive waste storage tank farms located within the Energy Research and Development Administration Hanford Reservation. The primary purpose of these maps is to provide basic geologic information to be utilized to evaluate the impact of suspected and confirmed tank leaks

Volcano stratigraphy interpretation of Mamuju area based on Landsat-8 imagery analysis

International Nuclear Information System (INIS)

Frederikus Dian Indrastomo; I Gde Sukadana; Dhatu Kamajati; Asep Saepuloh; Agus Handoyo Harsolumakso

2015-01-01

Mamuju and its surrounding area are constructed mainly by volcanic rocks. Volcanoclastic sedimentary rocks and limestones are laid above the volcanic rocks. Volcanic activities create some unique morphologies such as craters, lava domes, and pyroclastic flow paths as their volcanic products. These products are identified from their circular features characters on Landsat-8 imagery. Geometric and atmospheric corrections had been done, a visual interpretation on Landsat-8 imagery was conducted to identify structure, geomorphology, and geological condition of the area. Regional geological structures show trend to southeast – northwest direction which is affects the formation of Adang volcano. Geomorphology of the area are classified into 16 geomorphology units based on their genetic aspects, i.e Sumare fault block ridge, Mamuju cuesta ridge, Adang eruption crater, Labuhan Ranau eruption crater, Sumare eruption crater, Ampalas volcanic cone, Adang lava dome, Labuhan Ranau intrusion hill, Adang pyroclastic flow ridge, Sumare pyroclastic flow ridge, Adang volcanic remnant hills, Malunda volcanic remnant hills, Talaya volcanic remnant hills, Tapalang karst hills, Mamuju alluvium plains, and Karampuang reef terrace plains. Based on the Landsat-8 imagery interpretation result and field confirmation, the geology of Mamuju area is divided into volcanic rocks and sedimentary rocks. There are two groups of volcanic rocks; Talaya complex and Mamuju complex. The Talaya complex consists of Mambi, Malunda, and Kalukku volcanic rocks with andesitic composition, while Mamuju complex consist of Botteng, Ahu, Tapalang, Adang, Ampalas, Sumare, and Labuhan Ranau volcanic rocks with andesite to leucitic basalt composition. The volcano stratigraphy of Mamuju area was constructed based on its structure, geomorphology and lithology distribution analysis. Volcano stratigraphy of Mamuju area is classified into Khuluk Talaya and Khuluk Mamuju. The Khuluk Talaya consists of Gumuk Mambi, Gumuk

A bibliography of planetary geology principal investigators and their associates, 1981 - 1982

Science.gov (United States)

Plescia, J. B. (Compiler)

1982-01-01

Over 800 publications submitted by researchers supported through NASA's Planetary Geology Program are cited and an author/editor index is provided. Entries are listed under the following subjects: (1) general interest topics; (2) solar system, comets, asteroids, and small bodies; (3) geologic mapping, geomorphology, and stratigraphy; (4) structure, tectonics, geologic and geophysical evolution; (5) impact craters: morphology, density, and geologic studies; (6) volcanism; (7) fluvial, mass wasting, and periglacial processes; (8) Eolian studies; (9) regolith, volatile, atmosphere, and climate; (10) remote sensing, radar, and photometry; and (11) cartography, photogrammetry, geodesy, and altimetry.

Uranium mineralization at Anomaly 2J, South Alligator Valley, Northern Territory, and its significance concerning regional structure and stratigraphy

International Nuclear Information System (INIS)

Foy, N.F.; Miezitis, Y.

1977-01-01

A weak airborne anomaly was examined in the field and the presence of uranium confirmed. Rotary-percussion drilling showed the presence of uranium but a subsequent programme of diamond and rotary-percussion drilling indicated that the concentration of uranium was uneconomic. Within the tuffs and volcanics of the prospect the uranium existed as uranyl phosphates within the oxidized zone. Geological mapping and the diamond drill core showed that the Stag Creek Volcanics are part of the Lower Proterozoic Masson Formation, probably with member status, rather than the expression of an Archaean basement ridge. This change in the interpretation of the fundamental structure of the Pine Creek Geosyncline has led to a re-examination of the stratigraphy and to suggestions which differ from the current concept. (author)

Generalized geology of the 241-SY Tank Farm

International Nuclear Information System (INIS)

Price, W.H.; Fecht, K.R.

1976-04-01

A series of maps has been compiled to document the structure and stratigraphy of the sediments underlying the high-level radioactive waste storage tank farms located within the Energy Research and Development Administration Hanford Reservation. The primary purpose of these maps is to provide the basic geologic information to be utilized to evaluate the impact of suspected and confirmed tank leaks

Evaluation of the structure and stratigraphy over Richton Dome, Mississippi

International Nuclear Information System (INIS)

Werner, M.L.

1986-05-01

The structure and stratigraphy over Richton Salt Dome, Mississippi, have been evaluated from 70 borings that were completed to various depths above the dome. Seven lithologic units have been identified and tentatively correlated with the regional Tertiary stratigraphy. Structure-contour and thickness maps of the units show the effects of dome growth from Eocene through early Pliocene time. Growth of the salt stock from late Oligocene through early Pliocene is estimated to have averaged 0.6 to 2.6 centimeters (0.2 to 1.1 inches) per 1000 years. No dome growth has occurred since the early Pliocene. The late Oligocene to early Pliocene strata over and adjacent to the dome reflect arching over the entire salt stock; some additional arching over individual centers may represent pre-Quaternary differential movement in the salt stock. The lithology and structure of the caprock at the Richton Salt Dome indicate that the caprock probably was completely formed by late Oligocene. In late Oligocene, the caprock was fractured by arching and altered by gypsum veining. Since late Oligocene, there are no indications of significant hydrologic connections through the caprock - that is, there are no indications of dissolution collapse or further anhydrite caprock accumulation. This structural and stratigraphic analysis provides insights on dome growth history, dome geometry, and neardome hydrostratigraphy that will aid in planning site characterization field activities, including an exploratory shaft, and in the conceptual design of a high-level waste (HLW) repository

Importance of geologic characterization of potential low-level radioactive waste disposal sites

Science.gov (United States)

Weibel, C.P.; Berg, R.C.

1991-01-01

Using the example of the Geff Alternative Site in Wayne County, Illinois, for the disposal of low-level radioactive waste, this paper demonstrates, from a policy and public opinion perspective, the importance of accurately determining site stratigraphy. Complete and accurate characterization of geologic materials and determination of site stratigraphy at potential low-level waste disposal sites provides the frame-work for subsequent hydrologic and geochemical investigations. Proper geologic characterization is critical to determine the long-term site stability and the extent of interactions of groundwater between the site and its surroundings. Failure to adequately characterize site stratigraphy can lead to the incorrect evaluation of the geology of a site, which in turn may result in a lack of public confidence. A potential problem of lack of public confidence was alleviated as a result of the resolution and proper definition of the Geff Alternative Site stratigraphy. The integrity of the investigation was not questioned and public perception was not compromised. ?? 1991 Springer-Verlag New York Inc.

Seismic stratigraphy, some examples from Indian Ocean, interpretation of reflection data in interactive mode

Digital Repository Service at National Institute of Oceanography (India)

Krishna, K.S.

the sedimentary layers on the basis of density-velocity contrasts. The surfaces may indicate unconformities or conformities. Eventually the method provides image of the sedimentary strata with internal surfaces and basaltic basement and occasionally its... underneath along a profile. Earth scientists will interpret these images in terms of stratigraphy. In simple terminology the seismic stratigraphy can be defined as a viewing of seismic reflection data with a geological approach. Total...

Fundamentals of Structural Geology

Science.gov (United States)

Pollard, David D.; Fletcher, Raymond C.

2005-09-01

Fundamentals of Structural Geology provides a new framework for the investigation of geological structures by integrating field mapping and mechanical analysis. Assuming a basic knowledge of physical geology, introductory calculus and physics, it emphasizes the observational data, modern mapping technology, principles of continuum mechanics, and the mathematical and computational skills, necessary to quantitatively map, describe, model, and explain deformation in Earth's lithosphere. By starting from the fundamental conservation laws of mass and momentum, the constitutive laws of material behavior, and the kinematic relationships for strain and rate of deformation, the authors demonstrate the relevance of solid and fluid mechanics to structural geology. This book offers a modern quantitative approach to structural geology for advanced students and researchers in structural geology and tectonics. It is supported by a website hosting images from the book, additional colour images, student exercises and MATLAB scripts. Solutions to the exercises are available to instructors. The book integrates field mapping using modern technology with the analysis of structures based on a complete mechanics MATLAB is used to visualize physical fields and analytical results and MATLAB scripts can be downloaded from the website to recreate textbook graphics and enable students to explore their choice of parameters and boundary conditions The supplementary website hosts color images of outcrop photographs used in the text, supplementary color images, and images of textbook figures for classroom presentations The textbook website also includes student exercises designed to instill the fundamental relationships, and to encourage the visualization of the evolution of geological structures; solutions are available to instructors

Introduction to uranium geology of the Kaycee area in Johnson county, Wyoming

International Nuclear Information System (INIS)

Li Wuwei

2004-01-01

The geology of the Kaycee uranium deposit is introduced in three aspects: regional setting, stratigraphy and structure. At the same time, uranium and vanadium mineralization of significant economic potential have been reported in the sandstones and conglomerates from Paleocene to Eocene period in the eastern and northeastern part of Kaycee, Wyoming. (authors)

Sequence stratigraphy as a scientific enterprise: the evolution and persistence of conflicting paradigms

Science.gov (United States)

Miall, Andrew D.; Miall, Charlene E.

2001-08-01

In the 1970s, seismic stratigraphy represented a new paradigm in geological thought. The development of new techniques for analyzing seismic-reflection data constituted a "crisis," as conceptualized by T.S. Kuhn, and stimulated a revolution in stratigraphy. We analyze here a specific subset of the new ideas, that pertaining to the concept of global-eustasy and the global cycle chart published by Vail et al. [Vail, P.R., Mitchum, R.M., Jr., Todd, R.G., Widmier, J.M., Thompson, S., III, Sangree, J.B., Bubb, J.N., Hatlelid, W.G., 1977. Seismic stratigraphy and global changes of sea-level. In: Payton, C.E. (Ed.), Seismic Stratigraphy—Applications to Hydrocarbon Exploration, Am. Assoc. Pet. Geol. Mem. 26, pp. 49-212.] The global-eustasy model posed two challenges to the "normal science" of stratigraphy then underway: (1) that sequence stratigraphy, as exemplified by the global cycle chart, constitutes a superior standard of geologic time to that assembled from conventional chronostratigraphic evidence, and (2) that stratigraphic processes are dominated by the effects of eustasy, to the exclusion of other allogenic mechanisms, including tectonism. While many stratigraphers now doubt the universal validity of the model of global-eustasy, what we term the global-eustasy paradigm, a group of sequence researchers led by Vail still adheres to it, and the two conceptual approaches have evolved into two conflicting paradigms. Those who assert that there are multiple processes generating stratigraphic sequences (possibly including eustatic processes) are adherents of what we term the complexity paradigm. Followers of this paradigm argue that tests of the global cycle chart amount to little more than circular reasoning. A new body of work documenting the European sequence record was published in 1998 by de Graciansky et al. These workers largely follow the global-eustasy paradigm. Citation and textual analysis of this work indicates that they have not responded to any of the

A Geostatistical Toolset for Reconstructing Louisiana's Coastal Stratigraphy using Subsurface Boring and Cone Penetrometer Test Data

Science.gov (United States)

Li, A.; Tsai, F. T. C.; Jafari, N.; Chen, Q. J.; Bentley, S. J.

2017-12-01

A vast area of river deltaic wetlands stretches across southern Louisiana coast. The wetlands are suffering from a high rate of land loss, which increasingly threats coastal community and energy infrastructure. A regional stratigraphic framework of the delta plain is now imperative to answer scientific questions (such as how the delta plain grows and decays?) and to provide information to coastal protection and restoration projects (such as marsh creation and construction of levees and floodwalls). Through years, subsurface investigations in Louisiana have been conducted by state and federal agencies (Louisiana Department of Natural Resources, United States Geological Survey, United States Army Corps of Engineers, etc.), research institutes (Louisiana Geological Survey, LSU Coastal Studies Institute, etc.), engineering firms, and oil-gas companies. This has resulted in the availability of various types of data, including geological, geotechnical, and geophysical data. However, it is challenging to integrate different types of data and construct three-dimensional stratigraphy models in regional scale. In this study, a set of geostatistical methods were used to tackle this problem. An ordinary kriging method was used to regionalize continuous data, such as grain size, water content, liquid limit, plasticity index, and cone penetrometer tests (CPTs). Indicator kriging and multiple indicator kriging methods were used to regionalize categorized data, such as soil classification. A compositional kriging method was used to regionalize compositional data, such as soil composition (fractions of sand, silt and clay). Stratigraphy models were constructed for three cases in the coastal zone: (1) Inner Harbor Navigation Canal (IHNC) area: soil classification and soil behavior type (SBT) stratigraphies were constructed using ordinary kriging; (2) Middle Barataria Bay area: a soil classification stratigraphy was constructed using multiple indicator kriging; (3) Lower Barataria

Analysis on metallogenetic geological and physicochemical conditions in uranium deposit No.138

International Nuclear Information System (INIS)

Tang Qitao

1996-01-01

The uranium deposit No.138 is of Mesozoic volcano-sedimentary transformation type. This paper discusses such geological conditions as source of uranium, stratigraphy and lithology, lithofacies and paleogeography, paleoclimate, structure and reworking-regeneration, and such physicochemical conditions as uranium adsorbent and reductant, effective porosity, chemical compositions, pH and Eh of rocks in the deposit

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.

Stratigraphy of the Martian northern plains

Science.gov (United States)

Tanaka, K. L.

1993-01-01

The northern plains of Mars are roughly defined as the large continuous region of lowlands that lies below Martian datum, plus higher areas within the region that were built up by volcanism, sedimentation, tectonism, and impacts. These northern lowlands span about 50 x 10(exp 6) km(sup 2) or 35 percent of the planet's surface. The age and origin of the lowlands continue to be debated by proponents of impact and tectonic explanations. Geologic mapping and topical studies indicate that volcanic, fluvial, and eolian deposition have played major roles in the infilling of this vast depression. Periglacial, glacial, fluvial, eolian, tectonic, and impact processes have locally modified the surface. Because of the northern plains' complex history of sedimentation and modification, much of their stratigraphy was obscured. Thus the stratigraphy developed is necessarily vague and provisional: it is based on various clues from within the lowlands as well as from highland areas within and bordering the plains. The results are summarized.

3. South American symposium on isotope geology. Extended abstracts

International Nuclear Information System (INIS)

2001-10-01

This publication include papers in the fields on Methodology, thermochronology, and geochronology; Evolution of cratonic South America; Magmatic processes; Environmental geology, hydrogeology, isotopic stratigraphy and paleoclimatology; Economic Geology and Evolution of the Andean margin of South America

Genetic stratigraphy of Coniacian deltaic deposits of the northwestern part of the Bohemian Cretaceous Basin

Czech Academy of Sciences Publication Activity Database

Nádaskay, R.; Uličný, David

2014-01-01

Roč. 165, č. 4 (2014), s. 547-575 ISSN 1860-1804 Institutional support: RVO:67985530 Keywords : genetic stratigraphy * well log * Bohemian Cretaceous Basin Subject RIV: DB - Geology ; Mineralogy Impact factor: 0.569, year: 2014

Analysis of geological condition of uranium mineralization in the Xiangshan northern uranium orefield in central region of Jiangxi Province

International Nuclear Information System (INIS)

Zhou Yulong; Liu Yunlang; Gao Yan

2013-01-01

According to the basic conditions of 'source, guide, transportation, storage' for uranium mineralization in strata and different types of geological structure, departure from the condition, the coupling effect of stratigraphy, lithology and structure are studied in the process of uranium mineralization in northern Xiangshan volcanic basin. Studies show that the northern ore field are of good metallogenic geological conditions and the uranium rich ancient land mass and uranium rich magma generated by the melting of deep metamorphic rocks. The main geologic events are volcanic eruptions, accompanied by repeated subvolcanic magma intrusion and strong faults and nappe tectonics which result in volcanic collapse and volcanic ring structures. These ore-forming geological condition control the structural frame for the formation of main uranium deposit type-subvolcanic rocks in northern Xiangshan ore field. (authors)

Explicative memory of the geologic map of Uruguay. Esc. 1.500.000

International Nuclear Information System (INIS)

Preciozzi Porta, F.; Spoturno, J.; Rossi, P.; Heinzen, W.

1985-01-01

The Geological Map of Uruguay Esc. 1.500.000 is part of the Geological Map Programme developed by the Institute Geologic during the years 1977 - 1980. Its memory describe the geography, the lit ho stratigraphy and the crystalline area in the soil of Uruguay.

How to Make Eccentricity Cycles in Stratigraphy: the Role of Compaction

Science.gov (United States)

Liu, W.; Hinnov, L.; Wu, H.; Pas, D.

2017-12-01

Milankovitch cycles from astronomically driven climate variations have been demonstrated as preserved in cyclostratigraphy throughout geologic time. These stratigraphic cycles have been identified in many types of proxies, e.g., gamma ray, magnetic susceptibility, oxygen isotopes, carbonate content, grayscale, etc. However, the commonly prominent spectral power of orbital eccentricity cycles in stratigraphy is paradoxical to insolation, which is dominated by precession index power. How is the spectral power transferred from precession to eccentricity in stratigraphy? Nonlinear sedimentation and bioturbation have long been identified as players in this transference. Here, we propose that in the absence of bioturbation differential compaction can generate the transference. Using insolation time series, we trace the steps by which insolation is transformed into stratigraphy, and how differential compaction of lithology acts to transfer spectral power from precession to eccentricity. Differential compaction is applied to unique values of insolation, which is assumed to control the type of deposited sediment. High compaction is applied to muds, and progressively lower compaction is applied to silts and sands, or carbonate. Linear differential compaction promotes eccentricity spectral power, but nonlinear differential compaction elevates eccentricity spectral power to dominance and precession spectral power to near collapse as is often observed in real stratigraphy. Keywords: differential compaction, cyclostratigraphy, insolation, eccentricity

Thermoluminescence studies in geology

International Nuclear Information System (INIS)

Sankaran, A.V.; Sunta, C.M.; Nambi, K.S.V.; Bapat, V.N.

1980-01-01

Even though the phenomenon of thermoluminescence is well studied, particularly over last 3 decades, its potentialities in the field of geology have not been adequately evaluated. In this report several useful applications of TL in mineralogy, petrogenesis, stratigraphy, tectonics, ore-prospecting and other branches have been identified with particular emphasis to the Indian scene. Important areas in the country that may provide the basic material for such studies are indicated at the end along with brief geological or mineralogical accounts. (auth.)

Origin, sequence stratigraphy and depositional environment of an Upper Ordovician (Hirnantian) deglacial black shale, Jordan-Discussion

Czech Academy of Sciences Publication Activity Database

Lüning, S.; Loydell, D. K.; Štorch, Petr; Shahin, Y.; Craig, J.

2006-01-01

Roč. 230, 3-4 (2006), s. 352-355 ISSN 0031-0182 Institutional research plan: CEZ:AV0Z30130516 Keywords : Silurian * black shale * sequence stratigraphy Subject RIV: DB - Geology ; Mineralogy Impact factor: 1.822, year: 2006

Admissible thermal loading in geological formations. Consequences on radioactive waste disposal methods

International Nuclear Information System (INIS)

1982-01-01

The thermal loading in salt formation is studied for the disposal of high-level radioactive waste embedded in glass. Temperature effect on glass leaching, stability of gel layer on glass surface, quantity of leaching solution available in the borehole and corrosion resistance of materials used for containers are examined. The geological storage medium must satisfy particularly complex requirements: stratigraphy, brine migration, permeability, fissuring, mechanical strength, creep, thermal expansion, cavity structure ..

Geology and coal potential of Somaliland

Energy Technology Data Exchange (ETDEWEB)

M.Y. Ali [Petroleum Institute, Abu Dhabi (United Arab Emirates)

2009-07-01

Geological field mapping along with available geological and drilling data suggest that Somaliland (Northwestern Somalia) has favourable stratigraphy and structure for coal deposits. Lignitic to sub-bituminous coal deposits with ages from Jurassic to Oligocene-Miocene occur in various locations across the country including Hed-Hed valley south of Onkhor, Guveneh hills north of Las Dureh and Daban Basin southeast of Berbera. However, the coal occurrence at Hed-Hed has both the greatest thickness and highest quality. These deposits have the potential to provide an important alternative fuel resource which could alleviate the growing shortage of traditional fuels and assist in reducing the country's dependence on imported energy. However, further investigation, including drilling and laboratory analyses, still needs to be carried out, particularly on the Upper Cretaceous coal seams to evaluate the quality and resource potential of the deposits.

Geologic Framework Model Analysis Model Report

Energy Technology Data Exchange (ETDEWEB)

R. Clayton

2000-12-19

The purpose of this report is to document the Geologic Framework Model (GFM), Version 3.1 (GFM3.1) with regard to data input, modeling methods, assumptions, uncertainties, limitations, and validation of the model results, qualification status of the model, and the differences between Version 3.1 and previous versions. The GFM represents a three-dimensional interpretation of the stratigraphy and structural features of the location of the potential Yucca Mountain radioactive waste repository. The GFM encompasses an area of 65 square miles (170 square kilometers) and a volume of 185 cubic miles (771 cubic kilometers). The boundaries of the GFM were chosen to encompass the most widely distributed set of exploratory boreholes (the Water Table or WT series) and to provide a geologic framework over the area of interest for hydrologic flow and radionuclide transport modeling through the unsaturated zone (UZ). The depth of the model is constrained by the inferred depth of the Tertiary-Paleozoic unconformity. The GFM was constructed from geologic map and borehole data. Additional information from measured stratigraphy sections, gravity profiles, and seismic profiles was also considered. This interim change notice (ICN) was prepared in accordance with the Technical Work Plan for the Integrated Site Model Process Model Report Revision 01 (CRWMS M&O 2000). The constraints, caveats, and limitations associated with this model are discussed in the appropriate text sections that follow. The GFM is one component of the Integrated Site Model (ISM) (Figure l), which has been developed to provide a consistent volumetric portrayal of the rock layers, rock properties, and mineralogy of the Yucca Mountain site. The ISM consists of three components: (1) Geologic Framework Model (GFM); (2) Rock Properties Model (RPM); and (3) Mineralogic Model (MM). The ISM merges the detailed project stratigraphy into model stratigraphic units that are most useful for the primary downstream models and the

Geologic Framework Model Analysis Model Report

International Nuclear Information System (INIS)

Clayton, R.

2000-01-01

The purpose of this report is to document the Geologic Framework Model (GFM), Version 3.1 (GFM3.1) with regard to data input, modeling methods, assumptions, uncertainties, limitations, and validation of the model results, qualification status of the model, and the differences between Version 3.1 and previous versions. The GFM represents a three-dimensional interpretation of the stratigraphy and structural features of the location of the potential Yucca Mountain radioactive waste repository. The GFM encompasses an area of 65 square miles (170 square kilometers) and a volume of 185 cubic miles (771 cubic kilometers). The boundaries of the GFM were chosen to encompass the most widely distributed set of exploratory boreholes (the Water Table or WT series) and to provide a geologic framework over the area of interest for hydrologic flow and radionuclide transport modeling through the unsaturated zone (UZ). The depth of the model is constrained by the inferred depth of the Tertiary-Paleozoic unconformity. The GFM was constructed from geologic map and borehole data. Additional information from measured stratigraphy sections, gravity profiles, and seismic profiles was also considered. This interim change notice (ICN) was prepared in accordance with the Technical Work Plan for the Integrated Site Model Process Model Report Revision 01 (CRWMS M and O 2000). The constraints, caveats, and limitations associated with this model are discussed in the appropriate text sections that follow. The GFM is one component of the Integrated Site Model (ISM) (Figure l), which has been developed to provide a consistent volumetric portrayal of the rock layers, rock properties, and mineralogy of the Yucca Mountain site. The ISM consists of three components: (1) Geologic Framework Model (GFM); (2) Rock Properties Model (RPM); and (3) Mineralogic Model (MM). The ISM merges the detailed project stratigraphy into model stratigraphic units that are most useful for the primary downstream models and

Review of the upper Cenozoic stratigraphy overlying the Columbia River Basalt Group in western Idaho

International Nuclear Information System (INIS)

Strowd, W.B.

1980-12-01

This report is a synthesis of information currently available on the rocks that stratigraphically overlie the Columbia River Basalt Group in Idaho. The primary objective is to furnish a brief but comprehensive review of the literature available on upper Cenozoic rocks in western Idaho and to discuss their general stratigraphic relationships. This study also reviews the derivation of the present stratigraphy and notes weaknesses in our present understanding of the geology and the stratigraphy. This report was prepared in support of a study to evaluate the feasibility of nuclear waste storage in the Columbia River Basalt Group of the Pasco Basin, Washington

Linking descriptive geology and quantitative machine learning through an ontology of lithological concepts

Science.gov (United States)

Klump, J. F.; Huber, R.; Robertson, J.; Cox, S. J. D.; Woodcock, R.

2014-12-01

Despite the recent explosion of quantitative geological data, geology remains a fundamentally qualitative science. Numerical data only constitute a certain part of data collection in the geosciences. In many cases, geological observations are compiled as text into reports and annotations on drill cores, thin sections or drawings of outcrops. The observations are classified into concepts such as lithology, stratigraphy, geological structure, etc. These descriptions are semantically rich and are generally supported by more quantitative observations using geochemical analyses, XRD, hyperspectral scanning, etc, but the goal is geological semantics. In practice it has been difficult to bring the different observations together due to differing perception or granularity of classification in human observation, or the partial observation of only some characteristics using quantitative sensors. In the past years many geological classification schemas have been transferred into ontologies and vocabularies, formalized using RDF and OWL, and published through SPARQL endpoints. Several lithological ontologies were compiled by stratigraphy.net and published through a SPARQL endpoint. This work is complemented by the development of a Python API to integrate this vocabulary into Python-based text mining applications. The applications for the lithological vocabulary and Python API are automated semantic tagging of geochemical data and descriptions of drill cores, machine learning of geochemical compositions that are diagnostic for lithological classifications, and text mining for lithological concepts in reports and geological literature. This combination of applications can be used to identify anomalies in databases, where composition and lithological classification do not match. It can also be used to identify lithological concepts in the literature and infer quantitative values. The resulting semantic tagging opens new possibilities for linking these diverse sources of data.

A bibliography of planetary geology principal investigators and their associates, 1982 - 1983

Science.gov (United States)

Plescia, J. B.

1984-01-01

This bibliography cites recent publications by principal investigators and their associates, supported through NASA's Office of Space Science and Applications, Earth and Planetary Exploration Division, Planetary Geology Program. It serves as a companion piece to NASA TM-85127, ""Reports of Planetary Programs, 1982". Entries are listed under the following subject areas: solar system, comets, asteroids, meteorites and small bodies; geologic mapping, geomorphology, and stratigraphy; structure, tectonics, and planetary and satellite evolutions; impact craters; volcanism; fluvial, mass wasting, glacial and preglacial studies; Eolian and Arid climate studies; regolith, volatiles, atmosphere, and climate, radar; remote sensing and photometric studies; and cartography, photogrammetry, geodesy, and altimetry. An author index is provided.

Stratigraphy of the south polar region of Ganymede

Science.gov (United States)

Dehon, R. A.

1987-01-01

A preliminary assessment is made of the stratigraphy and geology in the south polar region of the Jovian satellite, Ganymede. Geologic mapping is based on inspection of Voyager images and compilation on an airbrush base map at a scale of 1:5M. Illumination and resolution vary greatly in the region. Approximately half of the quadripole is beyond the terminator. Low angle illumination over a large part of the area precludes distinction of some units by albedo characteristics. Several types of grooved terrain and groove related terrain occur in the southern polar region. Grooves typically occur in straight to curvilinear sets or lanes. Bright lanes and grooved lanes intersect at high angles outlining polygons of dark cratered terrain. Groove sets exhibit a range of ages as shown by superposition or truncation and by crater superposition ages.

Stratigraphy and correlation of the Manitou Falls formation, the Athabasca Group

International Nuclear Information System (INIS)

Iida, Yoshimasa; Ikeda, Koki; Tsuruta, Tadahiko; Yamada, Yasuo; Ito, Hiroaki; Goto, Junichi

1996-01-01

Manitou Falls formation is the thick strata of Proterozoic era that spread widely in the uranium deposit zone in Northern Saskatchewan, Canada (Athabasca basin). In order to study in detail underground geological structure by trial boring, it is necessary to distinguish and compare strata by dividing them into the units as small as possible. The Manitou Falls formation is composed of only sandstone and conglomerate, and it does not have simply identified, continuous strata like tuff and coal layers. In the Christie Lake B district located in Eastern Athabasca basin, the division of strata was carried out by utilizing the data of the changes in the volume ratio of conglomerate layer and maximum pebble size and natural radioactivity logging and based on the careful comparison among trial bores. As the result, this formation was divided into the units of 9 strata. As one of the methods of identifying each unit, the comparison of the power spectra of natural radioactivity logging data was attempted. By this means, it was found that the features in the periodicity of stratum accumulation are useful for identifying strata. The outline of the Manitou Falls formation, the location of the investigated district, the basic data for stratigraphy division, the stratigraphy division in Christie Lake B district and the results are reported. (K.I.)

Area geological characterization report for the Palo Duro and Dalhart Basins, Texas

International Nuclear Information System (INIS)

1983-07-01

The present state of knowledge of the geology, hydrogeology, and seismology of the Palo Duro and Dalhart basins is summarized as a basis for future siting studies for a high-level nuclear waste repository. Large portions of the Texas Panhandle, and especially the Palo Duro basin, have stable geologic conditions and a favorable evaporite stratigraphy that warrant further study. Five salt-bearing formations containing thick salt units are present within the basin. Salt beds appear to be persistent over wide areas, relatively flat lying and structurally undisturbed. Available hydrogeologic data suggest that favorable conditions for waste isolation are widespread. The level and rate of seismic activity are low throughout the Texas Panhandle. 335 references, 83 figures, 17 tables

Stratigraphy and Observations of Nepthys Mons Quadrangle (V54), Venus

Science.gov (United States)

Bridges, N. T.

2001-01-01

Initial mapping has begun in Venus' Nepthys Mons Quadrangle (V54, 300-330 deg. E, 25-50 deg. S). Major research areas addressed are how the styles of volcanism and tectonism have changed with time, the evolution of shield volcanoes, the evolution of coronae, the characteristics of plains volcanism, and what these observations tell us about the general geologic history of Venus. Reported here is a preliminary general stratigraphy and several intriguing findings. Additional information is contained in the original extended abstract.

Stratigraphy of the Harwell boreholes

International Nuclear Information System (INIS)

Gallois, R.W.; Worssam, B.C.

1983-12-01

Seven boreholes, five of them partially cored, were drilled at the Atomic Energy Research Establishment at Harwell as part of a general investigation to assess the feasibility of storing low- and intermediate-level radioactive waste in underground cavities. Two of the deeper boreholes were almost wholly cored to provide samples for hydrogeological, hydrochemical, mineralogical, geochemical, geotechnical, sedimentological and stratigraphical studies to enable variations in lithology and rock properties to be assessed, both vertically and laterally, and related to their regional geological setting. This report describes the lithologies, main faunal elements and stratigraphy of the Cretaceous, Jurassic, Triassic and Carboniferous sequences proved in the boreholes. More detailed stratigraphical accounts of the late Jurassic and Cretaceous sequences will be prepared when current studies of the faunal assemblages are complete. (author)

Sculpting Mountains: Interactive Terrain Modeling Based on Subsurface Geology.

Science.gov (United States)

Cordonnier, Guillaume; Cani, Marie-Paule; Benes, Bedrich; Braun, Jean; Galin, Eric

2018-05-01

Most mountain ranges are formed by the compression and folding of colliding tectonic plates. Subduction of one plate causes large-scale asymmetry while their layered composition (or stratigraphy) explains the multi-scale folded strata observed on real terrains. We introduce a novel interactive modeling technique to generate visually plausible, large scale terrains that capture these phenomena. Our method draws on both geological knowledge for consistency and on sculpting systems for user interaction. The user is provided hands-on control on the shape and motion of tectonic plates, represented using a new geologically-inspired model for the Earth crust. The model captures their volume preserving and complex folding behaviors under collision, causing mountains to grow. It generates a volumetric uplift map representing the growth rate of subsurface layers. Erosion and uplift movement are jointly simulated to generate the terrain. The stratigraphy allows us to render folded strata on eroded cliffs. We validated the usability of our sculpting interface through a user study, and compare the visual consistency of the earth crust model with geological simulation results and real terrains.

Three-dimensional model of reference thermal/mechanical and hydrological stratigraphy at Yucca Mountain, southern Nevada

International Nuclear Information System (INIS)

Ortiz, T.S.; Williams, R.L.; Nimick, F.B.; Whittet, B.C.; South, D.L.

1985-10-01

The Nevada Nuclear Waste Storage Investigations (NNWSI) project is currently examining the feasibility of constructing a nuclear waste repository in the tuffs beneath Yucca Mountain. A three-dimensional model of the thermal/mechanical and hydrological reference stratigraphy at Yucca Mountain has been developed for use in performance assessment and repository design studies involving material properties data. The reference stratigraphy defines units with distinct thermal, physical, mechanical, and hydrological properties. The model is a collection of surface representations, each surface representing the base of a particular unit. The reliability of the model was evaluated by comparing the generated surfaces, existing geologic maps and cross sections, drill hole data, and geologic interpolation. Interpolation of surfaces between drill holes by the model closely matches the existing information. The top of a zone containing prevalent zeolite is defined and superimposed on the reference stratigraphy. Interpretation of the geometric relations between the zeolitic and thermal/mechanical and hydrological surfaces indicates that the zeolitic zone was established before the major portion of local fault displacement took place; however, faulting and zeolitization may have been partly concurrent. The thickness of the proposed repository host rock, the devitrified, relatively lithophysal-poor, moderately to densely welded portion of the Topopah Spring Member of the Paintbrush Tuff, was evaluated and varies from 400 to 800 ft in the repository area. The distance from the repository to groundwater level was estimated to vary from 700 to 1400 ft. 13 figs., 1 tab

Stratigraphy of the Roraima Supergroup along the Brazil-Guyana border in the Guiana shield, Northern Amazonian Craton - results of the Brazil-Guyana Geology and Geodiversity Mapping Project

Directory of Open Access Journals (Sweden)

Nelson Joaquim Reis

Full Text Available ABSTRACT: The Geological and Geodiversity Mapping binational program along the Brazil-Guyana border zone allowed reviewing and integrating the stratigraphy and nomenclature of the Roraima Supergroup along the Pakaraima Sedimentary Block present in northeastern Brazil and western Guyana. The area mapped corresponds to a buffer zone of approximately 25 km in width on both sides of the border, of a region extending along the Maú-Ireng River between Mount Roraima (the triple-border region and Mutum Village in Brazil and Monkey Mountain in Guyana. The south border of the Roraima basin is overlain exclusively by effusive and volcaniclastic rocks of the Surumu Group of Brazil and its correlated equivalent the Burro-Burro Group of Guyana.

Stratigraphy of the late Cenozoic sediments beneath the 216-A Crib Facilities

International Nuclear Information System (INIS)

Fecht, K.R.; Last, G.V.; Marratt, M.C.

1979-02-01

The stratigraphy of the late Cenozoic sediments beneath the 216-A Crib Facilities is presented as lithofacies cross sections and is based on textural variations of the sedimentary sequence lying above the basalt bedrock. The primary source of data in this study is geologic information obtained from well drilling operations and geophysical logging. Stratigraphic interpretations are based primarily on textural analysis and visual examination of sediment samples and supplemented by drillers logs and geophysical logs

Lawrence Livermore Laboratory Nuclear Test Effects and Geologic Data Bank

International Nuclear Information System (INIS)

Howard, N.W.

1976-01-01

Data on the geology of the USERDA Nevada Test Site have been collected for the purpose of evaluating the possibility of release of radioactivity at proposed underground nuclear test sites. These data, including both the rock physical properties and the geologic structure and stratigraphy of a large number of drill-hole sites, are stored in the Lawrence Livermore Laboratory Earth Sciences Division Nuclear Test Effects and Geologic Data Bank. Retrieval programs can quickly provide a geological and geophysical comparison of a particular site with other sites where radioactivity was successfully contained. The data can be automatically sorted, compared, and averaged, and information listed according to site location, drill-hole construction, rock units, depth to key horizons and to the water table, and distance to faults. These programs also make possible ordered listings of geophysical properties (interval bulk density, overburden density, interval velocity, velocity to the surface, grain density, water content, carbonate content, porosity, and saturation of the rocks). The characteristics and capabilities of the data bank are discussed

Study on geologic structure of hydrogenic deposits

International Nuclear Information System (INIS)

1985-01-01

The problem of studying geologic structure of hydrogenic uranium deposits developed by underground leaching (UL), is elucidated. Geologic maps of the surface are used to characterize engineering and geologic conditions. Main geologoic papers are maps drawn up according to boring data. For total geologic characteristic of the deposit 3 types of maps are usually drawn up: structural maps of isohypses or isodepths, lithologic-facies maps on the horizon and rhythm, and maps of epigenetic alterations (geochemmcal). Besides maps systems of sections are drawn up. Problems of studying lithologic-facies and geohemical peculiarities of deposits, epigenotic alterations, substance composition of ores and enclosing rocks, documentation and core sampting, are considered in details

Mechanics of wind ripple stratigraphy.

Science.gov (United States)

Forrest, S B; Haff, P K

1992-03-06

Stratigraphic patterns preserved under translating surface undulations or ripples in a depositional eolian environment are computed on a grain by grain basis using physically based cellular automata models. The spontaneous appearance, growth, and motion of the simulated ripples correspond in many respects to the behavior of natural ripples. The simulations show that climbing strata can be produced by impact alone; direct action of fluid shear is unnecessary. The model provides a means for evaluating the connection between mechanical processes occurring in the paleoenvironment during deposition and the resulting stratigraphy preserved in the geologic column: vertical compression of small laminae above a planar surface indicates nascent ripple growth; supercritical laminae are associated with unusually intense deposition episodes; and a plane erosion surface separating sets of well-developed laminae is consistent with continued migration of mature ripples during a hiatus in deposition.

Geology of the Integrated Disposal Facility Trench

International Nuclear Information System (INIS)

Reidel, Steve P.; Fecht, Karl R.

2005-01-01

This report describes the geology of the integrated Disposal Facility (IDF) Trench. The stratigraphy consists of some of the youngest sediments of the Missoula floods (younger than 770 ka). The lithology is dominated sands with minor silts and gravels that are largely unconsolidated. The stratigraphy can be subdivided into five geologic units that can be mapped throughout the trench. Four of the units were deposited by the Missoula floods and the youngest consists of windblown sand and silt. The sediment has little moisture and is consistent with that observed in the characterization boreholes. The sedimentary layers are flat lying and there are no faults or folds present. Two clastic dikes were encountered, one along the west wall and one that can be traced from the north to the southwall. The north-south clastic dike nearly bifurcates the trench but the west wall clastic dike can not be traced very far east into the trench. The classic dikes consist mainly of sand with clay-lined walls. The sediment in the dikes is compacted to partly cemented and are more resistant than the layered sediments

Integrated stratigraphy of the Jurassic-Cretaceous sequences of the Kurovice Quarry, Outer Western Carpathians: correlations and tectonic implications

Czech Academy of Sciences Publication Activity Database

Pruner, Petr; Schnabl, Petr; Čížková, Kristýna; Elbra, Tiiu; Kdýr, Šimon; Svobodová, Andrea; Reháková, D.

2017-01-01

Roč. 120 (2017), s. 216-216 ISSN 1017-8880. [International Symposium on the Cretaceous /10./. 21.08.2017-26.08.2017, Vienna] R&D Projects: GA ČR(CZ) GA16-09979S Institutional support: RVO:67985831 Keywords : stratigraphy * Jurassic-Cretaceous sequences * Western Carpathians Subject RIV: DB - Geology ; Mineralogy

Bibliography of geologic studies: Columbia Plateau (Columbia River Basalt) and adjacent areas in Idaho

International Nuclear Information System (INIS)

Strowd, W.

1978-11-01

The objective of this compilation is to present a comprehensive listing of published, unpublished, and open-file references pertaining to the geology of the Columbia Plateau and adjacent areas in the State of Idaho. The bibliography was compiled in support of Rockwell's Basalt Waste Isolation Program that is evaluating the feasibility of nuclear waste storage in the Columbia River Basalt Group. The emphasis is on stratigraphy, structural geology, seismicity, and tectonics, although the nature of Columbia River Basalt distribution in Idaho has necessitated the inclusion of a sizeable collection of references on geology marginal to the Columbia Plateau and associated mineral resources. The bibliography is divided into two major sections, the alphabetical listing of all references and the subject index. The subject index is divided into 19 categories to facilitate locating a specific reference in the user's field of interest

Sequence stratigraphy and uranium metallogenic characteristics in Xinminpu group, lower cretaceous, in Gongpoquan basin

International Nuclear Information System (INIS)

Gong Binli; Wang Jingping

2006-01-01

Characteristics of sequence stratigraphy, the distribution and the geologic time of sequence, boundary features and internal composition, the sedimentary facies, as well as the characteristics of interlayer oxidation zone and U-mineralization are expounded. It is suggested that the Gongpoquan area is of certain prospect for U-prospecting, and uranium metallogenic conditions are not favorable in the Beiluotuoquan area, and the Nalinsuhuai area has no prospect either. (authors)

Geologic setting of diverse volcanic materials in northern Elysium Planitia, Mars

International Nuclear Information System (INIS)

Mouginis-Mark, P.J.

1990-01-01

Geologic mapping of high-resolution (30-50 m/pixel) Viking Orbiter images of northern Elysium Planitia has identified seven sites where current problems in martian volcanology, chronology, and stratigraphy can be resolved. These sites, which are discussed in the context of a potential Mars rover/sample return mission, would permit the following investigations: (1) the dating of Lower Amazonian lava flows from Elysium Mons (thereby providing absolute calibration for global crater size/frequency relative chronologies), (2) the petrologic investigation of long run-out lava flows, (3) the geologic interpretation of materials that may either be lava flows or lahar deposits, (4) the analysis of materials believed to be ash deposits produced by explosive eruptions of Hecates Tholus, and (5) the investigation of the stratigraphy of fractured terrain along the boundary between northern Elysium Planitia and southern Utopia Planitia. 63 refs

Preliminary geology of eastern Umtanum Ridge, South-Central Washington

Energy Technology Data Exchange (ETDEWEB)

Goff, F.E.

1981-01-01

The basalt stratigraphy and geologic structures of eastern Umtanum Ridge have been mapped and studied in detail to help assess the feasibility of nuclear waste terminal storage on the Hanford Site in southeastern Washington State. Eastern Umtanum Ridge is an asymmetric east-west-trending anticline of Columbia River basalt that plunges 5 degrees eastward into the Pasco Basin. Geologic mapping and determination of natural remanent magnetic polarity and chemical composition reveal that flows of the Pomona and Umatilla Members (Saddle Mountains Basalt), Priest Rapids and Frenchman Springs Members (Wanapum Basalt), and Grande Ronde Basalt were erupted as fairly uniform sheets. The Wahluke and Huntzinger flows (Saddle Mountains Basalt) fill a paleovalley cut into Wanapum Basalt. No evidence was found to indicate Quaternary-age movement on any structures in the map area. The basalt strata on the south limb of the Umtanum anticline display relatively little tectonic deformation since Miocene-Pliocene time. Thus, the buried south flank of Umtanum Ridge may provide an excellent location for a nuclear waste repository beneath the Hanford Site.

Preliminary geology of eastern Umtanum Ridge, South-Central Washington

International Nuclear Information System (INIS)

Goff, F.E.

1981-01-01

The basalt stratigraphy and geologic structures of eastern Umtanum Ridge have been mapped and studied in detail to help assess the feasibility of nuclear waste terminal storage on the Hanford Site in southeastern Washington State. Eastern Umtanum Ridge is an asymmetric east-west-trending anticline of Columbia River basalt that plunges 5 degrees eastward into the Pasco Basin. Geologic mapping and determination of natural remanent magnetic polarity and chemical composition reveal that flows of the Pomona and Umatilla Members (Saddle Mountains Basalt), Priest Rapids and Frenchman Springs Members (Wanapum Basalt), and Grande Ronde Basalt were erupted as fairly uniform sheets. The Wahluke and Huntzinger flows (Saddle Mountains Basalt) fill a paleovalley cut into Wanapum Basalt. No evidence was found to indicate Quaternary-age movement on any structures in the map area. The basalt strata on the south limb of the Umtanum anticline display relatively little tectonic deformation since Miocene-Pliocene time. Thus, the buried south flank of Umtanum Ridge may provide an excellent location for a nuclear waste repository beneath the Hanford Site

Environmental geophysics: Locating and evaluating subsurface geology, geologic hazards, groundwater contamination, etc

International Nuclear Information System (INIS)

Benson, A.K.

1994-01-01

Geophysical surveys can be used to help delineate and map subsurface geology, including potential geologic hazards, the water table, boundaries of contaminated plumes, etc. The depth to the water table can be determined using seismic and ground penetrating radar (GPR) methods, and hydrogeologic and geologic cross sections of shallow alluvial aquifers can be constructed from these data. Electrical resistivity and GPR data are especially sensitive to the quality of the water and other fluids in a porous medium, and these surveys help to identify the stratigraphy, the approximate boundaries of contaminant plumes, and the source and amount of contamination in the plumes. Seismic, GPR, electromagnetic (VLF), gravity, and magnetic data help identify and delineate shallow, concealed faulting, cavities, and other subsurface hazards. Integration of these geophysical data sets can help pinpoint sources of subsurface contamination, identify potential geological hazards, and optimize the location of borings, monitoring wells, foundations for building, dams, etc. Case studies from a variety of locations will illustrate these points. 20 refs., 17 figs., 6 tabs

Historical tephra-stratigraphy of the Cosiguina Volcano (Western Nicaragua)

International Nuclear Information System (INIS)

Hradecky, Petr; Rapprich, Vladislav

2008-01-01

New detailed geological field studies and 14 C dating of the Cosiguina Volcano (westernmost Nicaragua) have allowed to reconstruct a geological map of the volcano and to establish a recent stratigraphy, including three historical eruptions. Five major sequences are represented. I: pyroclastic flows around 1500 AD, II: pyroclastic flows, scoria and pumice flows and surges, III: pyroclastic deposits related to a littoral crater, IV: pyroclastic flows related to 1709 AD eruption, and finally, V: pyroclastic deposits corresponding to the cataclysmic 1835 AD phreatic, phreatomagmatic and subplinian eruption, which seems to be relatively small-scale in comparison with the preceding historical eruptions. The pulsating geochemical character of the pyroclastic rocks in the last five centuries has been documented. The beginning of every eruption is marked by increasing contents of silica and Zr. Based on that, regardless of present-day volcanic repose, the entire Cosiguina Peninsula should be considered as a very hazardous volcanic area. (author)

Field-trip guide to the vents, dikes, stratigraphy, and structure of the Columbia River Basalt Group, eastern Oregon and southeastern Washington

Science.gov (United States)

Camp, Victor E; Reidel, Stephen P.; Ross, Martin E.; Brown, Richard J.; Self, Stephen

2017-06-22

The Columbia River Basalt Group covers an area of more than 210,000 km2 with an estimated volume of 210,000 km3. As the youngest continental flood-basalt province on Earth (16.7–5.5 Ma), it is well preserved, with a coherent and detailed stratigraphy exposed in the deep canyonlands of eastern Oregon and southeastern Washington. The Columbia River flood-basalt province is often cited as a model for the study of similar provinces worldwide.This field-trip guide explores the main source region of the Columbia River Basalt Group and is written for trip participants attending the 2017 International Association of Volcanology and Chemistry of the Earth’s Interior (IAVCEI) Scientific Assembly in Portland, Oregon, USA. The first part of the guide provides an overview of the geologic features common in the Columbia River flood-basalt province and the stratigraphic terminology used in the Columbia River Basalt Group. The accompanying road log examines the stratigraphic evolution, eruption history, and structure of the province through a field examination of the lavas, dikes, and pyroclastic rocks of the Columbia River Basalt Group.

Stratigraphy of amethyst geode-bearing lavas and fault-block structures of the Entre Rios mining district, Paraná volcanic province, southern Brazil

Directory of Open Access Journals (Sweden)

LÉO A. HARTMANN

2014-03-01

Full Text Available The Entre Rios mining district produces a large volume of amethyst geodes in underground mines and is part of the world class deposits in the Paraná volcanic province of South America. Two producing basalt flows are numbered 4 and 5 in the lava stratigraphy. A total of seven basalt flows and one rhyodacite flow are present in the district. At the base of the stratigraphy, beginning at the Chapecó river bed, two basalt flows are Esmeralda, low-Ti type. The third flow in the sequence is a rhyodacite, Chapecó type, Guarapuava subtype. Above the rhyodacite flow, four basalt flows are Pitanga, high-Ti type including the two mineralized flows; only the topmost basalt in the stratigraphy is a Paranapanema, intermediate-Ti type. Each individual flow is uniquely identified from its geochemical and gamma-spectrometric properties. The study of several sections in the district allowed for the identification of a fault-block structure. Blocks are elongated NW and the block on the west side of the fault was downthrown. This important structural characterization of the mining district will have significant consequences in the search for new amethyst geode deposits and in the understanding of the evolution of the Paraná volcanic province.

GIS-technologies as a mechanism to study geological structures

Science.gov (United States)

Sharapatov, Abish

2014-05-01

Specialized GIS-technologies allow creating multi-parameter models, completing multi-criteria optimisation tasks, and issues of geological profile forecasts using miscellaneous data. Pictorial and attributive geological and geophysical information collected to create GIS database is supplemented by the ERS (Earth's Remote Sensing) data, air spectrometry, space images, and topographic data. Among the important tasks are as follows: a unification of initial geological, geophysical and other types of information on a tectonic position, rock classification and stratigraphic scale; topographic bases (various projectures, scales); the levels of detail and exhaustibility; colors and symbols of legends; data structures and their correlation; units of measurement of physical quantities, and attribute systems of descriptions. Methods of the geological environment investigation using GIS-technology are based on a principle of the research target analogy with a standard. A similarity ratio is quantitative estimate. A geological forecast model is formed by structuring of geological information based on detailed analysis and aggregation of geological and formal knowledge bases on standard targets. Development of a bank of models of the analyzed geological structures of various range, ore-bearing features described by numerous prospecting indicators is the way to aggregate geological knowledge. The south terrain of the Valerianovskaya structure-facies zone (SFZ) of the Torgai paleo-rift structure covered with thick Mesozoic and Cenozoic rocks up to 2,000m is considered a so-called training ground for the development of GIS-technology. Parameters of known magnetite deposits located in the north of the SFZ (Sarybaiskoye, Sokolovskoye, etc.) are used to create the standard model. A meaning of the job implemented involves the following: - A goal-seeking nature of the research being performed and integration of the geological, geo-physical and other data (in many cases, efforts of the

Influence Of Geology On Pavement Performance: A Case Study Of ...

African Journals Online (AJOL)

Field and laboratory investigations which involved geologic mapping, auger boring, sampling and laboratory testing were carried out to determine the stratigraphy and geotechnical properties of the sub-grade and their relationship to the pavement condition. Field observation indicated that the road may have been based on ...

Stratigraphy of the late Cenozoic sediments beneath the 216-B and C crib facilities

International Nuclear Information System (INIS)

Fecht, K.R.; Last, G.V.; Marratt, M.C.

1979-02-01

The stratigraphy of the late Cenozoic sediments beneath the 216-B and C Crib Facilities is presented as lithofacies cross sections and is based on textural variations of the sedimentary sequence lying above the basalt bedrock. The primary source of data in this study is geologic information obtained from well drilling operations and geophysical logging. Stratigraphic interpretations are based primarily on textural analysis and visual examination of sediment samples and supplemented by drillers logs and geophysical logs

Report on technological achievements in fiscal 1999. Survey on geological structures in overseas countries, 'Japan-Vietnam joint coal exploration project on Red River delta'; 1999 nendo kaigai chishitsu kozo nado chosa hokokusho. Nippon Vietnam sekitan kyodo tansa Red River delta project

Energy Technology Data Exchange (ETDEWEB)

NONE

2000-06-01

With an objective to identify stratigraphy, geological structures, coal bed existing status, and coal quality of major coal beds in the north and central district of the area to be surveyed in the Red River delta, test well drilling, physical and seismic exploration, and coal composition analyses were performed. The area to be surveys is a typical delta where irrigation canals are running in all directions. Three test wells were drilled with drilling lengths of 640 m for TD3, 700 m for TD4 and 900 m for TD5. Coring was performed to depths greater than the Tertiary deposit. The seismic exploration was executed along three exploration lines. Total distance was 25 km. In addition, the VSP investigation was carried out on TD3 and TD5. The stratigraphy is composed from below of the Phu Cu bed (Neogene period: marine deposit) , the Tien Hung bed (Neogene period: continental deposit), and the Tai Doung bed (quaternary deposit), in which the bed that holds coal beds is the Tien Hung bed. The beds are very stable as the geological structure, but the constituting rocks are soft and fragile. Anticipated coal beds exist in depths greater than 1000 m. The coal quality is of low ash, low sulfur, medium in calorific power, and contains little gas. (NEDO)

Geology of the Spanish part of the Gavarnie Nappe (Pyrenees) and its underlying sediments near Bielsa (Province of Huesca)

NARCIS (Netherlands)

Lith, J.G.J. van

1968-01-01

A description is given of the stratigraphy and the tectonics of the Spanish part of the Gavarnie nappe and and its underlying sediments near Bielsa. The outlines of the geological map coincide approximately with the frontier of the municipality of Bielsa. This study forms part of geological

Geology and development: proceedings of the 40. Brazilian congress on geology; EXPOGEO 98 - Brazilian exposition of Geology. Abstracts

International Nuclear Information System (INIS)

1998-01-01

The proceedings of the 40. Brazilian Congress on Geology register relevant papers on the nuclear and energy areas. The papers devoted to the nuclear area covers the following subjects: geochronology; stratigraphy; geochemistry; age estimation; isotope dating; litogeochemistry; mineralization; uranium deposits; crystallization; environmental impacts related to the uranium mines and the non nuclear mining industries; petrogenesis; paleoclimatology; natural radioactivity; spectrometry; and the uranium extraction. The articles on the energy area are referent to the petroleum, coal and natural gas exploration; environmental impacts related to the oil spilling; and the history and the perspectives of the petroleum exploration in Brazil

High resolution sequence stratigraphy in China

International Nuclear Information System (INIS)

Zhang Shangfeng; Zhang Changmin; Yin Yanshi; Yin Taiju

2008-01-01

Since high resolution sequence stratigraphy was introduced into China by DENG Hong-wen in 1995, it has been experienced two development stages in China which are the beginning stage of theory research and development of theory research and application, and the stage of theoretical maturity and widely application that is going into. It is proved by practices that high resolution sequence stratigraphy plays more and more important roles in the exploration and development of oil and gas in Chinese continental oil-bearing basin and the research field spreads to the exploration of coal mine, uranium mine and other strata deposits. However, the theory of high resolution sequence stratigraphy still has some shortages, it should be improved in many aspects. The authors point out that high resolution sequence stratigraphy should be characterized quantitatively and modelized by computer techniques. (authors)

Persistent Tracers of Historic Ice Flow in Glacial Stratigraphy near Kamb Ice Stream, West Antarctica

OpenAIRE

Holschuh, Nicholas; Christianson, Knut; Conway, Howard; Jacobel, Robert W.; Welch, Brian C.

2018-01-01

Variations in properties controlling ice flow (e.g., topography, accumulation rate, basal friction) are recorded by structures in glacial stratigraphy. When anomalies that disturb the stratigraphy are fixed in space, the structures they produce advect away from the source, and can be used to trace flow pathways and reconstruct ice-flow patterns of the past. Here we provide an example of one of these persistent tracers: a prominent unconformity in the glacial layering that originates at Mt. Re...

Geological map of Uruguay Esc 1,100,000. Fuente del Puma Sheet G-27

International Nuclear Information System (INIS)

Preciozzi, F.; Pena, S.

1990-01-01

This work is about the geological map of Uruguay Esc.1.100.000 (Fuente del Puma) and the explanatory memoranda which describes the geological , lithological and sedimentological characteristics soils. The area corresponding to Fuente del Puma is located in the SW of Lavalleja and NW of Maldonado town and its stratigraphy belong to the Cretaceous and Cenozoic formations as well as the Cambrian and upper Precambrian

Three-dimensional Geological and Geo-mechanical Modelling of Repositories for Nuclear Waste Disposal in Deep Geological Structures

International Nuclear Information System (INIS)

Fahland, Sandra; Hofmann, Michael; Bornemann, Otto; Heusermann, Stefan

2008-01-01

To prove the suitability and safety of underground structures for the disposal of radioactive waste extensive geo-scientific research and development has been carried out by BGR over the last decades. Basic steps of the safety analysis are the geological modelling of the entire structure including the host rock, the overburden and the repository geometry as well as the geo-mechanical modelling taking into account the 3-D modelling of the underground structure. The geological models are generated using the special-construction openGEO TM code to improve the visualisation an d interpretation of the geological data basis, e.g. borehole, mine, and geophysical data. For the geo-mechanical analysis the new JIFE finite-element code has been used to consider large 3-D structures with complex inelastic material behaviour. To establish the finite-element models needed for stability and integrity calculations, the geological models are simplified with respect to homogenous rock layers with uniform material behaviour. The modelling results are basic values for the evaluation of the stability of the repository mine and the long-term integrity of the geological barrier. As an example of application, the results of geological and geo-mechanical investigations of the Morsleben repository based on 3-D modelling are presented. (authors)

The geology of the surrounding metamorphic rock of Zaer granite (Morocco): contribution to the search for uranium

International Nuclear Information System (INIS)

Mathias, Laurent

1984-01-01

This research thesis reports a study which aimed at reconstituting the geological history of the Zaer region in Morocco with objectives of mining exploration and of assessment of its uranium metallogenic potential. The author examined the whole geological context by studying stratigraphy, sedimentology, tectonic, and petrography of rocks belonging to the concerned area. The main objective was to determine the origin of uranium between a granitic one and a sedimentary one. This meant a reconstitution of the geological history, and therefore the study of the metamorphized sedimentary surrounding rock, of the intrusive granite and of their different possible relationships. On a first part, the author analysed outcropping formations and tried to assign them with a stratigraphic position. He also tried to define the deposition modalities of these formations which could have conditioned sedimentary sites. In a second part, the author reports the study of geological structures and tectonic in order to try to recognise possible structures which could have promoted uranium deposition and trapping in the surrounding rock as well as in granite. The last part addresses the petrography of the different rocks met in the area, and mineralization, notably that of uranium [fr

Geology of the U12n.07 UG-3 drill hole, area 12, Nevada Test Site

International Nuclear Information System (INIS)

Terry, S.S.; Cunningham, M.J.

1975-11-01

The U12n.07 UG-3 horizontal drill hole, located near the eastern edge of the center of Rainier Mesa, Nevada Test Site, was drilled to a total depth of 809 m (2,653 ft). This hole was drilled to further evaluate the tunnel-level stratigraph, and structure southwest of the U12n tunnel complex. The drill hole is collared in the middle of Tertiary tunnel bed 3A and penetrates upsection through tunnel beds 3 and 4 and terminates in subunit 4K, all of Tertiary age. Stratigraphy, structure, engineering geology, and physical properties and their relation to tunnel engineering are discussed

Process for structural geologic analysis of topography and point data

Science.gov (United States)

Eliason, Jay R.; Eliason, Valerie L. C.

1987-01-01

A quantitative method of geologic structural analysis of digital terrain data is described for implementation on a computer. Assuming selected valley segments are controlled by the underlying geologic structure, topographic lows in the terrain data, defining valley bottoms, are detected, filtered and accumulated into a series line segments defining contiguous valleys. The line segments are then vectorized to produce vector segments, defining valley segments, which may be indicative of the underlying geologic structure. Coplanar analysis is performed on vector segment pairs to determine which vectors produce planes which represent underlying geologic structure. Point data such as fracture phenomena which can be related to fracture planes in 3-dimensional space can be analyzed to define common plane orientation and locations. The vectors, points, and planes are displayed in various formats for interpretation.

The 1:3M geologic map of Mercury: progress and updates

Science.gov (United States)

Galluzzi, Valentina; Guzzetta, Laura; Mancinelli, Paolo; Giacomini, Lorenza; Malliband, Christopher C.; Mosca, Alessandro; Wright, Jack; Ferranti, Luigi; Massironi, Matteo; Pauselli, Cristina; Rothery, David A.; Palumbo, Pasquale

2017-04-01

After the end of Mariner 10 mission a 1:5M geologic map of seven of the fifteen quadrangles of Mercury [Spudis and Guest, 1988] was produced. The NASA MESSENGER mission filled the gap by imaging 100% of the planet with a global average resolution of 200 m/pixel and this led to the production of a global 1:15M geologic map of the planet [Prockter et al., 2016]. Despite the quality gap between Mariner 10 and MESSENGER images, no global geological mapping project with a scale larger than 1:5M has been proposed so far. Here we present the status of an ongoing project for the geologic mapping of Mercury at an average output scale of 1:3M based on the available MESSENGER data. This project will lead to a fuller grasp of the planet's stratigraphy and surface history. Completing such a product for Mercury is an important goal in preparation for the forthcoming ESA/JAXA BepiColombo mission to aid selection of scientific targets and to provide context for interpretation of new data. At the time of this writing, H02 Victoria [Galluzzi et al., 2016], H03 Shakespeare [Guzzetta et al., 2016] and H04 Raditladi [Mancinelli et al., 2016] have been completed and H05 Hokusai [Rothery et al., 2017], H06 Kuiper [Giacomini et al., 2017], H07 Beethoven and H10 Derain [Malliband et al., 2017] are being mapped. The produced geologic maps were merged using the ESRI ArcGIS software adjusting discontinuous contacts along the quadrangle boundaries. Contact discrepancies were reviewed and discussed among the mappers of adjoining quadrangles in order to match the geological interpretation and provide a unique consistent stratigraphy. At the current stage, more than 20% of Mercury has now a complete 1:3M map and more than 40% of the planet will be covered soon by the maps that are being prepared. This research was supported by the Italian Space Agency (ASI) within the SIMBIOSYS project (ASI-INAF agreement no. I/022/10/0). References Galluzzi V. et al. (2016). Geology of the Victoria Quadrangle (H

GIS Data Modeling of a Regional Geological Structure by Integrating Geometric and Semantic Expressions

Directory of Open Access Journals (Sweden)

HE Handong

2017-08-01

Full Text Available Using GIS, data models of geology via geometric descriptions and expressions are being developed. However, the role played by these data models in terms of the description and expression of geological structure phenomenon is limited. To improve the semantic information in geological GIS data models, this study adopts an object-oriented method that describes and expresses the geometric and semantic features of the geological structure phenomenon using geological objects and designs a data model of regional geological structures by integrating geometry and semantics. Moreover, the study designs a semantic "vocabulary-explanation-graph" method for describing the geological phenomenon of structures. Based on the semantic features of regional geological structures and a linear classification method, it divides the regional geological structure phenomenon into 3 divisions, 10 groups, 33 classes and defines the element set and element class. Moreover, it builds the basic geometric network for geological elements based on the geometric and semantic relations among geological objects. Using the ArcGIS Diagrammer Geodatabase, it considers the regional geological structure of the Ning-Zhen Mountains to verify the data model, and the results indicate a high practicability.

Abstracts of the Annual Meeting of Planetary Geologic Mappers, San Antonio, TX, 2009

Science.gov (United States)

Bleamaster, Leslie F., III (Editor); Tanaka, Kenneth L.; Kelley, Michael S.

2009-01-01

Topics covered include: Geologic Mapping of the Beta-Atla-Themis (BAT) Region of Venus: A Progress Report; Geologic Map of the Snegurochka Planitia Quadrangle (V-1): Implications for Tectonic and Volcanic History of the North Polar Region of Venus; Preliminary Geological Map of the Fortuna Tessera (V-2) Quadrangle, Venus; Geological Map of the Fredegonde (V-57) Quadrangle, Venus; Geological Mapping of the Lada Terra (V-56) Quadrangle, Venus; Geologic Mapping of V-19; Lunar Geologic Mapping: A Preliminary Map of a Portion of the LQ-10 ("Marius") Quadrangle; Geologic Mapping of the Lunar South Pole, Quadrangle LQ-30: Volcanic History and Stratigraphy of Schr dinger Basin; Geologic Mapping along the Arabia Terra Dichotomy Boundary: Mawrth Vallis and Nili Fossae, Mars; Geologic Mapping Investigations of the Northwest Rim of Hellas Basin, Mars; Geologic Mapping of the Meridiani Region of Mars; Geology of a Portion of the Martian Highlands: MTMs -20002, -20007, -25002 and -25007; Geologic Mapping of Holden Crater and the Uzboi-Ladon-Morava Outflow System; Mapping Tyrrhena Patera and Hesperia Planum, Mars; Geologic Mapping of Athabaca Valles; Geologic Mapping of MTM -30247, -35247 and -40247 Quadrangles, Reull Vallis Region, Mars Topography of the Martian Impact Crater Tooting; Mars Structural and Stratigraphic Mapping along the Coprates Rise; Geology of Libya Montes and the Interbasin Plains of Northern Tyrrhena Terra, Mars: Project Introduction and First Year Work Plan; Geology of the Southern Utopia Planitia Highland-Lowland Boundary Plain: Second Year Results and Third Year Plan; Mars Global Geologic Mapping: About Half Way Done; New Geologic Map of the Scandia Region of Mars; Geologic Mapping of the Medusae Fossae Formation on Mars and the Northern Lowland Plains of Venus; Volcanism on Io: Insights from Global Geologic Mapping; and Planetary Geologic Mapping Handbook - 2009.

The Andatza coarse-grained turbidite system (westernmost Pyrenees: Stratigraphy, sedimentology and structural control

Directory of Open Access Journals (Sweden)

A. Bodego

2017-06-01

Full Text Available This is a field-based work that describes the stratigraphy and sedimentology of the Andatza Conglomerate Formation. Based on facies analysis three facies associations of a coarse-grained turbidite system and the related slope have been identified: (1 an inner fan of a turbidite system (or canyon and (2 a low- and (3 a high-gradient muddy slope respectively. The spatial distribution of the facies associations and the palaeocurrent analysis allow to interpret a depositional model for the Andatza Conglomerates consisting of an L-shaped, coarse-grained turbidite system, whose morphology was structurally controlled by synsedimentary basement-involved normal faults. The coarse-grained character of the turbidite system indicates the proximity of the source area, with the presence of a narrow shelf that fed the turbidite canyon from the north.

Graptolite assemblages and stratigraphy of the lower Silurian Mrákotín Formation, Hlinsko Zone, NE interior of the Bohemian Massif (Czech Republic)

Czech Academy of Sciences Publication Activity Database

Štorch, Petr; Kraft, P.

2009-01-01

Roč. 84, č. 1 (2009), s. 51-74 ISSN 1214-1119 R&D Projects: GA AV ČR IAA3013405 Institutional research plan: CEZ:AV0Z30130516 Keywords : graptolites * stratigraphy * Llandovery * Hlinsko Zone * Bohemian Massif Subject RIV: DB - Geology ; Mineralogy Impact factor: 0.983, year: 2009

A reappraaisal of the geology, geochemistry, structures and ...

African Journals Online (AJOL)

The largest segment of the Neoproterozoic Mozambique belt in Kenya occurs east of the north-south oriented Rift system. Geological works carried out in the country during the last few decades have progressively revealed the complexity of the geology, structures and tectonics of the Mozambique belt in the region.

Local geological sections and regional stratigraphy based on physical geology and chemical stratigraphy of the Serra Geral Group from Araraquara to Avaré, SP

Directory of Open Access Journals (Sweden)

Amélia João Fernandes

2018-05-01

Full Text Available ABSTRACT: From Araraquara to Avaré, in the Serra Geral Group outcropping area, 22 detailed geological sections were elaborated. The stratigraphic relationships and the chemical analysis allowed the identification of seven [P2O5] basalt classes, all of them pertaining to the Pitanga type, showing a consistent stacking order across the studied region. Thus, each class is considered to correspond to a specific lava flow, allowing a general stratigraphic column to be proposed. Besides the stacking order, the validation of P2O5 as a tool for lava correlation at great distances was also based on the values obtained from samples collected at different positions in a single flow, and on the remarkable [P2O5] contrast between adjacent flows. Minimum lateral extensions range from 75 to 185 km, and thickness from 20 to 80 m. Vertical tectonic displacements, which took place in different periods, were inferred from the altitude of specific flows, and also from the Botucatu and Piramboia formations. They are noticeable in a region bounded by EW drainage lineaments, which contains a large area where Piramboia and Botucatu formations crop out, probably due to the tectonic activity causing this region to be a generalized structural high.

The genesis, stratigraphy and age of Finnish peat deposits. Soiden syntvy, rakenne ja ikae Suomessa

Energy Technology Data Exchange (ETDEWEB)

Glueckert, G [Turun yliopisto (Finland). Maaperaegeologian osasto

1986-01-01

The genesis, stratigraphy and age of Finnish peat deposits are briefly described. Finnish peats are classified according to their botanical composition to Sphagnum, sedge (Carex) and wood peats. They form complex types of peat land: the ombrotrophic raised bogs in southern Finland and the minerotrophic open sedge (aapa) bogs in northern Finland. The structural bog types in the geological classification are mainly composed of Sphagnum and Carex peats. The raised bogs are predominantly built up of Sphagnum peat, the aapa bogs of Carex peat. The bogs are formed by paludification of lakes, of rising coasts or of low-lying forests. The thickness of peat varies from 3 to 8 m in southern Finland and from 1 to 3 m in northern Finland. The age of the bogs varies according to the uplift of land and the altitude of the bog gasin above sea level. The oldest bogs are 9500-10000 years old and formed in southern and eastern Finland on high-lying upland tracts just after the retreat of the ice at the end of the last glaciation. The geological and palaeontological development of bogs and the history of climate and vegetation can be studied and dated pollenanalytically and with the radiocarbon method.

Stratigraphy of the Middle Devonian boundary: Formal definition of the susceptibility magnetostratotype in Germany with comparisons to sections in the Czech Republic, Morocco and Spain

Czech Academy of Sciences Publication Activity Database

Ellwood, B. B.; García-Alcalde, J. L.; El-Hasani, A.; Hladil, Jindřich; Soto, F. M.; Truylós-Massoni, M.; Weddige, K.; Koptíková, Leona

2006-01-01

Roč. 418, č. 1 (2006), s. 31-49 ISSN 0040-1951 R&D Projects: GA AV ČR(CZ) IAA3013406 Institutional research plan: CEZ:AV0Z30130516 Keywords : magnetic susceptibility * stratigraphy * high-resolution correlation Subject RIV: DB - Geology ; Mineralogy Impact factor: 1.675, year: 2006

Reference stratigraphy and rock properties for the Waste Isolation Pilot Plant (WIPP) project

International Nuclear Information System (INIS)

Krieg, R.D.

1984-01-01

A stratigraphic description of the country rock near the working horizon at the Waste Isolation Pilot Plant (WIPP) is presented along with a set of mechanical and thermal properties of materials involved. Data from 41 cores and shafts are examined. The entire stratigraphic section is found to vary in elevation in a regular manner, but individual layer thicknesses and relative separation between layers are found to have no statistically significant variation over the one mile north to south extent of the working horizon. The stratigraphic description is taken to be relative to the local elevation of Anhydrite b. The material properties have been updated slightly from those in the July 1981 Reference Stratigraphy. This reference stratigraphy/properties document is intended primarily for use in thermal/structural analyses. This document supercedes the July 1981 stratigraphy/properties document. 31 references, 7 figures

Spatial Abilities of High-School Students in the Perception of Geologic Structures.

Science.gov (United States)

Kali, Yael; Orion, Nir

1996-01-01

Characterizes specific spatial abilities required in geology studies through the examination of the performance of high school students in solving structural geology problems on the geologic spatial ability test (GeoSAT). Concludes that visual penetration ability and the ability to perceive the spatial configuration of the structure are…

Geologic investigation :an update of subsurface geology on Kirtland Air Force Base, New Mexico.

Energy Technology Data Exchange (ETDEWEB)

Van Hart, Dirk (GRAM, Inc.)

2003-06-01

The objective of this investigation was to generate a revised geologic model of Kirtland Air Force Base (KAFB) incorporating the geological and geophysical data produced since the Site-Wide Hydrogeologic Characterization Project (SWHC) of 1994 and 1995. Although this report has certain stand-alone characteristics, it is intended to complement the previous work and to serve as a status report as of late 2002. In the eastern portion of KAFB (Lurance Canyon and the Hubbell bench), of primary interest is the elevation to which bedrock is buried under a thin cap of alluvium. Elevation maps of the bedrock top reveal the paleodrainage that allows for the interpretation of the area's erosional history. The western portion of KAFB consists of the eastern part of the Albuquerque basin where bedrock is deeply buried under Santa Fe Group alluvium. In this area, the configuration of the down-to-the-west, basin-bounding Sandia and West Sandia faults is of primary interest. New geological and geophysical data and the reinterpretation of old data help to redefine the location and magnitude of these elements. Additional interests in this area are the internal stratigraphy and structure of the Santa Fe Group. Recent data collected from new monitoring wells in the area have led to a geologic characterization of the perched Tijeras Arroyo Groundwater system and have refined the known limits of the Ancestral Rio Grande fluvial sediments within the Santa Fe Group. Both the reinterpretation of the existing data and a review of the regional geology have shown that a segment of the boundary between the eastern and western portions of KAFB is a complicated early Tertiary (Laramide) wrench-fault system, the Tijeras/Explosive Ordnance Disposal Area/Hubbell Spring system. A portion of this fault zone is occupied by a coeval ''pull-apart'' basin filled with early Tertiary conglomerates, whose exposures form the ''Travertine Hills''.

Geologic map and map database of northeastern San Francisco Bay region, California, [including] most of Solano County and parts of Napa, Marin, Contra Costa, San Joaquin, Sacramento, Yolo, and Sonoma Counties

Science.gov (United States)

Graymer, Russell Walter; Jones, David Lawrence; Brabb, Earl E.

2002-01-01

This digital map database, compiled from previously published and unpublished data, and new mapping by the authors, represents the general distribution of bedrock and surficial deposits in the mapped area. Together with the accompanying text file (nesfmf.ps, nesfmf.pdf, nesfmf.txt), it provides current information on the geologic structure and stratigraphy of the area covered. The database delineates map units that are identified by general age and lithology following the stratigraphic nomenclature of the U.S. Geological Survey. The scale of the source maps limits the spatial resolution (scale) of the database to 1:62,500 or smaller.

Geological study of Ujungwatu area as support for NPP planning in Muria Central Java

International Nuclear Information System (INIS)

Srijono

1995-01-01

In accordance with growth of life in Java, the need for electricity is also growing accordingly. Efforts to provide electricity such as planning to build nuclear power plant (NPP) has been in the debate for a while. There are many factors to be considered in this planning, such as its environmental condition. Geological factor is one of the important one to be considered. Surface geological conditions around NPP area at Ujungwatu needed include stratigraphy, geological structure, geomorphology, and environmental geology. Geology in Ujungwatu at radius 5 km is quite interesting. This area is part of Genuk volcano group which is laid at south and Ujungwatu coast at north. Genuk mountain group is divided into mountain slope, mountain back, and mountain skeleton. Coastal area is composed of coast sand. Sand up to broken rock was present along river gullies. Others were volcanic rocks which was composed of lapili tuff, trachite, pyroxene andesite, tuff breccia, tephrite-andesitic tuff breccia, and basaltic tuff breccia. Volcanic structure is well reflected by morphological feature as lineaments and half circular form in mount Genuk. This structure was predominantly in NW-SE direction, and less dominant in NE-SW direction. Ujungwatu, from environmental view, is deserved to be developed because of its underground potency. Iron sand, fluvial tuff, kaolin, mud, riverstone, volcanic rock, tuff and marble were easily found underground. Those could be benefited to the people in the area so that it could change socio-economical condition of the people which in turn electricity is becoming a necessity. Last but not least, Portuguese fort as potential touristic object is also situated at Kartini beach near Ujungwatu. (author). 15 refs, 3 tabs, 5 figs

Minutes

International Nuclear Information System (INIS)

1998-01-01

In the minutes of II Uruguayan Geological Congress have been included the following topics: structural geology, tectonic, sedimentology, stratigraphy, mineralogy, petrology, geochemistry, paleontology, mineral prospecting, economic, regional and applied geology. (author)

Geology of kilauea volcano

Science.gov (United States)

Moore, R.B.; Trusdell, F.A.

1993-01-01

This paper summarizes studies of the structure, stratigraphy, petrology, drill holes, eruption frequency, and volcanic and seismic hazards of Kilauea volcano. All the volcano is discussed, but the focus is on its lower cast rift zone (LERZ) because active exploration for geothermal energy is concentrated in that area. Kilauea probably has several separate hydrothermal-convection systems that develop in response to the dynamic behavior of the volcano and the influx of abundant meteoric water. Important features of some of these hydrothermal-convection systems are known through studies of surface geology and drill holes. Observations of eruptions during the past two centuries, detailed geologic mapping, radiocarbon dating, and paleomagnetic secular-variation studies indicate that Kilauea has erupted frequently from its summit and two radial rift zones during Quaternary time. Petrologic studies have established that Kilauea erupts only tholeiitic basalt. Extensive ash deposits at Kilauea's summit and on its LERZ record locally violent, but temporary, disruptions of local hydrothermal-convection systems during the interaction of water or steam with magma. Recent drill holes on the LERZ provide data on the temperatures of the hydrothermal-convection systems, intensity of dike intrusion, porosity and permeability, and an increasing amount of hydrothermal alteration with depth. The prehistoric and historic record of volcanic and seismic activity indicates that magma will continue to be supplied to deep and shallow reservoirs beneath Kilauea's summit and rift zones and that the volcano will be affected by eruptions and earthquakes for many thousands of years. ?? 1993.

Proceedings of the second symposium on the geology of Rocky Mountain coal, 1977

Energy Technology Data Exchange (ETDEWEB)

Hodgson, H. E. [ed.

1978-01-01

The 1977 Symposium on the Geology of Rocky Mountain Coal was held May 9 and 10 on the campus of the Colorado School of Mines in Golden, Colorado. The 1977 Symposium was sponsored by the Colorado Geological Survey and the US Geological Survey. The 1977 Symposium consisted of four technical sessions: Depositional Models for Coal Exploration in the Rocky Mountain Cretaceous; Stratigraphy and Depositional Environments of Rocky Mountain Tertiary Coal Deposits; Depositional Models for Coal Exploration in non-Rocky Mountain Regions; and Application of Geology to Coal Mining and Coal Mine Planning. Several papers discuss geophysical survey and well logging techniques applied to the exploration of coal deposits and for mine planning. Fouteen papers have been entered individually into EDB and ERA. (LTN)

Geologic history of the Slick Rock district and vicinity, San Miguel and Dolores Counties, Colorado

International Nuclear Information System (INIS)

Shawe, D.R.

1976-01-01

This report is a narrative summary and interpretation, in the form of a geologic history of the Slick Rock district and vicinity, of four previously published chapters in this series dealing with stratigraphy of the Slick Rock district and vicinity, petrography of sedimentary rocks of the district, structure of the district and vicinity, and altered sedimentary rocks of the district, and of other previously published reports on the district. It forms the background, with the earlier reports, for presentation of a final report in the series describing the uranium-vanadium ore deposits. A review of the origin of sedimentary rocks and geologic history of the region indicates that formation of uranium-vanadium deposits was a natural result of the deposition of th rocks, the occurrence of intrastratal waters therein, and the post-depositional movement of the waters resulting from evolution of the sedimentary rock environment. 31 refs

Seismic stratigraphy and regional unconformity analysis of Chukchi Sea Basins

Science.gov (United States)

Agasheva, Mariia; Karpov, Yury; Stoupakova, Antonina; Suslova, Anna

2017-04-01

) progressed from south to north. It indicates the source area was Wrangel Herald arch. Horizon LCU lies on chaotic reflectance sequence of basement in South Chukchi profiles. It is matches to the geological structure in Hope basin Alaska. Cretaceous and Paleogene strata divided by Mid-Brooks unconformity that accompanied with intensive uplift and erosion. Paleogene sequence is characterized by high thickness in North Chukchi basin in comparison with Hanna Trough and North Slope basins. Prograding Paleogene thick clinoform units of various geometries, angular and trajectories are observed in North Chukchi basin. Thick clinoform sequences could be formed as a result of significant subsidence followed by rapid sedimentary influx. This model assumes that North Chukchi basin could be more affected by Cenozoic tectonics of Eurasia Basin rifting. Complementary studies will be connected with careful clinoform types mapping in combination with sequence stratigraphy analyses to identify the depositional environment, source rocks and reservoirs distribution. [1] Moore, T.E., Wallace, W.K., Bird, K.J., Karl, S.M., Mull, C.G. & Dillon, J.T. (1994) Geology of northern Alaska. In:The Geology of Alaska (Ed. by G. Plafker & H.C. Berg), Geol. Soc. Am., Geol.North America, G-1, 49-140.

Geology of the UE12t No. 3 vertical drill hole, area 12, Nevada Test Site

International Nuclear Information System (INIS)

Terry, S.S.

1975-11-01

The UE12t No. 3 vertical drill hole, located near the north end of Rainier Mesa, was drilled to a total depth of 663 m (2,176 ft). The UE12t No. 3 vertical hole was drilled to further evaluate the subsurface stratigraphy northwest of the t-tunnel complex area in preparation for mining of the U12t.03 (Husky Pup) drift. The drill hole is collared in the Rainier Mesa Member of the Timber Mountain Tuff and penetrates down the stratigraphic section through the Paintbrush Tuff, the welded Grouse Canyon Member of the Belted Range Tuff, tunnel beds 5-3, the Tub Spring Member of the Belted Range Tuff, tunnel bed 2, Crater Flat Tuff, tunnel bed 1, Redrock Valley Tuff, and bottoms in older Tertiary tuffaceous and Paleozoic quartzite rubble having a partially argillized, tuffaceous, soillike matrix. The tuff of Dead Horse Flat and the bedded and ash-flow tuffs of Area 20 were not differentiated in the logging of this drill hole. Stratigraphy, structure, engineering geology, and physical properties and their relation to tunneling are discussed

Structural styles and zircon ages of the South Tianshan accretionary complex, Atbashi Ridge, Kyrgyzstan: Insights for the anatomy of ocean plate stratigraphy and accretionary processes

Science.gov (United States)

Sang, Miao; Xiao, Wenjiao; Orozbaev, Rustam; Bakirov, Apas; Sakiev, Kadyrbek; Pak, Nikolay; Ivleva, Elena; Zhou, Kefa; Ao, Songjian; Qiao, Qingqing; Zhang, Zhixin

2018-03-01

The anatomy of an ancient accretionary complex has a significance for a better understanding of the tectonic processes of accretionary orogens and complex because of its complicated compositions and strong deformation. With a thorough structural and geochronological study of a fossil accretionary complex in the Atbashi Ridge, South Tianshan (Kyrgyzstan), we analyze the structure and architecture of ocean plate stratigraphy in the western Central Asian Orogenic Belt. The architecture of the Atbashi accretionary complex is subdivisible into four lithotectonic assemblages, some of which are mélanges with "block-in-matrix" structure: (1) North Ophiolitic Mélange; (2) High-pressure (HP)/Ultra-high-pressure (UHP) Metamorphic Assemblage; (3) Coherent & Mélange Assemblage; and (4) South Ophiolitic Mélange. Relationships between main units are tectonic contacts presented by faults. The major structures and lithostratigraphy of these units are thrust-fold nappes, thrusted duplexes, and imbricated ocean plate stratigraphy. All these rock units are complicatedly stacked in 3-D with the HP/UHP rocks being obliquely southwestward extruded. Detrital zircon ages of meta-sediments provide robust constraints on their provenance from the Ili-Central Tianshan Arc. The isotopic ages of the youngest components of the four units are Late Permian, Early-Middle Triassic, Early Carboniferous, and Early Triassic, respectively. We present a new tectonic model of the South Tianshan; a general northward subduction polarity led to final closure of the South Tianshan Ocean in the End-Permian to Late Triassic. These results help to resolve the long-standing controversy regarding the subduction polarity and the timing of the final closure of the South Tianshan Ocean. Finally, our work sheds lights on the use of ocean plate stratigraphy in the analysis of the tectonic evolution of accretionary orogens.

The geology of the Vicentinian Alps (NE-Italy) : (with special reference to their paleomagnetic history)

NARCIS (Netherlands)

Boer, J. de

1963-01-01

This geological study on the Vicentinian Alps is mainly an analysis of the tectonic and paleomagnetic data, collected by the author in the years 1959, 1960, and 1961. The stratigraphy is based for the greater part on data published in the first decenniums of this century. In the

The geology of the Vicentinian Alps (NE-Italy) : with special reference to their paleomagnetic history

NARCIS (Netherlands)

Boer, Jelle de

1963-01-01

This geological study on the Vicentinian Alps is mainly an analysis of the tectonic and paleomagnetic data, collected by the author in the years 1959, 1960, and 1961. The stratigraphy is based for the greater part on data published in the first decenniums of this century. In the

The STRATAFORM Project: U.S. Geological Survey geotechnical studies

Science.gov (United States)

Minasian, Diane L.; Lee, Homa J.; Locat, Jaques; Orzech, Kevin M.; Martz, Gregory R.; Israel, Kenneth

2001-01-01

This report presents physical property logs of core samples from an offshore area near Eureka, CA. The cores were obtained as part of the STRATAFORM Program (Nittrouer and Kravitz, 1995, 1996), a study investigating how present sedimentation and sediment transport processes influence long-term stratigraphic sequences preserved in the geologic record. The core samples were collected during four separate research cruises to the northern California study area, and data shown in the logs of the cores were collected using a multi-sensor whole core logger. The physical properties collected are useful in identifying stratigraphic units, ground-truthing acoustic imagery and sub-bottom profiles, and in understanding mass movement processes. STRATA FORmation on Margins was initiated in 1994 by the Office of Naval Research, Marine Geology and Geophysics Department as a coordinated multi-investigator study of continental-margin sediment transport processes and stratigraphy (Nittrouer and Kravitz, 1996). The program is investigating the stratigraphic signature of the shelf and slope parts of the continental margins, and is designed to provide a better understanding of the sedimentary record and a better prediction of strata. Specifically, the goals of the STRATAFORM Program are to (Nittrouer and Kravitz, 1995): - determine the geological relevance of short-term physical processes that erode, transport, and deposit particles and those processes that subsequently rework the seabed over time scales - improve capabilities for identifying the processes that form the strata observed within the upper ~100 m of the seabed commonly representing 104-106 years of sedimentation. - synthesize this knowledge and bridge the gap between time scales of sedimentary processes and those of sequence stratigraphy. The STRATAFORM Program is divided into studies of the continental shelf and the continental slope; the geotechnical group within the U.S. Geological Survey provides support to both parts

Reconnaissance Geology and Structure of the Coso Range, California.

Science.gov (United States)

1982-05-01

annual rainfall is slightly more than 2 inches in the valleys and 5 to 6 inches in the uplands; precipitation falls mostly from October through March...and Western Nevada. 1970. P. 42. (U.S. Geological Survey Professional Paper 623, UNCLASSIFIED.) 6 H. E. von Heiene. "Structural Geology and Gravimetry

Iapetus: Tectonic structure and geologic history

Science.gov (United States)

Croft, Steven K.

1991-01-01

Many papers have been written about the surface of Iapetus, but most of these have discussed either the nature of the strongly contrasting light and dark materials or the cratering record. Little has been said about other geologic features on Iapetus, such as tectonic structures, which would provide constraints on Iapetus' thermal history. Most references have suggested that there is no conclusive evidence for any tectonic activity, even when thermal history studies indicate that there should be. However, a new study of Iapetus' surface involving the use of stereo pairs, an extensive tectonic network has been recognized. A few new observations concerning the craters and dark material were also made. Thus the geology and geologic history of Iapetus can be more fully outlined than before. The tectonic network is shown along with prominent craters and part of the dark material in the geologic/tectonic sketch map. The topology of crater rims and scarps are quite apparent and recognizable in the different image pairs. The heights and slopes of various features given are based on comparison with the depths of craters 50 to 100 km in diameter, which are assumed to have the same depths as craters of similar diameter on Rhea and Titania.

Mare Crisium - Regional stratigraphy and geologic history. [from spectral reflectivities of Lunik 24 samples

Science.gov (United States)

Adams, J. B.; Head, J. W., III; Mccord, T. B.; Pieters, C.; Zisk, S.

1978-01-01

Spectral reflectance measurements of five Luna 24 samples and new telescopic reflectance spectra of 10-20 km areas of seven sites in Mare Crisium have been used to calibrate multispectral images of mare units. Based on these data, three major mare units are defined in the Crisium basin and their stratigraphy is interpreted. The oldest mare unit is exposed in the ejecta of the craters Picard and Peirce and along the outer edge of the southeastern part of the basin. The next younger unit includes the Luna 24 site and generally follows a topographic annulus along the basin margin. The youngest mare unit occupies the central part of the basin. It is concluded that subsidence occurred throughout the emplacement of mare units, including extensive warping and downfaulting of the inner part of the Crisium basin.

Remanent magnetization stratigraphy of lunar cores

Science.gov (United States)

Banerjee, S. K.; Gingrich, D.; Marvin, J. A.

1977-01-01

Depth dependent fluctuations have been observed in the natural remanent magnetizations (NRM) of drive cores and drill strings from Apollo 16 and 17 missions. Partial demagnetization of unstable secondary magnetizations and identification of characteristic error signals from a core which is known to have been recently disturbed allow us to identify and isolate the stable NRM stratigraphy in double drive core 60010/60009 and drill strings 60002-60004. The observed magnetization fluctuations persist after normalization to take into account depth dependent variations in the carriers of stable NRM. We tentatively ascribe the stable NRM stratigraphy to instantaneous records of past magnetic fields at the lunar surface and suggest that the stable NRM stratigraphy technique could develop as a new relative time-stratigraphic tool, to be used with other physical measurements such as relative intensity of ferromagnetic resonance and charged particle track density to study the evolution of the lunar regolith.

East Greenland Caledonides: stratigraphy, structure and geochronology: Lower Palaeozoic stratigraphy of the East Greenland Caledonides

Directory of Open Access Journals (Sweden)

Smith, M. Paul

2004-12-01

Full Text Available The Lower Palaeozoic stratigraphy of the East Greenland Caledonides, from the fjord region of North-East Greenland northwards to Kronprins Christian Land, is reviewed and a number of new lithostratigraphical units are proposed. The Slottet Formation (new is a Lower Cambrian quartzite unit, containing Skolithos burrows, that is present in the Målebjerg and Eleonore Sø tectonic windows, in the nunatak region of North-East Greenland. The unit is the source of common and often-reported glacial erratic boulders containing Skolithos that are distributed throughout the fjord region. The Målebjerg Formation (new overlies the Slottet Formation in the tectonic windows, and comprises limestones and dolostones of assumed Cambrian–Ordovician age. The Lower Palaeozoic succession of the fjord region of East Greenland (dominantly limestones and dolostones is formally placed in the Kong Oscar Fjord Group (new. Amendments are proposed for several existing units in the Kronprins Christian Land and Lambert Land areas, where they occur in autochthonous, parautochthonous and allochthonous settings.

Bacterial community structure in aquifers corresponds to stratigraphy

Science.gov (United States)

Beyer, Andrea; Möller, Silke; Neumann, Stefan; Burow, Katja; Gutmann, Falko; Lindner, Julia; Müsse, Steffen; Kothe, Erika; Büchel, Georg

2014-05-01

So far, groundwater microbiology with respect to different host rocks has not been well described in the literature. However, factors influencing the communities would be of interest to provide a tool for mapping groundwater paths. The Thuringian Basin (Germany) studied here, contains formations of the Permian (Zechstein) and also Triassic period of Buntsandstein, Muschelkalk and Keuper, all of which can be found to crop out at the surface in different regions. We analyzed the bacterial community of nine natural springs and sixteen groundwater wells of the respective rock formations as well as core material from the Zechstein salts. For that we sampled in a mine 3 differnet salt rock samples (carnallitite, halite and sylvinitite). To validate the different approaches, similar rock formations were compared and a consistent microbial community for Buntsandstein could be verified. Similary, for Zechstein, the presence of halophiles was seen with cultivation, isolation directly from the rock material and also in groundwater with DNA-dependent approaches. A higher overlap between sandstone- and limestone-derived communities was visible as if compared to the salt formations. Principal component analysis confirmed formation specific patterns for Muschelkalk, Buntsandstein and Zechstein for the bacterial taxa present, with some overlaps. Bacilli and Gammaproteobacteria were the major groups, with the genera Pseudomonas, Marinomonas, Bacillus, Marinobacter and Pseudoalteromonas representing the communities. The bacteria are well adapted to their respective environment with survival strategies including a wide range of salinity which makes them suitable as tracers for fluid movement below the ground. The results indicate the usefulness and robustness of the approach taken here to investigate aquifer community structures in dependence of the stratigraphy of the groundwater reservoir.

Geological Structures Mapping of Bukit Bunuh using 2-D Resistivity Imaging Method

Science.gov (United States)

Nur Amalina, M. K. A.; Nordiana, M. M.; Rahman, Nazrin; Saidin, Mokhtar; Masnan, S. S. K.

2018-04-01

The geological area of Bukit Bunuh is very complex due to the meteorite impact that has occurred millions years ago at Lenggong, Perak. The lithology of the study area consists of alluvium, tephra dust, and granitic rock. The geological contact, fault and fracture zone were found at the study area may indicate the geological process that undergoes at a place locally or regionally. These important features have led to the further research on 2-D resistivity imaging method (2-D RIM) to study the geological features. This method can provide the subsurface image that will delineate the geological structures. The surveys include three separate lines of different length which depend on the accessibility. The surveys were done by using Pole-Dipole array and 10 m of electrodes spacing. The objectives of this research are to determine the subsurface geological contact and to determine the existence of fault/fracture zones at the contact zone. The results from 2-D inversion profiles have successfully signified the types of geological structural such as fault, contact, and fractures. Hence, the results from 2-D RIM were used to draw the geological lineaments of Bukit Bunuh. The discontinuity of the lineaments may indicate the structures present.

ON DISCRETE STRUCTURE OF GEOLOGIC MEDIUM AND CONTINUAL APPROACH TO MODELING ITS MOVEMENTS

OpenAIRE

Sh. A. Mukhamediev

2016-01-01

This paper discusses the structure of a geologic medium represented by accessible lithified rocks and provides an overview of methods used to describe its movements. Two basic opinions are considered in the framework of the discussion: (1) an initially homogeneous and continuous geologic medium acquires the structure composed of blocks in the process of the geologic medium’s deformation/destruction/degradation, and (2) a geologic medium is composed of blocks (and often has hierarchic, active,...

Semantic Web-based digital, field and virtual geological

Science.gov (United States)

Babaie, H. A.

2012-12-01

in the stack assembles a set of polygonal (e.g., formation, member, intrusion), linear (e.g., fault, contact), and/or point (e.g., sample or measurement site) geological elements. These feature classes, represented in domain ontologies by classes, have their own sets of property (attribute, association relation) and topological (e.g., overlap, adjacency, containment), and network (cross-cuttings; connectivity) relationships. Since geological mapping involves describing and depicting different aspects of each feature class (e.g., contact, formation, structure), the same geographic region may be investigated by different communities, for example, for its stratigraphy, rock type, structure, soil type, and isotopic and paleontological age, using sets of ontologies. These data can become interconnected applying the Semantic Web technologies, on the Linked Open Data Cloud, based on their underlying common geographic coordinates. Sets of geological data published on the Cloud will include multiple RDF links to Cloud's geospatial nodes such as GeoNames and Linked GeoData. During mapping, a device such as smartphone, laptop, or iPad, with GPS and GIS capability and a DBpedia Mobile client, can use the current position to discover and query all the geological linked data, and add new data to the thematic layers and publish them to the Cloud.

The State Geologic Map Compilation (SGMC) geodatabase of the conterminous United States

Science.gov (United States)

Horton, John D.; San Juan, Carma A.; Stoeser, Douglas B.

2017-06-30

The State Geologic Map Compilation (SGMC) geodatabase of the conterminous United States (https://doi. org/10.5066/F7WH2N65) represents a seamless, spatial database of 48 State geologic maps that range from 1:50,000 to 1:1,000,000 scale. A national digital geologic map database is essential in interpreting other datasets that support numerous types of national-scale studies and assessments, such as those that provide geochemistry, remote sensing, or geophysical data. The SGMC is a compilation of the individual U.S. Geological Survey releases of the Preliminary Integrated Geologic Map Databases for the United States. The SGMC geodatabase also contains updated data for seven States and seven entirely new State geologic maps that have been added since the preliminary databases were published. Numerous errors have been corrected and enhancements added to the preliminary datasets using thorough quality assurance/quality control procedures. The SGMC is not a truly integrated geologic map database because geologic units have not been reconciled across State boundaries. However, the geologic data contained in each State geologic map have been standardized to allow spatial analyses of lithology, age, and stratigraphy at a national scale.

Structure, stratigraphy, and petroleum geology of the Little Plain basin, northwestern Hungary

Science.gov (United States)

Mattick, R.E.; Teleki, P.G.; Phillips, R.L.; Clayton, J.L.; David, G.; Pogcsas, G.; Bardocz, B.; Simon, E.

1996-01-01

The basement of the Little Plain (Kisalfo??ld) basin is composed of two parts: an eastern part comprised of folded and overthrusted Triassic and Paleozoic rocks of the Pelso block (Transdanubian Central Range) compressed in the Early Cretaceous, and a western part consisting of stacked nappes of the Austroalpine zone of Paleozoic rocks, significantly metamorphosed during Cretaceous and later compression, overriding Jurassic oceanic rift-zone rocks of the Penninic zone. The evolution of the basin began in the late Karpatian-early Badenian (middle Miocene) when the eastern part of the basin began to open along conjugate sets of northeast- and northwest-trending normal faults. Neogene rocks in the study area, on the average, contain less than 0.5 wt. % total organic carbon (TOC) and, therefore, are not considered effective source rocks. Locally, however, where TOC values are as high as 3 wt. %, significant amounts of gas may have been generated and expelled. Although potential stratigraphic traps are numerous in the Neogene section, these potential traps must be downgraded because of the small amount of hydrocarbons discovered in structural traps to date. With the exception of the Cretaceous, the Mesozoic section has not been actively explored. Large anticlinal and overthrust structures involving pre-Cretaceous strata remain undrilled.

Muon Tomography for Geological Repositories.

Science.gov (United States)

Woodward, D.; Kudryavtsev, V.; Gluyas, J.; Clark, S. J.; Thompson, L. F.; Klinger, J.; Spooner, N. J.; Blackwell, T. B.; Pal, S.; Lincoln, D. L.; Paling, S. M.; Mitchell, C. N.; Benton, C.; Coleman, M. L.; Telfer, S.; Cole, A.; Nolan, S.; Chadwick, P.

2015-12-01

Cosmic-ray muons are subatomic particles produced in the upper atmosphere in collisions of primary cosmic rays with atoms in air. Due to their high penetrating power these muons can be used to image the content (primarily density) of matter they pass through. They have already been used to image the structure of pyramids, volcanoes and other objects. Their applications can be extended to investigating the structure of, and monitoring changes in geological formations and repositories, in particular deep subsurface sites with stored CO2. Current methods of monitoring subsurface CO2, such as repeat seismic surveys, are episodic and require highly skilled personnel to operate. Our simulations based on simplified models have previously shown that muon tomography could be used to continuously monitor CO2 injection and migration and complement existing technologies. Here we present a simulation of the monitoring of CO2 plume evolution in a geological reservoir using muon tomography. The stratigraphy in the vicinity of the reservoir is modelled using geological data, and a numerical fluid flow model is used to describe the time evolution of the CO2 plume. A planar detection region with a surface area of 1000 m2 is considered, at a vertical depth of 776 m below the seabed. We find that one year of constant CO2 injection leads to changes in the column density of about 1%, and that the CO2 plume is already resolvable with an exposure time of less than 50 days. The attached figure show a map of CO2 plume in angular coordinates as reconstructed from observed muons. In parallel with simulation efforts, a small prototype muon detector has been designed, built and tested in a deep subsurface laboratory. Initial calibrations of the detector have shown that it can reach the required angular resolution for muon detection. Stable operation in a small borehole within a few months has been demonstrated.

The geology of the Vicentinian Alps (NE-Italy) : (with special reference to their paleomagnetic history)

NARCIS (Netherlands)

de Boer, J.

1963-01-01

This geological study on the Vicentinian Alps is mainly an analysis of the tectonic and paleomagnetic data, collected by the author in the years 1959, 1960, and 1961. The stratigraphy is based for the greater part on data published in the first decenniums of this century. In the westtern part of the

Methods for Enhancing Geological Structures in Spectral Spatial Difference－Based on Remote-Sensing Image

Institute of Scientific and Technical Information of China (English)

无

2000-01-01

@@In this paper, some image processing methods such as directional template (mask) matching enhancement, pseudocolor or false color enhancement, K-L transform enhancement are used to enhance a geological structure, one of important ore-controlling factors, shown in the remote-sensing images.This geological structure is regarded as image anomaly in the remote-sensing image, since considerable differences, based on the spatial spectral distribution pattern, in gray values (spectral), color tones and texture, are always present between the geological structure and background. Therefore,the enhancement of the geological structure in the remotesensing image is that of the spectral spatial difference.

Definition imaging of anomalous geologic structure with radio waves

International Nuclear Information System (INIS)

Stolarczyk, L.G.

1990-01-01

Diamond core drilling from the surface and access drifts are routinely used in acquiring subsurface geologic data. Examination of core from a constellation of drillholes enables the characterization of the prevailing geology in the deposit. Similar geologic members in adjacent drillholes suggest that layered rock continuity exists between drillholes. Mineralogical and physical examination of core along with computer generated stratigraphic cross sections graphically represents the correlation and classification of the rock in the deposit. CW radio waves propagating on ray paths between drillholes have been used to validate the stratigraphic cross section and image anomalous geologic structure between drillholes. This paper compares the crosshole radio wave tomography images of faults in a nuclear waste repository site and a coal seam with the in-mine mapping results

Study on high-resolution sequence stratigraphy framework of uranium-hosting rock series in Qianjiadian sag

International Nuclear Information System (INIS)

Chen Fanghong; Zhang Mingyu

2005-01-01

The ore-hosting Yaojia Formation is composed of a set of braided stream medium-fine grained sediments. Guided by the basic theory of high-resolution sequence stratigraphy, and based on the core observation, the analysis of chemical composition of rocks, and data of natural potential logging and apparent resistivity logging, the authors have set up the high-resolution sequence stratigraphy framework of the ore-hosting Yaojia Formation, and discussed the relation of the stratigraphic structure of the middle cycle, as well as the paleotopography, the micro-facies to the formation of uranium deposit. (authors)

Bayesian Chance-Constrained Hydraulic Barrier Design under Geological Structure Uncertainty.

Science.gov (United States)

Chitsazan, Nima; Pham, Hai V; Tsai, Frank T-C

2015-01-01

The groundwater community has widely recognized geological structure uncertainty as a major source of model structure uncertainty. Previous studies in aquifer remediation design, however, rarely discuss the impact of geological structure uncertainty. This study combines chance-constrained (CC) programming with Bayesian model averaging (BMA) as a BMA-CC framework to assess the impact of geological structure uncertainty in remediation design. To pursue this goal, the BMA-CC method is compared with traditional CC programming that only considers model parameter uncertainty. The BMA-CC method is employed to design a hydraulic barrier to protect public supply wells of the Government St. pump station from salt water intrusion in the "1500-foot" sand and the "1700-foot" sand of the Baton Rouge area, southeastern Louisiana. To address geological structure uncertainty, three groundwater models based on three different hydrostratigraphic architectures are developed. The results show that using traditional CC programming overestimates design reliability. The results also show that at least five additional connector wells are needed to achieve more than 90% design reliability level. The total amount of injected water from the connector wells is higher than the total pumpage of the protected public supply wells. While reducing the injection rate can be achieved by reducing the reliability level, the study finds that the hydraulic barrier design to protect the Government St. pump station may not be economically attractive. © 2014, National Ground Water Association.

Geology of Kilauea volcano

Energy Technology Data Exchange (ETDEWEB)

Moore, R.B. (Geological Survey, Denver, CO (United States). Federal Center); Trusdell, F.A. (Geological Survey, Hawaii National Park, HI (United States). Hawaiian Volcano Observatory)

1993-08-01

This paper summarizes studies of the structure, stratigraphy, petrology, drill holes, eruption frequency, and volcanic and seismic hazards of Kilauea volcano. All the volcano is discussed, but the focus is on its lower east rift zone (LERZ) because active exploration for geothermal energy is concentrated in that area. Kilauea probably has several separate hydrothermal-convection systems that develop in response to the dynamic behavior of the volcano and the influx of abundant meteoric water. Important features of some of these hydrothermal-convection systems are known through studies of surface geology and drill holes. Observations of eruptions during the past two centuries, detailed geologic mapping, radiocarbon dating, and paleomagnetic secular-variation studies indicate that Kilauea has erupted frequently from its summit and two radial rift zones during Quaternary time. Petrologic studies have established that Kilauea erupts only tholeiitic basalt. Extensive ash deposits at Kilauea's summit and on its LERZ record locally violent, but temporary, disruptions of local hydrothermal-convection systems during the interaction of water or steam with magma. Recent drill holes on the LERZ provide data on the temperatures of the hydrothermal-convection systems, intensity of dike intrusion, porosity and permeability, and an increasing amount of hydrothermal alteration with depth. The prehistoric and historic record of volcanic and seismic activity indicates that magma will continue to be supplied to deep and shallow reservoirs beneath Kilauea's summit and rift zones and that the volcano will be affected by eruptions and earthquakes for many thousands of years. 71 refs., 2 figs.

Geologic report for the Weldon Spring Raffinate Pits Site

International Nuclear Information System (INIS)

1984-10-01

A preliminary geologic site characterization study was conducted at the Weldon Spring Raffinate Pits Site, which is part of the Weldon Spring Site, in St. Charles County, Missouri. The Raffinate Pits Site is under the custody of the Department of Energy (DOE). Surrounding properties, including the Weldon Spring chemical plant, are under the control of the Department of the Army. The study determined the following parameters: site stratigraphy, lithology and general conditions of each stratigraphic unit, and groundwater characteristics and their relation to the geology. These parameters were used to evaluate the potential of the site to adequately store low-level radioactive wastes. The site investigation included trenching, geophysical surveying, borehole drilling and sampling, and installing observation wells and piezometers to monitor groundwater and pore pressures

A Corner-Point-Grid-Based Voxelization Method for Complex Geological Structure Model with Folds

Science.gov (United States)

Chen, Qiyu; Mariethoz, Gregoire; Liu, Gang

2017-04-01

3D voxelization is the foundation of geological property modeling, and is also an effective approach to realize the 3D visualization of the heterogeneous attributes in geological structures. The corner-point grid is a representative data model among all voxel models, and is a structured grid type that is widely applied at present. When carrying out subdivision for complex geological structure model with folds, we should fully consider its structural morphology and bedding features to make the generated voxels keep its original morphology. And on the basis of which, they can depict the detailed bedding features and the spatial heterogeneity of the internal attributes. In order to solve the shortage of the existing technologies, this work puts forward a corner-point-grid-based voxelization method for complex geological structure model with folds. We have realized the fast conversion from the 3D geological structure model to the fine voxel model according to the rule of isocline in Ramsay's fold classification. In addition, the voxel model conforms to the spatial features of folds, pinch-out and other complex geological structures, and the voxels of the laminas inside a fold accords with the result of geological sedimentation and tectonic movement. This will provide a carrier and model foundation for the subsequent attribute assignment as well as the quantitative analysis and evaluation based on the spatial voxels. Ultimately, we use examples and the contrastive analysis between the examples and the Ramsay's description of isoclines to discuss the effectiveness and advantages of the method proposed in this work when dealing with the voxelization of 3D geologic structural model with folds based on corner-point grids.

The 3D geological model of the 1963 Vajont rockslide, reconstructed with implicit surface methods

Science.gov (United States)

Bistacchi, Andrea; Massironi, Matteo; Francese, Roberto; Giorgi, Massimo; Taller, Claudio

2015-04-01

The Vajont rockslide has been the object of several studies because of its catastrophic consequences and of its particular evolution. Several qualitative or quantitative models have been presented in the last 50 years, but a complete explanation of all the relevant geological and mechanical processes remains elusive. In order to better understand the mechanics and dynamics of the 1963 event, we have reconstructed the first 3D geological model of the rockslide, which allowed us to accurately investigate the rockslide structure and kinematics. The input data for the model consisted in: pre- and post-rockslide geological maps, pre- and post-rockslide orthophotos, pre- and post-rockslide digital elevation models, structural data, boreholes, and geophysical data (2D and 3D seismics and resistivity). All these data have been integrated in a 3D geological model implemented in Gocad®, using the implicit surface modelling method. Results of the 3D geological model include the depth and geometry of the sliding surface, the volume of the two lobes of the rockslide accumulation, kinematics of the rockslide in terms of the vector field of finite displacement, and high quality meshes useful for mechanical and hydrogeological simulations. The latter can include information about the stratigraphy and internal structure of the rock masses and allow tracing the displacement of different material points in the rockslide from the pre-1963-failure to the post-rockslide state. As a general geological conclusion, we may say that the 3D model allowed us to recognize very effectively a sliding surface, whose non-planar geometry is affected by the interference pattern of two regional-scale fold systems. The rockslide is partitioned into two distinct and internally continuous rock masses with a distinct kinematics, which were characterised by a very limited internal deformation during the slide. The continuity of these two large blocks points to a very localized deformation, occurring along

Geology and paleontology of the Santa Maria district, California

Science.gov (United States)

Woodring, W.P.; Bramlette, M.N.

1950-01-01

Stratigraphy, paleontology, and geologic history.-A basement' consisting of igneous rocks of the Jurassic(?) Franciscan formation and sediments of the Upper Jurassic Knoxville formation, and formations of Tertiary and Quaternary age are exposed in the Santa Maria district. The outcrop section, exclusive of the Franciscan, has a maximum thickness of about 10,000 feet, the subsurface section about 27,000 feet. At no locality, however, is either outcrop or subsurface section as thick as the total maxima for the formations.

The Folding and Fracturing of Rocks: A milestone publication in Structural Geology research

Science.gov (United States)

Lisle, Richard; Bastida, Fernando

2017-04-01

In the field of structural geology, the textbook written by John G Ramsay in 1967, reprinted in 2004 and translated into Spanish and Chinese, is the one that has made the greatest research impact. With citations exceeding 4000 (Google Scholar) it far surpasses books by other authors on the subject, with this figure only being approached by his later book Modern Structural Geology (Ramsay and Huber 1983). In this paper we consider the factors that account for the book's success despite the fact that it is a research-level text beyond the comfort zone of most undergraduates. We also take stock of other measures of the book's success; the way it influenced the direction subsequent research effort. We summarize the major advances in structural geology that were prompted by Ramsay's book. Finally we consider the book's legacy. Before the publication of the book in 1967 structural geology had been an activity that had concentrated almost exclusively on geological mapping aimed at establishing the geometrical configuration of rock units. In fact, Ramsay himself has produced beautiful examples of such maps. However, the book made us aware that the geometrical pattern is controlled by the spatial variation of material properties, the boundary conditions, the deformation environment and the temporal variation of stresses. With the arrival of the book Structural Geology came of age as a modern scientific discipline that employed a range of tools such as those of physics, maths and engineering as well as those of geology.

ON DISCRETE STRUCTURE OF GEOLOGIC MEDIUM AND CONTINUAL APPROACH TO MODELING ITS MOVEMENTS

Directory of Open Access Journals (Sweden)

Sh. A. Mukhamediev

2016-01-01

Full Text Available This paper discusses the structure of a geologic medium represented by accessible lithified rocks and provides an overview of methods used to describe its movements. Two basic opinions are considered in the framework of the discussion: (1 an initially homogeneous and continuous geologic medium acquires the structure composed of blocks in the process of the geologic medium’s deformation/destruction/degradation, and (2 a geologic medium is composed of blocks (and often has hierarchic, active, energy-saturated features, and the continuity model is thus not valid for describing the geologic medium’s deformation. Proponents of the first point of view actively apply the standard or modified continuum model of a solid deformed body (SDB in estimations of the stress-strain state, but the input parameters of this model do not contain any information on discreteness in principle. Authors who support the second opinion, either explicitly or implicitly assume that the block structure of the geologic medium, which is detectable by geological methods, makes a direct and unambiguous impact on all other mechanical properties of the geologic medium and, above all, on the nature of its movements.Based on results obtained by interpreting the data collected in our long-term field studies of rock fracturing, mathematical processing of GPS-measurements, and theoretical models, we agree with the concept of the geologic medium’s block structure, but argue that the geologic block-structure property is not acquired but congenital. Regarding sedimentary rocks, it means that the discrete structure has been already embodied in the rock before sediment lithification, regardless of the intensity of macroscopic deformations. A discrete structure is the form of the geologic medium existence and a cause of the congenital anisotropy of the geologic medium’s strength characteristics. Due to subsequent deformation of the geologic medium, some elements of the structure can

Recent activity of the regional geologic structures in western Slovenia

Directory of Open Access Journals (Sweden)

Miloš Bavec

2007-06-01

Full Text Available Several important geological structures in the western Slovenia were identifiedas active and their activity was quantified. Geologic interpretation is based on the analysis of repeated leveling line campaigns data along the Sečovlje–Bled polygon. Taking intoaccount the limitations of the method – only the vertical component of displacement is measured – the following structures were identified as active:a juvenile syncline between Strunjan and Koper, the Kras Imbricate Structure, the Diva~a fault, the Ra{a fault, the Southalpine Front and the Julian Alps thrust. Vertical movement rate is relative, calculated with respect to the benchmark in Sečovlje. The largest uplift rate difference between Sečovlje and Bled is 7 mm/a.Vertical Geodynamic Activity (VGA is introduced as a link between geologic interpretation of geodetic measurements on one side and possible applications on the other as well as a mean of comparison between tectonically active regions.

Location of geologic structures from interpretation of ERTS-1 imagery, Carbon County, Wyoming

Science.gov (United States)

Marrs, R. W.; Barton, R.

1974-01-01

The author has identified the following significant results. Possible geologic structures in the basin sediments of Carbon County and vicinity were located by interpretation of ERTS-1 imagery. These same structures are not evident on existing conventional geologic maps of the area. Subsequent field checks confirmed much of the geologic interpretation, but revealed that two apparent closed structures identified on the ERTS-1 imagery were actually topographic pseudostructures in flat or homoclinal sediments. Stereoscopic coverage (where available) allows the interpreter to avoid such misinterpretations.

A drill-hole geodatabase as a tool to investigate geological hazard in Napoli Urban Area

Science.gov (United States)

Albericoa, I.; Lirer, L.; Petrosino, P.

2003-04-01

Geological investigations in urban areas are complicated by the absence of good outcrops and field exposures, as a result of the density of civil buildings and railway and road network. On the other side, in urban areas geological investigation represents a basic tool to decisional support for the management of present private buildings and public works and for the planning of new ones. This is much more true in urban areas very exposed to geological hazard (volcanic, hydrogeological, seismic) where the high exposed value greatly rises the risk. The methodology to deal with the geological hazard in urban areas here presented is the reconstruction of buried geological formations deduced by drill-holes stratigraphy.The test area is represented by the whole municipality of Napoli city, that proves very apt to the investigation of the hazard in urban areas since it stands over an active volcanic area, comprised between the Campi Flegrei volcanic field and the Somma-Vesuvio district, that both gave explosive and effusive activity through the last centuries. Besides, the extension of the main part of the city constrained between the coastline and the belt of volcanic hills together with the presence of loose material due to pyroclastic activity makes the alluvional events an other hazardous phenomenon for the city. The performed up datable drill-holes geodata-base for the city of Napoli at present contains the record of about 800 holes stratigraphy, collected through the main public and private bodies, reflecting the drill-holes surveys made along the last 50 years before constructing the main railways, roads and aqueduct network. Drill-holes data have been interpreted and can now be read under various viewpoints (geological, lithological, volcanological); the present work presents the first results of the geological hazard investigation. The investigation of buried stratigraphy in the eastern area allows to identify the presence of pyroclastic flow deposits from Somma

Geologic and hydrologic research at the Western New York Nuclear Service Center, West Valley, New York. Final report, August 1982-December 1983

International Nuclear Information System (INIS)

Albanese, J.R.; Anderson, S.L.; Fakundiny, R.H.; Potter, S.M.; Rogers, W.B.; Whitbeck, L.F.; LaFleur, R.G.; Boothroyd, J.C.; Timson, B.S.

1984-06-01

This report is the last in a series by the New York State Geological Survey on studies funded by the US Nuclear Regulatory Commission. The report covers five important aspects of the geology and hydrology of the Western New York Nuclear Service Center, near West Valley, New York: geomorphology, stratigraphy, sedimentology, surface water, and radionuclide analyses. We reviewed past research on these subjects and present new data obtained in the final phase of NYSGS research at the site. Also presented are up-to-date summaries of the present knowledge of geomorphology and stratigraphy. The report contains a significant bibliography of previous West Valley studies. Appendices include a report on the Fall 1983 Drilling Project and the procedures used, history and prognosis of Cattaraugus Creek and tributaries down cutting, and bar modification and landslide processes of Buttermilk Valley. 100 references, 7 figures, 7 tables

Determination of subsurface geological structure with borehole gravimetry

International Nuclear Information System (INIS)

Clark, S.R.; Hearst, J.R.

1983-07-01

Conventional gamma-gamma and gravimetric density measurements are routinely gathered for most holes used for underground nuclear tests. The logs serve to determine the subsurface structural geology near the borehole. The gamma-gamma density log measures density of the rock within about 15 cm of the borehole wall. The difference in gravity measured at two depths in a borehole can be interpreted in terms of the density of an infinite, homogeneous, horizontal bed between those depths. When the gravimetric density matches the gamma-gamma density over a given interval it is assumed that the bed actualy exists, and that rocks far from the hole must be the same as those encountered adjacent to the borehole. Conversely, when the gravimetric density differs from the gamma-gamma density it is apparent that the gravimeter is being influenced by a rock mass of different density than that at the hole wall. This mismatch can be a powerful tool to deduce the local structural geology. The geology deduced from gravity mesurements in emplacement hole, U4al, and the associated exploratory hole, UE4al, is an excellent example of the power of the method

3D mechanical stratigraphy of a deformed multi-layer: Linking sedimentary architecture and strain partitioning

Science.gov (United States)

Cawood, Adam J.; Bond, Clare E.

2018-01-01

Stratigraphic influence on structural style and strain distribution in deformed sedimentary sequences is well established, in models of 2D mechanical stratigraphy. In this study we attempt to refine existing models of stratigraphic-structure interaction by examining outcrop scale 3D variations in sedimentary architecture and the effects on subsequent deformation. At Monkstone Point, Pembrokeshire, SW Wales, digital mapping and virtual scanline data from a high resolution virtual outcrop have been combined with field observations, sedimentary logs and thin section analysis. Results show that significant variation in strain partitioning is controlled by changes, at a scale of tens of metres, in sedimentary architecture within Upper Carboniferous fluvio-deltaic deposits. Coupled vs uncoupled deformation of the sequence is defined by the composition and lateral continuity of mechanical units and unit interfaces. Where the sedimentary sequence is characterized by gradational changes in composition and grain size, we find that deformation structures are best characterized by patterns of distributed strain. In contrast, distinct compositional changes vertically and in laterally equivalent deposits results in highly partitioned deformation and strain. The mechanical stratigraphy of the study area is inherently 3D in nature, due to lateral and vertical compositional variability. Consideration should be given to 3D variations in mechanical stratigraphy, such as those outlined here, when predicting subsurface deformation in multi-layers.

A 3D geological and geomechanical model of the 1963 Vajont landslide

Science.gov (United States)

Bistacchi, Andrea; Massironi, Matteo; Francese, Roberto; Giorgi, Massimo; Chistolini, Filippo; Battista Crosta, Giovanni; Castellanza, Riccardo; Frattini, Paolo; Agliardi, Federico; Frigerio, Gabriele

2014-05-01

The Vajont rockslide has been the object of several studies because of its catastrophic consequences and particular evolution. Several qualitative or quantitative models have been presented in the last 50 years, but a complete explanation of all relevant geological and mechanical processes remains elusive. In order to better understand the mechanics and dynamics of the 1963 event, we have reconstructed the first 3D geological model of the rockslide, which allowed us to accurately investigate the rockslide structure and kinematics. The input data for the model consisted in: pre- and post-rockslide geological maps, pre- and post-rockslide orthophotos, pre- and post-rockslide digital elevation models, structural data, boreholes, and geophysical data (2D and 3D seismics and resistivity). All these data have been integrated in a 3D geological model implemented in Gocad®, using the implicit surface modelling method. Results of the 3D geological model include the depth and geometry of the sliding surface, the volume of the two lobes of the rockslide accumulation, kinematics of the rockslide in terms of the vector field of finite displacement, and high quality meshes useful for mechanical and hydrogeological simulations. The latter can include information about the stratigraphy and internal structure of the rock masses and allow tracing the displacement of different material points in the rockslide from the pre-1963-failure to the post-rockslide state. As a general geological conclusion, we may say that the 3D model allowed us to recognize very effectively a sliding surface, whose non-planar geometry is affected by the interference pattern of two regional-scale fold systems. The rockslide is partitioned into two distinct and internally continuous rock masses with a distinct kinematics, which were characterised by a very limited internal deformation during the slide. The continuity of these two large blocks points to a very localized deformation, occurring along a thin

The Stratigraphy and Evolution of the Lunar Crust

Science.gov (United States)

McCallum, I. Stewart

1998-01-01

Reconstruction of stratigraphic relationships in the ancient lunar crust has proved to be a formidable task. The intense bombardment during the first 700 m.y. of lunar history has severely perturbed the original stratigraphy and destroyed the primary textures of all but a few nonmare rocks. However, a knowledge of the crustal stratigraphy as it existed prior to the cataclysmic bombardment about 3.9 Ga is essential to test the major models proposed for crustal origin, i.e., crystal fractionation in a global magmasphere or serial magmatism in a large number of smaller bodies. Despite the large difference in scale implicit in these two models, both require an efficient separation of plagioclase and mafic minerals to form the anorthositic crust and the mafic mantle. Despite the havoc wreaked by the large body impactors, these same impact processes have brought to the lunar surface crystalline samples derived from at least the upper half of the lunar crust, thereby providing an opportunity to reconstruct the stratigraphy in areas sampled by the Apollo missions. As noted, ejecta from the large multiring basins are dominantly, or even exclusively, of crustal origin. Given the most recent determinations of crustal thicknesses, this implies an upper limit to the depth of excavation of about 60 km. Of all the lunar samples studied, a small set has been recognized as "pristine", and within this pristine group, a small fraction have retained some vestiges of primary features formed during the earliest stages of crystallization or recrystallization prior to 4.0 Ga. We have examined a number of these samples that have retained some record of primary crystallization to deduce thermal histories from an analysis of structural, textural, and compositional features in minerals from these samples. Specifically, by quantitative modeling of (1) the growth rate and development of compositional profiles of exsolution lamellae in pyroxenes and (2) the rate of Fe-Mg ordering in

Geological Geophysical and structural studies in Mina Ratones (Pluton de Albala)

International Nuclear Information System (INIS)

Perez-Estaun, A.; Carbonell, R.; Marti, D.; Flecha, I.; Escuder Viruete, J.

2002-01-01

Mina Ratones environmental restoration project included petrological, structural,geophysical, hydrogeological and hydrogeochemical studies. The main objective of the geologic-structural and geophysical studies was the Albala granite structural characterization around the Mina Ratones uranium mine. The location of facies, fault zones (faults and dykes) as well as the distribution of some physical properties inside the rock massif was obtained for a granitic black of 900, 500, and 500 m. The geologic-structural and geophysical techniques applied to Mina Ratones provided a multidisciplinary approach for high resolution characterization of rock massif, and the structures potentially containing fluids,able to be applied to the hydrogeological modelling to a particular area. Geological studies included a detailed structural mapping of the area surrounding the mine (1:5,000 scale), the geometric, kinematics, and dynamics analysis of fractures of all scales, the petrology and geochemistry of fault rocks and altered areas surrounding fractures, and the microstructural studies of samples from surface and core lags. The construction of geostatistical models in two and three dimensions had helped to characterize the Mina Ratones rock massif showing the spatial distribution of fault zones, fracture intensity, granite composition heterogeneities, fluid-rock interaction zones, and physical properties. (Author)

Groundwater arsenic contamination affecting different geologic domains in India--a review: influence of geological setting, fluvial geomorphology and Quaternary stratigraphy.

Science.gov (United States)

Acharyya, Subhrangsu K; Shah, Babar A

2007-10-01

Arsenic contamination in groundwater is pervasive within lowland organic-rich Bengal Delta and narrow entrenched channels in the Middle Ganga floodplains. Local areas of Damodar fan-delta and isolated areas within the Dongargarh Proterozoic rift-zone in central India are also contaminated. In this rift-zone, arsenic is enriched in felsic magmatic rocks and weathered rocks and soils from local areas are enriched further in arsenic and iron. Late Quaternary stratigraphy, geomorphology and sedimentation have influenced groundwater arsenic contamination in alluvium that aggraded during the Holocene sea-level rise. No specific source of arsenic could be identified, although Himalaya is the main provenance for the Ganga floodplain and the Bengal Delta. Gondwana coal seams and other Peninsular Indian rocks might be sources for arsenic in the Damodar fan-delta. As-bearing pyrite or any As-mineral is nearly absent in the aquifer sediments. Arsenic mainly occurs adsorbed on hydrated-iron-oxide (HFO), which coat sediment grains and minerals. Arsenic and iron are released to groundwater by bio-mediated reductive dissolution of HFO with corresponding oxidation of organic matter.

SITE-94. Development of a geological and a structural model of Aespoe, southeastern Sweden

International Nuclear Information System (INIS)

Tiren, S.A.; Beckholmen, M.; Askling, P.; Voss, C.

1996-12-01

The objective of the present study is to construct three-dimensional geological and structural models to be used within the SKI SITE-94 project as a base for modelling hydrogeological, hydrochemical, and rock mechanical bedrock conditions, mass transport and layout of a hypothetical repository. The basic input data in the SITE-94 geological and structural models are restricted to geological and structural readings and geophysical measurements made prior to building the Hard Rock Laboratory. 114 refs, 82 figs, 28 tabs

Application of sequence stratigraphy to carbonate reservoir prediction, Early Palaeozoic eastern Warburton basin, South Australia

Energy Technology Data Exchange (ETDEWEB)

Xiaowen S.; Stuart, W.J.

1996-12-31

The Early Palaeozoic Warburton Basin underlies the gas and oil producing Cooper and Eromanga Basins. Postdepositional tectonism created high potential fracture porosities, complicating the stratigraphy and making reservoir prediction difficult. Sequence stratigraphy integrating core, cuttings, well-log, seismic and biostratigraphic data has recognized a carbonate-dominated to mixed carbonate/siliciclastic supersequence comprising several depositional sequences. Biostratigraphy based on trilobites and conodonts ensures reliable well and seismic correlations across structurally complex areas. Lithofacies interpretation indicates sedimentary environments ranging from carbonate inner shelf, peritidal, shelf edge, deep outer shelf and slope to basin. Log facies show gradually upward shallowing trends or abrupt changes indicating possible sequence boundaries. With essential depositional models and sequence analysis from well data, seismic facies suggest general reflection configurations including parallel-continuous layered patterns indicating uniform neuritic shelf, and mounded structures suggesting carbonate build-ups and pre-existing volcanic relief. Seismic stratigraphy also reveals inclined slope and onlapping margins of a possibly isolated platform geometry. The potential reservoirs are dolomitized carbonates containing oomoldic, vuggy, intercrystalline and fracture porosities in lowstand systems tracts either on carbonate mounds and shelf crests or below shelf edge. The source rock is a deep basinal argillaceous mudstone, and the seal is fine-grained siltstone/shale of the transgressive system tract.

Application of sequence stratigraphy to carbonate reservoir prediction, Early Palaeozoic eastern Warburton basin, South Australia

Energy Technology Data Exchange (ETDEWEB)

Xiaowen S.; Stuart, W.J.

1996-01-01

The Early Palaeozoic Warburton Basin underlies the gas and oil producing Cooper and Eromanga Basins. Postdepositional tectonism created high potential fracture porosities, complicating the stratigraphy and making reservoir prediction difficult. Sequence stratigraphy integrating core, cuttings, well-log, seismic and biostratigraphic data has recognized a carbonate-dominated to mixed carbonate/siliciclastic supersequence comprising several depositional sequences. Biostratigraphy based on trilobites and conodonts ensures reliable well and seismic correlations across structurally complex areas. Lithofacies interpretation indicates sedimentary environments ranging from carbonate inner shelf, peritidal, shelf edge, deep outer shelf and slope to basin. Log facies show gradually upward shallowing trends or abrupt changes indicating possible sequence boundaries. With essential depositional models and sequence analysis from well data, seismic facies suggest general reflection configurations including parallel-continuous layered patterns indicating uniform neuritic shelf, and mounded structures suggesting carbonate build-ups and pre-existing volcanic relief. Seismic stratigraphy also reveals inclined slope and onlapping margins of a possibly isolated platform geometry. The potential reservoirs are dolomitized carbonates containing oomoldic, vuggy, intercrystalline and fracture porosities in lowstand systems tracts either on carbonate mounds and shelf crests or below shelf edge. The source rock is a deep basinal argillaceous mudstone, and the seal is fine-grained siltstone/shale of the transgressive system tract.

Structural geology practice and learning, from the perspective of cognitive science

Science.gov (United States)

Shipley, Thomas F.; Tikoff, Basil; Ormand, Carol; Manduca, Cathy

2013-09-01

Spatial ability is required by practitioners and students of structural geology and so, considering spatial skills in the context of cognitive science has the potential to improve structural geology teaching and practice. Spatial thinking skills may be organized using three dichotomies, which can be linked to structural geology practice. First, a distinction is made between separating (attending to part of a whole) and combining (linking together aspects of the whole). While everyone has a basic ability to separate and combine, experts attend to differences guided by experiences of rock properties in context. Second, a distinction is made between seeing the relations among multiple objects as separate items or the relations within a single object with multiple parts. Experts can flexibly consider relations among or between objects to optimally reason about different types of spatial problems. Third, a distinction is made between reasoning about stationary and moving objects. Experts recognize static configurations that encode a movement history, and create mental models of the processes that led to the static state. The observations and inferences made by a geologist leading a field trip are compared with the corresponding observations and inferences made by a cognitive psychologist interested in spatial learning. The presented framework provides a vocabulary for discussing spatial skills both within and between the fields of structural geology and cognitive psychology.

Upper Neogene stratigraphy and tectonics of Death Valley — a review

Science.gov (United States)

Knott, J. R.; Sarna-Wojcicki, A. M.; Machette, M. N.; Klinger, R. E.

2005-12-01

New tephrochronologic, soil-stratigraphic and radiometric-dating studies over the last 10 years have generated a robust numerical stratigraphy for Upper Neogene sedimentary deposits throughout Death Valley. Critical to this improved stratigraphy are correlated or radiometrically-dated tephra beds and tuffs that range in age from > 3.58 Ma to Mormon Point. This new geochronology also establishes maximum and minimum ages for Quaternary alluvial fans and Lake Manly deposits. Facies associated with the tephra beds show that ˜3.3 Ma the Furnace Creek basin was a northwest-southeast-trending lake flanked by alluvial fans. This paleolake extended from the Furnace Creek to Ubehebe. Based on the new stratigraphy, the Death Valley fault system can be divided into four main fault zones: the dextral, Quaternary-age Northern Death Valley fault zone; the dextral, pre-Quaternary Furnace Creek fault zone; the oblique-normal Black Mountains fault zone; and the dextral Southern Death Valley fault zone. Post - 3.3 Ma geometric, structural, and kinematic changes in the Black Mountains and Towne Pass fault zones led to the break up of Furnace Creek basin and uplift of the Copper Canyon and Nova basins. Internal kinematics of northern Death Valley are interpreted as either rotation of blocks or normal slip along the northeast-southwest-trending Towne Pass and Tin Mountain fault zones within the Eastern California shear zone.

Analysis of effects of geological structures in rock driving by TBM

Directory of Open Access Journals (Sweden)

Ľudmila Tréfová

2006-12-01

Full Text Available Although mechanical properties belongs to important parameter for the excavation modelling, effect of geological structures on the rock massive fragmentation is often much higher than varying rock properties. This paper deals with the analysis of geological structures. It is focused on the schistosity orientation towards the tunnel azimuth. The aim is to define of schistosity effect on the penetration rate. It is a basis creating of fuzzy rules for the performance model full-profile tunnel boring machine

Bedrock geologic Map of the Central Block Area, Yucca Mountain, Nye County, Nevada

International Nuclear Information System (INIS)

W.C. Day; C. Potter; D. Sweetkind; R.P. Dickerson; C.A. San Juan

1998-01-01

Bedrock geologic maps form the foundation for investigations that characterize and assess the viability of the potential high-level radioactive waste repository at Yucca Mountain, Nevada. As such, this map focuses on the central block at Yucca Mountain, which contains the potential repository site. The central block is a structural block of Tertiary volcanic rocks bound on the west by the Solitario Canyon Fault, on the east by the Bow Ridge Fault, to the north by the northwest-striking Drill Hole Wash Fault, and on the south by Abandoned Wash. Earlier reconnaissance mapping by Lipman and McKay (1965) provided an overview of the structural setting of Yucca Mountain and formed the foundation for selecting Yucca Mountain as a site for further investigation. They delineated the main block-bounding faults and some of the intrablock faults and outlined the zoned compositional nature of the tuff units that underlie Yucca Mountain. Scott and Bonk (1984) provided a detailed reconnaissance geologic map of favorable area at Yucca Mountain in which to conduct further site-characterization studies. Of their many contributions, they presented a detailed stratigraphy for the volcanic units, defined several other block-bounding faults, and outlined numerous intrablock faults. This study was funded by the U.S. Department of Energy Yucca Mountain Project to provide a detailed (1:6,000-scale) bedrock geologic map for the area within and adjacent to the potential repository area at Yucca Mountain, Nye County, Nevada. Prior to this study, the 1:12,000-scale map of Scott and Bonk (1984) was the primary source of bedrock geologic data for the Yucca Mountain Project. However, targeted detailed mapping within the central block at Yucca Mountain revealed structural complexities along some of the intrablock faults that were not evident at 1:12,000 (Scott and Bonk, 1984). As a result, this study was undertaken to define the character and extent of the dominant structural features in the

Preliminary geologic map of the Black Mountain area northeast of Victorville, San Bernardino County, California

Science.gov (United States)

Stone, Paul

2006-01-01

The Black Mountain area is in the Mojave Desert about 20 km northeast of Victorville, California. The geology of this area is of interest primarily for its excellent exposures of the early Mesozoic Fairview Valley Formation, a sequence of weakly metamorphosed sedimentary rocks including a thick, commercially important unit of limestone conglomerate that has been mined for cement at Black Mountain Quarry for several decades. Recent geochronologic work has shown that the Fairview Valley Formation is probably of Early Jurassic age. This preliminary geologic map of the Black Mountain area depicts the stratigraphic and structural relations of the Fairview Valley Formation and the associated rocks, most notably the overlying Sidewinder Volcanics of Early(?), Middle, and Late(?) Jurassic age. The map is based on new field studies by the author designed to clarify details of the stratigraphy and structure unresolved by previous investigations. The map is considered preliminary because the ages of some geologic units critical for a satisfactory understanding of the stratigraphic and structural framework remain unknown. The map area also includes a segment of the Helendale Fault, one of several faults of known or inferred late Cenozoic right-lateral displacement that make up the Eastern California Shear Zone. The fault is marked by aligned northeast-facing scarps in Pleistocene or older alluvial deposits and the underlying bedrock units. Relations in the map area suggest that right-lateral displacement on the Helendale Fault probably does not exceed 2 km, a conclusion compatible with previous estimates of displacement on this fault based on relations both within and outside the Black Mountain area.

Geologic evaluation of the Oasis Valley basin, Nye County, Nevada

Energy Technology Data Exchange (ETDEWEB)

Fridrich, C.J.; Minor, S.A.; and Mankinen, E.A.

2000-01-13

This report documents the results of a geologic study of the area between the underground-nuclear-explosion testing areas on Pahute Mesa, in the northwesternmost part of the Nevada Test Site, and the springs in Oasis Valley, to the west of the Test Site. The new field data described in this report are also presented in a geologic map that is a companion product(Fridrich and others, 1999) and that covers nine 7.5-minute quadrangles centered on Thirsty Canyon SW, the quadrangle in which most of the Oasis Valley springs are located. At the beginning of this study, published detailed maps were available for 3 of the 9 quadrangles of the study area: namely Thirsty Canyon (O'Connor and others, 1966); Beatty (Maldonado and Hausback, 1990); and Thirsty Canyon SE (Lipman and others, 1966). Maps of the last two of these quadrangles, however, required extensive updating owing to recent advances in understanding of the regional structure and stratigraphy. The new map data are integrated in this re port with new geophysical data for the Oasis Valley area, include gravity, aeromagnetic, and paleomagnetic data (Grauch and others, 1997; written comm., 1999; Mankinen and others, 1999; Hildenbrand and others, 1999; Hudson and others, 1994; Hudson, unpub. data).

Geologic map of the northwest quarter of the Bullfrog 15-minute quadrangle, Nye County, Nevada

International Nuclear Information System (INIS)

Maldonado, F.

1990-01-01

This study of the northwest quarter of the Bullfrog 15-minute quadrangle was undertaken to determine the stratigraphy and structural setting as part of a regional study in cooperation with the US Department of Energy. Geologic data were plotted on aerial photographs at a scale of 1:24,000. Alluvial deposits were mapped on aerial photographs, and, in some cases, field-checked. Thickness of bedded tuff as shown on the map and in the geologic sections was exaggerated in some cases in order to show distribution. Thicknesses of units are approximate due to varying degrees of internal deformation. A detachment fault is defined for this study as ''...a low-angle normal fault that formed at a low angle, has significant displacement, and is of subregional extent.'' Nomenclature for lavas and igneous dikes is based on field identifications, guided by some petrographic determinations; latite-type rocks are termed ''latitic, '' dacite-type, ''dacitic,'' and so forth. Age determinations where indicated for the rock units have been corrected for new K-Ar constants. 17 refs

A Subsurface Soil Composition and Physical Properties Experiment to Address Mars Regolith Stratigraphy

Science.gov (United States)

Richter, L.; Sims, M.; Economou, T.; Stoker, C.; Wright, I.; Tokano, T.

2004-01-01

Previous in-situ measurements of soil-like materials on the surface of Mars, in particular during the on-going Mars Exploration Rover missions, have shown complex relationships between composition, exposure to the surface environment, texture, and local rocks. In particular, a diversity in both compositional and physical properties could be established that is interpreted to be diagnostic of the complex geologic history of the martian surface layer. Physical and chemical properties vary laterally and vertically, providing insight into the composition of rocks from which soils derive, and environmental conditions that led to soil formation. They are central to understanding whether habitable environments existed on Mars in the distant past. An instrument the Mole for Soil Compositional Studies and Sampling (MOCSS) - is proposed to allow repeated access to subsurface regolith on Mars to depths of up to 1.5 meters for in-situ measurements of elemental composition and of physical and thermophysical properties, as well as for subsurface sample acquisition. MOCSS is based on the compact PLUTO (PLanetary Underground TOol) Mole system developed for the Beagle 2 lander and incorporates a small X-ray fluorescence spectrometer within the Mole which is a new development. Overall MOCSS mass is approximately 1.4 kilograms. Taken together, the MOCSS science data support to decipher the geologic history at the landing site as compositional and textural stratigraphy if they exist - can be detected at a number of places if the MOCSS were accommodated on a rover such as MSL. Based on uncovered stratigraphy, the regional sequence of depositional and erosional styles can be constrained which has an impact on understanding the ancient history of the Martian near-surface layer, considering estimates of Mars soil production rates of 0.5... 1.0 meters per billion years on the one hand and Mole subsurface access capability of approximately 1.5 meters. An overview of the MOCSS, XRS

Stratigraphy of the Descartes region /Apollo 16/ - Implications for the origin of samples

Science.gov (United States)

Head, J. W.

1974-01-01

Analysis of terrain in the Apollo 16 Descartes landing region shows a series of features that form a stratigraphic sequence which dominates the history and petrogenesis at the site. An ancient 150-km diam crater centered on the Apollo 16 site is one of the earliest recognizable major structures. Nectaris ejecta was concentrated in a regional low at the base of the back slope of the Nectaris basin to form the Descartes Mountains. Subsequently, a 60-km diam crater formed in the Descartes Mountains centered about 25 km to the west of the site. This crater dominates the geology and petrogenetic history of the site. Stone and Smoky Mountains represent the degraded terraced crater walls, and the dark matrix breccias and metaclastic rocks derived from North and South Ray craters represent floor fallback breccias from this cratering event. The interpretation is developed that the stratigraphy of the Cayley and Descartes, and thus the historical record of the Apollo 16 region, documents the complex interaction of deposits and morphology of local and regional impact cratering events. Large local 60- to 150-km diam craters have had a dramatic and previously unrecognized effect on the history and petrology of the Apollo 16 site.

Application status and vistas of sequence stratigraphy to the exploration of sandstone-hosted uranium deposits

International Nuclear Information System (INIS)

Guo Qingyin; Chen Zuyi; Yu Jinshui; Han Shuqin

2008-01-01

Sequence stratigraphy is a newly developed subject based on seismostratigraphy, and has been widely applied in the exploration of hydrocarbon and other sedimentogenic mineral deposits and great achievements have been obtained. However, the application of sequence stratigraphy to the exploration of sandstone-hosted uranium deposits is just at the beginning. In this paper, some primary research achievements of sequence stratigraphy to the exploration of sandstone-hosted uranium deposits are summarized, and problems and their reasons of the application of sequence stratigraphy are discussed. Further more, according to characteristics of sandstone-hosted uranium deposits and the development of sequence stratigraphy, the application vistas of sequence stratigraphy to the exploration of sandstone-hosted uranium deposits are estimated. Finally, application directions are proposed, and some specific suggestions are given. (authors)

Identifying Students' Conceptions of Basic Principles in Sequence Stratigraphy

Science.gov (United States)

Herrera, Juan S.; Riggs, Eric M.

2013-01-01

Sequence stratigraphy is a major research subject in the geosciences academia and the oil industry. However, the geoscience education literature addressing students' understanding of the basic concepts of sequence stratigraphy is relatively thin, and the topic has not been well explored. We conducted an assessment of 27 students' conceptions of…

Geological Structure and Radon Hazards in Lublin Region

Directory of Open Access Journals (Sweden)

Lucjan Gazda

2018-03-01

Full Text Available The purpose of the study was to show the relationship between the geological structure of the Lublin region (eastern Poland and radon concentrations in the ground air, and therefore, in the indoor environment of buildings located in that area. The study was based on the information pertaining to the geological structure of Lublin region available in the literature. The radon concentrations in buildings, caves, wells, as well as coal, phosphate and chalk mines were measured with both passive and active methods. Elemental analyses and uranium and lead isotope analyses of ground rocks were also performed. The conducted studies indicated that the sources of radon in Lublin region constitute Paleogene and Mesozoic sedimentary rocks rich in radionuclides. Application of radon remediation methods is recommended in the existing buildings located in the vicinity of these rocks, which are characterized by relatively high radon exhalations. On the other hand, the designed buildings should employ the measures protecting against harmful effects of radon presence.

A stratigraphy fieldtrip for people with visual impairment

Science.gov (United States)

Gomez-Heras, Miguel; Gonzalez-Acebron, Laura; Muñoz-Garcia, Belen; Garcia-Frank, Alejandra; Fesharaki, Omid

2017-04-01

This communication presents how a stratigraphy fieldtrip adapted to people with visual impairment was prepared and carried out. This fieldtrip aimed to promote scientific knowledge on Earth sciences to people with visual impairment and to inspire Earth scientists to take into account the needs of people with disabilities when designing public engagement activities. To do this, the theme chosen for the fieldtrip was the importance of sedimentary rocks shaping the Earth and what information can one extract from observing sedimentary structures. The Triassic outcrops of Riba de Santiuste (Guadalajara, Spain) were observed during this fieldtrip. The expected learning outcomes were: a) understanding what are sedimentary rocks, how they are formed and how they fold and crop out, b) knowing what is a sedimentary structure and recognising some of them and c) be able to make inferences of the sedimentary environment from certain sedimentary structures. The fieldtrip was prepared, through the NGO "Science without Barriers" together with the Madrid delegation of the National Association for Spanish Blind People (ONCE-Madrid). ONCE-Madrid was responsible of advertising this activity as a part of their yearly cultural program to its affiliate. A preparatory fieldtrip was carried out to test the teaching methodology and to make an appropriate risk assessment. This was made together with the responsible of the Culture Area of ONCE-Madrid and two blind people. The involvement of end-users in the preparation of activities is in the core of the European Disability Forum motto: "Nothing about us without us". A crucial aspect of the site was accessibility. In terms of perambulatory accessibility of outcrops the site is excellent and suitable to some extent for end-users regardless of their physical fitness. The fieldtrip itself took place on October 15th 2016 and 30 people with and without visual disability attended. In addition to overall observations and explanations of strata and

Preliminary hydrogeological evaluation of geological units from the Mesa de los Santos, Santander

International Nuclear Information System (INIS)

Diaz, Eliana Jimena; Contreras, Nathalia Maria; Pinto, Jorge Eduardo; Velandia, Francisco; Morales, Carlos Julio; Hincapie, Gloria

2009-01-01

This paper present a preliminary hydrogeological evaluation of La Mesa de Los Santos' lithostratigraphic formations, based on the geological mapping, stratigraphy and inventory of water points. All this is supplemented with the analysis of primary porosity by means of the petrographic study and the secondary porosity related statistically with the quantity of fractures of each formation, as well as opening, interconnection and dip. It is made an approach to hydrogeological potential of the geologic outcropping formations in La Mesa de Los Santos, Department of Santander, from the stratigraphic and petrographic analysis and the structural features of these formations. The Upper Member of Los Santos Formation presents the highest potential because of rock's fracturing, continued by the Lower Member with low primary porosity and half fracturing. Silgara Formation, Granito de Pescadero, Jordan Formation and some sections of the sandy levels of the Rosablanca Formation presents a lowest potential due to its low porosity and low grade of fracturing. Low permeability is presented in the Middle Member of the Los Santos Formation, Paja and Tablazo formations, as well as in sectors of the fore mentioned formations and in the Quaternary deposits.

Structural geologic study of southeastern Missouri

International Nuclear Information System (INIS)

Satterfield, I.R.; Ward, R.A.

1978-01-01

A geologic map at 1:62,500 scale was prepared of the Cretaceous (Mesozoic) and Tertiary (cenozoic) sediments and seven major units were recognized with emphasis on faulting. Faulted sediments of Pliocene age (possibly Pleistocene) were observed and younger units are suspected to be involved. Data from hand-augered holes plus water well data were logged and plotted. The feasibility of using physical data (size analysis and pH) as a correlation tool for determining structural disturbance in loess deposits was established

Geologic studies in Alaska by the U.S. Geological Survey, 1992

Science.gov (United States)

Dusel-Bacon, Cynthia; Till, Alison B.

1993-01-01

This collection of 19 papers continues the annual series of U.S. Geological Survey reports on the geology of Alaska. The contributions, which include full-length Articles and shorter Geologic Notes, cover a broad range of topics including dune formation, stratigraphy, paleontology, isotopic dating, mineral resources, and tectonics. Articles, grouped under four regional headings, span nearly the entire State from the North Slope to southwestern, south-central, and southeastern Alaska (fig. 1).In the section on northern Alaska, Galloway and Carter use new data on dune morphology and radiocarbon ages from the western Arctic Coastal Plain to develop a late Holocene chronology of multiple episodes of dune stabilization and reactivation for the region. Their study has important implications for climatic changes in northern Alaska during the past 4,000 years. In two papers, Dumoulin and her coauthors describe lithofacies and conodont faunas of Carboniferous strata in the western Brooks Range, discuss depositional environments, and propose possible correlations and source areas for some of the strata. Schenk and Bird propose a preliminary division of the Lower Cretaceous stratigraphic section in the central part of the North Slope into depositional sequences. Aleinikoff and others present new U-Pb data for zircons from metaigneous rocks from the central Brooks Range. Karl and Mull, reacting to a proposal regarding terrane nomenclature for northern Alaska that was published in last year's Alaskan Studies Bulletin, provide a historical perspective of the evolution of terminology for tectonic units in the Brooks Range and present their own recommendations.

Geologic report of the Maquoketa Shale, New Albany Shale, and Borden Group rocks in the Illinois Basin as potential solid waste repository sites

International Nuclear Information System (INIS)

Droste, J.B.; Vitaliano, C.J.

1976-06-01

We have evaluated the Illinois Basin in order to select a ''target site'' for a possible solid nuclear waste repository. In the process we have been mindful of geology (particularly stratigraphy and lithology and structure), terrane, population density, land use, land ownership and accessibility. After taking these restrictions into account, we have singled out a strip of land in south central Indiana in which we have selected four potential sites worthy of further exploration. In three of the sites the geology, lithology, and depth below the surface are more than adequate for crypt purposes in two separate formations--the Maquoketa Shale of the Ordovician System and the New Albany Shale-Borden Group of the Upper Devonian-Mississippian Systems. The interval between the two is several hundred feet. The geology and associated features in the fourth site are undoubtedly similar to those in the first three. In all four selections a sizeable proportion of the land is in public ownership and the population density in the nonpublicly owned land is low. The geology, lithology, and position of the target formations have been projected into the sites in question from data provided by drill core records of the Indiana Geological Survey. Precise details would, of course, require exploratory drilling on the selected site

Study on the Geological Structure around KURT Using a Deep Borehole Investigation

International Nuclear Information System (INIS)

Park, Kyung Woo; Kim, Kyung Su; Koh, Yong Kwon; Choi, Jong Won

2010-01-01

To characterize geological features in study area for high-level radioactive waste disposal research, KAERI (Korea Atomic Energy Research Institute) has been performing the several geological investigations such as geophysical surveys and borehole drilling since 1997. Especially, the KURT (KAERI Underground Research Tunnel) constructed to understand the deep geological environments in 2006. Recently, the deep borehole of 500 m depths was drilled to confirm and validate the geological model at the left research module of the KURT. The objective of this research was to identify the geological structures around KURT using the data obtained from the deep borehole investigation. To achieve the purpose, several geological investigations such as geophysical and borehole fracture surveys were carried out simultaneously. As a result, 7 fracture zones were identified in deep borehole located in the KURT. As one of important parts of site characterization on KURT area, the results will be used to revise the geological model of the study area

Kriging for interpolation of sparse and irregularly distributed geologic data

Energy Technology Data Exchange (ETDEWEB)

Campbell, K.

1986-12-31

For many geologic problems, subsurface observations are available only from a small number of irregularly distributed locations, for example from a handful of drill holes in the region of interest. These observations will be interpolated one way or another, for example by hand-drawn stratigraphic cross-sections, by trend-fitting techniques, or by simple averaging which ignores spatial correlation. In this paper we consider an interpolation technique for such situations which provides, in addition to point estimates, the error estimates which are lacking from other ad hoc methods. The proposed estimator is like a kriging estimator in form, but because direct estimation of the spatial covariance function is not possible the parameters of the estimator are selected by cross-validation. Its use in estimating subsurface stratigraphy at a candidate site for geologic waste repository provides an example.

Appendix Q: siting considerations for submarine geologic disposal of nuclear waste

International Nuclear Information System (INIS)

Hollister, C.D.; Corliss, B.H.

1981-01-01

Site suitability characteristics of submarine geological formations for the disposal of radioactive wastes include the distribution coefficient of the host medium, permeability, viscoelastic nature of the sediments, influence of organic material on remobilization, and effects of thermal stress. The submarine geological formation that appears to best satisfy these criteria is abyssal red clay. Regions in the ocean that have coarse grained deposits, high or variable thermal conductivity, high organic carbon content, and sediment thickness of less than 50 m are not being considered at this time. The optimum geological environment should be tranquil and have environmental predictability over a minimum of 10 5 years. A paleoenvironmental model of Cenozoic sedimentation in the central North Pacific has been constructed from sedimentological, geotechnical and stratigraphic data derived from a single giant piston core collected in the central North Pacific (GPC-3: 30 0 N, 157 0 W; 5705 m). This core represents a record of nearly continuous sedimentation for nearly 70 million years. The core was taken from a region of abyssal hill topography located beneath the present-day carbonate compensation depth. It contains 24.5 meters of undisturbed sediment composed of oxidized brown clay with altered ash layers. Paleomagnetic stratigraphy for the upper 4.5 meters indicates sedimentation rates are 2.5 mm/1000 years for the last 2 m.y. and 1.1 mm/1000 years before that to 2.4 Ma. Ichthyolith stratigraphy shows sedimentation rates of 0.2 to 0.3 mm/1000 years from 65 to 5 Ma. The observed sedimentological variations can be explained in terms of present sedimentation patterns in the central North Pacific and by the NNW motion of the Pacific plate during the Cenozoic

Geologic Map of the Thaumasia Region, Mars

Science.gov (United States)

Dohm, Janes M.; Tanaka, Kenneth L.; Hare, Trent M.

2001-01-01

). The medium-resolution Viking images used for mapping and base preparation also formed the basis of the 1:2,000,000 scale subquadrangle series. Earlier geologic maps of all or parts of the region include: (1) maps of the Phoenicis Lacus, Coprates, Thaumasia, and Argyre quadrangles at 1:5,000,000 scale based mainly on Mariner 9 images (respectively, Masursky and others, 1978; McCauley, 1978; McGill, 1978; and Hodges, 1980), (2) the global map of Mars at 1:25,000,000 (Scott and Carr, 1978) compiled largely from the 1:5,000,000 scale geologic maps, (3) maps showing lava flows in the Tharsis region at 1:2,000,000 scale compiled from Viking and Mariner 9 images (Scott, 1981; Scott and Tanaka, 1981a, b; Scott and others, 1981), (4) the map of the western equatorial region of Mars at 1:15,000,000 scale based on Viking images (Scott and Tanaka, 1986), and (5) the map of the Valles Marineris region at 1:2,000,000 scale compiled from Viking images (Witbeck and others, 1991). The previous maps have described the overall geology and geomorphology of the region but have not unraveled the detailed stratigraphy and complex evolution of this unique and geologically diverse martian province. The main purpose of this comprehensive mapping project is to reconstruct the stratigraphic, structural, and erosional histories of the Thaumasia region. The region is the last major province of the Tharsis region to undergo detailed structural mapping using Viking images; its history is essential to documenting the overall tectonic history of Tharsis. Other provinces of Tharsis that have been structurally mapped include Syria Planum (Tanaka and Davis, 1988), Tempe Terra and Ulysses Patera (Scott and Dohm, 1990b), and Alba Patera (Tanaka, 1990). Another primary mapping objective is to determine the region's volcanic history and assess the relations among fault systems and volcanoes (Wise and others, 1979; Scott and Tanaka, 1980; Whitford-Stark, 1982; Scott and Dohm, 1990a). A secondary mapping

Combined NLCG/SBI magnetotelluric data inversion for recognition of complex geological structures

International Nuclear Information System (INIS)

Michal Stefaniuk

2009-01-01

Complete text of publication follows. Geological interpretation of magnetotelluric data is a subject of some misunderstandings. Simplified geometrically and well contrasted in resistivity models do not response for real geological environment. The aim of outstripping magnetotelluric works widely made in Polish Outer Carpathians, is general structural and lithological recognising of geological environment and distinguishing of areas where oil prospection will be projected. The geological medium is formed by sedimentary formations, strongly deformed and containing relatively thin layers with essentially differentiated parameters, overlying rather flat, high resistivity basement. Application of simplified strongly contrasted interpretation model with fluently changing parameters gives frequently results not corresponding with geological reality. Presented analysis is based on surveys located in marginal zone of Carpathianst in the area relatively well recognised, where interpreted structural and lithologic model rather well reflects real geological medium. Then, it was used as reference model for obtained results of MT data inversion. Magnetotelluric continuous profiling located along reflection seismic profile, between two deep boreholes was made. Set of results of computations allows to evaluate of effectiveness of used procedures and suggest optimum way of dealing. First stage of data interpretation was based on 1D and EMAP inversion. The section was then applied as starting model for 2D NLCG inversion. Results of this method give rather generalized resistivity distribution well reflecting structure of flysch cover but not adequate for the basement. This models was applied as starting models for SBI inversion constrained by borehole data. Results of SBI procedure well reflects relatively flat complexes of the basement, but are rather unrealistic for folded flysch cover. The another NLCG inversion was computed with stabilised model of basement obtained from SBI

Stratigraphy and structure of the northern and western flanks of the Black Hills Uplift, Wyoming, Montana, and South Dakota

International Nuclear Information System (INIS)

Robinson, C.S.; Mapel, W.J.; Bergendahl, M.H.

1981-01-01

This report describes the stratigraphy and structure of an area of about 5000 square miles in northeastern Wyoming and adjacent parts of Montana and South Dakota. The area includes the northern end and part of the western side of the Black Hills Uplift and the adjoining part of the Powder River Basin. About 11,000 ft of sedimentary rocks ranging in age from Mississippian to Early Tertiary are exposed in the area, not including surficial deposits of Tertiary (.) and Quaternary age. Oil is produced from several fields on the wet side of the Black Hills Uplift in Wyoming. Bentonite is mined at many places. The Fort Union and Wasatch Formations contain large reserves of sub-bituminous coal, and Lakota Formation contains some bituminous coal

Geologic control on the evolution of the inner shelf morphology offshore of the Mississippi barrier islands, northern Gulf of Mexico, USA

Science.gov (United States)

Flocks, James G.; Kindinger, Jack G.; Kelso, Kyle W.

2015-01-01

Between 2008 and 2013, high-resolution geophysical surveys were conducted around the Mississippi barrier islands and offshore. The sonar surveys included swath and single-beam bathymetry, sidescan, and chirp subbottom data collection. The geophysical data were groundtruthed using vibracore sediment collection. The results provide insight into the evolution of the inner shelf and the relationship between the near surface geologic framework and the morphology of the coastal zone. This study focuses on the buried Pleistocene fluvial deposits and late Holocene shore-oblique sand ridges offshore of Petit Bois Island and Petit Bois Pass. Prior to this study, the physical characteristics, evolution, and interrelationship of the ridges between both the shelf geology and the adjacent barrier island platform had not been evaluated. Numerous studies elsewhere along the coastal margin attribute shoal origin and sand-ridge evolution to hydrodynamic processes in shallow water (<20 m). Here we characterize the correlation between the geologic framework and surface morphology and demonstrate that the underlying stratigraphy must also be considered when developing an evolutionary conceptual model. It is important to understand this near surface, nearshore dynamic in order to understand how the stratigraphy influences the long-term response of the coastal zone to sea-level rise. The study also contributes to a growing body of work characterizing shore-oblique sand ridges which, along with the related geology, are recognized as increasingly important components to a nearshore framework whose origins and evolution must be understood and inventoried to effectively manage the coastal zone.

3D geological modeling of the transboundary Berzdorf-Radomierzyce basin in Upper Lusatia (Germany/Poland)

Science.gov (United States)

Woloszyn, Iwona; Merkel, Broder; Stanek, Klaus

2017-07-01

The management of natural resources has to follow the principles of sustainable development. Therefore, before starting new mining activities, it should be checked, whether existing deposits have been completely exploited. In this study, a three-dimensional (3D) cross-border geologic model was created to generalize the existing data of the Neogene Berzdorf-Radomierzyce basin, located in Upper Lusatia on the Polish-German border south of the city of Görlitz-Zgorzelec. The model based on boreholes and cross sections of abandoned and planned lignite fields was extended to the Bernstadt and Neisse-Ręczyn Graben, an important tectonic structure at the southern rim of the basin. The partly detailed stratigraphy of Neogene sequences was combined to five stratigraphic units, considering the lithological variations and the main tectonic structures. The model was used to check the ability of a further utilization of the Bernstadt and Neisse-Ręczyn Graben, containing lignite deposits. Moreover, it will serve as a basis for the construction of a 3D cross-border groundwater model, to investigate the groundwater flow and transport in the Miocene and Quaternary aquifer systems. The large amount of data and compatibility with other software favored the application of the 3D geo-modeling software Paradigm GOCAD. The results demonstrate a very good fit between model and real geological boundaries. This is particularly evident by matching the modeled surfaces to the implemented geological cross sections. The created model can be used for planning of full-scale mining operations in the eastern part of the basin (Radomierzyce).

Application of VSP to geological investigation; P ha oyobi S ha VSP wo mochiita shinso chishitsu chosa

Energy Technology Data Exchange (ETDEWEB)

Kinugasa, Y [Geological Survey of Japan, Tsukuba (Japan); Feng, S; Sugiyama, T; Ishikawa, K [Chuoh Kaihatsu Corp., Tokyo (Japan)

1997-05-27

Discussed in this paper are the P-wave and S-wave zero-offset VSPs carried out utilizing boreholes located in Nada Ward, Kobe City, and Hokudan-cho, Hyogo Prefecture, as part of the deep layer boring survey following Hanshin Earthquake Disaster. This effort aims at the elucidation of P-wave and S-wave velocity structures, high-precision identification of data obtained by the surface reflection method, and collection of basic data for active faults investigation in the future. Among the velocity structures obtained for various layers, the S-wave velocity structures in particular agree with the stratigraphy excellently and may be utilized in seismic analyses to be conducted in the future. Reflection from geological boundaries is received with precision, providing accurate information about correlation between reflection and geological cross sections. The records will be useful in formulating plans for reflection surveys for instance of the boundary between the Osaka group and Kobe group. Generally speaking, reflection coefficients are large when the reflection is from a boundary where difference is great in elastic wave impedance (mainly difference in velocity). In the case of the boundary between the Kobe group and granite in Awaji Island, however, no strong reflection is found despite the great difference in velocity. This is attributed to the complicated, sharp inclination of the basement rock and to its weathering. 4 refs., 8 figs.

The "chessboard" classification scheme of mineral deposits: Mineralogy and geology from aluminum to zirconium

Science.gov (United States)

Dill, Harald G.

2010-06-01

metamorphic) and structures. Cross sections and images illustrate the common ore types of each commodity. Ore takes priority over the mineral. The minerals and host rocks are listed by their chemical and mineralogical compositions, respectively, separated from the text but supplemented with cross-references to the columns and lines, where they prevalently occur. A metallogenetic-geodynamic overview is given at the bottom of each column in the spreadsheet. It may be taken as the "sum" or the " mean" of a number of geodynamic models and ideas put forward by the various researchers for all the deposits pertaining to a certain clan of lithology or structure. This classical or conservative view of metallotects related to the common plate tectonic settings is supplemented by an approach taken for the first time for such a number of deposits, using the concepts of sequence stratigraphy. This paper, so as to say, is a "launch pad" for a new mindset in metallogenesis rather than the final result. The relationship supergene-hypogene and syngenetic-epigenetic has been the topic of many studies for ages but to keep them as separate entities is often unworkable in practice, especially in the so-called epithermal or near-surface/shallow deposits. Vein-type and stratiform ore bodies are generally handled also very differently. To get these different structural elements (space) and various mineralizing processes (time) together and to allow for a forward modeling in mineral exploration, architectural elements of sequence stratigraphy are adapted to mineral resources. Deposits are geological bodies which need accommodation space created by the environment of formation and the tectonic/geodynamic setting through time. They are controlled by horizontal to subhorizontal reference planes and/or vertical structures. Prerequisites for the deposits to evolve are thermal and/or mechanical gradients. Thermal energy is for most of the settings under consideration deeply rooted in the mantle. A

Mine wastes: characterization, treatment and environmental impacts

National Research Council Canada - National Science Library

Lottermoser, Bernd G

2010-01-01

... to follow rather classical lines, focused on the teaching of palaeontology, crystallography, mineralogy, petrology, stratigraphy, sedimentology, structural geology, and ore deposit geology. However, today and in the future, earth science teachers and students also need to be familiar with other subject areas. In particular, earth...

Research on sequence stratigraphy of Shuixigou group, jurassic in Yili basin

International Nuclear Information System (INIS)

Li Shengfu; Wang Guo; Wei Anxin; Qi Junrang; Zhang Zhongwang

2006-01-01

The Shuixigou Group, Jurassic in Yili basin is a set of coal-bearing clastic formation formed under basically consistent tectonic stress and sedimentary environment. In the middle of the Group (Sangonghe Formation) abrupt changes appear in the lithology and the colour of rocks, and an abrupt turning in logging curve appears correspondingly. Using the point view of sequence stratigraphy, the authors analyse the above phenomenon in aspects of the chrono-stratigraphy, the lithology, the sedimentary system tract, the sedimentary rhythum, as well as the interpretation of logging curves, and suggest that a unconformity surface (or a sequence boundary) exists in the middle of the Group, and try make a re-division of sequence stratigraphy for the Shuixigou Group. (authors)

Geologic reconnaissance of the Hot Springs Mountains, Churchill County, Nevada

Science.gov (United States)

Voegtly, Nickolas E.

1981-01-01

A geologic reconnaissance of the Hot Springs Mountains and adjacent areas, which include parts of the Brady-Hazen and the Stillwater-Soda Lake Known Geothermal Resource Areas, during June-December 1975, resulted in a reinterpretation of the nature and location of some Basin and Range faults. In addition, the late Cenozoic stratigraphy has been modified, chiefly on the basis of radiometric dates of volcanic rocks by U.S. Geological Survey personnel and others. The Hot Springs Mountains are in the western part of the Basin and Range province, which is characterized by east-west crustal extension and associated normal faulting. In the surrounding Trinity, West Humboldt, Stillwater, and Desert Mountains, Cenozoic rocks overlie ' basement ' rocks of the Paleozoic and Mesozoic age. A similar relation is inferred in the Hot Springs Mountains. Folding and faulting have taken place from the late Tertiary to the present. (USGS)

Geology and mineral occurences of braquiantidinal do Lontra - GO

International Nuclear Information System (INIS)

Macambira, J.B.

1983-01-01

This work involved the geological mapping (in the scale 1:60.000) of an area of 800 square kilometers in the nortwestern part of the state of Goias, near and east of the Araguaia river. Based on the stratigraphy, metamorphism, geochronology, magmatism and mineral deposits hypotheses on the geological evolution of the region are discussed. The area studied belongs to the Precambrian Araguaia Fold Belt. The oldest rocks identified are trondhjemitic gneisses and on these rocks was deposited a sedimentary sequence with minor volcanics of a geosynclinal type. The stratigraphic column of Abreu (1978) was adopted with minor modifications. The basement, of transamazonic age (2000 Ma), consists mostly of gneiss, migmatite, granite gneiss and amphibolite. The metasediments belongs to the lower unit (Estrondo Group) of the Supergroup Baixo Araguaia. The Estrondo Group, of brasilian age (600 Ma), consists in the area of the lowermost Morro do Campo Formation, mainly quartzite and amphibolite, which give the high relief of the brachyanticlines of Lontra and Ramal do Lontra.(author)

Fluvial-deltaic sedimentation and stratigraphy of the ferron sandstone

Science.gov (United States)

Anderson, P.B.; Chidsey, T.C.; Ryer, T.A.

1997-01-01

East-central Utah has world-class outcrops of dominantly fluvial-deltaic Turonian to Coniacian aged strata deposited in the Cretaceous foreland basin. The Ferron Sandstone Member of the Mancos Shale records the influences of both tidal and wave energy on fluvial-dominated deltas on the western margin of the Cretaceous western interior seaway. Revisions of the stratigraphy are proposed for the Ferron Sandstone. Facies representing a variety of environments of deposition are well exposed, including delta-front, strandline, marginal marine, and coastal-plain. Some of these facies are described in detail for use in petroleum reservoir characterization and include permeability structure.

Correlation between high resolution sequence stratigraphy and mechanical stratigraphy for enhanced fracture characteristic prediction

Science.gov (United States)

Al Kharusi, Laiyyan M.

Sequence stratigraphy relates changes in vertical and lateral facies distribution to relative changes in sea level. These relative changes in carbonates effect early diagenesis, types of pores, cementation and dissolution patterns. As a result, in carbonates, relative changes in sea level significantly impact the lithology, porosity, diagenesis, bed and bounding surfaces which are all factors that control fracture patterns. This study explores these relationships by integrating stratigraphy with fracture analysis and petrophysical properties. A special focus is given to the relationship between mechanical boundaries and sequence stratigraphic boundaries in three different settings: (1) Mississippian strata in Sheep Mountain Anticline, Wyoming, (2) Mississippian limestones in St. Louis, Missouri, and (3) Pennsylvanian limestones intermixed with elastics in the Paradox Basin, Utah. The analysis of these sections demonstrate that a fracture hierarchy exists in relation to the sequence stratigraphic hierarchy. The majority of fractures (80%) terminate at genetic unit boundaries or the internal flooding surface that separates the transgressive from regressive hemicycle. Fractures (20%) that do not terminate at genetic unit boundaries or their internal flooding surface terminate at lower order sequence stratigraphic boundaries or their internal flooding surfaces. Secondly, the fracture spacing relates well to bed thickness in mechanical units no greater than 0.5m in thickness but with increasing bed thickness a scatter from the linear trend is observed. In the Paradox Basin the influence of strain on fracture density is illustrated by two sections measured in different strain regimes. The folded strata at Raplee Anticline has higher fracture densities than the flat-lying beds at the Honaker Trail. Cemented low porosity rocks in the Paradox Basin do not show a correlation between fracture pattern and porosity. However velocity and rock stiffness moduli's display a slight

Geology of the host formation for the new hydraulic fracturing facility at Oak Ridge National Laboratory

International Nuclear Information System (INIS)

Haase, C.S.; Stow, S.H.; Zucker, C.L.; University of Tennessee, Knoxville)

1985-01-01

Liquid low-level radioactive wastes are disposed of at Oak Ridge National Laboratory (ORNL) by the hydrofracture process. Wastes are mixed with cement and other additives to form a slurry that is injected into a low permeability shale at 300-m depth. Important properties for a host shale formation at a hydrofracture facility include: (1) predictable fracture behavior; (2) hydrologic isolation; and (3) favorable mineralogy and geochemistry to retard radionuclide migration and enhance grout stability. The stratigraphy, petrology, diagenesis, structural geology, and hydrology of the Pumpkin Valley Shale host formation at the ORNL site are summarized and discussed in light of these three properties. Empirical data from hydrofracture operations at ORNL over the past 25 years suggest that many aspects of the Pumpkin Valley Shale make it favorable for use as a host. This observation agrees with analysis of several aspects of the Pumpkin Valley Shale geology at the ORNL site. Although presently available data suggest that the permeability of the Pumpkin Valley Shale is low and that it should provide sufficient hydrologic isolation, more data are needed to properly evaluate this aspect of host formation performance

Automation method to identify the geological structure of seabed using spatial statistic analysis of echo sounding data

Science.gov (United States)

Kwon, O.; Kim, W.; Kim, J.

2017-12-01

Recently construction of subsea tunnel has been increased globally. For safe construction of subsea tunnel, identifying the geological structure including fault at design and construction stage is more than important. Then unlike the tunnel in land, it's very difficult to obtain the data on geological structure because of the limit in geological survey. This study is intended to challenge such difficulties in a way of developing the technology to identify the geological structure of seabed automatically by using echo sounding data. When investigation a potential site for a deep subsea tunnel, there is the technical and economical limit with borehole of geophysical investigation. On the contrary, echo sounding data is easily obtainable while information reliability is higher comparing to above approaches. This study is aimed at developing the algorithm that identifies the large scale of geological structure of seabed using geostatic approach. This study is based on theory of structural geology that topographic features indicate geological structure. Basic concept of algorithm is outlined as follows; (1) convert the seabed topography to the grid data using echo sounding data, (2) apply the moving window in optimal size to the grid data, (3) estimate the spatial statistics of the grid data in the window area, (4) set the percentile standard of spatial statistics, (5) display the values satisfying the standard on the map, (6) visualize the geological structure on the map. The important elements in this study include optimal size of moving window, kinds of optimal spatial statistics and determination of optimal percentile standard. To determine such optimal elements, a numerous simulations were implemented. Eventually, user program based on R was developed using optimal analysis algorithm. The user program was designed to identify the variations of various spatial statistics. It leads to easy analysis of geological structure depending on variation of spatial statistics

Geologic map of the St. Joe quadrangle, Searcy and Marion Counties, Arkansas

Science.gov (United States)

Hudson, Mark R.; Turner, Kenzie J.

2009-01-01

This map summarizes the geology of the St. Joe 7.5-minute quadrangle in the Ozark Plateaus region of northern Arkansas. Geologically, the area lies on the southern flank of the Ozark dome, an uplift that exposes oldest rocks at its center in Missouri. Physiographically, the St. Joe quadrangle lies within the Springfield Plateau, a topographic surface generally held up by Mississippian cherty limestone. The quadrangle also contains isolated mountains (for example, Pilot Mountain) capped by Pennsylvanian rocks that are erosional outliers of the higher Boston Mountains plateau to the south. Tomahawk Creek, a tributary of the Buffalo River, flows through the eastern part of the map area, enhancing bedrock erosion. Exposed bedrock of this region comprises an approximately 1,300-ft-thick sequence of Ordovician, Mississippian, and Pennsylvanian carbonate and clastic sedimentary rocks that have been mildly deformed by a series of faults and folds. The geology of the St. Joe quadrangle was mapped by McKnight (1935) as part of a larger area at 1:125,000 scale. The current map confirms many features of this previous study, but it also identifies new structures and uses a revised stratigraphy. Mapping for this study was conducted by field inspection of numerous sites and was compiled as a 1:24,000-scale geographic information system (GIS) database. Locations and elevations of sites were determined with the aid of a global positioning satellite receiver and a hand-held barometric altimeter that was frequently recalibrated at points of known elevation. Hill-shade-relief and slope maps derived from a U.S. Geological Survey 10-m digital elevation model as well as U.S. Geological Survey orthophotographs from 2000 were used to help trace ledge-forming units between field traverses within the Upper Mississippian and Pennsylvanian part of the stratigraphic sequence. Strikes and dips of beds were typically measured along stream drainages or at well-exposed ledges. Beds dipping less

New data on the geological environment of the natural reactors

International Nuclear Information System (INIS)

Gauthier-Lafaye, F.; Besnus, Y.; Weber, F.

1978-01-01

Since the Libreville symposium in 1975 knowledge of the geological environment of the reactors has advanced as a result of a more extensive study of the Francevillian uranium deposits. In the Oklo deposit a detailed stratigraphy of the Cl bed (uraniferous mineralized bed) has been established, making it possible to re-establish stratigraphically the position of the natural reactors. A tectonic analysis of the Oklo deposit has revealed the special features of the Oklo structure and the reaction zones situated in the shear troughs. Petrographic studies have revealed the presence of two types of ore with distinct modes of formation. In the first case, the role played by organic materials seems predominant, while in the second case migrations of oxidizing solutions are the main source of the reconcentrations. Finally, a geochemical study made of samples from Oklo and Okelobondo points to the existence of an ''isolated'' geochemical phase containing uranium and a certain number of trace elements. This phase is associated with the organic material. This study also deals with the migration of lead at Oklo and Mounana. (author)

Enhanced recovery of subsurface geological structures using compressed sensing and the Ensemble Kalman filter

KAUST Repository

Sana, Furrukh

2015-07-26

Recovering information on subsurface geological features, such as flow channels, holds significant importance for optimizing the productivity of oil reservoirs. The flow channels exhibit high permeability in contrast to low permeability rock formations in their surroundings, enabling formulation of a sparse field recovery problem. The Ensemble Kalman filter (EnKF) is a widely used technique for the estimation of subsurface parameters, such as permeability. However, the EnKF often fails to recover and preserve the channel structures during the estimation process. Compressed Sensing (CS) has shown to significantly improve the reconstruction quality when dealing with such problems. We propose a new scheme based on CS principles to enhance the reconstruction of subsurface geological features by transforming the EnKF estimation process to a sparse domain representing diverse geological structures. Numerical experiments suggest that the proposed scheme provides an efficient mechanism to incorporate and preserve structural information in the estimation process and results in significant enhancement in the recovery of flow channel structures.

Enhanced recovery of subsurface geological structures using compressed sensing and the Ensemble Kalman filter

KAUST Repository

Sana, Furrukh; Katterbauer, Klemens; Al-Naffouri, Tareq Y.; Hoteit, Ibrahim

2015-01-01

Recovering information on subsurface geological features, such as flow channels, holds significant importance for optimizing the productivity of oil reservoirs. The flow channels exhibit high permeability in contrast to low permeability rock formations in their surroundings, enabling formulation of a sparse field recovery problem. The Ensemble Kalman filter (EnKF) is a widely used technique for the estimation of subsurface parameters, such as permeability. However, the EnKF often fails to recover and preserve the channel structures during the estimation process. Compressed Sensing (CS) has shown to significantly improve the reconstruction quality when dealing with such problems. We propose a new scheme based on CS principles to enhance the reconstruction of subsurface geological features by transforming the EnKF estimation process to a sparse domain representing diverse geological structures. Numerical experiments suggest that the proposed scheme provides an efficient mechanism to incorporate and preserve structural information in the estimation process and results in significant enhancement in the recovery of flow channel structures.

Stratigraphy and Evolution of Delta Channel Deposits, Jezero Crater, Mars

Science.gov (United States)

Goudge, T. A.; Mohrig, D.; Cardenas, B. T.; Hughes, C. M.; Fassett, C. I.

2017-01-01

The Jezero impact crater hosted an open-basin lake that was active during the valley network forming era on early Mars. This basin contains a well exposed delta deposit at the mouth of the western inlet valley. The fluvial stratigraphy of this deposit provides a record of the channels that built the delta over time. Here we describe observations of the stratigraphy of the channel deposits of the Jezero western delta to help reconstruct its evolution.

Lithofacies and sequence stratigraphic description of the upper part of the Avon Park Formation and the Arcadia Formation in U.S. Geological Survey G–2984 test corehole, Broward County, Florida

Science.gov (United States)

Cunningham, Kevin J.; Robinson, Edward

2017-07-18

Rock core and sediment from U.S. Geological Survey test corehole G–2984 completed in 2011 in Broward County, Florida, provide an opportunity to improve the understanding of the lithostratigraphic, sequence stratigraphic, and hydrogeologic framework of the intermediate confining unit and Floridan aquifer system in southeastern Florida. A multidisciplinary approach including characterization of sequence stratigraphy, lithofacies, ichnology, foraminiferal paleontology, depositional environments, porosity, and permeability was used to describe the geologic samples from this test corehole. This information has produced a detailed characterization of the lithofacies and sequence stratigraphy of the upper part of the middle Eocene Avon Park Formation and Oligocene to middle Miocene Arcadia Formation. This enhancement of the knowledge of the sequence stratigraphic framework is especially important, because subaerial karst unconformities at the upper boundary of depositional cycles at various hierarchical scales are commonly associated with secondary porosity and enhanced permeability in the Floridan aquifer system.

Mineral resources, geologic structure, and landform surveys

Science.gov (United States)

Lattman, L. H.

1973-01-01

The use of ERTS-1 imagery for mineral resources, geologic structure, and landform surveys is discussed. Four categories of ERTS imagery application are defined and explained. The types of information obtained by the various multispectral band scanners are analyzed. Samples of land use maps and tectoning and metallogenic models are developed. It is stated that the most striking features visible on ERTS imagery are regional lineaments, or linear patterns in the topography, which reflect major fracture zones extending upward from the basement of the earth.

Grand Bank seabed and shallow subsurface geology in relation to subsea engineering design

Energy Technology Data Exchange (ETDEWEB)

Sonnichsen, G.V.; King, E.L. [Natural Resources Canada, Dartmouth, NS (Canada). Geological Survey of Canada

2005-07-01

An overview of the surficial and subseabed geology of the northeastern section of the Newfoundland Grand Banks was presented with particular reference to the Jeanne d'Arc Basin. The stratigraphy of the upper 100 metres below seafloor has been interpreted from high-resolution seismic reflection data, surficial sediment samples and geotechnical borehole data. This paper described the character and strength properties of nearby seabed sediments and addressed the issue of seabed scour by icebergs, which is the main process threatening subsea facilities. Other potential geohazards such as shallow gas, buried channels and sediment mobility are not considered to be major barriers to offshore development in the Jeanne d'Arc Basin. However, drifting icebergs with large drafts often impact the seabed, producing either linear furrows or circular pits. The constraints to subsea design and construction were identified. It was noted that regional geological characterization is needed to help select the location for offshore platforms as well as routes for excavating trenches for subsea installations for offshore hydrocarbon development. Updated regional surficial and near-seabed stratigraphy is needed to predict foundation conditions beyond ground truth from isolated geotechnical borehole investigations. This paper described the Grand Banks regional setting, regional geology, near-surface sediment in the northeastern Grand Banks, and Quaternary sediments in the northeastern Grand Banks with reference to the Grand Banks Drift, Adolphus Sand, and the Grand Banks Sand and Gravel Formation. Risk assessments have shown that well heads and manifolds should be installed below the seabed in order to avoid damage by seabed-scouring icebergs and that the design scour depth should be re-examined for future subsea development. It was suggested that more emphasis on gathering multibeam bathymetric data and repetitive mapping of the seabed will better define scour risk. 57 refs., 3

The shallow stratigraphy and sand resources offshore of the Mississippi Barrier Islands

Science.gov (United States)

Twichell, David; Pendleton, Elizabeth A.; Baldwin, Wayne; Foster, David; Flocks, James; Kelso, Kyle; DeWitt, Nancy; Pfeiffer, William; Forde, Arnell; Krick, Jason; Baehr, John

2011-01-01

Coastal Mississippi is protected by a series of barrier islands ranging in length from 10-25 kilometers that are less than 2 kilometers wide. The majority of these islands comprise the Gulf Islands National Seashore (GUIS), an ecologically diverse shoreline that provides habitat for wildlife including migratory birds and endangered animals. The majority of GUIS is submerged, and aquatic environments include dynamic tidal inlets, ebb-tide deltas, and seagrass beds. The islands are in a state of decline, with land areas severely reduced during the past century by storms, sea-level rise, and human alteration. Morton (2008) estimates that since the mid-1800s up to 64 percent of island surface area has been lost. Heavy damage was inflicted in 2005 by Hurricane Katrina, which passed by as a Category 3 storm and battered the islands with winds of more than 160 kilometers per hour and a storm surge up to 9 meters. Since 2007, the U.S. Geological Survey (USGS), in collaboration with the National Park Service, has been mapping the seafloor and substrate around the islands as part of the USGS Northern Gulf of Mexico Ecosystem Change and Hazard Susceptibility project. The purpose of these investigations is to characterize the near-surface stratigraphy and identify the influence it may have on island evolution and fate. In 2009, this effort provided the basis for a collaborative effort with the U.S. Army Corps of Engineers (USACE) to expand the investigation outside of GUIS boundaries as part of the Mississippi Coastal Improvement Project (MsCIP). The MsCIP program consists of structural, nonstructural, and environmental project elements to restore portions of coastal Mississippi and GUIS affected by storm impact. The project includes the placement of sand along the islands, both on the present beaches and within the littoral zone, to mitigate shoreline erosion and breaching. This action requires the location and assessment of offshore sand or sediment deposits that can provide

The application of structure from motion (SfM) to identify the geological structure and outcrop studies

Science.gov (United States)

Saputra, Aditya; Rahardianto, Trias; Gomez, Christopher

2017-07-01

Adequate knowledge of geological structure is an essential for most studies in geoscience, mineral exploration, geo-hazard and disaster management. The geological map is still one the datasets the most commonly used to obtain information about the geological structure such as fault, joint, fold, and unconformities, however in rural areas such as Central Java data is still sparse. Recent progress in data acquisition technologies and computing have increased the interest in how to capture the high-resolution geological data effectively and for a relatively low cost. Some methods such as Airborne Laser Scanning (ALS), Terrestrial Laser Scanning (TLS), and Unmanned Aerial Vehicles (UAVs) have been widely used to obtain this information, however, these methods need a significant investment in hardware, software, and time. Resolving some of those issues, the photogrammetric method structure from motion (SfM) is an image-based method, which can provide solutions equivalent to laser technologies for a relatively low-cost with minimal time, specialization and financial investment. Using SfM photogrammetry, it is possible to generate high resolution 3D images rock surfaces and outcrops, in order to improve the geological understanding of Indonesia. In the present contribution, it is shown that the information about fault and joint can be obtained at high-resolution and in a shorter time than with the conventional grid mapping and remotely sensed topographic surveying. The SfM method produces a point-cloud through image matching and computing. This task can be run with open- source or commercial image processing and 3D reconstruction software. As the point cloud has 3D information as well as RGB values, it allows for further analysis such as DEM extraction and image orthorectification processes. The present paper describes some examples of SfM to identify the fault in the outcrops and also highlight the future possibilities in terms of earthquake hazard assessment, based on

Study on the estimation method of uplift during the late Quaternary by using river terraces (2). Stratigraphy of fluvial terraces along the Naka Rivers

International Nuclear Information System (INIS)

Hataya, Ryuta

2006-01-01

To develop the reliable method of terrace correlation and chronology, which is a key technique for uplift characterization in an inland area, verification of terrace correlation and chronology is examined along the Naka and Hoki rivers, Ibaraki and Tochigi Prefectures. The results obtained indicate that the basic concept of terrace correlation and chronology proposed by Hataya (2005). Also, weathering grade of terrace gravels is classified into 4 levels and shows a good agreement with the terrace chronology. It shows that weathering grade of terrace gravels is a good stratigraphic index. Therefore, it is stressed that it is very important to combine the information of geomorphologic stratigraphy, geomorphologic analysis, geologic stratigraphy, tephra chronology and numerical dating data comprehensively, in particular, is of great importance to obtain the detailed geomorphologic information. Furthermore, it is pointed out that it is probable to redefine the general idea of 'higher, middle, lower terraces' by tephra chronology and numerical dating data. For instance, MIS6 fluvial terrace that is important for uplift estimation is probably considered as 'a middle terrace in an inland area'. (author)

Geological heterogeneity: Goal-oriented simplification of structure and characterization needs

Science.gov (United States)

Savoy, Heather; Kalbacher, Thomas; Dietrich, Peter; Rubin, Yoram

2017-11-01

Geological heterogeneity, i.e. the spatial variability of discrete hydrogeological units, is investigated in an aquifer analog of glacio-fluvial sediments to determine how such a geological structure can be simplified for characterization needs. The aquifer analog consists of ten hydrofacies whereas the scarcity of measurements in typical field studies precludes such detailed spatial models of hydraulic properties. Of particular interest is the role of connectivity of the hydrofacies structure, along with its effect on the connectivity of mass transport, in site characterization for predicting early arrival times. Transport through three realizations of the aquifer analog is modeled with numerical particle tracking to ascertain the fast flow channel through which early arriving particles travel. Three simplification schemes of two-facies models are considered to represent the aquifer analogs, and the velocity within the fast flow channel is used to estimate the apparent hydraulic conductivity of the new facies. The facies models in which the discontinuous patches of high hydraulic conductivity are separated from the rest of the domain yield the closest match in early arrival times compared to the aquifer analog, but assuming a continuous high hydraulic conductivity channel connecting these patches yields underestimated early arrivals times within the range of variability between the realizations, which implies that the three simplification schemes could be advised but pose different implications for field measurement campaigns. Overall, the results suggest that the result of transport connectivity, i.e. early arrival times, within realistic geological heterogeneity can be conserved even when the underlying structural connectivity is modified.

Preliminary sequence stratigraphy and tectonic evolution of the Tokar Delta, (Southern Sudanese Red Sea)

OpenAIRE

Yagoub, Abbas Musa

2007-01-01

The study area comprises about 2500sq.Kms. From the seismic data acquired by the Oil Companies (Chevron 1975-76 Total 1980 and IPC 1992), thirty two seismic lines were selected Fig (2). Also synthetic seismograms of Suakin-1, Bashayer-1 A and Bashayer-2A wells are used. The stratigraphy and sedimentation of the Sudanese Red Sea can be placed into four major tectonic phases, Pre-rifting stratigraphy, Syn-Rift Pre-Salt Stratigarphy, Salt Phase and Syn-Rift Post Salt Stratigraphy. Basic conce...

Alluvial flash-flood stratigraphy of a large dryland river: the Luni River, Thar Desert, Western India

Science.gov (United States)

Carling, Paul; Leclair, Suzanne; Robinson, Ruth

2017-04-01

Detailed descriptions of the fluvial architecture of large dryland rivers are few, which hinders the understanding of stratigraphic development in aggradational settings. The aim of this study was to obtain new generic insight of the fluvial dynamics and resultant stratigraphy of such a river. The novelty of this investigation is that an unusually extensive and deep section across a major active dryland river was logged and the dated stratigraphy related to the behaviour of the discharge regimen. The results should help improve understanding of the stratigraphic development in modern dryland rivers and in characterizing oil, gas and groundwater reservoirs in the dryland geological record more generally. The Luni River is the largest river in the Thar desert, India, but yet details of the channel stratigraphy are sparse. Discharges can reach 14,000 m3s-1 but the bed is dry most of the year. GPS positioning and mm-resolution surveys within a 700m long, 5m deep trench enabled logging and photography of the strata associations, dated using optically-stimulated luminescence (OSL). The deposits consist of planar, sandy, upper-stage plane bed lamination and low-angle stratification, sandwiching less-frequent dune trough cross-sets. Mud clasts are abundant at any elevation. Water-ripple cross-sets or silt-clay layers occur rarely, usually near the top of sections. Aeolian dune cross-sets also appear sparsely at higher elevations. Consequently, the majority of preserved strata are due to supercritical flows. Localized deep scour causes massive collapse and soft-sediment deformation. Scour holes are infilled by rapidly-deposited massive sands adjacent to older bedded-deposits. Within bedform phase diagrams, estimated hydraulic parameters indicate a dominance of the upper-stage plane bed state, but the presence of dune cross-sets is also related to the flood hydrograph. Repeated deep scour results in units of deposition of different OSL ages (50 to 500 years BP) found at

Some geological effects of the search for radioactive minerals in the Canadian shield

International Nuclear Information System (INIS)

Lang, A.H.; Ruzicka, V.

1979-01-01

Priorities for funds and personnel to provide field and laboratory work related to finding and evaluating radioactive deposits, mainly those of uranium, also led directly and indirectly to greatly increased knowledge of the general geology of the Canadian Shield. The paper outlines some of the main advances made in these ways, as well as some minor ones. Main examples are: the acceleration of geological mapping and special studies of stratigraphy, structure and other aspects of several parts of the Shield, including the Archaean-Proterozoic boundary; the acquisition of modern equipment capable of making large numbers of isotope age determinations, which was soon applied to general problems in the Shield, including revision of its regional provinces and sub-provinces and the subdivision of Proterozoic time; the obtaining of modern equipment for X-ray identification of minerals and for several kinds of rock and mineral analyses, which soon allowed more advanced and more extensive mineral, petrological and trace element studies of various parts of the Shield and a general study of metallogenic provinces, illustrated by metallogenic maps, which stemmed from a metallogenic map for uranium. The development of Geiger counters and other detectors is outlined because of their relation to the map for uranium and so to aeroradiometric surveys. By 1960, 26 producing uranium mines had been developed from an estimated 12 000 occurrences carrying more than 0.05% U 3 O 8 equivalent. Current activities of the Geological Survey of Canada for radioactive minerals are summarized for whatever hints this may provide regarding further indirect effects

Near-surface stratigraphy and morphology, Mississippi Inner Shelf, northern Gulf of Mexico

Science.gov (United States)

Flocks, James G.; Kindinger, Jack; Kelso, Kyle W.; Bernier, Julie C.; DeWitt, Nancy T.; FitzHarris, Michael

2015-01-01

Over the past decade, the Mississippi Barrier Islands have been the focus of a comprehensive geologic investigation by the U.S. Geological Survey (USGS), in collaboration with the U.S. Army Corps of Engineers (USACE) and the National Park Service (NPS). The islands (Dauphin, Petite Bois, Horn, East Ship, West Ship, and Cat) are part of the Gulf Islands National Seashore (GUIS), and provide a diverse ecological habitat, protect the mainland from storm waves, and help maintain estuarine conditions within Mississippi Sound. Over the past century, the islands have been in a state of decline with respect to elevation and land-area loss. In 2005, the islands were severely impacted by Hurricane Katrina, which inundated them with a storm surge of 8 meters, causing severe shoreface erosion and widening breaches in Dauphin, West Ship, and Cat Islands. To evaluate the impact and fate of the islands, understanding their evolution and resiliency became a priority for the USGS under the Northern Gulf of Mexico Ecosystem Change and Hazard Susceptibility Project. The project formed the basis for collaboration with the USACE Mississippi Coastal Improvement Project, which is intended to restore portions of coastal Mississippi and GUIS affected by storm impact. Since then, many studies have contributed to our understanding of the islands’ morphology and nearshore stratigraphy. This report expands upon the nearshore component to provide a stratigraphic and morphologic assessment offshore of Petit Bois Island.

Geologic youth of galapagos islands confirmed by marine stratigraphy and paleontology.

Science.gov (United States)

Hickman, C S; Lipps, J H

1985-03-29

Six distinctive types of fossiliferous marine deposits occur on the Galádpagos Islands that provide evidence for the age of emergence of the islands above sea level and hence a maximum age for the islands' terrestrial biota. These subtidal to supratidal deposits include (i) volcanic tuffs with fossils, (ii) limestones and sandstones interbedded with basalt, (iii) terrace deposits, (iv) beach rock, (v) supratidal talus deposits, and (vi) recently uplifted tidal and subtidal rocks and sand. With the exception of (vi), the deposits were previously assigned ages varying from Miocene to Pleistocene, but all are less than about 2 million years old. This age, together with independently determined geologic ages, indicate that the islands emerged from the sea relatively recently and that all evolution of the islands' unique terrestrial biota occurred within the past 3 to 4 million years.

Coalfields west half Cumberland County, Nova Scotia

Energy Technology Data Exchange (ETDEWEB)

Copeland, M J

1958-01-01

A geologic survey of the coal fields of the western half of Cumberland County, Nova Scotia was performed including studies of the structural geology, stratigraphy, and paleontology of the area. One part of this survey included a spectrographic analysis of 55 coals for 23 elements. These analyses are presented in tabular form.

Preliminary stratigraphy and facies analysis of the Upper Cretaceous Kaguyak Formation, including a brief summary of newly discovered oil stain, upper Alaska Peninsula

Science.gov (United States)

Wartes, Marwan A.; Decker, Paul L.; Stanley, Richard G.; Herriott, Trystan M.; Helmold, Kenneth P.; Gillis, Robert J.

2013-01-01

The Alaska Division of Geological and Geophysical Surveys has an ongoing program aimed at evaluating the Mesozoic forearc stratigraphy, structure, and petroleum systems of lower Cook Inlet. Most of our field studies have focused on the Jurassic component of the petroleum system (this report). However, in late July and early August of 2012, we initiated a study of the stratigraphy and reservoir potential of the Upper Cretaceous Kaguyak Formation. The Kaguyak Formation is locally well exposed on the upper Alaska Peninsula (fig. 25) and was named by Keller and Reiser (1959) for a sequence of interbedded siltstone and sandstone of upper Campanian to Maastrichtian age that they estimated to be 1,450 m thick.Subsequent work by Detterman and Miller (1985) examined 900 m of section and interpreted the unit as the record of a prograding submarine fan.This interpretation of deep-water deposition contrasts with other Upper Cretaceous rocks exposed along the Alaska Peninsula and lower Cook Inlet that are generally described as nonmarine to shallow marine (Detterman and others, 1996; LePain and others, 2012).Based on foraminifera and palynomorphs from the COST No. 1 well, Magoon (1986) concluded that the Upper Cretaceous rocks were deposited in a variety of water depths and environments ranging from upper bathyal to nonmarine. During our recent fieldwork west and south of Fourpeaked Mountain, we similarly encountered markedly varying lithofacies in the Kaguyak Formation (fig. 25), and we also found oil-stained rocks that are consistent with the existence of an active petroleum system in Upper Cretaceous rocks on the upper Alaska Peninsula and in lower Cook Inlet. These field observations are summarized below.

Santos Basin Geological Structures Mapped by Cross-gradient Method

Science.gov (United States)

Jilinski, P.; Fontes, S. L.

2011-12-01

Introduction We mapped regional-scale geological structures localized in offshore zone Santos Basin, South-East Brazilian Coast. The region is dominated by transition zone from oceanic to continental crust. Our objective was to determine the imprint of deeper crustal structures from correlation between bathymetric, gravity and magnetic anomaly maps. The region is extensively studied for oil and gas deposits including large tectonic sub-salt traps. Our method is based on gradient directions and their magnitudes product. We calculate angular differences and cross-product and access correlation between properties and map structures. Theory and Method We used angular differences and cross-product to determine correlated region between bathymetric, free-air gravity and magnetic anomaly maps. This gradient based method focuses on borders of anomalies and uses its morphological properties to access correlation between their sources. We generated maps of angles and cross-product distribution to locate correlated regions. Regional scale potential fields maps of FA and MA are a reflection of the overlaying and overlapping effects of the adjacent structures. Our interest was in quantifying and characterizing the relation between shapes of magnetic anomalies and gravity anomalies. Results Resulting maps show strong correlation between bathymetry and gravity anomaly and bathymetry and magnetic anomaly for large strictures including Serra do Mar, shelf, continental slope and rise. All maps display the regional dominance of NE-SW geological structures alignment parallel to the shore. Special interest is presented by structures transgressing this tendency. Magnetic, gravity anomaly and bathymetry angles map show large correlated region over the shelf zone and smaller scale NE-SW banded structures over abyssal plane. From our interpretation the large band of inverse correlation adjacent to the shore is generated by the gravity effect of Serra do Mar. Disrupting structures including

Geology of the Wallula Gap Area, Washington

International Nuclear Information System (INIS)

Gardner, J.N.; Snow, M.G.; Fecht, K.R.

1981-12-01

This study focuses on the structure and stratigraphy of an 80-km 2 area at the southern margin of the Pasco Basin in Wallula Gap. Field stratigraphy, petrography, natural remanent magnetism, and major-element chemistry indicate that the tholeiitic basalt flows of the Wallula Gap area correlate with units of the Grande Ronde, Wanapum, and Saddle Mountains Formations of the Yakima Subgroup of the Columbia River Basalt Group. Flows of the Frenchman Springs, Umatilla, Pomona, Elephant Mountain, and Ice Harbor Mmebers are present in the area. The Frenchman Springs Member exposed in the Wallula Gap is more than 185 m thick and consists of eight to nine flows. Its thickness and possible contemporaneous structural deformation apparently prevented emplacement of both the Roza and Priest Rapids Members at this locality. Structural uplift of the Horse Heaven Hills began prior to extrusion of the Pomona flow. Both the Pomona and Elephant Mountain Members thin and pinch out over the crest of the uplift near Mound Pond. The Ice Harbor flow was apparently confined to the basin north of the Horse Heaven uplift, but an exposure at Mound Pond suggests it flowed through Wallula Gap as an intracanyon flow. The Wallula Gap fault zone trends N65 0 W and can be traced for at least 11 km along the north flank of the Horse Heaven Hills uplift. Where the fault intersects the Olympic-Wallowa Lineament at Van Sycle Canyon 8 km east of Wallula Gap, it is a broad zone of normal faulting, 300 m wide, with as much as 310 m of displacement of the basalt stratigraphy. Two faults occur in the northern portion of Van Sycle Canyon and define a graben trending N45 0 W. A third fault, roughly parallel to the Wallula Gap fault, transects the The Nub and offsets 14 m of Ice Harbor basalt

Macro- and micro- geodynamic of Terebliya-Riksk geodetic man-caused polygon of Ukrainian Carpathians influenced by specificities of structure-geological and hydro-geological conditions

Science.gov (United States)

Kulchyzkyy, A.; Serebryannyy, Y.; Tretyak, K.; Trevogo, I.; Zadoroznnyy, V.

2009-04-01

Terebliya-Riksk diversion power station is located on two levels ( with difference of 180m ) of south mountainside of Ukrainian Carpathians and separate parts of this power station lie inside rock. Therefore influential parameters of it's stability are geological, tectonic and hydrogeological conditions in complex. Monitoring of intensity and nature of displacements of flow ( pressure) pipe and other objects of power station with geoditic methods indicates that fluctuations of water-level in reservoir caused bouth by natural and artificial efects are of great influence on objects mentioned. Based on geodetical high-precision observations made by LeicaTPS 1201 robotic total station short-periodic components of fundamental vibrations which result in their destructive deformation were determined. Mathematical apparatus ( which uses function of Fourie series and theory of cinematic coefficients ) for displacements determinations of pressure pipe was disigned. Complex of engineering-geological surveys gave an opportunity to define the origin of macro- and micro- geodynamics movements of Terebliya-Riksk diversion power station region. Engineering-geological conditions which influence on power station structure most of all were determined as following : small foldings and cleavage areas appearances, also fluctuations of level of underground water (refered to hydrogeological conditions). Periodic micro-displacemets appearances ( which operate on reducing-stretching scheme) fixed on power station structure are turned to be in direct relation on to what exend reservoir is filled up. Permanent macro- displacements appearances ( which operates in north-west direction ) fixed on pressure pipe are the result sum of residual micro-displacements caused by return periodic movements and are determined by structure-geological, engineering-geological and tectonic conditions.

Preliminary Physical Stratigraphy and Geophysical Data From the USGS Dixon Core, Onslow County, North Carolina

Science.gov (United States)

Seefelt, Ellen L.; Gonzalez, Wilma Aleman B.; Self-Trail, Jean M.; Weems, Robert E.; Edwards, Lucy E.; Pierce, Herbert A.; Durand, Colleen T.

2009-01-01

In October through November 2006, scientists from the U. S. Geological Survey (USGS) Eastern Region Earth Surface Processes Team (EESPT) and the Raleigh (N.C.) Water Science Center (WSC), in cooperation with the North Carolina Geological Survey (NCGS) and the Onslow County Water and Sewer Authority (ONWASA), drilled a stratigraphic test hole and well in Onslow County, N.C. The Dixon corehole was cored on ONWASA water utility property north of the town of Dixon, N.C., in the Sneads Ferry 7.5-minute quadrangle at latitude 34deg33'35' N, longitude 77deg26'54' W (decimal degrees 34.559722 and -77.448333). The site elevation is 66.0 feet (ft) above mean sea level as determined using a Paulin precision altimeter. The corehole attained a total depth of 1,010 ft and was continuously cored by the USGS EESPT drilling crew. A groundwater monitoring well was installed in the screened interval between 234 and 254 ft below land surface. The section cored at this site includes Upper Cretaceous, Paleogene, and Neogene sediments. The Dixon core is stored at the NCGS Coastal Plain core storage facility in Raleigh. The Dixon corehole is the fourth and last in a series of planned North Carolina benchmark coreholes drilled by the USGS Coastal Carolina Project. These coreholes explore the physical stratigraphy, facies, and thickness of Cretaceous, Paleogene, and Neogene Coastal Plain sediments in North Carolina. Correlations of lithologies, facies, and sequence stratigraphy can be made with the Hope Plantation corehole, N.C., near Windsor in Bertie County (Weems and others, 2007); the Elizabethtown corehole, near Elizabethtown, N.C., in Bladen County (Self-Trail and others, 2004b); the Smith Elementary School corehole, near Cove City, N.C., in Craven County (Harris and Self-Trail, 2006; Crocetti, 2007); the Kure Beach corehole, near Wilmington, N.C., in New Hanover County (Self-Trail and others, 2004a); the Esso#1, Esso #2, Mobil #1, and Mobil #2 cores in Albermarle and Pamlico Sounds

Global mapping of stratigraphy of an old-master painting using sparsity-based terahertz reflectometry.

Science.gov (United States)

Dong, Junliang; Locquet, Alexandre; Melis, Marcello; Citrin, D S

2017-11-08

The process by which art paintings are produced typically involves the successive applications of preparatory and paint layers to a canvas or other support; however, there is an absence of nondestructive modalities to provide a global mapping of the stratigraphy, information that is crucial for evaluation of its authenticity and attribution, for insights into historical or artist-specific techniques, as well as for conservation. We demonstrate sparsity-based terahertz reflectometry can be applied to extract a detailed 3D mapping of the layer structure of the 17th century easel painting Madonna in Preghiera by the workshop of Giovanni Battista Salvi da Sassoferrato, in which the structure of the canvas support, the ground, imprimatura, underpainting, pictorial, and varnish layers are identified quantitatively. In addition, a hitherto unidentified restoration of the varnish has been found. Our approach unlocks the full promise of terahertz reflectometry to provide a global and detailed account of an easel painting's stratigraphy by exploiting the sparse deconvolution, without which terahertz reflectometry in the past has only provided a meager tool for the characterization of paintings with paint-layer thicknesses smaller than 50 μm. The proposed modality can also be employed across a broad range of applications in nondestructive testing and biomedical imaging.

Digital Stratigraphy: Contextual Analysis of File System Traces in Forensic Science.

Science.gov (United States)

Casey, Eoghan

2017-12-28

This work introduces novel methods for conducting forensic analysis of file allocation traces, collectively called digital stratigraphy. These in-depth forensic analysis methods can provide insight into the origin, composition, distribution, and time frame of strata within storage media. Using case examples and empirical studies, this paper illuminates the successes, challenges, and limitations of digital stratigraphy. This study also shows how understanding file allocation methods can provide insight into concealment activities and how real-world computer usage can complicate digital stratigraphy. Furthermore, this work explains how forensic analysts have misinterpreted traces of normal file system behavior as indications of concealment activities. This work raises awareness of the value of taking the overall context into account when analyzing file system traces. This work calls for further research in this area and for forensic tools to provide necessary information for such contextual analysis, such as highlighting mass deletion, mass copying, and potential backdating. © 2017 American Academy of Forensic Sciences.

Geologic framework and petroleum systems of Cook Inlet basin, south-central Alaska

Science.gov (United States)

LePain, D.L.; Stanley, R.G.; Helmold, K.P.; Shellenbaum, D.P.; Stone, D.M.; Hite, D.M.

2013-01-01

This report provides a comprehensive overview of the stratigraphy, structure, tectonics, and petroleum systems of the Cook Inlet basin, an important oil- and gas-producing region in south-central Alaska.

Sequence Stratigraphy of the Dakota Sandstone, Eastern San Juan Basin, New Mexico, and its Relationship to Reservoir Compartmentalization

Energy Technology Data Exchange (ETDEWEB)

Varney, Peter J.

2002-04-23

This research established the Dakota-outcrop sequence stratigraphy in part of the eastern San Juan Basin, New Mexico, and relates reservoir quality lithologies in depositional sequences to structure and reservoir compartmentalization in the South Lindrith Field area. The result was a predictive tool that will help guide further exploration and development.

Potential collapse due to geological structures influence in Seropan Cave, Gunung Kidul, Yogyakarta, Indonesia

Science.gov (United States)

Nugroho, B.; Pranantya, P. A.; Witjahjati, R.; Rofinus

2018-01-01

This study aims to estimate the potential collapse in the Seropan cave, based on the existing geological structure conditions in the cave. This is very necessary because in the Seropan cave will be built Microhydro installation for power plants. The electricity will be used to raise the underground river water in the cave to a barren soil surface, which can be used for surface irrigation. The method used is analysis the quality of rock mass along the cave. Analysis of rock mass quality using Geomechanical Classification or Rock Mass Rating (RMR), to determine the magnitude of the effect of geological structure on rock mass stability. The research path is divided into several sections and quality analysis is performed on each section. The results show that the influence of geological structure is very large and along the cave where the research there are several places that have the potential to collapse, so need to get serious attention in handling it. Nevertheless, the construction of this Microhydro installation can still be carried out by making a reinforcement on potentially collapsing parts

Geologic structure mapping database Spent Fuel Test - Climax, Nevada Test Site

International Nuclear Information System (INIS)

Yow, J.L. Jr.

1984-01-01

Information on over 2500 discontinuities mapped at the SFT-C is contained in the geologic structure mapping database. Over 1800 of these features include complete descriptions of their orientations. This database is now available for use by other researchers. 6 references, 3 figures, 2 tables

Stratigraphy and structure of eastern Syria across the Euphrates depression

Science.gov (United States)

Sawaf, Tarif; Al-Saad, Damen; Gebran, Ali; Barazangi, Muawia; Best, John A.; Chaimov, Thomas A.

1993-04-01

A N-S crustal-scale geotransect across the northern Arabian platform in eastern Syria reveals an alternating series of basement uplifts and basins separated by predominantly transpressional fault zones above an effectively uniform crust. Four major tectonic provinces are crossed along a 325 × 100 km corridor that extends from the Iraqi border in the south to the Turkish border in the north: the Rutbah uplift, the Euphrates depression, the Abd el Aziz structural zone, and the Qamichli uplift. These features are the manifestations of reactivated pre-Cenozoic structures that responded to forces acting along nearby Arabian plate boundaries, particularly Cenozoic convergence and collision along the margins of the northern Arabian platform i.e., the Bitlis suture and the East Anatolian fault in southern Turkey and the Zagros suture in Iran and Iraq. The database for this study consists of 3000 km of industry seismic reflection data, 28 exploratory wells, and geologic and Bouguer gravity maps. The deep crustal structure and, in part, the basement geometry along this transect are inferred from two-dimensional modeling of Bouguer gravity, whereas the shallow (about 8 km) structure is constrained primarily by well and seismic data. Features of the geotransect reveal: (1) A relatively uniform crustal column approximately 37 km thick with only minor crustal thinning beneath the Euphrates. Crustal thinning may be slightly more pronounced beneath the Euphrates (about 35 km) to the southeast of the transect where the Bouguer gravity anomaly is slightly higher. (2) Along the Euphrates depression, ongoing subsidence, which began during the Late Cretaceous, resulted in the deposition of at least 3 km of Late Cretaceous and Cenozoic rocks. The structural complexity of the Paleozoic and most of the Mesozoic sedimentary sections along the transect contrasts markedly with a relatively simple, flat-lying Cenozoic section along most of the transect. A notable exception is the Abd el Aziz

CONTRIBUTION OF SATELLITE ALTIMETRY DATA IN GEOLOGICAL STRUCTURE RESEARCH IN THE SOUTH CHINA SEA

Directory of Open Access Journals (Sweden)

T. D. Tran

2016-06-01

Full Text Available The study area is bordered on the East China Sea, the Philippine Sea, and the Australian-Indo plate in the Northeast, in the East and in the South, respectively. It is a large area with the diversely complicated conditions of geological structure. In spite of over the past many years of investigation, marine geological structure in many places have remained poorly understood because of a thick seawater layer as well as of the sensitive conflicts among the countries in the region. In recent years, the satellite altimeter technology allows of enhancement the marine investigation in any area. The ocean surface height is measured by a very accurate radar altimeter mounted on a satellite. Then, that surface can be converted into marine gravity anomaly or bathymetry by using the mathematical model. It is the only way to achieve the data with a uniform resolution in acceptable time and cost. The satellite altimetry data and its variants are essential for understanding marine geological structure. They provide a reliable opportunity to geologists and geophysicists for studying the geological features beneath the ocean floor. Also satellite altimeter data is perfect for planning the more detailed shipboard surveys. Especially, it is more meaningful in the remote or sparsely surveyed regions. In this paper, the authors have effectively used the satellite altimetry and shipboard data in combination. Many geological features, such as seafloor spreading ridges, fault systems, volcanic chains as well as distribution of sedimentary basins are revealed through the 2D, 3D model methods of interpretation of satellite-shipboard-derived data and the others. These results are improved by existing boreholes and seismic data in the study area.

Integrating sequence stratigraphy and rock-physics to interpret seismic amplitudes and predict reservoir quality

Science.gov (United States)

Dutta, Tanima

This dissertation focuses on the link between seismic amplitudes and reservoir properties. Prediction of reservoir properties, such as sorting, sand/shale ratio, and cement-volume from seismic amplitudes improves by integrating knowledge from multiple disciplines. The key contribution of this dissertation is to improve the prediction of reservoir properties by integrating sequence stratigraphy and rock physics. Sequence stratigraphy has been successfully used for qualitative interpretation of seismic amplitudes to predict reservoir properties. Rock physics modeling allows quantitative interpretation of seismic amplitudes. However, often there is uncertainty about selecting geologically appropriate rock physics model and its input parameters, away from the wells. In the present dissertation, we exploit the predictive power of sequence stratigraphy to extract the spatial trends of sedimentological parameters that control seismic amplitudes. These spatial trends of sedimentological parameters can serve as valuable constraints in rock physics modeling, especially away from the wells. Consequently, rock physics modeling, integrated with the trends from sequence stratigraphy, become useful for interpreting observed seismic amplitudes away from the wells in terms of underlying sedimentological parameters. We illustrate this methodology using a comprehensive dataset from channelized turbidite systems, deposited in minibasin settings in the offshore Equatorial Guinea, West Africa. First, we present a practical recipe for using closed-form expressions of effective medium models to predict seismic velocities in unconsolidated sandstones. We use an effective medium model that combines perfectly rough and smooth grains (the extended Walton model), and use that model to derive coordination number, porosity, and pressure relations for P and S wave velocities from experimental data. Our recipe provides reasonable fits to other experimental and borehole data, and specifically

Geonucleus, the freeware application for managing geological mapping data in GIS

Science.gov (United States)

Albert, Gáspár

2016-04-01

.g. quick logging of field trips). The layout of the GUI has three components: 1) metadata area, 2) general description area with unlimited storing capacity, 3) switchable panels for observations, measurements, photos and notes. The latter includes panels for stratigraphy, structures, fossils, samples, photo uploads and general notes. Details like the sequence and contact type of layers, the parameters of structures and slickensides, name and condition of fossils and purpose of sampling are also available to log (but not compulsorily). It is also a tool for teaching geological mapping, since the available parameters - listed in the app - draws attention to the details, which are to be observed on the field. Reference: Albert G, Csillag G, Fodor L, Zentai L. 2012: Visualisation of Geological Observations on Web 2.0 Based Maps, in: Zentai, L. and Reyes-Nunez, J (eds.): Maps for the Future - Children, Education and Internet, Series: Lecture Notes in Geoinformation and Cartography, Tentative volume 5 - Springer, pp. 165-178.

China organic-rich shale geologic features and special shale gas production issues

Directory of Open Access Journals (Sweden)

Yiwen Ju

2014-06-01

Full Text Available The depositional environment of organic-rich shale and the related tectonic evolution in China are rather different from those in North America. In China, organic-rich shale is not only deposited in marine environment, but also in non-marine environment: marine-continental transitional environment and lacustrine environment. Through analyzing large amount of outcrops and well cores, the geologic features of organic-rich shale, including mineral composition, organic matter richness and type, and lithology stratigraphy, were analyzed, indicating very special characteristics. Meanwhile, the more complex and active tectonic movements in China lead to strong deformation and erosion of organic-rich shale, well-development of fractures and faults, and higher thermal maturity and serious heterogeneity. Co-existence of shale gas, tight sand gas, and coal bed methane (CBM proposes a new topic: whether it is possible to co-produce these gases to reduce cost. Based on the geologic features, the primary production issues of shale gas in China were discussed with suggestions.

Identifikasi Lapisan Geologi Bawah Permukaan Berdasarkan Data Geomagnetik di Sungai Logawa Banyumas

Directory of Open Access Journals (Sweden)

Sukmaji Anom Raharjo

2014-02-01

Full Text Available Identification of geological resources can be done either using surface mapping and cross sectional stratigraphy measurement or geophysical approximation beneath the earth surface. Geomagnetic exploration related to the existing of gold mineral begins with the total magnetic field intensity measurements at 173 locations was scattered in 109.196970 - 109.207580E and 7.448830 - 7.454110S. Interpretation from processing of data obtained four anomalous object, which is defined as fine-medium sandstone (χ= 0.0015 cgs units, coarse sandstone and compact (χ= 0.0035 cgs units, igneous basalt-andesite old Slamet (χ= 0.0085 cgs units, and the complex bedrock (χ= 0.0145 cgs units. The presence of gold mineralization in the rock throughout geomagnetic surveys used to identification of subsurface geological which is interpreted from the processing data that indicated the presence of gold in association with sedimentary (sandstone is often referred to as sediment-hosted.

Stratigraphy and paleohydrology of delta channel deposits, Jezero crater, Mars

Science.gov (United States)

Goudge, Timothy A.; Mohrig, David; Cardenas, Benjamin T.; Hughes, Cory M.; Fassett, Caleb I.

2018-02-01

The Jezero crater open-basin lake contains two well-exposed fluvial sedimentary deposits formed early in martian history. Here, we examine the geometry and architecture of the Jezero western delta fluvial stratigraphy using high-resolution orbital images and digital elevation models (DEMs). The goal of this analysis is to reconstruct the evolution of the delta and associated shoreline position. The delta outcrop contains three distinct classes of fluvial stratigraphy that we interpret, from oldest to youngest, as: (1) point bar strata deposited by repeated flood events in meandering channels; (2) inverted channel-filling deposits formed by avulsive distributary channels; and (3) a valley that incises the deposit. We use DEMs to quantify the geometry of the channel deposits and estimate flow depths of ∼7 m for the meandering channels and ∼2 m for the avulsive distributary channels. Using these estimates, we employ a novel approach for assessing paleohydrology of the formative channels in relative terms. This analysis indicates that the shift from meandering to avulsive distributary channels was associated with an approximately four-fold decrease in the water to sediment discharge ratio. We use observations of the fluvial stratigraphy and channel paleohydrology to propose a model for the evolution of the Jezero western delta. The delta stratigraphy records lake level rise and shoreline transgression associated with approximately continuous filling of the basin, followed by outlet breaching, and eventual erosion of the delta. Our results imply a martian surface environment during the period of delta formation that supplied sufficient surface runoff to fill the Jezero basin without major drops in lake level, but also with discrete flooding events at non-orbital (e.g., annual to decadal) timescales.

The growth of geological structures by repeated earthquakes, 1, conceptual framework

Science.gov (United States)

King, G.C.P.; Stein, R.S.; Rundle, J.B.

1988-01-01

In many places, earthquakes with similar characteristics have been shown to recur. If this is common, then relatively small deformations associated with individual earthquake cycles should accumulate over time to create geological structures. It is shown that existing models developed to describe leveling line changes associated with the seismic cycle can be adapted to explain geological features associated with a fault. In these models an elastic layer containing the fault overlies a viscous half-space with a different density. Fault motion associated with an earthquake results in immediate deformation followed by a long period of readjustment as stresses relax in the viscous layer and isostatic equilibrium is restored. The flexural rigidity of the crust (or the apparent elastic thickness) provides the main control of the width of a structure. The loading due to erosion and deposition of sediment determines the ratio of uplift to subsidence between the two sides of the fault. -Authors

Stratigraphy and dissolution of the Rustler Formation

International Nuclear Information System (INIS)

Bachman, G.O.

1987-01-01

This report describes the physical stratigraphy of the Rustler Formation, because the Waste Isolation Pilot Plant will be constructed in salt beds that underlie this formation. Described are subdivisions of the formations, the major karst features, and a proposed method for the formation of Nash Draw. 2 refs., 2 figs

Global Journal of Geological Sciences

African Journals Online (AJOL)

Global Journal of Geological Sciences is aimed at promoting research in all areas of Geological Sciences including geochemistry, geophysics, engineering geology, hydrogeology, petrology, mineralogy, geochronology, tectonics, mining, structural geology, marine geology, space science etc. Visit the Global Journal Series ...

Log ASCII Standard (LAS) Files for Geophysical Wireline Well Logs and Their Application to Geologic Cross Sections Through the Central Appalachian Basin

Science.gov (United States)

Crangle, Robert D.

2007-01-01

Introduction The U.S. Geological Survey (USGS) uses geophysical wireline well logs for a variety of purposes, including stratigraphic correlation (Hettinger, 2001, Ryder, 2002), petroleum reservoir analyses (Nelson and Bird, 2005), aquifer studies (Balch, 1988), and synthetic seismic profiles (Kulander and Ryder, 2005). Commonly, well logs are easier to visualize, manipulate, and interpret when available in a digital format. In recent geologic cross sections E-E' and D-D', constructed through the central Appalachian basin (Ryder, Swezey, and others, in press; Ryder, Crangle, and others, in press), gamma ray well log traces and lithologic logs were used to correlate key stratigraphic intervals (Fig. 1). The stratigraphy and structure of the cross sections are illustrated through the use of graphical software applications (e.g., Adobe Illustrator). The gamma ray traces were digitized in Neuralog (proprietary software) from paper well logs and converted to a Log ASCII Standard (LAS) format. Once converted, the LAS files were transformed to images through an LAS-reader application (e.g., GeoGraphix Prizm) and then overlain in positions adjacent to well locations, used for stratigraphic control, on each cross section. This report summarizes the procedures used to convert paper logs to a digital LAS format using a third-party software application, Neuralog. Included in this report are LAS files for sixteen wells used in geologic cross section E-E' (Table 1) and thirteen wells used in geologic cross section D-D' (Table 2).

Geology and bedrock engineering

International Nuclear Information System (INIS)

1985-11-01

This book deals with geology of Korea which includes summary, geology in central part and southern part in Korea and characteristic of geology structure, limestone like geology property of limestone, engineered property of limestone, and design and construction case in limestone area. It also introduces engineered property of the cenozoic, clay rock and shale, geologic and engineered property of phyllite and stratum.

Sequence Stratigraphy of the Dakota Sandstone, Eastern San Juan Basin, New Mexico, and its Relationship to Reservoir Compartmentalization; FINAL

International Nuclear Information System (INIS)

Varney, Peter J.

2002-01-01

This research established the Dakota-outcrop sequence stratigraphy in part of the eastern San Juan Basin, New Mexico, and relates reservoir quality lithologies in depositional sequences to structure and reservoir compartmentalization in the South Lindrith Field area. The result was a predictive tool that will help guide further exploration and development

Geology and Volcanology of Kima'Kho Mountain, Northern British Columbia: A Pleistocene Glaciovolcanic Edifice

Science.gov (United States)

Turnbull, M.; Porritt, L. A.; Edwards, B. R.; Russell, K.

2014-12-01

Kima'Kho Mountain is a 1.8 Ma (40Ar/39Ar of 1.82 +/- 40 ka) Pleistocene an alkali-olivine basaltic tuya situated in northern British Columbia. The volcanic edifice rises 460 m from its base and comprises a central vent, dominated by lapilli-tuff and minor pillow lava and dykes; and a surrounding plateau underlain by a sequence of dipping beds of basaltic tuff-breccia and capped by a series of flat-lying, subaerial lava flows. We present a 1:10,000 geological map for Kima'Kho Mountain building on the preliminary work of Ryane et al. (2010). We use the volcanic stratigraphy to explore the implications of three unique features. (1) The central cone comprises massive to crudely-bedded lapilli tuffs containing abundant armoured lapilli - cores of highly-vesicular pyroclasts coated with blocky to cuspate vitric ash. These units suggest an explosive origin from within an ice-enclosed lake, and deposited by wet, dilute pyroclastic surge events. (2) The entire stratigraphic sequence hosts at least two "passage zones" (cf. Jones, 1969); the presence and geometry of these passage zones constrain ice thicknersses at the time of eruption and inform on the englacial lake dynamics. (3) Lastly, our field-based stratigraphic relationships are at odds with the classic tuya model (i.e. an effusive onset to the eruption, forming pillow basalts, followed by explosive activity). Our field mapping suggests an alternative model of tuya architecture, involving a highly-energetic, sustained explosive onset creating a tephra cone that become emergent followed by effusive eruption to create lavas and a subaqueous lava-fed delta. Jones, J. G. Intraglacial volcanoes of the Laugarvatn region, south-west Iceland-I. Geological Society of London Quarterly Journal 124, 197-211 (1969). Ryane, C., Edwards, B. R. & Russell, J. K. The volcanic stratigraphy of Kima'Kho Mountain: A Pleistocene tuya, northwestern British Columbia. Geological Survey of Canada, Current Research 2011-104, 12p, doi:10

Geologic map and upper Paleozoic stratigraphy of the Marble Canyon area, Cottonwood Canyon quadrangle, Death Valley National Park, Inyo County, California

Science.gov (United States)

Stone, Paul; Stevens, Calvin H.; Belasky, Paul; Montañez, Isabel P.; Martin, Lauren G.; Wardlaw, Bruce R.; Sandberg, Charles A.; Wan, Elmira; Olson, Holly A.; Priest, Susan S.

2014-01-01

This geologic map and pamphlet focus on the stratigraphy, depositional history, and paleogeographic significance of upper Paleozoic rocks exposed in the Marble Canyon area in Death Valley National Park, California. Bedrock exposed in this area is composed of Mississippian to lower Permian (Cisuralian) marine sedimentary rocks and the Jurassic Hunter Mountain Quartz Monzonite. These units are overlain by Tertiary and Quaternary nonmarine sedimentary deposits that include a previously unrecognized tuff to which we tentatively assign an age of late middle Miocene (~12 Ma) based on tephrochronologic analysis, in addition to the previously recognized Pliocene tuff of Mesquite Spring. Mississippian and Pennsylvanian rocks in the Marble Canyon area represent deposition on the western continental shelf of North America. Mississippian limestone units in the area (Tin Mountain, Stone Canyon, and Santa Rosa Hills Limestones) accumulated on the outer part of a broad carbonate platform that extended southwest across Nevada into east-central California. Carbonate sedimentation was interrupted by a major eustatic sea-level fall that has been interpreted to record the onset of late Paleozoic glaciation in southern Gondwana. Following a brief period of Late Mississippian clastic sedimentation (Indian Springs Formation), a rise in eustatic sea level led to establishment of a new carbonate platform that covered most of the area previously occupied by the Mississippian platform. The Pennsylvanian Bird Spring Formation at Marble Canyon makes up the outer platform component of ten third-order (1 to 5 m.y. duration) stratigraphic sequences recently defined for the regional platform succession. The regional paleogeography was fundamentally changed by major tectonic activity along the continental margin beginning in middle early Permian time. As a result, the Pennsylvanian carbonate shelf at Marble Canyon subsided and was disconformably overlain by lower Permian units (Osborne Canyon and

Aesthetics-based classification of geological structures in outcrops for geotourism purposes: a tentative proposal

Science.gov (United States)

Mikhailenko, Anna V.; Nazarenko, Olesya V.; Ruban, Dmitry A.; Zayats, Pavel P.

2017-03-01

The current growth in geotourism requires an urgent development of classifications of geological features on the basis of criteria that are relevant to tourist perceptions. It appears that structure-related patterns are especially attractive for geotourists. Consideration of the main criteria by which tourists judge beauty and observations made in the geodiversity hotspot of the Western Caucasus allow us to propose a tentative aesthetics-based classification of geological structures in outcrops, with two classes and four subclasses. It is possible to distinguish between regular and quasi-regular patterns (i.e., striped and lined and contorted patterns) and irregular and complex patterns (paysage and sculptured patterns). Typical examples of each case are found both in the study area and on a global scale. The application of the proposed classification permits to emphasise features of interest to a broad range of tourists. Aesthetics-based (i.e., non-geological) classifications are necessary to take into account visions and attitudes of visitors.

Quantifying small-scale spatio-temporal variability of snow stratigraphy in forests based on high-resolution snow penetrometry

Science.gov (United States)

Teich, M.; Hagenmuller, P.; Bebi, P.; Jenkins, M. J.; Giunta, A. D.; Schneebeli, M.

2017-12-01

Snow stratigraphy, the characteristic layering within a seasonal snowpack, has important implications for snow remote sensing, hydrology and avalanches. Forests modify snowpack properties through interception, wind speed reduction, and changes to the energy balance. The lack of snowpack observations in forests limits our ability to understand the evolution of snow stratigraphy and its spatio-temporal variability as a function of forest structure and to observe snowpack response to changes in forest cover. We examined the snowpack under canopies of a spruce forest in the central Rocky Mountains, USA, using the SnowMicroPen (SMP), a high resolution digital penetrometer. Weekly-repeated penetration force measurements were recorded along 10 m transects every 0.3 m in winter 2015 and bi-weekly along 20 m transects every 0.5 m in 2016 in three study plots beneath canopies of undisturbed, bark beetle-disturbed and harvested forest stands, and an open meadow. To disentangle information about layer hardness and depth variabilities, and to quantitatively compare the different SMP profiles, we applied a matching algorithm to our dataset, which combines several profiles by automatically adjusting their layer thicknesses. We linked spatial and temporal variabilities of penetration force and depth, and thus snow stratigraphy to forest and meteorological conditions. Throughout the season, snow stratigraphy was more heterogeneous in undisturbed but also beneath bark beetle-disturbed forests. In contrast, and despite remaining small diameter trees and woody debris, snow stratigraphy was rather homogenous at the harvested plot. As expected, layering at the non-forested plot varied only slightly over the small spatial extent sampled. At the open and harvested plots, persistent crusts and ice lenses were clearly present in the snowpack, while such hard layers barely occurred beneath undisturbed and disturbed canopies. Due to settling, hardness significantly increased with depth at

Stratigraphy of the type Maastrichtian – a synthesis

NARCIS (Netherlands)

Jagt, J.W.M.; Jagt-Yazykova, E.A.

2012-01-01

A synthesis of the stratigraphy of the Maastrichtian Stage in its extended type area, that is, southern Limburg (the Netherlands), and adjacent Belgian and German territories, is presented with a brief historical overview. Quarrying activities at the large quarry complex of ENCI-HeidelbergCement

Annual review of earth and planetary sciences. Volume 16

International Nuclear Information System (INIS)

Wetherill, G.W.; Albee, A.L.; Stehli, F.G.

1988-01-01

Various papers on earth and planetary science topics are presented. The subjects addressed include: role and status of earth science field work; phase relations of prealuminous granitic rocks and their petrogenetic implications; chondritic meteorites and the solar nebula; volcanic winters; mass wasting on continental margins; earthquake ground motions; ore deposits as guides to geologic history of the earth; geology of high-level nuclear waste disposal; and tectonic evolution of the Caribbean. Also discussed are: the earth's rotation; the geophysics of a restless caldera (Long Valley, California); observations of cometary nuclei; geology of Venus; seismic stratigraphy; in situ-produced cosmogenic isotopes in terrestrial rocks; time variations of the earth's magnetic field; deep slabs, geochemical heterogeneity, and the large-scale structure of mantle convection; early proterozoic assembly and growth of Laurentia; concepts and methods of high-resolution event stratigraphy

Geomorphic Transport Laws and the Statistics of Topography and Stratigraphy

Science.gov (United States)

Schumer, R.; Taloni, A.; Furbish, D. J.

2016-12-01

Geomorphic transport laws take the form of partial differential equations in which sediment motion is a deterministic function of slope. The addition of a noise term, representing unmeasurable, or subgrid scale autogenic forcing, reproduces scaling properties similar to those observed in topography, landforms, and stratigraphy. Here we describe a transport law that generalizes previous equations by permitting transport that is local or non-local in addition to different types of noise. More importantly, we use this transport law to link the character of sediment transport to the statistics of topography and stratigraphy. In particular, we link the origin of the Sadler effect to the evolution of the earth surface via a transport law.

Problems of solidificated radioactive wastes burial into deep geological structures

International Nuclear Information System (INIS)

Kedrovskij, O.L.; Leonov, E.A.; Romadin, N.M.; Shishcits, I.Yu.

1981-01-01

Perspectives are noted of the radioactive wastes burial into deep geopogical structures. For these purposes it has been proposed to investigate severap types of rocks, which do not have intensive gas-generation when beeng heated; salt deposits and clays. Basing on the results of calculations it has been shown that the dimentions of zones of substantial deformations in the case of the high-level radioactive wastes burial to not exceed several hundreds of meters. Conclusion is made that in the case of choosing the proper geotogicat structure for burial and ir the case of inclusion in the structure of the burial site a zone of sanitary alienation, it is possible to isolate wastes safely for all the period of preservation. Preliminary demands have been formulated to geological structures and underground burial sites. As main tasks for optimizatiop of burial sited are considered: determination of necessary types, number and reliability of barriers which ensure isolation of wastes; to make prognoses of the stressed and deformed state of a geological massif on the influence of thermal field; investigation in changes of chemical and physical properties of rocks under heat, radiative and chemical influence; estimation of possible diffusion of radioactivity in a mountin massif; development of a rational mining-thechnological schemes of the burual of wastes of different types. A row of tasks in the farmeworks of this probtem are sotved successfutty. Some resutts are given of the theoretical investigations in determination of zones of distructions of rocks because of heat-load [ru

Morphology, stratigraphy and oxygen isotope composition of fossil glacier ice at Ledyanaya Gora, Northwest Siberia, Russia

International Nuclear Information System (INIS)

Vaikmaee, R.; Michel, F.A.; Solomatin, V.I.

1993-01-01

Studies of the stratigraphy, sedimentology, structure and isotope composition of a buried massive ice body and its encompassing sediments at Ledyanaya Gora in northwestern Siberia demonstrate that the ice is relict glacier ice, probably emplaced during the Early Weichselian. Characteristics of this ice body should serve as a guide for the identification of other relict buried glacier ice bodies in permafrost regions. 31 refs., 9 figs., 2 tabs

Oresajo et al (15).cdr

African Journals Online (AJOL)

Timothy Ademakinwa

2 (2015). SEQUENCE STRATIGRAPHY AND STRUCTURAL ANALYSIS OF THE EMI FIELD,. OFFSHORE ... flooding surfaces, which subdivided the stratigraphic succession within the Emi Field into three depositional sequences. ..... American Association of Petroleum Geologists, ... Africa. U.S. Geological Survey Open-File.

Review of the intrusive, structural and metamorphic history of the Namaqualand geotraverse and environs

International Nuclear Information System (INIS)

Blignault, H.J.; Van Aswegen, G.; Van der Merwe, S.W.

1981-01-01

The Namaqualand excursion is concerned with the geologic strata, stratigraphy and metamorhic history of the Namaqualand geotraverse and its environs. The general aim of the project was to decipher the history and interactions of tectonic, metamorphic and magmatic processes. Isotope dating were used to determine the ages of various rock formations

Mars north polar deposits: stratigraphy, age, and geodynamical response.

Science.gov (United States)

Phillips, Roger J; Zuber, Maria T; Smrekar, Suzanne E; Mellon, Michael T; Head, James W; Tanaka, Kenneth L; Putzig, Nathaniel E; Milkovich, Sarah M; Campbell, Bruce A; Plaut, Jeffrey J; Safaeinili, Ali; Seu, Roberto; Biccari, Daniela; Carter, Lynn M; Picardi, Giovanni; Orosei, Roberto; Mohit, P Surdas; Heggy, Essam; Zurek, Richard W; Egan, Anthony F; Giacomoni, Emanuele; Russo, Federica; Cutigni, Marco; Pettinelli, Elena; Holt, John W; Leuschen, Carl J; Marinangeli, Lucia

2008-05-30

The Shallow Radar (SHARAD) on the Mars Reconnaissance Orbiter has imaged the internal stratigraphy of the north polar layered deposits of Mars. Radar reflections within the deposits reveal a laterally continuous deposition of layers, which typically consist of four packets of finely spaced reflectors separated by homogeneous interpacket regions of nearly pure ice. The packet/interpacket structure can be explained by approximately million-year periodicities in Mars' obliquity or orbital eccentricity. The observed approximately 100-meter maximum deflection of the underlying substrate in response to the ice load implies that the present-day thickness of an equilibrium elastic lithosphere is greater than 300 kilometers. Alternatively, the response to the load may be in a transient state controlled by mantle viscosity. Both scenarios probably require that Mars has a subchondritic abundance of heat-producing elements.

Geology and sequence stratigraphy of undiscovered oil and gas resources in conventional and continuous petroleum systems in the Upper Cretaceous Eagle Ford Group and related strata, U.S. Gulf Coast Region

Science.gov (United States)

Dubiel, Russell F.; Pearson, Ofori N.; Pitman, Janet K.; Pearson, Krystal M.; Kinney, Scott A.

2012-01-01

The U.S. Geological Survey (USGS) recently assessed the technically recoverable undiscovered oil and gas onshore and in State waters of the Gulf Coast region of the United States. The USGS defined three assessment units (AUs) with potential undiscovered conventional and continuous oil and gas resources in Upper Cretaceous (Cenomanian to Turonian) strata of the Eagle Ford Group and correlative rocks. The assessment is based on geologic elements of a total petroleum system, including hydrocarbon source rocks (source rock maturation, hydrocarbon generation and migration), reservoir rocks (sequence stratigraphy and petrophysical properties), and traps (formation, timing, and seals). Conventional oil and gas undiscovered resources are in updip sandstone reservoirs in the Upper Cretaceous Tuscaloosa and Woodbine Formations (or Groups) in Louisiana and Texas, respectively, whereas continuous oil and continuous gas undiscovered resources reside in the middip and downdip Upper Cretaceous Eagle Ford Shale in Texas and the Tuscaloosa marine shale in Louisiana. Conventional resources in the Tuscaloosa and Woodbine are included in the Eagle Ford Updip Sandstone Oil and Gas AU, in an area where the Eagle Ford Shale and Tuscaloosa marine shale display vitrinite reflectance (Ro) values less than 0.6%. The continuous Eagle Ford Shale Oil AU lies generally south of the conventional AU, is primarily updip of the Lower Cretaceous shelf edge, and is defined by thermal maturity values within shales of the Eagle Ford and Tuscaloosa that range from 0.6 to 1.2% Ro. Similarly, the Eagle Ford Shale Gas AU is defined downdip of the shelf edge where source rocks have Ro values greater than 1.2%. For undiscovered oil and gas resources, the USGS assessed means of: 1) 141 million barrels of oil (MMBO), 502 billion cubic feet of natural gas (BCFG), and 4 million barrels of natural gas liquids (MMBNGL) in the Eagle Ford Updip Sandstone Oil and Gas AU; 2) 853 MMBO, 1707 BCFG, and 34 MMBNGL in the

Stratigraphy, sedimentology and bulk organic geochemistry of black ...

Indian Academy of Sciences (India)

Stratigraphy, sedimentology and bulk organic geochemistry of black shales from the Proterozoic. Vindhyan Supergroup (central India). S Banerjee1,∗. , S Dutta. 2. , S Paikaray. 1 and U Mann. 2. 1. Department of Earth Sciences, Indian Institute of Technology Bombay, Powai, Mumbai 400 076, India. 2. Forschungszentrum ...

Geological study for identifying potential aquifer zone in Pakes and Bandung Villages, Konang District, Bangkalan Region

International Nuclear Information System (INIS)

I Gde Sukadana

2010-01-01

Konang District has a problem on fresh water supply particularly in dry season. Two villages in the district, namely Pakes and Konang, are densely populated areas having agriculture activities, so available of sufficient fresh water is necessary. A fresh water source that can be developed in this area is deep groundwater source from potential aquifers. A geological study has been conducted to identify potential aquifer based on lithological aspect and geological structure. According to the regional stratigraphy. the study area consists of Tawun Formation and Ngrayong Formation. They compose of carbonaceous clay stone (the oldest rock unit), carbonaceous clay stone with sandy limestone intercalations, sandy limestone interbed with carbonaceous clay stone, tuff sandstone with clay stone intercalations, and reef limestone (the youngest) respectively. Strike and dip positions of the rocks layers are N110°E/22° - N150°E/26°, located on the south anticline axis with wavy plan to gentle slope of hilly morphology. Among the rock unit, only sandy limestone has fine sand with sub angular in shape and open pack. Qualitatively. this rock has good porosity and permeability and is enables to save and to flow subsurface water. Thus. the sandy limestone is considered as a potential zone for fresh water resources. Whereas, carbonaceous clay stone with clay grain size has low porosity and permeability, so it is potential as a cap rock. (author)

Integrated stratigraphy and paleoenvironmental reconstruction for the Late Cretaceous Danish chalk based on the Stevns-2 core

DEFF Research Database (Denmark)

Boussaha, Myriam; Thibault, Nicolas Rudolph; Stemmerik, Lars

An integrated stratigraphy of the Stevns-2 core located in eastern Denmark is hereby presented based on calcareous nannofossil biostratigraphy and carbon isotope stratigraphy. Carbon and oxygen isotope have been performed on 419 bulk samples. Calcareous nannofossil biostratigraphy has been applied...

Structural geology mapping using PALSAR data in the Bau gold mining district, Sarawak, Malaysia

Science.gov (United States)

Pour, Amin Beiranvand; Hashim, Mazlan

2014-08-01

The application of optical remote sensing data for geological mapping is difficult in the tropical environment. The persistent cloud coverage, dominated vegetation in the landscape and limited bedrock exposures are constraints imposed by the tropical climate. Structural geology investigations that are searching for epithermal or polymetallic vein-type ore deposits can be developed using Synthetic Aperture Radar (SAR) remote sensing data in tropical/sub-tropical regions. The Bau gold mining district in the State of Sarawak, East Malaysia, on the island of Borneo has been selected for this study. The Bau is a gold field similar to Carlin style gold deposits, but gold mineralization at Bau is much more structurally controlled. Geological analyses coupled with the Phased Array type L-band Synthetic Aperture Radar (PALSAR) remote sensing data were used to detect structural elements associated with gold mineralization. The PALSAR data were used to perform lithological-structural mapping of mineralized zones in the study area and surrounding terrain. Structural elements were detected along the SSW to NNE trend of the Tuban fault zone and Tai Parit fault that corresponds to the areas of occurrence of the gold mineralization in the Bau Limestone. Most of quartz-gold bearing veins occur in high-angle faults, fractures and joints within massive units of the Bau Limestone. The results show that four deformation events (D1-D4) in the structures of the Bau district and structurally controlled gold mineralization indicators, including faults, joints and fractures are detectable using PALSAR data at both regional and district scales. The approach used in this study can be more broadly applicable to provide preliminary information for exploration potentially interesting areas of epithermal or polymetallic vein-type mineralization using the PALSAR data in the tropical/sub-tropical regions.

Archaeological recording and chemical stratigraphy applied to contaminated land studies.

Science.gov (United States)

Photos-Jones, Effie; Hall, Allan J

2011-11-15

The method used by archaeologists for excavation and recording of the stratigraphic evidence, within trenches with or without archaeological remains, can potentially be useful to contaminated land consultants (CLCs). The implementation of archaeological practice in contaminated land assessments (CLAs) is not meant to be an exercise in data overkill; neither should it increase costs. Rather, we suggest, that if the excavation and recording, by a trained archaeologist, of the stratigraphy is followed by in-situ chemical characterisation then it is possible that much uncertainty associated with current field sampling practices, may be removed. This is because built into the chemical stratigraphy is the temporal and spatial relationship between different parts of the site reflecting the logic behind the distribution of contamination. An archaeological recording with chemical stratigraphy approach to sampling may possibly provide 'one method fits all' for potentially contaminated land sites (CLSs), just as archaeological characterisation of the stratigraphic record provides 'one method fits all' for all archaeological sites irrespective of period (prehistoric to modern) or type (rural, urban or industrial). We also suggest that there may be practical and financial benefits to be gained by pulling together expertise and resources stemming from different disciplines, not simply at the assessment phase, but also subsequent phases, in contaminated land improvement. Copyright © 2011 Elsevier B.V. All rights reserved.

TWO EXAMPLES FOR IMAGING BURIED GEOLOGICAL BOUNDARIES: SINKHOLE STRUCTURE AND SEYİT HACI FAULT, KARAPINAR, KONYA

Directory of Open Access Journals (Sweden)

Ertan TOKER

2014-12-01

Full Text Available Once anomalies with positive and negative circular closures are assessed together inpotential field maps, the ones which have meaningful geometric structure appear as moredistinguishable. When the edge detection is applied, the preliminary geological modelabout the geological structure may or may not be verified. When it is not verified then it isunderstood that the predicted geological model should be reconsidered and discussedagain. In this study, the edge detection was introduced and the success of the method wastested in an artificial data. Following that, its effect on sinkholes was studied applying themethod on detailed gravity data collected in Karapınar (Konya region. At the same time,this method was applied on data related to active Seyit Hacı Fault zone. It was detectedthat the fault had shown continuity towards SW and these evidences were discussed

Biostratigraphy and sequence stratigraphy of the Sarvak Formation at Fahliyan Anticline (South of Yasuj)

International Nuclear Information System (INIS)

Ahmadi, A.; Vaziri-Moghaddam, A.; Sayrafian, A.; Taheri, A.

2016-01-01

In this study, bio stratigraphy, depositional environment and sequence stratigraphy of the Sarvak Formation at Fahliyan Anticline was studied. 8 species of benthic foraminifera (4 genera) and 8 species of planktonic foraminifera (11 genera) in the study area were recognized. 6 biozones have been recognized by distribution of the foraminifera, which in stratigraphic order are: Favusella washitensis Zone, Orbitolina-Alveolinids Assemblage Zone, Rudist debris Zone, Oligostegina flood Zone, Whiteinella archaeocretacea Zone and Helvetoglobotruncana helvetica Zone. On the basis of these, the age of Albian–Turonian was considered for the Sarvak Formation. Based on petrography and analysis of microfacies features 9 different microfacies types have been recognized, which can be grouped into 3 depositional environments: lagoon, shoal and open marine. The Sarvak Formation represents sedimentation on a carbonate ramp. Sequence stratigraphy analysis led to identification of 4 third-order sequences.

Study on the estimation method of uplift during the late quaternary by using river terraces. 1. Strategy of terrace correlation and a case study on stratigraphy of river terraces

International Nuclear Information System (INIS)

Hataya, Ryuta

2005-01-01

There are a few uplift data during the late Quaternary obtained by using river terraces than those by using marine terraces, because it is difficult to date a river terrace whose age is older than the marine oxygen isotope stage 6. In this paper, at first, we reviewed the terrace correlation method, and we proposed our viewpoint of terrace correlation which is based on relationship between geomorphologic features of terraces and geology that consist of terraces. Next, we did the case study on terrace stratigraphy in the Kawasaki Basin, Miyagi pref., and showed that our method is practical. (author)

Application of thermoluminescence dating on pressed crystalline samples to determine the geological age at some areas in Eastern South, Vietnam

International Nuclear Information System (INIS)

Do Duy Khiem; Luu Anh Tuyen; Phan Trong Phuc; Nguyen Thi Ngoc Hue; Pham Thi Hue; La Ly Nguyen; Ha Quang Hai

2016-01-01

The terrestrial part of eastern margin of the Mekong Basin is formed by outcrop of the pre-Holocen Cenozoic sequence. Almost previous studies concerned in using relative methods in geologic dating at the Mekong Basin, therefore, the ages of its stratigraphy are still unclear. The thermoluminescence (TL) dating was considered as one of the precise methods in geologic dating. In our study, we used TL dating for some areas at Eastern South, Vietnam including Ba Mieu Formation and the Thu Duc Formation at some areas in Dong Nai province and Ho Chi Minh City. This work has been the first application of TL for in geologic dating by a domestic laboratory. Experimental measurements of TL were performed using pressed crystalline quartz specimens from sediment samples. The results show that the Ba Mieu Formation was deposited about 238±22 ka and the Thu Duc Formation was deposited about 199±21 ka. (author)

A Geological Model for the Evolution of Early Continents (Invited)

Science.gov (United States)

Rey, P. F.; Coltice, N.; Flament, N. E.; Thébaud, N.

2013-12-01

Geochemical probing of ancient sediments (REE in black shales, strontium composition of carbonates, oxygen isotopes in zircons...) suggests that continents were a late Archean addition at Earth's surface. Yet, geochemical probing of ancient basalts reveals that they were extracted from a mantle depleted of its crustal elements early in the Archean. Considerations on surface geology, the early Earth hypsometry and the rheology and density structure of Archean continents can help solve this paradox. Surface geology: The surface geology of Archean cratons is characterized by thick continental flood basalts (CFBs, including greenstones) emplaced on felsic crusts dominated by Trondhjemite-Tonalite-Granodiorite (TTG) granitoids. This simple geology is peculiar because i/ most CFBs were emplaced below sea level, ii/ after their emplacement, CFBs were deformed into relatively narrow, curviplanar belts (greenstone basins) wrapping around migmatitic TTG domes, and iii/ Archean greenstone belts are richly endowed with gold and other metals deposits. Flat Earth hypothesis: From considerations on early Earth continental geotherm and density structure, Rey and Coltice (2008) propose that, because of the increased ability of the lithosphere to flow laterally, orogenic processes in the Archean produced only subdued topography (geology, can be proposed: 1/ Continents appeared at Earth's surface at an early stage during the Hadean/Archean. However, because they were i/ covered by continental flood basalts, ii/ below sea level, and iii/ deprived of modern-style mountain belts and orogenic plateaux, early felsic

Geological development and uranium and thorium evolutions in volcanic basin No.460

International Nuclear Information System (INIS)

Zhou Dean.

1989-01-01

On the basis of summarizing the geological features and the developmental history of tectono-magmatic activity, the uranium and thorium evolutional rules of rocks in different times are studied. It is suggested that the uranium and thorium increments caused by potassic migmatization of late Archean basement rocks in this area is the material base which affected the subsequent evolution of the cover of volcanic rocks and uranium mineralization. The Upper Jurassic acid volcanic cover belonging to crustal remelting origin constituted the favorable stratigraphic background for uranium mineralization in this area due to its wide distribution, large thickness, various rock associations and lithological sequences, as well as high content of uranium and thorium. During the late Yanshanian stage acid subvolanic rocks or small intrusions with high uranium intruded along the regional fractures are the decisive factors for the emplacement of uranium mineralization in this area, which othen became the favorable wall rocks for preserving ores itself. During the late stage the hydrothermal uranium mineralization was the main geological process from which uranium and thorium in stratigraphy and terrain were finally separated

Late Carboniferous to Late Permian carbon isotope stratigraphy

DEFF Research Database (Denmark)

Buggisch, Werner; Krainer, Karl; Schaffhauser, Maria

2015-01-01

An integrated study of the litho-, bio-, and isotope stratigraphy of carbonates in the Southern Alps was undertaken in order to better constrain δ13C variations during the Late Carboniferous to Late Permian. The presented high resolution isotope curves are based on 1299 δ13Ccarb and 396 δ13Corg...

Geology and stratigraphy of the San Lorenzo Tezonco deep well and its correlation to surrounding ranges, Mexico Basin

Science.gov (United States)

Arce, J. L.; Layer, P. W.; Morales-Casique, E.; Benowitz, J.

2014-12-01

The San Lorenzo Tezonco deep well stratigraphy records intense episodic volcanic activity in the Mexico Basin and surroundings during the past 20 Ma. The 2008-m deep lithological column is dominated by volcanic material, either as lava flows or pyroclastic deposits (97%), and only the upper most 70 m are composed of lacustrine deposits (3%). Based on geochronology and geochemistry, the lower part of the drill core is represented by rocks correlating to the Tepoztlán Formation (876-2008 m deep) that vary in composition from basaltic-andesite to rhyolite, and ages ranging from 13 to 21.2 Ma. On the surface this formation outcrops near the towns of Malinalco and Tepoztlán, ~43 km south of the deep well. Between depths of 581 and 875 m, volcanic rocks were recovered and are interpreted as lavas from the Sierra de las Cruces that vary in composition from andesite to dacite and range in age from 0.9 Ma to 5 Ma. Additionally, we documented rocks belonging to the Xochitepec Formation, outcropping around Xochimilco, in the Mexico City, with ages ranging from 1.2 and 1.7 Ma, in contrast with the Oligocene age proposed in previous works for these rocks. These new ages plus the chemical composition data, allow us to correlate the Xochitepec rocks with Sierra de las Cruces. Upward in the drill core (510-580 m) there are andesitic rocks that correlate with the 0.25 Ma Cerro de la Estrella volcanic center. The last volcanic package found in the well is correlated to the Santa Catarina basaltic andesites (70-120 m) that are younger than 0.25 Ma, and probably Holocene. Lacustrine deposits crown the stratigraphic column of the drill core with ages probably younger than 34 ka. The San Lorenzo Tezonco well is in a graben-like structure that was filled with more than 1900 m of volcanic products, suggesting that volcanism were intense in the Miocene to the Recent, and the south drainage of the Mexico Basin was closed probably in the early Pleistocene.

Reading and Abstracting Journal Articles in Sedimentology and Stratigraphy.

Science.gov (United States)

Conrad, Susan Howes

1991-01-01

An assignment centered on reading journal articles and writing abstracts is an effective way to improve student reading and writing skills in sedimentology and stratigraphy laboratories. Each student reads two articles and writes informative abstracts from the author's point of view. (PR)

Modelling of cyclical stratigraphy using Markov chains

Energy Technology Data Exchange (ETDEWEB)

Kulatilake, P.H.S.W.

1987-07-01

State-of-the-art on modelling of cyclical stratigraphy using first-order Markov chains is reviewed. Shortcomings of the presently available procedures are identified. A procedure which eliminates all the identified shortcomings is presented. Required statistical tests to perform this modelling are given in detail. An example (the Oficina formation in eastern Venezuela) is given to illustrate the presented procedure. 12 refs., 3 tabs. 1 fig.

Sediment transport processes and their resulting stratigraphy: informing science and society

Science.gov (United States)

Nittrouer, J. A.

2013-12-01

Sediment transport physically shapes planetary surfaces by producing patterns of erosion and deposition, with the relative magnitudes of geomorphic actions varying according to environmental conditions. Where sediment fills accommodation space and generates accumulation, a stratigraphic archive develops that potentially harbors a trove of information documenting dynamic conditions during the periods of sediment production, transport and deposition. By investigating the stratigraphic record, it is possible to describe changes in surface environments, as well as hypothesize about the development of regional tectonic and climate regimes. Ultimately, information contained within the stratigraphic record is critical for evaluating the geological history of terrestrial planets. The enigma of stratigraphy, however, is that sediment deposition is finicky, there is no uninterrupted record, and while deposits may reflect only a brief temporal window, they may still be used to infer about conditions that encompass much longer periods of time. Consider a case where meter-scale dune foresets, deposited in a matter of minutes to hours, are in contact with sediments above and below that reflect entirely different depositional circumstances and are separated in time by a hiatus of thousands or perhaps millions of years. To effectively unlock the scientific trove bound in stratigraphy, it is first necessary to identify where such unconformities exist and the conditions that lead to their development. This challenge is made much simpler through scientific advances in understanding sediment transport processes -- the examination of how fluid and solids interact under modern conditions -- because this is precisely where sediment patterns first emerge to produce accumulation that builds a stratigraphic record. By advancing an understanding of process-based sedimentology, it is possible to enhance diagnostic evaluations of the stratigraphic record. Fortunately, over the past several

Stratigraphy and erosional landforms of layered deposits in Valles Marineris, Mars

Science.gov (United States)

Komatsu, G.; Geissler, P. E.; Strom, R. G.; Singer, R. B.

1993-01-01

Satellite imagery is used to identify stratigraphy and erosional landforms of 13 layered deposits in the Valles Marineris region of Mars (occurring, specifically, in Gangis, Juventae, Hebes, Ophir-Candor, Melas, and Capri-Eos Chasmata), based on albedo and erosional styles. Results of stratigraphic correlations show that the stratigraphy of layered deposits in the Hebes, Juventae, and Gangis Chasmata are not well correlated, indicating that at least these chasmata had isolated depositional environments resulting in different stratigraphic sequences. On the other hand, the layered deposits in Ophir-Candor and Melas Chasmata appear to have been connected in each chasma. Some of the layered deposits display complexities which indicate changes in space and time in the dominant source materials.

Approaches for the accurate definition of geological time boundaries

Science.gov (United States)

Schaltegger, Urs; Baresel, Björn; Ovtcharova, Maria; Goudemand, Nicolas; Bucher, Hugo

2015-04-01

Which strategies lead to the most precise and accurate date of a given geological boundary? Geological units are usually defined by the occurrence of characteristic taxa and hence boundaries between these geological units correspond to dramatic faunal and/or floral turnovers and they are primarily defined using first or last occurrences of index species, or ideally by the separation interval between two consecutive, characteristic associations of fossil taxa. These boundaries need to be defined in a way that enables their worldwide recognition and correlation across different stratigraphic successions, using tools as different as bio-, magneto-, and chemo-stratigraphy, and astrochronology. Sedimentary sequences can be dated in numerical terms by applying high-precision chemical-abrasion, isotope-dilution, thermal-ionization mass spectrometry (CA-ID-TIMS) U-Pb age determination to zircon (ZrSiO4) in intercalated volcanic ashes. But, though volcanic activity is common in geological history, ashes are not necessarily close to the boundary we would like to date precisely and accurately. In addition, U-Pb zircon data sets may be very complex and difficult to interpret in terms of the age of ash deposition. To overcome these difficulties we use a multi-proxy approach we applied to the precise and accurate dating of the Permo-Triassic and Early-Middle Triassic boundaries in South China. a) Dense sampling of ashes across the critical time interval and a sufficiently large number of analysed zircons per ash sample can guarantee the recognition of all system complexities. Geochronological datasets from U-Pb dating of volcanic zircon may indeed combine effects of i) post-crystallization Pb loss from percolation of hydrothermal fluids (even using chemical abrasion), with ii) age dispersion from prolonged residence of earlier crystallized zircon in the magmatic system. As a result, U-Pb dates of individual zircons are both apparently younger and older than the depositional age

Geological and structural interpretation of Peninsular Malaysia by marine and aeromagnetic data: Some preliminary results

Science.gov (United States)

Bahrudin, Nurul Fairuz Diyana Binti; Hamzah, Umar

2016-11-01

Magnetic data were processed to interpret the geology of Peninsular Malaysia especially in delineating the igneous bodies and structural lineament trends by potential field geophysical method. A total of about 32000 magnetic intensity data were obtained from Earth Magnetic Anomaly Grid (EMAG2) covering an area of East Sumatra to part of South China Sea within 99° E to 105° E Longitude and 1° N to 7°N Latitude. These data were used in several processing stages in generating the total magnetic intensity (TMI), reduce to equator (RTE), total horizontal derivative (THD) and total vertical derivative (TVD). Values of the possible surface and subsurface magnetic sources associated to the geological features of the study area. The magnetic properties are normally corresponding to features like igneous bodies and faults structures. The anomalies obtained were then compared to the geological features of the area. In general, the high magnetic anomalies of the TMI-RTE are closely matched with major igneous intrusion of Peninsular Malaysia such as the Main Range, Eastern Belt and the Mersing-Johor Bahru stretch. More dense lineaments of magnetic structures were observed in the THD and TVD results indicating the presence of more deep and shallow magnetic rich geological features. The positions of Bukit Tinggi, Mersing and Lepar faults are perfectly matched with the magnetic highs while the presence of Lebir and Bok Bak faults are not clearly observed in the magnetic results. The high magnetic values of igneous bodies may have concealed and obscured the magnetic values representing these faults.

Stratigraphy of Karaburun Peninsula

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Burhan Erdoğan

1990-06-01

Full Text Available In the Karaburun peninsula, a tectonic bell with a thick Mesozoic succession is located bordering the Izmir-Ankara zone on its western side. In the stratigraphic column of the Karaburun belt, the oldest unit is the Lower and Middle Carboniferous Alandere formation consisting dominantly of fossiliferous limestones. Lower Triassic rocks rest directly above this unit and Upper Carboniferous and Permian sections are missing. The Lower Triassic is represented by rock units showing facies changes in short distances along vertical and horizontal directions. In this part of the section, the Karareis and Gerence formations are differentiated which are collectively named as the Denizgiren group. The Karareis formation is composed of intercalations of sandstones, bedded-black cherts, pelagic limestones and mafic volcanics, whereas the Gerence formation composed dominantly of ammonitic red limestones, thinly-bedded gray limestones, and cherty limestones. The Karareis and Gerence formations grade laterally into each other and range in age from Scythian to Late Anisian. The Camiboğazı formation resting with a gradational contact on each of these units consists of massive limestones with reefal facies in places and yields an age of Ladinian-Camian. The Güvercinlik formation lies conformably above the Camiboğazı formation and consists of algal stromatolites, megalodon-bearing limestones, and quartzitic sandstone intervals. This unit ranges in age from Norian-Rheatian. The Nohutalan formation which is dominantly represented by thick-bedded neritic limestones overlies the Güvercinlik formation gradationally and yields an age ranging from Liassic to Albian. This unit appears to be lithologically continuous in the field without any indications of a break in the stratigraphic or structural record, however, the Dogger age has not been determined which may probably indicate a presence of a hiatus. Above this Mesozoic comprehensive succession with an age

Geological site characterization for the proposed Mixed Waste Disposal Facility, Los Alamos National Laboratory

International Nuclear Information System (INIS)

Reneau, S.L.; Raymond, R. Jr.

1995-12-01

This report presents the results of geological site characterization studies conducted from 1992 to 1994 on Pajarito Mesa for a proposed Los Alamos National Laboratory Mixed Waste Disposal Facility (MWDF). The MWDF is being designed to receive mixed waste (waste containing both hazardous and radioactive components) generated during Environmental Restoration Project cleanup activities at Los Alamos. As of 1995, there is no Resource Conservation and Recovery Act (RCRA) permitted disposal site for mixed waste at the Laboratory, and construction of the MWDF would provide an alternative to transport of this material to an off-site location. A 2.5 km long part of Pajarito Mesa was originally considered for the MWDF, extending from an elevation of about 2150 to 2225 m (7060 to 7300 ft) in Technical Areas (TAs) 15, 36, and 67 in the central part of the Laboratory, and planning was later concentrated on the western area in TA-67. The mesa top lies about 60 to 75 m (200 to 250 ft) above the floor of Pajarito Canyon on the north, and about 30 m (100 ft) above the floor of Threemile Canyon on the south. The main aquifer used as a water supply for the Laboratory and for Los Alamos County lies at an estimated depth of about 335 m (1100 ft) below the mesa. The chapters of this report focus on surface and near-surface geological studies that provide a basic framework for siting of the MWDF and for conducting future performance assessments, including fulfillment of specific regulatory requirements. This work includes detailed studies of the stratigraphy, mineralogy, and chemistry of the bedrock at Pajarito Mesa by Broxton and others, studies of the geological structure and of mesa-top soils and surficial deposits by Reneau and others, geologic mapping and studies of fracture characteristics by Vaniman and Chipera, and studies of potential landsliding and rockfall along the mesa-edge by Reneau

Geological site characterization for the proposed Mixed Waste Disposal Facility, Los Alamos National Laboratory

Energy Technology Data Exchange (ETDEWEB)

Reneau, S.L.; Raymond, R. Jr. [eds.

1995-12-01

This report presents the results of geological site characterization studies conducted from 1992 to 1994 on Pajarito Mesa for a proposed Los Alamos National Laboratory Mixed Waste Disposal Facility (MWDF). The MWDF is being designed to receive mixed waste (waste containing both hazardous and radioactive components) generated during Environmental Restoration Project cleanup activities at Los Alamos. As of 1995, there is no Resource Conservation and Recovery Act (RCRA) permitted disposal site for mixed waste at the Laboratory, and construction of the MWDF would provide an alternative to transport of this material to an off-site location. A 2.5 km long part of Pajarito Mesa was originally considered for the MWDF, extending from an elevation of about 2150 to 2225 m (7060 to 7300 ft) in Technical Areas (TAs) 15, 36, and 67 in the central part of the Laboratory, and planning was later concentrated on the western area in TA-67. The mesa top lies about 60 to 75 m (200 to 250 ft) above the floor of Pajarito Canyon on the north, and about 30 m (100 ft) above the floor of Threemile Canyon on the south. The main aquifer used as a water supply for the Laboratory and for Los Alamos County lies at an estimated depth of about 335 m (1100 ft) below the mesa. The chapters of this report focus on surface and near-surface geological studies that provide a basic framework for siting of the MWDF and for conducting future performance assessments, including fulfillment of specific regulatory requirements. This work includes detailed studies of the stratigraphy, mineralogy, and chemistry of the bedrock at Pajarito Mesa by Broxton and others, studies of the geological structure and of mesa-top soils and surficial deposits by Reneau and others, geologic mapping and studies of fracture characteristics by Vaniman and Chipera, and studies of potential landsliding and rockfall along the mesa-edge by Reneau.

Reflection of block neotectonics in geological structure of paleogene strata of Chornobyl exclusion zone

International Nuclear Information System (INIS)

Skvortsov, V.V.; Oleksandrova, N.V.; Khodorovs'kij, A.Ya.

2014-01-01

Neotectonic block differentiation of Chernobyl Exclusion zone area was fixed by the results of the geological and structure analysis of paleogene strata in complex with the space survey data interpretation. Structural plan of the latest tectonic movements had a block character; it was shown by the fracture systems, which represent the components of known regional tectonic zones of various trends and are found in the features of phanerozoic rock mass structure. The territory under study is divided into two parts - the northern one, where in the neotectonic movements are generally more intensive with manifestation practically all over the fracture zones, and the southern part, where in the newest breaks belong mainly to submeridional also to south-western regional fracture zones. The southern part of the Exclusion zone, as a whole, holds the greatest promise by comparison with the northern one in the view of neotectonic criteria regarding the geological repository siting for radioactive waste disposal

Landslides Zonation Hazard: relation between geological structures and landslides occurrence in hilly tropical regions of Brazil

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RODRIGO I. CERRI

2017-08-01

Full Text Available ABSTRACT This paper presents a new approach of landslides zonation hazard studies, based on an integrated study of structural data along with geomorphological and external factors, in a hilly regions of Brazil, covered by a tropical humid rain-forest, called Serra do Mar. The Serra do Mar consists of a hilly region along the east coast of Brazil, with high slopes and many geological structures in a gneiss - migmatitic terrain. In contrast to traditional approaches, this method proposes that structural data (foliation, fractures and bedding planes and its relation with the slope geometry, is important to be consider in the landslide zonation hazard, along with declivity, relative relief, soil and rock properties, land use and vegetation cover and hydrogeological and climate factors. Results show that slopes with high hazard have the same dip direction of geological structures. Landslide zonation hazard using structural data contributes to a better understanding of how these structures, preserved in tropical residual soils, influence on slope stability and generates landslides.

Landslides Zonation Hazard: relation between geological structures and landslides occurrence in hilly tropical regions of Brazil.

Science.gov (United States)

Cerri, Rodrigo I; Reis, Fábio A G V; Gramani, Marcelo F; Giordano, Lucilia C; Zaine, José Eduardo

2017-01-01

This paper presents a new approach of landslides zonation hazard studies, based on an integrated study of structural data along with geomorphological and external factors, in a hilly regions of Brazil, covered by a tropical humid rain-forest, called Serra do Mar. The Serra do Mar consists of a hilly region along the east coast of Brazil, with high slopes and many geological structures in a gneiss - migmatitic terrain. In contrast to traditional approaches, this method proposes that structural data (foliation, fractures and bedding planes) and its relation with the slope geometry, is important to be consider in the landslide zonation hazard, along with declivity, relative relief, soil and rock properties, land use and vegetation cover and hydrogeological and climate factors. Results show that slopes with high hazard have the same dip direction of geological structures. Landslide zonation hazard using structural data contributes to a better understanding of how these structures, preserved in tropical residual soils, influence on slope stability and generates landslides.

Improvement of geological subsurface structure models for Kanto area, Japan, based on records of microtremor array and earthquake observations

Science.gov (United States)

Wakai, A.; Senna, S.; Jin, K.; Cho, I.; Matsuyama, H.; Fujiwara, H.

2017-12-01

To estimate damage caused by strong ground motions from a large earthquake, it is important to accurately evaluate broadband ground-motion characteristics in wide area. For realizing that, it is one of the important issues to model detailed subsurface structure from top surface of seismic bedrock to ground surface.Here, we focus on Kanto area, including Tokyo, where there are thicker sedimentary layers. We, first, have ever collected deep bore-hole data, soil physical properties obtained by some geophysical explorations, geological information and existing models for deep ground from top surface of seismic bedrock to that of engineering bedrock, and have collected a great number of bore-hole data and surficial geological ones for shallow ground from top surface of engineering bedrock to ground surface. Using them, we modeled initial geological subsurface structure for each of deep ground and shallow one. By connecting them appropriately, we constructed initial geological subsurface structure models from top surface of seismic bedrock to ground surface.In this study, we first collected a lot of records obtained by dense microtremor observations and earthquake ones in the whole Kanto area. About microtremor observations, we conducted measurements from large array with the size of hundreds of meters to miniature array with the size of 60 centimeters to cover both of deep ground and shallow one. And then, using ground motion characteristics such as disperse curves and H/V(R/V) spectral ratios obtained from these records, the initial geological subsurface structure models were improved in terms of velocity structure from top surface of seismic bedrock to ground surface in the area.We will report outlines on microtremor array observations, analysis methods and improved subsurface structure models.

Geological evidence of tsunamis and earthquakes at the Eastern Hellenic Arc: correlation with historical seismicity in the eastern Mediterranean Sea

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Gerassimos Papadopoulos

2012-12-01

Full Text Available Sedimentary stratigraphy determined by trenching in Dalaman, south-western Turkey, revealed three sand layers at a distance of approximately 240 m from the shoreline and at elevations of +0.30, +0.55 and +0.90 cm. Storm surge action does not explain the features of these deposits that show instead typical characteristics of tsunami deposition. The sand layers correlate with historical tsunamis generated by large earthquakes which ruptured the eastern Hellenic Arc and Trench in 1303, 1481 and 1741. Accelerator mass spectrometry 14C dating of a wood sample from layer II indicated deposition in AD 1473±46, which fits the 1481 event. From an estimated average alluvium deposition rate of approximately 0.13 cm/year, layers I and III were dated at 1322 and 1724, which may represent the large 1303 and 1741 tsunamis. The geological record of the 1303 key event is very poor; therefore, sand layer I perhaps represents an important geological signature of the 1303 tsunami. However, the strong tsunami reported to have been generated by the 1609 earthquake is missing from Dalaman stratigraphy: this underlines the sensitivity of tsunami geological signatures to various local factors. The 1303 earthquake ruptured the trench between the islands of Crete and Rhodes. For the earthquakes of 1481, 1609 and 1741 we suggested that they were very likely generated in the Rhodes Abyssal Plain where sea depths of up to approximately 4200 m, together with the thrust component of seismotectonics, favor tsunami generation. Sand dykes directed upwards from layer I to layer II indicated that the 1481 earthquake triggered liquefaction of sand layer I. The results substantially widen our knowledge about the historical earthquake and tsunami activity in the eastern Mediterranean basin.

Author Details

African Journals Online (AJOL)

Konka, Bheemalingeswara. Vol 8, No 1 (2016) - Articles A preliminary Geological and Generalized Stratigraphy of Western Margin of Northern Afar Depression, Dallol Area, Northern Ethiopia Abstract PDF · Vol 9, No 2 (2017) - Articles Hydrothermal gold mineralization and structural controls near May Hibey, Northwestern ...

Effects of Faulted Stratigraphy on Saturated Zone Flow Beneath Yucca Mountain, Nevada

International Nuclear Information System (INIS)

Cohen, Andrew J.B.; Oldenburg, Curtis M.

1999-01-01

The S 4 Z Model (''sub-site-scale saturated zone'') is a 3-D TOUGH2 model that was developed to study the saturated zone (SZ) at Yucca Mountain, Nevada, and to aid in the design and analysis of hydrologic tests. Yucca Mountain is the proposed site for a nuclear waste repository for the United States. The model covers an area of approximately 100 km 2 around Yucca Mountain, as shown in Figure 1. The proposed repository is located in the unsaturated zone, immediately above the area of equidimensional gridblocks east of Solitario Canyon fault, which defines the crest of Yucca Mountain. The finely discretized region near the center of the domain corresponds to the area near a cluster of boreholes used for hydraulic and tracer testing. This discretization facilitates simulation of tests conducted there. The hydrogeologic structure beneath the mountain is comprised of dipping geologic units of variable thickness which are offset by faults. One of the primary objectives of the S 4 Z modeling effort is to study the potential effects of the faulted structure on flow. Therefore, replication of the geologic structure in the model mesh is necessary. This paper summarizes (1) the mesh discretization used to capture the faulted geologic structure, and (2) a model simulation that illustrates the significance of the geologic structure on SZ flow and the resulting macrodispersion

Stratigraphic and structural framework of Yucca Mountain, Nevada

International Nuclear Information System (INIS)

Spengler, R.W.; Fox, K.F. Jr.

1988-01-01

Yucca Mountain is located within the southwestern Nevada volcanic field, ∼140 km northwest of Las Vegas, Nevada, and 50 km northeast of Death Valley, California. The mountain consist of a series of long, linear, north-trending volcanic ridges that approach an 1800-m maximum elevation near The Prow. The broad intermontane alluviated valleys of Crater Flat, the Amargosa Desert, and Jackass Flats, averaging 800 to 1100 m in elevation, form the western, southern, and eastern margins of Yucca Mountain, respectively. North of The Prow, Yucca Mountain merges with other volcanic highlands that flank the southern rim of the Timber Mountain-Oasis Valley caldera complex. The stratigraphy and structure of the area are discussed. Future geologic studies will attempt to determine if faults extend beneath Yucca Mountain, and, if present, their potential effects on the hydrologic and tectonic regimes

3D Geological modelling of the Monfrague synform: a value added to the geologic heritage of the National Park

International Nuclear Information System (INIS)

Gumiel, P.; Arias, M.; Monteserin, V.; Segura, M.

2010-01-01

3D geological modelling of a tectonic structure called the Monfrague synform has been carried out to obtain a better insight into the geometry of this folding structure. It is a kilometric variscan WNW-ESE trending fold verging towards north and made up by a Palaeozoic sequence (Ordovician-Silurian).This structure with its lithology make up the morphology and the relief of the Park. The Monfrague synform is an asymmetrical folding structure showing southern limb dipping steeply to the south (reverse limb) what is well observed in the Armorican Quartzite at the Salto del Gitano. However, northern limb dips gently (less than 40 degree centigrade) to the south (normal limb). 3D geological modelling has been built on the basis of the geological knowledge and the structural interpretation, using 3D GeoModeller. (www.geomodeller.com). In this software, lithological units are described by a stratigraphic pile. A major original feature of this software is that the 3D description of the geological space is achieved through a potential field formulation in which geological boundaries are isopotential surfaces, and their dips are represented by gradients of the potential. Finally, it is emphasized the idea that a 3D geologic model of these characteristics, with its three-dimensional representation, together with suitable geological sections that clarify the structure in depth, represents a value added to the Geologic Heritage of the National Park and besides it supposes an interesting academic exercise which have a great didactic value. (Author)

Effect of explicit representation of detailed stratigraphy on brine and gas flow at the Waste Isolation Pilot Plant

International Nuclear Information System (INIS)

Christian-Frear, T.L.; Webb, S.W.

1996-04-01

Stratigraphic units of the Salado Formation at the Waste Isolation Pilot Plant (WIPP) disposal room horizon includes various layers of halite, polyhalitic halite, argillaceous halite, clay, and anhydrite. Current models, including those used in the WIPP Performance Assessment calculations, employ a ''composite stratigraphy'' approach in modeling. This study was initiated to evaluate the impact that an explicit representation of detailed stratigraphy around the repository may have on fluid flow compared to the simplified ''composite stratigraphy'' models currently employed. Sensitivity of model results to intrinsic permeability anisotropy, interbed fracturing, two-phase characteristic curves, and gas-generation rates were studied. The results of this study indicate that explicit representation of the stratigraphy maintains higher pressures and does not allow as much fluid to leave the disposal room as compared to the ''composite stratigraphy'' approach. However, the differences are relatively small. Gas migration distances are also different between the two approaches. However, for the two cases in which explicit layering results were considerably different than the composite model (anisotropic and vapor-limited), the gas-migration distances for both models were negligible. For the cases in which gas migration distances were considerable, van Genuchten/Parker and interbed fracture, the differences between the two models were fairly insignificant. Overall, this study suggests that explicit representation of the stratigraphy in the WIPP PA models is not required for the parameter variations modeled if ''global quantities'' (e.g., disposal room pressures, net brine and gas flux into and out of disposal rooms) are the only concern

Effect of explicit representation of detailed stratigraphy on brine and gas flow at the Waste Isolation Pilot Plant

Energy Technology Data Exchange (ETDEWEB)

Christian-Frear, T.L.; Webb, S.W. [Sandia National Labs., Albuquerque, NM (United States). Geohydrology Dept.

1996-04-01

Stratigraphic units of the Salado Formation at the Waste Isolation Pilot Plant (WIPP) disposal room horizon includes various layers of halite, polyhalitic halite, argillaceous halite, clay, and anhydrite. Current models, including those used in the WIPP Performance Assessment calculations, employ a ``composite stratigraphy`` approach in modeling. This study was initiated to evaluate the impact that an explicit representation of detailed stratigraphy around the repository may have on fluid flow compared to the simplified ``composite stratigraphy`` models currently employed. Sensitivity of model results to intrinsic permeability anisotropy, interbed fracturing, two-phase characteristic curves, and gas-generation rates were studied. The results of this study indicate that explicit representation of the stratigraphy maintains higher pressures and does not allow as much fluid to leave the disposal room as compared to the ``composite stratigraphy`` approach. However, the differences are relatively small. Gas migration distances are also different between the two approaches. However, for the two cases in which explicit layering results were considerably different than the composite model (anisotropic and vapor-limited), the gas-migration distances for both models were negligible. For the cases in which gas migration distances were considerable, van Genuchten/Parker and interbed fracture, the differences between the two models were fairly insignificant. Overall, this study suggests that explicit representation of the stratigraphy in the WIPP PA models is not required for the parameter variations modeled if ``global quantities`` (e.g., disposal room pressures, net brine and gas flux into and out of disposal rooms) are the only concern.

Subsidence and Rebound in California's Central Valley: Effects of Pumping, Geology, and Precipitation

Science.gov (United States)

Farr, T. G.; Fairbanks, A.

2017-12-01

Recent rains in California caused a pause, and even a reversal in some areas, of the subsidence that has plagued the Central Valley for decades. The 3 main drivers of surface deformation in the Central Valley are: Subsurface hydro-geology, precipitation and surface water deliveries, and groundwater pumping. While the geology is relatively fixed in time, water inputs and outputs vary greatly both in time and space. And while subsurface geology and water inputs are reasonably well-known, information about groundwater pumping amounts and rates is virtually non-existent in California. We have derived regional maps of surface deformation in the region for the period 2006 - present which allow reconstruction of seasonal and long-term changes. In order to understand the spatial and temporal patterns of subsidence and rebound in the Central Valley, we have been compiling information on the geology and water inputs and have attempted to infer pumping rates using maps of fallowed fields and published pumping information derived from hydrological models. In addition, the spatial and temporal patterns of hydraulic head as measured in wells across the region allow us to infer the spatial and temporal patterns of groundwater pumping and recharge more directly. A better understanding of how different areas (overlying different stratigraphy) of the Central Valley respond to water inputs and outputs will allow a predictive capability, potentially defining sustainable pumping rates related to water inputs. * work performed under contract to NASA and the CA Dept. of Water Resources

Hydrogeological Properties of Geological Elements in Geological Model around KURT

Energy Technology Data Exchange (ETDEWEB)

Park, Kyung Woo; Kim, Kyung Soo; Koh, Yong Kwon; Choi, Jong Won [Korea Atomic Energy Institue, Daejeon (Korea, Republic of)

2012-09-15

To develop site characterization technologies for a radioactive waste disposal research in KAERI, the geological and hydrogeological investigations have been carried out since 1997. In 2006, the KURT (KAERI Underground Research Tunnel) was constructed to study a solute migration, a microbiology and an engineered barrier system as well as deeply to understand geological environments in in-situ condition. This study is performed as one of the site characterization works around KURT. Several investigations such as a lineament analysis, a borehole/tunnel survey, a geophyscial survey and logging in borehole, were used to construct the geological model. As a result, the geological model is constructed, which includes the lithological model and geo-structural model in this study. Moreover, from the results of the in-situ hydraulic tests, the hydrogeological properties of elements in geological model were evaluated.

Hydrogeological Properties of Geological Elements in Geological Model around KURT

International Nuclear Information System (INIS)

Park, Kyung Woo; Kim, Kyung Soo; Koh, Yong Kwon; Choi, Jong Won

2012-01-01

To develop site characterization technologies for a radioactive waste disposal research in KAERI, the geological and hydrogeological investigations have been carried out since 1997. In 2006, the KURT (KAERI Underground Research Tunnel) was constructed to study a solute migration, a microbiology and an engineered barrier system as well as deeply to understand geological environments in in-situ condition. This study is performed as one of the site characterization works around KURT. Several investigations such as a lineament analysis, a borehole/tunnel survey, a geophyscial survey and logging in borehole, were used to construct the geological model. As a result, the geological model is constructed, which includes the lithological model and geo-structural model in this study. Moreover, from the results of the in-situ hydraulic tests, the hydrogeological properties of elements in geological model were evaluated.

Geological-structural interpretation using products of remote sensing in the region of Carrancas, Minas Gerais, Brazil

Science.gov (United States)

Parada, N. D. J. (Principal Investigator); Dossantos, A. R.; Dosanjos, C. E.; Barbosa, M. P.; Veneziani, P.

1982-01-01

The efficiency of some criteria developed for the utilization of small scale and low resolution remote sensing products to map geological and structural features was demonstrated. Those criteria were adapted from the Logical Method of Photointerpretation which consists of textural qualitative analysis of landforms and drainage net patterns. LANDSAT images of channel 5 and 7, 4 LANDSAT-RBV scenes, and 1 radar mosiac were utilized. The region of study is characterized by supracrustal metassediments (quartzites and micaschist) folded according to a "zig-zag" pattern and gnaissic basement. Lithological-structural definition was considered outstanding when compared to data acquired during field work, bibliographic data and geologic maps acquired in larger scales.

Characterization of shale gas enrichment in the Wufeng Formation–Longmaxi Formation in the Sichuan Basin of China and evaluation of its geological construction–transformation evolution sequence

Directory of Open Access Journals (Sweden)

Zhiliang He

2017-02-01

Full Text Available Shale gas in Upper Ordovician Wufeng Formation–Lower Silurian Longmaxi Formation in the Sichuan Basin is one of the key strata being explored and developed in China, where shale gas reservoirs have been found in Fuling, Weiyuan, Changning and Zhaotong. Characteristics of shale gas enrichment in the formation shown by detailed profiling and analysis are summarized as “high, handsome and rich”. “High” mainly refers to the high quality of original materials for the formation of shale with excellent key parameters, including the good type and high abundance of organic matters, high content of brittle minerals and moderate thermal evolution. “Handsome” means late and weak deformation, favorable deformation mode and structure, and appropriate uplift and current burial depth. “Rich” includes high gas content, high formation pressure coefficient, good reservoir property, favorable reservoir scale transformation and high initial and final output, with relative ease of development and obvious economic benefit. For shale gas enrichment and high yield, it is important that the combination of shale was deposited and formed in excellent conditions (geological construction, and then underwent appropriate tectonic deformation, uplift, and erosion (geological transformation. Evaluation based on geological construction (evolution sequence from formation to the reservoir includes sequence stratigraphy and sediment, hydrocarbon generation and formation of reservoir pores. Based on geological transformation (evolution sequence from the reservoir to preservation, the strata should be evaluated for structural deformation, the formation of reservoir fracture and preservation of shale gas. The evaluation of the “construction - transformation” sequence is to cover the whole process of shale gas formation and preservation. This way, both positive and negative effects of the formation-transformation sequence on shale gas are assessed. The evaluation

Sedimentary facies control on mechanical and fracture stratigraphy in turbidites

NARCIS (Netherlands)

Ogata, Kei; Storti, Fabrizio; Balsamo, Fabrizio; Tinterri, Roberto; Bedogni, Enrico; Fetter, Marcos; Gomes, Leonardo; Hatushika, Raphael

2017-01-01

Natural fracture networks exert a first-order control on the exploitation of resources such as aquifers, hydrocarbons, and geothermal reservoirs, and on environmental issues like underground gas storage and waste disposal. Fractures and the mechanical stratigraphy of layered sequences have been

Geology and geohydrology of the Palo Duro Basin, Texas Panhandle. A report on the progress of nuclear isolation feasibility studies, 1980. Annual report, October 1, 1979-September 30, 1980

International Nuclear Information System (INIS)

Gustavson, T.C.; Bassett, R.L.; Finley, R.J.

1981-01-01

Since early 1977, the Bureau of Economic Geology has been evaluating several salt-bearing basins within the State of Texas as part of the national nuclear repository program. The Bureau, a research unit of the University of Texas and the State of Texas, is conducting a long-term program to gather and interpret all geologic and hydrologic information necessary for description, delineation, and evaluation of salt-bearing and related strata in the Palo Duro and Dalhart Basins of the Texas Panhandle. The program in FY 1980 was divided into five broad research tasks, which were addressed by a surficial analysis and shallow stratigraphy group, a hydrology and geochemistry group, a basin analysis group, a host-rock analysis group, and a seismicity and tectonic environment group. The surficial analysis and shallow stratigraphy group has collected remotely sensed, surface and subsurface data to describe land resources, surface processes, and rates and styles of geomorphic development. The hydrology and geochemistry group has continued analysis of shallow and deep fluid circulation within the basins and has initiated studies of rock and fluid geochemistry within the salt-bearing units. The basin analysis group has characterized the major salt-bearing stratigraphic units within the basins and has assessed the potential for generating and trapping hydrocarbons within the basins. Concurrently, the host-rock analysis group has continued a study of cores from two drilling sites for analysis of salt and other lithologic units within the cores. The newly formed seismicity and tectonic environment group has initiated studies of deep-basement structure and tetonic development of the basin and has made an analysis of surface fracture systems. This paper, a summary of progress during FY 1980, presents principal conclusions and reviews methods used and types of data and maps generated

Database for the Geologic Map of the Skykomish River 30-Minute by 60-Minute Quadrangle, Washington (I-1963)

Science.gov (United States)

Tabor, R.W.; Frizzell, V.A.; Booth, D.B.; Waitt, R.B.; Whetten, J.T.; Zartman, R.E.

2006-01-01

This digital map database has been prepared from the published geologic map of the Skykomish River 30- by 60-minute quadrangle by the senior author. Together with the accompanying text files as PDF, it provides information on the geologic structure and stratigraphy of the area covered. The database delineates map units that are identified by general age and lithology following the stratigraphic nomenclature of the U.S. Geological Survey. The authors mapped most of the bedrock geology at 1:100,000 scale, but compiled Quaternary units at 1:24,000 scale. The Quaternary contacts and structural data have been much simplified for the 1:100,000-scale map and database. The spatial resolution (scale) of the database is 1:100,000 or smaller. From the eastern-most edges of suburban Seattle, the Skykomish River quadrangle stretches east across the low rolling hills and broad river valleys of the Puget Lowland, across the forested foothills of the North Cascades, and across high meadowlands to the bare rock peaks of the Cascade crest. The Straight Creek Fault, a major Pacific Northwest structure which almost bisects the quadrangle, mostly separates unmetamorphosed and low-grade metamorphic Paleozoic and Mesozoic oceanic rocks on the west from medium- to high-grade metamorphic rocks on the east. Within the quadrangle the lower grade rocks are mostly Mesozoic melange units. To the east, the higher-grade terrane is mostly the Chiwaukum Schist and related gneisses of the Nason terrane and invading mid-Cretaceous stitching plutons. The Early Cretaceous Easton Metamorphic Suite crops out on both sides of the Straight Creek fault and records it's dextral displacement. On the south margin of the quadrangle, the fault separates the lower Eocene Swauk Formation on the east from the upper Eocene and Oligocene(?) Naches Formation and, farther north, its correlative Barlow Pass Volcanics the west. Stratigraphically equivalent rocks of the Puget Group crop out farther to the west. Rocks of

Regional evolution of geological structure in south China and U mineralization

International Nuclear Information System (INIS)

Chen Guoda; Kang Zili; Shen Jinrui; Jin Yushu

1992-01-01

This paper states the development laws of regional geological structure of South China and its controlling effect on uranium deposit evolution, and the characteristics of rich uranium formation in different periods of geo-history are analysed. It also discusses the relationship between the distribution of time and space and tectonic structure and environmental vicissitudes. The rock-magma activities-the strong formation of the Diwa Era is of great significance to the formation of uranium deposits within the region, especially to the formation of a series of multi-genesis polygene uranium deposits which are a potential direction in which to look for minerals within the region

Lithostratigraphy, petrography, biostratigraphy, and strontium-isotope stratigraphy of the surficial aquifer system of western Collier County, Florida

Science.gov (United States)

Edwards, L.E.; Weedman, S.D.; Simmons, R.; Scott, T.M.; Brewster-Wingard, G. L.; Ishman, S.E.; Carlin, N.M.

1998-01-01

In 1996, seven cores were recovered in western Collier County, southwestern Florida, to acquire subsurface geologic and hydrologic data to support ground-water modeling efforts. This report presents the lithostratigraphy, X-ray diffraction analyses, petrography, biostratigraphy, and strontium-isotope stratigraphy of these cores. The oldest unit encountered in the study cores is an unnamed formation that is late Miocene. At least four depositional sequences are present within this formation. Calculated age of the formation, based on strontium-isotope stratigraphy, ranges from 9.5 to 5.7 Ma (million years ago). An unconformity within this formation that represents a hiatus of at least 2 million years is indicated in the Old Pump Road core. In two cores, Collier-Seminole and Old Pump Road, the uppermost sediments of the unnamed formation are not dated by strontium isotopes, and, based on the fossils present, these sediments could be as young as Pliocene. In another core (Fakahatchee Strand-Ranger Station), the upper part of the unnamed formation is dated by mollusks as Pliocene. The Tamiami Formation overlies the unnamed formation throughout the study area and is represented by the Ochopee Limestone Member. The unit is Pliocene and probably includes the interval of time near the early/late Pliocene boundary. Strontium-isotope analysis indicates an early Pliocene age (calculated ages range from 5.1 to 3.5 Ma), but the margin of error includes the latest Miocene and the late Pliocene. The dinocyst assemblages in the Ochopee typically are not age-diagnostic, but, near the base of the unit in the Collier-Seminole, Jones Grade, and Fakahatchee Strand State Forest cores, they indicate an age of late Miocene or Pliocene. The molluscan assemblages indicate a Pliocene age for the Ochopee, and a distinctive assemblage of Carditimera arata and Chione cortinaria in several of the cores specifically indicates an age near the early/late Pliocene boundary. Undifferentiated sands

Quaternary Geological Phenomena in Labuhan Area, Pandeglang Regency, Banten Province

Directory of Open Access Journals (Sweden)

U. Lumban Batu

2014-07-01

Full Text Available DOI: 10.17014/ijog.v7i4.148Geological features in Labuhan area were studied from the middle of October to the middle of November 2011 covering seventy days. Surface and subsurface data were obtained from interpretation of landsat images and shallow hand-auger boreholes. The geological features are distinctly associated with active tectonics. The stratigraphy clearly indicates at least three phases of tectonic activities since the Late Miocene until Holocene. Tectonics of phase one occurred in the Late Miocene; phase two took place in the period from Pliocene to Late Pleistocene, while tectonics phase three is ongoing in the Holocene. Volcanic activity has intensified since the Early Pleistocene. The landsat images show an irregular outline of the northern coast line. This penomenon is interpreted to be the result of tectonic uplift. On the other hand, the southern coast is linear in plan which is interpreted to correlate with tectonic subsidence. Furthermore, stratigraphic correlation shows that depositional environment changed vertically due to a local subsidence. The northern researched area is occupied by Pleistocene volcanic eruption centres, whilst the younger ones tend to shift southward. This fact tends to indicate that the subduction zone moved southward slowly.

Solar illumination geometry and its influence on the observance of geological structures in orbital imagery

Science.gov (United States)

Rodrigues, Jose Eduardo; Liu, Chan Chiang

1991-04-01

The geology of the westernmost part of Rio de Janeiro State (Brazil) is characterized by the conspicuous presence of the Alem Paraiba lineament, a large shear zone extending more than 200 km in N50-60E direction. Parts of Paraiba do Sul river and of the regional topography are strongly related to this geologic feature. Several other lineament directions complete the structural framework that can be seen on remote sensing products. According to well accepted theories of photointerpretation, LANDSAT images with low sun elevation angles should more clearly show those lineaments, because the shadow enhancement of the relief is greatest. Also, considering the high grade of relief conditionment by the Alem Paraiba lineament, it is expected that this structure could be clearly observed on LANDSAT images of all seasons. However, these hypotheses are not confirmed. The images with low sun elevation angles belong to the epoch (winter) in which the solar azimuths are nearly parallel to the regional structure, making its identification difficult. In summer, the images have high sun elevation angles but their solar azimuths, oblique to the regional structures, allow an adequate identification of the main structural trend.

Conduct of Geologic Field Work During Planetary Exploration: Why Geology Matters

Science.gov (United States)

Eppler, Dean B.

2010-01-01

The science of field geology is the investigative process of determining the distribution of rock units and structures on a planet fs surface, and it is the first-order data set that informs all subsequent studies of a planet, such as geochemistry, geochronology, geophysics, or remote sensing. For future missions to the Moon and Mars, the surface systems deployed must support the conduct of field geology if these endeavors are to be scientifically useful. This lecture discussed what field geology is all about.why it is important, how it is done, how conducting field geology informs many other sciences, and how it affects the design of surface systems and the implementation of operations in the future.

Application of PALSAR-2 remote sensing data for structural geology and topographic mapping in Kelantan river basin, Malaysia

Science.gov (United States)

Beiranvand Pour, Amin; Hashim, Mazlan

2016-06-01

Natural hazards of geological origin are one of major problem during heavy monsoons rainfall in Kelantan state, peninsular Malaysia. Several landslides occur in this region are obviously connected to geological and topographical features, every year. Satellite synthetic aperture radar (SAR) data are particularly applicable for detection of geological structural and topographical features in tropical conditions. In this study, Phased Array type L-band Synthetic Aperture Radar (PALSAR-2), remote sensing data were used to identify high potential risk and susceptible zones for landslide in the Kelantan river basin. Adaptive Local Sigma filter was selected and applied to accomplish speckle reduction and preserving both edges and features in PALSAR-2 fine mode observation images. Different polarization images were integrated to enhance geological structures. Additionally, directional filters were applied to the PALSAR-2 Local Sigma resultant image for edge enhancement and detailed identification of linear features. Several faults, drainage patterns and lithological contact layers were identified at regional scale. In order to assess the results, fieldwork and GPS survey were conducted in the landslide affected zones in the Kelantan river basin. Results demonstrate the most of the landslides were associated with N-S, NNW-SSE and NE-SW trending faults, angulate drainage pattern and metamorphic and Quaternary units. Consequently, geologic structural map were produced for Kelantan river basin using recent PALSAR-2 data, which could be broadly applicable for landslide hazard assessment and delineation of high potential risk and susceptible areas. Landslide mitigation programmes could be conducted in the landslide recurrence regions for reducing catastrophes leading to economic losses and death.

Non-metric close range photogrammetric system for mapping geologic structures in mines

Energy Technology Data Exchange (ETDEWEB)

Brandow, V D

1976-01-01

A stereographic close-range photogrammetric method of obtaining structural data for mine roof stability analyses is described. Stereo pairs were taken with 70 mm and 35 mm non-metric cameras. Photo co-ordinates were measured with a stereo-comparator and reduced by the direct linear transformation method. Field trials demonstrate that the technique is sufficiently accurate for geological work and is a practical method of mapping.

Geologic map of the Rifle Falls quadrangle, Garfield County, Colorado

Science.gov (United States)

Scott, Robert B.; Shroba, Ralph R.; Egger, Anne

2001-01-01

New 1:24,000-scale geologic map of the Rifle Falls 7.5' quadrangle, in support of the USGS Western Colorado I-70 Corridor Cooperative Geologic Mapping Project, provides new interpretations of the stratigraphy, structure, and geologic hazards in the area of the southwest flank of the White River uplift. Bedrock strata include the Upper Cretaceous Iles Formation through Ordovician and Cambrian units. The Iles Formation includes the Cozzette Sandstone and Corcoran Sandstone Members, which are undivided. The Mancos Shale is divided into three members, an upper member, the Niobrara Member, and a lower member. The Lower Cretaceous Dakota Sandstone, the Upper Jurassic Morrison Formation, and the Entrada Sandstone are present. Below the Upper Jurassic Entrada Sandstone, the easternmost limit of the Lower Jurassic and Upper Triassic Glen Canyon Sandstone is recognized. Both the Upper Triassic Chinle Formation and the Lower Triassic(?) and Permian State Bridge Formation are present. The Pennsylvanian and Permian Maroon Formation is divided into two members, the Schoolhouse Member and a lower member. All the exposures of the Middle Pennsylvanian Eagle Evaporite intruded into the Middle Pennsylvanian Eagle Valley Formation, which includes locally mappable limestone beds. The Middle and Lower Pennsylvanian Belden Formation and the Lower Mississippian Leadville Limestone are present. The Upper Devonian Chaffee Group is divided into the Dyer Dolomite, which is broken into the Coffee Pot Member and the Broken Rib Member, and the Parting Formation. Ordovician through Cambrian units are undivided. The southwest flank of the White River uplift is a late Laramide structure that is represented by the steeply southwest-dipping Grand Hogback, which is only present in the southwestern corner of the map area, and less steeply southwest-dipping older strata that flatten to nearly horizontal attitudes in the northern part of the map area. Between these two is a large-offset, mid

Use of space imagery for studying geologic structure of the North-Ustyurtskaya oil and gas-bearing region

Energy Technology Data Exchange (ETDEWEB)

Lion, Yu A; Solovyova, L I

1981-01-01

Overview of issues concerning landscape and geomorphologic analysis of space imagery and the subsequent interpretation of structural and geologic values with use of geophysical data. Examples of clues of different value structural elements on images of differing generalization levels. Potential for studying overall patterns for local structures on the basis of structural and geomorphologic zonation is discussed.

Granites petrology, structure, geological setting, and metallogeny

CERN Document Server

Nédélec, Anne; Bowden, Peter

2015-01-01

Granites are emblematic rocks developed from a magma that crystallized in the Earth’s crust. They ultimately outcrop at the surface worldwide. This book, translated and updated from the original French edition Pétrologie des Granites (2011) is a modern presentation of granitic rocks from magma genesis to their crystallization at a higher level into the crust. Segregation from the source, magma ascent and shapes of granitic intrusions are also discussed, as well as the eventual formation of hybrid rocks by mingling/mixing processes and the thermomechanical aspects in country rocks around granite plutons. Modern techniques for structural studies of granites are detailed extensively. Granites are considered in their geological spatial and temporal frame, in relation with plate tectonics and Earth history from the Archaean eon. A chapter on granite metallogeny explains how elements of economic interest are concentrated during magma crystallization, and examples of Sn, Cu, F and U ore deposits are presented. Mi...

The geological and structural characterization of the Olkiluoto site in a critical perspective

International Nuclear Information System (INIS)

Cosgrove, J.; Jokinen, J.; Siivola, J.; Tiren, S.

2003-05-01

This report comments on aspects of Posiva's work relating to the interests of the IMGS (Investigations and Modelling of Geological Structures) Group who is concerned with the potential impact of the tectonic and geological setting of the Olkiluoto site, on the construction a deep repository for spent nuclear fuel. Since the Group's last report (IMGS 2002) a variety of relevant publications have been produced by Posiva. A number of issues have been identified in these documents relating to the procedure for updating the Bedrock model, factors influencing the location and layout of ONKALO, the mapping procedure planned for the access tunnel, the problem of oversimplification and uncertainties and the proposed extension of the repository. These are discussed in the present report. (orig.)

Proceedings of the Geophysical Laboratory/Lawrence Radiation Laboratory Cratering Symposium

Energy Technology Data Exchange (ETDEWEB)

Nordyke, Milo D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

1961-10-01

The geological papers in this morning's session will deal descriptively with surficial features and end products of impact craters caused by meteorite falls. Such items as breccia, structural deformation, normal and inverse stratigraphy, glass (fused rock), and coesite will frequently be mentioned. Meteor and explosion crater data are presented.

Application potential of sequence stratigraphy to prospecting for sandstone-type uranium deposit in continental depositional basins

International Nuclear Information System (INIS)

Li Shengxiang; Chen Zhaobo; Chen Zuyi; Xiang Weidong; Cai Yuqi

2001-01-01

Sequence stratigraphy has been widely used in hydrocarbon exploration and development, and great achievements have been achieved. However, its application to the prospecting for sandstone-type uranium deposits is just beginning. The metallogenic characteristics of sandstone-type uranium deposits and those of oil and gas are compared, and the relationship between sandstone-type uranium metallogenesis and the system tracts of sequence stratigraphy is studied. The authors propose that highest and system tracts are the main targets for prospecting interlayer oxidation zone type sandstone uranium deposits, and the incised valleys of low stand system tracts are favourable places for phreatic oxidation zone type sandstone uranium deposits, and transgressive system tracts are generally unfavorable to the formation of in-situ leachable sandstone-type uranium deposits. Finally, the authors look ahead the application potential of sequence stratigraphy to the prospecting for sandstone-type uranium deposits in continental depositional basins

The Strabo digital data system for Structural Geology and Tectonics

Science.gov (United States)

Tikoff, Basil; Newman, Julie; Walker, J. Doug; Williams, Randy; Michels, Zach; Andrews, Joseph; Bunse, Emily; Ash, Jason; Good, Jessica

2017-04-01

We are developing the Strabo data system for the structural geology and tectonics community. The data system will allow researchers to share primary data, apply new types of analytical procedures (e.g., statistical analysis), facilitate interaction with other geology communities, and allow new types of science to be done. The data system is based on a graph database, rather than relational database approach, to increase flexibility and allow geologically realistic relationships between observations and measurements. Development is occurring on: 1) A field-based application that runs on iOS and Android mobile devices and can function in either internet connected or disconnected environments; and 2) A desktop system that runs only in connected settings and directly addresses the back-end database. The field application also makes extensive use of images, such as photos or sketches, which can be hierarchically arranged with encapsulated field measurements/observations across all scales. The system also accepts Shapefile, GEOJSON, KML formats made in ArcGIS and QGIS, and will allow export to these formats as well. Strabo uses two main concepts to organize the data: Spots and Tags. A Spot is any observation that characterizes a specific area. Below GPS resolution, a Spot can be tied to an image (outcrop photo, thin section, etc.). Spots are related in a purely spatial manner (one spot encloses anther spot, which encloses another, etc.). Tags provide a linkage between conceptually related spots. Together, this organization works seamlessly with the workflow of most geologists. We are expanding this effort to include microstructural data, as well as to the disciplines of sedimentology and petrology.

Technical support for GEIS: radioactive waste isolation in geologic formations. Volume 3. Stratigraphies of salt, granite, shale, and basalt

International Nuclear Information System (INIS)

1978-04-01

This study presents the methodology and basic literature used to develop generic stratigraphic sections for the various geologic repository host rocks under considerations: salt, granite, shale and basalt

Orthogonal Matching Pursuit for Enhanced Recovery of Sparse Geological Structures With the Ensemble Kalman Filter

KAUST Repository

Sana, Furrukh; Katterbauer, Klemens; Al-Naffouri, Tareq Y.; Hoteit, Ibrahim

2016-01-01

Estimating the locations and the structures of subsurface channels holds significant importance for forecasting the subsurface flow and reservoir productivity. These channels exhibit high permeability and are easily contrasted from the low-permeability rock formations in their surroundings. This enables formulating the flow channels estimation problem as a sparse field recovery problem. The ensemble Kalman filter (EnKF) is a widely used technique for the estimation and calibration of subsurface reservoir model parameters, such as permeability. However, the conventional EnKF framework does not provide an efficient mechanism to incorporate prior information on the wide varieties of subsurface geological structures, and often fails to recover and preserve flow channel structures. Recent works in the area of compressed sensing (CS) have shown that estimating in a sparse domain, using algorithms such as the orthogonal matching pursuit (OMP), may significantly improve the estimation quality when dealing with such problems. We propose two new, and computationally efficient, algorithms combining OMP with the EnKF to improve the estimation and recovery of the subsurface geological channels. Numerical experiments suggest that the proposed algorithms provide efficient mechanisms to incorporate and preserve structural information in the EnKF and result in significant improvements in recovering flow channel structures.

Orthogonal Matching Pursuit for Enhanced Recovery of Sparse Geological Structures With the Ensemble Kalman Filter

KAUST Repository

Sana, Furrukh

2016-02-23

Estimating the locations and the structures of subsurface channels holds significant importance for forecasting the subsurface flow and reservoir productivity. These channels exhibit high permeability and are easily contrasted from the low-permeability rock formations in their surroundings. This enables formulating the flow channels estimation problem as a sparse field recovery problem. The ensemble Kalman filter (EnKF) is a widely used technique for the estimation and calibration of subsurface reservoir model parameters, such as permeability. However, the conventional EnKF framework does not provide an efficient mechanism to incorporate prior information on the wide varieties of subsurface geological structures, and often fails to recover and preserve flow channel structures. Recent works in the area of compressed sensing (CS) have shown that estimating in a sparse domain, using algorithms such as the orthogonal matching pursuit (OMP), may significantly improve the estimation quality when dealing with such problems. We propose two new, and computationally efficient, algorithms combining OMP with the EnKF to improve the estimation and recovery of the subsurface geological channels. Numerical experiments suggest that the proposed algorithms provide efficient mechanisms to incorporate and preserve structural information in the EnKF and result in significant improvements in recovering flow channel structures.

Conclusions of the Ad-hoc Review Committee (ARC) on the International Commission on Stratigraphy (ICS) of the International Union of Geological Sciences (IUGS) (Paris, 7-8 November 2005)

Institute of Scientific and Technical Information of China (English)

无

2007-01-01

@@ Background Following the recommendations of the IUGS Strategic Planning Committee (2000) and IUGS Strategic Action Plan (2001)to appoint Ad-hoc Review Committees (ARCs) to hold reviewsof all IUGS-funded scientific activities on a regular basis, theIUGS Executive Committee decided at its last meeting in Vilnius, Lithuania (March 2005) that an ARC should be convened toreview the IUGS International Commission on. Stratigraphy(ICS). ICS has been part of IUGS since 1965, and the last reviewof ICS by the IUGS was in 1995.

Study on the development of geological environmental model

International Nuclear Information System (INIS)

Tsujimoto, Keiichi; Shinohara, Yoshinori; Ueta, Shinzo; Saito, Shigeyuki; Kawamura, Yuji; Tomiyama, Shingo; Ohashi, Toyo

2002-03-01

The safety performance assessment was carried out in potential geological environment in the conventional research and development of geological disposal, but the importance of safety assessment based on the repository design and scenario considering the concrete geological environment will increase in the future. The research considering the link of the major three fields of geological disposal, investigation of geological environment, repository design, and safety performance assessment, is the contemporary worldwide research theme. Hence it is important to organize information flow that contains the series of information process form the data production to analysis in the three fields, and to systemize the knowledge base that unifies the information flow hierarchically. The purpose of the research is to support the development of the unified analysis system for geological disposal. The development technology for geological environmental model studied for the second progress report by JNC are organized and examined for the purpose of developing database system with considering the suitability for the deep underground research facility. The geological environmental investigation technology and building methodology for geological structure and hydro geological structure models are organized and systemized. Furthermore, the quality assurance methods in building geological environment models are examined. Information which is used and stored in the unified analysis system are examined to design database structure of the system based on the organized methodology for building geological environmental model. The graphic processing function for data stored in the unified database are examined. furthermore, future research subjects for the development of detail models for geological disposal are surveyed to organize safety performance system. (author)

THE TECTONICS STRESS AND STRAIN FIELD MODELING ADJUSTED FOR EVOLUTION OF GEOLOGICAL STRUCTURES (SAILAG INTRUSION, EASTERN SAYAN

Directory of Open Access Journals (Sweden)

V. N. Voytenko

2013-01-01

Full Text Available The article describes a tectonophysical model showing evolution of structures in the Sailag granodiorite massif in relation to its gold-bearing capacity. The model takes into account the load patterns according to geological data, accumulated deformation, and gravity stresses. This model provides for updating the structural-geological model showing development of the intrusion body and the ore field. Forecasted are destruction patterns in the apical and above-dome parts of the massif  in the intrusion and contraction phase, formation of the long-term shear zone at the steeply dipping slope of the intrusion body, and subvertical fractures associated with the long-term shear zone and vertical mechanical ‘layering’ of the intrusive body.  

Evaluation of geological structure and uranium mineralization model in West Lemajung Sector, Kalan Basin, West Kalimantan

International Nuclear Information System (INIS)

Ngadenin; Sularto, P.

2000-01-01

The fieldwork is based on the data of strike (S0) and schistosity (S1) of cores that could not penetrate the geological structure model and result of observation on some cores has shown that U mineralization veins are not always parallel to S1. The problems were encountered in core drill data to improve the estimation of U resources from indication category to measured category. The purpose of the evaluation is to establish the advisability of geological structure model and U mineralization model which was applied by this time. The research used remapping of geological structure with surface method in the scale of 1:1000. The result of remapping shows the difference of the dipping between new geological structure model and the old model. The dipping of the new model is to South East until vertical and the old model is to North West until vertical and to South East until vertical. Despite the difference between both of them, the substantive of folding system is identical so that the new and old models can be applied in drilling in West Lemajung sector. U mineralization model of remapping result consists of 3 types : type 1 U mineralization lens form with West-East direction and vertical dipping which is associated with tourmaline, type 2 U mineralization filling in the open fractures with West-East direction and 70 o to North dipping and parallel with S1, and type 3 U mineralization fill in opening fractures with N 110 o - 130 o E the direction and 60 o to North East until subvertical dipping while the old model is only one type. It is U mineralization filling in the open fractures with West-East the direction and 70 o to North the dipping and parallel with S1. Because of this significant difference, data collection of drill core must follow the new mineralization model. (author)

Teaching and Learning Structural Geology Using SketchUp

Science.gov (United States)

Rey, Patrice

2017-04-01

The books and maps we read, the posters we pin on our walls, the TV sets and computer monitors we spend hours watching, the white (or black) boards we use to teach, all reduce our world into planar images. As a result, and through years of oblivious practice, our brain is conditioned to understand the world in two dimensions (2D) only. As structural geologists, we know that the most challenging aspect of teaching and learning structural geology is that we need to be able to mentally manipulate 2D and three-dimensional (3D) objects. Although anyone can learn through practice the art of spatial visualisation, the fact remains that the initial stages of learning structural geology are for many students very challenging, as we naively use 2D images to teach 3D concepts. While interactive 3D holography is not far away, some inexpensive tools already exist allowing us to generate interactive computer images, the free rotation, scaling and manipulation of which can help students to quickly grasp the geometry and internal architecture of 3D objects. Recently, I have experimented with SketchUp (works on Mac and Windows). SketchUp was initially released in 2000 by @Last Software, as a 3D modelling tool for architects, designers and filmmakers. It was acquired by Google in 2006 to further the development of GoogleEarth. Google released SketchUp for free, and provided a portal named 3D Warehouse for users to share their models. Google sold SketchUp to Trimble Navigation in 2012, which added Extension Warehouse for users to distribute add-ons. SketchUp models can be exported in a number of formats including .dae (digital asset exchange) useful to embed interactive 3D models into iBooks and html5 documents, and .kmz (keyhole markup language zipped) to embed interactive 3D models and cross-sections into GoogleEarth. SketchUp models can be exported into 3D pdf through the add-on SimLab, and .stl for 3D printing through the add-on SketchUp STL. A free licence is available for

Rootless tephra stratigraphy and emplacement processes

Science.gov (United States)

Hamilton, Christopher W.; Fitch, Erin P.; Fagents, Sarah A.; Thordarson, Thorvaldur

2017-01-01

Volcanic rootless cones are the products of thermohydraulic explosions involving rapid heat transfer from active lava (fuel) to external sources of water (coolant). Rootless eruptions are attributed to molten fuel-coolant interactions (MFCIs), but previous studies have not performed systematic investigations of rootless tephrostratigraphy and grain-size distributions to establish a baseline for evaluating relationships between environmental factors, MFCI efficiency, fragmentation, and patterns of tephra dispersal. This study examines a 13.55-m-thick vertical section through an archetypal rootless tephra sequence, which includes a rhythmic succession of 28 bed pairs. Each bed pair is interpreted to be the result of a discrete explosion cycle, with fine-grained basal material emplaced dominantly as tephra fall during an energetic opening phase, followed by the deposition of coarser-grained material mainly as ballistic ejecta during a weaker coda phase. Nine additional layers are interleaved throughout the stratigraphy and are interpreted to be dilute pyroclastic density current (PDC) deposits. Overall, the stratigraphy divides into four units: unit 1 contains the largest number of sediment-rich PDC deposits, units 2 and 3 are dominated by a rhythmic succession of bed pairs, and unit 4 includes welded layers. This pattern is consistent with a general decrease in MFCI efficiency due to the depletion of locally available coolant (i.e., groundwater or wet sediments). Changing conduit/vent geometries, mixing conditions, coolant and melt temperatures, and/or coolant impurities may also have affected MFCI efficiency, but the rhythmic nature of the bed pairs implies a periodic explosion process, which can be explained by temporary increases in the water-to-lava mass ratio during cycles of groundwater recharge.

Geologic map of the Frisco quadrangle, Summit County, Colorado

Science.gov (United States)

Kellogg, Karl S.; Bartos, Paul J.; Williams, Cindy L.

2002-01-01

New 1:24,000-scale geologic mapping along the Interstate-70 urban corridor in western Colorado, in support of the USGS Central Region State/USGS Cooperative Geologic Mapping Project, is contributing to a more complete understanding of the stratigraphy, structure, tectonic evolution, and hazard potential of this rapidly developing region. The 1:24,000-scale Frisco quadrangle is near the headwaters of the Blue River and straddles features of the Blue River graben (Kellogg, K.S., 1999, Neogene basins of the northern Rio Grande rift?partitioning and asymmetry inherited from Laramide and older uplifts: Tectonophysics, v. 305, p. 141-152.), part of the northernmost reaches of the Rio Grande rift, a major late Oligocene to recent zone of extension that extends from Colorado to Mexico. The Williams Range thrust fault, the western structural margin of the Colorado Front Range, cuts the northeastern corner of the quadrangle. The oldest rocks in the quadrangle underlie the Tenmile Range and include biotite-sillimanite schist and gneiss, amphibolite, and migmatite that are intruded by granite inferred to be part of the 1,667-1,750 Ma Routt Plutonic Suite (Tweto, Ogden, 1987, Rock units of the Precambrian- basement in Colorado: U.S. Geological Survey Professional Paper 1321-A, 54 p.). The oldest sedimentary unit is the Pennsylvanian Maroon Formation, a sequence of red sandstone, conglomerate, and interbedded shale. The thickest sequence of sedimentary rocks is Cretaceous in age and includes at least 500 m of the Upper Cretaceous Pierre Shale. The sedimentary rocks are intruded by sills and dikes of dacite porphyry sills of Swan Mountain, dated at 44 Ma (Marvin, R.F., Mehnert, H.H., Naeser, C.W., and Zartman, R.E., 1989, U.S. Geological Survey radiometric ages, compilation ?C??Part five?Colorado, Montana, Utah, and Wyoming: Isochron/West, no. 53, p. 14-19. Simmons, E.C., and Hedge, C.E., 1978, Minor-element and Sr-isotope geochemistry of Tertiary stocks, Colorado mineral belt

Method of magnetic susceptibility mapping of drilled cores. Experimental measurements for geologic structures determination

International Nuclear Information System (INIS)

Delrive, C.

1993-01-01

The evaluation of the safety of a deep geologic repository for dangerous materials requires the knowledge of the interstitial system of the surrounding host rock. A method is proposed for the determination of geologic structures (in particular fractures) from the magnetic susceptibility mapping of drilled cores. The feasibility of the method has been demonstrated using a SQUID magneto-gradient meter. A measurement tool using a new magnetic susceptibility captor and a testing bench have been developed. This tool allows the measurement of rocks with a magnetic susceptibility greater than 10 -5 SI units and can generate magnetic susceptibility maps with 4 x 4 mm 2 pixels. A magnetic visibility criterion has been defined which allows to foresee if a structure is visible or not. According to the measurements done, it is shown that any centimeter-scale structure with a sufficient magnetic contrast (20%) with respect to the matrix is visible. Therefore, the dip and the orientation of such structure can be determined with a 3 degree and a 5 degree precision, respectively. The position of the structure along the core axis is known with a 4 mm precision. On the other hand, about half of the magnetic contrasts observed do not correspond to the visual analyses and can be explained by very small variations of the mineralogic composition. This last point offers some interesting ways for future research using magnetic susceptibility mapping. (J.S.). 31 refs., 90 figs., 18 tabs., 2 photos., 6 appends

Geological heritage of Morocco

International Nuclear Information System (INIS)

Elhadi, H.; Tahiri, A.

2012-01-01

Full text: The soil and subsoil of Morocco are rich in geological phenomena that bear the imprint of a history that goes back in time more than 2000 million years. Very many sites geologically remarkable exposed in accessible outcrops, with good quality remain unknown to the general public and therefore deserve to be vulgarized. It is a memory to acquaint to the present generations but also to preserve for future generations. In total, a rich geological heritage in many ways: Varied landscapes, international stratotypes, various geological structures, varied rocks, mineral associations, a huge procession of fossiles, remnants of oceanic crust (ophiolites) among oldests ones in the world (800my), etc... For this geological heritage, an approach of an overall inventory is needed, both regionally and nationally, taking into account all the skills of the earth sciences. This will put the item on the natural (geological) potentialities as a lever for sustainable regional development. For this, it is necessary to implement a strategy of ''geoconservation'' for the preservation and assessment of the geological heritage.

Stratigraphy and Tectonics of Southeastern Serenitatis. Ph.D. Thesis

Science.gov (United States)

Maxwell, T. A.

1976-01-01

Results of investigations of returned Apollo 17 samples, and Apollo 15 and 17 photographs have provided a broad data base on which to interpret the southeastern Serenitatis region of the moon. Although many of the pre-Apollo 17 mission interpretations remain valid, detailed mapping of this region and correlation with earth-based and orbital remote-sensing data have resulted in a revision of the local mare stratigraphy.

Forearc Basin Stratigraphy and Interactions With Accretionary Wedge Growth According to the Critical Taper Concept

Science.gov (United States)

Noda, Atsushi

2018-03-01

Forearc basins are important constituents of sediment traps along subduction zones; the basin stratigraphy records various events that the basin experienced. Although the linkage between basin formation and accretionary wedge growth suggests that mass balance exerts a key control on their evolution, the interaction processes between basin and basement remain poorly understood. This study performed 2-D numerical simulations in which basin stratigraphy was controlled by changes in sediment fluxes with accretionary wedge growth according to the critical taper concept. The resultant stratigraphy depended on the degree of filling (i.e., whether the basin was underfilled or overfilled) and the volume balance between the sediment flux supplied to the basin from the hinterland and the accommodation space in the basin. The trenchward progradation of deposition with onlapping contacts on the trenchside basin floor occurred during the underfilled phase, which formed a wedge-shaped sedimentary unit. In contrast, the landward migration of the depocenter, with the tilting of strata, was characteristic for the overfilled phase. Condensed sections marked stratigraphic boundaries, indicating when sediment supply or accommodation space was limited. The accommodation-limited intervals could have formed during the end of wedge uplift or when the taper angle decreased and possibly associated with the development of submarine canyons as conduits for bypassing sediments from the hinterland. Variations in sediment fluxes and their balance exerted a strong influence on the stratigraphic patterns in forearc basins. Assessing basin stratigraphy could be a key to evaluating how subduction zones evolve through their interactions with changing surface processes.

The INTIMATE event stratigraphy of the last glacial period

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Olander Rasmussen, Sune; Svensson, Anders

2015-04-01

The North Atlantic INTIMATE (INtegration of Ice-core, MArine and TErrestrial records) group has previously recommended an Event Stratigraphy approach for the synchronisation of records of the Last Termination using the Greenland ice core records as the regional stratotypes. A key element of these protocols has been the formal definition of numbered Greenland Stadials (GS) and Greenland Interstadials (GI) within the past glacial period as the Greenland expressions of the characteristic Dansgaard-Oeschger events that represent cold and warm phases of the North Atlantic region, respectively. Using a recent synchronization of the NGRIP, GRIP, and GISP2 ice cores that allows the parallel analysis of all three records on a common time scale, we here present an extension of the GS/GI stratigraphic template to the entire glacial period. In addition to the well-known sequence of Dansgaard-Oeschger events that were first defined and numbered in the ice core records more than two decades ago, a number of short-lived climatic oscillations have been identified in the three synchronized records. Some of these events have been observed in other studies, but we here propose a consistent scheme for discriminating and naming all the significant climatic events of the last glacial period that are represented in the Greenland ice cores. In addition to presenting the updated event stratigraphy, we make a series of recommendations on how to refer to these periods in a way that promotes unambiguous comparison and correlation between different proxy records, providing a more secure basis for investigating the dynamics and fundamental causes of these climatic perturbations. The work presented is a part of a newly published paper in an INTIMATE special issue of Quaternary Science Reviews: Rasmussen et al., 'A stratigraphic framework for abrupt climatic changes during the Last Glacial period based on three synchronized Greenland ice-core records: refining and extending the INTIMATE event

The Dom Feliciano belt and its relations with the craton of the Rio de la Plata and Punta del Este ground-Geology and geochronology

International Nuclear Information System (INIS)

Preciozzi, F.; Peel, E.; Sanchez, L.; Basei, M.; Ledesma, J.; Muzio, R.

2005-01-01

This research was framed in an interdisciplinary project, whose main objective was to make an approach to the geological, tectonic and geochronological evolution of Dom Feliciano Belt and adjacent land partners, especially the Río de la Plata Craton and Land Punta del Este. As was proposed in the project, special attention to geochronological studies from geological transects lent controlled. This yielded the expected level major step forward, not only with regard to the age of different units, but what makes the establishment of an adequate stratigraphy of them. Similarly, geochemical, petrographic and geochronological studies allowed essentially make geotectonic and geologic correlations with the southern portion of Brazil and the western portion of the land I africanos.lo expand involving more project goals in si.En effect began to manifest as a need to know the evolution of equivalent units both in the southern portion of Brazil and Africa Occidental.Estos fundamentalmnete work with West Africa were made with contributions from CONICYT Project 6009 under Projects Geological Correlation 438, 450 and 478 .this pertimitio exchange ideas with leading scientists worldwide many of whom ended up collaborating with it

Study on radon geological potential of Beijing city

International Nuclear Information System (INIS)

Liu Qingcheng; Wu Xinmin; Liu Yujuan; Yang Yaxin; Zhang Ye

2009-01-01

According to elemental geochemistry in Beijing, the uranium content in the area was measured, and distribution of radon concentration was predicted. Based on the uranium-radium equilibrium coefficient, porosity and diffusion coefficient, which were either measured or calculated, the radon geological potential of Beijing city was studied using γ-ray spectroscopy or mass spectroscopy and certain models were used to calculate the relation between radon geological potential and lithology and geological structure. The results showed that radon geological potential of Beijing city could be divided into four zones, tend of every zone coincides with the main structure, and the potential values nearly relate with geological factors. (authors)

Soil Structure Evaluation Across Geologic Transition Zones Using 2D Electrical Resistivity Imaging Technique

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Geraldine C Anukwu

2017-06-01

Full Text Available This study utilizes the electrical resistivity values obtained using 2-D Electrical resistivity imaging (ERI technique to evaluate the subsurface lithology across different geological units. The primary objective was to determine the effect of subsurface lithology on the integrity of a road pavement, which had developed cracks and potholes at various locations. The dipole-dipole configuration was utilized and a total of nine traverses were established in the study area, whose geology cuts across both the basement and sedimentary complexes. The inverted resistivity section obtained showed significant variation in resistivity along established traverses and also across the different rock units, with the resistivity value ranging from about 4 ohm-m to greater than 7000 ohm- m. The lithology as interpreted from the resistivity section revealed the presence topsoil, clay, sandy clay, sand, sand stones/basement rocks, with varying vertical and horizontal arrangements to a depth of 40m. Results suggest that the geologic sequence and structure might have contributed to the observed pavement failure. The capability of the 2D ERI as an imaging tool is observed, especially across the transition zones as depicted in this study. The study further stressed the ability of this technique if properly designed and implemented, to be capable of providing a wealth of information that could complement other traditional geotechnical and geologic techniques.

Lower Devonian Brachiopods and Stratigraphy of North Palencia (Cantabrian Mountains, Spain)

NARCIS (Netherlands)

Binnekamp, J.G.

1965-01-01

A continuous sequence of Devonian sediments is exposed in the northern part of the province of Palencia (NW-Spain), on the southern slope of the Cantabrian Mountains. This study concerns the stratigraphy and paleontology of the Lower Devonian formations. At the base of the sequence a clastic

Tidal Simulations of an Incised-Valley Fluvial System with a Physics-Based Geologic Model

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Ghayour, K.; Sun, T.

2012-12-01

Physics-based geologic modeling approaches use fluid flow in conjunction with sediment transport and deposition models to devise evolutionary geologic models that focus on underlying physical processes and attempt to resolve them at pertinent spatial and temporal scales. Physics-based models are particularly useful when the evolution of a depositional system is driven by the interplay of autogenic processes and their response to allogenic controls. This interplay can potentially create complex reservoir architectures with high permeability sedimentary bodies bounded by a hierarchy of shales that can effectively impede flow in the subsurface. The complex stratigraphy of tide-influenced fluvial systems is an example of such co-existing and interacting environments of deposition. The focus of this talk is a novel formulation of boundary conditions for hydrodynamics-driven models of sedimentary systems. In tidal simulations, a time-accurate boundary treatment is essential for proper imposition of tidal forcing and fluvial inlet conditions where the flow may be reversed at times within a tidal cycle. As such, the boundary treatment at the inlet has to accommodate for a smooth transition from inflow to outflow and vice-versa without creating numerical artifacts. Our numerical experimentations showed that boundary condition treatments based on a local (frozen) one-dimensional approach along the boundary normal which does not account for the variation of flow quantities in the tangential direction often lead to unsatisfactory results corrupted by numerical artifacts. In this talk, we propose a new boundary treatment that retains all spatial and temporal terms in the model and as such is capable to account for nonlinearities and sharp variations of model variables near boundaries. The proposed approach borrows heavily from the idea set forth by J. Sesterhenn1 for compressible Navier-Stokes equations. The methodology is successfully applied to a tide-influenced incised

Airborne electromagnetic data and processing within Leach Lake Basin, Fort Irwin, California: Chapter G in Geology and geophysics applied to groundwater hydrology at Fort Irwin, California

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Bedrosian, Paul A.; Ball, Lyndsay B.; Bloss, Benjamin R.; Buesch, David C.

2014-01-01

From December 2010 to January 2011, the U.S. Geological Survey conducted airborne electromagnetic and magnetic surveys of Leach Lake Basin within the National Training Center, Fort Irwin, California. These data were collected to characterize the subsurface and provide information needed to understand and manage groundwater resources within Fort Irwin. A resistivity stratigraphy was developed using ground-based time-domain electromagnetic soundings together with laboratory resistivity measurements on hand samples and borehole geophysical logs from nearby basins. This report releases data associated with the airborne surveys, as well as resistivity cross-sections and depth slices derived from inversion of the airborne electromagnetic data. The resulting resistivity models confirm and add to the geologic framework, constrain the hydrostratigraphy and the depth to basement, and reveal the distribution of faults and folds within the basin.

Stratigraphy and Age of Paleoproterozoic Birimian Volcaniclastic Sequence in the Cape Three Points area, Axim-Konongo (Ashanti) Belt, Southwest Ghana

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Yoshimaru, S.; Kiyokawa, S.; Ito, T.; Ikehara, M.; Horie, K.; Takehara, M.; Sano, T.; Nyame, F. K.; Tetteh, G. M.

2016-12-01

This study investigated the depositional environments and bioactivities of well preserved volcaniclastic sequences in the Cape Three Points area in the Paleoproterozoic Axim-Konongo (Ashanti) belt in the Birimian of Ghana. Our current research outlines the stratigraphy, structure, approximate age and depositional setting of the volcaniclastic sequence in the Cape Three Points area in Ghana, West Africa.Axim-Konongo (Ashanti) belt is composed of mainly andesitic basalts, volcaniclastic rocks and belt type granitoids, which are unconformably overlain by Tarkwaian conglomerates and metasedimentary rocks. The rocks show NE-SW strike with maximum depositional age of overlying metasedimentary rocks of 2154±2 Ma (U-Pb zircon; Oberthür et al., 1998). The oldest age of an intrusive into Birimian volcanic rock near Sekondi is 2174±2 Ma (U-Pb zircon; Oberthür et al., 1998). Thick volcaniclastic succession over 4000 m thickness was reconstructed for 1000 m thickness after detailed field investigations. The succession shows approximately N-S strike mainly 60-80° dip to the east and generally upward sequence. The rocks were affected by greenschist facies metamorphism. TiO2/Al2O3 ratios of chromites and whole- rock trace elements compositions with low Nb concentration and high LREE concentration support deposition on mid-deep sea floor in a volcanic arc. New age data were obtained from foliated porphyritic dyke which occurs in the Cape Three Points area. Zircon grains, measured by SHRIMP at National Institute of Polar Research (NIPR), yielded a weighted mean 204Pb-corrected 207Pb/206Pb age of 2265.6±4.6 Ma (95% confidence). Thus, the volcaniclastic sequence was deposited before 2265.6±4.6 Ma and was deformed after 2265 Ma. 2260 Ma is the oldest age at which early volcanic activity in the Birimian terrane occurred (Loh and Hirdes, 1999). References Oberthür T et al. (1998) Precambrian Research 89: 129-143 Loh G and Hirdes W (1999) Exlplanatory Notes for the Geological Map

Use of structural geology in exploration for and mining of sedimentary rock-hosted Au deposits

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Peters, Stephen G.

2001-01-01

Structural geology is an important component in regional-, district- and orebody-scale exploration and development of sedimentary rock-hosted Au deposits.Identification of timing of important structural events in an ore district allows analysis and classification of fluid conduits and construction of genetic models for ore formation.The most practical uses of structural geology deal with measurement and definition of various elements that comprise orebodies, which can then be directly applied to ore-reserve estimation,ground control,grade control, safety issues,and mine planning.District- and regional-scale structural studies are directly applicable to long-term strategic planning,economic analysis,and land ownership. Orebodies in sedimentary rock-hosted Au deposits are discrete, hypogene, epigenetic masses usually hosted in a fault zone,breccia mass, or lithologic bed or unit. These attributes allow structural geology to be directly applied to the mining and exploration of sedimentary rock-hosted Au deposits. Internal constituents in orebodies reflect unique episodes relating to ore formation.The main internal constituents in orebodies are ore minerals, gangue, and alteration minerals that usually are mixed with one another in complex patterns, the relations among which may be used to interpret the processes of orebody formation and control.Controls of orebody location and shape usually are due to structural dilatant zones caused by changes in attitude, splays, lithologic contacts,and intersections of the host conduit or unit.In addition,conceptual parameters such as district fabric,predictable distances, and stacking also are used to understand the geometry of orebodies.Controls in ore districts and location and geometry of orebodies in ore districts can be predicted to various degrees by using a number of qualitative concepts such as internal and external orebody plunges,district plunge, district stacking, conduit classification, geochemical, geobarometric and

Geologic map of the Vail West quadrangle, Eagle County, Colorado

Science.gov (United States)

Scott, Robert B.; Lidke, David J.; Grunwald, Daniel J.

2002-01-01

This new 1:24,000-scale geologic map of the Vail West 7.5' quadrangle, as part of the USGS Western Colorado I-70 Corridor Cooperative Geologic Mapping Project, provides new interpretations of the stratigraphy, structure, and geologic hazards in the area on the southwest flank of the Gore Range. Bedrock strata include Miocene tuffaceous sedimentary rocks, Mesozoic and upper Paleozoic sedimentary rocks, and undivided Early(?) Proterozoic metasedimentary and igneous rocks. Tuffaceous rocks are found in fault-tilted blocks. Only small outliers of the Dakota Sandstone, Morrison Formation, Entrada Sandstone, and Chinle Formation exist above the redbeds of the Permian-Pennsylvanian Maroon Formation and Pennsylvanian Minturn Formation, which were derived during erosion of the Ancestral Front Range east of the Gore fault zone. In the southwestern area of the map, the proximal Minturn facies change to distal Eagle Valley Formation and the Eagle Valley Evaporite basin facies. The Jacque Mountain Limestone Member, previously defined as the top of the Minturn Formation, cannot be traced to the facies change to the southwest. Abundant surficial deposits include Pinedale and Bull Lake Tills, periglacial deposits, earth-flow deposits, common diamicton deposits, common Quaternary landslide deposits, and an extensive, possibly late Pliocene landslide deposit. Landscaping has so extensively modified the land surface in the town of Vail that a modified land-surface unit was created to represent the surface unit. Laramide movement renewed activity along the Gore fault zone, producing a series of northwest-trending open anticlines and synclines in Paleozoic and Mesozoic strata, parallel to the trend of the fault zone. Tertiary down-to-the-northeast normal faults are evident and are parallel to similar faults in both the Gore Range and the Blue River valley to the northeast; presumably these are related to extensional deformation that occurred during formation of the northern end of the

Predicting snowpack stratigraphy in forested environments

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Andreadis, K. M.; Lettenmaier, D. P.

2009-04-01

The interaction of forest canopies with snow accumulation and ablation processes is critical to the hydrology of many mid- and high-latitude areas. The layered character of snowpacks increases the complexity of representing these processes and deconvolving the return signal from remote sensors. However, it offers the opportunity to infer the metamorphic signature of the snowpack and to extract additional information by combining multiple frequencies (visible and passive/active microwave). Implementation of this approach requires knowledge of the stratigraphy of snowpack microphysical properties (temperature, density, and grain size), which as a practical matter can only be produced by predictive models. A mass and energy balance model for snow accumulation and ablation processes in forested environments was developed utilizing extensive measurements of snow interception and release in a maritime mountainous site in Oregon. A multiple layer component was added to the model that also takes into account snowpack stratigraphy resulting from snow densification, vapor transport and grain growth. The model, was evaluated using two years of weighing lysimeter data and was able to reproduce the SWE evolution throughout both winters beneath the canopy as well as the nearby clearing. The model was also evaluated using measurements from a BOReal Ecosystem-Atmosphere Study (BOREAS) field site in Canada to test the robustness of the canopy snow interception algorithm in a much different climate. Simulated SWE was relatively close to the observations for the forested sites, with discrepancies evident in some cases. Although the model formulation appeared robust for both types of climates, sensitivity to parameters such as snow roughness length, maximum interception capacity and number of layers suggested the magnitude of improvements of SWE simulations that might be achieved by calibration. Finally, the model's ability to replicate large-scale snowpack layer features and their

Non-invasive NMR stratigraphy of a multi-layered artefact: an ancient detached mural painting.

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Di Tullio, Valeria; Capitani, Donatella; Presciutti, Federica; Gentile, Gennaro; Brunetti, Brunetto Giovanni; Proietti, Noemi

2013-10-01

NMR stratigraphy was used to investigate in situ, non-destructively and non-invasively, the stratigraphy of hydrogen-rich layers of an ancient Nubian detached mural painting. Because of the detachment procedure, a complex multi-layered artefact was obtained, where, besides layers of the original mural painting, also the materials used during the procedure all became constitutive parts of the artefact. NMR measurements in situ enabled monitoring of the state of conservation of the artefact and planning of minimum representative sampling to validate results obtained in situ by solid-state NMR analysis of the samples. This analysis enabled chemical characterization of all organic materials. Use of reference compounds and prepared specimens assisted data interpretation.

Assessment of planetary geologic mapping techniques for Mars using terrestrial analogs: The SP Mountain area of the San Francisco Volcanic Field, Arizona

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Tanaka, K.L.; Skinner, J.A.; Crumpler, L.S.; Dohm, J.M.

2009-01-01

We photogeologically mapped the SP Mountain region of the San Francisco Volcanic Field in northern Arizona, USA to evaluate and improve the fidelity of approaches used in geologic mapping of Mars. This test site, which was previously mapped in the field, is chiefly composed of Late Cenozoic cinder cones, lava flows, and alluvium perched on Permian limestone of the Kaibab Formation. Faulting and folding has deformed the older rocks and some of the volcanic materials, and fluvial erosion has carved drainage systems and deposited alluvium. These geologic materials and their formational and modificational histories are similar to those for regions of the Martian surface. We independently prepared four geologic maps using topographic and image data at resolutions that mimic those that are commonly used to map the geology of Mars (where consideration was included for the fact that Martian features such as lava flows are commonly much larger than their terrestrial counterparts). We primarily based our map units and stratigraphic relations on geomorphology, color contrasts, and cross-cutting relationships. Afterward, we compared our results with previously published field-based mapping results, including detailed analyses of the stratigraphy and of the spatial overlap and proximity of the field-based vs. remote-based (photogeologic) map units, contacts, and structures. Results of these analyses provide insights into how to optimize the photogeologic mapping of Mars (and, by extension, other remotely observed planetary surfaces). We recommend the following: (1) photogeologic mapping as an excellent approach to recovering the general geology of a region, along with examination of local, high-resolution datasets to gain insights into the complexity of the geology at outcrop scales; (2) delineating volcanic vents and lava-flow sequences conservatively and understanding that flow abutment and flow overlap are difficult to distinguish in remote data sets; (3) taking care to

Executive Summary -- assessment of undiscovered oil and gas resources of the San Joaquin Basin Province of California, 2003: Chapter 1 in Petroleum systems and geologic assessment of oil and gas in the San Joaquin Basin Province, California

Science.gov (United States)

Gautier, Donald L.; Scheirer, Allegra Hosford; Tennyson, Marilyn E.; Peters, Kenneth E.; Magoon, Leslie B.; Lillis, Paul G.; Charpentier, Ronald R.; Cook, Troy A.; French, Christopher D.; Klett, Timothy R.; Pollastro, Richard M.; Schenk, Christopher J.

2007-01-01

In 2003, the U.S. Geological Survey (USGS) completed an assessment of the oil and gas resource potential of the San Joaquin Basin Province of California (fig. 1.1). The assessment is based on the geologic elements of each Total Petroleum System defined in the province, including hydrocarbon source rocks (source-rock type and maturation and hydrocarbon generation and migration), reservoir rocks (sequence stratigraphy and petrophysical properties), and hydrocarbon traps (trap formation and timing). Using this geologic framework, the USGS defined five total petroleum systems and ten assessment units within these systems. Undiscovered oil and gas resources were quantitatively estimated for the ten assessment units (table 1.1). In addition, the potential was estimated for further growth of reserves in existing oil fields of the San Joaquin Basin.

Influence of different geological structures on stress–strain state of hard rock mass

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Kuznetzov, NN; Fedotova, YuV

2018-03-01

The results of numerical simulation of stress–strain state in a hard rock mass area with the complex geological structures are presented. The variants of the stress value change are considered depending on the boundary conditions and physical properties of the model blocks. Furthermore, the possibility of in-situ stress formation under the influence of energy coming from the deeper Earth’s layers is demonstrated in terms of the Khibiny Massif.

Rift systems of the Russian Eastern Arctic shelf and Arctic deep water basins: link between geological history and geodynamics

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A. M. Nikishin

2017-01-01

Full Text Available In our study, we have developed a new tectonic scheme of the Arctic Ocean, which is based mainly on seismic profiles obtained in the Arctic-2011, Arctic-2012 and Arctic-2014 Projects implemented in Russia. Having interpreted many seismic profiles, we propose a new seismic stratigraphy of the Arctic Ocean. Our main conclusions are drawn from the interpretation of the seismic profiles and the analysis of the regional geological data. The results of our study show that rift systems within the Laptev, the East Siberian and the Chukchi Seas were formed not earlier than Aptian. The geological structure of the Eurasian, Podvodnikov, Toll and Makarov Basins is described in this paper. Having synthesized all the available data on the study area, we propose the following model of the geological history of the Arctic Ocean: 1. The Canada Basin formed till the Aptian (probably, during Hauterivian-Barremian time. 2. During the Aptian-Albian, large-scale tectonic and magmatic events took place, including plume magmatism in the area of the De Long Islands, Mendeleev Ridge and other regions. Continental rifting started after the completion of the Verkhoyansk-Chukotka orogenу, and rifting occurred on the shelf of the Laptev, East Siberian, North Chukchi and South Chukchi basins, and the Chukchi Plateau; simultaneously, continental rifting started in the Podvodnikov and Toll basins. 3. Perhaps the Late Cretaceous rifting continued in the Podvodnikov and Toll basins. 4. At the end of the Late Cretaceous and Paleocene, the Makarov basin was formed by rifting, although local spreading of oceanic crust during its formation cannot be excluded. 5. The Eurasian Basin started to open in the Early Eocene. We, of course, accept that our model of the geological history of the Arctic Ocean, being preliminary and debatable, may need further refining. In this paper, we have shown a link between the continental rift systems on the shelf and the formation history of the Arctic

Integrated geophysical survey for the geological structural and hydrogeothermal study of the North-western Gargano promontory (Southern Italy

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D. Schiavone

1996-06-01

Full Text Available A multimethodological geophysical survey was performed in the north-western part of the Gargano promontory to study the geological structural setting and the underground fluid flow characteristics. The area has a complex tectonics with some magmatic outcrops and shallow low-enthalpy waters. Electrical, seismic reflection, gravimetric and magnetic surveys were carried out to reconstruct the geological structures; and in order to delineate the hydrogeothermal characteristics of the area, the self-potential survey was mainly used. Moreover magnetic and self-potential measurements were also performed in the Lesina lake. The joint three-dimensional interpretation of the geophysical data disclosed a large horst and graben structure covering a large part of the area. In the central part of the horst a large ramified volcanic body was modelled. The models show some intrusions rising from it to or near to the surface. The main structures are well deep-seated in the Crust and along them deep warm fluids rise as the SP data interpretation indicates.

Analysis on sequence stratigraphy and depositional systems of Mangbang formation, upper tertiary in Longchuanjiang basin

International Nuclear Information System (INIS)

Sun Zexuan; Yao Yifeng; Chen Yong; Li Guoxin

2004-01-01

Longchuanjiang basin is a small Cenozoic intramontane down-faulted basin. This paper, combining the Pliocene structure, the volcanic activities and the sedimentation of the basin, analyses the sequence stratigraphy and the depositional systems of Mangbang formation (the cover of the basin). Based on the analysis of depositional systems of Mangbang formation, the depositional pattern of Pliocene in Longchuanjiang basin is set up. It is suggested that because of the fast accumulation in early down-faulted zone during Pliocene time, the alluvial fan depositional system was dominated at that time. During the middle-late period, the alluvial fan entered the lake forming a combination of fan-fandelta-lacustrine depositional systems. Authors propose a view point that the formation of Mangbang formation sequence was constrained by multistage tectonic movement, and three structural sequences were established, and system tracts were divided. (authors)

Mapping Geological Structures In Wadi Ghoweibaarea, Northwest Gulf Of Suez, Egypt, Using Aster-Spot Data Fusion And Aster DEM

International Nuclear Information System (INIS)

Abdeen, M.M.; Hassan, S.M.; EL-Kazzaz, Y.A.H.A.; Attia, G.M.; Yehia, M.A.

2009-01-01

Practical and economical constraints prompt the need of obtaining lithological and structural information for development of desert areas with reduced field effort. The fusion of multi-sensor satellite data is an effective mean of exploiting the complimentary nature of different data types. This technique allows fusion of spectral-spectral information of multi-source data with high accuracy. In the present study, fusion of SPOT and ASTER data was applied to test the potentiality of this technique in mapping geological formations and structural lineaments in Wadi Ghoweiba area, to the west of the northwestern tip of the Gulf of Suez, Egypt. ASTER data is characterized by a wide range of spectral bands (14 bands), while SPOT panchromatic data is characterized by high (10 meters) spatial resolution. Based on spectral characteristic analysis (SCA) of the 3 VNIR and the 6 SWIR bands of ASTER data, two false-color band-ratio images (1/3, 2/5, and 4/ 9) and (1/5, 8/9, and 4/6) in R, G, B were produced for better lithological discrimination. SPOT panchromatic image data was fused with ASTER band ratio images data using principal component (PC) and color normalization or Brovey transformation techniques. The fused images proved to be excellent for lithological discrimination. ASTER data includes bands 3N (Nadir) and 3B (Backward) that are acquired in the spectral range of near infrared region (from 0.78 to 0.86 microns) allowing extraction of digital elevation model (DEM). Three-dimensional perspective views were generated by draping SPOT-ASTER ratio fused images over ASTER DEM. This technique was used to enhance morphologically-defined structures. The fused images and the 3D perspective views were interpreted to produce a photo geological-structural map that was verified using the available geological maps and subsequent field check. The produced photo geological map indicates that fusion of SPOT and ASTER ratio image's data is a reliable technique for geological mapping

Use of high-resolution satellite images for detection of geological structures related to Calerias geothermal field, Chile

Science.gov (United States)

Arellano-Baeza, A. A.; Urzua, L.

2011-12-01

Chile has enormous potential to use the geothermal resources for electric energy generation. The main geothermal fields are located in the Central Andean Volcanic Chain in the North, between the Central valley and the border with Argentina in the center, and in the fault system Liquiñe-Ofqui in the South of the country. High resolution images from the LANDSAT and ASTER satellites have been used to delineate the geological structures related to the Calerias geothermal field located at the northern end of the Southern Volcanic Zone of Chile. It was done by applying the lineament extraction technique developed by authors. These structures have been compared with the distribution of main geological structures obtained in the field. It was found that the lineament density increases in the areas of the major heat flux indicating that the lineament analysis could be a power tool for the detection of faults and joint zones associated to the geothermal fields.

Development of JNC geological disposal technical information integration system for geological environment field

International Nuclear Information System (INIS)

Tsuchiya, Makoto; Ueta, Shinzo; Ohashi, Toyo

2004-02-01

Enormous data on geology, geological structure, hydrology, geochemistry and rock properties should be obtained by various investigation/study in the geological disposal study. Therefore, 'JNC Geological Disposal Technical Information Integration System for Geological Environment Field' was developed in order to manage these data systematically and to support/promote the use of these data for the investigators concerned. The system is equipped with data base to store the information of the works and the background information of the assumptions built up in the works on each stage of data flow ('instigative', → 'data sampling' → interpretation' → conceptualization/modeling/simulation' → 'output') in the geological disposal study. In this system the data flow is shown as 'plan' composed of task' and 'work' to be done in the geological disposal study. It is possible to input the data to the database and to refer data from the database by using GUI that shows the data flow as 'plan'. The system was installed to the server computer possessed by JNC and the system utilities were checked on both the server computer and client computer also possessed by JNC. (author)

Geophysical investigations of geology and structure at the Martis Creek Dam, Truckee, California

Science.gov (United States)

Bedrosian, P.A.; Burton, B.L.; Powers, M.H.; Minsley, B.J.; Phillips, J.D.; Hunter, L.E.

2012-01-01

A recent evaluation of Martis Creek Dam highlighted the potential for dam failure due to either seepage or an earthquake on nearby faults. In 1972, the U.S. Army Corps of Engineers constructed this earthen dam, located within the Truckee Basin to the north of Lake Tahoe, CA for water storage and flood control. Past attempts to raise the level of the Martis Creek Reservoir to its design level have been aborted due to seepage at locations downstream, along the west dam abutment, and at the base of the spillway. In response to these concerns, the U.S. Geological Survey has undertaken a comprehensive suite of geophysical investigations aimed at understanding the interplay between geologic structure, seepage patterns, and reservoir and groundwater levels. This paper concerns the geologic structure surrounding Martis Creek Dam and emphasizes the importance of a regional-scale understanding to the interpretation of engineering-scale geophysical data. Our studies reveal a thick package of sedimentary deposits interbedded with Plio-Pleistocene volcanic flows; both the deposits and the flows are covered by glacial outwash. Magnetic field data, seismic tomography models, and seismic reflections are used to determine the distribution and chronology of the volcanic flows. Previous estimates of depth to basement (or the thickness of the interbedded deposits) was 100 m. Magnetotelluric soundings suggest that electrically resistive bedrock may be up to 2500 m deep. Both the Polaris Fault, identified outside of the study area using airborne LiDAR, and the previously unnamed Martis Creek Fault, have been mapped through the dam area using ground and airborne geophysics. Finally, as determined by direct-current resistivity imaging, time-domain electromagnetic sounding, and seismic refraction, the paleotopography of the interface between the sedimentary deposits and the overlying glacial outwash plays a principal role both in controlling groundwater flow and in the distribution of the

Study of geologic-structural situation around Semipalatinsk test site test - holes using space images automated decoding method

International Nuclear Information System (INIS)

Gorbunova, Eh.M.; Ivanchenko, G.N.

2004-01-01

Performance of underground nuclear explosions (UNE) leads to irreversible changes in geological environment around the boreholes. In natural environment it was detected inhomogeneity of rock massif condition changes, which depended on characteristics of the underground nuclear explosion, anisotropy of medium and presence of faulting. Application of automated selection and statistic analysis of unstretched lineaments in high resolution space images using special software pack LESSA allows specifying the geologic-structural features of Semipalatinsk Test Site (STS), ranging selected fracture zones, outlining and analyzing post-explosion zone surface deformations. (author)

Changing concepts of geologic structure and the problem of siting nuclear reactors: examples from Washington State

International Nuclear Information System (INIS)

Tabor, R.W.

1986-01-01

The conflict between regulation and healthy evolution of geological science has contributed to the difficulties of siting nuclear reactors. On the Columbia Plateau in Washington, but for conservative design of the Hanford reactor facility, the recognition of the little-understood Olympic-Wallowa lineament as a major, possibly still active structural alignment might have jeopardized the acceptability of the site for nuclear reactors. On the Olympic Peninsula, evolving concepts of compressive structures and their possible recent activity and the current recognition of a subducting Juan de Fuca plate and its potential for generating great earthquakes - both concepts little-considered during initial site selection - may delay final acceptance of the Satsop site. Conflicts of this sort are inevitable but can be accommodated if they are anticipated in the reactor-licensing process. More important, society should be increasing its store of geologic knowledge now, during the current recess in nuclear reactor siting

Earth History databases and visualization - the TimeScale Creator system

Science.gov (United States)

Ogg, James; Lugowski, Adam; Gradstein, Felix

2010-05-01

The "TimeScale Creator" team (www.tscreator.org) and the Subcommission on Stratigraphic Information (stratigraphy.science.purdue.edu) of the International Commission on Stratigraphy (www.stratigraphy.org) has worked with numerous geoscientists and geological surveys to prepare reference datasets for global and regional stratigraphy. All events are currently calibrated to Geologic Time Scale 2004 (Gradstein et al., 2004, Cambridge Univ. Press) and Concise Geologic Time Scale (Ogg et al., 2008, Cambridge Univ. Press); but the array of intercalibrations enable dynamic adjustment to future numerical age scales and interpolation methods. The main "global" database contains over 25,000 events/zones from paleontology, geomagnetics, sea-level and sequence stratigraphy, igneous provinces, bolide impacts, plus several stable isotope curves and image sets. Several regional datasets are provided in conjunction with geological surveys, with numerical ages interpolated using a similar flexible inter-calibration procedure. For example, a joint program with Geoscience Australia has compiled an extensive Australian regional biostratigraphy and a full array of basin lithologic columns with each formation linked to public lexicons of all Proterozoic through Phanerozoic basins - nearly 500 columns of over 9,000 data lines plus hot-curser links to oil-gas reference wells. Other datapacks include New Zealand biostratigraphy and basin transects (ca. 200 columns), Russian biostratigraphy, British Isles regional stratigraphy, Gulf of Mexico biostratigraphy and lithostratigraphy, high-resolution Neogene stable isotope curves and ice-core data, human cultural episodes, and Circum-Arctic stratigraphy sets. The growing library of datasets is designed for viewing and chart-making in the free "TimeScale Creator" JAVA package. This visualization system produces a screen display of the user-selected time-span and the selected columns of geologic time scale information. The user can change the

Presumption of the distribution of the geological structure based on the geological survey and the topographic data in and around the Horonobe area

International Nuclear Information System (INIS)

Sakai, Toshihiro; Matsuoka, Toshiyuki

2015-06-01

The Horonobe Underground Research Laboratory (URL) Project, a comprehensive research project investigating the deep underground environment in sedimentary rock, is being pursued by the Japan Atomic Energy Agency (JAEA) at Horonobe-cho in Northern Hokkaido, Japan. One of the main goals of the URL project is to establish techniques for investigation, analysis and assessment of the deep geological environment. JAEA constructed the geologic map and the database of geological mapping in Horonobe-cho in 2005 based on the existing literatures and 1/200,000 geologic maps published by Geological Survey of Japan, and then updated the geologic map in 2007 based on the results of various investigations which were conducted around the URL as the surface based investigation phase of the URL project. On the other hand, there are many geological survey data which are derived from natural resources (petroleum, natural gas and coal, etc.) exploration in and around Horonobe-cho. In this report, we update the geologic map and the database of the geological mapping based on these geological survey and topographical analysis data in and around the Horonobe area, and construct a digital geologic map and a digital database of geological mapping as GIS. These data can be expected to improve the precision of modeling and analyzing of geological environment including its long-term evaluation. The digital data is attached on CD-ROM. (J.P.N.)

Geological Geophysical and structural studies in Mina Ratones (Pluton de Albala); Estudios geologico-estructurales y geofisicos en Mina Ratones (Pluton de Albala)

Energy Technology Data Exchange (ETDEWEB)

Perez-Estaun, A; Carbonell, R; Marti, D; Flecha, I [Instituto de Ciencias de la Tierra Jaume Almera. Barcelona (Spain); Escuder Viruete, J [Universidad complutense de Madrid. Madrid (Spain)

2002-07-01

Mina Ratones environmental restoration project included petrological, structural,geophysical, hydrogeological and hydrogeochemical studies. The main objective of the geologic-structural and geophysical studies was the Albala granite structural characterization around the Mina Ratones uranium mine. The location of facies, fault zones (faults and dykes) as well as the distribution of some physical properties inside the rock massif was obtained for a granitic black of 900, 500, and 500 m. The geologic-structural and geophysical techniques applied to Mina Ratones provided a multidisciplinary approach for high resolution characterization of rock massif, and the structures potentially containing fluids,able to be applied to the hydrogeological modelling to a particular area. Geological studies included a detailed structural mapping of the area surrounding the mine (1:5,000 scale), the geometric, kinematics, and dynamics analysis of fractures of all scales, the petrology and geochemistry of fault rocks and altered areas surrounding fractures, and the microstructural studies of samples from surface and core lags. The construction of geostatistical models in two and three dimensions had helped to characterize the Mina Ratones rock massif showing the spatial distribution of fault zones, fracture intensity, granite composition heterogeneities, fluid-rock interaction zones, and physical properties. (Author)

[Usefulness of stratigraphy and computerized tomography in the initial staging of osteosarcoma of the extremities. Retrospective study of 217 cases].

Science.gov (United States)

Pelotti, P; Ciminari, R; Bacci, G; Avella, M; Briccoli, A

1988-01-01

The value of stratigraphy and pulmonary CT in the initial work-up of osteosarcoma of the extremities is assessed with reference to 217 patients encountered in the Bone Tumour Centre of Rizzoli Orthopaedic Institute in May 1983-May 1986. Stratigraphy revealed lung metastases not identified by standard radiography in 4 patients (1.8%), while CT revealed metastases not identified by either standard X-rays or stratigraphy in a further 6 cases (2.7%). It is concluded that the increase in the percentage of cures (about 30%) reported in the last 10 years in osteosarcoma cases given adjuvant chemotherapy cannot be explained by any difference in initial selection due to the use of these techniques that were not adopted in the historical series.

Petroleum systems and geologic assessment of undiscovered oil and gas, Cotton Valley group and Travis Peak-Hosston formations, East Texas basin and Louisiana-Mississippi salt basins provinces of the northern Gulf Coast region. Chapters 1-7.

Science.gov (United States)

,

2006-01-01

The purpose of the U.S. Geological Survey's (USGS) National Oil and Gas Assessment is to develop geologically based hypotheses regarding the potential for additions to oil and gas reserves in priority areas of the United States. The USGS recently completed an assessment of undiscovered oil and gas potential of the Cotton Valley Group and Travis Peak and Hosston Formations in the East Texas Basin and Louisiana-Mississippi Salt Basins Provinces in the Gulf Coast Region (USGS Provinces 5048 and 5049). The Cotton Valley Group and Travis Peak and Hosston Formations are important because of their potential for natural gas resources. This assessment is based on geologic principles and uses the total petroleum system concept. The geologic elements of a total petroleum system include hydrocarbon source rocks (source rock maturation, hydrocarbon generation and migration), reservoir rocks (sequence stratigraphy and petrophysical properties), and hydrocarbon traps (trap formation and timing). The USGS used this geologic framework to define one total petroleum system and eight assessment units. Seven assessment units were quantitatively assessed for undiscovered oil and gas resources.

Mapping urban geology of the city of Girona, Catalonia

Science.gov (United States)

Vilà, Miquel; Torrades, Pau; Pi, Roser; Monleon, Ona

2016-04-01

A detailed and systematic geological characterization of the urban area of Girona has been conducted under the project '1:5000 scale Urban geological map of Catalonia' of the Catalan Geological Survey (Institut Cartogràfic i Geològic de Catalunya). The results of this characterization are organized into: i) a geological information system that includes all the information acquired; ii) a stratigraphic model focused on identification, characterization and correlation of the geological materials and structures present in the area and; iii) a detailed geological map that represents a synthesis of all the collected information. The mapping project integrates in a GIS environment pre-existing cartographic documentation (geological and topographical), core data from compiled boreholes, descriptions of geological outcrops within the urban network and neighbouring areas, physico-chemical characterisation of representative samples of geological materials, detailed geological mapping of Quaternary sediments, subsurface bedrock and artificial deposits and, 3D modelling of the main geological surfaces. The stratigraphic model is structured in a system of geological units that from a chronostratigrafic point of view are structured in Palaeozoic, Paleogene, Neogene, Quaternary and Anthropocene. The description of the geological units is guided by a systematic procedure. It includes the main lithological and structural features of the units that constitute the geological substratum and represents the conceptual base of the 1:5000 urban geological map of the Girona metropolitan area, which is organized into 6 map sheets. These map sheets are composed by a principal map, geological cross sections and, several complementary maps, charts and tables. Regardless of the geological map units, the principal map also represents the main artificial deposits, features related to geohistorical processes, contours of outcrop areas, information obtained in stations, borehole data, and contour

Holocene stratigraphy and vegetation history in the Scoresby Sund area, East Greenland

DEFF Research Database (Denmark)

Funder, Svend Visby

1978-01-01

The Holocene stratigraphy in Scoresby Sund is based on climatic change as reflected by fluctuations in fjord and valley glaciers, immigration and extinction of marine molluscs, and the vegetation history recorded in pollen diagrams from five lakes. The histories are dated by C-14, and indirectly...

Stratigraphy and Folding in the Cenozoic Cover of a Fold-Thrust Belt in the Nallıhan Region (Ankara, Central Turkey)

Science.gov (United States)

Karaaǧaç, Serdal; Koral, Hayrettin

2017-04-01

This study investigates stratigraphy and structural features in the Cenozoic sedimentary sequence of the fold-thrust belt of the Nallıhan-Ankara region, located to the north of the İzmir-Ankara-Erzincan Suture Zone. Permian-Triassic age marble intercalated with schist-phyllites, the upper Jurassic-lower Cretaceous age limestone and the upper Cretaceous age sandstone-shale alternation compose the basement in the study area. These rocks are unconformably overlain by the Cenozoic age terrestrial sedimentary and volcanic units. The Cenozoic stratigraphy begins with the Paleocene-Eocene age coal-bearing, at times, volcanic intercalated conglomerate-sandstone-mudstone alternation of alluvial-fluvial origins (Aksaklar Formation) and the tuff intercalated with lacustrine limestone, bituminous limestone (Kabalar Formation). These units are conformably overlain by the Eocene age basalt-andesite and pyroclastic rocks (Meyildere volcanics). The Paleocene-Eocene aged units are unconformably overlain by the conglomerate-sandstone-mudstone-marl of a lower-middle Miocene lacustrine environment (Hançili Formation). The terrestrial conglomerate-sandstone alternation (Örencik Formation) is the youngest unit in the Cenozoic stratigraphy, and is assumed to be of Pliocene age based its stratigraphic position on older units. Field study shows existence of both folds and faults in the sedimentary cover. Stereographic projections of bedding measured in the field shows N25W/45NW and N60W/4SE-oriented fold axes in the Paleocene-Eocene age units. There are also N76W/12SE and N88E/8NE-oriented folds. The difference in fold-axis orientations suggests that some folds may have been rotated in blocks bound by faults during the post-Paleocene/Eocene period. Whereas, the lower-middle Miocene units manifest N88W/13SE-oriented fold axes. It is thus proposed that the observed difference in the azimuth of fold axes represent two different folding phases, one with NE-SW and the other with N

HCMM: Soil moisture in relation to geologic structure and lithology, northern California

Science.gov (United States)

Rich, E. I. (Principal Investigator)

1981-01-01

Some HCMM images of about 80,000 sq km in northern California were qualitatively evaluated for usefulness in regional geologic investigations of structure and lithology. The thermal characteristics recorded vary among the several geomorphic provinces and depends chiefly on the topographic expression and vegetation cover. Identification of rock types, or groups of rock types, was most successfully carried out within the semi-arid parts of the region; however, extensive features, such as faults, folds and volcanic fields could be delineated. Comparisons of seasonally obtained HCMM images were limited value, except in semi-arid regions.

Geologic character of tuffs in the unsaturated zone at Yucca Mountain, southern Nevada

International Nuclear Information System (INIS)

Scott, R.B.; Spengler, R.W.; Diehl, S.; Lappin, A.R.; Chornack, M.P.

1982-01-01

At Yucca Mountain, a potential site for a high-level nuclear waste repository on the Nevada Test Site in southern Nevada, evaluation of the geologic setting and rock physical properties, along with previous regional hydrologic studies, has provided background that can be used for construction of a preliminary conceptual hydrologic model of the unsaturated zone. The 500-m-thick unsaturated portion of Yucca Mountain consists of alternating layers of two contrasting types of tuff. One type consists of highly fractured, densely welded, relatively nonporous but highly transmissive ash-flow tuffs. The other type consists of relatively unfractured, nonwelded, highly porous but relatively nontransmissive, argillic and zeolitic bedded tuffs and ash-flow tuffs. The contrast between these two sets of distinctive physical properties results in a stratified sequence best described as ''physical-property stratigraphy'' as opposed to traditional petrologic stratigraphy of volcanic rocks. The vast majority of recharge through the unsaturated zone is assumed to be vertical; the dominant migration may occur in fractures of densely welded tuffs and in the matrix of nonwelded tuff, but the mode of fluid flow in these unsaturated systems is undetermined. Limited lateral flow of recharge may occur at horizons where local perched water tables may exist above relatively nontransmissive zeolitized nonwelded tuffs. The pervasive north-northwest-striking fractures may control the direction of lateral flow of recharge, if any, in the unsaturated zone, and certainly that direction coincides closely with the observed southeasterly flow direction in the saturated zone under Yucca Mountain. Empirical evaluation of this conceptual hydrologic model has begun. 41 refs., 18 figs., 2 tabs

Geologic character of tuffs in the unsaturated zone at Yucca Mountain, southern Nevada

Energy Technology Data Exchange (ETDEWEB)

Scott, R.B.; Spengler, R.W.; Diehl, S.; Lappin, A.R.; Chornack, M.P.

1982-12-31

At Yucca Mountain, a potential site for a high-level nuclear waste repository on the Nevada Test Site in southern Nevada, evaluation of the geologic setting and rock physical properties, along with previous regional hydrologic studies, has provided background that can be used for construction of a preliminary conceptual hydrologic model of the unsaturated zone. The 500-m-thick unsaturated portion of Yucca Mountain consists of alternating layers of two contrasting types of tuff. One type consists of highly fractured, densely welded, relatively nonporous but highly transmissive ash-flow tuffs. The other type consists of relatively unfractured, nonwelded, highly porous but relatively nontransmissive, argillic and zeolitic bedded tuffs and ash-flow tuffs. The contrast between these two sets of distinctive physical properties results in a stratified sequence best described as "physical-property stratigraphy" as opposed to traditional petrologic stratigraphy of volcanic rocks. The vast majority of recharge through the unsaturated zone is assumed to be vertical; the dominant migration may occur in fractures of densely welded tuffs and in the matrix of nonwelded tuff, but the mode of fluid flow in these unsaturated systems is undetermined. Limited lateral flow of recharge may occur at horizons where local perched water tables may exist above relatively nontransmissive zeolitized nonwelded tuffs. The pervasive north-northwest-striking fractures may control the direction of lateral flow of recharge, if any, in the unsaturated zone, and certainly that direction coincides closely with the observed southeasterly flow direction in the saturated zone under Yucca Mountain. Empirical evaluation of this conceptual hydrologic model has begun. 41 refs., 18 figs., 2 tabs.

Geology of Cardiff and Faraday Townships

Energy Technology Data Exchange (ETDEWEB)

Hewitt, D F

1960-12-31

The area described in this report lies at the centre of the Haliburton-Bancroft uranium district in Ontario, where prospecting and mining have been carried out for over 50 years. The report describes the area`s physiography, natural resources, general geology (Precambrian metasedimentary, plutonic, and granitic and syenitic rocks), structural geology, and economic geology. The latter section includes descriptions of occurrences, claims, mines, and mineral properties, including the principal uranium properties in the area.

Stratigraphy of the Anthropocene.

Science.gov (United States)

Zalasiewicz, Jan; Williams, Mark; Fortey, Richard; Smith, Alan; Barry, Tiffany L; Coe, Angela L; Bown, Paul R; Rawson, Peter F; Gale, Andrew; Gibbard, Philip; Gregory, F John; Hounslow, Mark W; Kerr, Andrew C; Pearson, Paul; Knox, Robert; Powell, John; Waters, Colin; Marshall, John; Oates, Michael; Stone, Philip

2011-03-13

The Anthropocene, an informal term used to signal the impact of collective human activity on biological, physical and chemical processes on the Earth system, is assessed using stratigraphic criteria. It is complex in time, space and process, and may be considered in terms of the scale, relative timing, duration and novelty of its various phenomena. The lithostratigraphic signal includes both direct components, such as urban constructions and man-made deposits, and indirect ones, such as sediment flux changes. Already widespread, these are producing a significant 'event layer', locally with considerable long-term preservation potential. Chemostratigraphic signals include new organic compounds, but are likely to be dominated by the effects of CO(2) release, particularly via acidification in the marine realm, and man-made radionuclides. The sequence stratigraphic signal is negligible to date, but may become geologically significant over centennial/millennial time scales. The rapidly growing biostratigraphic signal includes geologically novel aspects (the scale of globally transferred species) and geologically will have permanent effects.

Geologic Setting and Preservation of a Late Pleistocene Bald Cypress Forest Discovered on the Northern Gulf of Mexico Continental Shelf

Science.gov (United States)

Gonzalez Rodriguez, S. M.; Bentley, S. J.; DeLong, K. L.; Xu, K.; Harley, G. L.; Reese, C. A.; Obelcz, J.

2016-02-01

Following landfall of Hurricane Ivan in 2004, a previously buried bald cypress forest (Taxodium distichum) was discovered on the continental shelf seafloor, offshore of Orange Beach, Alabama, USA, in 20 m of water. The forest is preserved as stumps in life position with little evidence of decay and large pieces of trunks, roots, and branches. Analysis shows the forest is older than can be dated with conventional C-14 methods. Comparison of Pleistocene sea level curves with the study area depth suggests that the forest developed and was likely buried during marine isotope stage 3 or 4, or perhaps older stages. Condition of sampled wood suggests that the forest was buried and preserved in anoxic sediments for millennia, prior to recent exhumation. To better understand the puzzling geological conditions that could allow forest preservation during sea level fall and shelf exposure spanning >30,000 years, submersible vibracores (to 6 m length) and geophysical data (swath bathymetry, sidescan, and chirp subbottom) were collected in August 2015. Cores are being analyzed using a Geotek Multi Sensor Core Logger, granulometric and sediment composition analyses, and a wide range of paleoenvironmental observations. This presentation focuses on the geological setting and mode of forest preservation. Preliminary analysis of sediment types and stratigraphy in cores shows that the local stratigraphy is broadly consistent with previous regional shelf-stratigraphic studies, consisting of (top to bottom) a surface layer of Holocene transgressive sands (to 3 m thick) unconformably overlying Pleistocene terrestrial and coastal deposits. However, the Pleistocene lithofacies (fluvial, backswamp, or possibly delta plain muds) differ considerably in both depositional environment and degree of environmental preservation compared to previous studies. Ongoing analysis will focus on elucidating the succession of events that allows preservation of this unique Pleistocene sedimentary archive.

The Beaverhead impact structure, SW Montana and Idaho: Implications for the regional geology of the western U.S.

Energy Technology Data Exchange (ETDEWEB)

Fiske, P.S.; Hargaves, R.B.

1994-03-17

The Beaverhead impact structure in SW Montana and Idaho is an allochthonous fragment of a large impact structure ({approximately} 100 km diameter) that was transported some distance eastward during the Cretaceous Sevier orogeny. It is the first tectonic fragment of a large impact structure identified in the geologic record. The present evidence for impact consists of shatter cones, pseudotachylites, and planar deformation features in quartz. The age of the impact is not well constrained but is estimated to be Neoproterozoic to Cambrian (1000-500 Ma). The Beaverhead impact event must have created other features that may be preserved, elsewhere in western Montana and Idaho. These include proximal and distal ejecta (which may be misinterpreted as diamictites and/or tuff horizons) and other fragments of the crater floor containing shatter cones and pseudotachylite. A large circular gravity, magnetic and topographic anomaly, which could be the root of the impact structure, has been identified near Challis, Idaho. An enigmatic lithic tuff, identified in drill cores from the Challis area and an intraformational quartzite breccia in the Leaton Gulch area may be impact-related deposits, but no definitive evidence of shock metamorphism has been observed in these materials. The discovery of more pieces of the Beaverhead puzzle, as well as the recognition of other large impacts in the geologic record, are likely once the regional geologic community grows to accept the incidence of such events and becomes more familiar with the features of shock metamorphism in the field. To that end, the community of geologists in this area should integrate the Beaverhead structure into their research and teaching curriculum.

Geology and potential of the formation of sandstone type uranium mineralization at Hatapang region, North Sumatera

International Nuclear Information System (INIS)

Ngadenin

2013-01-01

The Study based on geological setting of Hatapang region, North Sumatera, identified as a favourable area to the formation of sandstone type uranium mineralization. This characterized by the occurred of anomalous radioactivity, uranium contents of the upper cretaceous granite intrusions and radioactivity anomalous of tertiary sedimentary rocks deposited in terrestrial environments. The study is objective to find out the potential formation of sandstone type-uranium mineralization within tertiary sedimentary rocks based on data’s studies of geological, geochemical, mineralogy, radioactivity of rocks. Stratigraphy of Hatapang area of the oldest to youngest are quartz units (permian-carboniferous), sandstone units (upper Triassic), granite (upper cretaceous), conglomerate units (Lower –middle Miocene) and tuff units (Pleistocene). Hatapang’s granite is S type granite which is not only potential as source of radioactive minerals, particularly placer type monazite, but also potential as source rocks of sandstone type-uranium mineralization on lighter sedimentary rocks. Sedimentary rock of conglomerate units has potential as host rock, even though uranium did not accumulated in its rocks since the lack number of carbon as precipitant material and dissolved U"+"6 in water did not reduced into U"+"4 caused the uranium mineralization did not deposited. (author)

Geological-structural models used in SR 97. Uncertainty analysis

Energy Technology Data Exchange (ETDEWEB)

Saksa, P.; Nummela, J. [FINTACT Oy (Finland)

1998-10-01

The uncertainty of geological-structural models was studied for the three sites in SR 97, called Aberg, Beberg and Ceberg. The evaluation covered both regional and site scale models, the emphasis being placed on fracture zones in the site scale. Uncertainty is a natural feature of all geoscientific investigations. It originates from measurements (errors in data, sampling limitations, scale variation) and conceptualisation (structural geometries and properties, ambiguous geometric or parametric solutions) to name the major ones. The structures of A-, B- and Ceberg are fracture zones of varying types. No major differences in the conceptualisation between the sites were noted. One source of uncertainty in the site models is the non-existence of fracture and zone information in the scale from 10 to 300 - 1000 m. At Aberg the development of the regional model has been performed very thoroughly. At the site scale one major source of uncertainty is that a clear definition of the target area is missing. Structures encountered in the boreholes are well explained and an interdisciplinary approach in interpretation have taken place. Beberg and Ceberg regional models contain relatively large uncertainties due to the investigation methodology and experience available at that time. In site scale six additional structures were proposed both to Beberg and Ceberg to variant analysis of these sites. Both sites include uncertainty in the form of many non-interpreted fractured sections along the boreholes. Statistical analysis gives high occurrences of structures for all three sites: typically 20 - 30 structures/km{sup 3}. Aberg has highest structural frequency, Beberg comes next and Ceberg has the lowest. The borehole configuration, orientations and surveying goals were inspected to find whether preferences or factors causing bias were present. Data from Aberg supports the conclusion that Aespoe sub volume would be an anomalously fractured, tectonised unit of its own. This means that

Geological-structural models used in SR 97. Uncertainty analysis

International Nuclear Information System (INIS)

Saksa, P.; Nummela, J.

1998-10-01

The uncertainty of geological-structural models was studied for the three sites in SR 97, called Aberg, Beberg and Ceberg. The evaluation covered both regional and site scale models, the emphasis being placed on fracture zones in the site scale. Uncertainty is a natural feature of all geoscientific investigations. It originates from measurements (errors in data, sampling limitations, scale variation) and conceptualisation (structural geometries and properties, ambiguous geometric or parametric solutions) to name the major ones. The structures of A-, B- and Ceberg are fracture zones of varying types. No major differences in the conceptualisation between the sites were noted. One source of uncertainty in the site models is the non-existence of fracture and zone information in the scale from 10 to 300 - 1000 m. At Aberg the development of the regional model has been performed very thoroughly. At the site scale one major source of uncertainty is that a clear definition of the target area is missing. Structures encountered in the boreholes are well explained and an interdisciplinary approach in interpretation have taken place. Beberg and Ceberg regional models contain relatively large uncertainties due to the investigation methodology and experience available at that time. In site scale six additional structures were proposed both to Beberg and Ceberg to variant analysis of these sites. Both sites include uncertainty in the form of many non-interpreted fractured sections along the boreholes. Statistical analysis gives high occurrences of structures for all three sites: typically 20 - 30 structures/km 3 . Aberg has highest structural frequency, Beberg comes next and Ceberg has the lowest. The borehole configuration, orientations and surveying goals were inspected to find whether preferences or factors causing bias were present. Data from Aberg supports the conclusion that Aespoe sub volume would be an anomalously fractured, tectonised unit of its own. This means that the

Correlation of the Eemian (interglacial) Stage and the deep-sea oxygen-isotope stratigraphy

International Nuclear Information System (INIS)

Mangerud, J.; Soenstegaard, E.; Sejrup, H.-P.

1979-01-01

A complete interglacial sequence in coastal marine sediments in western Norway is here correlated with the Eemian Stage by means of pollen stratigraphy, and with deep-sea cores by means of marine fossils. The Eemian is correlated with isotope stage 5e. (author)

OneGeology - Access to geoscience for all

Science.gov (United States)

Komac, Marko; Lee, Kathryn; Robida, Francois

2014-05-01

OneGeology is an initiative of Geological Survey Organisations (GSO) around the globe that dates back to Brighton, UK in 2007. Since then OneGeology has been a leader in developing geological online map data using a new international standard - a geological exchange language known as 'GeoSciML'. Increased use of this new language allows geological data to be shared and integrated across the planet with other organisations. One of very important goals of OneGeology was a transfer of valuable know-how to the developing world, hence shortening the digital learning curve. In autumn 2013 OneGeology was transformed into a Consortium with a clearly defined governance structure, making its structure more official, its operability more flexible and its membership more open where in addition to GSO also to other type of organisations that manage geoscientific data can join and contribute. The next stage of the OneGeology initiative will hence be focused into increasing the openness and richness of that data from individual countries to create a multi-thematic global geological data resource on the rocks beneath our feet. Authoritative information on hazards and minerals will help to prevent natural disasters, explore for resources (water, minerals and energy) and identify risks to human health on a planetary scale. With this new stage also renewed OneGeology objectives were defined and these are 1) to be the provider of geoscience data globally, 2) to ensure exchange of know-how and skills so all can participate, and 3) to use the global profile of 1G to increase awareness of the geosciences and their relevance among professional and general public. We live in a digital world that enables prompt access to vast amounts of open access data. Understanding our world, the geology beneath our feet and environmental challenges related to geology calls for accessibility of geoscientific data and OneGeology Portal (portal.onegeology.org) is the place to find them.

The geology of Piz Pian Grand

International Nuclear Information System (INIS)

Huber, M.; Staeuble, J.

1987-01-01

Nagra has identified four potential sites for a repository for low- and intermediate-level waste. Exploration work is already underway at Oberbauenstock (UR) and Piz Pian Grand (GR). As part of the investigations in the Piz Pian Grand area, geological surface mapping was carried out between 1984 and 1987. Since the data obtained is still being evaluated, it would be premature to draw any interpretative conclusions at this stage. On the other hand, some of the most significant observations of this work can be summarised here. As a first step, the geological framework in which these investigations are to be seen should be defined. Observations will then be made on the rock content (lithology) and geometric structure (structural geology) of the area. (author) 6 figs

SAR Tomography for Terrestrial Snow Stratigraphy

Science.gov (United States)

Lei, Y.; Xu, X.; Baldi, C.; Bleser, J. W. D.; Yueh, S. H.; Elder, K.

2017-12-01

Traditional microwave observation of snowpack includes brightness temperature and backscatter. The single baseline configuration and loss of phase information hinders the retrieval of snow stratigraphy information from microwave observations. In this paper, we are investigating the tomography of polarimetric SAR to measure snow stratigraphy. In the past two years, we have developed a homodyne frequency modulated continuous wave radar (FMCW), operation at three earth exploration satellite bands within the X-band and Ku-band spectrums (centered at 9.6 GHz, 13.5 GHz, and 17.2 GHz) at Jet Propulsion Laboratory. The transceiver is mounted to a dual-axis planar scanner (60cm in each direction), which translates the antenna beams across the target area creating a tomographic baseline in two directions. Dual-antenna architecture was implemented to improve the isolation between the transmitter and receiver. This technique offers a 50 dB improvement in signal-to-noise ratio versus conventional single-antenna FMCW radar systems. With current setting, we could have around 30cm vertical resolution. The system was deployed on a ground based tower at the Fraser Experimental Forest (FEF) Headquarters, near Fraser, CO, USA (39.847°N, 105.912°W) from February 1 to April 30, 2017 and run continuously with some gaps for required optional supports. FEF is a 93-km2 research watershed in the heart of the central Rocky Mountains approximately 80-km West of Denver. During the campaign, in situ measurements of snow depth and other snowpack properties were performed every week for comparison with the remotely sensed data. A network of soil moisture sensors, time-lapse cameras, acoustic depth sensors, laser depth sensor and meteorological instruments was installed next to the site to collect in situ measurements of snow, weather, and soil conditions. Preliminary tomographic processing of ground based SAR data of snowpack at X- and Ku- band has revealed the presence of multiple layers within

Structure and dating errors in the geologic time scale and periodicity in mass extinctions

Science.gov (United States)

Stothers, Richard B.

1989-01-01

Structure in the geologic time scale reflects a partly paleontological origin. As a result, ages of Cenozoic and Mesozoic stage boundaries exhibit a weak 28-Myr periodicity that is similar to the strong 26-Myr periodicity detected in mass extinctions of marine life by Raup and Sepkoski. Radiometric dating errors in the geologic time scale, to which the mass extinctions are stratigraphically tied, do not necessarily lessen the likelihood of a significant periodicity in mass extinctions, but do spread the acceptable values of the period over the range 25-27 Myr for the Harland et al. time scale or 25-30 Myr for the DNAG time scale. If the Odin time scale is adopted, acceptable periods fall between 24 and 33 Myr, but are not robust against dating errors. Some indirect evidence from independently-dated flood-basalt volcanic horizons tends to favor the Odin time scale.

Destination: Geology?

Science.gov (United States)

Price, Louise

2016-04-01

to the Canary Islands and Japan. The Great Britain Sasakawa Foundation, provided additional funding to support the recent visit to Japan, which enabled visits to Mount Fuji as well as investigating structural geology in Kobe and Tokyo. "The opportunity to visit Japan really broadened my understanding of geology and sharing that experience with fellow students helped me to reinforce my knowledge of the subject." Jack, geology student, Age 18.

Coastal barrier stratigraphy for Holocene high-resolution sea-level reconstruction.

Science.gov (United States)

Costas, Susana; Ferreira, Óscar; Plomaritis, Theocharis A; Leorri, Eduardo

2016-12-08

The uncertainties surrounding present and future sea-level rise have revived the debate around sea-level changes through the deglaciation and mid- to late Holocene, from which arises a need for high-quality reconstructions of regional sea level. Here, we explore the stratigraphy of a sandy barrier to identify the best sea-level indicators and provide a new sea-level reconstruction for the central Portuguese coast over the past 6.5 ka. The selected indicators represent morphological features extracted from coastal barrier stratigraphy, beach berm and dune-beach contact. These features were mapped from high-resolution ground penetrating radar images of the subsurface and transformed into sea-level indicators through comparison with modern analogs and a chronology based on optically stimulated luminescence ages. Our reconstructions document a continuous but slow sea-level rise after 6.5 ka with an accumulated change in elevation of about 2 m. In the context of SW Europe, our results show good agreement with previous studies, including the Tagus isostatic model, with minor discrepancies that demand further improvement of regional models. This work reinforces the potential of barrier indicators to accurately reconstruct high-resolution mid- to late Holocene sea-level changes through simple approaches.

Interannual changes in seafloor surficial geology at an artificial reef site on the inner continental shelf

Science.gov (United States)

Raineault, Nicole A.; Trembanis, Arthur C.; Miller, Douglas C.; Capone, Vince

2013-04-01

The influence of reef structures on seafloor surface sediments has implications for marine spatial planning and coastal development, including use of the coastal zone for offshore wind energy. We present results of interannual changes in seafloor surficial geology at the Redbird artificial reef site, located on the continental shelf offshore of Delaware Bay. The Redbird reef is composed of NYC subway cars, barges, tugboats, and other sunken objects. Since objects were added sporadically between 1996 and 2009, the survey area acts as a natural laboratory to study the evolution of the surrounding seafloor at a structural reef habitat through time. Annual side-scan surveys from 2008 through 2011, and one bathymetric survey in 2010 provide information about surface geology and morphology. Local wave and current data for this time period were analyzed to determine the main morphological agents. Automated backscatter segmentation show that three bottom types dominate and that these large-scale (>10 m) surface sediment patterns persist from year to year. Grab samples reveal that the bottom types are silty sand with clay and sandy gravel. Clear sediment and biological patterns emerged revealing the influence of the objects on the seafloor. Comet-shaped moats of sandy gravel surround single objects and grow to form large-scale coalesced patches around groups of objects. Alignment of sediment patches suggests the periodic hydrodynamic influence of seasonal storms. The abundance and diversity of organisms increases with decreasing clay/silt content. Evidence of scour includes the removal of fine sediments, the formation of moats 1-30 m in diameter and 0.5-1 m deep around the reef objects, and the >1 m settling of objects into the seafloor. Data suggest subway cars reached equilibrium with the environment in 6-7 years, but that larger objects or clusters of objects take a longer time to equilibrate and have farther-reaching effects. Knowledge of local wave and current climate

The results of borehole acoustic imaging from a granite in the Jihlava District, Czech Republic: implications for structural geological research

Czech Academy of Sciences Publication Activity Database

Nováková, Lucie; Novák, P.; Brož, Milan; Sosna, K.; Pitrák, K.; Kasíková, J.; Rukavičková, L.; Maňák, L.

2012-01-01

Roč. 4, č. 4 (2012), s. 92-101 ISSN 1916-9779 R&D Projects: GA MPO(CZ) FR-TI1/367 Institutional research plan: CEZ:AV0Z30460519 Keywords : acoustic borehole imaging * structural geology * paleostress analysis Subject RIV: DC - Siesmology, Volcanology, Earth Structure

Some new understanding on the characteristics of geological structure and uranium metallogenetic prospect on both sides of the Shandianhe down-faulted zone

International Nuclear Information System (INIS)

Zhang Xuequan

1992-01-01

On the basis of the systematic work in the field and at the laboratory, the metallogenetic prognosis map (1:100000) of geological structures and uranium metallogenetic prospect on both sides of the Shandianhe down-faulted zone is compiled. According to this, the regional setting of metallogenesis is emphatically expounded and some new understanding is presented. After the detailed study on the characteristics of geological structures on both sides of the Shangdianhe down-faulted zone, the metallogenetic prospective area are selected and the further prospecting targets in the area are suggested

Towards the Redefinition of the Global Stratigraphy of Mercury: The Case of Intermediate Plains

Science.gov (United States)

Galluzzi, V.; Rothery, D. A.; Massironi, M.; Ferranti, L.; Mercury Mapping Team

2018-05-01

Observations based on an average mapping scale of 1:400k provide context for the redefinition of the global stratigraphy of Mercury. Results show that the Intermediate Plains unit should be re-introduced as an official mappable terrain.

Modeling of the Sedimentary Interbedded Basalt Stratigraphy for the Idaho National Laboratory Probabilistic Seismic Hazard Analysis

Energy Technology Data Exchange (ETDEWEB)

Suzette Payne

2006-04-01

This report summarizes how the effects of the sedimentary interbedded basalt stratigraphy were modeled in the probabilistic seismic hazard analysis (PSHA) of the Idaho National Laboratory (INL). Drill holes indicate the bedrock beneath INL facilities is composed of about 1.1 km of alternating layers of basalt rock and loosely consolidated sediments. Alternating layers of hard rock and “soft” loose sediments tend to attenuate seismic energy greater than uniform rock due to scattering and damping. The INL PSHA incorporated the effects of the sedimentary interbedded basalt stratigraphy by developing site-specific shear (S) wave velocity profiles. The profiles were used in the PSHA to model the near-surface site response by developing site-specific stochastic attenuation relationships.

Modeling of the Sedimentary Interbedded Basalt Stratigraphy for the Idaho National Laboratory Probabilistic Seismic Hazard Analysis

Energy Technology Data Exchange (ETDEWEB)

Suzette Payne

2007-08-01

This report summarizes how the effects of the sedimentary interbedded basalt stratigraphy were modeled in the probabilistic seismic hazard analysis (PSHA) of the Idaho National Laboratory (INL). Drill holes indicate the bedrock beneath INL facilities is composed of about 1.1 km of alternating layers of basalt rock and loosely consolidated sediments. Alternating layers of hard rock and “soft” loose sediments tend to attenuate seismic energy greater than uniform rock due to scattering and damping. The INL PSHA incorporated the effects of the sedimentary interbedded basalt stratigraphy by developing site-specific shear (S) wave velocity profiles. The profiles were used in the PSHA to model the near-surface site response by developing site-specific stochastic attenuation relationships.

The geologic evolution of the planet Mars

International Nuclear Information System (INIS)

Masson, P.

1982-01-01

A brief summary of our knowledge on the Martian geology is presented here based on the results published by the members of Mariner 9 and Viking Orbiter Imaging Teams, the NASA Planetary Geology Principal Investigators and the scientists involved in the Mars Data Analysis Program. A special emphasis is given to the geologic evolution (volcanism and tectonism) related to our knowledge on the internal structure of the planet

Google Earth Mapping Exercises for Structural Geology Students--A Promising Intervention for Improving Penetrative Visualization Ability

Science.gov (United States)

Giorgis, Scott

2015-01-01

Three-dimensional thinking skills are extremely useful for geoscientists, and at the undergraduate level, these skills are often emphasized in structural geology courses. Google Earth is a powerful tool for visualizing the three-dimensional nature of data collected on the surface of Earth. The results of a 5 y pre- and posttest study of the…

Carboniferous-Permian sedimentology and stratigraphy of the Nordfjorden High and Loppa Spur, Arctic Norway

DEFF Research Database (Denmark)

Ahlborn, Morten

Abstract (shortened) Facies analysis of Late Paleozoic warm-water carbonates, were conducted in order to investigate the depositional evolution, cyclicity, internal architecture and sequence stratigraphy of the upper Gipsdalen Group carbonate platform on the Nordfjorden High in central Spitsberge...

Geologic studies

International Nuclear Information System (INIS)

Wayland, T.E.; Rood, A.

1983-01-01

The modern Great Divide Basin is the end product of natural forces influenced by the Green River lake system, Laramide tectonism, and intermittent volcanic events. It ranks as one of the most complex structural and stratigtaphic features within the Tertiary basins of Wyoming. Portions of the Great Divide Basin and adjoining areas in Wyoming have been investigated by applying detailed and region exploration methods to known uranium deposits located within the Red Desert portions of the basin. Geologic field investigations conducted by Bendix Field Engineering Corporaton (Bendix) were restricted to reconnaissance observations made during infrequent visits to the project area by various Bendix personnel. Locations of the most comprehensive field activities are shown in Figure II-1. The principal source fo data for geologic studies of the Red Desert project area has been information and materials furnished by industry. Several hundred holes have been drilled by various groups to delineate the uranium deposits. Results from Bendix-drilled holes at selected locations within the project area are summarized in Table II-1. Additional details and gross subsurface characteristics are illustrated in cross sections; pertinent geologic features are illustrated in plan maps. Related details of continental sedimentation that pertain to the Wyoming Basins generally, and the project area specificially, are discussed in subsections of this Geologic Studies section

Modelling of radionuclide transport along the underground access structures of deep geological repositories

Energy Technology Data Exchange (ETDEWEB)

Poller, A. [National Cooperative for the Disposal of Radioactive Waste (NAGRA), Wettingen (Switzerland); Smith, P. [SAM Switzerland GmbH, Zuerich (Switzerland); Mayer, G.; Hayek, M. [AF-Consult Switzerland AG, Baden (Switzerland)

2014-08-15

The arrangement and sealing of the access routes to a deep geological repository for radioactive waste should ensure that any radionuclide release from the emplacement rooms during the post closure phase does not by-pass the geological barriers of the repository system to a significant extent. The base case of the present study, where realistic values for the hydraulic properties of the seals and the associated excavation damage zones were assumed, assesses to what extent this is actually the case for different layout variants (ramp and shaft access and shaft access only). Furthermore, as a test of robustness of system performance against uncertainties related to such seals and the associated excavation damage zones, the present study also considers a broad spectrum of calculation cases including the hypothetical possibility that the seals perform much more poorly than expected and to check whether, consequently, the repository tunnel system and the access structures may provide significant release pathways. The study considers a generic repository system for high-level waste (HLW repository) and for low- and intermediate-level waste (L/ILW repository), both with Opalinus Clay as the host rock. It also considers the alternative possibilities of a ramp or a shaft as the access route for material transport (waste packages, etc.) to the underground facilities. Additional shafts, e.g. for the transport of persons and for ventilation, are included in both cases. The overall modelling approach consists of three broad steps: (a) the network of tunnels and access structures is implemented in a flow model, which serves to calculate water flow rates along the tunnels and through the host rock; (b) all relevant transport paths are implemented in a radionuclide release and transport model, the water flow rates being obtained from the preceding flow model calculations; (c) individual effective dose rates arising from the radionuclides released from the considered repository

Use of high-resolution satellite images for detection of geological structures related to Central Andes geothermal field, Chile.

Science.gov (United States)

Benavides-Rivas, C. L.; Soto-Pinto, C. A.; Arellano-Baeza, A. A.

2014-12-01

Central valley and the border with Argentina in the center, and in the fault system Liquiñe-Ofqui in the South of the country. High resolution images from the LANDSAT 8 satellite have been used to delineate the geological structures related to the potential geothermal reservoirs located at the northern end of the Southern Volcanic Zone of Chile. It was done by applying the lineament extraction technique, using the ADALGEO software, developed by [Soto et al., 2013]. These structures have been compared with the distribution of main geological structures obtained in the field. It was found that the lineament density increases in the areas of the major heat flux indicating that the lineament analysis could be a power tool for the detection of faults and joint zones associated to the geothermal fields. A lineament is generally defined as a straight or slightly curved feature in the landscape visible satellite image as an aligned sequence of pixel intensity contrast compared to the background. The system features extracted from satellite images is not identical to the geological lineaments that are generally determined by ground surveys, however, generally reflects the structure of faults and fractures in the crust. A temporal sequence of eight Landsat multispectral images of Central Andes geothermal field, located in VI region de Chile, was used to study changes in the configuration of the lineaments during 2011. The presence of minerals with silicification, epidotization, and albitization, which are typical for geothrmal reservoirs, was also identified, using their spectral characteristics, and subsequently corroborated in the field. Both lineament analysis and spectral analysis gave similar location of the reservoir, which increases reliability of the results.

Facies Analysis and Sequence Stratigraphy of Missole Outcrops: N’Kapa Formation of the South-Eastern Edge of Douala Sub-Basin (Cameroon)

OpenAIRE

Kwetche , Paul; Ntamak-Nida , Marie Joseph; Nitcheu , Adrien Lamire Djomeni; Etame , Jacques; Owono , François Mvondo; Mbesse , Cecile Olive; Kissaaka , Joseph Bertrand Iboum; Ngon , Gilbert Ngon; Bourquin , Sylvie; Bilong , Paul

2018-01-01

International audience; Missole facies description and sequence stratigraphy analysis allow a new proposal of depositional environments of the Douala sub-basin eastern part. The sediments of Missole outcrops (N’kapa Formation) correspond to fluvial/tidal channel to shallow shelf deposits with in some place embayment deposits within a warm and semi-arid climate. Integrated sedimentologic, palynologic and mineralogical data document a comprehensive sequence stratigraphy of this part of the Doua...

Comparison of the SKI, SKB, and SKN geological and structural models of the Aespoe area

International Nuclear Information System (INIS)

Tiren, S.A.

1996-06-01

Three sets of geological and structural models produced by three different groups are compared. The same set of basic data has been available to each of the groups. The models, all of which are 2 by 2 km by 1 km deep - or smaller, are based entirely on surface-based investigations. The modelled area is centered on the island of Aespoe, where SKB has built the Hard Rock Laboratory (HRL) in plutonic bedrock at a depth of 500 m. SKB (Swedish Nuclear Fuel and Waste Management Co) has recorded the basic data during the period 1986 to 1991, before starting the underground work. One of the main tasks in the SKB characterization of the HRL rock mass was to predict which of the geological structures will have the greatest rock-mechanical and hydraulic significance. The National Board for Spent Nuclear Fuel (SKN) constructed alternative models in 1992 to verify the SKB model. However, the SKN models were subsequently modified and converted into a hydrogeological model. The Swedish Nuclear Inspectorate (SKI) chose Aespoe as a hypothetical site for storage of nuclear waste in their SITE 94 project. The objective of the project is to assist SKI in their future review of SKB's application for a license to dispose of spent nuclear fuel underground. The agreement of the three models is found to be best where the density of information is greatest. The main difference between the two geological models is related to the inferred effects of block faulting on the rock type distribution. The correlation of moderately to gently inclined zones between the models is relatively poor at depth

Comparison of the SKI, SKB, and SKN geological and structural models of the Aespoe area

Energy Technology Data Exchange (ETDEWEB)

Tiren, S.A. [Geosigma AB, Uppsala (Sweden)

1996-06-01

Three sets of geological and structural models produced by three different groups are compared. The same set of basic data has been available to each of the groups. The models, all of which are 2 by 2 km by 1 km deep - or smaller, are based entirely on surface-based investigations. The modelled area is centered on the island of Aespoe, where SKB has built the Hard Rock Laboratory (HRL) in plutonic bedrock at a depth of 500 m. SKB (Swedish Nuclear Fuel and Waste Management Co) has recorded the basic data during the period 1986 to 1991, before starting the underground work. One of the main tasks in the SKB characterization of the HRL rock mass was to predict which of the geological structures will have the greatest rock-mechanical and hydraulic significance. The National Board for Spent Nuclear Fuel (SKN) constructed alternative models in 1992 to verify the SKB model. However, the SKN models were subsequently modified and converted into a hydrogeological model. The Swedish Nuclear Inspectorate (SKI) chose Aespoe as a hypothetical site for storage of nuclear waste in their SITE 94 project. The objective of the project is to assist SKI in their future review of SKB`s application for a license to dispose of spent nuclear fuel underground. The agreement of the three models is found to be best where the density of information is greatest. The main difference between the two geological models is related to the inferred effects of block faulting on the rock type distribution. The correlation of moderately to gently inclined zones between the models is relatively poor at depth. 46 refs, 30 figs, 18 tabs.

Economic geology of the Bingham mining district, Utah, with a section on areal geology, and an introduction on general geology

Science.gov (United States)

Boutwell, J.M.; Keith, Arthur; Emmons, S.F.

1905-01-01

The field work of which this report represents the final results was first undertaken in the summer of the year 1900. This district had long been selected by the writer as worthy of special economic investigation, as well on account of the importance of its products as because of its geological structure and the peculiar relations of its ore deposits. It was not, however, until the summer mentioned above that the means at the disposal of the Survey, both pecuniary and scientific, justified its undertaking. As originally planned, the areal or surface geology was to have been worked out by Mr. Keith, who had already spent many years in unraveling the complicated geological structure of the Appalachian province, while Mr. Boutwell, who had more recently become attached to the Survey, was to have charge of the underground geology, or a study of the ore deposits, under the immediate supervision of the writer. When the time came for actually taking the field, it was found that the pressure of other work would not permit Mr. Keith to carry out fully the part allotted to him, and in consequence a part of his field work has fallen to Mr. Boutwell. Field work was commenced by the writer and Mr. Boutwell early in July, 1900. Mr. Keith joined the party on August 10, but was obliged to leave for other duties early in September. Mr. Boutwell carried on his field work continuously from July until December, taking up underground work after the snowfall had rendered work on the surface geology impracticable. The geological structure had proved to be unexpectedly intricate and complicated, so that, on the opening of the field season of 1901, it was found necessary to make further study in the light of results already worked out, and Mr. Boutwell spent some weeks in the district in the early summer of 1901. His field work that year, partly in California and partly in Arizona, as assistant to Mr. Waldemar Lindgren, lasted through the summer and winter and well into the spring of 1902

Geological Structure and Gold Mineralization of Carbonaceous Deposits of the Tyotechnaya Mountain (South Urals)

OpenAIRE

A. V. Snachev; E. P. Shchulkin

2018-01-01

This paper considers the geological structure of the northern part of the East-Urals Trough. Particular attention is paid to the Kosobrodskaya Formation, where the carbonaceous deposits are most abundant. It was found that the gold in the black shales of the Tyotechnaya Mountain is associated with the intensively dislocated, silicified and sulfidised rocks struck with the diorite porphyry of the Birgildin-Tomino Complex. Channel sampling on the number of wells showed the gold grades up to 1.5...

Geology and structure of the Malpaso caldera and El Ocote ignimbrite, Aguascalientes, Mexico

International Nuclear Information System (INIS)

Nieto-Obregon, Jorge; Aguirre-DIaz, Gerardo

2008-01-01

A new caldera, named Malpaso, is reported west of the city of Aguascalientes, Mexico. The Malpaso caldera is a volcano-tectonic depression, highly fractured and faulted, and was filled by voluminous pyroclastic products related to the caldera collapse. Due to these characteristics it as a graben caldera. It is truncated by younger normal faults of the Calvillo and Aguascalientes grabens. In this work we present a summary of the geologic and structural observations on this caldera, as well as a description of the main caldera product, the high-grade El Ocote ignimbrite.

Geology and structure of the Malpaso caldera and El Ocote ignimbrite, Aguascalientes, Mexico

Energy Technology Data Exchange (ETDEWEB)

Nieto-Obregon, Jorge [Facultad de IngenierIa, UNAM, Coyoacan, 04510, Mexico D.F. (Mexico); Aguirre-DIaz, Gerardo [Centro de Geociencias, UNAM, Campus Juriquilla, 76220, Queretaro, Qro. (Mexico)], E-mail: nieto@servidor.unam.mx, E-mail: ger@geociencias.unam.mx

2008-10-01

A new caldera, named Malpaso, is reported west of the city of Aguascalientes, Mexico. The Malpaso caldera is a volcano-tectonic depression, highly fractured and faulted, and was filled by voluminous pyroclastic products related to the caldera collapse. Due to these characteristics it as a graben caldera. It is truncated by younger normal faults of the Calvillo and Aguascalientes grabens. In this work we present a summary of the geologic and structural observations on this caldera, as well as a description of the main caldera product, the high-grade El Ocote ignimbrite.

Geological techniques used in the siting of South Africa's nuclear facilities

International Nuclear Information System (INIS)

Andersen, N.J.B.

1990-01-01

Nuclear site selection studies begin with an initial screening phase in order to pick regions which could be potentially suitable. When assessing a potential nuclear site from a structural geological point of view, the most important factors are the presence of 'capable faults', the seismicity of the area, and the existence of good foundation rock. A geological evaluation of a potential site involves a literature survey for all existing geological data on the site, geophysical investigations, structural domain analysis and geological mapping

Genetic stratigraphy and palaeoenvironmental controls on coal distribution in the Witbank Basin Coalfield

Energy Technology Data Exchange (ETDEWEB)

LeBlanc, G

1981-01-01

Subsurface data from over 1200 boreholes in the Witbank basin coalfield provided information for determining the coalfield stratigraphy and the palaeoenvironmental controls on coal distribution. The inadequacies of existing coalfield lithostratigraphy are obviated by the erection of a genetic coalfield stratigraphy. A total of ten areally extensive defined marker surfaces resolve the sedimentary succession into nine defined fundamental genetically realted stratal increments, termed Genetic increments of strata(GIS's); these are grouped into four defined Genetic Sequences of Strata (GSS's), termed from the base upwards, the Witbank, Coalville, Middleburg and Van Dyks Drift GSS's which are respectively grouped to comprise a single genetic Generation of strata, termed the Ogies Generation. Coalfield genetic stratigraphy is summarized in graphic mode in a composite stratigraphic column. It is concluded from this study that with the northward retreat of the late-Palaeozoic Gondwana ice sheet a series of glacial valleys, partially filled with diamicite, dominated the landscape along the northern edge of the Karoo basin. Consequent outwash sediments constitute the Witbank GSS and accumulated as paraglacial, glaciofluvial and glaciolacustrine deltaic deposits, in the primeval Dwyka-Ecca Sea. Upon abandonment, shallow-rooted Tundra vegetation proliferated, and multi-channel outwash streams were stabilised, confined and enveloped by areally extensive accumulation of peat, that reached up to 24 m in thickness, and which constituted precursors to the 1 and 2 Seam coals which attain a combined thickness of up to 12,5 m. Variations i coal petrographic character and ash content are attributed to: overbank splaying within the proximity of recognisable syndepositional (in-seam) vegetation-stabilised channels; and to the progressively increased introduction of suspended sediment as a consequence of transgressive inundation prior to burial.

Geology and geohydrology of the Palo Duro Basin, Texas Panhandle. Report on the progress of nuclear waste isolation feasibility studies, 1979

International Nuclear Information System (INIS)

Gustavson, T.C.; Presley, M.W.; Handford, C.R.; Finley, R.J.; Dutton, S.P.; Baumgardner, R.W. Jr.; McGillis, K.A.; Simpkins, W.W.

1980-01-01

Since early 1977, the Bureau of Economic Geology has been evaluating several salt-bearing basins within the State of Texas as part of the national nuclear repository program. The Bureau, a research unit of The University of Texas at Austin and the State of Texas, is carrying out a long-term program to gather and interpret all geologic and hydrologic information necessary for description, delineation, and evaluation of salt-bearing strata in the Palo Duro and Dalhart Basins of the Texas Panhandle. The program in FY 79 has been subdivided into four broad research tasks, which are addressed by a basin analysis group, a surface studies group, a geohydrology group, and a host-rock analysis group. The basin analysis group has delineated the structural and stratigraphic framework of the basins, initiated natural resource assessment, and integrated data from 8000 ft (2400 m) of core material into salt-stratigraphy models. Salt depth and thickness have been delineated for seven salt-bearing stratigraphic units. Concurrently, the surface studies group has collected ground and remotely sensed data to describe surficial processes, including salt solution, slope retreat/erosion mechanisms, geomorphic evolution, and fracture system development. The basin geohydrology group has begun evaluating both shallow and deep fluid circulation within the basins. The newly formed host-rock analysis group has initiated study of cores from two drilling sites for analysis of salt and the various lithologies overlying and interbedded with salt units. This paper, a summary report of progress in FY 79, presents principal conclusions and reviews methods used and types of data and maps generated

Summary and evaluation of existing geological and geophysical data near prospective surface facilities in Midway Valley, Yucca Mountain Project, Nye County, Nevada

International Nuclear Information System (INIS)

Gibson, J.D.; Swan, F.H.; Wesling, J.R.; Bullard, T.F.; Perman, R.C.; Angell, M.M.; DiSilvestro, L.A.

1992-01-01

Midway Valley, located at the eastern base of the Yucca Mountain in southwestern Nevada, is the preferred location of the surface facilities for the potential high-level nuclear waste repository at Yucca Mountain. One goal in siting these surface facilities is to avoid faults that could produce relative displacements in excess of 5 cm in the foundations of the waste-handling buildings. This study reviews existing geologic and geophysical data that can be used to assess the potential for surface fault rupture within Midway Valley. Dominant tectonic features in Midway Valley are north-trending, westward-dipping normal faults along the margins of the valley: the Bow Ridge fault to the west and the Paintbrush Canyon fault to the east. Published estimates of average Quaternary slip rates for these faults are very low but the age of most recent displacement and the amount of displacement per event are largely unknown. Surface mapping and interpretive cross sections, based on limited drillhole and geophysical data, suggest that additional normal faults, including the postulated Midway Valley fault, may exist beneath the Quaternary/Tertiary fill within the valley. Existing data, however, are inadequate to determine the location, recency, and geometry of this faulting. To confidently assess the potential for significant Quaternary faulting in Midway Valley, additional data are needed that define the stratigraphy and structure of the strata beneath the valley, characterize the Quaternary soils and surfaces, and establish the age of faulting. The use of new and improved geophysical techniques, combined with a drilling program, offers the greatest potential for resolving subsurface structure in the valley. Mapping of surficial geologic units and logging of soil pits and trenches within these units must be completed, using accepted state-of-the-art practices supported by multiple quantitative numerical and relative age-dating techniques

Sudbury project (University of Muenster-Ontario Geological Survey): Summary of results - an updated impact model

Science.gov (United States)

Avermann, M.; Bischoff, L.; Brockmeyer, P.; Buhl, D.; Deutsch, A.; Dressler, B. O.; Lakomy, R.; Mueller-Mohr, V.; Stoeffler, D.

1992-01-01

In 1984 the Ontario Geological Survey initiated a research project on the Sudbury structure (SS) in cooperation with the University of Muenster. The project included field mapping (1984-1989) and petrographic, chemical, and isotope analyses of the major stratigraphic units of the SS. Four diploma theses and four doctoral theses were performed during the project (1984-1992). Specific results of the various investigations are reported. Selected areas of the SS were mapped and sampled: Footwall rocks; Footwall breccia and parts of the sublayer and lower section of the Sudbury Igneous Complex (SIC); Onaping Formation and the upper section of the SIC; and Sudbury breccia and adjacent Footwall rocks along extended profiles up to 55 km from the SIC. All these stratigraphic units of the SS were studied in substantial detail by previous workers. The most important characteristic of the previous research is that it was based either on a volcanic model or on a mixed volcanic-impact model for the origin of the SS. The present project was clearly directed toward a test of the impact origin of the SS without invoking an endogenic component. In general, our results confirm the most widely accepted stratigraphic division of the SS. However, our interpretation of some of the major stratigraphic units is different from most views expressed. The stratigraphy of the SS and its new interpretation is given as a basis for discussion.

Early Palaeogene planktic foraminiferal and carbon isotope stratigraphy, ODP hole 762C, Exmouth plateau, Northwest Australian margin

International Nuclear Information System (INIS)

Hancock, H.J.L.; Dickens, G.R.; Henderson, R.R.; Chaproniere, G.C.

1999-01-01

recalibrated magnetostratigraphy, the planktic foraminiferal record at Site 762 provides an integrated and detailed early Palaeogene stratigraphy for the North West Shelf. Importantly a complete, expanded and shallow buried early Palaeogene sediment record exists on the Exmouth Plateau. The location is ideal for future scientific drilling to understand profound palaeoceanographic variations in the Palaeogene. Copyright (1999) Geological Society of Australia

Combined constraints on the structure and physical properties of the East Antarctic lithosphere from geology and geophysics.

Science.gov (United States)

Reading, A. M.; Staal, T.; Halpin, J.; Whittaker, J. M.; Morse, P. E.

2017-12-01

The lithosphere of East Antarctica is one of the least explored regions of the planet, yet it is gaining in importance in global scientific research. Continental heat flux density and 3D glacial isostatic adjustment studies, for example, rely on a good knowledge of the deep structure in constraining model inputs.In this contribution, we use a multidisciplinary approach to constrain lithospheric domains. To seismic tomography models, we add constraints from magnetic studies and also new geological constraints. Geological knowledge exists around the periphery of East Antarctica and is reinforced in the knowledge of plate tectonic reconstructions. The subglacial geology of the Antarctic hinterland is largely unknown but the plate reconstructions allow the well-posed extrapolation of major terranes into the interior of the continent, guided by the seismic tomography and magnetic images. We find that the northern boundary of the lithospheric domain centred on the Gamburtsev Subglacial Mountains has a possible trend that runs south of the Lambert Glacier region, turning coastward through Wilkes Land. Other periphery-to-interior connections are less well constrained and the possibility of lithospheric domains that are entirely sub-glacial is high. We develop this framework to include a probabilistic method of handling alternate models and quantifiable uncertainties. We also show first results in using a Bayesian approach to predicting lithospheric boundaries from multivariate data.Within the newly constrained domains, we constrain heat flux (density) as the sum of basal heat flux and upper crustal heat flux. The basal heat flux is constrained by geophysical methods while the upper crustal heat flux is constrained by geology or predicted geology. In addition to heat flux constraints, we also consider the variations in friction experienced by moving ice sheets due to varying geology.

Structural mapping from MSS-LANDSAT imagery: A proposed methodology for international geological correlation studies

Science.gov (United States)

Dejesusparada, N. (Principal Investigator); Crepani, E.; Martini, P. R.

1980-01-01

A methodology is proposed for international geological correlation studies based on LANDSAT-MSS imagery, Bullard's model of continental fit and compatible structural trends between Northeast Brazil and the West African counterpart. Six extensive lineaments in the Brazilian study area are mapped and discussed according to their regional behavior and in relation to the adjacent continental margin. Among the first conclusions, correlations were found between the Sobral Pedro II Lineament and the megafaults that surround the West African craton; and the Pernambuco Lineament with the Ngaurandere Linemanet in Cameroon. Ongoing research to complete the methodological stages includes the mapping of the West African structural framework, reconstruction of the pre-drift puzzle, and an analysis of the counterpart correlations.

Three dimensional visualization in support of Yucca Mountain Site characterization activities

International Nuclear Information System (INIS)

Brickey, D.W.

1992-01-01

An understanding of the geologic and hydrologic environment for the proposed high-level nuclear waste repository at Yucca Mountain, NV is a critical component of site characterization activities. Conventional methods allow visualization of geologic data in only two or two and a half dimensions. Recent advances in computer workstation hardware and software now make it possible to create interactive three dimensional visualizations. Visualization software has been used to create preliminary two-, two-and-a-half-, and three-dimensional visualizations of Yucca Mountain structure and stratigraphy. The three dimensional models can also display lithologically dependent or independent parametric data. Yucca Mountain site characterization studies that will be supported by this capability include structural, lithologic, and hydrologic modeling, and repository design

Stratigraphy and dissolution of the Rustler Formation

International Nuclear Information System (INIS)

Bachman, G.O.

1985-01-01

The Rustler Formation is the uppermost evaporite-bearing unit in the Permian Ochoan series in southeastern New Mexico. It rests on the Salado Formation which includes the salt beds where the mined facility for the Waste Isolation Pilot Plant (WIPP) is being constructed. An understanding of the physical stratigraphy of the Rustler Formation is pertinent to studies of the WIPP site because some portions of the Rustler are water-bearing and may provide paths for circulating waters to come into contact with, and dissolve, evaporites within the Ochoan sequence. Knowledge of the processes, magnitude, and history of evaporite dissolution in the vicinity of the WIPP site is important to an evaluation of the integrity of the site. 2 refs., 2 figs

Integrated stratigraphy and astronomical tuning of Smirra cores, lower Eocene, Umbria-Marche basin, Italy.

Science.gov (United States)

Lauretano, Vittoria; Turtù, Antonio; Hilgen, Frits; Galeotti, Simone; Catanzariti, Rita; Reichart, Gert Jan; Lourens, Lucas J.

2016-04-01

The early Eocene represents an ideal case study to analyse the impact of increase global warming on the ocean-atmosphere system. During this time interval, the Earth's surface experienced a long-term warming trend that culminated in a period of sustained high temperatures called the Early Eocene Climatic Optimum (EECO). These perturbations of the ocean-atmosphere system involved the global carbon cycle and global temperatures and have been linked to orbital forcing. Unravelling this complex climatic system strictly depends on the availability of high-quality suitable geological records and accurate age models. However, discrepancies between the astrochronological and radioisotopic dating techniques complicate the development of a robust time scale for the early Eocene (49-54 Ma). Here we present the first magneto-, bio-, chemo- and cyclostratigraphic results of the drilling of the land-based Smirra section, in the Umbria Marche Basin. The sediments recovered at Smirra provide a remarkably well-preserved and undisturbed succession of the early Palaeogene pelagic stratigraphy. Bulk stable carbon isotope and X-Ray Fluorescence (XRF) scanning records are employed in the construction of an astronomically tuned age model for the time interval between ~49 and ~54 Ma based on the tuning to long-eccentricity. These results are then compared to the astronomical tuning of the benthic carbon isotope record of ODP Site 1263 to evaluate the different age model options and improve the time scale of the early Eocene by assessing the precise number of eccentricity-related cycles comprised in this critical interval.

Geostatistical simulation of geological architecture and uncertainty propagation in groundwater modeling

DEFF Research Database (Denmark)

He, Xiulan

parameters and model structures, which are the primary focuses of this PhD research. Parameter uncertainty was analyzed using an optimization tool (PEST: Parameter ESTimation) in combination with a random sampling method (LHS: Latin Hypercube Sampling). Model structure, namely geological architecture...... be compensated by model parameters, e.g. when hydraulic heads are considered. However, geological structure is the primary source of uncertainty with respect to simulations of groundwater age and capture zone. Operational MPS based software has been on stage for just around ten years; yet, issues regarding...... geological structures of these three sites provided appropriate conditions for testing the methods. Our study documented that MPS is an efficient approach for simulating geological heterogeneity, especially for non-stationary system. The high resolution of geophysical data such as SkyTEM is valuable both...

Cenozoic geology of the Yolomécatl-Tlaxiaco area, Northwestern Oaxaca, Southeastern Mexico: Stratigraphy, structure and regional significance

Science.gov (United States)

Ferrusquía-Villafranca, Ismael; Ruiz-González, José E.; Torres-Hernández, José Ramón; Anderson, Thomas H.; Urrutia-Fucugauchi, Jaime; Martínez-Hernández, Enrique; García-Villegas, Felipe

2016-12-01

The Yolomécatl-Tlaxiaco Area, lies in the rugged Sierra Madre del Sur (SMS) of northwestern Oaxaca (YOTLA), southeastern Mexico. Within the area Cenozoic units unconformably overlie metamorphic, clastic and carbonate rock units of Late Paleozoic to Cretaceous ages as well as the Mixteco/Oaxaca Terrane boundary. The Cenozoic sequence, emphasized herein, includes from botton to top: (1) basal, calcilithitic Early Tertiary Tamazulapam Conglomerate, (2) andesitic lava flows of Nduayaco "Group," (3-4) Epiclastic/pyroclastic strata composing Yolomécatl Formation (∼40.3 ± 1.0 Ma), and Tayata Pyroepiclastics (5) Early Oligocene (∼32.9 Ma), felsic, pyroclastic Nundichi "Group," (6) Late Oligocene (∼27.7 ± 0.7 Ma) andesitic lava flows of Nicananduta "Group" containing intercalations of unit (7) ?Chilapa Formation (largely lacustrine). Quaternary deposits unconformably overlie the sequence. The structural record includes NNW-SSE folds in the Mesozoic units, and one in Tayata Pyroepiclastics, as well as numerous fractures/faults of diverse types, whose pattern seems to roughly define four geographic/structural domains, NW, SW, S, and E. The Tertiary sequence records four magmatic and six deformational events: Pre-Late Eocene Extension accommodated by the Tamazulapam fault, along which magma of the Nduayaco "Group" moved upward. The next episode is the earliest Late Eocene extension recorded by the Yucuxaco-Santa Cruz Tayata fault was followed by accumulation of Yolomécatl Formation, Tayata Pyroepiclastics, and synsedimentary emplacement of tuff sheets at ∼40.3 ± 1.0 Ma. After this date, left lateral transpression emplaced a Teposcolula Limestone block over Nduayaco "Group" and ?Yolomécatl Formation, whereas the Tayata Pyroepiclastics was folded into an open anticline. Movement along the Yucuxaco-Santa Cruz Tayayata fault suite influenced accumulation of the Nundichi "Group" strata ca. ∼32.9 Ma. Subsequent ENE-WSW extension affected the Nundichi "Group," partly

Astronomical calibration of the geological timescale: closing the middle Eocene gap

Science.gov (United States)

Westerhold, T.; Röhl, U.; Frederichs, T.; Bohaty, S. M.; Zachos, J. C.

2015-09-01

To explore cause and consequences of past climate change, very accurate age models such as those provided by the astronomical timescale (ATS) are needed. Beyond 40 million years the accuracy of the ATS critically depends on the correctness of orbital models and radioisotopic dating techniques. Discrepancies in the age dating of sedimentary successions and the lack of suitable records spanning the middle Eocene have prevented development of a continuous astronomically calibrated geological timescale for the entire Cenozoic Era. We now solve this problem by constructing an independent astrochronological stratigraphy based on Earth's stable 405 kyr eccentricity cycle between 41 and 48 million years ago (Ma) with new data from deep-sea sedimentary sequences in the South Atlantic Ocean. This new link completes the Paleogene astronomical timescale and confirms the intercalibration of radioisotopic and astronomical dating methods back through the Paleocene-Eocene Thermal Maximum (PETM, 55.930 Ma) and the Cretaceous-Paleogene boundary (66.022 Ma). Coupling of the Paleogene 405 kyr cyclostratigraphic frameworks across the middle Eocene further paves the way for extending the ATS into the Mesozoic.

Review of the Upper Jurassic-Lower Cretaceous stratigraphy in Western Cameros basin, Northern Spain

DEFF Research Database (Denmark)

Vidal, Maria del Pilar Clemente

2010-01-01

The Upper Jurassic-Lower Cretaceous stratigraphy of the Cameros basin has been reviewed. In Western Cameros the stratigraphic sections are condensed but they have a parallel development with the basin depocentre and the same groups have been identified. The Tera Group consists of two formations: ...

Engineering Geology | Alaska Division of Geological & Geophysical Surveys

Science.gov (United States)

Alaska's Mineral Industry Reports AKGeology.info Rare Earth Elements WebGeochem Engineering Geology Alaska content Engineering Geology Additional information Engineering Geology Posters and Presentations Alaska Alaska MAPTEACH Tsunami Inundation Mapping Engineering Geology Staff Projects The Engineering Geology

GeoSciML version 3: A GML application for geologic information

Science.gov (United States)

International Union of Geological Sciences., I. C.; Richard, S. M.

2011-12-01

After 2 years of testing and development, XML schema for GeoSciML version 3 are now ready for application deployment. GeoSciML draws from many geoscience data modelling efforts to establish a common suite of feature types to represent information associated with geologic maps (materials, structures, and geologic units) and observations including structure data, samples, and chemical analyses. After extensive testing and use case analysis, in December 2008 the CGI Interoperability Working Group (IWG) released GeoSciML 2.0 as an application schema for basic geological information. GeoSciML 2.0 is in use to deliver geologic data by the OneGeology Europe portal, the Geological Survey of Canada Groundwater Information Network (wet GIN), and the Auscope Mineral Resources portal. GeoSciML to version 3.0 is updated to OGC Geography Markup Language v3.2, re-engineered patterns for association of element values with controlled vocabulary concepts, incorporation of ISO19156 Observation and Measurement constructs for representing numeric and categorical values and for representing analytical data, incorporation of EarthResourceML to represent mineral occurrences and mines, incorporation of the GeoTime model to represent GSSP and stratigraphic time scale, and refactoring of the GeoSciML namespace to follow emerging ISO practices for decoupling of dependencies between standardized namespaces. These changes will make it easier for data providers to link to standard vocabulary and registry services. The depth and breadth of GeoSciML remains largely unchanged, covering the representation of geologic units, earth materials and geologic structures. ISO19156 elements and patterns are used to represent sampling features such as boreholes and rock samples, as well as geochemical and geochronologic measurements. Geologic structures include shear displacement structures (brittle faults and ductile shears), contacts, folds, foliations, lineations and structures with no preferred

Executive summary - Geologic assessment of coal in the Gulf of Mexico coastal plain, U.S.A.

Science.gov (United States)

Warwick, Peter D.; Warwick, Peter D.; Karlsen, Alexander K.; Merrill, Matthew D.; Valentine, Brett J.

2011-01-01

The National Coal Resource Assessment (NCRA) project of the U.S. Geological Survey (USGS) has assessed the quantity and quality of the nation's coal deposits that potentially could be mined during the next few decades. For eight years, geologic, geochemical, and resource information was collected and compiled for the five major coal-producing regions of the United States: the Appalachian Basin, Illinois Basin, Northern Rocky Mountains and Great Plains, Colorado Plateau, and the western part of the Gulf of Mexico Coastal Plain (Gulf Coast) region (Figure 1). In particular, the NCRA assessed resource estimates, compiled coal-quality information, and characterized environmentally sensitive trace elements, such as arsenic and mercury, that are mentioned in the 1990 Clean Air Act Amendments (U.S. Environmental Protection Agency, 1990). The results of the USGS coal assessment efforts may be found at: http://energy.cr.usgs.gov/coal/coal-assessments/index.html and a summary of the results from all assessment areas can be found in Ruppert et al. (2002) and Dennen (2009).Detailed assessments of the major coal-producing areas for the Gulf Coast region along with reviews of the stratigraphy, coal quality, resources, and coalbed methane potential of the Cretaceous, Paleocene, and Eocene coal deposits are presented in this report (Chapters 5-10).

Geologic structure in California: Three studies with ERTS-1 imagery

Science.gov (United States)

Lowman, P. D., Jr.

1974-01-01

Results are presented of three early applications of imagery from the NASA Earth Resources Technology Satellite to geologic studies in California. In the Coast Ranges near Monterey Bay, numerous linear drainage features possibly indicating unmapped fracture zones were mapped within one week after launch of the satellite. A similar study of the Sierra Nevada near Lake Tahoe revealed many drainage features probably formed along unmapped joint or faults in granitic rocks. The third study, in the Peninsular Ranges, confirmed existence of several major faults not shown on published maps. One of these, in the Sawtooth Range, crosses in Elsinore fault without lateral offset; associated Mid-Cretaceous structures have also been traced continuously across the fault without offset. It therefore appears that displacement along the Elsinore fault has been primarily of a dip-slip nature, at least in this area, despite evidence for lateral displacement elsewhere.

Depositional History and Sequence Stratigraphy of the Middle Ordovician Yeongheung Formation (Yeongweol Group), Taebaeksan Basin, mid-east Korea

Science.gov (United States)

Kwon, Yoo Jin; Kwon, Yi Kyun

2017-04-01

The Middle Ordovician Yeongheung Formation consists of numerous meter-scale, shallowing-upward cycles which were deposited on a shallow-marine carbonate platform. Many diagnostic sedimentary textures and structures such as supratidal laminite, tepee structure, and solution-collapsed breccia are observed, which enable to infer the dry climate and high salinity conditions during deposition of the formation. In order to understand its depositional history, this study focuses on vertical and spatial stacking patterns of the second- to third-order sequences through the detailed outcrop description and geologic mapping. A total 19 lithofacies have been recognized, which can be grouped into 5 facies associations (FAs): FA1 (Supratidal flat), FA2 (Supratidal or dolomitization of peritidal facies), FA3 (Intertidal flat), FA4 (Shallow subtidal to peritidal platform), FA5 (Shallow subtidal shoal). Global mega-sequence boundary (Sauk-Tippecanoe) occurs in solution-collapsed breccia zone in the lower part of the formation. Correlation of the shallowing-upward cycle stacking pattern across the study area defines 6 transgressive-regressive depositional sequences. Each depositional sequences comprises a package of vertical and spatial staking of shallow subtidal cycles in the lower part and peritidal cycles in the upper part of the formation. According to sequence stratigraphic interpretation, the reconstructed relative sea-level curve of the Yeongweol platform is very similar to that of the Taebaek platform. Based on the absence of siliciclastic sequence such as the Jigunsan Formation and the lithologic & stratigraphic differences, however, the Yeongweol and Taebaek groups might not belong to a single depositional system within the North China platform. The Yeongweol Group can be divided by the four subunits into their unique lithologic successions and geographic distributions. The Eastern subunit of the Yeongweol Group is composed dominantly of carbonate rocks with a high

Strabo: An App and Database for Structural Geology and Tectonics Data

Science.gov (United States)

Newman, J.; Williams, R. T.; Tikoff, B.; Walker, J. D.; Good, J.; Michels, Z. D.; Ash, J.

2016-12-01

Strabo is a data system designed to facilitate digital storage and sharing of structural geology and tectonics data. The data system allows researchers to store and share field and laboratory data as well as construct new multi-disciplinary data sets. Strabo is built on graph database technology, as opposed to a relational database, which provides the flexibility to define relationships between objects of any type. This framework allows observations to be linked in a complex and hierarchical manner that is not possible in traditional database topologies. Thus, the advantage of the Strabo data structure is the ability of graph databases to link objects in both numerous and complex ways, in a manner that more accurately reflects the realities of the collecting and organizing of geological data sets. The data system is accessible via a mobile interface (iOS and Android devices) that allows these data to be stored, visualized, and shared during primary collection in the field or the laboratory. The Strabo Data System is underlain by the concept of a "Spot," which we define as any observation that characterizes a specific area. This can be anything from a strike and dip measurement of bedding to cross-cutting relationships between faults in complex dissected terrains. Each of these spots can then contain other Spots and/or measurements (e.g., lithology, slickenlines, displacement magnitude.) Hence, the Spot concept is applicable to all relationships and observation sets. Strabo is therefore capable of quantifying and digitally storing large spatial variations and complex geometries of naturally deformed rocks within hierarchically related maps and images. These approaches provide an observational fidelity comparable to a traditional field book, but with the added benefits of digital data storage, processing, and ease of sharing. This approach allows Strabo to integrate seamlessly into the workflow of most geologists. Future efforts will focus on extending Strabo to

Abstracts

International Nuclear Information System (INIS)

2001-01-01

The minutes of the Latinamerican Geology Meeting and the 3. Uruguayan Meeting organized by the National Direction of Mining and Geology (DINAMIGE) and Uruguayan Geology Society (Uruguay) includes topics such as: paleontology, sedimentation, stratigraphy, fossils, paleoclimatology, geo tectonics, coal deposits, minerals res sources, tectonic evolution of the Andes Mountain Ranges, IGCP Project, Environmental geology, Hydrogeology, fuels, and geomorphology

Numerical Simulations of the Lunar Penetrating Radar and Investigations of the Geological Structures of the Lunar Regolith Layer at the Chang’E 3 Landing Site

Directory of Open Access Journals (Sweden)

Chunyu Ding

2017-01-01

Full Text Available In the process of lunar exploration, and specifically when studying lunar surface structure and thickness, the established lunar regolith model is usually a uniform and ideal structural model, which is not well-suited to describe the real structure of the lunar regolith layer. The present study aims to explain the geological structural information contained in the channel 2 LPR (lunar penetrating radar data. In this paper, the random medium theory and Apollo drilling core data are used to construct a modeling method based on discrete heterogeneous random media, and the simulation data are processed and collected by the electromagnetic numerical method FDTD (finite-difference time domain. When comparing the LPR data with the simulated data, the heterogeneous random medium model is more consistent with the actual distribution of the media in the lunar regolith layer. It is indicated that the interior structure of the lunar regolith layer at the landing site is not a pure lunar regolith medium but rather a regolith-rock mixture, with rocks of different sizes and shapes. Finally, several reasons are given to explain the formation of the geological structures of the lunar regolith layer at the Chang’E 3 landing site, as well as the possible geological stratification structure.

Software development for geologic information management system on open-pit production

Energy Technology Data Exchange (ETDEWEB)

Li, K.; Tian, A.; Ren, Z.; Pang, Y. [China University of Mining and Technomogy, Xuzhou (China). College of Mineral and Energy Resources

2001-09-01

A software, including geological data gathering and processing, deposit modelling, reserves calculating and mine map plotting, for geologic information management of open-pit production was developed. Based on the interactive technique, CAD, the object-oriented simulation, and the characteristics of geologic structures, all the geologic information databases and geologic mapping sub-systems have been established for open-pit production, planning and management. 6 refs., 1 fig.

Status Report on the Geology of the Oak Ridge Reservation

Energy Technology Data Exchange (ETDEWEB)

Hatcher, R.D., Jr.

1992-01-01

This report provides an introduction to the present state of knowledge of the geology of the Oak Ridge Reservation (ORR) and a cursory introduction to the hydrogeology. A detailed reported on hydrogeology is being produced in parallel to this one. An important element of this work is the construction of a modern detailed geologic map of the ORR containing subdivisions of all mappable rock units and displaying mesoscopic structural data. Understanding the geologic framework of the ORR is essential to many current and proposed activities related to land-use planning, waste management, environmental restoration, and waste remediation. This interim report is the result of cooperation between geologists in two Oak Ridge National Laboratory (ORNL) divisions, Environmental Sciences and Energy, and is a major part of one doctoral dissertation in the Department of Geological Sciences at The University of Tennessee--Knoxville. Major long-term goals of geologic investigations in the ORR are to determine what interrelationships exist between fractures systems in individual rock or tectonic units and the fluid flow regimes, to understand how regional and local geology can be used to help predict groundwater movement, and to formulate a structural-hydrologic model that for the first time would enable prediction of the movement of groundwater and other subsurface fluids in the ORR. Understanding the stratigraphic and structural framework and how it controls fluid flow at depth should be the first step in developing a model for groundwater movement. Development of a state-of-the-art geologic and geophysical framework for the ORR is therefore essential for formulating an integrated structural-hydrologic model. This report is also intended to convey the present state of knowledge of the geologic and geohydrologic framework of the ORR and vicinity and to present some of the data that establish the need for additional geologic mapping and geohydrologic studies. An additional intended

Structural geology of the Columbia Plateau and environs as related to the waste isolation safety assessment program

International Nuclear Information System (INIS)

Coombs, H.A.

1979-01-01

This report provides information on the structural geology of the Columbia Plateau in regard to selecting a site for radioactive waste disposal. This report describes the folding and faulting that has taken place during the past several million years, thus providing background for the general stress conditions of the area and giving clues to the mechanism of deformation

A state geological survey commitment to environmental geology - the Texas Bureau of Economic Geology

International Nuclear Information System (INIS)

Wermund, E.G.

1990-01-01

In several Texas environmental laws, the Bureau of Economic Geology is designated as a planning participant and review agency in the process of fulfilling environmental laws. Two examples are legislation on reclamation of surface mines and regulation of processing low level radioactive wastes. Also, the Bureau is the principal geological reviewer of all Environmental Assessments and Environmental Impact Statements which the Office of the Governor circulates for state review on all major developmental activities in Texas. The BEG continues its strong interest in environmental geology. In February 1988, it recommitted its Land Resources Laboratory, initiated in 1974, toward fulfilling needs of state, county, and city governments for consultation and research on environmental geologic problems. An editorial from another state geological survey would resemble the about description of texas work in environmental geology. State geological surveys have led federal agencies into many developments of environmental geology, complemented federal efforts in their evolution, and continued a strong commitment to the maintenance of a quality environment through innovative geologic studies

The First Global Geological Map of Mercury

Science.gov (United States)

Prockter, L. M.; Head, J. W., III; Byrne, P. K.; Denevi, B. W.; Kinczyk, M. J.; Fassett, C.; Whitten, J. L.; Thomas, R.; Ernst, C. M.

2015-12-01

Geological maps are tools with which to understand the distribution and age relationships of surface geological units and structural features on planetary surfaces. Regional and limited global mapping of Mercury has already yielded valuable science results, elucidating the history and distribution of several types of units and features, such as regional plains, tectonic structures, and pyroclastic deposits. To date, however, no global geological map of Mercury exists, and there is currently no commonly accepted set of standardized unit descriptions and nomenclature. With MESSENGER monochrome image data, we are undertaking the global geological mapping of Mercury at the 1:15M scale applying standard U.S. Geological Survey mapping guidelines. This map will enable the development of the first global stratigraphic column of Mercury, will facilitate comparisons among surface units distributed discontinuously across the planet, and will provide guidelines for mappers so that future mapping efforts will be consistent and broadly interpretable by the scientific community. To date we have incorporated three major datasets into the global geological map: smooth plains units, tectonic structures, and impact craters and basins >20 km in diameter. We have classified most of these craters by relative age on the basis of the state of preservation of morphological features and standard classification schemes first applied to Mercury by the Mariner 10 imaging team. Additional datasets to be incorporated include intercrater plains units and crater ejecta deposits. In some regions MESSENGER color data is used to supplement the monochrome data, to help elucidate different plains units. The final map will be published online, together with a peer-reviewed publication. Further, a digital version of the map, containing individual map layers, will be made publicly available for use within geographic information systems (GISs).

Seismic stratigraphy and depositional history of the Büyükçekmece ...

Indian Academy of Sciences (India)

Denizhan Vardar

2018-02-14

Feb 14, 2018 ... The Marmara Sea is an intra-continental marine basin connected ... The northern shelf areas of the Marmara Sea is ... stratigraphy of this margin have been focused on .... due to shallow gas accumulations. In the ..... Petrol. Geol. Bull. 76 1687–1709. Smith A D, Taymaz T, Oktay F, Yüce H, Alpar B, Basaran.

Geologic repositories for radioactive waste: the nuclear regulatory commission geologic comments on the environmental assessment

International Nuclear Information System (INIS)

Justus, P.S.; Trapp, J.S.; Westbrook, K.B.; Lee, R.; Blackford, M.B.; Rice, B.

1985-01-01

The NRC staff completed its review of the Environmental Assessments (EAs) issued by the Department of Energy (DOE) in December, 1984, in support of the site selection processes established by the Nuclear Waste Policy Act of 1982 (NWPA). The EAs contain geologic information on nine sites that DOE has identified as potentially acceptable for the first geologic repository in accordance with the requirements of NWPA. The media for the sites vary from basalt at Hanford, Washington, tuff at Yucca Mountain, Nevada, bedded salt in the Palo Duro Basin, Texas and Paradox Basin, Utah, to salt domes in Mississippi and Louisiana. Despite the diversity in media there are common areas of concern for all sites. These include; structural framework and pattern, rates of tectonic and seismic activity, characterization of subsurface features, and stratigraphic thickness, continuity and homogeneity. Site-specific geologic concerns include: potential volcanic and hydrothermal activity at Yucca Mountain, potential hydrocarbon targets and deep basalt and sub-basalt structure at Hanford, and potential dissolution at all salt sites. The NRC comments were influenced by the performance objectives and siting criteria of 10 CFR Part 60 and the environmental protection criteria in 40 CFR Part 191, the applicable standards proposed by EPA. In its review the NRC identified several areas of geologic concern that it recommended DOE re-examine to determine if alternative or modified conclusions are appropriate

Surficial geology and stratigraphy of Pleistocene Lake Manix, San Bernardino County, California

Science.gov (United States)

Reheis, Marith C.; Redwine, Joanna R.; Wan, Elmira; McGeehin, John P.; VanSistine, D. Paco

2014-01-01

Pluvial Lake Manix and its surrounding drainage basin, in the central Mojave Desert of California, has been a focus of paleoclimate, surficial processes, and neotectonic studies by the U.S. Geological Survey (USGS) since about 2004. The USGS initiated studies of Lake Manix deposits to improve understanding of the paleoclimatic record and the shifts in atmospheric circulation that controlled precipitation in the Mojave Desert. Until approximately 25,000 years ago, Lake Manix was the terminus of the Mojave River, which drains northeasterly from the San Bernardino Mountains; the river currently terminates in the Soda Lake and Silver Lake playas. Pleistocene Lake Manix occupied several subbasins at its maximum extent. This map focuses on the extensive exposures created by incision of the Mojave River and its tributaries into the interbedded lacustrine and alluvial deposits within the central (Cady) and northeastern (Afton) subbasins of Lake Manix, and extends from the head of Afton Canyon to Manix Wash. The map illuminates the geomorphic development and depositional history of the lake and alluvial fans within the active tectonic setting of the eastern California shear zone, especially interactions with the left-lateral Manix fault. Lake Manix left an extraordinarily detailed but complex record of numerous transgressive-regressive sequences separated by desiccation and deposition of fan, eolian, and fluvial deposits, and punctuated by tectonic movements and a catastrophic flood that reconfigured the lake basin. Through careful observation of the intercalated lacustrine and fan sequences and by determining the precise elevations of unit contacts, this record was decoded to understand the response of the lake and river system to the interplay of climatic, geomorphic, and tectonic forces. These deposits are exposed in steep badland topography. Mapping was carried out mostly at scales of 1:12,000, although the map is presented at 1:24,000 scale, and employs custom unit

Crustal structural survey for the state of Minas Gerais, Brazil, utilizing geophysical and geological information

International Nuclear Information System (INIS)

Haralyi, N.L.E.; Hasui, Y.; Mioto, J.A.; Hamza, V.M.

1985-01-01

Gravity, Magnetic (airborne, Magnet and Magsat), heat flow and seismicity available data for the state of Minas Gerais and adjacent regions is here analyzed, discussed and integrated with geologic information. The Late Archean crustal structure is defined as blocks of granite-greenstone separated by belts of high-grade terrains. The belts in eastern and southern Minas Gerais represent the lower parts of the Vitoria, Sao Paulo and Parana Blocks, which were up thrusted over the Brasilia Block through low-angle ductile simple shear Zones. That regional structure is cut and somewhat displaced by NW, ENE, NE and Ns fault sets. These faults are mostly related to the Transamazonian Event, and their geological expression appears to be as high-angle ductile simple shear zones. The development of the Middle/upper proterozoic folded sequences, the incidence of the Brasiliano/Uruacuano thermo tectonic events and the geometry of the Sao Francisco Craton were highly influenced by the preexistent weakness zones. The high-grade terrains, the borders of the Brasilia Block and the Transamazonian lineaments have been preferentially affected. The tectono-magmatic manifestations of the Wealdenian Reactivation, related to the opening of the Atlantic Ocean, occurred mostly among the uplifted zones (Alto Paranaiba Uplift) that developed partially until the rift stage (Mantiqueira Uplift). These processes clearly reveal the influence of the old structures of the state of Minas Gerais. The Mantiqueira Uplift presents a more accentuated seismic activity and thermal flow regime than the neighboring regions, so corresponding to the present less stable area of Minas Gerais. (DJM) [pt

Geologic studies in the Sierra de Pena Blanca, Chihuahua, Mexico

Science.gov (United States)

Reyes-Cortes, Ignacio Alfonso

The Sierra del Cuervo has been endowed with uranium mineralization, which has attracted many geological studies, and recently the author was part of a team with the goal of selecting a site of a radioactive waste repository. The first part of the work adds to the regional framework of stratigraphy and tectonics of the area. It includes the idea of a pull apart basin development, which justifies the local great thickness of the Cuervo Formation. It includes the regional structural frame work and the composite stratigraphic column of the Chihuahua Trough and the equivalent Cretaceous Mexican Sea. The general geologic features of the NE part of the Sierra del Cuervo are described, which include the folded ignimbrites and limestones in that area; the irregular large thicknesses of the Cuervo Formation; and the western vergence of the main folding within the area. Sanidine phenocrystals gave ages of 54.2 Ma and 51.8 Ma ± 2.3 Ma. This is the first time these dates have been reported in print. This age indicates a time before the folded structures which outcrop in the area, and 44 Ma is a date after the Cuervo Formation was folded. The Hidalgoan orogeny cycle affected the rocks between this lapse of time. Since then the area has been partially affected by three tensional overlapped stages, which resulted in the actual Basin and Range physiography. The jarosite related to the tectonic activity mineralization has been dated by the Ar-Ar method and yields an age of 9.8 Ma. This is the first report of a date of mineralization timing at Pena Blanca Uranium District in the Sierra del Cuervo. These are some of the frame work features that justify the allocation of a radioactive waste repository in the Sierra del Cuervo. An alluvial fan system within the Boquilla Colorada microbasin was selected as the best target for more detailed site assessment. The study also included the measurement of the alluvium thicknesses by geoelectric soundings; studies of petrography and weathered

Geological Structure and Gold Mineralization of Carbonaceous Deposits of the Tyotechnaya Mountain (South Urals

Directory of Open Access Journals (Sweden)

A. V. Snachev

2018-03-01

Full Text Available This paper considers the geological structure of the northern part of the East-Urals Trough. Particular attention is paid to the Kosobrodskaya Formation, where the carbonaceous deposits are most abundant. It was found that the gold in the black shales of the Tyotechnaya Mountain is associated with the intensively dislocated, silicified and sulfidised rocks struck with the diorite porphyry of the Birgildin-Tomino Complex. Channel sampling on the number of wells showed the gold grades up to 1.5 g/t that allows suggesting the setting up of new gold deposit.

A Knowledge-Driven Geospatially Enabled Framework for Geological Big Data

OpenAIRE

Liang Wu; Lei Xue; Chaoling Li; Xia Lv; Zhanlong Chen; Baode Jiang; Mingqiang Guo; Zhong Xie

2017-01-01

Geologic survey procedures accumulate large volumes of structured and unstructured data. Fully exploiting the knowledge and information that are included in geological big data and improving the accessibility of large volumes of data are important endeavors. In this paper, which is based on the architecture of the geological survey information cloud-computing platform (GSICCP) and big-data-related technologies, we split geologic unstructured data into fragments and extract multi-dimensional f...

Integrated stratigraphy of the late Campanian - Maastrichtian in the Danish Basin

DEFF Research Database (Denmark)

Boussaha, Myriam; Thibault, Nicolas Rudolph; Stemmerik, Lars

2016-01-01

New stratigraphic (calcareous nannofossils and carbon isotope) and sedimentological results from the upper Campanian – Maastrichtian of the Stevns-2 core, Denmark, allow for regional correlations and building of a solid age-model with the definition of 17 stratigraphic tie-points in the Danish Ba...... is presented for the Danish Basin, calibrated in age and correlated to high-resolution carbon isotope stratigraphy. Common, regional changes in sediment accumulation rates highlight trends that appear linked to climatic conditions....

Geological survey by high resolution electrical survey on granite areas

International Nuclear Information System (INIS)

Sugimoto, Yoshihiro; Yamada, Naoyuki

2002-03-01

As an Integral part of the geological survey in 'The study of the regions ground water flow system' that we are carrying out with Tono Geoscience Center, we proved the relation between the uncontinuation structure such as lineament in the base rock and resistivity structure (resistivity distribution), for the purpose of that confirms the efficacy of the high resolution electrical survey as geological survey, we carried out high resolution electrical survey on granite area. We obtained the following result, by the comparison of resistivity distribution with established geological survey, lineament analysis and investigative drilling. 1. The resistivity structure of this survey area is almost able to classify it into the following four range. 1) the low resistivity range of 50-800 Ωm, 2) The resistivity range like the middle of 200-2000 Ωm, 3) The high resistivity range of 2000 Ωm over, 4) The low resistivity range of depth of the survey line 400-550 section. 2. The low resistivity range of 4) that correspond with the established geological data is not admitted. 3. It was confirmed that resistivity structure almost correspond to geological structure by the comparison with the established data. 4. The small-scale low resistivity area is admitted in the point equivalent to the lineament position of established. 5. We carried out it with the simulation method about the low resistivity range of 4). As a result, it understood that it has the possibility that the narrow ratio low resistivity area is shown as the wide ratio resistivity range in the analysis section. In the survey in this time, it is conceivable that the resistivity distribution with the possibility of the unhomogeneous and uncontinuation structure of the base rock is being shown conspicuously, the efficacy of the high resolution resistivity survey as geological survey on granite was shown. (author)

The Seabed and Shallow Geology Mapping of the Porcupine Bank, West of Ireland

Science.gov (United States)

Thébaudeau, B.; Monteys, X.; McCarron, S. G.

2016-02-01

The "Porcupine Bank" is a bathymetric high of over 40,000 km2 linked to the western shelf of Ireland which lies between 51-54° N and 11-15° W approximately 100 km west of Ireland. Water depths are as shallow as 145 m over the "Porcupine Ridge". The Bank's location on the north eastern fringe of the Atlantic Ocean, in a critical position between the shelf edge and the main land and along the line of the Polar Front, means it may contain significant indications of glacial/interglacial changes in northern hemisphere climate and in North Atlantic Ocean circulation. But it also means that it consists of strategically important marine environments with very likely future developmental pressures. Peer-reviewed publications on the geology of the Bank are very limited and this current state of knowledge will hamper any marine ecosystem research and protection. This paper will describe the first results of a research project aiming at filling the gap of our understanding of the region's shallow geology and subseabed resources and characteristics. As a first step, seabed geomorphology mapping using high resolution MBES and sub bottom data have highlighted a wealth of glacially derived features such as iceberg scours and elongated ridges whose formation could be directly influenced by the presence of ice on or nearby the bank. Other features interpreted as sand waves could help understand relict or modern currents. In addition to these surface features, this paper introduces recent geological mapping of the shallow stratigraphy of the bank using 2D seismic and sub bottom profiler data collected at a high density correlated with recently collected vibro-cores. The seismic units and corresponding lithofacies (some with radiocarbon dates) are consistently described and a regional correlation built.

Major episodes of geologic change - Correlations, time structure and possible causes

Science.gov (United States)

Rampino, Michael R.; Caldeira, Ken

1993-01-01

Published data sets of major geologic events of the past about 250 Myr (extinction events, sea-level lows, continental flood-basalt eruptions, mountain-building events, abrupt changes in sea-floor spreading, ocean-anoxic and blackshale events and the largest evaporite deposits) have been synthesized (with estimated errors). These events show evidence for a statistically significant periodic component with an underlying periodicity, formally equal to 26.6 Myr, and a recent maximum, close to the present time. The cycle may not be strictly periodic, but a periodicity of about 30 Myr is robust to probable errors in dating of the geologic events. The intervals of geologic change seem to involve jumps in sea-floor spreading associated with episodic continental rifting, volcanism, enhanced orogeny, global sea-level changes and fluctuations in climate. The period may represent a purely internal earth-pulsation, but evidence of planetesimal impacts at several extinction boundaries, and a possible underlying cycle of 28-36 Myr in crater ages, suggests that highly energetic impacts may be affecting global tectonics. A cyclic increase in the flux of planetesimals might result from the passage of the Solar System through the central plane of the Milky Way Galaxy - an event with a periodicity and mean phasing similar to that detected in the geologic changes.

Geological hazard monitoring system in Georgia

Science.gov (United States)

Gaprindashvili, George

2017-04-01

Georgia belongs to one of world's most complex mountainous regions according to the scale and frequency of Geological processes and damage caused to population, farmlands, and Infrastructure facilities. Geological hazards (landslide, debrisflow/mudflow, rockfall, erosion and etc.) are affecting many populated areas, agricultural fields, roads, oil and gas pipes, high-voltage electric power transmission towers, hydraulic structures, and tourist complexes. Landslides occur almost in all geomorphological zones, resulting in wide differentiation in the failure types and mechanisms and in the size-frequency distribution. In Georgia, geological hazards triggered by: 1. Activation of highly intense earthquakes; 2. Meteorological events provoking the disaster processes on the background of global climatic change; 3. Large-scale Human impact on the environment. The prediction and monitoring of Geological Hazards is a very wide theme, which involves different researchers from different spheres. Geological hazard monitoring is essential to prevent and mitigate these hazards. In past years in Georgia several monitoring system, such as Ground-based geodetic techniques, Debrisflow Early Warning System (EWS) were installed on high sensitive landslide and debrisflow areas. This work presents description of Geological hazard monitoring system in Georgia.

The geologic character of nappe structure and its relation to uranium mineralization of Xiangshan ore-field in the middle of Jiangxi Province

International Nuclear Information System (INIS)

Zhou Yulong; Yang Song

2012-01-01

Started with the spatial distribution of nappe structure, the geologic features are discussed and its effect on uranium mineralization in systematically summarized for Xiangshan ore-field in the middle of Jiangxi Province. The nappe structure not only formed a 'cross-over' lithologic combination which creates a network system which can connect, transport, migrate the mineralized matter, but also formed some close or semi-close geologic setting beneath the nappe which can act as the store ore shield space for the mineralized liquid to form uranium deposit. The mineralization is concentrated at the varied place of occurrences or shape of sub-volcanic rocks and the intersection of concealed overthrust and NE strike basic fractures. (authors)

The sedimentary record and petrophysical logs from the Spanish Central Pyrenees: Implications for paleoclimate change in the Early Devonian

Czech Academy of Sciences Publication Activity Database

Slavík, Ladislav; Valenzuela-Ríos, J. I.; Hladil, Jindřich; Chadimová, Leona; Liao, J-Ch.; Hušková, Aneta; Calvo, H.; Hrstka, Tomáš

2015-01-01

Roč. 21, - (2015), s. 350-350 ISSN 1608-8166. [International Congress on Stratigraphy /2./. STRATI 2015. 19.07.2015-23.07.2015, Graz] Institutional support: RVO:67985831 Keywords : stratigraphy * Early Devonian * sedimentary record * paleoclimate change * Spanish Central Pyrenees Subject RIV: DB - Geology ; Mineralogy http://www.zobodat.at/pdf/Ber-Inst-Erdwiss-Univ-Graz_21_0001-0437.pdf

Geometric analysis of alternative models of faulting at Yucca Mountain, Nevada

International Nuclear Information System (INIS)

Young, S.R.; Stirewalt, G.L.; Morris, A.P.

1993-01-01

Realistic cross section tectonic models must be retrodeformable to geologically reasonable pre-deformation states. Furthermore, it must be shown that geologic structures depicted on cross section tectonic models can have formed by kinematically viable deformation mechanisms. Simple shear (i.e., listric fault models) is consistent with extensional geologic structures and fault patterns described at Yucca Mountain, Nevada. Flexural slip models yield results similar to oblique simple shear mechanisms, although there is no strong geological evidence for flexural slip deformation. Slip-line deformation is shown to generate fault block geometrics that are a close approximation to observed fault block structures. However, slip-line deformation implies a degree of general ductility for which there is no direct geological evidence. Simple and hybrid 'domino' (i.e., planar fault) models do not adequately explain observed variations of fault block dip or the development of 'rollover' folds adjacent to major bounding faults. Overall tectonic extension may be underestimated because of syn-tectonic deposition (growth faulting) of the Tertiary pyroclastic rocks that comprise Yucca Mountain. A strong diagnostic test of the applicability of the domino model may be provided by improved knowledge of Tertiary volcanic stratigraphy

Geology of the Fox Hills Formation (late Cretaceous) in the Williston Basin of North Dakota, with reference to uranium potential. Report of investigation No. 55

International Nuclear Information System (INIS)

Cvancara, A.M.

1976-01-01

The Fox Hills Formation is a marine and brackish sequence of primarily medium and fine clastics within the Late Cretaceous Montana Group. In the Williston basin of North Dakota, four members (in ascending order) are recognized: Trail City, Timber Lake, Iron Lightning (with Bullhead and Colgate lithofacies), and Linton. The Fox Hills conformably overlies the Pierre Shale and conformably and disconformably underlies and interfingers with the Hell Creek Formation; it occurs in about the western two-thirds of the state. The geology of the Fox Hills Formation in North Dakota, and the stratigraphy of which is based on previous surface information and recent subsurface data, are summarized, and its potential for uranium is evaluated

Interactions Between Stratigraphy and Interfacial Properties on Flow and Trapping in Geologic Carbon Storage

Science.gov (United States)

Liang, Bo; Clarens, Andres F.

2018-01-01

Gas leakage from geologic carbon storage sites could undermine the long-term goal of reducing emissions to the atmosphere and negatively impact groundwater resources. Despite this, there remain uncertainties associated with the transport processes that would govern this leakage. These stem from the complex interaction between governing forces (e.g., gravitational, viscous, and capillary), the heterogeneous nature of the porous media, and the characteristic length scales of these leakage events, all of which impact the CO2 fluid flow processes. Here we assessed how sub-basin-scale horizons in porous media could impact the migration and trapping of a CO2 plume. A high-pressure column packed with two layers of sand with different properties (e.g., grain size and wettability) was used to create a low-contrast stratigraphic horizon. CO2 in supercritical or liquid phase was injected into the bottom of the column under various conditions (e.g., temperature, pressure, and capillary number) and the transport of the resulting plume was recorded using electrical resistivity. The results show that CO2 trapping was most strongly impacted by shifting the wettability balance to mixed-wet conditions, particularly for residual saturation. A 16% increase in the cosine of the contact angle for a mixed-wet sand resulted in nearly twice as much residual trapping. Permeability contrast, pressure, and temperature also impacted the residual saturation but to a lesser extent. Flow rate affected the dynamics of saturation profile development, but the effect is transient, suggesting that the other effects observed here could apply to a broad range of leakage conditions.

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

-registration, depth correction, etc.) each geophysical profile was evaluated by matching the core data. Applying traditional geophysical techniques, the best profiles were inverted using the core data creating two-dimensional (2-D) stratigraphic regolith models for each transect, and evaluated using independent validation. Next, in a test of an alternative method borrowed from digital soil mapping, the best preprocessed geophysical profiles were co-registered and stratigraphic models for each property created using multivariate environmental correlation. After independent validation, the qualities of the latest models were compared to the traditionally derived 2-D inverted models. Finally, the best overall stratigraphic models were used in conjunction with local environmental data (e.g. geology, geochemistry, terrain, soils) to create conceptual regolith hillslope models for each transect highlighting important features and processes, e.g. morphology, hydropedology and weathering characteristics. Results are presented with recommendations regarding the use of geophysics in modelling regolith stratigraphy at fine scales.

Geological events in submerged areas: attributes and standards in the EMODnet Geology Project

Science.gov (United States)

Fiorentino, A.; Battaglini, L.; D'Angelo, S.

2017-12-01

EMODnet Geology is a European Project which promotes the collection and harmonization of marine geological data mapped by various national and regional mapping projects and recovered in the literature, in order to make them freely available through a web portal. Among the several features considered within the Project, "Geological events and probabilities" include submarine landslides, earthquakes, volcanic centers, tsunamis, fluid emissions and Quaternary faults in European Seas. Due to the different geological settings of European sea areas it was necessary to elaborate a comprehensive and detailed pattern of Attributes for the different features in order to represent the diverse characteristics of each occurrence. Datasets consist of shapefiles representing each event at 1:250,000 scale. The elaboration of guidelines to compile the shapefiles and attribute tables was aimed at identifying parameters that should be used to characterize events and any additional relevant information. Particular attention has been devoted to the definition of the Attribute table in order to achieve the best degree of harmonization and standardization according to the European INSPIRE Directive. One of the main objectives is the interoperability of data, in order to offer more complete, error-free and reliable information and to facilitate exchange and re-use of data even between non-homogeneous systems. Metadata and available information collected during the Project is displayed on the Portal (http://www.emodnet-geology.eu/) as polygons, lines and points layers according to their geometry. By combining all these data it might be possible to elaborate additional thematic maps which could support further research as well as land planning and management. A possible application is being experimented by the Geological Survey of Italy - ISPRA which, in cooperation with other Italian institutions contributing to EMODnet Geology, is working at the production of an update for submerged areas

OneGeology- A Global Geoscience Data Platform

Science.gov (United States)

Harrison, M.; Komac, M.; Duffy, T.; Robida, F.; Allison, M. L.

2014-12-01

OneGeology (1G) is an initiative of Geological Survey Organisations (GSOs) around the globe that dates back to 2007. Since then, OneGeology has been a leader in developing geological online map data using GeoSciML- an international interoperability standard for the exchange of geological data. Increased use of this new standard allows geological data to be shared and integrated across the planet among organisations. One of the goals of OneGeology is an exchange of know-how with the developing world, shortening the digital learning curve. In autumn 2013 OneGeology was transformed into a Consortium with a clearly defined governance structure, making it more transparent, its operation more sustainable and its membership more open where in addition to GSOs, other types of organisations that create and use geoscience data can join and contribute. The next stage of the OneGeology initiative is focused on increasing the openness and richness of that data from individual countries to create a multi-thematic global geological data resource about the rocks beneath our feet. Authoritative geoscience information will help to mitigate natural disasters, explore for resources (water, minerals and energy) and identify risks to human health on a planetary scale with the aim of 1G to increase awareness of the geosciences and their relevance among professionals and general public- to be part of the solution. We live in a digital world that enables prompt access to vast amounts of open access data. Understanding our world, the geology beneath our feet and environmental challenges related to geology calls for accessibility of geoscience data and the OneGeology Portal (portal.onegeology.org) is the place to find them.

Stratigraphy and age estimate of Neogene shallow marine fossiliferous deposits in Brunei Darussalam (Ambug Hill, Tutong district)

Science.gov (United States)

Kocsis, László; Briguglio, Antonino; Roslim, Amajida; Razak, Hazirah; Ćorić, Stjepan; Frijia, Gianluca

2018-06-01

The Ambug Hill in Brunei is an exceptional geological site where a series of siliciclastic rocks crops out with some layers extremely rich in marine fossils. Such fossiliferous outcrops are extremely rare in the northern part of Borneo and their description is of primary importance as their fossil content can be used to correlate the regional depositional sequences with global biostratigraphic zonations. In this work we present for the first time a detailed sedimentary profile completed with Sr-isotopes and biostratigraphic dating. The succession is divided into four sedimentary units. The first unit comprises bioturbated sandstone followed by a second unit of clay-silt rich levels whose first 9.5 m contain rich marine fossil assemblages. Calcareous nannoplankton data indicate a Late Tortonian - Early Messinian (NN11) age, which is confirmed by Sr-isotope dating derived from bivalves giving a numerical age range from 8.3 to 6.2 My. After a major emersion surface, the third sedimentary unit of sand- and siltstone lacks suitable fossils for bio- and isotope stratigraphy. The age of emersion and the related sedimentary gap can be either correlated with the Me1 (7.25 My) or the Me2 (5.73 My) sequence boundary. A fourth, thin sedimentary unit is recognized on the top of the profile with silt- and claystone beds without age diagnostic remains and calcareous fossils.

Nové vulkanologické poznatky z Litoměřicka

Czech Academy of Sciences Publication Activity Database

Cajz, Vladimír

-, - (2004), s. 16-19 ISSN 0514-8057 R&D Projects: GA AV ČR IAA3013302 Keywords : ignimbrites * quartzites * stratigraphy Subject RIV: DB - Geology ; Mineralogy http://www.geology.cz/zpravy/obsah/2003/zpravy-o-vyzkumech-2003-str-016-19.pdf

Geological and Structural Inferences from Satellite Images in Parts of Deccan basalt covered regions of Central India

Science.gov (United States)

Harinarayana, Tirumalachetty; Borra, Veeraiah; Basava, Sharana; Suryabali, Singh

In search of new areas for hydrocarbon exploration, integrated ground geophysical studies have been taken up in Central India with seismic, magnetotellurics, deep resistivity and gravity surveys. Since the region is covered with basalt and well known for its intensive tectonic activity, remote sensing method seems to have value addition to the subsurface information derived from geophysical, geological and tectonic studies. The Narmada and Tapti rift zone and Deccan basalt covered regions of Central India, stems from its complexity. A Resourcesat-1 (IRS- P6) LISS-III satellite images covering an area of approximately 250,000 sq. km corresponding to the region in and around Baroda(Vadodara), Indore, Nandurbar, Khandwa, Akot, Nasik, Aurangabad, Pune and Latur in Central India was digitally processed and interpreted to present a schematic map of the geology and elucidate the structural fabric of the region. From our study, the disposition of the intensive dyke system, various faults and other lineaments in the region are delineated. Ground truth studies have shown good correlation with lineaments/dykes indicated in remote sensing studies and have revealed distinct ENE-WSW trending lineaments, dykes which are more prominent near the Narmada and Tapti river course. Evolution of these features with Deccan volcanism is discussed with available geochronological data set. These findings are significant in relation to structural data and form a part of the geo-structural database for ground surveys.

Scientific Journals as Fossil Traces of Sweeping Change in the Structure and Practice of Modern Geology

Directory of Open Access Journals (Sweden)

H. L. Vacher

2008-01-01

Full Text Available In our attempts to track changes in geological practice over time and to isolate the source of these changes, we have found that they are largely connected with the germination of new geologic subdisciplines. We use keyword and title data from articles in 68 geology journals to track the changes in influence of each subdiscipline on geology over all. Geological research has shifted emphasis over the study period, moving away from economic geology and petroleum geology, towards physics- and chemistry-based topics. The Apollo lunar landings had as much influence on the topics and practice of geological research as the much-cited plate-tectonics revolution. These results reflect the barely-tangible effects of the changes in vocabulary and habit of thought that have pervaded the substance of geology. Geological literature has increased in volume and specialization, resulting in a highly fragmentary literature. However, we infer that "big science," characterized by large amounts of funding, collaboration, and large logistical investments, makes use of this specialization and turns "twigging" into a phenomenon that enhances, rather than inhibits, the enterprise of research.

Upper Campanian–Maastrichtian nannofossil biostratigraphy and high-resolution carbon-isotope stratigraphy of the Danish Basin

DEFF Research Database (Denmark)

Thibault, Nicolas Rudolph; Harlou, Rikke; Schovsbo, Niels

2012-01-01

High-resolution carbon isotope stratigraphy of the upper Campanian – Maastrichtian is recorded in the Boreal Realm from a total of 1968 bulk chalk samples of the Stevns-1 core, eastern Denmark. Isotopic trends are calibrated by calcareous nannofossil bio-events and are correlated with a lower...

Geologic Reconnaissance and Lithologic Identification by Remote Sensing

Science.gov (United States)

remote sensing in geologic reconnaissance for purposes of tunnel site selection was studied further and a test case was undertaken to evaluate this geological application. Airborne multispectral scanning (MSS) data were obtained in May, 1972, over a region between Spearfish and Rapid City, South Dakota. With major effort directed toward the analysis of these data, the following geologic features were discriminated: (1) exposed rock areas, (2) five separate rock groups, (3) large-scale structures. This discrimination was accomplished by ratioing multispectral channels.

Improving the Monitoring, Verification, and Accounting of CO{sub 2} Sequestered in Geologic Systems with Multicomponent Seismic Technology and Rock Physics Modeling

Energy Technology Data Exchange (ETDEWEB)

Alkan, Engin; DeAngelo, Michael; Hardage, Bob; Sava, Diana; Sullivan, Charlotte; Wagner, Donald

2012-12-31

Research done in this study showed that P-SV seismic data provide better spatial resolution of geologic targets at our Appalachian Basin study area than do P-P data. This finding is important because the latter data (P-P) are the principal seismic data used to evaluate rock systems considered for CO{sub 2} sequestration. The increase in P-SV{sub 1} resolution over P-P resolution was particularly significant, with P-SV{sub 1} wavelengths being approximately 40-percent shorter than P-P wavelengths. CO{sub 2} sequestration projects across the Appalachian Basin should take advantage of the increased resolution provided by converted-shear seismic modes relative to P-wave seismic data. In addition to S-wave data providing better resolution of geologic targets, we found S-wave images described reservoir heterogeneities that P-P data could not see. Specifically, a channel-like anomaly was imaged in a key porous sandstone interval by P-SV{sub 1} data, and no indication of the feature existed in P-P data. If any stratigraphic unit is considered for CO{sub 2} storage purposes, it is important to know all heterogeneities internal to the unit to understand reservoir compartmentalization. We conclude it is essential that multicomponent seismic data be used to evaluate all potential reservoir targets whenever a CO{sub 2} storage effort is considered, particularly when sequestration efforts are initiated in the Appalachian Basin. Significant differences were observed between P-wave sequences and S- wave sequences in data windows corresponding to the Oriskany Sandstone, a popular unit considered for CO{sub 2} sequestration. This example demonstrates that S-wave sequences and facies often differ from P-wave sequences and facies and is a principle we have observed in every multicomponent seismic interpretation our research laboratory has done. As a result, we now emphasis elastic wavefield seismic stratigraphy in our reservoir characterization studies, which is a science based on the

The regional geological and structural setting of the uraniferous granitic provinces of Southern Africa

International Nuclear Information System (INIS)

Jacob, R.E.; Corner, B.; Brynard, H.J.

1986-01-01

Uranium-bearing granites, comprising both potentially economic deposits and source rocks for uranium deposits is duricrustal and sedimentary sequences, are confined chiefly to the mobile belts of Southern Africa and to the Cape granites emplaced during late Precambrian times. The direct uranium potential of the mobile belts, i.e. the Damara, Namaqua-Natal and Limpopo belts, decreases with an increase in the age of associated ensialic diastrophism. This review paper is thus mainly confined to the Damara Belt, although a brief discussion of the potential of the Namaqua Belt is presented. Aspects of the Damara Belt that are discussed in detail, with particular reference to the occurrence of uraniferous granite, include regional tectonic setting, stratigraphy, structure, metamorphism and the patterns and origin of the uranium mineralization. Initial concentrations of uranium in basement and Nosib rocks have led, through ultrametamorphism and fractionation, to uraniferous granites of both economic and sub-economic grade. These granites, in turn, have acted as source of secondary mineralization in overlying superficial calcareous and gypsiferous deposits. The Damara Belt thus provides a good example of multicyclic processes of ore formation. With regard to the uraniferous granites of Namaqualand it is concluded that the porphyroblastic gneisses and late-intrusive Concordia granites, although not of direct economic interest, represent major sources of uranium for secondary superficial deposits. Smaller bodies of late-phase differentiates associated with the Concordia granitic gneiss may themselves, however, represent potentially economically viable deposits

Structural geology of the North and Middle Caspian sea on the new geophysical data interpretation

International Nuclear Information System (INIS)

Boris, V.S; Rais, V.Sh; Victor, L.U

2002-01-01

Full text:A structural and tectonic map of the North and Middle Caspian Sea is made on the basis of seismic and other geological and geophysical data analysis. According to the plotting results the total amplitude range of the heterogeneous basement depths are in the North Caspian Sea (Ukatnensky depression-over 12 km and Prorva depression-over 16 km). In the middle Caspian Sea the deppest basement point is supposed in Sulak basin (over 12 km). The least basement depths are marked in Karpinsky ridge,Buzachinky and Karabogazsky arches (1-3 km). On the whole the morphology and structure of the basement confirms the conclusion previously made by many researches that the Caspian Sea is a heterogeneous depression superimposed on the junction of regional tectonic elements of various ages.The ancient East-European platform represented by Pricaspiisky depression (Donetsko-Astrakhanskaya fault system limits the latter in the south) is situated on the North. The middle Caspian Sea is occupied with the offshore continuation of Terek-Caspian foredeep is represented by Sulak basin clearly limited in the south by a system of upthrusts and thrusts falling under North Caucasus foreland.Geological interpretation of the Yuzhmorgeologiya Center new geophysical data allows making an assumption about the biohermexistence within TriassicSea sediments on Kuma-Manychsky depression offshore continuation. Seismic exploration works show strike-slip faults and thrust structure development within the sedimentary cover on the offshore continuation of Karpinsky ridge.Some strike-slipped blocks are separated by left-side shifts of the northeast stretch.The pool location at the left-side (east) blocks of the shift areas is marked.

Geological study of radioactive waste repositories

International Nuclear Information System (INIS)

Oyama, Takahiro; Kitano, Koichi

1987-01-01

The investigation of the stability and the barrier efficiency of the deep underground radioactive waste repositories become a subject of great concern. The purpose of this paper is to gather informations on the geology, engineering geology and hydrogeology in deep galleries in Japan. Conclusion can be summarised as follows: (1) The geological structure of deep underground is complicated. (2) Stress in deep underground is greatly affected by crustal movement. (3) Rock-burst phenomena occur in the deep underground excavations. (4) In spite of deep underground, water occasionally gush out from the fractured zone of rock mass. These conclusion will be useful for feasibility study of underground waste disposal and repositories in Japan. (author)

Elements of the geological structure of the Western Siberian platform determined from a review of fine-scale satellite photographs in oil and gas prospecting research

Energy Technology Data Exchange (ETDEWEB)

Borovskii, V V; Klopov, A L; Peskovskii, I D; Podsosova, L L

1980-01-01

Dislocations with breaks in continuity and annular objects are identified on fine-scale satellite photographs within the region of the Western Siberian platform. Based on an integrated interpretation of the geological and geophysical data, it is predicted that there exists a relation between the annular objects and the geological structure of deep portions of the earth's crust, the pre-Jurassic basement, and certain levels of the platform mantle. Procedural techniques for the use of magnetic and gravitional data for the purpose of obtaining information about the geological nature of the identified objects are considered.

Geologic mapping of Kentucky; a history and evaluation of the Kentucky Geological Survey--U.S. Geological Survey Mapping Program, 1960-1978

Science.gov (United States)

Cressman, Earle Rupert; Noger, Martin C.

1981-01-01

. Paleontologists and stratigraphers of the U.S. Geological Survey cooperated closely with the program. Paleontologic studies were concentrated in the Ordovician of central Kentucky, the Pennsylvanian of eastern and western Kentucky, and the Mesozoic and Cenozoic of westernmost Kentucky. In addition to financial support, the Kentucky Geological Survey provided economic data, stratigraphic support, and drillhole records to the field offices. Geologists of the State Survey made subsurface structural interpretations, constructed bedrock topography maps, and mapped several quadrangles. Some of the problems encountered were the inadequacy of much of the existing stratigraphic nomenclature, the uneven quality of some of the mapping, and the effects of relative isolation on the professional development of some of the geologists. The program cost a total of $20,927,500. In terms of 1960 dollars, it cost $16,035,000; this compares with an original estimate of $12,000,000. Although it is difficult to place a monetary value on the geologic mapping, the program has contributed to newly discovered mineral wealth, jobs, and money saved by government and industry. The maps are used widely in the exploration for coal, oil and gas, fluorspar, limestone, and clay. The maps are also used in planning highways and locations of dams, in evaluating foundation and excavation conditions, in preparing environmental impact statements, and in land-use planning.

Three-dimensional Subsurface Geological Modeling of the Western Osaka Plane based on Borehole Data

Science.gov (United States)

Nonogaki, S.; Masumoto, S.; Nemoto, T.

2012-12-01

Three-dimensional (3D) geological model of subsurface structure plays an important role in developing infrastructures. In particular, the 3D geological model in urban area is quite helpful to solve social problems such as underground utilization, environmental preservation, and disaster assessment. Over the past few years, many studies have been made on algorithms for 3D geological modeling. However, most of them have given little attention to objectivity of the model and traceability of modeling procedures. The purpose of this study is to develop an algorithm for constructing a 3D geological model objectively and for maintaining high-traceability of modeling procedures. For the purpose of our work, we proposed a new algorithm for 3D geological modeling using gridded geological boundary surfaces and the "logical model of geologic structure". The geological boundary surface is given by a form of Digital Elevation Model (DEM). The DEM is generated based on geological information such as elevation, strike and dip by using a unique spline-fitting method. The logical model of geological structure is a mathematical model that defines a positional relation between geological boundary surfaces and geological units. The model is objectively given by recurrence formula derived from a sequence of geological events arranged in chronological order. We applied the proposed algorithm into constructing a 3D subsurface geological model of the western Osaka Plane, southwest Japan. The data used for 3D geological modeling is a set of borehole data provided by Osaka City and Kansai Geoinformatics Agency. As a result, we constructed a 3D model consistent with the subjective model reported in other studies. In addition, all information necessary for modeling, such as the used geological information, the parameters of surface fitting, and the logical model, was stored in text files. In conclusion, we can not only construct 3D geological model objectively but also maintain high

Relating Gestures and Speech: An analysis of students' conceptions about geological sedimentary processes

Science.gov (United States)

Herrera, Juan Sebastian; Riggs, Eric M.

2013-08-01

Advances in cognitive science and educational research indicate that a significant part of spatial cognition is facilitated by gesture (e.g. giving directions, or describing objects or landscape features). We aligned the analysis of gestures with conceptual metaphor theory to probe the use of mental image schemas as a source of concept representations for students' learning of sedimentary processes. A hermeneutical approach enabled us to access student meaning-making from students' verbal reports and gestures about four core geological ideas that involve sea-level change and sediment deposition. The study included 25 students from three US universities. Participants were enrolled in upper-level undergraduate courses on sedimentology and stratigraphy. We used semi-structured interviews for data collection. Our gesture coding focused on three types of gestures: deictic, iconic, and metaphoric. From analysis of video recorded interviews, we interpreted image schemas in gestures and verbal reports. Results suggested that students attempted to make more iconic and metaphoric gestures when dealing with abstract concepts, such as relative sea level, base level, and unconformities. Based on the analysis of gestures that recreated certain patterns including time, strata, and sea-level fluctuations, we reasoned that proper representational gestures may indicate completeness in conceptual understanding. We concluded that students rely on image schemas to develop ideas about complex sedimentary systems. Our research also supports the hypothesis that gestures provide an independent and non-linguistic indicator of image schemas that shape conceptual development, and also play a role in the construction and communication of complex spatial and temporal concepts in the geosciences.

Pyloniid stratigraphy - A new tool to date tropical radiolarian ooze from the central tropical Indian Ocean

Digital Repository Service at National Institute of Oceanography (India)

Gupta, S.M.

stratigraphy. The multi-taper (MTM) spectral analysis of Pyloniids for the last 485 ka in a core (AAS 2/3) reveals significant climatic cycles at the eccentricity (100 ka), tilt (41 ka) and precession (23 ka) bands. Cross-spectral analyses suggest coherent...

Transforming Spatial Reasoning Skills in the Upper-Level Undergraduate Geoscience Classroom Through Curricular Materials Informed by Cognitive Science Research

Science.gov (United States)

Ormand, C. J.; Shipley, T. F.; Dutrow, B. L.; Goodwin, L. B.; Hickson, T. A.; Tikoff, B.; Atit, K.; Gagnier, K. M.; Resnick, I.

2014-12-01

Spatial visualization is an essential skill in the STEM disciplines, including the geosciences. Undergraduate students, including geoscience majors in upper-level courses, bring a wide range of spatial skill levels to the classroom. Students with weak spatial skills may be unable to understand fundamental concepts and to solve geological problems with a spatial component. However, spatial thinking skills are malleable. As a group of geoscience faculty members and cognitive psychologists, we have developed a set of curricular materials for Mineralogy, Sedimentology & Stratigraphy, and Structural Geology courses. These materials are designed to improve students' spatial skills, and in particular to improve students' abilities to reason about spatially complex 3D geological concepts and problems. Teaching spatial thinking in the context of discipline-based exercises has the potential to transform undergraduate STEM education by removing one significant barrier to success in the STEM disciplines. The curricular materials we have developed are based on several promising teaching strategies that have emerged from cognitive science research on spatial thinking. These strategies include predictive sketching, making visual comparisons, gesturing, and the use of analogy. We have conducted a three-year study of the efficacy of these materials in strengthening the spatial skills of students in upper-level geoscience courses at three universities. Our methodology relies on a pre- and post-test study design, with several tests of spatial thinking skills administered at the beginning and end of each semester. In 2011-2012, we used a "business as usual" approach to gather baseline data, measuring how much students' spatial thinking skills improved in response to the existing curricula. In the two subsequent years we have incorporated our new curricular materials, which can be found on the project website: http://serc.carleton.edu/spatialworkbook/activities.html Structural Geology

Integrated geophysical and geological modelling: insights in the 3D structure and kinematics of the Hercynian Suture Zone in the Champtoceaux area (Brittany, France)

Science.gov (United States)

Martelet, G.; Calcagno, Ph.; Gumiaux, C.; Truffert, C.; Bitri, A.; Gapais, D.; Brun, J. P.

2003-04-01

Using the Editeur Géologique, a software specifically developed for the purpose of 3D geological modelling by the French Geological Survey (BRGM), we model a segment of the Hercynian suture zone of western Europe, in Champtoceaux area (Brittany, western France). The area shows exposures of strongly deformed eclogite-bearing gneisses and micaschists. These units were stacked during collision and exhumed during late Devonian to early Carboniferous times. Regional-scale dextral simple shear accompanied strike-slip movements along the SASZ (South Armorican Shear Zone). It produced a km-scale antiformal structure in the Champtoceaux metamorphic units with a steeply-dipping axial plane and a steeply eastward-plunging axis. Interpretation of the recent Armor2 seismic profile shows that the well-recognized north-dipping early lithological structuration is cross-cut by Carboniferous south-dipping inverse tectonics of crustal extension. In order to precise and extend in 3D the structures interpreted in the seismic profile, we model seven radial gravity profiles throughout Champtoceaux periclinal termination, based on data from the French gravity database. Direct 2D modelling is performed at a crustal scale, based on seismic constraints and geological field observations, as well as density measurements on samples or in drill holes. Input in the Editeur Géologique, the consistency of cross-sections, digitized geological map and structural information (foliation dips) is first checked. From the surface to the Moho, available spatialised 2D information is then interpolated in the whole 3D space using adapted geostatistical analysis. Finally, taking into account densities associated to each modelled geological body, the computation of the 3D gravity effect of the model is compared to the measured Bouguer anomaly, which insures that all complex 3D gravity effects are well taken into account. Results emphasise the usefulness of integrated geological and geophysical 3D modelling

Planetary geology

CERN Document Server

Gasselt, Stephan

2018-01-01

This book provides an up-to-date interdisciplinary geoscience-focused overview of solid solar system bodies and their evolution, based on the comparative description of processes acting on them. Planetary research today is a strongly multidisciplinary endeavor with efforts coming from engineering and natural sciences. Key focal areas of study are the solid surfaces found in our Solar System. Some have a direct interaction with the interplanetary medium and others have dynamic atmospheres. In any of those cases, the geological records of those surfaces (and sub-surfaces) are key to understanding the Solar System as a whole: its evolution and the planetary perspective of our own planet. This book has a modular structure and is divided into 4 sections comprising 15 chapters in total. Each section builds upon the previous one but is also self-standing. The sections are:  Methods and tools Processes and Sources  Integration and Geological Syntheses Frontiers The latter covers the far-reaching broad topics of exo...

Linking geology and microbiology: inactive pockmarks affect sediment microbial community structure.

Science.gov (United States)

Haverkamp, Thomas H A; Hammer, Øyvind; Jakobsen, Kjetill S

2014-01-01

Pockmarks are geological features that are found on the bottom of lakes and oceans all over the globe. Some are active, seeping oil or methane, while others are inactive. Active pockmarks are well studied since they harbor specialized microbial communities that proliferate on the seeping compounds. Such communities are not found in inactive pockmarks. Interestingly, inactive pockmarks are known to have different macrofaunal communities compared to the surrounding sediments. It is undetermined what the microbial composition of inactive pockmarks is and if it shows a similar pattern as the macrofauna. The Norwegian Oslofjord contains many inactive pockmarks and they are well suited to study the influence of these geological features on the microbial community in the sediment. Here we present a detailed analysis of the microbial communities found in three inactive pockmarks and two control samples at two core depth intervals. The communities were analyzed using high-throughput amplicon sequencing of the 16S rRNA V3 region. Microbial communities of surface pockmark sediments were indistinguishable from communities found in the surrounding seabed. In contrast, pockmark communities at 40 cm sediment depth had a significantly different community structure from normal sediments at the same depth. Statistical analysis of chemical variables indicated significant differences in the concentrations of total carbon and non-particulate organic carbon between 40 cm pockmarks and reference sample sediments. We discuss these results in comparison with the taxonomic classification of the OTUs identified in our samples. Our results indicate that microbial communities at the sediment surface are affected by the water column, while the deeper (40 cm) sediment communities are affected by local conditions within the sediment.

Linking geology and microbiology: inactive pockmarks affect sediment microbial community structure.

Directory of Open Access Journals (Sweden)

Thomas H A Haverkamp

Full Text Available Pockmarks are geological features that are found on the bottom of lakes and oceans all over the globe. Some are active, seeping oil or methane, while others are inactive. Active pockmarks are well studied since they harbor specialized microbial communities that proliferate on the seeping compounds. Such communities are not found in inactive pockmarks. Interestingly, inactive pockmarks are known to have different macrofaunal communities compared to the surrounding sediments. It is undetermined what the microbial composition of inactive pockmarks is and if it shows a similar pattern as the macrofauna. The Norwegian Oslofjord contains many inactive pockmarks and they are well suited to study the influence of these geological features on the microbial community in the sediment. Here we present a detailed analysis of the microbial communities found in three inactive pockmarks and two control samples at two core depth intervals. The communities were analyzed using high-throughput amplicon sequencing of the 16S rRNA V3 region. Microbial communities of surface pockmark sediments were indistinguishable from communities found in the surrounding seabed. In contrast, pockmark communities at 40 cm sediment depth had a significantly different community structure from normal sediments at the same depth. Statistical analysis of chemical variables indicated significant differences in the concentrations of total carbon and non-particulate organic carbon between 40 cm pockmarks and reference sample sediments. We discuss these results in comparison with the taxonomic classification of the OTUs identified in our samples. Our results indicate that microbial communities at the sediment surface are affected by the water column, while the deeper (40 cm sediment communities are affected by local conditions within the sediment.

Geologic map and cross sections of the Embudo Fault Zone in the Southern Taos Valley, Taos County, New Mexico

Science.gov (United States)

Bauer, Paul W.; Kelson, Keith I.; Grauch, V.J.S.; Drenth, Benjamin J.; Johnson, Peggy S.; Aby, Scott B.; Felix, Brigitte

2016-01-01

The southern Taos Valley encompasses the physiographic and geologic transition zone between the Picuris Mountains and the San Luis Basin of the Rio Grande rift. The Embudo fault zone is the rift transfer structure that has accommodated the kinematic disparities between the San Luis Basin and the Española Basin during Neogene rift extension. The eastern terminus of the transfer zone coincides with the intersection of four major fault zones (Embudo, Sangre de Cristo, Los Cordovas, and Picuris-Pecos), resulting in an area of extreme geologic and hydrogeologic complexities in both the basin-fill deposits and the bedrock. Although sections of the Embudo fault zone are locally exposed in the bedrock of the Picuris Mountains and in the late Cenozoic sedimentary units along the top of the Picuris piedmont, the full proportions of the fault zone have remained elusive due to a pervasive cover of Quaternary surficial deposits. We combined insights derived from the latest geologic mapping of the area with deep borehole data and high-resolution aeromagnetic and gravity models to develop a detailed stratigraphic/structural model of the rift basin in the southern Taos Valley area. The four fault systems in the study area overlap in various ways in time and space. Our geologic model states that the Picuris-Pecos fault system exists in the basement rocks (Picuris formation and older units) of the rift, where it is progressively down dropped and offset to the west by each Embudo fault strand between the Picuris Mountains and the Rio Pueblo de Taos. In this model, the Miranda graben exists in the subsurface as a series of offset basement blocks between the Ponce de Leon neighborhood and the Rio Pueblo de Taos. In the study area, the Embudo faults are pervasive structures between the Picuris Mountains and the Rio Pueblo de Taos, affecting all geologic units that are older than the Quaternary surficial deposits. The Los Cordovas faults are thought to represent the late Tertiary to

Geology of Muntok area and the potency of menumbang granite as source of Uranium and Thorium

International Nuclear Information System (INIS)

Kurniawan Dwi Saksama; Ngadenin

2013-01-01

In the West Bangka there are some granites namely Menumbing, Pelangas, Tempilang, and Jebus granite. The granites is granite tin belt that stretches from Thailand-Malaysia-Bangka Belitung. Granite tin belt or granite source of tin (cassiterite) can act as a source of U and Th. Aims of the study is to find out the information on the geology of Muntok area and its surrounding and to determine the potency of Menumbing granite as a source of U and Th. The methods used is surface geological mapping in Muntok areas and its surrounding with scale 1 : 25.000, measurement grade of uranium and thorium in Menumbing granite areas and petrographic and grain size analysis of sample of Menumbing granite. Determination of granites a source of U and Th is based on content of radioactive mineral, anomaly of U and Th, megascopic and microscopic observation of granite. Morphology of Muntok areas and its surrounding is denudasional undulating plains to hills with an elevation ranging from 0 to 455 meters. Stratigraphy of research areas from old to young is meta sandstone units, granite intrusion of Menumbing and alluvial. Evolving fault is a fault trending West-East. Based on the presence of radioactive minerals, grade of U and Th as well as the type of granite, it was concluded that the Menumbing granite is a source of Th and not sources of U. (author)

Glacial sequence stratigraphy reveal the Weichselian glacial history of the SE sector of the Eurasian Ice Sheet

Science.gov (United States)

Räsänen, Matti

2016-04-01

Reconstructions of the last Weichselian glacial cycle 117,000-11,700 years (kyr) ago propose that S Finland, adjacent Russia and the Baltic countries in the SE sector of the Eurasian Ice Sheet (EIS), were glaciated during the Middle Weichselian time [marine isotope stage (MIS) 4, 71-57 kyr ago] and that this glaciation was preceded in S Finland by an Early Weichselian interstadial (MIS 5c, 105-93 kyr ago) with pine forest. Here glacial sequence stratigraphy (Powell and Cooper 2002) is applied to isolated Late Pleistocene onshore outcrop sections in S Finland. The analysed sedimentary records have traditionally been investigated, interpreted and published separately by different authors without an attempt to a methodologically more systematic survey. By putting new field data and old observations into a regional sequence stratigraphic framework it is shown how previously unnoticed regularities can be found in the lithofacies and fossil successions. It is shown that the proposed Middle Weichselian glaciation or the pine dominated interstadial did not take place at all (Räsänen et al. 2015). The one Late Weichselian glaciation (MIS 2, 29-11 kyr ago) at the SE sector of EIS was preceded in S Finland by a nearly 90 kyr long still poorly known non-glacial period, featuring tundra with permafrost and probably birch forest. The new Middle Weichselian paleoenvironmental scenario revises the configuration and hydrology of the S part of EIS and gives new setting for the evolution of Scandinavian biota. References Powell, R. D., and Cooper, J. M., 2002, A glacial sequence stratigraphic model for temperate, glaciated continental shelves, in Dowdeswell, J. A., and Cofaig, C. Ó. eds., Glacier-Influenced Sedimentation on High-Latitude Continental Margins: The Geological Society of London, London, Geological Society London, Special Publication v. 203, p. 215-244. Räsänen, M.E., Huitti, J.V., Bhattarai, S. Harvey, J. and Huttunen, S. 2015, The SE sector of the Middle

The stratigraphy and evolution of lower Mount Sharp from spectral, morphological, and thermophysical orbital data sets.

Science.gov (United States)

Fraeman, A A; Ehlmann, B L; Arvidson, R E; Edwards, C S; Grotzinger, J P; Milliken, R E; Quinn, D P; Rice, M S

2016-09-01

We have developed a refined geologic map and stratigraphy for lower Mount Sharp using coordinated analyses of new spectral, thermophysical, and morphologic orbital data products. The Mount Sharp group consists of seven relatively planar units delineated by differences in texture, mineralogy, and thermophysical properties. These units are (1-3) three spatially adjacent units in the Murray formation which contain a variety of secondary phases and are distinguishable by thermal inertia and albedo differences, (4) a phyllosilicate-bearing unit, (5) a hematite-capped ridge unit, (6) a unit associated with material having a strongly sloped spectral signature at visible near-infrared wavelengths, and (7) a layered sulfate unit. The Siccar Point group consists of the Stimson formation and two additional units that unconformably overlie the Mount Sharp group. All Siccar Point group units are distinguished by higher thermal inertia values and record a period of substantial deposition and exhumation that followed the deposition and exhumation of the Mount Sharp group. Several spatially extensive silica deposits associated with veins and fractures show that late-stage silica enrichment within lower Mount Sharp was pervasive. At least two laterally extensive hematitic deposits are present at different stratigraphic intervals, and both are geometrically conformable with lower Mount Sharp strata. The occurrence of hematite at multiple stratigraphic horizons suggests redox interfaces were widespread in space and/or in time, and future measurements by the Mars Science Laboratory Curiosity rover will provide further insights into the depositional settings of these and other mineral phases.

A 3D visualization of spatial relationship between geological structure and groundwater chemical profile around Iwate volcano, Japan: based on the ARCGIS 3D Analyst

Science.gov (United States)

Shibahara, A.; Ohwada, M.; Itoh, J.; Kazahaya, K.; Tsukamoto, H.; Takahashi, M.; Morikawa, N.; Takahashi, H.; Yasuhara, M.; Inamura, A.; Oyama, Y.

2009-12-01

We established 3D geological and hydrological model around Iwate volcano to visualize 3D relationships between subsurface structure and groundwater profile. Iwate volcano is a typical polygenetic volcano located in NE Japan, and its body is composed of two stratovolcanoes which have experienced sector collapses several times. Because of this complex structure, groundwater flow around Iwate volcano is strongly restricted by subsurface construction. For example, Kazahaya and Yasuhara (1999) clarified that shallow groundwater in north and east flanks of Iwate volcano are recharged at the mountaintop, and these flow systems are restricted in north and east area because of the structure of younger volcanic body collapse. In addition, Ohwada et al. (2006) found that these shallow groundwater in north and east flanks have relatively high concentration of major chemical components and high 3He/4He ratios. In this study, we succeeded to visualize the spatial relationship between subsurface structure and chemical profile of shallow and deep groundwater system using 3D model on the GIS. In the study region, a number of geological and hydrological datasets, such as boring log data and groundwater chemical profile, were reported. All these paper data are digitized and converted to meshed data on the GIS, and plotted in the three dimensional space to visualize spatial distribution. We also inputted digital elevation model (DEM) around Iwate volcano issued by the Geographical Survey Institute of Japan, and digital geological maps issued by Geological Survey of Japan, AIST. All 3D models are converted into VRML format, and can be used as a versatile dataset on personal computer.

High-resolution sequence stratigraphy and its controls on uranium mineralization. Taking middle Jurassic Qingtujing formation in Chaoshui basin as an example

International Nuclear Information System (INIS)

Yao Chunling; Guo Qingyin; Chen Zuyi; Liu Hongxu

2006-01-01

By applying the high-resolution sequence stratigraphy, the different sub-divisions of base-level cycles of Qingtujing Formation, Middle Jurassic in Chaoshui Basin are analyzed in detail. 23 short, 3 middle and 1 long base-level cycles are recognized. On the above basis, the corresponding frameworks of high-resolution sequence stratigraphy have been established in northern and southern sub-basins respectively, and the detailed sedimentary facies of MSC 1-3 and the special distribution of Qintujing Formation are discussed. It is pointed out that MSC 2 is the most favorable layer for the localization of sandstone-type uranium deposits. (authors)

Scientific basis to assess the potential for geological sequestration of CO{sub 2} in Switzerland

Energy Technology Data Exchange (ETDEWEB)

Diamond, L. W.; Chevalier, G. [Institut fuer Geologie, Universitaet Bern, Bern (Switzerland); Leu, W. [Geoform AG, Geologische Beratungen und Studien, Villeneuve (former Minusio) (Switzerland)

2010-07-01

Possibilities to sequester anthropogenic CO{sub 2} in deep geological formations are being investigated worldwide, but the potential within Switzerland has not yet been evaluated. This study presents a first-order appraisal based solely on geological criteria collated from the literature. The Swiss Molasse Basin (SMB) and the adjacent Folded Jura are the only realms of the country where CO{sub 2} could conceivably be stored in saline aquifers. Evaluation of geological criteria at the basin-wide scale shows that the SMB-Jura has moderate potential (score of 0.6 on a scale from 0 to 1) when compared to basins elsewhere. At the intrabasinal scale, inspection of the stratigraphy reveals four regional candidate aquifers that are sealed by suitable caprocks: top Basement plus basal Mesozoic sandstones, all sealed by the Anhydrite Group; Upper Muschelkalk sealed by the Gipskeuper; Hauptrogenstein sealed by the Effinger Member, and Upper Malm plus Lower Cretaceous sealed by the Lower Freshwater Molasse. Nine geological criteria are defined to evaluate the storage potential of these and other smaller-scale candidates. A numerical scoring and weighting scheme allows the criteria to be assessed simultaneously, permitting the storage potential to be depicted using the 0-1 scale in contoured maps. Approximately 5000 km{sup 2} of the central SMB exhibits potentials between 0.6 and 0.96. The Fribourg-Olten-Lucerne area is the most favoured owing to the presence of several sealed aquifers within the preferred 800-2500 m depth interval, and to its low seismicity, low geothermal gradient, low fault density, and long groundwater residence times. Smaller areas with good potential lie between Zurich and St. Gall. In contrast, western Switzerland, the Jura and the southern SMB have markedly poorer potential. Considering only the portions of the aquifers with potential above 0.6, the theoretical, effective storage capacity of the basin is estimated to be 2680 million tonnes of CO{sub 2

How Students and Field Geologists Reason in Integrating Spatial Observations from Outcrops to Visualize a 3-D Geological Structure

Science.gov (United States)

Kastens, Kim A.; Agrawal, Shruti; Liben, Lynn S.

2009-01-01

Geologists and undergraduate students observed eight artificial "rock outcrops" in a realistically scaled field area, and then tried to envision a geological structure that might plausibly be formed by the layered rocks in the set of outcrops. Students were videotaped as they selected which of fourteen 3-D models they thought best…