A new groundwater radiocarbon correction approach accounting for palaeoclimate conditions during recharge and hydrochemical evolution: The Ledo-Paniselian Aquifer, Belgium

Energy Technology Data Exchange (ETDEWEB)

Blaser, P.C., E-mail: petra.blaser@petraconsult.com [Petraconsult buero fuer angewandte geologie dipl. geol. petra c. blaser, Bergstrasse 269, CH 8707 Uetikon am See (Switzerland); Coetsiers, M. [Laboratory for Applied Geology and Hydrogeology, Ghent University, B-9000 Ghent (Belgium); Aeschbach-Hertig, W. [Institut fuer Umweltphysik, Universitaet Heidelberg, D-69120 Heidelberg (Germany); Kipfer, R. [Department of Water Resources and Drinking Water, Eawag, Swiss Federal Institute of Aquatic Science and Technology, CH-8600 Duebendorf (Switzerland)] [Institute of Isotope Geochemistry and Mineral Resources, ETH Zurich, CH-8092 Zurich (Switzerland); Van Camp, M. [Laboratory for Applied Geology and Hydrogeology, Ghent University, B-9000 Ghent (Belgium); Loosli, H.H. [Department of Climate and Environmental Physics, University of Bern, CH 3012 Bern (Switzerland); Walraevens, K. [Laboratory for Applied Geology and Hydrogeology, Ghent University, B-9000 Ghent (Belgium)

2010-03-15

The particular objective of the present work is the development of a new radiocarbon correction approach accounting for palaeoclimate conditions at recharge and hydrochemical evolution. Relevant climate conditions at recharge are atmospheric pCO{sub 2} and infiltration temperatures, influencing C isotope concentrations in recharge waters. The new method is applied to the Ledo-Paniselian Aquifer in Belgium. This is a typical freshening aquifer where recharge takes place through the semi-confining cover of the Bartonian Clay. Besides cation exchange which is the major influencing process for the evolution of groundwater chemistry (particularly in the Bartonian Clay), also mixing with the original porewater solution (fossil seawater) occurs in the aquifer. Recharge temperatures were based on noble gas measurements. Potential infiltration water compositions, for a range of possible pCO{sub 2}, temperature and calcite dissolution system conditions, were calculated by means of PHREEQC. Then the sampled groundwaters were modelled starting from these infiltration waters, using the computer code NETPATH and considering a wide range of geochemical processes. Fitting models were selected on the basis of correspondence of calculated {delta}{sup 13}C with measured {delta}{sup 13}C. The {sup 14}C modelling resulted in residence times ranging from Holocene to Pleistocene (few hundred years to over 40 ka) and yielded consistent results within the uncertainty estimation. Comparison was made with the {delta}{sup 13}C and Fontes and Garnier correction models, that do not take climate conditions at recharge into account. To date these are considered as the most representative process-oriented existing models, yet differences in calculated residence times of mostly several thousands of years (up to 19 ka) are revealed with the newly calculated ages being mostly (though not always) younger. Not accounting for climate conditions at recharge (pCO{sub 2} and temperature) is thus producing

The use of perturbed physics ensembles and emulation in palaeoclimate reconstruction (Invited)

Science.gov (United States)

Edwards, T. L.; Rougier, J.; Collins, M.

2010-12-01

Climate is a coherent process, with correlations and dependencies across space, time, and climate variables. However, reconstructions of palaeoclimate traditionally consider individual pieces of information independently, rather than making use of this covariance structure. Such reconstructions are at risk of being unphysical or at least implausible. Climate simulators such as General Circulation Models (GCMs), on the other hand, contain climate system theory in the form of dynamical equations describing physical processes, but are imperfect and computationally expensive. These two datasets - pointwise palaeoclimate reconstructions and climate simulator evaluations - contain complementary information, and a statistical synthesis can produce a palaeoclimate reconstruction that combines them while not ignoring their limitations. We use an ensemble of simulators with perturbed parameterisations, to capture the uncertainty about the simulator variant, and our method also accounts for structural uncertainty. The resulting reconstruction contains a full expression of climate uncertainty, not just pointwise but also jointly over locations. Such joint information is crucial in determining spatially extensive features such as isotherms, or the location of the tree-line. A second outcome of the statistical analysis is a refined distribution for the simulator parameters. In this way, information from palaeoclimate observations can be used directly in quantifying uncertainty in future climate projections. The main challenge is the expense of running a large scale climate simulator: each evaluation of an atmosphere-ocean GCM takes several months of computing time. The solution is to interpret the ensemble of evaluations within an 'emulator', which is a statistical model of the simulator. This technique has been used fruitfully in the statistical field of Computer Models for two decades, and has recently been applied in estimating uncertainty in future climate predictions in the

Predictability of the evolution of hydrogeological and hydrogeochemical systems; geological disposal of nuclear waste in crystalline rocks

International Nuclear Information System (INIS)

Murphy, W.M.; Diodato, D.M.

2009-01-01

Confidence in long-term geologic isolation of high-level nuclear waste and spent nuclear fuel requires confidence in predictions of the evolution of hydrogeological and hydrogeochemical systems. Prediction of the evolution of hydrogeological and hydrogeochemical systems is based on scientific understanding of those systems in the present - an understanding that can be tested with data from the past. Crystalline rock settings that have been geologically stable for millions of years and longer offer the potential of predictable, long-term waste isolation. Confidence in predictions of geologic isolation of radioactive waste can measured by evaluating the extent to which those predictions and their underlying analyses are consistent with multiple independent lines of evidence identified in the geologic system being analysed, as well as with evidence identified in analogs to that geologic system. The proposed nuclear waste repository at Yucca Mountain, Nevada, United States, differs in significant ways from potential repository sites being considered by other nations. Nonetheless, observations of hydrogeological and hydrogeochemical systems of Yucca Mountain and Yucca Mountain analogs present multiple independent lines of evidence that can be used in evaluating long-term predictions of the evolution of hydrogeological and hydrogeochemical systems at Yucca Mountain. (authors)

Geological and rock mechanics aspects of the long-term evolution of a crystalline rock site

International Nuclear Information System (INIS)

Cosgrove, J.W.; Hudson, J.A.

2009-01-01

We consider the stability of a crystalline rock mass and hence the integrity of a radioactive waste repository contained therein by, firstly, identifying the geological evolution of such a site and, secondly, by assessing the likely rock mechanics consequences of the natural perturbations to the repository. In this way, the potency of an integrated geological-rock mechanics approach is demonstrated. The factors considered are the pre-repository geological evolution, the period of repository excavation, emplacement and closure, and the subsequent degradation and natural geological perturbations introduced by glacial loading. It is found that the additional rock stresses associated with glacial advance and retreat have a first order effect on the stress magnitudes and are likely to cause a radical change in the stress regime. There are many factors involved in the related geosphere stability and so the paper concludes with a systems diagram of the total evolutionary considerations before, during and after repository construction. (authors)

Incorporating palaeoclimate data into water security planning and decision making - a case study from southeast Queensland, Australia

Science.gov (United States)

Kiem, Anthony; Vance, Tessa; Tozer, Carly; Roberts, Jason

2017-04-01

Decision makers in the water sector need to deal with existing hydroclimatic variability and uncertainty about future changes to climate and catchment conditions. Identifying solutions for hydroclimatic risk adaptation strategies that are both optimal and robust in the presence of variability and uncertainty presents a difficult challenge. A major reason for this challenge is the fact that the instrumental record in Australia is short ( 60-130 years) and fails to encompass enough climate variability to allow the calculation of robust statistics around the baseline risk of extreme events (e.g. multi-year droughts, decadal periods with clustering of major flood events). This climate variability is documented pre-1900 in palaeoclimate records from sources such as corals, tree-rings, freshwater and marine sediments. Despite being remote from Queensland, a high resolution and highly correlated palaeoclimate record from the Law Dome ice cores in Antarctica (Vance et al. 2015) is also now available and has identified eight mega-droughts (lasting from 5-39 years) during 1000-2009 AD. Most importantly, the palaeoclimate information confirms that the post-1900 instrumental period (i.e. the period on which all water resources infrastructure, policy, operation rules and strategies is based) does not capture the full range of variability that has occurred. Other work also clearly shows that, out to 2050 at least, impacts associated with natural variability significantly exceed even the worst-case climate change scenarios (i.e. obtained from Global Climate Models run under the highest emission scenarios). This presentation will demonstrate how the Law Dome ice cores from Antarctica have been used to produce a highly accurate, 1000 year, annual and seasonal resolution, hydroclimate reconstruction (i.e. precipitation and streamflow) for the southeast Queensland region of Australia. We will then show how the palaeoclimate data has been incorporated into the South East Queensland

Are there pre-Quaternary geological analogues for a future greenhouse warming?

Science.gov (United States)

Haywood, A.M.; Ridgwell, A.; Lunt, D.J.; Hill, D.J.; Pound, M.J.; Dowsett, H.J.; Dolan, A.M.; Francis, J.E.; Williams, M.

2011-01-01

Given the inherent uncertainties in predicting how climate and environments will respond to anthropogenic emissions of greenhouse gases, it would be beneficial to society if science could identify geological analogues to the human race's current grand climate experiment. This has been a focus of the geological and palaeoclimate communities over the last 30 years, with many scientific papers claiming that intervals in Earth history can be used as an analogue for future climate change. Using a coupled ocean-atmosphere modelling approach, we test this assertion for the most probable pre-Quaternary candidates of the last 100 million years: the Mid- and Late Cretaceous, the Palaeocene-Eocene Thermal Maximum (PETM), the Early Eocene, as well as warm intervals within the Miocene and Pliocene epochs. These intervals fail as true direct analogues since they either represent equilibrium climate states to a long-term CO2 forcing-whereas anthropogenic emissions of greenhouse gases provide a progressive (transient) forcing on climate-or the sensitivity of the climate system itself to CO2 was different. While no close geological analogue exists, past warm intervals in Earth history provide a unique opportunity to investigate processes that operated during warm (high CO2) climate states. Palaeoclimate and environmental reconstruction/modelling are facilitating the assessment and calculation of the response of global temperatures to increasing CO2 concentrations in the longer term (multiple centuries); this is now referred to as the Earth System Sensitivity, which is critical in identifying CO2 thresholds in the atmosphere that must not be crossed to avoid dangerous levels of climate change in the long term. Palaeoclimatology also provides a unique and independent way to evaluate the qualities of climate and Earth system models used to predict future climate. ?? 2011 The Royal Society.

Geologic evolution of Tucurui region - Para

International Nuclear Information System (INIS)

Silva Matta, M.A. da.

1982-01-01

The northern part of the Araguaia Belt is exposed in the Tucurui region and their stratigraphic, structural, metamorphic and magmatic features had been studied aiming at contributing for the understanding of the geological evolution of the area. Dating with R-Sr and K-At are also presented, allowing some association for the lythotype of Xingu complex and Araguaia Belt. The oldest stratigraphic unit of the area is represented by the Xingu Complex, composed by gneisses and granites and subordinated schists and anphibolites. Over this unit, during the niddle Proterozoic, the Tucurui group was developed. The bottom of this unit is composed by a sequence of tholeiitic basaltic flows which were here enclosed in the Caripe Formation. The Morrote Formation, is made up of graywackes, and constitutes the upper part of the Tucurui Group. The geossinolinal evolution of the Araguaia Belt took place during the Uruacuano Cycle. This geoteotonic unit is represented in the studied area by the Couto Magalhaes Formation (Tocantins Group) which comprises pelitic and psamitic metasediments. After the metamorphism of the Araguaia Belt, the Couto Magalhaes Formation acted as the place of mafic and ultramafic intrusion and, lately, the Tucurui Fault thrusted the metamorphic rocks of the Tocantins Group over the Tucurui Group lithetypes. (author)

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

Evolution of waste-package design at the potential U.S. geologic repository

International Nuclear Information System (INIS)

Benton, H.; Harkins, B.

2000-01-01

This paper describes the evolution of the waste-package design at the potential geologic repository for spent nuclear fuel and high-level waste at Yucca Mountain in Nevada. Because the potential repository is the first of its kind, the design of its components must be flexible and capable of evolving in response to continuing scientific study, development efforts, and changes to performance criteria. The team of scientists and engineers at the Yucca Mountain Project has utilized a systematic, scientific approach to design the potential geologic nuclear-waste repository. As a result of continuing development efforts, the design has incorporated a growing base of scientific and engineering information to ensure that regulatory and performance requirements are met. (authors)

Low-resolution Australasian palaeoclimate records of the last 2000 years

Science.gov (United States)

Dixon, Bronwyn C.; Tyler, Jonathan J.; Lorrey, Andrew M.; Goodwin, Ian D.; Gergis, Joëlle; Drysdale, Russell N.

2017-10-01

Non-annually resolved palaeoclimate records in the Australasian region were compiled to facilitate investigations of decadal to centennial climate variability over the past 2000 years. A total of 675 lake and wetland, geomorphic, marine, and speleothem records were identified. The majority of records are located near population centres in southeast Australia, in New Zealand, and across the maritime continent, and there are few records from the arid regions of central and western Australia. Each record was assessed against a set of a priori criteria based on temporal resolution, record length, dating methods, and confidence in the proxy-climate relationship over the Common Era. A subset of 22 records met the criteria and were endorsed for subsequent analyses. Chronological uncertainty was the primary reason why records did not meet the selection criteria. New chronologies based on Bayesian techniques were constructed for the high-quality subset to ensure a consistent approach to age modelling and quantification of age uncertainties. The primary reasons for differences between published and reconstructed age-depth models were the consideration of the non-singular distribution of ages in calibrated 14C dates and the use of estimated autocorrelation between sampled depths as a constraint for changes in accumulation rate. Existing proxies and reconstruction techniques that successfully capture climate variability in the region show potential to address spatial gaps and expand the range of climate variables covering the last 2000 years in the Australasian region. Future palaeoclimate research and records in Australasia could be greatly improved through three main actions: (i) greater data availability through the public archiving of published records; (ii) thorough characterisation of proxy-climate relationships through site monitoring and climate sensitivity tests; and (iii) improvement of chronologies through core-top dating, inclusion of tephra layers where possible

Time evolution of the Clay Barrier Chemistry in a HLW deep geological disposal in granite

International Nuclear Information System (INIS)

Font, I.; Miguel, M. J.; Juncosa, R.

2000-01-01

The main goal of a high level waste geological disposal is to guarantee the waste isolation from the biosphere, locking them away into very deep geological formations. The best way to assure the isolation is by means of a multiple barrier system. These barriers, in a serial disposition, should assure the confinement function of the disposal system. Two kinds of barriers are considered: natural barriers (geological formations) and engineered barriers (waste form, container and backfilling and sealing materials). Bentonite is selected as backfilling and sealing materials for HLW disposal into granite formations, due to its very low permeability and its ability to fill the remaining spaces. bentonite has also other interesting properties, such as, the radionuclide retention capacity by sorption processes. Once the clay barrier has been placed, the saturation process starts. The granite groundwater fills up the voids of the bentonite and because of the chemical interactions, the groundwater chemical composition varies. Near field processes, such as canister corrosion, waste leaching and radionuclide release, strongly depends on the water chemical composition. Bentonite pore water composition is such a very important feature of the disposal system and its determination and its evolution have great relevance in the HLW deep geological disposal performance assessment. The process used for the determination of the clay barrier pore water chemistry temporal evolution, and its influence on the performance assessment, are presented in this paper. (Author)

Spectra of Earth-like Planets through Geological Evolution around FGKM Stars

Science.gov (United States)

Rugheimer, S.; Kaltenegger, L.

2018-02-01

Future observations of terrestrial exoplanet atmospheres will occur for planets at different stages of geological evolution. We expect to observe a wide variety of atmospheres and planets with alternative evolutionary paths, with some planets resembling Earth at different epochs. For an Earth-like atmospheric time trajectory, we simulate planets from the prebiotic to the current atmosphere based on geological data. We use a stellar grid F0V to M8V ({T}{eff}=7000–2400 K) to model four geological epochs of Earth's history corresponding to a prebiotic world (3.9 Ga), the rise of oxygen at 2.0 Ga and at 0.8 Ga, and the modern Earth. We show the VIS–IR spectral features, with a focus on biosignatures through geological time for this grid of Sun-like host stars and the effect of clouds on their spectra. We find that the observability of biosignature gases reduces with increasing cloud cover and increases with planetary age. The observability of the visible O2 feature for lower concentrations will partly depend on clouds, which, while slightly reducing the feature, increase the overall reflectivity, and thus the detectable flux of a planet. The depth of the IR ozone feature contributes substantially to the opacity at lower oxygen concentrations, especially for the high near-UV stellar environments around F stars. Our results are a grid of model spectra for atmospheres representative of Earth's geological history to inform future observations and instrument design and are available online at http://carlsaganinstitute.org/data/.

Palaeoclimate. Chapter 6

Energy Technology Data Exchange (ETDEWEB)

Jansen, E.; Overpeck, J.; Briffa, K.R.; Duplessy, J.C.; Joos, F.; Masson-Delmotte, V.; Olago, D.; Otto-Bliesner, B.; Peltier, W.R.; Rahmstorf, S.; Ramesh, R.; Raynaud, D.; Rind, D.; Solomina, O.; Villalba, R.; Zhang, D.

2007-09-15

This chapter assesses palaeoclimatic data and knowledge of how the climate system changes over interannual to millennial time scales, and how well these variations can be simulated with climate models. Additional palaeoclimatic perspectives are included in other chapters. Palaeoclimate science has made significant advances since the 1970s, when a primary focus was on the origin of the ice ages, the possibility of an imminent future ice age, and the first explorations of the so-called Little Ice Age and Medieval Warm Period. Even in the first IPCC assessment, many climatic variations prior to the instrumental record were not that well known or understood. Fifteen years later, understanding is much improved, more quantitative and better integrated with respect to observations and modelling. After a brief overview of palaeoclimatic methods, including their strengths and weaknesses, this chapter examines the palaeoclimatic record in chronological order, from oldest to youngest. This approach was selected because the climate system varies and changes over all time scales, and it is instructive to understand the contributions that lower-frequency patterns of climate change might make in influencing higher-frequency patterns of variability and change. In addition, an examination of how the climate system has responded to large changes in climate forcing in the past is useful in assessing how the same climate system might respond to the large anticipated forcing changes in the future. Cutting across this chronologically based presentation are assessments of climate forcing and response, and of the ability of state-of-the-art climate models to simulate the responses. Perspectives from palaeoclimatic observations, theory and modelling are integrated wherever possible to reduce uncertainty in the assessment. Several sections also assess the latest developments in the rapidly advancing area of abrupt climate change, that is, forced or unforced climatic change that involves

Palaeoclimate. Chapter 6

International Nuclear Information System (INIS)

Jansen, E.; Overpeck, J.; Briffa, K.R.; Duplessy, J.C.; Joos, F.; Masson-Delmotte, V.; Olago, D.; Otto-Bliesner, B.; Peltier, W.R.; Rahmstorf, S.; Ramesh, R.; Raynaud, D.; Rind, D.; Solomina, O.; Villalba, R.; Zhang, D.

2007-01-01

This chapter assesses palaeoclimatic data and knowledge of how the climate system changes over interannual to millennial time scales, and how well these variations can be simulated with climate models. Additional palaeoclimatic perspectives are included in other chapters. Palaeoclimate science has made significant advances since the 1970s, when a primary focus was on the origin of the ice ages, the possibility of an imminent future ice age, and the first explorations of the so-called Little Ice Age and Medieval Warm Period. Even in the first IPCC assessment, many climatic variations prior to the instrumental record were not that well known or understood. Fifteen years later, understanding is much improved, more quantitative and better integrated with respect to observations and modelling. After a brief overview of palaeoclimatic methods, including their strengths and weaknesses, this chapter examines the palaeoclimatic record in chronological order, from oldest to youngest. This approach was selected because the climate system varies and changes over all time scales, and it is instructive to understand the contributions that lower-frequency patterns of climate change might make in influencing higher-frequency patterns of variability and change. In addition, an examination of how the climate system has responded to large changes in climate forcing in the past is useful in assessing how the same climate system might respond to the large anticipated forcing changes in the future. Cutting across this chronologically based presentation are assessments of climate forcing and response, and of the ability of state-of-the-art climate models to simulate the responses. Perspectives from palaeoclimatic observations, theory and modelling are integrated wherever possible to reduce uncertainty in the assessment. Several sections also assess the latest developments in the rapidly advancing area of abrupt climate change, that is, forced or unforced climatic change that involves

Geological evolution and uranium mineralisation of Chhinjra area, Kulu district, Himachal Pradesh

Energy Technology Data Exchange (ETDEWEB)

Sen, D B; Kumar, Suresh; Gangadharan, G R [Department of Atomic Energy, New Delhi (India). Atomic Minerals Div.

1995-08-01

Several shear-controlled and fracture-filled/disseminated type uranium occurrences are known in the Rampur window. This paper presents the geology and genetic aspects of fracture-filled type of mineralisation in Chhinjra area on the basis of recent stratigraphical, geochronological and tectonic data. Based on the angular unconformity between Manikaran quartzites and overlying chlorite phyllites, the geological evolution of Chhinjra area has been reconstructed in two stages: pre-unconformity and post-unconformity. Each stage is characterised by different phases of deformation with typical structural style and accompanying mineralisation processes. Four major tectonic events can be recognised here, namely 2500 Ma, 1200 Ma, 700 Ma and 55 Ma. Each event has left its imprint on the rocks as well as uranium mineralisation of Chhinjra area. (author). 14 refs., 4 figs.

Micropaleontology and palaeoclimate during the early Cretaceous in the Lishu depression, Songliao basin, Northeast China

Directory of Open Access Journals (Sweden)

Wei Yan

2017-01-01

Full Text Available Diverse and abundant microfossils, such as palynomorphs, algae and Ostracoda, were collected from lower Cretaceous strata of Lishu depression, located in southeastern Songliao basin, and were identified and classified in order to provide relevant, detailed records for paleoclimate research. The early Cretaceous vegetation and climate of southeastern Songliao basin have been inferred from the analysis of palynomorph genera, algae and Ostracoda of the LS1 and SW110 wells. The lower Cretaceous strata include, in ascending stratigraphic order, the Shahezi, Yingcheng and Denglouku formations. Palynological assemblages for each formation, based on biostratigraphic and statistical analyses, provide an assessment of their longitudinal variations. During deposition of the Shahezi Formation, the climate was mid-subtropical. Vegetation consisted of coniferous forest and herbage. During deposition of the Yingcheng Formation, the climate was south Asian tropical. Vegetation consisted mainly of coniferous forest and herbal shrub. In addition, fresh and saline non-marine water dominated the lacustrine setting during deposition of these formations. Deposition of the Denglouku Formation, however, occurred under a hot and dry tropical climate. The vegetation was mostly coniferous forest and lake waters became saline. Palaeoclimate variation is correlated by the lake level change and the development of sedimentary facies. Palaeoclimate contribute to the formation of hydrocarbon source rocks and reservoir.

Tyrannosauroid integument reveals conflicting patterns of gigantism and feather evolution.

Science.gov (United States)

Bell, Phil R; Campione, Nicolás E; Persons, W Scott; Currie, Philip J; Larson, Peter L; Tanke, Darren H; Bakker, Robert T

2017-06-01

Recent evidence for feathers in theropods has led to speculations that the largest tyrannosaurids, including Tyrannosaurus rex , were extensively feathered. We describe fossil integument from Tyrannosaurus and other tyrannosaurids ( Albertosaurus, Daspletosaurus, Gorgosaurus and Tarbosaurus ), confirming that these large-bodied forms possessed scaly, reptilian-like skin. Body size evolution in tyrannosauroids reveals two independent occurrences of gigantism; specifically, the large sizes in Yutyrannus and tyrannosaurids were independently derived. These new findings demonstrate that extensive feather coverings observed in some early tyrannosauroids were lost by the Albian, basal to Tyrannosauridae. This loss is unrelated to palaeoclimate but possibly tied to the evolution of gigantism, although other mechanisms exist. © 2017 The Author(s).

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.

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

Moving beyond the age-depth model paradigm in deep-sea palaeoclimate archives: dual radiocarbon and stable isotope analysis on single foraminifera

Science.gov (United States)

Lougheed, Bryan C.; Metcalfe, Brett; Ninnemann, Ulysses S.; Wacker, Lukas

2018-04-01

Late-glacial palaeoclimate reconstructions from deep-sea sediment archives provide valuable insight into past rapid changes in ocean chemistry. Unfortunately, only a small proportion of the ocean floor with sufficiently high sediment accumulation rate (SAR) is suitable for such reconstructions using the long-standing age-depth model approach. We employ ultra-small radiocarbon (14C) dating on single microscopic foraminifera to demonstrate that the long-standing age-depth model method conceals large age uncertainties caused by post-depositional sediment mixing, meaning that existing studies may underestimate total geochronological error. We find that the age-depth distribution of our 14C-dated single foraminifera is in good agreement with existing bioturbation models only after one takes the possibility of Zoophycos burrowing into account. To overcome the problems associated with the age-depth paradigm, we use the first ever dual 14C and stable isotope (δ18O and δ13C) analysis on single microscopic foraminifera to produce a palaeoclimate time series independent of the age-depth paradigm. This new state of the art essentially decouples single foraminifera from the age-depth paradigm to provide multiple floating, temporal snapshots of ocean chemistry, thus allowing for the successful extraction of temporally accurate palaeoclimate data from low-SAR deep-sea archives. This new method can address large geographical gaps in late-glacial benthic palaeoceanographic reconstructions by opening up vast areas of previously disregarded, low-SAR deep-sea archives to research, which will lead to an improved understanding of the global interaction between oceans and climate.

Moving beyond the age–depth model paradigm in deep-sea palaeoclimate archives: dual radiocarbon and stable isotope analysis on single foraminifera

Directory of Open Access Journals (Sweden)

B. C. Lougheed

2018-04-01

Full Text Available Late-glacial palaeoclimate reconstructions from deep-sea sediment archives provide valuable insight into past rapid changes in ocean chemistry. Unfortunately, only a small proportion of the ocean floor with sufficiently high sediment accumulation rate (SAR is suitable for such reconstructions using the long-standing age–depth model approach. We employ ultra-small radiocarbon (14C dating on single microscopic foraminifera to demonstrate that the long-standing age–depth model method conceals large age uncertainties caused by post-depositional sediment mixing, meaning that existing studies may underestimate total geochronological error. We find that the age–depth distribution of our 14C-dated single foraminifera is in good agreement with existing bioturbation models only after one takes the possibility of Zoophycos burrowing into account. To overcome the problems associated with the age–depth paradigm, we use the first ever dual 14C and stable isotope (δ18O and δ13C analysis on single microscopic foraminifera to produce a palaeoclimate time series independent of the age–depth paradigm. This new state of the art essentially decouples single foraminifera from the age–depth paradigm to provide multiple floating, temporal snapshots of ocean chemistry, thus allowing for the successful extraction of temporally accurate palaeoclimate data from low-SAR deep-sea archives. This new method can address large geographical gaps in late-glacial benthic palaeoceanographic reconstructions by opening up vast areas of previously disregarded, low-SAR deep-sea archives to research, which will lead to an improved understanding of the global interaction between oceans and climate.

Palaeoclimate evolution across the Cretaceous-Palaeogene boundary in the Nanxiong Basin (SE China) recorded by red strata and its correlation with marine records

Science.gov (United States)

Ma, Mingming; Liu, Xiuming; Wang, Wenyan

2018-03-01

The climate during the Cretaceous Period represented one of the greenhouse states of Earth's history. Significant transformation of climate patterns and a mass extinction event characterised by the disappearance of dinosaurs occurred across the Cretaceous-Palaeogene boundary. However, most records of this interval are derived from marine sediments. The continuous and well-exposed red strata of the Nanxiong Basin (SE China) provide ideal material to develop continental records. Considerable research into stratigraphic, palaeontological, chronologic, palaeoclimatic, and tectonic aspects has been carried out for the Datang profile, which is a type section of a non-marine Cretaceous-Palaeogene stratigraphic division in China. For this study, we reviewed previous work and found that (1) the existing chronological framework of the Datang profile is flawed; (2) precise palaeoclimatic reconstruction is lacking because of the limitations of sampling resolution (e.g. carbonate samples) and/or the lack of efficient proxies; and (3) comparisons of climate changes between marine and continental records are lacking. To resolve these problems, detailed field observations and sampling, as well as environmental magnetic and rare earth element (REE) measurements, were carried out. The results show that (1) more accurate ages of the Datang profile range from 72 to 62.8 Ma based on a combination of the most recently published radiometric, palaeontological, and palaeomagnetic ages; (2) there is considerable evidence of palaeosol generation, which indicates that the red strata formed in a long-term hot, oxidising environment that lacked underwater conditions; (3) haematite was the dominant magnetic mineral in the red strata, and the variation trend of magnetic susceptibility was consistent with the oxygen isotope records from deep-sea sediments, which indicates that the content of haematite was controlled by the global climate; and (4) the palaeoclimate changes from 72 to 62.8 Ma in the

Moving beyond the age-depth model paradigm in deep sea palaeoclimate archives: dual radiocarbon and stable isotope analysis on single foraminifera

NARCIS (Netherlands)

Lougheed, Bryan C.; Metcalfe, Brett; Ninnemann, Ulysses S.; Wacker, Lukas

2017-01-01

Late-glacial palaeoclimate reconstructions from deep-sea sediment archives provide valuable insight into past rapid changes in ocean chemistry, but only a small proportion of the ocean floor is suitable for such reconstructions using the existing state-of-the-art using the age-depth approach. We

Pb, Sr and Nd isotope geological characteristics and its evolution of Jianchaling rock

International Nuclear Information System (INIS)

Pang Chunyong; Chen Minyang; Xu Wenxin

2003-01-01

It has been a long time debatable subject on the raw material source and its genesis of Jianchaling ultrabasic rock, because the original rock phases, the original mineral compositions, texture and structure, even part of the chemical components of the rocks had been changed completely after many periods and phases of metamorphism. According to the content of Pb, Rb, Sr, Nd elements and their Pb, Sr, Nd isotope compositions of the rocks, together with the isotope geological age of late magmatic activities, the authors analyze the evolution of Pb, Sr, Nd isotope compositions, The inferred initiate Nd isotope ratio of ultrabasic rocks is 0.510233, lower than that of meteorite unity at a corresponding period, its ε Nd(T)>O; The initiate Sr ratios inferred by the isotope geological age ranges from 0.702735 to 0.719028; Projecting the lead isotope compositions on the Pb tectonic evolution model, the result indicates that the raw material of Jianchaling ultrabasic rock coming from the deplete upper mantle. The ultrabasic magma which enrich of Mg, Ni and less S intruded the crust and formed the Jianchaling ultrabasic rock at late Proterozoic era (927 Ma±). The forming time of serpentinite is mostly equal to the granitoid intruding time, showing the intrusion o flate acidic magma caused a large scale alteration of the ultrabasic rocks and formed the meta-ultrabasic phase rock observed today. (authors)

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

Geology of Uruguay review

International Nuclear Information System (INIS)

Gomez Rifas, C.

2011-01-01

This work is about the Uruguay geology review.This country has been a devoted to breeding cattle and agriculture.The evolution of geological knowledge begun with Dr. Karl Walther who published 53 papers between 1909 and 1948.

Palaeoclimate significance of speleothems in crystalline rocks: a test case from the Late Glacial and early Holocene (Vinschgau, northern Italy)

Science.gov (United States)

Koltai, Gabriella; Cheng, Hai; Spötl, Christoph

2018-03-01

Partly coeval flowstones formed in fractured gneiss and schist were studied to test the palaeoclimate significance of this new type of speleothem archive on a decadal-to-millennial timescale. The samples encompass a few hundred to a few thousand years of the Late Glacial and the early Holocene. The speleothem fabric is primarily comprised of columnar fascicular optic calcite and acicular aragonite, both indicative of elevated Mg / Ca ratios in the groundwater. Stable isotopes suggest that aragonite is more prone to disequilibrium isotope fractionation driven by evaporation and prior calcite/aragonite precipitation than calcite. Changes in mineralogy are therefore attributed to these two internal fracture processes rather than to palaeoclimate. Flowstones formed in the same fracture show similar δ18O changes on centennial scales, which broadly correspond to regional lacustrine δ18O records, suggesting that such speleothems may provide an opportunity to investigate past climate conditions in non-karstic areas. The shortness of overlapping periods in flowstone growth and the complexity of in-aquifer processes, however, render the establishment of a robust stacked δ18O record challenging.

The Interior and Orbital Evolution of Charon as Preserved in Its Geologic Record

Science.gov (United States)

Rhoden, Alyssa Rose; Henning, Wade; Hurford, Terry A.; Hamilton, Douglas P.

2014-01-01

Pluto and its largest satellite, Charon, currently orbit in a mutually synchronous state; both bodies continuously show the same face to one another. This orbital configuration is a natural end-state for bodies that have undergone tidal dissipation. In order to achieve this state, both bodies would have experienced tidal heating and stress, with the extent of tidal activity controlled by the orbital evolution of Pluto and Charon and by the interior structure and rheology of each body. As the secondary, Charon would have experienced a larger tidal response than Pluto, which may have manifested as observable tectonism. Unfortunately, there are few constraints on the interiors of Pluto and Charon. In addition, the pathway by which Charon came to occupy its present orbital state is uncertain. If Charon's orbit experienced a high-eccentricity phase, as suggested by some orbital evolution models, tidal effects would have likely been more significant. Therefore, we determine the conditions under which Charon could have experienced tidally-driven geologic activity and the extent to which upcoming New Horizons spacecraft observations could be used to constrain Charon's internal structure and orbital evolution. Using plausible interior structure models that include an ocean layer, we find that tidally-driven tensile fractures would likely have formed on Charon if its eccentricity were on the order of 0.01, especially if Charon were orbiting closer to Pluto than at present. Such fractures could display a variety of azimuths near the equator and near the poles, with the range of azimuths in a given region dependent on longitude; east-west-trending fractures should dominate at mid-latitudes. The fracture patterns we predict indicate that Charon's surface geology could provide constraints on the thickness and viscosity of Charon's ice shell at the time of fracture formation.

Mineral Grains, Dimples, and Hot Volcanic Organic Streams: Dynamic Geological Backstage of Macromolecular Evolution.

Science.gov (United States)

Skoblikow, Nikolai E; Zimin, Andrei A

2018-04-01

The hypothesis of hot volcanic organic stream as the most probable and geologically plausible environment for abiogenic polycondensation is proposed. The primary synthesis of organic compounds is considered as result of an explosive volcanic (perhaps, meteorite-induced) eruption. The eruption was accompanied by a shock wave propagating in the primeval atmosphere and resulting in the formation of hot cloud of simple organic compounds-aldehydes, alcohols, amines, amino alcohols, nitriles, and amino acids-products, which are usually obtained under the artificial conditions in the spark-discharge experiments. The subsequent cooling of the organic cloud resulted in a gradual condensation and a serial precipitation of organic compounds (in order of decreasing boiling point values) into the liquid phase forming a hot, viscous and muddy organic stream (named "lithorheos"). That stream-even if the time of its existence was short-is considered here as a geologically plausible environment for abiogenic polycondensation. The substances successively prevailing in such a stream were cyanamide, acetamide, formamide, glycolonitrile, acetonitrile. An important role was played by mineral (especially, phosphate-containing) grains (named "lithosomes"), whose surface was modified with heterocyclic nitrogen compounds synthesized in the course of eruption. When such grains got into hot organic streams, their surface catalytic centers (named "lithozymes") played a decisive role in the emergence, facilitation and maintenance of prebiotic reactions and key processes characteristic of living systems. Owing to its cascade structure, the stream was a factor underlying the formation of mineral-polymeric aggregates (named "lithocytes") in the small natural streambed cavities (dimples)-as well as a factor of their further spread within larger geological locations which played a role of chemo-ecological niches. All three main stages of prebiotic evolution (primary organic synthesis

Projected future climate changes in the context of geological and geomorphological hazards.

Science.gov (United States)

Liggins, Felicity; Betts, Richard A; McGuire, Bill

2010-05-28

On palaeoclimate time scales, enhanced levels of geological and geomorphological activity have been linked to climatic factors, including examples of processes that are expected to be important in current and future anthropogenic climate change. Planetary warming leading to increased rainfall, ice-mass loss and rising sea levels is potentially relevant to geospheric responses in many geologically diverse regions. Anthropogenic climate change, therefore, has the potential to alter the risk of geological and geomorphological hazards through the twenty-first century and beyond. Here, we review climate change projections from both global and regional climate models in the context of geohazards. In assessing the potential for geospheric responses to climate change, it appears prudent to consider regional levels of warming of 2 degrees C above average pre-industrial temperature as being potentially unavoidable as an influence on processes requiring a human adaptation response within this century. At the other end of the scale when considering changes that could be avoided by reduction of emissions, scenarios of unmitigated warming exceeding 4 degrees C in the global average include much greater local warming in some regions. However, considerable further work is required to better understand the uncertainties associated with these projections, uncertainties inherent not only in the climate modelling but also in the linkages between climate change and geospheric responses.

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

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.  

Ancient Martian aeolian processes and palaeomorphology reconstructed from the Stimson formation on the lower slope of Aeolis Mons, Gale crater, Mars

OpenAIRE

Banham, Steven G.; Gupta, Sanjeev; Rubin, David M.; Watkins, Jessica A.; Sumner, Dawn Y.; Edgett, Kenneth S.; Grotzinger, John P.; Lewis, Kevin W.; Edgar, Lauren A.; Stack-Morgan, Kathryn M.; Barnes, Robert; Bell, James F., III; Day, Mackenzie D.; Ewing, Ryan C.; Lapotre, Mathieu G. A.

2018-01-01

Reconstruction of the palaeoenvironmental context of Martian sedimentary rocks is central to studies of ancient Martian habitability and regional palaeoclimate history. This paper reports the analysis of a distinct aeolian deposit preserved in Gale crater, Mars, and evaluates its palaeomorphology, the processes responsible for its deposition, and its implications for Gale crater geological history and regional palaeoclimate. Whilst exploring the sedimentary succession cropping out on the nort...

UV SURFACE ENVIRONMENT OF EARTH-LIKE PLANETS ORBITING FGKM STARS THROUGH GEOLOGICAL EVOLUTION

Energy Technology Data Exchange (ETDEWEB)

Rugheimer, S.; Sasselov, D. [Harvard Smithsonian Center for Astrophysics, 60 Garden st., 02138 MA Cambridge (United States); Segura, A. [Instituto de Ciencias Nucleares, Universidad Nacional Autónoma de México, México (Mexico); Kaltenegger, L., E-mail: srugheimer@cfa.harvard.edu [Carl Sagan Institute, Cornell University, Ithaca, NY 14853 (United States)

2015-06-10

The UV environment of a host star affects the photochemistry in the atmosphere, and ultimately the surface UV environment for terrestrial planets and therefore the conditions for the origin and evolution of life. We model the surface UV radiation environment for Earth-sized planets orbiting FGKM stars in the circumstellar Habitable Zone for Earth through its geological evolution. We explore four different types of atmospheres corresponding to an early-Earth atmosphere at 3.9 Gyr ago and three atmospheres covering the rise of oxygen to present-day levels at 2.0 Gyr ago, 0.8 Gyr ago, and modern Earth. In addition to calculating the UV flux on the surface of the planet, we model the biologically effective irradiance, using DNA damage as a proxy for biological damage. We find that a pre-biotic Earth (3.9 Gyr ago) orbiting an F0V star receives 6 times the biologically effective radiation as around the early Sun and 3520 times the modern Earth–Sun levels. A pre-biotic Earth orbiting GJ 581 (M3.5 V) receives 300 times less biologically effective radiation, about 2 times modern Earth–Sun levels. The UV fluxes calculated here provide a grid of model UV environments during the evolution of an Earth-like planet orbiting a range of stars. These models can be used as inputs into photo-biological experiments and for pre-biotic chemistry and early life evolution experiments.

UV SURFACE ENVIRONMENT OF EARTH-LIKE PLANETS ORBITING FGKM STARS THROUGH GEOLOGICAL EVOLUTION

International Nuclear Information System (INIS)

Rugheimer, S.; Sasselov, D.; Segura, A.; Kaltenegger, L.

2015-01-01

The UV environment of a host star affects the photochemistry in the atmosphere, and ultimately the surface UV environment for terrestrial planets and therefore the conditions for the origin and evolution of life. We model the surface UV radiation environment for Earth-sized planets orbiting FGKM stars in the circumstellar Habitable Zone for Earth through its geological evolution. We explore four different types of atmospheres corresponding to an early-Earth atmosphere at 3.9 Gyr ago and three atmospheres covering the rise of oxygen to present-day levels at 2.0 Gyr ago, 0.8 Gyr ago, and modern Earth. In addition to calculating the UV flux on the surface of the planet, we model the biologically effective irradiance, using DNA damage as a proxy for biological damage. We find that a pre-biotic Earth (3.9 Gyr ago) orbiting an F0V star receives 6 times the biologically effective radiation as around the early Sun and 3520 times the modern Earth–Sun levels. A pre-biotic Earth orbiting GJ 581 (M3.5 V) receives 300 times less biologically effective radiation, about 2 times modern Earth–Sun levels. The UV fluxes calculated here provide a grid of model UV environments during the evolution of an Earth-like planet orbiting a range of stars. These models can be used as inputs into photo-biological experiments and for pre-biotic chemistry and early life evolution experiments

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.

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...

Ensemble models on palaeoclimate to predict India's groundwater challenge

Directory of Open Access Journals (Sweden)

Partha Sarathi Datta

2013-09-01

Full Text Available In many parts of the world, freshwater crisis is largely due to increasing water consumption and pollution by rapidly growing population and aspirations for economic development, but, ascribed usually to the climate. However, limited understanding and knowledge gaps in the factors controlling climate and uncertainties in the climate models are unable to assess the probable impacts on water availability in tropical regions. In this context, review of ensemble models on δ18O and δD in rainfall and groundwater, 3H- and 14C- ages of groundwater and 14C- age of lakes sediments helped to reconstruct palaeoclimate and long-term recharge in the North-west India; and predict future groundwater challenge. The annual mean temperature trend indicates both warming/cooling in different parts of India in the past and during 1901–2010. Neither the GCMs (Global Climate Models nor the observational record indicates any significant change/increase in temperature and rainfall over the last century, and climate change during the last 1200 yrs BP. In much of the North-West region, deep groundwater renewal occurred from past humid climate, and shallow groundwater renewal from limited modern recharge over the past decades. To make water management to be more responsive to climate change, the gaps in the science of climate change need to be bridged.

New insight on the paleoproterozoic evolution of the São Francisco Craton: Reinterpretation of the geology, the suture zones and the thicknesses of the crustal blocks using geophysical and geological data

Science.gov (United States)

Sampaio, Edson E. S.; Barbosa, Johildo S. F.; Correa-Gomes, Luiz C.

2017-07-01

The Archean-Paleoproterozoic Jequié (JB) and Itabuna-Salvador-Curaçá (ISCB) blocks and their tectonic transition zone in the Valença region, Bahia, Brazil are potentially important for ore deposits, but the geological knowledge of the area is still meager. The paucity of geological information restricts the knowledge of the position and of the field characteristics of the tectonic suture zone between these two crustal segments JB and ISCB. Therefore, interpretation of geophysical data is necessary to supplement the regional structural and petrological knowledge of the area as well as to assist mining exploration programs. The analysis of the airborne radiometric and magnetic data of the region has established, respectively, five radiometric domains and five magnetic zones. Modeling of a gravity profile has defined the major density contrasts of the deep structures. The integrated interpretation of the geophysical data fitted to the known geological information substantially improved the suture zone (lower plate JB versus upper plate ISCB) delimitation, the geological map of the area and allowed to estimate the thicknesses of these two blocks, and raised key questions about the São Francisco Craton tectonic evolution.

Coquina of the Lagoa Feia formation, Campos Basin: development geology evolution; Coquinas da formacao Lagoa Feia, Bacia de Campos: evolucao da geologia de desenvolvimento

Energy Technology Data Exchange (ETDEWEB)

Baumgarten, Cleyton S; Dultra, Artur J.C.; Silva Scuta, Maximiano da; Figueiredo, Marcus V.L. de; Sequeira, Maria F.P.B. [PETROBRAS, Rio de Janeiro, RJ (Brazil)

1988-01-01

The evolution of Lagoa Feia coquinas is analysed in its several stages, beginning with the exploratory phase. Special emphasis is devoted to the elements which contribute to improvement in geologic mapping. Development of the reservoir geology, interpretation of the factors that had influence in the reservoir pressure, communications between the fields, causing the low pressure, are discussed. The low transmissibility resultant from the heterogeneity created by the calcite and silica cementation are also reported. 11 figs., 7 refs

Advances in planetary geology, volume 2

International Nuclear Information System (INIS)

1986-07-01

This publication is a continuation of volume 1; it is a compilation of reports focusing on research into the origin and evolution of the solar system with emphasis on planetary geology. Specific reports include a multispectral and geomorphic investigation of the surface of Europa and a geologic interpretation of remote sensing data for the Martian volcano Ascreaus Mons

Advances in planetary geology

International Nuclear Information System (INIS)

1987-06-01

The surface of Mars displays a broad range of channel and valley features. There is as great a range in morphology as in scale. Some of the features of Martian geography are examined. Geomorphic mapping, crater counts on selected surfaces, and a detailed study of drainage basins are used to trace the geologic evolution of the Margaritifer Sinus Quandrangle. The layered deposits in the Valles Marineris are described in detail and the geologic processes that could have led to their formation are analyzed

Crosscutting Development- EVA Tools and Geology Sample Acquisition

Science.gov (United States)

2011-01-01

Exploration to all destinations has at one time or another involved the acquisition and return of samples and context data. Gathered at the summit of the highest mountain, the floor of the deepest sea, or the ice of a polar surface, samples and their value (both scientific and symbolic) have been a mainstay of Earthly exploration. In manned spaceflight exploration, the gathering of samples and their contextual information has continued. With the extension of collecting activities to spaceflight destinations comes the need for geology tools and equipment uniquely designed for use by suited crew members in radically different environments from conventional field geology. Beginning with the first Apollo Lunar Surface Extravehicular Activity (EVA), EVA Geology Tools were successfully used to enable the exploration and scientific sample gathering objectives of the lunar crew members. These early designs were a step in the evolution of Field Geology equipment, and the evolution continues today. Contemporary efforts seek to build upon and extend the knowledge gained in not only the Apollo program but a wealth of terrestrial field geology methods and hardware that have continued to evolve since the last lunar surface EVA. This paper is presented with intentional focus on documenting the continuing evolution and growing body of knowledge for both engineering and science team members seeking to further the development of EVA Geology. Recent engineering development and field testing efforts of EVA Geology equipment for surface EVA applications are presented, including the 2010 Desert Research and Technology Studies (Desert RATs) field trial. An executive summary of findings will also be presented, detailing efforts recommended for exotic sample acquisition and pre-return curation development regardless of planetary or microgravity destination.

The need for New In Situ Measurements to Understand the Climate, Geology and Evolution of Venus.

Science.gov (United States)

Grinspoon, D. H.

2017-12-01

Many measurements needed to address outstanding questions about current processes and evolution of Venus can only be made from in situ platforms such as entry probes, balloons or landers. Among these are precise determination of the value and altitude dependence of the deuterium-to-hydrogen ratio, an important tracer of water history which, while clearly greatly elevated compared to the terrestrial ratio, is still unknown within a large range of uncertainty and appears, based on Venus Express results, to display an enigmatic altitude dependence. Rare gas abundances and isotopes provide clues to volatile sources and histories of outgassing and exospheric escape. Modern mass spectrometry at Venus would yield abundances of the eight stable xenon isotopes, bulk abundances of krypton, and isotopes of neon. Altitude profiles of sulfur-containing chemical species would illuminate global geochemical cycles, including cloud formation, outgassing rates and surface-atmosphere interactions. The altitude profile of wind speeds and radiation fluxes, interpreted in light of the Venus Express and Akatsuki data, would enrich understanding of the global circulation and climate dynamics of Venus. Descent and surface images of carefully chosen locations would lend ground truth to interpretations of the near-global Magellan data sets and provide context for global remote sensing data obtained by future orbiter missions. Landed instruments would provide refinement and calibration for chemical abundance measurements by historical missions as well as direct mineralogical measurements of Venusian surface and subsurface rocks. In concert with atmospheric measurements these would greatly constrain geologic history as well as the nature of surface-atmosphere interactions. Such a suite of measurements will deepen our understanding of the origin and evolution of Venus in the context of Solar System and extrasolar terrestrial planets, determine the level and style of current geological activity

Vietnamese sedimentary basins: geological evolution and petroleum potential

Energy Technology Data Exchange (ETDEWEB)

Fyhn, M.B.W.; Petersen, Henrik I.; Mathiesen, A.; Nielsen, Lars H.; Pedersen, Stig A.S.; Lindstroem, S.; Bojesen-Koefoed, J.A.; Abatzis, I.; Boldreel, L.O.

2010-07-15

The Geological Survey of Denmark and Greenland has worked in Vietnam since 1995 to assess the geology and petroleum potential of the Vietnamese basins. Since 2002 the work has been carried out in cooperation with the Department of Geography and Geology, University of Copenhagen, as part of the ENRECA project (Enhancement of Research Capacity in Developing Countries). The ENRECA project has already completed two phases and a third and final phase has recently started. The initial phase focused on the Phu Khanh and the Song Hong Basins located in the South China Sea offshore north and central Vietnam and the smaller onshore Song Ba Trough. During the second ENRECA phase, completed in 2009, attention shifted towards the Malay - Tho Chu and Phu Quoc basins located in the Gulf of Thailand, SSW of Vietnam. The Phu Quoc Basin continues onshore to the north to form part of the mountainous area between Vietnam and Cambodia. In the recently started third phase of the project, the focus remains on the Phu Quoc Basin in addition to a revisit to the Song Hong Basin on the north Vietnamese margin and onshore beneath the Song Hong (Red River) delta. (LN)

Thermochronological constraints on the Cambrian to recent geological evolution of the Argentina passive continental margin

Science.gov (United States)

Kollenz, Sebastian; Glasmacher, Ulrich A.; Rossello, Eduardo A.; Stockli, Daniel F.; Schad, Sabrina; Pereyra, Ricardo E.

2017-10-01

Passive continental margins are geo-archives that store information from the interplay of endogenous and exogenous forces related to continental rifting, post-breakup history, and climate changes. The recent South Atlantic passive continental margins (SAPCMs) in Brazil, Namibia, and South Africa are partly high-elevated margins ( 2000 m a.s.l.), and the recent N-S-trending SAPCM in Argentina and Uruguay is of low elevation. In Argentina, an exception in elevation is arising from the higher topography (> 1000 m a.s.l.) of the two NW-SE-trending mountain ranges Sierras Septentrionales and Sierras Australes. Precambrian metamorphic and intrusive rocks, and siliciclastic rocks of Ordovician to Permian age represent the geological evolution of both areas. The Sierras Australes have been deformed and metamorphosed (incipient - greenschist) during the Gondwanides Orogeny. The low-temperature thermochronological (LTT) data (history of the Gondwanides and the Mesozoic and Cenozoic South Atlantic geological evolution. Upper Carboniferous zircon (U-Th/He)-ages (ZHe) indicate the earliest cooling below 180 °C/1 Ma. Most of the ZHe-ages are of Upper Triassic to Jurassic age. The apatite fission-track ages (AFT) of Sierras Septentrionales and the eastern part of Sierras Australes indicate the South Atlantic rifting and, thereafter. AFT-ages of Middle to Upper Triassic on the western side of the Sierras Australes are in contrast, indicating a Triassic exhumation caused by the eastward thrusting along the Sauce Grande wrench. The corresponding t-T models report a complex subsidence and exhumation history with variable rates since the Ordovician. Based on the LTT-data and the numerical modelling we assume that the NW-SE-trending mountain ranges received their geographic NW-SE orientation during the syn- to post-orogenic history of the Gondwanides.

Wellbore cement fracture evolution at the cement–basalt caprock interface during geologic carbon sequestration

Energy Technology Data Exchange (ETDEWEB)

Jung, Hun Bok; Kabilan, Senthil; Carson, James P.; Kuprat, Andrew P.; Um, Wooyong; Martin, Paul F.; Dahl, Michael E.; Kafentzis, Tyler A.; Varga, Tamas; Stephens, Sean A.; Arey, Bruce W.; Carroll, KC; Bonneville, Alain; Fernandez, Carlos A.

2014-08-07

Composite Portland cement-basalt caprock cores with fractures, as well as neat Portland cement columns, were prepared to understand the geochemical and geomechanical effects on the integrity of wellbores with defects during geologic carbon sequestration. The samples were reacted with CO2-saturated groundwater at 50 ºC and 10 MPa for 3 months under static conditions, while one cement-basalt core was subjected to mechanical stress at 2.7 MPa before the CO2 reaction. Micro-XRD and SEM-EDS data collected along the cement-basalt interface after 3-month reaction with CO2-saturated groundwater indicate that carbonation of cement matrix was extensive with the precipitation of calcite, aragonite, and vaterite, whereas the alteration of basalt caprock was minor. X-ray microtomography (XMT) provided three-dimensional (3-D) visualization of the opening and interconnection of cement fractures due to mechanical stress. Computational fluid dynamics (CFD) modeling further revealed that this stress led to the increase in fluid flow and hence permeability. After the CO2-reaction, XMT images displayed that calcium carbonate precipitation occurred extensively within the fractures in the cement matrix, but only partially along the fracture located at the cement-basalt interface. The 3-D visualization and CFD modeling also showed that the precipitation of calcium carbonate within the cement fractures after the CO2-reaction resulted in the disconnection of cement fractures and permeability decrease. The permeability calculated based on CFD modeling was in agreement with the experimentally determined permeability. This study demonstrates that XMT imaging coupled with CFD modeling represent a powerful tool to visualize and quantify fracture evolution and permeability change in geologic materials and to predict their behavior during geologic carbon sequestration or hydraulic fracturing for shale gas production and enhanced geothermal systems.

Charles Darwin in Australia; or How To Introduce Some Local Colour to the Teaching of Evolution, Geology, Meteorology, and the Determination of Longitude.

Science.gov (United States)

Nicholas, Frank W.

The background to Charles Darwin's little-known visit to Australia, and the account of his experiences while here, provide some invaluable historical material for teaching evolution, geology, meteorology, and the determination of longitude. Indeed, by using his Australian experiences as a foundation, it is possible to explain the theory of…

Proceedings of the 7. Symposium on geology from southeastern Brazil

International Nuclear Information System (INIS)

2001-01-01

This document presents papers on the following subjects: regional geology of the proterozoic and fanerozoic, metallic and non metallic resources, tectoni-sedimentary evolution of the eastern margin Brazil basins and petroleum geology applied to the Santos, Campos and Espirito Santo basins, engineering and environmental geologies, ornamental rocks/building materials/mineral waters/industrial ores

Chirp subbottom profiler data collected in Pamlico Sound on cruise EPamSh-2016 of RV Riggs for the Coastal Hydrodynamics and Natural Geologic Evolution (CHaNGE) project

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Edgetech 216 chirp data (SEG-Y format) collected for the Coastal Hydrodynamics and Natural Geologic Evolution (CHaNGE) project, OCE-1130843. Survey area covers...

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

Evolution of Rosaceae Fruit Types Based on Nuclear Phylogeny in the Context of Geological Times and Genome Duplication.

Science.gov (United States)

Xiang, Yezi; Huang, Chien-Hsun; Hu, Yi; Wen, Jun; Li, Shisheng; Yi, Tingshuang; Chen, Hongyi; Xiang, Jun; Ma, Hong

2017-02-01

Fruits are the defining feature of angiosperms, likely have contributed to angiosperm successes by protecting and dispersing seeds, and provide foods to humans and other animals, with many morphological types and important ecological and agricultural implications. Rosaceae is a family with ∼3000 species and an extraordinary spectrum of distinct fruits, including fleshy peach, apple, and strawberry prized by their consumers, as well as dry achenetum and follicetum with features facilitating seed dispersal, excellent for studying fruit evolution. To address Rosaceae fruit evolution and other questions, we generated 125 new transcriptomic and genomic datasets and identified hundreds of nuclear genes to reconstruct a well-resolved Rosaceae phylogeny with highly supported monophyly of all subfamilies and tribes. Molecular clock analysis revealed an estimated age of ∼101.6 Ma for crown Rosaceae and divergence times of tribes and genera, providing a geological and climate context for fruit evolution. Phylogenomic analysis yielded strong evidence for numerous whole genome duplications (WGDs), supporting the hypothesis that the apple tribe had a WGD and revealing another one shared by fleshy fruit-bearing members of this tribe, with moderate support for WGDs in the peach tribe and other groups. Ancestral character reconstruction for fruit types supports independent origins of fleshy fruits from dry-fruit ancestors, including the evolution of drupes (e.g., peach) and pomes (e.g., apple) from follicetum, and drupetum (raspberry and blackberry) from achenetum. We propose that WGDs and environmental factors, including animals, contributed to the evolution of the many fruits in Rosaceae, which provide a foundation for understanding fruit evolution. © The Author 2016. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

Chirp subbottom profiler data collected in Pamlico Sound on cruise RVRiggs_07_31_2013 of RV Riggs for the Coastal Hydrodynamics and Natural Geologic Evolution (CHaNGE) project

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Edgetech 216 chirp data (SEG-Y format) collected for the Coastal Hydrodynamics and Natural Geologic Evolution (CHaNGE) project, OCE-1130843. Survey area covers...

Chirp subbottom profiler data collected in Pamlico Sound on cruise RVRiggs_07_30_2013 of RV Riggs for the Coastal Hydrodynamics and Natural Geologic Evolution (CHaNGE) project

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Edgetech 216 chirp data (SEG-Y format) collected for the Coastal Hydrodynamics and Natural Geologic Evolution (CHaNGE) project, OCE-1130843. Survey area covers...

Geological investigations for geological model of deep underground geoenvironment at the Mizunami Underground Research Laboratory (MIU)

International Nuclear Information System (INIS)

Tsuruta, Tadahiko; Tagami, Masahiko; Amano, Kenji; Matsuoka, Toshiyuki; Kurihara, Arata; Yamada, Yasuhiro; Koike, Katsuaki

2013-01-01

Japan Atomic Energy Agency (JAEA) is performing a geoscientific research project, the Mizunami Underground Research Laboratory (MIU) project, in order to establish scientific and technological basis for geological disposal of high-level radioactive wastes. The MIU is located in crystalline rock environment, in Mizunami City, central Japan. Field investigations include geological mapping, reflection seismic surveys, several borehole investigations and geological investigations in the research galleries to identify the distribution and heterogeneity of fractures and faults that are potential major flowpaths for groundwater. The results of these field investigations are synthesized and compiled for the purpose of geological modeling. The field investigations indicate that the Main Shaft at the MIU intersected low permeability NNW oriented faults. A high permeability fracture zone in the granite, a significant water inflow point, was observed in the Ventilation Shaft. Development of the geological model focusing 3D spatial relationships at different scales and evolution of the geoenvironment are underway. This paper describes geological investigations applied in the MIU project, focusing on the evaluation of their effectiveness to understand for deep underground geoenvironment. (author)

Chirp subbottom profiler data collected in Pamlico Sound on cruise RVRiggs_05_23_24_2012 of RV Riggs for the Coastal Hydrodynamics and Natural Geologic Evolution (CHaNGE) project

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Edgetech 216 chirp data (SEG-Y format) collected for the Coastal Hydrodynamics and Natural Geologic Evolution (CHaNGE) project, OCE-1130843. Survey area covers...

Deglacial palaeoclimate at Puerto del Hambre, subantarctic Patagonia, Chile

Science.gov (United States)

Heusser, Calvin J.; Heusser, Linda E.; Lowell, Thomas V.; Moreira M., Andrés; Moreira M., Simón

2000-02-01

The primary objective of this study is to further substantiate multistep climatic forcing of late-glacial vegetation in southern South America. A secondary objective is to establish the age of deglaciation in Estrecho de Magallanes-Bahía Inútil. Pollen assemblages at 2-cm intervals in a core of the mire at Puerto del Hambre (53°3621S, 70°5553W) provide the basis for reconstructing the vegetation and a detailed account of palaeoclimate in subantarctic Patagonia. Chronology over the 262-cm length of core is regulated by 20 AMS radiocarbon dates between 14 455 and 10 089 14C yr BP. Of 13 pollen assemblage zones, the earliest representing the Oldest Dryas chronozone (14 455-13 000 14C yr BP) records impoverished steppe with decreasing frequencies and loss of southern beech (Nothofagus). Successive 100-yr-long episodes of grass/herbs and of heath (Empetrum/Ericaceae) before 14 000 14C yr BP infer deglacial successional communities under a climate of increased continentality prior to the establishment of grass-dominated steppe. The Bølling-Allerød (13 000-11 000 14C yr BP) is characterised by mesic grassland under moderating climate that with abrupt change to heath dominance after 12 000 14C yr BP was warmer and not as humid. At the time of the Younger Dryas (11 000-10 000 14C yr BP), grass steppe expanded with a return of colder, more humid climate. Later, with gradual warming, communities were invaded by southern beech. The Puerto del Hambre record parallels multistep, deglacial palaeoclimatic sequences reported elsewhere in the Southern Andes and at Taylor Dome in Antarctica. Deglaciation of Estrecho de Magallanes-Bahía Inútil is dated close to 14 455 14C yr BP, invalidating earlier dates of between 15 800 and 16 590 14C yr BP.

Chirp subbottom profiler data collected in Pamlico Sound on cruise RVRiggs_05_20_22_2014 of RV Riggs for the Coastal Hydrodynamics and Natural Geologic Evolution (CHaNGE) project

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Edgetech 216 chirp data (SEG-Y format) collected for the Coastal Hydrodynamics and Natural Geologic Evolution (CHaNGE) project, OCE-1130843. Survey area covers the...

Formation and Evolution of Lakshmi Planum (V-7), Venus: Assessment of Models using Observations from Geological Mapping

Science.gov (United States)

Ivanov, M. A.; Head, James W.

2008-01-01

Lakshmi Planum is a high-standing plateau (3.5-4.5 km above MPR) surrounded by the highest mountain ranges on Venus. Lakshmi represents a unique type of elevated region different from dome-shaped and rifted rises and tessera-bearing crustal plateaus. The unique characteristics of Lakshmi suggest that it formed by an unusual combination of processes and played an important role in Venus geologic history. Lakshmi was studied with Venera-15/16 and Magellan data, resulting in two classes of models, divergent and convergent, to explain its unusual topographic and morphologic characteristics. Divergent models explain Lakshmi as a site of mantle upwelling due to rising and subsequent collapse of a mantle diapir; such models explain emplacement of a lava plateau inside Lakshmi and, in some circumstances, formation of the mountain ranges. The convergent models consider Lakshmi as a locus of mantle downwelling, convergence, underthrusting, and possible subduction. Key features in these models are the mountain ranges, high topography of Lakshmi interior, and the large volcanic centers in the plateau center. These divergent and convergent models entail principally different mechanisms of formation and suggest different geodynamic regimes on Venus. Almost all models make either explicit or implicit predictions about the type and sequence of major events during formation and evolution of Lakshmi and thus detailed geological mapping can be used to test them. Here we present the results of such geological mapping (the V-7 quadrangle, 50-75degN, 300-360degE; scale 1:5M) that allows testing the proposed models for Lakshmi.

Long-term evolution of the Campine area in Northern Belgium: past and expected future evolution of tectonics and climate

International Nuclear Information System (INIS)

De Craen, M.; Beerten, K.; Brassinnes, S.; Wouters, L.

2012-01-01

Document available in extended abstract form only. Disposal of radioactive waste in a geological repository involves the reliance, now and in the long-term future, on the geological and hydrogeological environment. In preparation of the safety and feasibility case 1 (SFC1), the long-term geodynamic evolution of Boom Clay and its geological environment in the Campine area in northern Belgium is studied. Time frames considered are the geological past and the future 1 million year. The idea is that the past long-term evolution can be extended to predict what might happen in the future. In this paper, we first focusses on the past long-term tectonic evolution of the Campine area, and make an extrapolation for the future 1 Ma. We then focus on past climate evolution, and similarly, an assessment of possible future climate conditions is made for the Campine area within the next 1 Ma. Another paper focusses on the combined effect of tectonics and climate on the evolution of the surface environment in the Campine area for the next 1 Ma, with respect to geomorphological, pedological and hydrological processes. During the Palaeozoic, the geodynamic evolution of the Campine area was mainly determined by tectonics. A large intermittently subsiding sedimentary basin existed in which large amounts of sediments were deposited, and which was protected by the Brabant Massif from major oro-genetic compressive processes. Palaeozoic sediments in the Campine Basin reach a maximum thickness of 4000 m. During Mesozoic and Cenozoic, its geodynamic evolution was the interactive result of plate tectonics, sea level changes and climate evolution. Further subsidence resulted in a thick sequence of sedimentary deposits. Mesozoic sediments are found throughout the Campine area while remains of Jurassic-Triassic sediments are found only in the central Roer Valley Graben in the east. The Cenozoic is characterised by a succession of sub-horizontal layers of Tertiary clays and sands and covered by

Volcanic rises on Venus: Geology, formation, and sequence of evolution

Science.gov (United States)

Senske, D. A.; Stofan, E. R.; Bindschadler, D. L.; Smrekar, S. E.

1993-01-01

Large centers of volcanism on Venus are concentrated primarily in the equatorial region of the planet and are associated with regional topographic rises. Analysis of both radar images and geophysical data suggest that these uplands are sites of mantle upwelling. Magellan radar imaging provides a globally contiguous data set from which the geology of these regions is evaluated and compared. In addition, high resolution gravity data currently being collected provide a basis to assess the relationship between these uplands and processes in the planet's interior. Studies of the geology of the three largest volcanic highlands (Beta Regio, Atla Regio, Western Eistla Regio) show them to be distinct, having a range of volcanic and tectonic characteristics. In addition to these large areas, a number of smaller uplands are identified and are being analyzed (Bell Regio, Imdr Regio, Dione Regio (Ushas, Innini, and Hathor Montes), and Themis Regio). To understand better the mechanisms by which these volcanic rises form and evolve, we assess their geologic and geophysical characteristics.

Constraints on the topographic evolution of Corsica and Sardinia from geological and geomorphic analyses

Science.gov (United States)

Quye-Sawyer, Jennifer; Whittaker, Alexander; Roberts, Gareth; Rood, Dylan

2017-04-01

The western Mediterranean Sea and its surroundings form part of a well-studied region whose geodynamic history is broadly known. However, how the topography of this area has responded to its tectonic and geodynamic influences is not fully understood. In particular, the relative importance of convergent, extensional and dynamic process is not known. Here we focus on the islands of Corsica, France, and Sardinia, Italy, which have played an important role in Alpine-Apennine system. They experienced a similar kinematic history during the Cenozoic, however their different positions on the Tethyan margin allow the relative effects of Alpine collision and rates of back-arc stretching to be compared. In particular, the two stages of back-arc extension (Liguro-Provençal basin to the west and Tyrrhenian Sea on the east) can provide information about how rollback-induced extension developed with time from the late Oligocene to the present. The two islands are historically tectonically quiescent, however they still preserve evidence of collision and subsequent extension from slab roll-back. In this study we have used a combination of geological and geomorphic techniques to provide new constraints into the vertical motions of Corsica and Sardinia. To quantify the spatial and temporal landscape evolution we have integrated stratigraphic, structural and thermochronological data and re-evaluated these alongside present-day geomorphic and geophysical observations. In addition, we have used digital elevation models to acquire 2030 fluvial longitudinal profiles for both islands. Knickpoints identified on these longitudinal profiles have been compared to geological maps to test the influence of rock strength on erosion. Our analysis reveals the presence of non-lithologically controlled knickpoints which we interpret to have been created by Miocene to Recent changes in uplift rate of the landscape. The longitudinal profiles were subsequently used in drainage inversion modelling, whose

Chirp subbottom profiler data collected in Pamlico Sound on cruise SndPt_05_21_22_2012 of RV Riggs for the Coastal Hydrodynamics and Natural Geologic Evolution (CHaNGE) project

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Edgetech 216 chirp data (SEG-Y format) collected for the Coastal Hydrodynamics and Natural Geologic Evolution (CHaNGE) project, OCE-1130843. Survey area covers...

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

Petrology and Geochemistry of Unbrecciated Harzburgitic Diogenite MIL 07001: A Window Into Vestan Geological Evolution

Science.gov (United States)

Mittlefehldt, D. W.; Peng, Z. X.; Mertzman, S. A.; Mertzman, K. R.

2014-01-01

There is a strong case that asteroid 4 Vesta is the parent of the howardite, eucrite and diogenite (HED) meteorites. Models developed for the geological evolution of Vesta can satisfy the compositions of basaltic eucrites that dominate in the upper crust. The bulk compositional characteristics of diogenites - cumulate harzburgites and orthopyroxenites from the lower crust - do not fit into global magma ocean models that can describe the compositions of basaltic and cumulate eucrites. Recent more detailed formation models do make provision for a more complicated origin for diogenites, but this model has yet to be completely vetted. Compositional studies of bulk samples has led to the hypothesis that many diogenites were formed late by interaction of their parent melts with a eucritic crust, but those observations may alternatively be explained by subsolidus equilibration of trace elements between orthopyroxene and plagioclase and Ca-phosphate in the rocks. Differences in radiogenic Mg-26 content between diogenites and eucrites favors early formation of the former, not later formation. Understanding the origin of diogenites is crucial for understanding the petrologic evolution of Vesta. We have been doing coordinated studies of a suite of diogenites including petrologic investigations, bulk rock major and trace element studies, and in situ trace element analyses of orthopyroxene. Here we will focus on an especially unusual, and potentially key, diogenite, MIL 07001.

A Passerine Bird's evolution corroborates the geologic history of the island of New Guinea.

Science.gov (United States)

Deiner, Kristy; Lemmon, Alan R; Mack, Andrew L; Fleischer, Robert C; Dumbacher, John P

2011-05-06

New Guinea is a biologically diverse island, with a unique geologic history and topography that has likely played a role in the evolution of species. Few island-wide studies, however, have examined the phylogeographic history of lowland species. The objective of this study was to examine patterns of phylogeographic variation of a common and widespread New Guinean bird species (Colluricincla megarhyncha). Specifically, we test the mechanisms hypothesized to cause geographic and genetic variation (e.g., vicariance, isolation by distance and founder-effect with dispersal). To accomplish this, we surveyed three regions of the mitochondrial genome and a nuclear intron and assessed differences among 23 of the 30 described subspecies from throughout their range. We found support for eight highly divergent lineages within C. megarhyncha. Genetic lineages were found within continuous lowland habitat or on smaller islands, but all individuals within clades were not necessarily structured by predicted biogeographic barriers. There was some evidence of isolation by distance and potential founder-effects. Mitochondrial DNA sequence divergence among lineages was at a level often observed among different species or even genera of birds (5-11%), suggesting lineages within regions have been isolated for long periods of time. When topographical barriers were associated with divergence patterns, the estimated divergence date for the clade coincided with the estimated time of barrier formation. We also found that dispersal distance and range size are positively correlated across lineages. Evidence from this research suggests that different phylogeographic mechanisms concurrently structure lineages of C. megarhyncha and are not mutually exclusive. These lineages are a result of evolutionary forces acting at different temporal and spatial scales concordant with New Guinea's geological history.

A Passerine Bird's evolution corroborates the geologic history of the island of New Guinea.

Directory of Open Access Journals (Sweden)

Kristy Deiner

2011-05-01

Full Text Available New Guinea is a biologically diverse island, with a unique geologic history and topography that has likely played a role in the evolution of species. Few island-wide studies, however, have examined the phylogeographic history of lowland species. The objective of this study was to examine patterns of phylogeographic variation of a common and widespread New Guinean bird species (Colluricincla megarhyncha. Specifically, we test the mechanisms hypothesized to cause geographic and genetic variation (e.g., vicariance, isolation by distance and founder-effect with dispersal. To accomplish this, we surveyed three regions of the mitochondrial genome and a nuclear intron and assessed differences among 23 of the 30 described subspecies from throughout their range. We found support for eight highly divergent lineages within C. megarhyncha. Genetic lineages were found within continuous lowland habitat or on smaller islands, but all individuals within clades were not necessarily structured by predicted biogeographic barriers. There was some evidence of isolation by distance and potential founder-effects. Mitochondrial DNA sequence divergence among lineages was at a level often observed among different species or even genera of birds (5-11%, suggesting lineages within regions have been isolated for long periods of time. When topographical barriers were associated with divergence patterns, the estimated divergence date for the clade coincided with the estimated time of barrier formation. We also found that dispersal distance and range size are positively correlated across lineages. Evidence from this research suggests that different phylogeographic mechanisms concurrently structure lineages of C. megarhyncha and are not mutually exclusive. These lineages are a result of evolutionary forces acting at different temporal and spatial scales concordant with New Guinea's geological history.

Evolution of the Atmosphere and Oceans: Evidence from Geological ...

Indian Academy of Sciences (India)

Geological Survey of India since 1974. ... sulphate bacteria, for instance, use H2S instead o[water, and CO2 to produce carbohydrates in the presence of light energy. ... weathering and in the oxidation of reduced gases of volcanic origin.

Geologic evolution of the Paraiba do Sul complex, in the central part of the Ribeira belt, based on the geochemistry and U-Pb geochronology studies

International Nuclear Information System (INIS)

Valladares, Claudia Sayao

1996-01-01

Aiming the definition of the Complexo Paraiba do Sul evolution, the work presents a geochronological approach by the U-Pb method, considered appropriate to study polideformed terrains. The minerals used to the U-Pb dating (zircon, titanite and monazite) provides information about the ages of rock generation and the successive geological events the rocks were submitted. The U-Pb geochronological approach is pioneer in the investigated area and two questions referent to the Complexo Paraiba do Sul evolution in the central part of the Ribeira belt, were the aim of this approach. The first of them refers to the crystallization epoch and the gneisses metamorphism, interpreted here like orthogneisses, called Unidade Quirino of the Complexo Paraiba do Sul. The second refers to the metamorphism ages and meta sedimentary unit deformation. Looking for the contribution to the Complexo Paraiba do Sul evolution understanding, this work presents the data based on the geologic map of this area, comprising part of the Folha Volta Redonda (1:50.000), including petrographic, structural and microtectonic studies. It also presents and discusses the results of: 17 U-Pb analysis in zircon and titanite of the Complexo Paraiba do Sul orthogneisses collection; 24 geochemical analysis of major, minor, trace elements and ETR of the same collection; an U-Pb analysis in titanite of the Unidade Sao Joao, 5 U-Pb analysis in titanites and/or monazites of granites and granitoids; 12 geochemical analysis including major, minor and trace elements and ETR, in granites and sills of leucogranites. Finally, the data achieved were integrated with the objective to elaborate an evolutive view of the Complexo Paraiba do Sul

Geology of the Río de la Plata and the surrounding areas of Argentina and Uruguay related to the evolution of the Atlantic margin

Science.gov (United States)

Rossello, Eduardo A.; Veroslavsky, Gerardo; de Santa Ana, Héctor; Rodríguez, Pablo

2018-04-01

An integrated study of geological and geophysical data of the Río de la Plata region and its relation to the evolution of the Atlantic passive margin is herein described. This characterization is based on the available geological and geophysical information and on the correlation of the southern end of the best-known Santa Lucía Basin in Uruguay to the Salado Basin in Argentina, and their connection through the Quilmes Trough. Furthermore, a new Meso-Cenozoic depocenter is characterized and identified as Recalada Trough, subparallely aligned to the Quilmes Trough and separated from it by the Magdalena-Montevideo High. Both sedimentary fillings present ENE-WSW trending main axes and reach an average thickness of almost 2000 m. This suggests an evolution from a triple junction where interconnected extensional arms developed, which have had common Mesozoic tectosedimentary histories related to the early opening of the Atlantic Ocean. Based on the geophysical and geological evidence, the previously accepted existence in the Río de la Plata of a first-order structural feature along the international border between Argentina and Uruguay, associated to an ENE-WSW trending tectonic high, identified as Martín García, is unjustified. The tectonic evolution of the Atlantic margin in front of the Río de la Plata estuary is the consequence of a long deformation history starting in the Precambrian up to recent times. Each Precambrian, Paleozoic, Mesozoic and Cenozoic tectonic scenario adds different weak trends on the continental crust, which control the evolution of the sedimentary depocenters. The presence of these tectosedimentary records influence the bathymetric control of the Río de la Plata and the dynamics of the recent estuarine deposits. The Meso-Cenozoic sedimentary infill is estimated to comprise considerable ranges of sandstones and conglomerates associated with faulted blocks of the crystalline basement, with expected petrophysical conditions oscillating in

Microstratigraphic logging of calcite fabrics in speleothems as tool for palaeoclimate studies

Directory of Open Access Journals (Sweden)

Silvia Frisia

2015-01-01

Full Text Available The systematic documentation of calcite fabrics in stalagmites and flowstones provides robustness to palaeoclimate interpretation based on geochemical proxies, but it has been neglected because it is difficult to transform crystal morphologies into numerical values, and construct fabric time series. Here, general criteria that allow for coding fabrics of calcite composing stalagmites and flowstones is provided. Being based on known models of fabric development, the coding ascribes sequential numbers to each fabric, which reflect climate-related parameters, such as changes in drip rate variability, bio-mediation or diagenetic modifications. Acronyms are proposed for Columnar types, Dendritic, Micrite, Microsparite and Mosaic fabrics, whose use could then render possible comparison of calcite fabrics in stalagmites and flowstones from diverse latitudinal and altitudinal settings. The climatic and environmental significance of similarities in the geochemical signals and trends analysed in coeval stalagmites and flowstones (or differences in the signals and trends will be more robust when compared with fabric time series. This is particularly true where, such as in the Holocene, changes in geochemical values may be subtle, yet fabrics may show changes related to variations in supersaturation, drip rate or input of detrital particles or organic compounds. The proposed microstratigraphic logging allows recognition of changes in stable isotope ratio or trace element values that can be ascribed to hydrology and diagenesis, with considerable improvement of reconstructions based on the chemical proxies of stalagmites and flowstones composed of calcite.

Geologic evolution of the Jemez Mountains and their potential for future volcanic activity

International Nuclear Information System (INIS)

Burton, B.W.

1982-01-01

Geophysical and geochemical data and the geologic history of the Rio Grande rift and the vicinity of the Jemez Mountains are summarized to determine the probability of future volcanic activity in the Los Alamos, New Mexico area. The apparent cyclic nature of volcanism in the Jemez Mountains may be related to intermittent thermal inputs into the volcanic system beneath the region. The Jemez lineament, an alignment of late Cenozoic volcanic centers that crosses the rift near Los Alamos, has played an important role in the volcanic evolution of the Jemez Mountains. Geophysical data suggest that there is no active shallow magma body beneath the Valles caldera, though magma probably exists at about 15 km beneath this portion of the rift. The rate of volcanism in the Jemez Mountains during the last 10 million years has been 5 x 10 -9 /km 2 /y. Lava or ash flows overriding Laboratory radioactive waste disposal sites would have little potential to release radionuclides to the environment. The probability of a new volcano intruding close enough to a radioactive waste disposal site to effect radionuclide release is 2 x 10 -7 /y

Significant achievements in the planetary geology program. Final report

International Nuclear Information System (INIS)

Head, J.W.

1978-12-01

Developments reported at a meeting of principal investigators for NASA's planetology geology program are summarized. Topics covered include the following: constraints on solar system formation; asteriods, comets, and satellites; constraints on planetary interiors; volatiles and regoliths; instrument development techniques; planetary cartography; geological and geochemical constraints on planetary evolution; fluvial processes and channel formation; volcanic processes; Eolian processes; radar studies of planetary surfaces; cratering as a process, landform, and dating method; and the Tharsis region of Mars. Activities at a planetary geology field conference on Eolian processes are reported and techniques recommended for the presentation and analysis of crater size-frequency data are included

Geologic-tectonic evolutional characteristics and prospecting potential for ISL-amenable sandstone-type uranium deposits; in Sichuan basin

International Nuclear Information System (INIS)

Liu Jianhua; Zhu Xiyang; Wang Sili; Wei Jisheng

2005-01-01

Through the analysis on geologic-tectonic evolution of Sichuan basin, authors of this paper suggest: because of the heterogeneity of the basin basement and cover structures resulting from the lateral dividing, those segments in the basin that experienced only weak tectonic activation, and those that were uplifted and eroded earlier have not been intensely deformed, and have not experienced long-period burying. Rocks in those segments are poorly consolidated and there exist conditions for the formation of large-area artesian slope at the transitional sites between uplifted and subsided areas, possessing favourable hydrogeologic conditions for long-term infiltration of groundwater. These areas must be the targets for prospecting for ISL-amenable sandstone-type uranium deposits. Correspondingly, the Triassic and Jurassic where loose sand bodies are hosted are prospecting target horizons for uranium. (authors)

A model for the analysis of a normal evolution scenarios for a deep geological granite repository for high-level radioactive waste

International Nuclear Information System (INIS)

Cormenzana Lopez, J.L.; Cunado, M.A.; Lopez, M.T.

1996-01-01

The methodology usually used to evaluate the behaviour of deep geological repositories for high-level radioactive wastes comprises three phases: Identification of factors (processes, characteristics and events) that can affect the repository. Generation of scenarios. In general, a normal evolution scenario (Reference Scenario) and various disruptive scenarios (earthquake, human intrusion, etc) are considered. Evaluation of the behaviour of the repository in each scenario. The normal evolution scenario taking into account all factors with a high probability of occurrence is the first to be analysed. The performance assessment of behaviour being carried out by ENRESA for the AGP Granite has led to the identification of 63 of these factors. To analyse repository behaviour in the normal evolution scenario, it is necessary to first of all create an integrated model of the global system. This is a qualitative model including the 63 factors identified. For a global view of a such a complex system, it is very useful to graphically display the relationship between factors in an Influence Diagram. This paper shows the Influence Diagram used in the analysis of the AGP Granite Reference Scenario. (Author)

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.

Geological evolution of the Antongil Craton, NE Madagascar

Science.gov (United States)

Schofield, D.I.; Thomas, Ronald J.; Goodenough, K.M.; De Waele, B.; Pitfield, P.E.J.; Key, R.M.; Bauer, W.; Walsh, G.J.; Lidke, D.J.; Ralison, A.V.; Rabarimanana, M.; Rafahatelo, J.-M.; Randriamananjara, T.

2010-01-01

The Antongil Craton, along with the Masora and Antananarivo cratons, make up the fundamental Archaean building blocks of the island of Madagascar. They were juxtaposed during the late-Neoproterozoic to early Palaeozoic assembly of Gondwana. In this paper we give a synthesis of the geology of the Antongil Craton and present previously published and new geochemical and U-Pb zircon analyses to provide an event history for its evolution.The oldest rocks in the Antongil Craton form a nucleus of tonalitic gneiss, characteristic of Palaeo-Mesoarchaean cratons globally, including phases dated between 3320 ?? 14. Ma to 3231 ?? 6. Ma and 3187 ?? 2. Ma to 3154 ?? 5. Ma. A series of mafic dykes was intruded into the Mesoarchaean tonalites and a sedimentary succession was deposited on the craton prior to pervasive deformation and migmatisation of the region. The age of deposition of the metasediments has been constrained from a volcanic horizon to around 3178 ?? 2. Ma and subject to migmatisation at around 2597 ?? 49. Ma. A subsequent magmatic episode generated voluminous, weakly foliated granitic rocks, that also included additions from both reworked older crustal material and younger source components. An earlier granodiorite-dominated assemblage, dated between 2570 ?? 18. Ma and 2542 ?? 5. Ma, is largely exposed in xenoliths and more continuously in the northern part of the craton, while a later monzogranite-dominated phase, dated between 2531 ?? 13. Ma and 2513 ?? 0.4. Ma is more widely developed. Together these record the stabilisation of the craton, attested to by the intrusion of a younger dyke swarm, the age of which is constrained by a sample of metagabbro dated at 2147 ?? 6. Ma, providing the first evidence for Palaeoproterozoic rocks from the Antongil Craton.The youngest events recorded in the isotopic record of the Antongil Craton are reflected in metamorphism, neocrystallisation and Pb-loss at 792 ?? 130. Ma to 763 ?? 13. Ma and 553 ?? 68. Ma. These events are

The evolution of the callovo-oxfordian argillite site, Eastern France

International Nuclear Information System (INIS)

Brulhet, J.

2004-01-01

In France, investigations on the feasibility of a repository for long-lived radioactive waste in a deep geological formation are carried out according to a regulatory framework (Basic Safety Rule, RFS III.2.f prescribing that the long-term geological evolution be taken into account to assess the dynamics of radionuclide transfers over the very long timescales involved. As a matter of fact, the period in the future is in the order of 1 million years and is consistent with the timescales of geological evolutions likely to be significant, especially at ground surface, due to fast and high-amplitude climate variations. In order to achieve that goal, external and internal geodynamic phenomena that would generate the potential evolution are studied both on the surface and deep underground. The purpose is to define a reference scenario where the evolution of the environment is induced by a series of very likely natural events in the future. In such a framework, the basis of the approach is to continue studying the geological evolution together with past situation analogies. The work also involves the description of one or several possible variations, such as potential extreme variations or disturbances of the evolution due to the impact of human activities. That aspect is particularly important with regard to the climate evolution, because of the hypotheses on the long-term effects of greenhouse gases. In that context, the goal is to forecast potential exceptional situations in the future with or without similar conditions in the past. (author)

Adaptive dynamics on an environmental gradient that changes over a geological time-scale.

Science.gov (United States)

Fortelius, Mikael; Geritz, Stefan; Gyllenberg, Mats; Toivonen, Jaakko

2015-07-07

The standard adaptive dynamics framework assumes two timescales, i.e. fast population dynamics and slow evolutionary dynamics. We further assume a third timescale, which is even slower than the evolutionary timescale. We call this the geological timescale and we assume that slow climatic change occurs within this timescale. We study the evolution of our model population over this very slow geological timescale with bifurcation plots of the standard adaptive dynamics framework. The bifurcation parameter being varied describes the abiotic environment that changes over the geological timescale. We construct evolutionary trees over the geological timescale and observe both gradual phenotypic evolution and punctuated branching events. We concur with the established notion that branching of a monomorphic population on an environmental gradient only happens when the gradient is not too shallow and not too steep. However, we show that evolution within the habitat can produce polymorphic populations that inhabit steep gradients. What is necessary is that the environmental gradient at some point in time is such that the initial branching of the monomorphic population can occur. We also find that phenotypes adapted to environments in the middle of the existing environmental range are more likely to branch than phenotypes adapted to extreme environments. Copyright © 2015 Elsevier Ltd. All rights reserved.

Lunar and Planetary Geology

Science.gov (United States)

Basilevsky, Alexander T.

2018-05-01

Lunar and planetary geology can be described using examples such as the geology of Earth (as the reference case) and geologies of the Earth's satellite the Moon; the planets Mercury, Mars and Venus; the satellite of Saturn Enceladus; the small stony asteroid Eros; and the nucleus of the comet 67P Churyumov-Gerasimenko. Each body considered is illustrated by its global view, with information given as to its position in the solar system, size, surface, environment including gravity acceleration and properties of its atmosphere if it is present, typical landforms and processes forming them, materials composing these landforms, information on internal structure of the body, stages of its geologic evolution in the form of stratigraphic scale, and estimates of the absolute ages of the stratigraphic units. Information about one body may be applied to another body and this, in particular, has led to the discovery of the existence of heavy "meteoritic" bombardment in the early history of the solar system, which should also significantly affect Earth. It has been shown that volcanism and large-scale tectonics may have not only been an internal source of energy in the form of radiogenic decay of potassium, uranium and thorium, but also an external source in the form of gravity tugging caused by attractions of the neighboring bodies. The knowledge gained by lunar and planetary geology is important for planning and managing space missions and for the practical exploration of other bodies of the solar system and establishing manned outposts on them.

Development of methodology to construct a generic conceptual model of river-valley evolution for performance assessment of HLW geological disposal

International Nuclear Information System (INIS)

Kawamura, Makoto; Tanikawa, Shin-ichi; Yasue, Ken-ichi; Niizato, Tadafumi

2011-01-01

In order to assess the long-term safety of a geological disposal system for high-level radioactive waste (HLW), it is important to consider the impact of uplift and erosion, which cannot be precluded on a timescale in the order of several hundred thousand years for many locations in Japan. Geomorphic evolution, caused by uplift and erosion and coupled to climatic and sea-level changes, will impact the geological disposal system due to resulting spatial and temporal changes in the disposal environment. Degradation of HLW barrier performance will be particularly significant when the remnant repository structures near, and are eventually exposed at, the ground surface. In previous studies, fluvial erosion was densified as the key concern in most settings in Japan. Interpretation of the impact of the phenomena at relevant locations in Japan has led to development of a generic conceptual model which contains the features typical at middle reach of rivers. Here, therefore, we present a methodology for development of a generic conceptual model based on best current understanding of fluvial erosion in Japan, which identifies the simplifications and uncertainties involved and assesses their consequences in the context of repository performance. (author)

Sicily in its Mediterranean geological frame

Energy Technology Data Exchange (ETDEWEB)

Broquet, P.

2016-10-01

The Island of Sicily is generally considered to be the geological link between the North African Fold Belt and the Appennines, in Italy. This comes from a cylindristic meaning and is only partly exact. As a matter of fact, Sicily is essentially Greek; Ionian. Up to Middle Cretaceous time, the Sicilian area was a submerged shoal in the sea or the Panormide area, bordering the Ionian Ocean. This shoal lay between the future North African Fold Belt and the Appennines, forming an intermediate link between the Appenninic, Apulian, Panormian and Tunisian platforms. It was only during the Middle to Upper Cretaceous that the Atlantic and Ligure Oceans merged, making a continuous relationship between the Appenninic, Sicilian and North African sedimentary series. The key time periods are the Permian, Cretaceous and Oligo-Miocene periods leading to the formation of the actual Calabro-Sicilian arc. From the Permian to the present, the Sicilian geological history pertains to three oceanic domains: Ionian, Ligurian and Atlantic, of which the Ionian and Ligurian were under the influence of Tethys (Neo and Paleo-Tethys). The Tethysian identity of Sicily constitutes the major aspect of its geological history. However, the European and African plate tectonic movements complicated its structure. During the Middle Miocene subduction, southern Sicily became African, meanwhile its north-eastern part became, in Pliocene time, Maghrebian by accretion. Sicily is thus a truly geological patchwork, but its main section remains Ionian and now constitutes a link between North Africa and the Appennines. With older data, but also by means of recent results, we will replace Sicily in its Mediterranean frame, giving the mean stages of its paleogeographical and then its tectonic evolution. We will review the calabro-sicilian arc evolution from the Oligocene, developing the actual context and recalling the main fundamental play of the Numidian flysch. (Author)

Plant water use efficiency over geological time--evolution of leaf stomata configurations affecting plant gas exchange.

Science.gov (United States)

Assouline, Shmuel; Or, Dani

2013-01-01

Plant gas exchange is a key process shaping global hydrological and carbon cycles and is often characterized by plant water use efficiency (WUE - the ratio of CO2 gain to water vapor loss). Plant fossil record suggests that plant adaptation to changing atmospheric CO2 involved correlated evolution of stomata density (d) and size (s), and related maximal aperture, amax . We interpreted the fossil record of s and d correlated evolution during the Phanerozoic to quantify impacts on gas conductance affecting plant transpiration, E, and CO2 uptake, A, independently, and consequently, on plant WUE. A shift in stomata configuration from large s-low d to small s-high d in response to decreasing atmospheric CO2 resulted in large changes in plant gas exchange characteristics. The relationships between gas conductance, gws , A and E and maximal relative transpiring leaf area, (amax ⋅d), exhibited hysteretic-like behavior. The new WUE trend derived from independent estimates of A and E differs from established WUE-CO2 trends for atmospheric CO2 concentrations exceeding 1,200 ppm. In contrast with a nearly-linear decrease in WUE with decreasing CO2 obtained by standard methods, the newly estimated WUE trend exhibits remarkably stable values for an extended geologic period during which atmospheric CO2 dropped from 3,500 to 1,200 ppm. Pending additional tests, the findings may affect projected impacts of increased atmospheric CO2 on components of the global hydrological cycle.

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-genetic classification for uranium deposits

International Nuclear Information System (INIS)

Terentiev, V.M.; Naumov, S.S.

1997-01-01

The paper describes a system for classification uranium deposits based on geological and genetic characteristics. The system is based on the interrelation and interdependence of uranium ore formation processes and other geological phenomena including sedimentation, magmatism and tectonics, as well as the evolution of geotectonic structures. Using these aspects, deposits are classified in three categories: endogenic - predominately hydrothermal and hydrothermal-metasomatic; exogenic - sedimentary diagenetic, biogenic sorption, and infiltrational; and polygenetic or composite types. The latter complex types includes: sedimentary/metamorphic and metamorphic and sedimentary/hydrothermal, where different ore generating processes have prevailed over a rock unit at different times. The 3 page classification is given in both the English and Russian languages. (author). 3 tabs

Evolution of the global water cycle on Mars: The geological evidence

Science.gov (United States)

Baker, V. R.; Gulick, V. C.

1993-01-01

The geological evidence for active water cycling early in the history of Mars (Noachian geological system or heavy bombardment) consists almost exclusively of fluvial valley networks in the heavily cratered uplands of the planet. It is commonly assumed that these landforms required explanation by atmospheric processes operating above the freezing point of water and at high pressure to allow rainfall and liquid surface runoff. However, it has also been documented that nearly all valley networks probably formed by subsurface outflow and sapping erosion involving groundwater outflow prior to surface-water flow. The prolonged ground-water flow also requires extensive water cycling to maintain hydraulic gradients, but is this done via rainfall recharge, as in terrestrial environments?

Earth's earliest biosphere: Its origin and evolution

International Nuclear Information System (INIS)

Schopf, J.W.

1983-01-01

Some of the subjects discussed are related to the early biogeologic history, the nature of the earth prior to the oldest known rock record, the early earth and the Archean rock record, the prebiotic organic syntheses and the origin of life, Precambrian organic geochemistry, the biochemical evolution of anaerobic energy conversion, the isotopic inferences of ancient biochemistries, Archean stromatolites providing evidence of the earth's earliest benthos, Archean microfossils, the geologic evolution of the Archean-Early Proterozoic earth, and the environmental evolution of the Archean-Early Proterozoic earth. Other topics examined are concerned with geochemical evidence bearing on the origin of aerobiosis, biological and biochemical effects of the development of an aerobic environment, Early Proterozoic microfossils, the evolution of earth's earliest ecosystems, and geographic and geologic data for processed rock samples. Attention is given to a processing procedure for abiotic samples and calculation of model atmospheric compositions, and procedures of organic geochemical analysis

A multi-disciplinary review of late Quaternary palaeoclimates and environments for Lesotho

Directory of Open Access Journals (Sweden)

Jennifer M. Fitchett

2016-07-01

Full Text Available Lesotho provides a unique context for palaeoclimatic research. The small country is entirely landlocked by South Africa, yet has considerable variation in topography, climate, and associated vegetation over an approximate east-west transect. The region has been of archaeological interest for over a century, and hosts many Early to Late Stone Age sites with occupation preceding 80 000 years before present. The eastern Lesotho highlands are of interest to periglacial and glacial geomorphologists because of their well-preserved relict landforms and contentious evidence for permafrost and niche glaciation during the late Quaternary. However, continuous proxy records for palaeoenvironmental reconstructions for Lesotho are scarce and hampered by a range of methodological shortfalls. These challenges include uncertain ages, poor sampling resolution, and proxies extracted from archaeological excavations for which there may be bias in selection. Inferences on palaeoclimates are thus based predominantly on archaeological and palaeogeomorphological evidence for discrete periods during the late Quaternary. This review paper presents a more detailed multidisciplinary synthesis of late Quaternary conditions in Lesotho. We simultaneously considered the varying data that contribute to the under-studied palaeoenvironmental record for southern Africa. The collective palaeoenvironmental data for eastern Lesotho were shown to be relatively contradictory, with considerable variations in contemporaneous palaeoclimatic conditions within the study area. We argue that although methodological challenges may contribute to this variation, the marked changes in topography result in contrasting late Quaternary palaeoenvironments. Such environments are characterised by similar contrasting microclimates and niche ecologies as are witnessed in the contemporary landscape. These spatial variations within a relatively small landlocked country are of importance in understanding

Advancing the use of noble gases in fluid inclusions of speleothems as a palaeoclimate proxy. Method and standardization

International Nuclear Information System (INIS)

Papp, L.; Palcsu, L.; Major, Z.; Svingor, E.

2010-01-01

Complete text of publication follows. Continental carbonates are essential archives of the past geological and climatological occurrences. Recently, fluid inclusions of carbonates have got into focus of palaeoclimate research. A new approach using temperature dependent gas solubilities might be a way that uses only physical laws, e.g. the Henry's law of solubility and gas partitioning models. The so-called noble gas temperature (NGT) can be calculated from the measured noble gas concentrations. This report describes how our first advancing steps towards obtaining NGT's from fluid inclusions and tiny water amounts have been preformed. To extract the water inclusions from the carbonate matrix, the most suitable treatment is to crush the carbonate under vacuum. The water released from the inclusions is then collected in a cold finger by freezing. The amount of the liberated water is measured via its vapour pressure in a certain volume (Fig. 1). The liberated dissolved noble gases which were in the fluid inclusions are separated by a cryo system, and then admitted into the static mode noble gas mass spectrometer sequentially. The calibration of the noble gas mass spectrometric measurements is performed by means of well known air aliquots. To check the reliability of the whole measurement procedure standard water samples have to be measured. As for standard samples, first we have prepared air equilibrated water (AEW) in conditioned circumstances. We fill copper capillaries with AEW. Having completed the copper capillary assemblage, the AEW is letting flow through the capillary (Fig. 2). The error of such a water determination is less than 1% in case of 1 μl of liquid water (Fig. 1) that allows us to determine accurate noble gas concentrations. The reproducibility of 40 Ar measurements is better than 0.6 %, while those of neon, krypton and xenon isotopes are 0.6-1.6 %, 0.9-2.2 % and 0.8-2.0 %, respectively. Theoretically, these precisions for noble gas concentrations

Physiognomic and chemical characters in wood as palaeoclimate proxies

NARCIS (Netherlands)

Poole, I.J.; Bergen, P.F. van

2006-01-01

Fossil wood is both abundant and ubiquitous through geological time and space. During growth the parent plant was directly influenced by the biotic and abiotic (including climatic-) factors in the surrounding environment. The climate affects wood production in a number of ways and it is the

Episodic events in long-term geological processes: A new classification and its applications

Directory of Open Access Journals (Sweden)

Dmitry A. Ruban

2018-03-01

Full Text Available Long-term geological processes are usually described with curves reflecting continuous changes in the characteristic parameters through the geological history, and such curves can be employed directly for recognition of episodic (relatively long-term events linked to these changes. The episodic events can be classified into several categories according to their scale (ordinary and anomalous events, “shape” (positive, negative, and neutral events, and relation to long-term trend change (successive, interruptive, facilitative, stabilizing, transformative, increasing, and decreasing. Many types of these events can be defined depending on the combination of the above-mentioned patterns. Of course, spatial rank, duration, and origin can be also considered in description of these events. The proposed classification can be applied to events in some real long-term geological processes, which include global sea-level changes, biodiversity dynamics, lithospheric plate number changes, and palaeoclimate changes. Several case examples prove the usefulness of the classification. It is established that the Early Valanginian (Early Cretaceous eustatic lowstand (the lowest position of the sea level in the entire Cretaceous was negative, but ordinary and only interruptive event. In the other case, it becomes clear that the only end-Ordovician and the Permian/Triassic mass extinctions transformed the trends of the biodiversity dynamics (from increase to decrease and from decrease to increase respectively, and the only Cretaceous/Paleogene mass extinction was really anomalous event on the Phanerozoic biodiversity curve. The new palaeontological data are employed to reconstruct the diversity dynamics of brachiopods in Germany (without the Alps and the Swiss Jura Mountains. The further interpretation of the both diversity curves implies that the Early Toarcian mass extinction affected the regional brachiopod faunas strongly, but this event was only decreasing

Contribution of the geology and geochemistry modelling to the petroleum industry

International Nuclear Information System (INIS)

Tissot, B.

1993-01-01

Evolution of modelling and model interpretation in the domain of geology, geophysics and geochemistry applied to petroleum industry, is first summarized. Hydrocarbon geological formation modelling is then presented in details with examples of kinetic models such as the discrete distribution and the Gaussian distribution based models, and the kerogene to petroleum process modelling. Petroleum basin modelling is also discussed with methods such as back-stripping, conductive thermal transfers, etc. 14 figs., 26 refs

Evolution of anuran assemblages in the Tertiary and Quaternary of Europe, in the context of palaeoclimate and palaeogeography

Czech Academy of Sciences Publication Activity Database

Rage, J.C.; Roček, Zbyněk

2003-01-01

Roč. 24, č. 2 (2003), s. 133-167 ISSN 0173-5373 R&D Projects: GA AV ČR IAA6013701 Institutional research plan: CEZ:AV0Z3013912 Keywords : Anura * evolution * Palaeogeography and palaeoclimatology Subject RIV: EH - Ecology, Behaviour Impact factor: 0.417, year: 2003 http://web.ebscohost.com/ehost/pdf?vid=3&hid=13&sid=290992f1-8204-46f5-8d76-b6960b2d1be8%40SRCSM1

Geological Mapping of the Lada Terra (V-56) Quadrangle, Venus

Science.gov (United States)

Kumar, P. Senthil; Head, James W., III

2009-01-01

Geological mapping of the V-56 quadrangle (Fig. 1) reveals various tectonic and volcanic features and processes in Lada Terra that consist of tesserae, regional extensional belts, coronae, volcanic plains and impact craters. This study aims to map the spatial distribution of different material units, deformational features or lineament patterns and impact crater materials. In addition, we also establish the relative age relationships (e.g., overlapping or cross-cutting relationship) between them, in order to reconstruct the geologic history. Basically, this quadrangle addresses how coronae evolved in association with regional extensional belts, in addition to evolution of tesserae, regional plains and impact craters, which are also significant geological units of Lada Terra.

The application of geological computer modelling systems to the characterisation and assessment of radioactive waste repositories

International Nuclear Information System (INIS)

White, M.J.; Del Olmo, C.

1996-01-01

The deep disposal of radioactive waste requires the collection and analysis of large amounts of geological data. These data give information on the geological and hydrogeological setting of repositories and research sites, including the geological structure and the nature of the groundwater. The collection of these data is required in order to develop an understanding of the geology and the geological evolution of sites and to provide quantitative information for performance assessments. An integrated approach to the interpretation and provision of these data is proposed in this paper, via the use of computer systems, here termed geological modelling systems. Geological modelling systems are families of software programmes which allow the incorporation of site investigation data into integrated 3D models of sub-surface geology

Geology of Libya Montes and the Interbasin Plains of Northern Tyrrhena Terra, Mars: Project Introduction and First Year Work Plan

Science.gov (United States)

Skiner, J. A., Jr.; Rogers, A. D.; Seelos, K. D.

2009-01-01

The highland-lowland boundary (HLB) of Mars is interpreted to be a complex tectonic and erosional transition that may hold evidence for past geologic processes and environments. The HLB-abutting margin of the Libya Montes and the interbasin plains of northern Tyrrhena Terra display an exceptional view of the earliest to middle history of Mars that has yet to be fully characterized. This region contains some of the oldest exposed materials on the Martian surface as well as aqueous mineral signatures that may be potential chemical artifacts of early highland formational processes. However, a full understanding of the regions geologic and stratigraphic evolution is remarkably lacking. Some outstanding questions regarding the geologic evolution of Libya Montes and northern Tyrrhena Terra in-clude: Does combining geomorphology and composition advance our understanding of the region s evolution? Can highland materials be subdivided into stratigraphically discrete rock and sediment sequences? What do major physiographic transitions imply about the balanced tectonism, climate change, and erosion? Where is the erosional origin and what is the post-depositional history of channel and plains units? When and in what types of environments did aqueous mineral signatures arise? This abstract introduces the geologic setting, science rationale, and first year work plan of a recently-funded 4-year geologic mapping proposal (project year = calendar year). The objective is to delineate the geologic evolution of Libya Montes and northern Tyrrhena Terra at 1:1M scale using both classical geomorphological and compositional mapping techniques. The funded quadrangles are MTMs 00282, -05282, -10282, 00277, -05277, and -10277.

The geologic history of Margaritifer basin, Mars

Science.gov (United States)

Salvatore, M. R.; Kraft, M. D.; Edwards, Christopher; Christensen, P.R.

2016-01-01

In this study, we investigate the fluvial, sedimentary, and volcanic history of Margaritifer basin and the Uzboi-Ladon-Morava (ULM) outflow channel system. This network of valleys and basins spans more than 8000 km in length, linking the fluvially dissected southern highlands and Argyre Basin with the northern lowlands via Ares Vallis. Compositionally, thermophysically, and morphologically distinct geologic units are identified and are used to place critical relative stratigraphic constraints on the timing of geologic processes in Margaritifer basin. Our analyses show that fluvial activity was separated in time by significant episodes of geologic activity, including the widespread volcanic resurfacing of Margaritifer basin and the formation of chaos terrain. The most recent fluvial activity within Margaritifer basin appears to terminate at a region of chaos terrain, suggesting possible communication between surface and subsurface water reservoirs. We conclude with a discussion of the implications of these observations on our current knowledge of Martian hydrologic evolution in this important region.

Geology of Southern Quintana Roo (Mexico) and the Chicxulub Ejecta Blanket

Science.gov (United States)

Schönian, F.; Tagle, R.; Stöffler, D.; Kenkmann, T.

2005-03-01

In southern Quintana Roo (Mexico) the Chicxulub ejecta blanket is discontinuously filling a karstified pre-KT land surface. This suggests a completely new scenario for the geological evolution of the southern Yucatán Peninsula.

NEA perspectives on timescales and criteria in post-closure safety of geological disposal

International Nuclear Information System (INIS)

Preter, P. de; Smith, P.; Pescatore, C.; Forinash, B.

2006-01-01

A key challenge in the development of safety cases for geological repositories is associated with the long periods of time over which radioactive wastes that are disposed of in repositories remain hazardous. The OECD Nuclear Energy Agency (NEA) has recently examined issues related to timescales in the context of two projects under the auspices of the Radioactive Waste Management Committee (RWMC): the Timescales Initiative and the Long-Term Safety Criteria (LTSC) Initiative. These projects examine, respectively, the treatment of timescales in actual safety cases and in the development of radiological protection criteria for geological disposal. They treat different aspects of timescales but have some overlap and have shown some convergence of the results achieved to date. Based on these projects, this paper examines general considerations in the handling of timescales, including ethical principles, evolution of the hazards of radioactive waste over time, and uncertainty in the evolution of repository systems (including geological features). The implications of these considerations are examined in terms of repository siting; levels of protection in regulations; planning for pre-closure and post-closure actions; and development and presentation of safety cases. A comparison is made with previous NEA work related to timescales, in order to show evolutions in current understanding. (authors)

NEA perspectives on timescales and criteria in post-closure safety of geological disposal

Energy Technology Data Exchange (ETDEWEB)

Preter, P. de [ONDRAF/NIRAS, Brussels (Belgium); Smith, P. [Safety Assessment Management Ltd, SAM Ltd. (United Kingdom); Pescatore, C.; Forinash, B. [OECD/NEA, Nuclear Energy Agency, 92 - Issy les Moulineaux (France)

2006-07-01

A key challenge in the development of safety cases for geological repositories is associated with the long periods of time over which radioactive wastes that are disposed of in repositories remain hazardous. The OECD Nuclear Energy Agency (NEA) has recently examined issues related to timescales in the context of two projects under the auspices of the Radioactive Waste Management Committee (RWMC): the Timescales Initiative and the Long-Term Safety Criteria (LTSC) Initiative. These projects examine, respectively, the treatment of timescales in actual safety cases and in the development of radiological protection criteria for geological disposal. They treat different aspects of timescales but have some overlap and have shown some convergence of the results achieved to date. Based on these projects, this paper examines general considerations in the handling of timescales, including ethical principles, evolution of the hazards of radioactive waste over time, and uncertainty in the evolution of repository systems (including geological features). The implications of these considerations are examined in terms of repository siting; levels of protection in regulations; planning for pre-closure and post-closure actions; and development and presentation of safety cases. A comparison is made with previous NEA work related to timescales, in order to show evolutions in current understanding. (authors)

Continued internal and external research efforts of RAG. New insights for the geological evolution of the Molasse Basin of Austria

Energy Technology Data Exchange (ETDEWEB)

Hinsch, R. [Rohoel-Aufsuchungs AG, Vienna (Austria)

2008-10-23

The understanding of the detailed geological evolution of the Molasse Basin is crucial for the continued success of exploration in this mature basin. Results from several research projects help to find new play types and increase the understanding of stratigraphic traps by characterising the sedimentological processes that control them. Risks associated with play types can be better assessed considering their evolutionary framework. Several studies focussed on that subject have been concluded in recent years or are still ongoing. This presentation will give an overview of the objectives, results and implications of these initiatives for evaluation and analysis of the geological evolution and for exploration of the Molasse Basin. An initial collaboration with Stanford University integrated sedimentological core analyses with 3D seismic, wireline log data interpretation and outcrop studies in analogue settings. The study yielded a modern sedimentological model for the Upper Puchkirchen Formation which was subsequently applied to exploration. A sequence stratigraphic study examined the sequence framework of the Molasse Basin fill and was able to correlate 5 sequences from the shelf into the deep basin. Studies on seismic and core analyses from the south slope of the Puchkirchen trough show how slope morphology and confinement control sediment distribution in the southern slope deposits. The transition from deep to more shallow marine conditions and the progradation of deltaic sequences into the basin in Eggenburgian/Burdigalian times is described by an intense 3-D seismic interpretation in combination with sedimentological core work. Working on a more local scale, other projects are improving the understanding of the detailed architecture of distinct play elements such as the Upper Puchkirchen Channel or the Basal Hall Formation Channel. In general, these studies highlight the complex interaction of processes that control sediment distribution in the basin. Morphology

Planetary Geologic Mapping Handbook - 2009

Science.gov (United States)

Tanaka, K. L.; Skinner, J. A.; Hare, T. M.

2009-01-01

. Terrestrial geologic maps published by the USGS now are primarily digital products using geographic information system (GIS) software and file formats. GIS mapping tools permit easy spatial comparison, generation, importation, manipulation, and analysis of multiple raster image, gridded, and vector data sets. GIS software has also permitted the development of project-specific tools and the sharing of geospatial products among researchers. GIS approaches are now being used in planetary geologic mapping as well (e.g., Hare and others, 2009). Guidelines or handbooks on techniques in planetary geologic mapping have been developed periodically (e.g., Wilhelms, 1972, 1990; Tanaka and others, 1994). As records of the heritage of mapping methods and data, these remain extremely useful guides. However, many of the fundamental aspects of earlier mapping handbooks have evolved significantly, and a comprehensive review of currently accepted mapping methodologies is now warranted. As documented in this handbook, such a review incorporates additional guidelines developed in recent years for planetary geologic mapping by the NASA Planetary Geology and Geophysics (PGG) Program s Planetary Cartography and Geologic Mapping Working Group s (PCGMWG) Geologic Mapping Subcommittee (GEMS) on the selection and use of map bases as well as map preparation, review, publication, and distribution. In light of the current boom in planetary exploration and the ongoing rapid evolution of available data for planetary mapping, this handbook is especially timely.

Directions of the US Geological Survey Landslide Hazards Reduction Program

Science.gov (United States)

Wieczorek, G.F.

1993-01-01

The US Geological Survey (USGS) Landslide Hazards Reduction Program includes studies of landslide process and prediction, landslide susceptibility and risk mapping, landslide recurrence and slope evolution, and research application and technology transfer. Studies of landslide processes have been recently conducted in Virginia, Utah, California, Alaska, and Hawaii, Landslide susceptibility maps provide a very important tool for landslide hazard reduction. The effects of engineering-geologic characteristics of rocks, seismic activity, short and long-term climatic change on landslide recurrence are under study. Detailed measurement of movement and deformation has begun on some active landslides. -from Author

Geologic database for digital geology of California, Nevada, and Utah: an application of the North American Data Model

Science.gov (United States)

Bedford, David R.; Ludington, Steve; Nutt, Constance M.; Stone, Paul A.; Miller, David M.; Miller, Robert J.; Wagner, David L.; Saucedo, George J.

2003-01-01

The USGS is creating an integrated national database for digital state geologic maps that includes stratigraphic, age, and lithologic information. The majority of the conterminous 48 states have digital geologic base maps available, often at scales of 1:500,000. This product is a prototype, and is intended to demonstrate the types of derivative maps that will be possible with the national integrated database. This database permits the creation of a number of types of maps via simple or sophisticated queries, maps that may be useful in a number of areas, including mineral-resource assessment, environmental assessment, and regional tectonic evolution. This database is distributed with three main parts: a Microsoft Access 2000 database containing geologic map attribute data, an Arc/Info (Environmental Systems Research Institute, Redlands, California) Export format file containing points representing designation of stratigraphic regions for the Geologic Map of Utah, and an ArcView 3.2 (Environmental Systems Research Institute, Redlands, California) project containing scripts and dialogs for performing a series of generalization and mineral resource queries. IMPORTANT NOTE: Spatial data for the respective stage geologic maps is not distributed with this report. The digital state geologic maps for the states involved in this report are separate products, and two of them are produced by individual state agencies, which may be legally and/or financially responsible for this data. However, the spatial datasets for maps discussed in this report are available to the public. Questions regarding the distribution, sale, and use of individual state geologic maps should be sent to the respective state agency. We do provide suggestions for obtaining and formatting the spatial data to make it compatible with data in this report. See section ‘Obtaining and Formatting Spatial Data’ in the PDF version of the report.

A new quantitative approach to identify reworking in Eocene to Miocene pollen records from offshore Antarctica using red fluorescence and digital imaging

NARCIS (Netherlands)

Strother, Stephanie L.; Salzmann, Ulrich; Sangiorgi, Francesca|info:eu-repo/dai/nl/304836982; Bijl, Peter K.|info:eu-repo/dai/nl/314028110; Pross, Jorg; Escutia, Carlota; Salabarnada, Ariadna; Pound, Matthew J.; Voss, Jochen; Woodward, John

2017-01-01

Antarctic palaeoclimate evolution and vegetation history after the formation of a continent-scale cryosphere at the Eocene-Oligocene boundary, 33.9 million years ago, has remained a matter of controversy. In particular, the reconstruction of terrestrial climate and vegetation has been strongly

Drawing 1/100,000 scale geological map of Mt. Hakkoda geothermal district

Energy Technology Data Exchange (ETDEWEB)

Muraoka, Hirobumi; Takakura, Shin' ichi

1987-10-01

Geological map of geothermal district of Mt. Hakkoda was made which included the main volcanos created after Pliocene era. For the purpose, geothermal liquid, terrestial heat sources and its storing structures, were studied with consulting geological map. Aerial and satelite photographs were used for the study of faults, foldings, and dikes,. By the result, stratigragic order of layers, developing process of vocanos, and evoluting process of magma, were summarized for report. (5 figs, 4 tabs, 101 refs)

A methodology for scenario development based on understanding of long-term evolution of geological disposal systems

International Nuclear Information System (INIS)

Wakasugi, Keiichiro; Ishiguro, Katsuhiko; Ebashi, Takeshi; Ueda, Hiroyoshi; Koyama, Toshihiro; Shiratsuchi, Hiroshi; Yashio, Shoko; Kawamura, Hideki

2012-01-01

We have developed a 'hybrid' scenario development method by combining bottom-up and top-down approaches and applied for the case of geological disposal of high-level waste. This approach provides a top-down perspective, by introducing a concept of safety functions for different periods and 'storyboards', which depict repository evolution with time on a range of spatial scales, and a bottom-up perspective, by identifying relationship between processes related to radionuclide migration and safety functions based on feature, event and process (FEP) management. Based on a trial study, we have specified work descriptions for each step of the hybrid scenario development methodology and confirmed that the storyboard provides a baseline and holistic overview for the FEP management and a common platform to involve close interaction with experts in various disciplines to understand the crossover phenomenological processes. We also confirmed that there is no conflict between the top-down approach and the bottom-up approach and the hybrid scenario development work frame fulfils the specified requirements for traceability, comprehensiveness, ease of understanding, integration of multidisciplinary knowledge and applicability to a staged approach to siting. (author)

Planetary Geologic Mapping Handbook - 2010. Appendix

Science.gov (United States)

Tanaka, K. L.; Skinner, J. A., Jr.; Hare, T. M.

2010-01-01

the USGS now are primarily digital products using geographic information system (GIS) software and file formats. GIS mapping tools permit easy spatial comparison, generation, importation, manipulation, and analysis of multiple raster image, gridded, and vector data sets. GIS software has also permitted the development of projectspecific tools and the sharing of geospatial products among researchers. GIS approaches are now being used in planetary geologic mapping as well. Guidelines or handbooks on techniques in planetary geologic mapping have been developed periodically. As records of the heritage of mapping methods and data, these remain extremely useful guides. However, many of the fundamental aspects of earlier mapping handbooks have evolved significantly, and a comprehensive review of currently accepted mapping methodologies is now warranted. As documented in this handbook, such a review incorporates additional guidelines developed in recent years for planetary geologic mapping by the NASA Planetary Geology and Geophysics (PGG) Program's Planetary Cartography and Geologic Mapping Working Group's (PCGMWG) Geologic Mapping Subcommittee (GEMS) on the selection and use of map bases as well as map preparation, review, publication, and distribution. In light of the current boom in planetary exploration and the ongoing rapid evolution of available data for planetary mapping, this handbook is especially timely.

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.

New insights on the geological evolution of the continental margin of Southeastern Brazil derived from zircon and apatite (U-Th-Sm)/He and fission-track data

Science.gov (United States)

Krob, Florian; Stippich, Christian; Glasmacher, Ulrich A.; Hackspacher, Peter

2017-04-01

New insights on the geological evolution of the continental margin of Southeastern Brazil derived from zircon and apatite (U-Th-Sm)/He and fission-track data Krob, F.C.1, Stippich, C. 1, Glasmacher, U.A.1, Hackspacher, P.C.2 (1) Institute of Earth Sciences, Research Group Thermochronology and Archaeometry, Heidelberg University, INF 234, 69120, Heidelberg, Germany (2) Instituto de Geociências e Ciências Exatas, Universidade Estadual Paulista, Av. 24-A, 1515 Rio Claro, SP, 13506-900, Brazil Passive continental margins are important geoarchives related to mantle dynamics, the breakup of continents, lithospheric dynamics, and other processes. The main concern yields the quantifying long-term lithospheric evolution of the continental margin between São Paulo and Laguna in southeastern Brazil since the Neoproterozoic. We put special emphasis on the reactivation of old fracture zones running into the continent and their constrains on the landscape evolution. In this contribution, we represent already consisting thermochronological data attained by fission-track and (U-Th-Sm)/He analysis on apatites and zircons. The zircon fission-track ages range between 108.4 (15.0) and 539.9 (68.4) Ma, the zircon (U-Th-Sm)/He ages between 72.9 (5.8) and 427.6 (1.8) Ma whereas the apatite fission-track ages range between 40.0 (5.3) and 134.7 (8.0) Ma, and the apatite (U-Th-Sm)/He ages between 32.1 (1.52) and 92.0 (1.86) Ma. These thermochronological ages from metamorphic, sedimentary and intrusive rocks show six distinct blocks (Laguna, Florianópolis, Curitiba, Ilha Comprida, Peruibe and Santos) with different evolution cut by old fracture zones. Furthermore, models of time-temperature evolution illustrate the differences in Pre- to post-rift exhumation histories of these blocks. The presented data will provide an insight into the complex exhumation history of the continental margin based on the existing literature data on the evolution of the Paraná basin in Brazil and the latest

Temporal variations in the gene expression levels of cyanobacterial anti-oxidant enzymes through geological history: implications for biological evolution during the Great Oxidation Event

Science.gov (United States)

Harada, M.; Furukawa, R.; Yokobori, S. I.; Tajika, E.; Yamagishi, A.

2016-12-01

A significant rise in atmospheric O2 levels during the GOE (Great Oxidation Event), ca. 2.45-2.0 Ga, must have caused a great stress to biosphere, enforcing life to adapt to oxic conditions. Cyanobacteria, oxygenic photosynthetic bacteria that had been responsible for the GOE, are at the same time one of the organisms that would have been greatly affected by the rise of O2 level in the surface environments. Knowledge on the evolution of cyanobacteria is not only important to elucidate the cause of the GOE, but also helps us to better understand the adaptive evolution of life in response to the GOE. Here we performed phylogenetic analysis of an anti-oxidant enzyme Fe-SOD (iron superoxide dismutase) of cyanobacteria, to assess the adaptive evolution of life under the GOE. The rise of O2 level must have increased the level of toxic reactive oxygen species in cyanobacterial cells, thus forced them to change activities or the gene expression levels of Fe-SOD. In the present study, we focus on the change in the gene expression levels of the enzyme, which can be estimated from the promoter sequences of the gene. Promoters are DNA sequences found upstream of protein encoding regions, where RNA polymerase binds and initiates transcription. "Strong" promoters that efficiently interact with RNA polymerase induce high rates of transcription, leading to high levels of gene expression. Thus, from the temporal changes in the promoter sequences, we can estimate the variations in the gene expression levels during the geological time. Promoter sequences of Fe-SOD at each ancestral node of cyanobacteria were predicted from phylogenetic analysis, and the ancestral promoter sequences were compared to the promoters of known highly expressed genes. The similarity was low at the time of the emergence of cyanobacteria; however, increased at the branching nodes diverged 2.4 billon years ago. This roughly coincided with the onset of the GOE, implying that the transition from low to high gene

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

Proceedings of the symposium on isotope geology progress: technology, methods, theory and application

International Nuclear Information System (INIS)

2003-11-01

The symposium was held in Beijing, Nov. 7-11, and the proceedings collects 122 articles, the contents include: new technology and new methods on isotopic test; isotope fractionation mechanism; the early evolution of the solar system and the Earth; continental dynamics and evolution of orogenic belts; minerals, energy and water; major history events on life origin, evolution and geology; changes in the Earth's global and modern environment--the oceans, the atmosphere, rivers and lakes, karst and soil, ecological agriculture and modern environment

Natural climate variations in a geological perspective

International Nuclear Information System (INIS)

Mikkelsen, N.; Kuijpers, A.

2001-01-01

The climate is constantly changing, and it has been changing throughout the geological history of the Earth. These natural changes have shown a variability with frequencies from millions of years to just a few hundreds or tens of years. Some of the variations have been rather dramatic - shifting from globally uniform and hot climates to regular ice ages - whereas other changes have been less spectacular. All natural climate variations have an impact on the physical and biological systems of the Earth - and on mankind and culture during the last hundred thousand years. In this chapter we shall discuss the natural climate changes that has taken place during the geological history of the Earth and comment on the impact of these changes on the cultural evolution of mankind with special emphasis on Greenland. (LN)

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.

Geology of Joshua Tree National Park geodatabase

Science.gov (United States)

Powell, Robert E.; Matti, Jonathan C.; Cossette, Pamela M.

2015-09-16

The database in this Open-File Report describes the geology of Joshua Tree National Park and was completed in support of the National Cooperative Geologic Mapping Program of the U.S. Geological Survey (USGS) and in cooperation with the National Park Service (NPS). The geologic observations and interpretations represented in the database are relevant to both the ongoing scientific interests of the USGS in southern California and the management requirements of NPS, specifically of Joshua Tree National Park (JOTR).Joshua Tree National Park is situated within the eastern part of California’s Transverse Ranges province and straddles the transition between the Mojave and Sonoran deserts. The geologically diverse terrain that underlies JOTR reveals a rich and varied geologic evolution, one that spans nearly two billion years of Earth history. The Park’s landscape is the current expression of this evolution, its varied landforms reflecting the differing origins of underlying rock types and their differing responses to subsequent geologic events. Crystalline basement in the Park consists of Proterozoic plutonic and metamorphic rocks intruded by a composite Mesozoic batholith of Triassic through Late Cretaceous plutons arrayed in northwest-trending lithodemic belts. The basement was exhumed during the Cenozoic and underwent differential deep weathering beneath a low-relief erosion surface, with the deepest weathering profiles forming on quartz-rich, biotite-bearing granitoid rocks. Disruption of the basement terrain by faults of the San Andreas system began ca. 20 Ma and the JOTR sinistral domain, preceded by basalt eruptions, began perhaps as early as ca. 7 Ma, but no later than 5 Ma. Uplift of the mountain blocks during this interval led to erosional stripping of the thick zones of weathered quartz-rich granitoid rocks to form etchplains dotted by bouldery tors—the iconic landscape of the Park. The stripped debris filled basins along the fault zones.Mountain ranges

Natural analogues: studies of geological processes relevant to radioactive waste disposal in deep geological repositories

Energy Technology Data Exchange (ETDEWEB)

Russel, A.W. [Bedrock Geosciences, Auenstein (Switzerland); Reijonen, H.M. [Saanio and Rickkola Oy, Helsinki (Finland); McKinley, I.G. [MCM Consulting, Baden-Daettwil (Switzerland)

2015-06-15

The geological disposal of radioactive wastes is generally accepted to be the most practicable approach to handling the waste inventory built up from over 70 years accumulation of power production, research-medical-industrial and military wastes. Here, a brief overview of the approach to geological disposal is presented along with some information on repository design and the assessment of repository post-closure safety. One of the significant challenges for repository safety assessment is how to extrapolate the likely long-term (i.e. ten thousand to a million years) behaviour of the repository from the necessarily short term data from analytical laboratories and underground rock laboratories currently available. One approach, common to all fields of the geosciences, but also in such diverse fields as philosophy, biology, linguistics, law, etc., is to utilise the analogue argumentation methodology. For the specific case of radioactive waste management, the term 'natural analogue' has taken on a particular meaning associated with providing supporting arguments for a repository safety assessment. This approach is discussed here with a brief overview of how the study of natural (and, in particular, geological) systems can provide supporting information on the likely long-term evolution of a deep geological waste repository. The overall approach is discussed and some relevant examples are presented, including the use of uranium ore bodies to assess waste form stability, the investigation of native metals to define the longevity of waste containers and how natural clays can provide information on the stability of waste tunnel backfill material. (authors)

Natural analogues: studies of geological processes relevant to radioactive waste disposal in deep geological repositories

International Nuclear Information System (INIS)

Russel, A.W.; Reijonen, H.M.; McKinley, I.G.

2015-01-01

The geological disposal of radioactive wastes is generally accepted to be the most practicable approach to handling the waste inventory built up from over 70 years accumulation of power production, research-medical-industrial and military wastes. Here, a brief overview of the approach to geological disposal is presented along with some information on repository design and the assessment of repository post-closure safety. One of the significant challenges for repository safety assessment is how to extrapolate the likely long-term (i.e. ten thousand to a million years) behaviour of the repository from the necessarily short term data from analytical laboratories and underground rock laboratories currently available. One approach, common to all fields of the geosciences, but also in such diverse fields as philosophy, biology, linguistics, law, etc., is to utilise the analogue argumentation methodology. For the specific case of radioactive waste management, the term 'natural analogue' has taken on a particular meaning associated with providing supporting arguments for a repository safety assessment. This approach is discussed here with a brief overview of how the study of natural (and, in particular, geological) systems can provide supporting information on the likely long-term evolution of a deep geological waste repository. The overall approach is discussed and some relevant examples are presented, including the use of uranium ore bodies to assess waste form stability, the investigation of native metals to define the longevity of waste containers and how natural clays can provide information on the stability of waste tunnel backfill material. (authors)

2005 dossier: clay. Tome: safety evaluation of the geologic disposal

International Nuclear Information System (INIS)

2005-01-01

This document makes a status of the researches carried out by the French national agency of radioactive wastes (ANDRA) about the safety aspects of an argilite-type geologic disposal facility for high-level and long-lived (HLLL) radioactive wastes. Content: 1 - safety approach: context and general goals, general safety principles, specificity of the argilite repository safety approach, general approach; 2 - general description: HLLL wastes, geologic context of the Meuse/Haute-Marne site, repository architecture; 3 - safety functions and disposal design: time and space scales, safety approach by functions, functional analysis methodology, analysis of safety functions during the construction, exploitation and observation phases, safety functions analysis during post-closure phase; 4 - operational safety: dosimetric evaluation, risk analysis (explosible gases, fire hazards, lift cage drop, container drop); 5 - long-term efficiency of the disposal facility: normal evolution scenario, from conceptual models to the safety calculation model, description of the safety model, quantitative evaluation of the normal evolution scenario, main lessons learnt from the efficiency analysis; 6 - management of uncertainties: identification, building up of altered situations, mastery of uncertainties; 7 - evaluation of altered evolution scenarios: sealing defect scenario, container defect scenario, drilling scenario, strongly degraded operation scenario; 8 - conclusions: lessons learnt, possible improvements. (J.S.)

Lacustrine couplet-lamination: evidence for Late Pennsylvanian seasonality in central equatorial Pangaea (Stephanian B, Mšec Member, Central and Western Bohemian basins)

Czech Academy of Sciences Publication Activity Database

Lojka, R.; Sýkorová, Ivana; Laurin, Jiří; Matysová, Petra; Matys Grygar, Tomáš

2010-01-01

Roč. 85, č. 4 (2010), s. 709-734 ISSN 1214-1119 R&D Projects: GA AV ČR KJB307020601; GA AV ČR IAA300460804 Institutional research plan: CEZ:AV0Z30120515; CEZ:AV0Z30460519; CEZ:AV0Z40320502 Keywords : lamination * cyclicity * freshwater lake * dispersed organic matter * siderite * palaeoclimate Subject RIV: DB - Geology ; Mineralogy Impact factor: 1.202, year: 2010

Radioactive waste disposal in geological formations

International Nuclear Information System (INIS)

Gera, F.

1977-01-01

The nuclear energy controversy, now raging in several countries, is based on two main issues: the safety of nuclear plants and the possibility to dispose safely of the long-lived radioactive wastes. Consideration of the evolution of the hazard potential of waste in function of decay time leads to a somewhat conservative reference containment time in the order of one hundred thousand years. Several concepts have been proposed for the disposal of long-lived wastes. At the present time, emplacement into suitable geological formations under land areas can be considered the most promising disposal option. It is practically impossible to define detailed criteria to be followed in selecting suitable sites for disposal of long-lived wastes. Basically there is a single criterion, namely; that the geological environment must be able to contain the wastes for at least a hundred thousand years. However, due to the extreme variability of geological settings, it is conceivable that this basic capability could be provided by a great variety of different conditions. The predominant natural mechanism by which waste radionuclides could be moved from a sealed repository in a deep geological formation into the biosphere is leaching and transfer by ground water. Hence the greatest challenge is to give a satisfactory demonstration that isolation from ground water will persist over the required containment time. Since geological predictions are necessarily affected by fairly high levels of uncertainty, the only practical approach is not a straight-forward forecast of future geological events, but a careful assessment of the upper limits of geologic changes that could take place in the repository area over the next hundred thousand years. If waste containment were to survive these extreme geological changes the disposal site could be considered acceptable. If some release of activity were to take place in consequence of the hypothetical events the disposal solution might still be

Geology and Geochemistry of some crystalline basement rocks in ilesha area, southwestern nigeria: implications on provenance and evolution

International Nuclear Information System (INIS)

Oyinloye, A.O.

2007-01-01

Geological and geochemical study of the basement complex rocks in ilesha schist belt revealed that amphibolite, hornblende gneiss and granite gneiss are the major constituents. The gneisses are composed of similar rock forming silicates with variations in abundance. The amphibolite being a mafic rock has different compositions, containing abundant pyroxene, actinolite and tremolite. Monazite is present in the mineralogy of all these rocks. Chemical composition of these rocks revealed that they are petrogenetically related. Geochemical diagrams, plotted from chemical composition of these rocks, REE fractionation trends and presence of monazite in their mineralogy reveal that all these rocks were derived from a mixed magma source which did not originate from a pure tipper mantle, but possibly from a back arc tectonic setting. The pattern of the REE, progressively increasing negative Eu/Eu anomaly, La/sub N//Yb/sub N/ from the amphibolite to the granite gneiss and marked Eu depletion tend to implicate evolution through fractionation of a mixed basaltic magma to form the precursor of these rocks. The amphibolite probably represents the sample of the original basaltic magma. (author)

Geology of Mars after the first 40 years of exploration

International Nuclear Information System (INIS)

Rossi, Angelo Pio; Van Gasselt, Stephan

2010-01-01

The knowledge of Martian geology has increased enormously in the last 40 yr. Several missions orbiting or roving Mars have revolutionized our understanding of its evolution and geological features, which in several ways are similar to Earth, but are extremely different in many respects. The impressive dichotomy between the two Martian hemispheres is most likely linked to its impact cratering history, rather than internal dynamics such as on Earth. Mars' volcanism has been extensive, very long-lived and rather constant in its setting. Water was available in large quantities in the distant past of Mars, when a magnetic field and more vigorous tectonics were active. Exogenic forces have been shaping Martian landscapes and have led to a plethora of landscapes shaped by wind, water and ice. Mars' dynamical behavior continues, with its climatic variation affecting climate and geology until very recent times. This paper tries to summarize major highlights in Mars' Geology, and points to deeper and more extensive sources of important scientific contributions and future exploration. (invited reviews)

Palaeoclimate dynamics : a voyage through scales

Science.gov (United States)

Crucifix, Michel; Mitsui, Takahito

2015-04-01

Our knowledge of climate dynamics depends on indirect observations of past climate evolution, as well as on what can be inferred from theoretical arguments. At the scale of the Cenozoic, it is common to define a framework of nested time scales, the longest time scale of interest being related to the slow tectonic evolution, then variability associated with or controlled by the astronomical forcing, and finally the fastest dynamics associated with the natural modes of variability of the ocean and the atmosphere. For example, in a model, the astronomical modes of variability may be simulated with deterministic equations under fixed boundary conditions representing the tectonic state, and associated with stochastic parameterisations of the ocean-atmosphere (chaotic) modes of motion. Bifurcations or, more generally, qualitative changes in climate dynamics may be scanned by changing slowly the tectonic state, in order to provide explanations to observed changes in regimes such as the appearance of ice ages and their changes in length or amplitude. The above framework, largely theorized by B. Saltzman, may still be partly justified but is in need of a review. We address here specifically three questions: To what extent astronomical variability interacts with natural modes of ocean - atmosphere variability ? Specifically, how does millennial variability (e.g.: Dansgaard-Oeschger events) fit the Saltzman scheme ? The astronomical forcing is quasi-periodic, and we recently showed that it may produce somewhat counter-intuitive dynamics associated with the emergence of strange non-chaotic attractors. What are the consequences on the spectrum of climate variability ? What are the effects of centennial climate variability on the slow variability of climate ? These three questions are addressed by reference to recently published material, with the objective of emphasising research questions to be explored in the near future.

Geodiversity: Exploration of 3D geological model space

Science.gov (United States)

Lindsay, M. D.; Jessell, M. W.; Ailleres, L.; Perrouty, S.; de Kemp, E.; Betts, P. G.

2013-05-01

The process of building a 3D model necessitates the reconciliation of field observations, geophysical interpretation, geological data uncertainty and the prevailing tectonic evolution hypotheses and interpretations. Uncertainty is compounded when clustered data points collected at local scales are statistically upscaled to one or two points for use in regional models. Interpretation is required to interpolate between sparse field data points using ambiguous geophysical data in covered terranes. It becomes clear that multiple interpretations are possible during model construction. The various interpretations are considered as potential natural representatives, but pragmatism typically dictates that just a single interpretation is offered by the modelling process. Uncertainties are introduced into the 3D model during construction from a variety of sources and through data set optimisation that produces a single model. Practices such as these are likely to result in a model that does not adequately represent the target geology. A set of geometrical ‘geodiversity’ metrics are used to analyse a 3D model of the Gippsland Basin, southeastern Australia after perturbing geological input data via uncertainty simulation. The resulting sets of perturbed geological observations are used to calculate a suite of geological 3D models that display a range of geological architectures. The concept of biodiversity has been adapted for the geosciences to quantify geometric variability, or geodiversity, between models in order to understand the effect uncertainty has models geometry. Various geometrical relationships (depth, volume, contact surface area, curvature and geological complexity) are used to describe the range of possibilities exhibited throughout the model suite. End-member models geodiversity metrics are classified in a similar manner to taxonomic descriptions. Further analysis of the model suite is performed using principal component analysis (PCA) to determine

Viruses as new agents of organomineralization in the geological record.

Science.gov (United States)

Pacton, Muriel; Wacey, David; Corinaldesi, Cinzia; Tangherlini, Michael; Kilburn, Matt R; Gorin, Georges E; Danovaro, Roberto; Vasconcelos, Crisogono

2014-07-03

Viruses are the most abundant biological entities throughout marine and terrestrial ecosystems, but little is known about virus-mineral interactions or the potential for virus preservation in the geological record. Here we use contextual metagenomic data and microscopic analyses to show that viruses occur in high diversity within a modern lacustrine microbial mat, and vastly outnumber prokaryotes and other components of the microbial mat. Experimental data reveal that mineral precipitation takes place directly on free viruses and, as a result of viral infections, on cell debris resulting from cell lysis. Viruses are initially permineralized by amorphous magnesium silicates, which then alter to magnesium carbonate nanospheres of ~80-200 nm in diameter during diagenesis. Our findings open up the possibility to investigate the evolution and geological history of viruses and their role in organomineralization, as well as providing an alternative explanation for enigmatic carbonate nanospheres previously observed in the geological record.

Geology for a changing world 2010-2020-Implementing the U.S. Geological Survey science strategy

Science.gov (United States)

Gundersen, Linda C.S.; Belnap, Jayne; Goldhaber, Martin; Goldstein, Arthur; Haeussler, Peter J.; Ingebritsen, S.E.; Jones, John W.; Plumlee, Geoffrey S.; Thieler, E. Robert; Thompson, Robert S.; Back, Judith M.

2011-01-01

This report describes a science strategy for the geologic activities of the U.S. Geological Survey (USGS) for the years 2010-2020. It presents six goals with accompanying strategic actions and products that implement the science directions of USGS Circular 1309, 'Facing Tomorrow's Challenges-U.S. Geological Survey Science in the Decade 2007-2017.' These six goals focus on providing the geologic underpinning needed to wisely use our natural resources, understand and mitigate hazards and environmental change, and understand the relationship between humans and the environment. The goals emphasize the critical role of the USGS in providing long-term research, monitoring, and assessments for the Nation and the world. Further, they describe measures that must be undertaken to ensure geologic expertise and knowledge for the future. The natural science issues facing today's world are complex and cut across many scientific disciplines. The Earth is a system in which atmosphere, oceans, land, and life are all connected. Rocks and soils contain the answers to important questions about the origin of energy and mineral resources, the evolution of life, climate change, natural hazards, ecosystem structures and functions, and the movements of nutrients and toxicants. The science of geology has the power to help us understand the processes that link the physical and biological world so that we can model and forecast changes in the system. Ensuring the success of this strategy will require integration of geological knowledge with the other natural sciences and extensive collaboration across USGS science centers and with partners in Federal, State, and local agencies, academia, industry, nongovernmental organizations and, most importantly, the American public. The first four goals of this report describe the scientific issues facing society in the next 10 years and the actions and products needed to respond to these issues. The final two goals focus on the expertise and

A BRIEF NOTE ON MINERAL EVOLUTION AND BIOCHEMISTRY

Directory of Open Access Journals (Sweden)

José María Amigó

2014-12-01

Full Text Available The natural inorganic materials (minerals and rocks exceed the limits of the Earth.Therefore, the geology, which is the study of the Earth, represents only a small part of thenatural inorganic world. Certain questions about the genesis of the universe are related tothe evolution of our solar system and the evolution of life on our planet. In this paper, recentcontributions from experimental physical natural-sciences to the formation of the universe(about 15 billion BP coupled with the occurrence of minerals (4 million years BP and thebiochemical appearance of life (not more than 3 million years on the Earth are discussed.When Earth was formed, none of the more than 4,400 minerals we know today were existed.Cosmologists estimate that nearly ten billion years after the Big Bang the first elementsproduced by the melting process. The geological history of mineral evolution on the Earthis an interesting tool to study terrestrial and/or extraterrestrial mineralogy in regard toastronomy, biology, chemistry and other experimental natural sciences

Geologic environmental study

International Nuclear Information System (INIS)

Kim, Chun Soo; Bae, Dae Seok; Kim, Kyung Su; Park, Byung Yoon; Koh, Young Kown; Chun, Kwan Sik; Kim, Jhin Wung

2000-05-01

The geoscience research works are focused on the production of geologic basic data accompanying with the technical development of geology and hydrogeologic characterization. The lithology of the Korean peninsula consists of a complex structure of 29 rock types from Archean to Quaternary. The wide distribution of Mesozoic plutonic rock is an important consideration as a potential host rock allowing flexibility of siting. The recent tectonic activities are limited to localized particular area, which can be avoided by excluding in the early stage of siting. Three rock types such as plutonic rocks, crystalline gneisses and massive volcanic rocks were suggested as the preferred host rocks for the further study on HLW disposal system. This report contains grouping of regional faults, and on the distributional characteristics of faults and fractures(zones) in terms of lithological domain and tectonical provinces. The regional groundwater regime can be grouped into 3 regimes by tectonic setting and four groundwater regions based on an altitute. Groundwaters can be grouped by their chemistry and host rocks. The origin of groundwater was proposed by isotope ( 1 8O, 2 H, 1 3C, 3 4S, 8 7Sr, 1 5N) studies and the residence time of groundwater was inferred from their tritium contents. Based on the geochemical and isotope characteristics, the geochemical evolutions of each types of groundwater were simulated using SOLVEQ/CHILLER and PHREEQC programs

Considering timescales in the post-closure safety of geological disposal of radioactive waste

International Nuclear Information System (INIS)

2009-01-01

A key challenge in the development of safety cases for the deep geological disposal of radioactive waste is handling the long time frame over which the radioactive waste remains hazardous. The intrinsic hazard of the waste decreases with time, but some hazard remains for extremely long periods. Safety cases for geological disposal typically address performance and protection for thousands to millions of years into the future. Over such periods, a wide range of events and processes operating over many different timescales may impact on a repository and its environment. Uncertainties in the predictability of such factors increase with time, making it increasingly difficult to provide definite assurances of a repository's performance and the protection it may provide over longer timescales. Timescales, the level of protection and the assurance of safety are all linked. Approaches to handling timescales for the geological disposal of radioactive waste are influenced by ethical principles, the evolution of the hazard over time, uncertainties in the evolution of the disposal system (and how these uncertainties themselves evolve) and the stability and predictability of the geological environment. Conversely, the approach to handling timescales can affect aspects of repository planning and implementation including regulatory requirements, siting decisions, repository design, the development and presentation of safety cases and the planning of pre- and post-closure institutional controls such as monitoring requirements. This is an area still under discussion among NEA member countries. This report reviews the current status and ongoing discussions of this issue. (author)

Synthesis on the spent fuel long term evolution

Energy Technology Data Exchange (ETDEWEB)

Ferry, C.; Poinssot, Ch.; Lovera, P.; Poulesquen, A. [CEA Saclay, Dept. de Physico-Chimie (DEN/DPC), 91 - Gif sur Yvette (France); Broudic, V. [CEA Cadarache, Direction des Reacteurs Nucleaires (DRN), 13 - Saint Paul lez Durance (France); Cappelaere, Ch. [CEA Saclay, Dept. des Materiaux pour le Nucleaire(DMN), 91 - Gif-sur-Yvette (France); Desgranges, L. [CEA Cadarache, Direction des Reacteurs Nucleaires (DRN), 13 - Saint-Paul-lez-Durance (France); Garcia, Ph. [CEA Cadarache, Dept. d' Etudes des Combustibles (DEC), 13 - Saint Paul lez Durance (France); Jegou, Ch.; Roudil, D. [CEA Valrho, Dir. de l' Energie Nucleaire (DEN), 30 - Marcoule (France); Lovera, P.; Poulesquen, A. [CEA Saclay, Dept. de Physico-Chimie (DPC), 91 - Gif sur Yvette (France); Marimbeau, P. [CEA Cadarache, Dir. de l' Energie Nucleaire (DEN), 13 - Saint-Paul-lez-Durance (France); Gras, J.M.; Bouffioux, P. [Electricite de France (EDF), 75 - Paris (France)

2005-07-01

The French research on spent fuel long term evolution has been performed by CEA (Commissariat a l'Energie Atomique) since 1999 in the PRECCI project with the support of EDF (Electricite de France). These studies focused on the spent fuel behaviour under various conditions encountered in dry storage or in deep geological disposal. Three main types of conditions were discerned: - The evolution in a closed system which corresponds to the normal scenario in storage and to the first confinement phase in disposal; - The evolution in air which corresponds to an incidental loss of confinement during storage or to a rupture of the canister before the site re-saturation in geological disposal; - The evolution in water which corresponds to the normal scenario after the breaching of the canister in repository conditions. This document produced in the frame of the PRECCI project is an overview of the state of knowledge in 2004 concerning the long-term behavior of spent fuel under these various conditions. The state of the art was derived from the results obtained under the PRECCI project as well as from a review of the literature and of data acquired under the European project on Spent Fuel Stability under Repository Conditions. The main results issued from the French research are underlined. (authors)

Synthesis on the spent fuel long term evolution

International Nuclear Information System (INIS)

Ferry, C.; Poinssot, Ch.; Lovera, P.; Poulesquen, A.; Broudic, V.; Cappelaere, Ch.; Desgranges, L.; Garcia, Ph.; Jegou, Ch.; Roudil, D.; Lovera, P.; Poulesquen, A.; Marimbeau, P.; Gras, J.M.; Bouffioux, P.

2005-01-01

The French research on spent fuel long term evolution has been performed by CEA (Commissariat a l'Energie Atomique) since 1999 in the PRECCI project with the support of EDF (Electricite de France). These studies focused on the spent fuel behaviour under various conditions encountered in dry storage or in deep geological disposal. Three main types of conditions were discerned: - The evolution in a closed system which corresponds to the normal scenario in storage and to the first confinement phase in disposal; - The evolution in air which corresponds to an incidental loss of confinement during storage or to a rupture of the canister before the site re-saturation in geological disposal; - The evolution in water which corresponds to the normal scenario after the breaching of the canister in repository conditions. This document produced in the frame of the PRECCI project is an overview of the state of knowledge in 2004 concerning the long-term behavior of spent fuel under these various conditions. The state of the art was derived from the results obtained under the PRECCI project as well as from a review of the literature and of data acquired under the European project on Spent Fuel Stability under Repository Conditions. The main results issued from the French research are underlined. (authors)

Biosilicification Drives a Decline of Dissolved Si in the Oceans through Geologic Time

Directory of Open Access Journals (Sweden)

Daniel J. Conley

2017-12-01

Full Text Available Biosilicification has driven variation in the global Si cycle over geologic time. The evolution of different eukaryotic lineages that convert dissolved Si (DSi into mineralized structures (higher plants, siliceous sponges, radiolarians, and diatoms has driven a secular decrease in DSi in the global ocean leading to the low DSi concentrations seen today. Recent studies, however, have questioned the timing previously proposed for the DSi decreases and the concentration changes through deep time, which would have major implications for the cycling of carbon and other key nutrients in the ocean. Here, we combine relevant genomic data with geological data and present new hypotheses regarding the impact of the evolution of biosilicifying organisms on the DSi inventory of the oceans throughout deep time. Although there is no fossil evidence for true silica biomineralization until the late Precambrian, the timing of the evolution of silica transporter genes suggests that bacterial silicon-related metabolism has been present in the oceans since the Archean with eukaryotic silicon metabolism already occurring in the Neoproterozoic. We hypothesize that biological processes have influenced oceanic DSi concentrations since the beginning of oxygenic photosynthesis.

Coal Age Galapogos: Joggins and the lions of nineteenth century geology

Energy Technology Data Exchange (ETDEWEB)

Calder, J.H. [Nova Scotia Department of Natural Resources, Halifax, NS (Canada)

2006-07-01

Since the 1870s, the Joggins coastal section has been recognized as an outstanding section of Carboniferous strata. Accounts about the geology of the Joggins area first appeared in the published literature in 1828. Early history, visits by Sir Charles Lyell and Sir William Logan in 1842 and later, early Geological Survey of Canada field projects, tree trunk fauna, O.C. Marsh's fossil discoveries, Lyell, Dawson and Darwin on evolution, the origin of coal, and discoveries by Sir William Dawson are discussed. The Joggins coastal section has been placed on Canada's Tentative List of future World Heritage Site nominees. 71 refs., 18 figs.

(ajst) structural evolution of bode saadu area

African Journals Online (AJOL)

opiyo

2, pp. 17-24. STRUCTURAL EVOLUTION OF BODE SAADU AREA,. SOUTHWESTERN NIGERIA. C. T. Okonkwo. Department of Geology, University of Ilorin P.M.B. 1515, Ilorin, Nigeria. E-mail cokonkwo@unilorin.edu.ng. ABSTRACT: The Bode Saadu area comprises metasedimentary and metaigneous rocks which have.

Study on the remote sensing geological information of uranium mineralization in Western Liaoning and Northern Hebei

International Nuclear Information System (INIS)

Yu Baoshan; Wang Dianbai; Jin Shihua; Qiao Rui

1996-01-01

Based on the whole areal geological map joint application rd exploitation, composite forming map, generalization analysis and field examination in detail of key region that mainly depend on remote sensing information and generalize the data of geology, geophysical and geochemical prospecting, and geohydrology, this paper reveals the structure framework, regional geological background, uranium metallogenic condition and space time distribution rule of orustal evolution and its result, and set up the interpretation marks of arc-shaped structure in different of rock area and discusses its geological genesis. The author also interprets volcanic apparatus, small type closed sedimentary basin, magmatic rock body which relate closely to uranium deposit, ore control structure and occurrence and type of mineralization alteration envelope. The thermal halo point of satellite image is emphatically interpreted and its geological meaning and its relation to uranium deposit is discussed. Remote sensing geological prospecting ore model and synthetic provision model is determined lastly

Deep storage of radioactive waste from a geological point of view

International Nuclear Information System (INIS)

Venzlaff, Helmut

2015-01-01

For a deep storage of radioactive waste geologists gave their preference to salt prior to other rock complexes such as clay or granite. Major deposits from pure rock salt are particularly suitable to safely seal radioactive wastes from the biosphere because due to their plasticity they are free from fissures in which liquids and gases could circulate and because their thermal conductivity is higher than of other rocks. The geological stability of salt domes can be shown by their geological evolution. Thus the salt dome in Gorleben was formed 100 million years ago and is older than the Atlantic, the Alps or the ascent of the low mountain range. During this long period it survived ocean floods, mountain formations, earthquakes, volcanism and ice ages without considerably changing its shape. There are no geological reasons, why it should not remain stable during the next million years.

Deep storage of radioactive waste from a geological point of view

Energy Technology Data Exchange (ETDEWEB)

Venzlaff, Helmut [Federal Institute for Geo-Sciences and Raw Materials, Hannover (Germany)

2015-08-15

For a deep storage of radioactive waste geologists gave their preference to salt prior to other rock complexes such as clay or granite. Major deposits from pure rock salt are particularly suitable to safely seal radioactive wastes from the biosphere because due to their plasticity they are free from fissures in which liquids and gases could circulate and because their thermal conductivity is higher than of other rocks. The geological stability of salt domes can be shown by their geological evolution. Thus the salt dome in Gorleben was formed 100 million years ago and is older than the Atlantic, the Alps or the ascent of the low mountain range. During this long period it survived ocean floods, mountain formations, earthquakes, volcanism and ice ages without considerably changing its shape. There are no geological reasons, why it should not remain stable during the next million years.

California Geological Survey Geologic Map Index

Data.gov (United States)

California Natural Resource Agency — All the individual maps from the Geologic Atlas of California and the Regional Geologic map series have been georeferenced for display in a GIS (and viewable online...

Developing, choosing and using landscape evolution models to inform field-based landscape reconstruction studies : Developing, choosing and using landscape evolution models

NARCIS (Netherlands)

Temme, A.j.a.m.; Armitage, J.; Attal, M.; Van Gorp, W.; Coulthard, T.j.; Schoorl, J.m.

2017-01-01

Landscape evolution models (LEMs) are an increasingly popular resource for geomorphologists as they can operate as virtual laboratories where the implications of hypotheses about processes over human to geological timescales can be visualized at spatial scales from catchments to mountain ranges.

Major geological events and uranium metallogenesis in South-west China

International Nuclear Information System (INIS)

Zhang Chengjiang; Xu Zhengqi; Ni Shijun; Chen Youliang

2012-01-01

Uranium is widely distributed in South-west China, with all types but on a not-so-large scale. South-west China is located on the combining site of several large tectonic elements and every tectonic movement has different effects on different regions. To study and clarify the correlation between the major geological events in South-west China and the Uranium metallogenesis, comprehensive research and field investigation are made besides collecting a lot of materials. Through analysis and research on the major geological events in South-west China, the evolution of those e vents is basically clarified and the events closely related with uranium mineralization are determined. It is discovered that there are several ore-forming geologic events in the geological history of South-west China; almost every major tectonic movement cycle is accompanied with uranium metallogenesis, from Jinning Movement to Chengjiang Movement, to Hercynian Movement, to Indosinian Movement. to Yanshan Movement. to Himalayan movement. Even though every major tectonic cycle is accompanied with uranium mineralization, three major geological events are generally obviously related with uranium metallogenesis, i.e. the Rodinian supercontinent breakup even in Jinning-Chengjiang Period, Yanshan Movement and Himalayan movement, in which the first one is the process of uranium pre-enrichment and provides the source of uranium. Yanshan Movement and Himalayan movement are the important processes for mineralization, mainly the hydrothermal superimposed mineralization. (authors)

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

A geological history of reflecting optics.

Science.gov (United States)

Parker, Andrew Richard

2005-03-22

Optical reflectors in animals are diverse and ancient. The first image-forming eye appeared around 543 million years ago. This introduced vision as a selection pressure in the evolution of animals, and consequently the evolution of adapted optical devices. The earliest known optical reflectors--diffraction gratings--are 515 Myr old. The subsequent fossil record preserves multilayer reflectors, including liquid crystals and mirrors, 'white' and 'blue' scattering structures, antireflective surfaces and the very latest addition to optical physics--photonic crystals. The aim of this article is to reveal the diversity of reflecting optics in nature, introducing the first appearance of some reflector types as they appear in the fossil record as it stands (which includes many new records) and backdating others in geological time through evolutionary analyses. This article also reveals the commercial potential for these optical devices, in terms of lessons from their nano-level designs and the possible emulation of their engineering processes--molecular self-assembly.

The development and evolution of landform based on neotectonic ...

Indian Academy of Sciences (India)

Lingmin Zhong

2018-02-14

Feb 14, 2018 ... involving integration of data from the aspects of structural geology ... regions is very sensitive to crustal movement such as folding and faulting ...... drainage network evolution in the upper Narmada Valley: Implication to ...

Evolution and Adaptation of Phytoplankton Photosynthetic Pathways to perturbations of the geological carbon system

Science.gov (United States)

Rickaby, R. E.; Young, J. N.; Hermoso, M.; Heureux, A.; McCLelland, H.; Lee, R.; Eason Hubbard, M.

2012-12-01

The ocean and atmosphere carbon system has varied greatly over geological history both in response to initial evolutionary innovation, and as a driver of adaptive change. Here we establish that positive selection in Rubisco, the most abundant enzyme on the Earth responsible for all photosynthetic carbon fixation, occurred early in Earth's history, and basal to the radiation of the modern marine algal groups. Our signals of positive selection appear to be triggered by changing intracellular concentrations of carbon dioxide (CO2) due to the emergence of carbon concentrating mechanisms between 1.56 and 0.41 Ba in response to declining atmospheric CO2 . We contend that, at least in terms of carbon, phytoplankton generally were well poised to manage subsequent abrupt carbon cycle perturbations. The physiological pathways for optimising carbon acquisition across a wide range of ambient carbon dioxide concentrations had already been established and were genetically widespread across open ocean phytoplankton groups. We will further investigate some case studies from the Mesozoic and Cenozoic abrupt carbon cycle excursions using isotopic tools to probe the community photosynthetic response and demonstrate the flexibility of phytoplankton photosynthesis in the face of major perturbations. In particular, an unprecedented resolution record across the Toarcian (Early Jurassic) carbon isotope excursion in the Paris Basin reveals a selection and evolution towards a community reliant solely on diffusive carbon dioxide supply for photosynthesis at the height of the excursion at 1500-2500 ppm CO2. The continued flourishing of the phytoplankton biological pump throughout this excursion was able to remove the excess carbon injected into the water column in less than 45 kyrs.

Geological research for public outreach and education in Lithuania

Science.gov (United States)

Skridlaite, Grazina; Guobyte, Rimante

2013-04-01

Successful IYPE activities and implementation of Geoheritage day in Lithuania increased public awareness in geology. A series of projects introducing geology to the general public and youth, supported by EU funds and local communities, were initiated. Researchers from the scientific and applied geology institutions of Lithuania participated in these projects and provided with the geological data. In one case, the Lithuanian Survey of Protected Areas supported the installation of a series of geological exhibitions in several regional and national parks. An animation demonstrating glacial processes was chosen for most of these because the Lithuanian surface is largely covered with sedimentary deposits of the Nemunas (Weichselian) glaciation. Researchers from the Lithuanian Geological Survey used the mapping results to demonstrate real glacial processes for every chosen area. In another case, 3D models showing underground structures of different localities were based on detailed geological maps and profiles obtained for that area. In case of the Sartai regional park, the results of previous geological research projects provided the possibility to create a movie depicting the ca. 2 Ga geological evolution of the region. The movie starts with the accretion of volcanic island arcs on the earlier continental margin at ca. 2 Ga and deciphers later Precambrian tectonic and magmatic events. The reconstruction is based on numerous scientific articles and interpretation of geophysical data. Later Paleozoic activities and following erosion sculptured the surface which was covered with several ice sheets in Quaternary. For educational purpose, a collection of minerals and rocks at the Forestry Institute was used to create an exhibition called "Cycle of geological processes". Forestry scientists and their students are able to study the interactions of geodiversity and biodiversity and to understand ancient and modern geological processes leading to a soil formation. An aging

Uranium geochemistry, mineralogy, geology, exploration and resources

International Nuclear Information System (INIS)

De Vivo, B.

1984-01-01

This book comprises papers on the following topics: history of radioactivity; uranium in mantle processes; transport and deposition of uranium in hydrothermal systems at temperatures up to 300 0 C: Geological implications; geochemical behaviour of uranium in the supergene environment; uranium exploration techniques; uranium mineralogy; time, crustal evolution and generation of uranium deposits; uranium exploration; geochemistry of uranium in the hydrographic network; uranium deposits of the world, excluding Europe; uranium deposits in Europe; uranium in the economics of energy; role of high heat production granites in uranium province formation; and uranium deposits

Geologic Mapping, Volcanic Stages and Magmatic Processes in Hawaiian Volcanoes

Science.gov (United States)

Sinton, J. M.

2005-12-01

The concept of volcanic stages arose from geologic mapping of Hawaiian volcanoes. Subaerial Hawaiian lava successions can be divided generally into three constructional phases: an early (shield) stage dominated by thin-bedded basaltic lava flows commonly associated with a caldera; a later (postshield) stage with much thicker bedded, generally lighter colored lava flows commonly containing clinopyroxene; calderas are absent in this later stage. Following periods of quiescence of a half million years or more, some Hawaiian volcanoes have experienced renewed (rejuvenated) volcanism. Geological and petrographic relations irrespective of chemical composition led to the identification of mappable units on Niihau, Kauai, Oahu, Molokai, Maui and Hawaii, which form the basis for this 3-fold division of volcanic activity. Chemical data have complicated the picture. There is a growing tendency to assign volcanic stage based on lava chemistry, principally alkalicity, into tholeiitic shield, alkalic postshield, and silica undersaturated rejuvenation, despite the evidence for interbedded tholeiitic and alkalic basalts in many shield formations, and the presence of mildly tholeiitic lavas in some postshield and rejuvenation formations. A consistent characteristic of lava compositions from most postshield formations is evidence for post-melting evolution at moderately high pressures (3-7 kb). Thus, the mapped shield to postshield transitions primarily reflect the disappearance of shallow magma chambers (and associated calderas) in Hawaiian volcanoes, not the earlier (~100 ka earlier in Waianae Volcano) decline in partial melting that leads to the formation of alkalic parental magmas. Petrological signatures of high-pressure evolution are high-temperature crystallization of clinopyroxene and delayed crystallization of plagioclase, commonly to <3 % MgO. Petrologic modeling using pMELTS and MELTS algorithms allows for quantification of the melting and fractionation conditions giving

A combined rigid/deformable plate tectonic model for the evolution of the Indian Ocean

Science.gov (United States)

Watson, J. G.; Glover, C. T.; Adriasola Munoz, A. C.; Harris, J. P.; Goodrich, M.

2012-04-01

Plate tectonic reconstructions are essential for placing geological information in its correct spatial context, understanding depositional environments, defining basin dimensions and evolution, and serve as a basis for palaeogeographic mapping and for palaeo-climate modelling. Traditional 'rigid' plate reconstructions often result in misfits (overlaps and underfits) in the geometries of juxtaposed plate margins when restored to their pre-rift positions. This has been attributed to internal deformation pre- and/or syn- continental break-up. Poorly defined continent-ocean boundaries add to these problems. To date, few studies have integrated continental extension within a global model. Recent plate tectonic reconstructions based on the relative motions of Africa, Madagascar, India and Antarctica during the break-up of eastern Gondwana have not taken into account the effects of deformation; particularly between India and Madagascar, and India and the Seychelles. A deformable plate model is in development that builds on the current rigid plate model to describe the complex multiphase break-up history between Africa, Madagascar, Seychelles and India, the associated magmatic activity and subsequent India/Eurasia collision. The break-up of eastern Gondwana occurred in the mid Jurassic by rifting between Africa and the India-Madagascar-Australian-Antarctica plates, followed by the Late Jurassic drift of India away from Australia and the Cretaceous break-up of Australia and Antarctica. The northwards drift of the Seychelles-India block in the Tertiary was accommodated by the opening of the Laxmi Basin. This was followed by the eruption of the extensive Deccan flood basalts and the separation of India and the Seychelles. Crustal domains on volcanic margins can be very difficult to define due to the accretion of magmatic material. On these margins, there is much speculation on the position of the continent-ocean boundary and the timing of rifting and sea-floor spreading. The

Geologic environmental study

Energy Technology Data Exchange (ETDEWEB)

Kim, Chun Soo; Bae, Dae Seok; Kim, Kyung Su; Park, Byung Yoon; Koh, Young Kown; Chun, Kwan Sik; Kim, Jhin Wung

2000-05-01

The geoscience research works are focused on the production of geologic basic data accompanying with the technical development of geology and hydrogeologic characterization. The lithology of the Korean peninsula consists of a complex structure of 29 rock types from Archean to Quaternary. The wide distribution of Mesozoic plutonic rock is an important consideration as a potential host rock allowing flexibility of siting. The recent tectonic activities are limited to localized particular area, which can be avoided by excluding in the early stage of siting. Three rock types such as plutonic rocks, crystalline gneisses and massive volcanic rocks were suggested as the preferred host rocks for the further study on HLW disposal system. This report contains grouping of regional faults, and on the distributional characteristics of faults and fractures(zones) in terms of lithological domain and tectonical provinces. The regional groundwater regime can be grouped into 3 regimes by tectonic setting and four groundwater regions based on an altitute. Groundwaters can be grouped by their chemistry and host rocks. The origin of groundwater was proposed by isotope ({sup 1}8O, {sup 2}H, {sup 1}3C, {sup 3}4S, {sup 8}7Sr, {sup 1}5N) studies and the residence time of groundwater was inferred from their tritium contents. Based on the geochemical and isotope characteristics, the geochemical evolutions of each types of groundwater were simulated using SOLVEQ/CHILLER and PHREEQC programs.

Origins of Sinuous and Braided Channels on Ascraeus Mons, Mars - A Keck Geology Consortium Undergraduate Research Project

Science.gov (United States)

de Wet, A. P.; Bleacher, J. E.; Garry, W. B.

2012-01-01

Water has clearly played an important part in the geological evolution of Mars. There are many features on Mars that were almost certainly formed by fluvial processes -- for example, the channels Kasei Valles and Ares Vallis in the Chryse Planitia area of Mars are almost certainly fluvial features. On the other hand, there are many channel features that are much more difficult to interpret -- and have been variously attributed to volcanic and fluvial processes. Clearly unraveling the details of the role of water on Mars is extremely important, especially in the context of the search of extinct or extant life. In this project we built on our recent work in determining the origin of one channel on the southwest rift apron of Ascraeus Mons. This project, funded by the Keck Geology Consortium and involving 4 undergraduate geology majors took advantage of the recently available datasets to map and analyze similar features on Ascraeus Mons and some other areas of Mars. A clearer understanding of how these particular channel features formed might lead to the development of better criteria to distinguish how other Martian channel features formed. Ultimately this might provide us with a better understanding of the role of volcanic and fluvial processes in the geological evolution of Mars.

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.

The deep geologic repository technology programme: toward a geoscience basis for understanding repository safety

International Nuclear Information System (INIS)

Jensen, M.R.

2007-01-01

Within the Deep Geologic Repository Technology Programme (DGRTP) several Geoscience activities are focused on advancing the understanding of groundwater flow system evolution and geochemical stability in a Canadian Shield setting as affected by long-term climate change. A key aspect is developing confidence in predictions of groundwater flow patterns and residence times as they relate to the safety of a deep geologic repository for used nuclear fuel waste. This is being achieved through a coordinated multi-disciplinary approach intent on: i) demonstrating coincidence between independent geo-scientific data; ii) improving the traceability of geo-scientific data and its interpretation within a conceptual descriptive model(s); iii) improving upon methods to assess and demonstrate robustness in flow domain prediction(s) given inherent flow domain uncertainties (i.e. spatial chemical/physical property distributions, boundary conditions) in time and space; and iv) improving awareness amongst geo-scientists as to the utility of various geo-scientific data in supporting a safety case for a deep geologic repository. This multi-disciplinary DGRTP approach is yielding an improved understanding of groundwater flow system evolution and stability in Canadian Shield settings that is further contributing to the geo-scientific basis for understanding and communicating aspects of DGR safety. (author)

Synthetic geology - Exploring the "what if?" in geology

Science.gov (United States)

Klump, J. F.; Robertson, J.

2015-12-01

The spatial and temporal extent of geological phenomena makes experiments in geology difficult to conduct, if not entirely impossible and collection of data is laborious and expensive - so expensive that most of the time we cannot test a hypothesis. The aim, in many cases, is to gather enough data to build a predictive geological model. Even in a mine, where data are abundant, a model remains incomplete because the information at the level of a blasting block is two orders of magnitude larger than the sample from a drill core, and we have to take measurement errors into account. So, what confidence can we have in a model based on sparse data, uncertainties and measurement error? Synthetic geology does not attempt to model the real world in terms of geological processes with all their uncertainties, rather it offers an artificial geological data source with fully known properties. On the basis of this artificial geology, we can simulate geological sampling by established or future technologies to study the resulting dataset. Conducting these experiments in silico removes the constraints of testing in the field or in production, and provides us with a known ground-truth against which the steps in a data analysis and integration workflow can be validated.Real-time simulation of data sources can be used to investigate crucial questions such as the potential information gain from future sensing capabilities, or from new sampling strategies, or the combination of both, and it enables us to test many "what if?" questions, both in geology and in data engineering. What would we be able to see if we could obtain data at higher resolution? How would real-time data analysis change sampling strategies? Does our data infrastructure handle many new real-time data streams? What feature engineering can be deducted for machine learning approaches? By providing a 'data sandbox' able to scale to realistic geological scenarios we hope to start answering some of these questions.

Scientific reference on the long time evolution of spent fuels; Referentiel scientifique sur l'evolution a long terme des combustibles uses

Energy Technology Data Exchange (ETDEWEB)

Ferry, C.; Poinssot, Ch.; Broudic, V.; Jegou, Ch.; Roudil, D.; Poulesquen, A.; Miserque, F. [CEA Saclay, Dept. de Physico-Chimie, 91 - Gif sur Yvette (France); Cappelaere, Ch. [CEA Saclay, Dept. des Materiaux pour le Nucleaire, 91 - Gif-sur-Yvette (France); Desgranges, L.; Garcia, Ph.; Piron, J.P. [CEA Cadarache, 13 - Saint-Paul-lez-Durance (France). Dept. d' Etudes des Combustibles; Lovera, P.; Marimbeau, P. [CEA Cadarache, 13 - Saint Paul lez Durance (France). Dept. d' Etudes des Reacteurs; Corbel, C. [CEA Saclay, Dept. de Recherche sur l' Etat Condense, les Atomes et les Molecules, 91 - Gif sur Yvette (France)

2005-03-15

This report is published in the framework of the 1991 French law for the nuclear waste management. The state of the art reported here concerns the long term evolution of spent fuel in the various environmental conditions corresponding to dry storage and geological disposal: closed system, air and water saturated medium. This review is based on the results of the french PRECCI project (Research Program on Long term Evolution of Spent Nuclear Fuel) and on literature data. (authors)

Onshore/ Offshore Geologic Assessment for Carbon Storage in the Southeastern United States

Science.gov (United States)

Knapp, C. C.; Knapp, J. H.; Brantley, D.; Lakshmi, V.; Almutairi, K.; Almayahi, D.; Akintunde, O. M.; Ollmann, J.

2017-12-01

Eighty percent of the world's energy relies on fossil fuels and under increasingly stricter national and international regulations on greenhouse gas emissions storage of CO2 in geologic repositories seems to be not only a feasible, but also and vital solution for near/ mid-term reduction of carbon emissions. We have evaluated the feasibility of CO2 storage in saline formations of the Eastern North American Margin (ENAM) including (1) the Jurassic/Triassic (J/TR) sandstones of the buried South Georgia Rift (SGR) basin, and (2) the Mesozoic and Cenozoic geologic formations along the Mid- and South Atlantic seaboard. These analyses have included integration of subsurface geophysical data (2- and 3-D seismic surveys) with core samples, well logs as well as uses of geological databases and geospatial analysis leading to CO2 injection simulation models. ENAM is a complex and regionally extensive mature Mesozoic passive margin rift system encompassing: (1) a large volume and regional extent of related magmatism known as the Central Atlantic Magmatic Province (CAMP), (2) a complete stratigraphic column that records the post-rift evolution in several basins, (3) preserved lithospheric-scale pre-rift structures including Paleozoic sutures, and (4) a wide range of geological, geochemical, and geophysical studies both onshore and offshore. While the target reservoirs onshore show heterogeneity and a highly complex geologic evolution they also show promising conditions for significant safe CO2 storage away from the underground acquifers. Our offshore study (the Southeast Offshore Storage Resource Assessment - SOSRA) is focused on the outer continental shelf from North Carolina to the southern tip of Florida. Three old exploration wells are available to provide additional constraints on the seismic reflection profiles. Two of these wells (TRANSCO 1005-1 and COST GE-1) penetrate the pre-rift Paleozoic sedimentary formations while the EXXON 564-1 well penetrates the post

Impacts of natural events and processes on groundwater flow conditions: a case study in the Horonobe Area, Hokkaido, Northern Japan

International Nuclear Information System (INIS)

Niizato, T.; Yasue, K.I.; Kurikami, H.

2009-01-01

In order to assess the long-term stability of the geological environments for over several hundred thousand years, it is important to consider the influence of natural events and processes, such as uplift, subsidence, denudation and climate change, on the geological environments, especially in an active region such as Japan. This study presents a conceptual model related to the future natural events and processes which have potential impacts on the groundwater flow conditions in the Horonobe area, Hokkaido, northern Japan on the basis of the neo-tectonics, palaeogeography, palaeo-climate, historical development of landform, and present state of groundwater flow conditions. We conclude that it is important to consider interactions among natural events and processes on the describing of the best-possible approximation of the time-variation of geological environment. (authors)

Structure and geological evolution of the bedrock at southern Satakunta, SW Finland

International Nuclear Information System (INIS)

Paulamaeki, S.; Paananen, M.; Elo, S.

2002-02-01

The southern Satakunta area lies on the west coast of Finland, mainly covering the mainland (with main towns Pori and Rauma), but also including the coastal archipelago and part of the Bothnian Sea. Near the centre of the area lies the island of Olkiluoto, on which Finland's site for a deep repository for spent nuclear fuel is located. The purpose of the present report is to compile and interpret all available geological and geophysical data relevant to understanding the regional geological setting of the Olkiluoto site. The area described is covered by four 1:100 000 scale geological map sheets, published by the Geological Survey of Finland, which, together with low-altitude aeromagnetic maps, provide the basis for a new 1:250 000 geological map compilation. This shows that the bedrock of southern Satakunta can be subdivided into three main zones: a pelitic migmatite belt in the southwest, a central, NW-SE trending area of sandstone, and a psammitic migmatite belt in the northeast. The migmatite belts formed during the Svecofennian orogeny, 1900-1800 Ma ago (Palaeoproterozoic). The sandstone area is the remnant of an alluvial basin, preserved now in a NW-SE trending graben, bounded on both sides by normal fault zones. The sandstones are thought to be at least 1400-1300 Ma old (Mesoproterozoic), and they are cut by Postjotnian olivine diabase dykes, 1270-1250 Ma in age. The Svecofennian migmatite belts show a complex history of formation, with various phases of anatexis/metamorphism, deformation and intrusion. In the pelitic migmatite belt, in which the Olkiluoto site is situated, four phases of ductile deformation (D-D4) and two phases of regional highT/lowP metamorphism and migmatite formation can be recognised, together with synorogenic (tonalite, granodiotite) and late orogenic ( potassium granite) intrusions. Subsequently, this very heterogeneous complex was intruded by anorogenic rapakivi granites, with ages 1580-1550 Ma. One pluton, the Eurajoki stock

Lunar Geologic Mapping: A Preliminary Map of a Portion of the LQ-10 ("Marius") Quadrangle

Science.gov (United States)

Gregg, T. K. P.; Yingst, R. A.

2009-01-01

Since the first lunar mapping program ended in the 1970s, new topographical, multispectral, elemental and albedo imaging datasets have become available (e.g., Clementine, Lunar Prospector, Galileo). Lunar science has also advanced within the intervening time period. A new systematic lunar geologic mapping effort endeavors to build on the success of earlier mapping programs by fully integrating the many disparate datasets using GIS software and bringing to bear the most current understanding of lunar geologic history. As part of this program, we report on a 1:2,500,000-scale preliminary map of a subset of Lunar Quadrangle 10 ("LQ-10" or the "Marius Quadrangle," see Figures 1 and 2), and discuss the first-order science results. By generating a geologic map of this region, we can constrain the stratigraphic and geologic relationships between features, revealing information about the Moon s chemical and thermal evolution.

Assessment of Environmental Factors of Geology on Waste and Engineering Barriers for Waste Storage Near Surface

International Nuclear Information System (INIS)

Arimuladi SP

2007-01-01

Geological environment factors include features and processes occurring within that spatial and temporal (post-closure) domain whose principal effect is to determine the evolution of the physical, chemical, biological and human conditions of the domain that are relevant to estimating the release and migration of radionuclide and consequent exposure to man. Hardness of radioactive waste and engineer barrier can be decrease by environmental factors. Disposal system domain geological environment factors is a category in the International FEP list and is divided into sub-categories. There are 13 sub-factors of geological environment, 12 sub-factors influence hardness of radioactive waste and engineer barrier, thermal processes and conditions in geosphere can be excluded. (author)

Relations between Vegetation and Geologic Framework in Barrier Island

Science.gov (United States)

Smart, N. H.; Ferguson, J. B.; Lehner, J. D.; Taylor, D.; Tuttle, L. F., II; Wernette, P. A.

2017-12-01

Barrier islands provide valuable ecosystems and protective services to coastal communities. The longevity of barrier islands is threatened by sea-level rise, human impacts, and extreme storms. The purpose of this research is to evaluate how vegetation dynamics interact with the subsurface and offshore framework geology to influence the beach and dune morphology. Beach and dune morphology can be viewed as free and/or forced behavior, where free systems are stochastic and the morphology is dependent on variations in the storm surge run-up, aeolian sediment supply and transport potential, and vegetation dynamics and persistence. Forced systems are those where patterns in the coastal morphology are determined by some other structural control, such as the underlying and offshore framework geology. Previous studies have documented the effects of geologic framework or vegetation dynamics on the beach and dunes, although none have examined possible control by vegetation dynamics in context of the geologic framework (i.e. combined free and forced behavior). Padre Island National Seashore (PAIS) was used to examine the interaction of free and forced morphology because the subsurface framework geology and surface beach and dune morphology are variable along the island. Vegetation dynamics were assessed by classifying geographically referenced historical aerial imagery into areas with vegetation and areas without vegetation, as well as LiDAR data to verify this imagery. The subsurface geologic structure was assessed using a combination of geophysical surveys (i.e. electromagnetic induction, ground-penetrating radar, and offshore seismic surveys). Comparison of the observed vegetation patterns and geologic framework leads to a series of questions surrounding how mechanistically these two drivers of coastal morphology are related. Upcoming coring and geophysical surveys will enable us to validate new and existing geophysical data. Results of this paper will help us better

Geological Evolution of the Ganiki Planitia Quadrangle (V14) on Venus

Science.gov (United States)

Grosfils, E. B.; Drury, D. E.; Hurwitz, D. M.; Kastl, B.; Long, s. M.; Richards, J. W.; Venechuk, E. M.

2005-01-01

The Ganiki Planitia quadrangle (25-50degN, 180-210degE) is located north of Atla Regio, south of Vinmara Planitia, and southeast of Atalanta Planitia. The region contains a diverse array of volcanic-, tectonic- and impact-derived features, and the objectives for the ongoing mapping effort are fivefold: 1) explore the formation and evolution of radiating dike swarms within the region, 2) use the diverse array of volcanic deposits to further test the neutral buoyancy hypothesis proposed to explain the origin of reservoir-derived features, 3&4) unravel the volcanic and tectonic evolution in this area, and 5) explore the implications of 1-4 for resurfacing mechanisms. Here we summarize our onging analysis of the material unit stratigraphy in the quadrangle, data central to meeting the aforementioned objectives successfully.

Confidence building in implementation of geological disposal

International Nuclear Information System (INIS)

Umeki, Hiroyuki

2004-01-01

Long-term safety of the disposal system should be demonstrated to the satisfaction of the stakeholders. Convincing arguments are therefore required that instil in the stakeholders confidence in the safety of a particular concept for the siting and design of a geological disposal, given the uncertainties that inevitably exist in its a priori description and in its evolution. The step-wise approach associated with making safety case at each stage is a key to building confidence in the repository development programme. This paper discusses aspects and issues on confidence building in the implementation of HLW disposal in Japan. (author)

Simulation of Anisotropic Rock Damage for Geologic Fracturing

Science.gov (United States)

Busetti, S.; Xu, H.; Arson, C. F.

2014-12-01

model to couple damage evolution with plasticity and with permeability for more geologically realistic simulation.

Structural Framework and Architecture of the Paleoproterozoic Bryah and Padbury Basins from Integrated Potential Field and Geological Datasets: Towards an Understanding of the Basin Evolution

Science.gov (United States)

Nigro R A Ramos, L.; Aitken, A.; Occhipinti, S.; Lindsay, M.

2017-12-01

The Bryah and Padbury Basins were developed along the northern margin of the Yilgarn Craton, in the southern portion of the Capricorn Orogen, which represents a Proterozoic tectonic zone that bounds the Yilgarn and Pilbara Cratons in Western Australia. These basins have been previously interpreted as developing in a rift, back-arc, and retro-arc foreland basins. Recent studies suggest that the Bryah Basin was deposited in a rift setting, while the overlying Padbury Basin evolved in a pro-foreland basin during the collision of the Yilgarn Craton and the Pilboyne block (formed by the Pilbara Craton and the Glenburgh Terrane), occurring in the Glenburgh Orogeny (2005-1960 Ma). This study focuses on characterizing the architecture and structural framework of the Bryah and Padbury Basins through analysis of geophysical and geological datasets, in order to better understand the different stages of the basins evolution. Gravity and magnetic data were used to define the main tectonic units and lithological boundaries, and to delineate major discontinuities in the upper and lower crust, as well as anomalies through a combination of map view interpretation and forward modelling. Geological mapping and drill core observations were linked with the geophysical interpretations. Fourteen magnetic domains are distinguished within the basins, while four main domains based on the Bouguer Anomaly are recognized. The highest gravity amplitude is related with an anomaly trending EW/NE-SW, which is coincident with the voluminous mafic rocks of the Bryah Basin, and may indicate the presence of an approximately 5km thick package of higher density mafic rocks. Magnetic depth estimations also indicate deep magnetic sources up to approximately 4,45km. These results can help to elucidate processes that occurred during the precursor rift of the early stages of the Bryah Basin, add information in relation to the basement control on sedimentation, allow the characterization of the varying

The Pilot Lunar Geologic Mapping Project: Summary Results and Recommendations from the Copernicus Quadrangle

Science.gov (United States)

Skinner, J. A., Jr.; Gaddis, L. R.; Hagerty, J. J.

2010-01-01

The first systematic lunar geologic maps were completed at 1:1M scale for the lunar near side during the 1960s using telescopic and Lunar Orbiter (LO) photographs [1-3]. The program under which these maps were completed established precedents for map base, scale, projection, and boundaries in order to avoid widely discrepant products. A variety of geologic maps were subsequently produced for various purposes, including 1:5M scale global maps [4-9] and large scale maps of high scientific interest (including the Apollo landing sites) [10]. Since that time, lunar science has benefitted from an abundance of surface information, including high resolution images and diverse compositional data sets, which have yielded a host of topical planetary investigations. The existing suite of lunar geologic maps and topical studies provide exceptional context in which to unravel the geologic history of the Moon. However, there has been no systematic approach to lunar geologic mapping since the flight of post-Apollo scientific orbiters. Geologic maps provide a spatial and temporal framework wherein observations can be reliably benchmarked and compared. As such, a lack of a systematic mapping program means that modern (post- Apollo) data sets, their scientific ramifications, and the lunar scientists who investigate these data, are all marginalized in regard to geologic mapping. Marginalization weakens the overall understanding of the geologic evolution of the Moon and unnecessarily partitions lunar research. To bridge these deficiencies, we began a pilot geologic mapping project in 2005 as a means to assess the interest, relevance, and technical methods required for a renewed lunar geologic mapping program [11]. Herein, we provide a summary of the pilot geologic mapping project, which focused on the geologic materials and stratigraphic relationships within the Copernicus quadrangle (0-30degN, 0-45degW).

Implications of S1 tephra findings in Dead Sea and Tayma palaeolake sediments for marine reservoir age estimation and palaeoclimate synchronisation

Science.gov (United States)

Neugebauer, Ina; Wulf, Sabine; Schwab, Markus J.; Serb, Johanna; Plessen, Birgit; Appelt, Oona; Brauer, Achim

2017-08-01

Here we report on the first findings of a cryptotephra in the Holocene lacustrine sediment records of the Dead Sea and Tayma palaeolake (NW Arabian Peninsula). The major element glass composition of this rhyolitic tephra is identical to the distal 'S1' tephra layer identified in the Yammoûneh palaeolake (Lebanon), in a marine sediment record from the SE Levantine basin and in the Sodmein Cave archaeological site in Egypt. The S1 tephra corresponds to the early Holocene 'Dikkartın' dome eruption of the Erciyes Dağ volcano in central Anatolia (Turkey) and has been dated in the marine record at 8830 ± 140 cal yr BP. We present new age estimates of the S1 tephra based on radiocarbon dating of terrestrial plant remains and pollen concentrates revealing ages of 8939 ± 83 cal yr BP in the Dead Sea sediments and 9041 ± 254 cal yr BP in Tayma. The precise date from the Dead Sea allows refining the early Holocene marine reservoir age in the SE Levantine Sea to ca. 320 ± 50 years. Synchronisation of marine and terrestrial palaeoclimate records in the eastern Mediterranean region using the S1 tephra further suggests a time-transgressive expansion of the early Holocene humid period.

Diffusion Dominant Solute Transport Modelling in Fractured Media Under Deep Geological Environment - 12211

Energy Technology Data Exchange (ETDEWEB)

Kwong, S. [National Nuclear Laboratory (United Kingdom); Jivkov, A.P. [Research Centre for Radwaste and Decommissioning and Modelling and Simulation Centre, University of Manchester (United Kingdom)

2012-07-01

Deep geologic disposal of high activity and long-lived radioactive waste is gaining increasing support in many countries, where suitable low permeability geological formation in combination with engineered barriers are used to provide long term waste contaminant and minimise the impacts to the environment and risk to the biosphere. This modelling study examines the solute transport in fractured media under low flow velocities that are relevant to a deep geological environment. In particular, reactive solute transport through fractured media is studied using a 2-D model, that considers advection and diffusion, to explore the coupled effects of kinetic and equilibrium chemical processes. The effects of water velocity in the fracture, matrix porosity and diffusion on solute transport are investigated and discussed. Some illustrative modelled results are presented to demonstrate the use of the model to examine the effects of media degradation on solute transport, under the influences of hydrogeological (diffusion dominant) and microbially mediated chemical processes. The challenges facing the prediction of long term degradation such as cracks evolution, interaction and coalescence are highlighted. The potential of a novel microstructure informed modelling approach to account for these effects is discussed, particularly with respect to investigating multiple phenomena impact on material performance. The GRM code is used to examine the effects of media degradation for a geological waste disposal package, under the combined hydrogeological (diffusion dominant) and chemical effects in low groundwater flow conditions that are typical of deep geological disposal systems. An illustrative reactive transport modelling application demonstrates the use of the code to examine the interplay of kinetic controlled biogeochemical reactive processes with advective and diffusive transport, under the influence of media degradation. The initial model results are encouraging which show the

The geological attitude

International Nuclear Information System (INIS)

Fuller, J.G.C.M.

1992-01-01

This paper discusses geological activity which takes place mainly in response to industrial and social pressures. Past geological reaction to these pressures profoundly altered popular conceptions of time, the Church, man, and the balance of nature. The present-day circumstances of geology are not essentially different from those of the past. Petroleum geology in North American illustrates the role of technology in determining the style and scope of geological work. Peaks of activity cluster obviously on the introduction from time to time of new instrumental capabilities (geophysical apparatus, for example), although not infrequently such activity is testing concepts or relationships perceived long before. Organic metamorphism and continental drift provide two examples. The petroleum industry now faces the dilemma of satisfying predicted demands for fuel, without doing irreparable injury to its environment of operation. Awareness of man's place in nature, which is a fundamental perception of geology, governs the geological attitude

Quantitative geological modeling based on probabilistic integration of geological and geophysical data

DEFF Research Database (Denmark)

Gulbrandsen, Mats Lundh

In order to obtain an adequate geological model of any kind, proper integration of geophysical data, borehole logs and geological expert knowledge is important. Geophysical data provide indirect information about geology, borehole logs provide sparse point wise direct information about geology...... entitled Smart Interpretation is developed. This semi-automatic method learns the relation between a set of data attributes extracted from deterministically inverted airborne electromagnetic data and a set of interpretations of a geological layer that is manually picked by a geological expert...

Structure and geological evolution of the bedrock at southern Satakunta, SW Finland

Energy Technology Data Exchange (ETDEWEB)

Paulamaeki, S.; Paananen, M.; Elo, S. [Geological Survey of Finland (Finland)

2002-02-01

The southern Satakunta area lies on the west coast of Finland, mainly covering the mainland (with main towns Pori and Rauma), but also including the coastal archipelago and part of the Bothnian Sea. Near the centre of the area lies the island of Olkiluoto, on which Finland's site for a deep repository for spent nuclear fuel is located. The purpose of the present report is to compile and interpret all available geological and geophysical data relevant to understanding the regional geological setting of the Olkiluoto site. The area described is covered by four 1:100 000 scale geological map sheets, published by the Geological Survey of Finland, which, together with low-altitude aeromagnetic maps, provide the basis for a new 1:250 000 geological map compilation. This shows that the bedrock of southern Satakunta can be subdivided into three main zones: a pelitic migmatite belt in the southwest, a central, NW-SE trending area of sandstone, and a psammitic migmatite belt in the northeast. The migmatite belts formed during the Svecofennian orogeny, 1900-1800 Ma ago (Palaeoproterozoic). The sandstone area is the remnant of an alluvial basin, preserved now in a NW-SE trending graben, bounded on both sides by normal fault zones. The sandstones are thought to be at least 1400-1300 Ma old (Mesoproterozoic), and they are cut by Postjotnian olivine diabase dykes, 1270-1250 Ma in age. The Svecofennian migmatite belts show a complex history of formation, with various phases of anatexis/metamorphism, deformation and intrusion. In the pelitic migmatite belt, in which the Olkiluoto site is situated, four phases of ductile deformation (D-D4) and two phases of regional highT/lowP metamorphism and migmatite formation can be recognised, together with synorogenic (tonalite, granodiotite) and late orogenic ( potassium granite) intrusions. Subsequently, this very heterogeneous complex was intruded by anorogenic rapakivi granites, with ages 1580-1550 Ma. One pluton, the Eurajoki stock

Terrestrial analogs, planetary geology, and the nature of geological reasoning

Science.gov (United States)

Baker, Victor R.

2014-05-01

Analogical reasoning is critical to planetary geology, but its role can be misconstrued by those unfamiliar with the practice of that science. The methodological importance of analogy to geology lies in the formulation of genetic hypotheses, an absolutely essential component of geological reasoning that was either ignored or denigrated by most 20th century philosophers of science, who took the theoretical/ experimental methodology of physics to be the sole model for all of scientific inquiry. Following the seminal 19th century work of Grove Karl Gilbert, an early pioneer of planetary geology, it has long been recognized that broad experience with and understanding of terrestrial geological phenomena provide geologists with their most effective resource for the invention of potentially fruitful, working hypotheses. The actions of (1) forming such hypotheses, (2) following their consequences, and (3) testing those consequences comprise integral parts of effective geological practice in regard to the understanding of planetary surfaces. Nevertheless, the logical terminology and philosophical bases for such practice will be unfamiliar to most planetary scientists, both geologists and nongeologists. The invention of geological hypotheses involves both inductive inferences of the type Gilbert termed “empiric classification” and abductive inferences of a logical form made famous by the 19th century American logician Charles Sanders Peirce. The testing and corroboration of geological hypotheses relies less on the correspondence logic of theoretical/ experimental sciences, like physics, and more on the logic of consistency, coherence, and consilience that characterizes the investigative and historical sciences of interpretation exemplified by geology.

Health benefits of geologic materials and geologic processes

Science.gov (United States)

Finkelman, R.B.

2006-01-01

The reemerging field of Medical Geology is concerned with the impacts of geologic materials and geologic processes on animal and human health. Most medical geology research has been focused on health problems caused by excess or deficiency of trace elements, exposure to ambient dust, and on other geologically related health problems or health problems for which geoscience tools, techniques, or databases could be applied. Little, if any, attention has been focused on the beneficial health effects of rocks, minerals, and geologic processes. These beneficial effects may have been recognized as long as two million years ago and include emotional, mental, and physical health benefits. Some of the earliest known medicines were derived from rocks and minerals. For thousands of years various clays have been used as an antidote for poisons. "Terra sigillata," still in use today, may have been the first patented medicine. Many trace elements, rocks, and minerals are used today in a wide variety of pharmaceuticals and health care products. There is also a segment of society that believes in the curative and preventative properties of crystals (talismans and amulets). Metals and trace elements are being used in some of today's most sophisticated medical applications. Other recent examples of beneficial effects of geologic materials and processes include epidemiological studies in Japan that have identified a wide range of health problems (such as muscle and joint pain, hemorrhoids, burns, gout, etc.) that may be treated by one or more of nine chemically distinct types of hot springs, and a study in China indicating that residential coal combustion may be mobilizing sufficient iodine to prevent iodine deficiency disease. ?? 2006 MDPI. All rights reserved.

Key scientific challenges in geological disposal of high level radioactive waste

International Nuclear Information System (INIS)

Wang Ju

2007-01-01

The geological disposal of high radioactive waste is a challenging task facing the scientific and technical world. This paper introduces the latest progress of high level radioactive disposal programs in the latest progress of high level radioactive disposal programs in the world, and discusses the following key scientific challenges: (1) precise prediction of the evolution of a repository site; (2) characteristics of deep geological environment; (3) behaviour of deep rock mass, groundwater and engineering material under coupled con-ditions (intermediate to high temperature, geostress, hydraulic, chemical, biological and radiation process, etc); (4) geo-chemical behaviour of transuranic radionuclides with low concentration and its migration with groundwater; and (5) safety assessment of disposal system. Several large-scale research projects and several hot topics related with high-level waste disposal are also introduced. (authors)

Applications of Micro-Fourier Transform Infrared Spectroscopy (FTIR) in the Geological Sciences—A Review

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Chen, Yanyan; Zou, Caineng; Mastalerz, Maria; Hu, Suyun; Gasaway, Carley; Tao, Xiaowan

2015-01-01

Fourier transform infrared spectroscopy (FTIR) can provide crucial information on the molecular structure of organic and inorganic components and has been used extensively for chemical characterization of geological samples in the past few decades. In this paper, recent applications of FTIR in the geological sciences are reviewed. Particularly, its use in the characterization of geochemistry and thermal maturation of organic matter in coal and shale is addressed. These investigations demonstrate that the employment of high-resolution micro-FTIR imaging enables visualization and mapping of the distributions of organic matter and minerals on a micrometer scale in geological samples, and promotes an advanced understanding of heterogeneity of organic rich coal and shale. Additionally, micro-FTIR is particularly suitable for in situ, non-destructive characterization of minute microfossils, small fluid and melt inclusions within crystals, and volatiles in glasses and minerals. This technique can also assist in the chemotaxonomic classification of macrofossils such as plant fossils. These features, barely accessible with other analytical techniques, may provide fundamental information on paleoclimate, depositional environment, and the evolution of geological (e.g., volcanic and magmatic) systems. PMID:26694380

Geologic drivers of late ordovician faunal change in laurentia: investigating links between tectonics, speciation, and biotic invasions.

Directory of Open Access Journals (Sweden)

David F Wright

Full Text Available Geologic process, including tectonics and global climate change, profoundly impact the evolution of life because they have the propensity to facilitate episodes of biogeographic differentiation and influence patterns of speciation. We investigate causal links between a dramatic faunal turnover and two dominant geologic processes operating within Laurentia during the Late Ordovician: the Taconian Orogeny and GICE related global cooling. We utilize a novel approach for elucidating the relationship between biotic and geologic changes using a time-stratigraphic, species-level evolutionary framework for articulated brachiopods from North America. Phylogenetic biogeographic analyses indicate a fundamental shift in speciation mode-from a vicariance to dispersal dominated macroevolutionary regime-across the boundary between the Sandbian to Katian Stages. This boundary also corresponds to the onset of renewed intensification of tectonic activity and mountain building, the development of an upwelling zone that introduced cool, nutrient-rich waters into the epieric seas of eastern Laurentia, and the GICE isotopic excursion. The synchronicity of these dramatic geologic, oceanographic, and macroevolutionary changes supports the influence of geologic events on biological evolution. Together, the renewed tectonic activity and oceanographic changes facilitated fundamental changes in habitat structure in eastern North America that reduced opportunities for isolation and vicariance. They also facilitated regional biotic dispersal of taxa that led to the subsequent establishment of extrabasinal (=invasive species and may have led to a suppression of speciation within Laurentian faunas. Phylogenetic biogeographic analysis further indicates that the Richmondian Invasion was a multidirectional regional invasion event that involved taxa immigrating into the Cincinnati region from basins located near the continental margins and within the continental interior.

Hydro-Geological Hazard Temporal Evolution during the last seven decades in the Solofrana River Basin—Southern Italy

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Longobardi, Antonia; Diodato, Nazzareno; Mobilia, Mirka

2017-04-01

Extremes precipitation events are frequently associated to natural disasters falling within the broad spectrum of multiple damaging hydrological events (MDHEs), defined as the simultaneously triggering of different types of phenomena, such as landslides and floods. The power of the rainfall (duration, magnitude, intensity), named storm erosivity, is an important environmental indicator of multiple damaging hydrological phenomena. At the global scale, research interest is actually devoted to the investigation of non-stationary features of extreme events, and consequently of MDHEs, which appear to be increasing in frequency and severity. The Mediterranean basin appears among the most vulnerable regions with an expected increase in occurring damages of about 100% by the end of the century. A high concentration of high magnitude and short duration rainfall events are, in fact, responsible for the largest rainfall erosivity and erosivity density values within Europe. The aim of the reported work is to investigate the relationship between the temporal evolution of severe geomorphological events and combined precipitation indices as a tool to improve understanding the hydro-geological hazard at the catchment scale. The case study is the Solofrana river basin, Southern Italy, which has been seriously and consistently in time affected by natural disasters. Data for about 45 MDH events, spanning on a decadal scale 1951-2014, have been collected and analyzed for this purpose. A preliminary monthly scale analysis of event occurrences highlights a pronounced seasonal characterization of the phenomenon, as about 60% of the total number of reported events take place during the period from September to November. Following, a statistical analysis clearly indicates a significant increase in the frequency of occurrences of MDHEs during the last decades. Such an increase appears to be related to non-stationary features of an average catchment scale rainfall-runoff erosivity index

Introduction to the special issue on the Phanerozoic geology of Egypt in honor of Professor Mohamed El-Bahay Issawi

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Abdeen, M. M.; Tewksbury, B.; Abdelsalam, M. G.; Tarabees, E.

2017-12-01

This issue is dedicated to Professor Mohamed El-Bahay Issawi in recognition of his monumental contributions to an understanding of the Phanerozoic evolution of the northern part of Africa. During his long and productive career in the Egyptian Geological Survey and Mining Authority (EGSMA), he was committed to deciphering the geological history and resources of the Phanerozoic of Egypt. Professor Issawi is widely recognized for his influential stratigraphic-tectonic models that were an inspiration for generations of Egyptian geoscientists from the 1960s onward. His models and expertise helped to attract international interest and involvement in fundamental programs of research on the Phanerozoic geology of Egypt and specifically on geoarchaeology.

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)

Polycyclic evolution of the Quadrilatero Ferrifero: an analysis based on the actual knowledge of the U-Pb geochronology and Sm-Nd isotopic geochemistry

International Nuclear Information System (INIS)

Carneiro, Mauricio Antonio; Noce, Carlos Mauricio; Teixeira, Wilson

1995-01-01

The tectonic evolution of the Quadrilatero Ferrifero region, based on geochronological U-Pb, Pb-Pb, Sm-Nd, Rb-Sr e K-Ar data, is characterized by several processes of crustal growth, which began in Middle Archean. The Lower Archean geological evolution of the Quadrilatero Ferrifero was finished by the Rio de Velhas tectono-thermal event around 2,78 Ga. After this, during the proterozoic era, three tectono-sedimentary cycles took place on this Lower Archean crustal fragment, whose products are represented by the meta sedimentary sequences of the Minas Supergroup, Itacolomi Group and Espinhaco Supergroup. The Transamazonico Event (ca. 2,0 Ga) ended the geological evolution of Minas Supergroup, but its geological records did not have the same size imprints throughout region. Many places, such as the Bonfim Metamorphic Complex, were not affected by this tectonic event. Later tectonic event. Later tectonic events (e.g. Brasiliano) had even more discrete geological occurred during the Proterozoic era, when many sedimentary basins developed (e.g. Espinhaco and Sao Francisco basins). (author)

Geology and religion - historical perspective and current problems

Science.gov (United States)

Kölbl-Ebert, Martina

2010-05-01

Today, when referring to the relationship between geology and religion, people usually at once think of Christian (and other) fundamentalists and their chronic palaeontological illiteracy leading to Creationism, to Intelligent Design, and a distrust of science in general among them most prominently geology, palaeontology and evolutionary biology. Thus the relationship of geology and religion is usually considered to be under strain. In former times things used to be quite different, and for most of human history the observation of geological phenomena and the acquisition of geological expertise was intimately connected with religious ideas. The Judeo-Christian sense of a finite Earth history prepared the ground for accepting the Earth's different strata as testimony to the development of our globe through time. It was this religious, theological framework, from which the early geology started to evolve. However, with increasing observations there was a growing mismatch between what was expected according to ancient, scriptural authorities and the actual data. The release of geology from religious connotations or associations was a development closely connected with the Enlightenment, when geology and religion started to drift apart not with a violent rupture but in a subtle and sometimes circuitous manner. However, outside the group of people with geological expertise, not all was smooth and peaceful, and some conservative clergymen as well as laypersons were rather shocked by the new ideas that came with geology: the immensity of the timescale, a dynamic Earth, not just a ruin shaped by the Deluge, and a dynamic biology too with the Darwinian theory of evolution, which was founded in part on palaeontological evidence and the assumption of a long geological time scale. Nevertheless and interestingly the Creationism we face today is a rather recent phenomenon influenced by a number of motives, most of them philosophical and theological in nature. And so, the current

The intercrater plains of Mercury and the Moon: Their nature, origin and role in terrestrial planet evolution. Geologic map analyses: Correlation of geologic and cratering histories. Ph.D. Thesis

Science.gov (United States)

Leake, M. A.

1982-01-01

Geologic map analyses are expanded, beginning with a discussion of particular regions which may illustrate volcanic and ballistic plains emplacement on Mercury. Major attention is focused on the surface history of Mercury through discussion of the areal distribution of plains and craters and the paleogeologic maps of the first quadrant. A summary of the lunar intercrater plains formation similarly interrelates the information from the Moon's geologic and cratering histories.

Post-Viking view of Martian geologic evolution

International Nuclear Information System (INIS)

Arvidson, R.E.; Goettel, K.A.; Hohenberg, C.M.

1980-01-01

The mean density, 3.393 g/cm 3 , and the estimated moment of inertia factor constrain the density distribution within Mars but do not define it uniquely. For plausible core density, core radii can range from approx. 1350 to approx. 2200 km, with the core constituting from approx. 13 to approx. 35% of the planet's mass. Possible extremes for the zero-pressure density of the Martian mantle could be as high as 3.6 g/cm 3 or as low as 3.3 g/cm 3 . The Martian mantle is probably denser than the terrestrial mantle. The dominant Martian lavas are probably mafic or ultramafic. Martian surface materials probably consist of variable proportions of mafic igneous minerals and weathering products, the latter primarily oxides and carbonates. A major geologic dichotomy exists between the complex northern plains and the ancient southern cratered terrain. The Tharsis plateau, which dominates the low-degree harmonics of the gravity field, appears to be only partially compensated; Olympus Mons appears to be completely uncompensated. Substantial stresses must be supported, either statically by a thick, rigid lithosphere, or dynamically. Mean crustal thicknesses from 23 to 40 km have been obtained from modeling of Bouguer gravity data. Lithospheric thicknesses from 25 to 50 km under volcanoes in the Tharsis and Elysium provinces to >150 km under olympus Mons have been obtained from consideration of the effects of mass loading by volcanic constructs. Many of the compressional and extensional features on Mars have orientations consistent with formation by fracturing in response to loading by the Tharsis plateau. The deficiency of small craters within cratered terrain is attributed to obliteration by volcanism. The maximum resurfacing rate due to volcanism occurred between 1.0 and 1.5 b.y. ago if a constant cratering flux is assumed and between 3.5 and 4.0 b.y. ago if the lunar cratering flux (scaled to Mars) is assumed

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.

The U.S. Geological Survey Geologic Collections Management System (GCMS)—A master catalog and collections management plan for U.S. Geological Survey geologic samples and sample collections

Science.gov (United States)

,

2015-01-01

The U.S. Geological Survey (USGS) is widely recognized in the earth science community as possessing extensive collections of earth materials collected by research personnel over the course of its history. In 2006, a Geologic Collections Inventory was conducted within the USGS Geology Discipline to determine the extent and nature of its sample collections, and in 2008, a working group was convened by the USGS National Geologic and Geophysical Data Preservation Program to examine ways in which these collections could be coordinated, cataloged, and made available to researchers both inside and outside the USGS. The charge to this working group was to evaluate the proposition of creating a Geologic Collections Management System (GCMS), a centralized database that would (1) identify all existing USGS geologic collections, regardless of size, (2) create a virtual link among the collections, and (3) provide a way for scientists and other researchers to obtain access to the samples and data in which they are interested. Additionally, the group was instructed to develop criteria for evaluating current collections and to establish an operating plan and set of standard practices for handling, identifying, and managing future sample collections. Policies and procedures promoted by the GCMS would be based on extant best practices established by the National Science Foundation and the Smithsonian Institution. The resulting report—USGS Circular 1410, “The U.S. Geological Survey Geologic Collections Management System (GCMS): A Master Catalog and Collections Management Plan for U.S. Geological Survey Geologic Samples and Sample Collections”—has been developed for sample repositories to be a guide to establishing common practices in the collection, retention, and disposal of geologic research materials throughout the USGS.

Geologic evolution of the Lost City Hydrothermal Field

Science.gov (United States)

Denny, Alden R.; Kelley, Deborah S.; Früh-Green, Gretchen L.

2016-02-01

The Lost City Hydrothermal Field (LCHF) is a novel serpentinite-hosted vent field located on the Atlantis Massif southern wall. Results of 2 m resolution bathymetry, side scan, and video and still imagery, integrated with direct submersible observations provide the first high-resolution geologic map of the LCHF. These data form the foundation for an evolutionary model for the vent system over the past >120,000 years. The field is located on a down-dropped bench 70 m below the summit of the massif. The bench is capped by breccia and pelagic carbonate deposits underlain by variably deformed and altered serpentinite and gabbroic rocks. Hydrothermal activity is focused at the 60 m tall, 100 m across, massive carbonate edifice "Poseidon," which is venting 91°C fluid. Hydrothermal activity declines south and west of the Poseidon complex and dies off completely at distances greater than 200 m. East of Poseidon, the most recent stage of hydrothermal flow is characterized by egress of diffuse fluids from narrow fissures within a low-angle, anastomosing mylonite zone. South of the area of current hydrothermal activity, there is evidence of two discrete previously unrecognized relict fields. Active venting sites defined by carbonate-filled fissures that cut the carbonate cap rock at the summit of the massif mark the present-day northernmost extent of venting. These spatial relationships reflect multiple stages of field development, the northward migration of venting over time, and the likely development of a nascent field at the massif summit.

Fire feedbacks over geological time and the evolution of atmospheric oxygen concentration

Science.gov (United States)

Mills, B.; Belcher, C.; Lenton, T. M.

2017-12-01

During the 4.5 billion year history of the Earth, the concentration of oxygen in the atmosphere has risen from trace levels to today's 21%. Yet over the last 400 million years, O2 concentration appears to have remained within a relatively narrow range (around 15% - 30%), despite dramatic changes in the nature of global biogeochemical cycling. This stability has been crucial for continued animal evolution, and is thought to have arisen through feedbacks between oxygen, wildfire and plant productivity: the strong oxygen- dependence of fire initiation and spread means that global photosynthetic primary productivity is suppressed when oxygen levels are high, and enhanced when levels are low. We present biogeochemical modelling of the long term carbon and oxygen cycles, which aims to capture the operation of the wildfire feedback alongside other key processes. We find that wildfire can effectively stabilize long term oxygen concentrations, but that the nature of this feedback has changed as plant evolution has provided different fuels. Specifically, the evolution of early angiosperms during the Cretaceous period provided new understory fuels that more easily facilitated crown and canopy fires. Adding these dynamics to our model produces a more stable system over long timescales, and the model predicts that oxygen concentration has declined towards the present day - a prediction that is supported by other independent estimates.

Applications of geological labs on chip for CO_2 storage issues

International Nuclear Information System (INIS)

Morais, Sandy

2016-01-01

CO_2 geological storage in deep saline aquifers represents a mediation solution for reducing the anthropogenic CO_2 emissions. Consequently, this kind of storage requires adequate scientific knowledge to evaluate injection scenarios, estimate reservoir capacity and assess leakage risks. In this context, we have developed and used high pressure/high temperature micro-fluidic tools to investigate the different mechanisms associated with CO_2 geological storage in deep saline aquifers. The silicon-Pyrex 2D porous networks (Geological Labs On Chips) can replicate the reservoir p,T conditions (25 ≤ T ≤ 50 C, 50 ≤ p ≤ 10 MPa), geological and topological properties. This thesis manuscript first highlights the strategies developed during this work to fabricate the GLoCs and to access to global characteristics of our porous media such as porosity and permeability, which are later compared to numerical modelling results. The carbon dioxide detection in GLoCs mimicking p,T conditions of geological reservoirs by using the direct integration of optical fiber for IR spectroscopy is presented. I then detail the strategies for following the dissolution of carbonates in GLoCs with X-rays laminography experiments.Then, the manuscript focuses on the use of GLoCs to investigate each CO_2 trapping mechanism at the pore scale. The direct optical visualization and image processing allow us to follow the evolution of the injected CO_2/aqueous phase within the reservoir, including displacement mechanisms and pore saturation levels. Eventually, I present the ongoing works such as experiments with reactive brines and hydrates formations in porous media [fr

Correspondence of Mesozoic Eustatic Sea-Level Change with Palaeoclimate Proxies: Evidence for Glacio-Eustasy?

Science.gov (United States)

Simmons, M.; Davies, A.; Gréselle, B.

2011-12-01

Large-scale changes in stratigraphic architecture and facies that are brought about by changes in relative sea-level have been the focus of much academic and industry study over the last few decades. The authors, plus numerous colleagues, have studied over 11,000 stratigraphic sections worldwide. By applying biostratigraphic and chemostratigraphic calibration in suitable locations from this dataset it is possible to demonstrate over 250 synchronous global sequence stratigraphic events in the Phanerozoic including over 100 in the Mesozoic. This then raises the question - what causes globally synchronous eustatic sea-level change? To answer this question requires an understanding of both the pace and amplitude of the observed eustatic sea-level change. In successions where duration can be deduced from orbital forcing cycles, our observed sea-level changes appear to be relatively rapid - less than 500,000 years, for example, for sea-level rises in the Late Jurassic. The amplitude of such rises is in the order of tens of metres. Such rates and amplitudes as inferred from our global model preclude tectonism as a primary driver and implicate glacio-eustacy as a key driving mechanism, even in supposed "greenhouse times". Given the clear economic importance of understanding the underlying mechanisms driving this eustatic change we have compiled records of key isotopic proxies through the entire Mesozoic in an effort to explore the relationship between global sea-level and palaeoclimate. Our research reveals a clear link between many large-scale maximum flooding events with known episodes of palaeoclimatic warming and between climatic cooling events and lowstand intervals, further implicating glacio-eustacy. In addition to the isotopic proxy evidence we have also compiled direct indicators for the occurrence of cold polar conditions, including the presence of ice sheets, in the Mesozoic (e.g. tillites, glendonites). This has been incorporated into plate tectonic

Study on geology and geological structure based on literature studies

International Nuclear Information System (INIS)

Funaki, Hironori; Ishii, Eiichi; Yasue, Ken-ichi; Takahashi, Kazuharu

2005-03-01

Japan Nuclear Cycle Development Institute (JNC) is proceeding with underground research laboratory (URL) project for the sedimentary rock in Horonobe, Hokkaido. This project is an investigation project which is planned over 20 years. Surface-based investigations (Phase 1) have been conducted for the present. The purposes of the Phase 1 are to construct the geological environment model (geological-structural, hydrogeological, and hydrochemical models) and to confirm the applicability of investigation technologies for the geological environment. The geological-structural model comprises the base for the hydrogeological and hydrochemical models. We constructed the geological-structural model by mainly using data obtained from literature studies. Particulars regarding which data the model is based on and who has performed the interpretation are also saved for traceability. As a result, we explain the understanding of degree and the need of information on stratigraphy and discontinuous structure. (author)

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.

Biogeographical patterns of Myrcia s.l. (Myrtaceae) and their correlation with geological and climatic history in the Neotropics.

Science.gov (United States)

Santos, Matheus Fortes; Lucas, Eve; Sano, Paulo Takeo; Buerki, Sven; Staggemeier, Vanessa Graziele; Forest, Félix

2017-03-01

Many recent studies discuss the influence of climatic and geological events in the evolution of Neotropical biota by correlating these events with dated phylogenetic hypotheses. Myrtaceae is one of the most diverse Neotropical groups and it therefore a good proxy of plant diversity in the region. However, biogeographic studies on Neotropical Myrtaceae are still very limited. Myrcia s.l. is an informal group comprising three accepted genera (Calyptranthes, Marlierea and Myrcia) making up the second largest Neotropical group of Myrtaceae, totalling about 700 species distributed in nine subgroups. Exclusively Neotropical, the group occurs along the whole of the Neotropics with diversity centres in the Caribbean, the Guiana Highlands and the central-eastern Brazil. This study aims to identify the time and place of divergence of Myrcia s.l. lineages, to examine the correlation in light of geological and climatic events in the Neotropics, and to explore relationships among Neotropical biogeographic areas. A dated phylogenetic hypothesis was produced using BEAST and calibrated by placing Paleomyrtinaea princetonensis (56Ma) at the root of the tree; biogeographic analysis used the DEC model with dispersal probabilities between areas based on distance and floristic affinities. Myrcia s.l. originated in the Montane Atlantic Forest between the end of Eocene and early Miocene and this region acted as a secondary cradle for several lineages during the evolution of this group. The Caribbean region was important in the diversification of the Calyptranthes clade while the Guayana shield appears as ancestral area for an older subgroup of Myrcia s.l. The Amazon Forest has relatively low diversity of Myrcia s.l. species but appears to have been important in the initial biogeographic history of old lineages. Lowland Atlantic Forest has high species diversity but species rich lineages did not originate in the area. Diversification of most subgroups of Myrcia s.l. occurred throughout

Dating Saharan dust deposits on Lanzarote (Canary Islands) by luminescence dating techniques and their implication for palaeoclimate reconstruction of NW Africa

Science.gov (United States)

von Suchodoletz, H.; Fuchs, M.; ZöLler, L.

2008-02-01

Lava flow dammed valleys (Vegas) on Lanzarote (Canary Islands) represent unique sediment traps, filled with autochthonous volcanic material and allochthonous Saharan dust. These sediments and the intercalated palaeosoil sediments document past environmental change of the last glacial-interglacial cycles, both on Lanzarote and in NW Africa. A reliable chronology must be established to use these sediment archives for palaeoclimate reconstructions. Owing to the lack of organic material and the limiting time range of the 14C-dating method, luminescence dating is the most promising method for these sediments. However, the fluvio-eolian character of these sediments is a major problem for luminescence dating, because these sediments are prone to insufficient resetting of the parent luminescence signal (bleaching) prior to sedimentation. To check for the best age estimates, we compare the bleaching behavior of (1) different grain sizes (coarse- versus fine-grain quartz OSL) and (2) different minerals (fine-grain feldspar IRSL versus fine-grain quartz OSL). The results show that owing to its bleaching characteristics, quartz is the preferable mineral for luminescence dating. On the basis of the fine- and coarse-grain quartz OSL age estimates, a chronostratigraphy up to 100 ka could be established. Beyond this age limit for OSL quartz, the chronostratigraphy could be extended up to 180 ka by correlating the vega sediments with dated marine sediment archives.

Destination: Geology?

Science.gov (United States)

Price, Louise

2016-04-01

"While we teach, we learn" (Roman philosopher Seneca) One of the most beneficial ways to remember a theory or concept is to explain it to someone else. The offer of fieldwork and visits to exciting destinations is arguably the easiest way to spark a students' interest in any subject. Geology at A-Level (age 16-18) in the United Kingdom incorporates significant elements of field studies into the curriculum with many students choosing the subject on this basis and it being a key factor in consolidating student knowledge and understanding. Geology maintains a healthy annual enrollment with interest in the subject increasing in recent years. However, it is important for educators not to loose sight of the importance of recruitment and retention of students. Recent flexibility in the subject content of the UK curriculum in secondary schools has provided an opportunity to teach the basic principles of the subject to our younger students and fieldwork provides a valuable opportunity to engage with these students in the promotion of the subject. Promotion of the subject is typically devolved to senior students at Hessle High School and Sixth Form College, drawing on their personal experiences to engage younger students. Prospective students are excited to learn from a guest speaker, so why not use our most senior students to engage and promote the subject rather than their normal subject teacher? A-Level geology students embarking on fieldwork abroad, understand their additional responsibility to promote the subject and share their understanding of the field visit. They will typically produce a series of lessons and activities for younger students using their newly acquired knowledge. Senior students also present to whole year groups in seminars, sharing knowledge of the location's geology and raising awareness of the exciting destinations offered by geology. Geology fieldwork is always planned, organised and led by the member of staff to keep costs low, with recent visits

Investigating extreme flood response to Holocene palaeoclimate in the Chinese monsoonal zone: A palaeoflood case study from the Hanjiang River

Science.gov (United States)

Guo, Yongqiang; Huang, Chun Chang; Pang, Jiangli; Zha, Xiaochun; Zhou, Yali; Wang, Longsheng; Zhang, Yuzhu; Hu, Guiming

2015-06-01

Palaeoflood events recorded by slackwater deposits (SWDs) were investigated extensively by sedimentological criteria of palaeohydrology along the upper Hanjiang River valley. Modern flood SWDs were collected for comparison with palaeoflood SWD in the same reaches. Three typical palaeoflood SWDs were observed within Holocene loess-soil blanket on the first river terrace land. The grain size distributions of palaeoflood SWDs are similar to modern flood SWDs, whereas they are different from eolian loess and soil. Palaeoflood SWD lies in three major pedo-stratigraphic boundaries (TS/L0, L0/S0, and S0/Lt) in the Holocene loess-soil profiles. The chronology of three palaeoflood episodes was established by OSL dating and pedo-stratigraphic correlation with the well-dated Holocene loess-soil profiles in the upper Hanjiang River basin. Holocene palaeoflood events were dated to 9500-8500, 3200-2800, and 1800-1700 a B.P., respectively. Palaeoflood discharges were estimated by the palaeoflood model (i.e., slope-area method and step-backwater method). The highest discharges are 51,680-53,950 m3 s- 1 at the 11,500-time scale in the Xunyang reach of the upper Hanjiang River valley. Holocene extraordinary hydroclimatic events in the Hanjiang River often result from abnormal atmospheric circulations from Southwest monsoons in the Chinese monsoonal zone. These results provide a regional expression of extreme flood response to Holocene palaeoclimate to understand the effects of global climatic variations on the river system dynamics.

Site descriptive modelling during characterization for a geological repository for nuclear waste in Sweden

International Nuclear Information System (INIS)

Stroem, A.; Andersson, J.; Skagius, K.; Winberg, A.

2008-01-01

The Swedish programme for geological disposal of spent nuclear fuel is approaching major milestones in the form of permit applications for an encapsulation plant and a deep geologic repository. This paper presents an overview of the bedrock and surface modelling work that comprises a major part of the on-going site characterization in Sweden and that results in syntheses of the sites, called site descriptions. The site description incorporates descriptive models of the site and its regional setting, including the current state of the geosphere and the biosphere as well as natural processes affecting long-term evolution. The site description is intended to serve the needs of both repository engineering with respect to layout and construction, and safety assessment, with respect to long-term performance. The development of site-descriptive models involves a multi-disciplinary interpretation of geology, rock mechanics, thermal properties, hydrogeology, hydrogeochemistry, transport properties and ecosystems using input in the form of available data for the surface and from deep boreholes

Field Geology/Processes

Science.gov (United States)

Allen, Carlton; Jakes, Petr; Jaumann, Ralf; Marshall, John; Moses, Stewart; Ryder, Graham; Saunders, Stephen; Singer, Robert

1996-01-01

The field geology/process group examined the basic operations of a terrestrial field geologist and the manner in which these operations could be transferred to a planetary lander. Four basic requirements for robotic field geology were determined: geologic content; surface vision; mobility; and manipulation. Geologic content requires a combination of orbital and descent imaging. Surface vision requirements include range, resolution, stereo, and multispectral imaging. The minimum mobility for useful field geology depends on the scale of orbital imagery. Manipulation requirements include exposing unweathered surfaces, screening samples, and bringing samples in contact with analytical instruments. To support these requirements, several advanced capabilities for future development are recommended. Capabilities include near-infrared reflectance spectroscopy, hyper-spectral imaging, multispectral microscopy, artificial intelligence in support of imaging, x ray diffraction, x ray fluorescence, and rock chipping.

Safety case development in the Japanese programme for geological disposal of HLW: Evolution in the generic stage

International Nuclear Information System (INIS)

Ueda, Hiroyoshi; Ishiguro, Katsuhiko; Takeuchi, Mitsuo; Fujihara, Hiroshi; Takeda, Seietsu

2014-01-01

In the Japanese programme for nuclear power generation, the safe management of the resulting radioactive waste, particularly vitrified high-level waste (HLW) from fuel reprocessing, has been a major concern and a focus of R and D since the late 70's. According to the specifications in a report issued by an advisory committee of the Japan Atomic Energy Commission (JAEC, 1997), the Second Progress Report on R and D for the Geological Disposal of HLW (H12 report) (JNC, 2000) was published after two decades of R and D activities and showed that disposal of HLW in Japan is feasible and can be practically implemented at sites which meet certain geological stability requirements. The H12 report supported government decisions that formed the basis of the 'Act on Final Disposal of Specified Radioactive Waste' (Final Disposal Act), which came into force in 2000. The Act specifies deep geological disposal of HLW at depths greater than 300 metres, together with a stepwise site selection process in three stages. Following the Final Disposal Act, the supporting 'Basic Policy for Final Disposal' and the 'Final Disposal Plan' were authorised in the same year. (authors)

Applications of Micro-Fourier Transform Infrared Spectroscopy (FTIR in the Geological Sciences—A Review

Directory of Open Access Journals (Sweden)

Yanyan Chen

2015-12-01

Full Text Available Fourier transform infrared spectroscopy (FTIR can provide crucial information on the molecular structure of organic and inorganic components and has been used extensively for chemical characterization of geological samples in the past few decades. In this paper, recent applications of FTIR in the geological sciences are reviewed. Particularly, its use in the characterization of geochemistry and thermal maturation of organic matter in coal and shale is addressed. These investigations demonstrate that the employment of high-resolution micro-FTIR imaging enables visualization and mapping of the distributions of organic matter and minerals on a micrometer scale in geological samples, and promotes an advanced understanding of heterogeneity of organic rich coal and shale. Additionally, micro-FTIR is particularly suitable for in situ, non-destructive characterization of minute microfossils, small fluid and melt inclusions within crystals, and volatiles in glasses and minerals. This technique can also assist in the chemotaxonomic classification of macrofossils such as plant fossils. These features, barely accessible with other analytical techniques, may provide fundamental information on paleoclimate, depositional environment, and the evolution of geological (e.g., volcanic and magmatic systems.

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

Brazil Geologic Basic Survey Program - Barbacena - Sheet SF.23-X-C-III -Minas Gerais State

International Nuclear Information System (INIS)

Brandalise, L.A.

1991-01-01

The present report refers to the Barbacena sheet (SF.23-X-C-III) systematic geological mapping, on the 1:10,000 scale, related to the Levantamentos Geologicos Basicos do Brasil Program - PLGB, carried out by CPRM for the DNPM. Integrated to geochemical and geophysical surveys, the geological mapping not only yielded geophysical and geochemical maps but a consistent to the 1:100.000 scale Metallogenetic/Provisional one as well. The geological mapping carried out during the Project has really evidenced that samples of distinct stratigraphic units had been employed to define the one and only isochrone. However geochronologic Rb/Sr dating performed during the geological mapping phase evidenced Archean ages for rocks of the Sao Bento dos Torres Metamorphic Suite (2684 ± 110 m.y.) and ages of about 2000 m.y. for the Ressaquinha Complex rocks. An analysis of crustal evolution patterns based on geological mapping, gravimetric survey data, aeromagnetometry and available geochronologic data is given in the Chapter 6, Part II, in the test. Major element oxides, trace-elements and rare-earths elements were analysed to establish parameters for the rocks environment elucidation. Geochemical survey was carried out with base on pan concentrated and stream sediments distributed throughout the sheet. (author)

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 ...

Geological boundary conditions for a safety demonstration and verification concept for a HLW repository in claystone in Germany. AnSichT

Energy Technology Data Exchange (ETDEWEB)

Stark, Lena; Bebiolka, Anke; Gerardi, Johannes [Federal Institute for Geosciences and Natural Resources (BGR), Hannover (Germany). Dept. of Underground Space for Storage and Economic Use; and others

2015-07-01

Within the framework of the R and D project ''AnSichT'', DBE TECHNOLOGY, BGR and GRS are developing a method to demonstrate the safety of a HLW repository in claystone in Germany. The methodological approach basing on a holistic concept, links the legal and geologic boundary conditions, the disposal and closure concept, the demonstration of barrier integrity, and the long-term analysis of the repository evolution as well. The geologic boundary conditions are specified by the description of the geological situation and generic models, the selection of representative parameters and geoscientific long-term predictions. They form a fundament for the system analysis.

Research on geological disposal: R and D concept on geological disposal

International Nuclear Information System (INIS)

1993-01-01

The objective on geological disposal of high-level radioactive wastes are to ensure the long term radiological protection of the human and his environment in accordance with current internationally agreed radiation protection principles. The principle of geological disposal is to settle the high-level wastes in deep underground so as to isolate them from the human and his environment considering the existence of groundwater. Japan is currently in the stage of assessing technical feasibility of geological disposal to the extent practicable. In accordance with the AEC (Atomic Energy Commission) policy in 1989, PNC (Power Reactor and Nuclear Fuel Development Corporation) has conducted the research and development on geological disposal in three areas: 1) studies of geological environment, 2) research and development of disposal technology, and 3) performance assessment study. (author)

Research on the evolution model and deformation mechanisms of Baishuihe landslide based on analyzing geologic process of slope

Science.gov (United States)

Zhang, S.; Tang, H.; Cai, Y.; Tan, Q.

2016-12-01

The landslide is a result of both inner and exterior geologic agents, and inner ones always have significant influences on the susceptibility of geologic bodies to the exterior ones. However, current researches focus more on impacts of exterior factors, such as precipitation and reservoir water, than that of geologic process. Baishuihe landslide, located on the south bank of Yangtze River and 56km upstream from the Three Gorges Project, was taken as the study subject with the in-situ investigation and exploration carried out for the first step. After the spatial analysis using the 3D model of topography built by ArcGIS (Fig.1), geologic characteristics of the slope that lies in a certain range near the Baishuihe landslide on the same bank were investigated for further insights into geologic process of the slope, with help of the geological map and structure outline map. Baishuihe landslide developed on the north limb of Baifuping anticline, a dip slope on the southwest margin of Zigui basin. The eastern and western boundaries are both ridges and in the middle a distinct slide depression is in process of deforming. Evolutionary process of Baishuihe landslide includes three steps below. 1) Emergence of Baifuping anticline leaded to interbedded dislocation, tension cracks and joint fractures in bedrocks. 2) Weathering continuously weakened strength of soft interlayers in the Shazhenxi Formation (T3s). 3) Rock slide caused by neotectonics happened on a large scale along the weak layers and joint planes, forming initial Baishuihe landslide. Although the landslide has undergone reconstruction for a long time, it could still be divided clearly into two parts, namely a) the rock landslide at the back half (south) and b) the debris landslide at the front half (north). a) The deformation mechanism for the rock landslide is believed to be deterioration in strength of weak bedding planes due to precipitation and free face caused by human activities or river incision. b

Introductory Geology From the Liberal Arts Approach: A Geology-Sociology Linked Course

Science.gov (United States)

Walsh, E. O.; Davis, E.

2008-12-01

Geology can be a hard sell to college students, especially to college students attending small, liberal arts institutions in localities that lack exaggerated topography. At these schools, Geology departments that wish to grow must work diligently to attract students to the major; professors must be able to convince a wider audience of students that geology is relevant to their everyday lives. Toward this end, a Physical Geology course was linked with an introductory Sociology course through the common theme of Consumption. The same students took the two courses in sequence, beginning with the Sociology course and ending with Physical Geology; thus, students began by discussing the role of consumption in society and ended by learning about the geological processes and implications of consumption. Students were able to ascertain the importance of geology in their daily lives by connecting Earth processes to specific products they consume, such as cell phones and bottled water. Students were also able to see the connection between seemingly disparate fields of study, which is a major goal of the liberal arts. As a theme, Consumption worked well to grab the attention of students interested in diverse issues, such as environmental science or social justice. A one-hour lecture illustrating the link between sociology and geology was developed for presentation to incoming freshmen and their parents to advertise the course. Initial response has been positive, showing an increase in awareness of geological processes among students with a wide range of interests.

Geology of the Southern Utopia Planitia Highland-Lowland Boundary Plain: First Year Results and Second Year Plan

Science.gov (United States)

Skinner, J. A., Jr.; Tanaka, K. L.; Hare, T. M.

2008-01-01

The southern Utopia highland-lowland boundary (HLB) extends >1500 km westward from northern Nepenthes Mensae to the topographic saddle that separates Isidis and Utopia Planitiae. It contains bench-like platforms that contain depressions, pitted cones (some organized into arcuate chains and thumbprint terrain), isolated domes, lineated depressions, buried circular depressions, ring fractures, polygonal fractures, and other locally- to regionally-dispersed landforms [1]. The objective of our mapping project is to clarify the geologic evolution of the southern Utopia Planitia HLB by identifying the geologic, structural, and stratigraphic relationships of surface materials in MTMs 10237, 15237, 20237, 10242, 15242, 20242, 10247, 15247, and 20247.

Goethe's Italian Journey and the geological landscape

Science.gov (United States)

Coratza, Paola; Panizza, Mario

2015-04-01

"integrated", meaning integration between natural components, including geological, biological and anthropogenic elements, climate, history, architecture, literature etc. Secondly, Goethe's scientific intuitions (in this case the geological ones) were compared with the evolution of scientific knowledge up to most recent times, which at times confirm what Goethe had already realised. This project is based on the description of the stages of his journey, in the light of modern results of investigations carried out in geology, geomorphology, mineralogy etc. This research is grateful for the contributions of many geologists from various universities and Italian research institutions from the Alps to Sicily. Goethe's Italian journey as revisited in this paper aims to stimulate the interest of the reader in the "geological" component of the environment in which we live by means of an "integrated" approach.

Tectonic and climatic considerations for deep geological disposal of radioactive waste: A UK perspective

International Nuclear Information System (INIS)

McEvoy, F.M.; Schofield, D.I.; Shaw, R.P.; Norris, S.

2016-01-01

Identifying and evaluating the factors that might impact on the long-term integrity of a deep Geological Disposal Facility (GDF) and its surrounding geological and surface environment is central to developing a safety case for underground disposal of radioactive waste. The geological environment should be relatively stable and its behaviour adequately predictable so that scientifically sound evaluations of the long-term radiological safety of a GDF can be made. In considering this, it is necessary to take into account natural processes that could affect a GDF or modify its geological environment up to 1 million years into the future. Key processes considered in this paper include those which result from plate tectonics, such as seismicity and volcanism, as well as climate-related processes, such as erosion, uplift and the effects of glaciation. Understanding the inherent variability of process rates, critical thresholds and likely potential influence of unpredictable perturbations represent significant challenges to predicting the natural environment. From a plate-tectonic perspective, a one million year time frame represents a very short segment of geological time and is largely below the current resolution of observation of past processes. Similarly, predicting climate system evolution on such time-scales, particularly beyond 200 ka AP is highly uncertain, relying on estimating the extremes within which climate and related processes may vary with reasonable confidence. The paper highlights some of the challenges facing a deep geological disposal program in the UK to review understanding of the natural changes that may affect siting and design of a GDF. - Highlights: • Natural processes are key to developing a safety case for geological disposal. • Key factors include plate tectonic and climate-mediated processes. • Process variability is a challenge to predicting the natural environment. • We highlight the challenges for geological disposal programs using

Tectonic and climatic considerations for deep geological disposal of radioactive waste: A UK perspective

Energy Technology Data Exchange (ETDEWEB)

McEvoy, F.M., E-mail: fmcevoy@bgs.ac.uk [British Geological Survey, Keyworth, Nottingham NG12 5GG (United Kingdom); Schofield, D.I. [British Geological Survey, Tongwynlais, CF15 7NE (United Kingdom); Shaw, R.P. [British Geological Survey, Keyworth, Nottingham NG12 5GG (United Kingdom); Norris, S. [Radioactive Waste Management Limited, B587, Curie Avenue, Harwell, Didcot OX11 0RH (United Kingdom)

2016-11-15

Identifying and evaluating the factors that might impact on the long-term integrity of a deep Geological Disposal Facility (GDF) and its surrounding geological and surface environment is central to developing a safety case for underground disposal of radioactive waste. The geological environment should be relatively stable and its behaviour adequately predictable so that scientifically sound evaluations of the long-term radiological safety of a GDF can be made. In considering this, it is necessary to take into account natural processes that could affect a GDF or modify its geological environment up to 1 million years into the future. Key processes considered in this paper include those which result from plate tectonics, such as seismicity and volcanism, as well as climate-related processes, such as erosion, uplift and the effects of glaciation. Understanding the inherent variability of process rates, critical thresholds and likely potential influence of unpredictable perturbations represent significant challenges to predicting the natural environment. From a plate-tectonic perspective, a one million year time frame represents a very short segment of geological time and is largely below the current resolution of observation of past processes. Similarly, predicting climate system evolution on such time-scales, particularly beyond 200 ka AP is highly uncertain, relying on estimating the extremes within which climate and related processes may vary with reasonable confidence. The paper highlights some of the challenges facing a deep geological disposal program in the UK to review understanding of the natural changes that may affect siting and design of a GDF. - Highlights: • Natural processes are key to developing a safety case for geological disposal. • Key factors include plate tectonic and climate-mediated processes. • Process variability is a challenge to predicting the natural environment. • We highlight the challenges for geological disposal programs using

Geologic framework and Cenozoic evolution of the Yucca Mountain area, Nevada

International Nuclear Information System (INIS)

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

1990-01-01

Yucca Mountain, Nevada, has been proposed as the site of a high-level nuclear waste repository. The purpose of this paper is to outline aspects of the geology and tectonics of the area which bear on its suitability as a waste repository. The repository is to be excavated from a non-lithophysal zone within the lower part of the Paintbrush Tuff. Revised estimates of the thickness of this zone indicate that the lower, down-dip extremity of the planned repository could be raised by as much as 130 m, thus reducing the grade within the repository and increasing the distance to the water table below. We note that because of the closely spaced fracturing and low in-situ stresses within the repository block, lateral support of fractured rock is likely to be poor. 30 refs., 5 figs

Identification of scenarios in the safety assessment of a deep geological site for radioactive waste disposal

International Nuclear Information System (INIS)

Escalier des Orres, P.; Devillers, C.; Cernes, A.

1990-01-01

The selection and qualification procedure of a site for radioactive wastes disposal in a deep geologic formation, has begun in France in the early eighties. The public authorities, on ANDRA's proposal, has preselected in 1987 four sites, each of them corresponding to a type of geologic formations (granite, clay, salt and shale). Within two years, one of these sites will be chosen for the location of an underground laboratory. The safety analysis for the site's qualification uses evolution scenarios of the repository and its environment, chosen according to a deterministic method. With an appropriate detail level, are defined a reference scenario and scenario with random events. 4 refs., 1 tab [fr

Groundwater drought in different geological conditions

International Nuclear Information System (INIS)

Machlica, A; Stojkovova, M

2008-01-01

The identification of hydrological extremes (drought) is very actual at present. The knowledge of the mechanism of hydrological extremes evolution could be useful at many levels of human society, such as scientific, agricultural, local governmental, political and others. The research was performed in the Upper part of the Nitra River catchment (central part of Slovakia) and in the Topla and Ondava River catchments (eastern part of Slovakia). Lumped hydrological model BILAN was used to identify relationships among compounds of the water balance. Presented results are focused on drought in groundwater storage, soil moisture, base flow and discharges. BFI model for baseflow estimation was used and results were compared with those gained by BILAN model. Another item of the research was to compare results of hydrological balance model application on catchments with different geological conditions.

Geological exploration of Angola from Sumbe to Namibe: A review at the frontier between geology, natural resources and the history of geology

Science.gov (United States)

Masse, Pierre; Laurent, Olivier

2016-01-01

This paper provides a review of the Geological exploration of the Angola Coast (from Sumbe to Namibe) from pioneer's first geological descriptions and mining inventory to the most recent publications supported by the oil industry. We focus our attention on the following periods: 1875-1890 (Paul Choffat's work, mainly), 1910-1949 (first maps at country scale), 1949-1974 (detailed mapping of the Kwanza-Namibe coastal series), 1975-2000, with the editing of the last version of the Angola geological map at 1:1 million scale and the progressive completion of previous works. Since 2000, there is a renewal in geological fieldwork publications on the area mainly due to the work of university teams. This review paper thus stands at the frontier between geology, natural resources and the history of geology. It shows how geological knowledge has progressed in time, fueled by economic and scientific reasons.

The Geologic Nitrogen Cycle

Science.gov (United States)

Johnson, B. W.; Goldblatt, C.

2013-12-01

N2 is the dominant gas in Earth's atmosphere, and has been so through the majority of the planet's history. Originally thought to only be cycled in significant amounts through the biosphere, it is becoming increasingly clear that a large degree of geologic cycling can occur as well. N is present in crustal rocks at 10s to 100s of ppm and in the mantle at 1s to perhaps 10s of ppm. In light of new data, we present an Earth-system perspective of the modern N cycle, an updated N budget for the silicate Earth, and venture to explain the evolution of the N cycle over time. In an fashion similar to C, N has a fast, biologically mediated cycle and a slower cycle driven by plate tectonics. Bacteria fix N2 from the atmosphere into bioavailable forms. N is then cycled through the food chain, either by direct consumption of N-fixing bacteria, as NH4+ (the primary waste form), or NO3- (the most common inorganic species in the modern ocean). Some organic material settles as sediment on the ocean floor. In anoxic sediments, NH4+ dominates; due to similar ionic radii, it can readily substitute for K+ in mineral lattices, both in sedimentary rocks and in oceanic lithosphere. Once it enters a subduction zone, N may either be volatilized and returned to the atmosphere at arc volcanoes as N2 or N2O, sequestered into intrusive igneous rocks (as NH4+?), or subducted deep into the mantle, likely as NH4+. Mounting evidence indicates that a significant amount of N may be sequestered into the solid Earth, where it may remain for long periods (100s m.y.) before being returned to the atmosphere/biosphere by volcanism or weathering. The magnitude fluxes into the solid Earth and size of geologic N reservoirs are poorly constrained. The size of the N reservoirs contained in the solid Earth directly affects the evolution of Earth's atmosphere. It is possible that N now sequestered in the solid Earth was once in the atmosphere, which would have resulted in a higher atmospheric pressure, and

Quantifying uncertainty of geological 3D layer models, constructed with a-priori geological expertise

NARCIS (Netherlands)

Gunnink, J.J.; Maljers, D.; Hummelman, J.

2010-01-01

Uncertainty quantification of geological models that are constructed with additional geological expert-knowledge is not straightforward. To construct sound geological 3D layer models we use a lot of additional knowledge, with an uncertainty that is hard to quantify. Examples of geological expert

How semantics can inform the geological mapping process and support intelligent queries

Science.gov (United States)

Lombardo, Vincenzo; Piana, Fabrizio; Mimmo, Dario

2017-04-01

The geologic mapping process requires the organization of data according to the general knowledge about the objects, namely the geologic units, and to the objectives of a graphic representation of such objects in a map, following an established model of geotectonic evolution. Semantics can greatly help such a process in two concerns: the provision of a terminological base to name and classify the objects of the map; on the other, the implementation of a machine-readable encoding of the geologic knowledge base supports the application of reasoning mechanisms and the derivation of novel properties and relations about the objects of the map. The OntoGeonous initiative has built a terminological base of geological knowledge in a machine-readable format, following the Semantic Web tenets and the Linked Data paradigm. The major knowledge sources of the OntoGeonous initiative are GeoScience Markup Language schemata and vocabularies (through its last version, GeoSciML 4, 2015, published by the IUGS CGI Commission) and the INSPIRE "Data Specification on Geology" directives (an operative simplification of GeoSciML, published by INSPIRE Thematic Working Group Geology of the European Commission). The Linked Data paradigm has been exploited by linking (without replicating, to avoid inconsistencies) the already existing machine-readable encoding for some specific domains, such as the lithology domain (vocabulary Simple Lithology) and the geochronologic time scale (ontology "gts"). Finally, for the upper level knowledge, shared across several geologic domains, we have resorted to NASA SWEET ontology. The OntoGeonous initiative has also produced a wiki that explains how the geologic knowledge has been encoded from shared geoscience vocabularies (https://www.di.unito.it/wikigeo/). In particular, the sections dedicated to axiomatization will support the construction of an appropriate data base schema that can be then filled with the objects of the map. This contribution will discuss

Geologic Map of the MTM -30262 and -30267 Quadrangles, Hadriaca Patera Region of Mars

Science.gov (United States)

Crown, David A.; Greeley, Ronald

2007-01-01

Introduction Mars Transverse Mercator (MTM) -30262 and -30267 quadrangles cover the summit region and east margin of Hadriaca Patera, one of the Martian volcanoes designated highland paterae. MTM -30262 quadrangle includes volcanic deposits from Hadriaca Patera and Tyrrhena Patera (summit northeast of map area) and floor deposits associated with the Dao and Niger Valles canyon systems (south of map area). MTM -30267 quadrangle is centered on the caldera of Hadriaca Patera. The highland paterae are among the oldest, central-vent volcanoes on Mars and exhibit evidence for explosive eruptions, which make a detailed study of their geology an important component in understanding the evolution of Martian volcanism. Photogeologic mapping at 1:500,000-scale from analysis of Viking Orbiter images complements volcanological studies of Hadriaca Patera, geologic investigations of the other highland paterae, and an analysis of the styles and evolution of volcanic activity east of Hellas Planitia in the ancient, cratered highlands of Mars. This photogeologic study is an extension of regional geologic mapping east of Hellas Planitia. The Martian highland paterae are low-relief, areally extensive volcanoes exhibiting central calderas and radial channels and ridges. Four of these volcanoes, Hadriaca, Tyrrhena, Amphitrites, and Peneus Paterae, are located in the ancient cratered terrains surrounding Hellas Planitia and are thought to be located on inferred impact basin rings or related fractures. Based on analyses of Mariner 9 images, Potter (1976), Peterson (1977), and King (1978) suggested that the highland paterae were shield volcanoes formed by eruptions of fluid lavas. Later studies noted morphologic similarities between the paterae and terrestrial ash shields and the lack of primary lava flow features on the flanks of the volcanoes. The degraded appearances of Hadriaca and Tyrrhena Paterae and the apparently easily eroded materials composing their low, broad shields further

Genetic and geological classification wetlands proposed. Application to the spanish wetlands included in the Ramsar convention; Propuesta de clasificacion genetico-geologica de humedales. Aplicacion a los humedales espanoles incluidos en el Convenio de Ramsar

Energy Technology Data Exchange (ETDEWEB)

Duran Valsero, J. J.; Garcia de Domingo, A.; Robledo Ardila, P.

2009-07-01

The classification represents the first step in the research of the wetlands. There are several types of classifications established according different criteria: geographic, genetic, geologic, functional, hydric, biologic and others. In this work we considered the genetic and geologic classifications criteria are the more suitable because the criteria used are very concrete, descriptive and its application should be easier to put into practice. Every group established in this type of classification determines the develop naturals conditions allowing us to establish the evolution guidelines and same main management lines. The criteria used to develop this classification have been fundamentally: geologic, geomorphologic, tectonics, stratigraphic, and hydrogeologic because these determine greatly the physical wetland characteristics (geometric parameters, hydric nourishment system, hydrochemical characteristics and others). The general characteristics, guidelines behavior of the wetland, and the early evolution of every group of wetland could be essentials to detect and identified those actuations modifying the natural evolution in each concrete wetland. In this work we are applying these classification criteria to the Spanish wetlands included in the Ramsar Convention (until February 2006), defining twelve types of basic wetlands according the geologic and genetic characteristics. (Author) 19 refs.

Asteroids astronomical and geological bodies

CERN Document Server

Burbine, Thomas H

2016-01-01

Asteroid science is a fundamental topic in planetary science and is key to furthering our understanding of planetary formation and the evolution of the Solar System. Ground-based observations and missions have provided a wealth of new data in recent years, and forthcoming missions promise further exciting results. This accessible book presents a comprehensive introduction to asteroid science, summarising the astronomical and geological characteristics of asteroids. The interdisciplinary nature of asteroid science is reflected in the broad range of topics covered, including asteroid and meteorite classification, chemical and physical properties of asteroids, observational techniques, cratering, and the discovery of asteroids and how they are named. Other chapters discuss past, present and future space missions and the threat that these bodies pose for Earth. Based on an upper-level course on asteroids and meteorites taught by the author, this book is ideal for students, researchers and professional scientists ...

The intercrater plains of Mercury and the Moon: Their nature, origin and role in terrestrial planet evolution: Introduction. Ph.D. Thesis

Science.gov (United States)

Leake, M. A.

1982-01-01

The relative ages of various geologic units and structures place tight constraints on the origin of the Moon and the planet Mercury, and thus provide a better understanding of the geologic histories of these bodies. Crater statistics, a reexamination of lunar geologic maps, and the compilation of a geologic map of a quarter of Mercury's surface based on plains units dated relative to crater degradation classes were used to determine relative ages. This provided the basis for deducing the origin of intercrater plains and their role in terrestrial planet evolution.

Facing future climate change: is the past relevant?

Science.gov (United States)

Skinner, Luke

2008-12-28

From a socio-economic perspective, the 'sharp end' of climate research is very much about looking forward in time. As far as possible, we need to know what to expect and approximately when to expect it. However, it is argued here that our approach to climate change (including its scientific basis and its policy implications) is firmly linked to our understanding of the past. This is mainly due to the role played by palaeoclimate reconstructions in shaping our expectations of the climate system, in particular via their ability to test the accuracy of our climate models. Importantly, this includes the intuitive models that each of us carries around in our mind, as well as the more complex numerical models hiding inside supercomputers. It is through such models that palaeoclimate insights may affect the scientific and political judgements that we must make in the face of persistent and ultimately irreducible predictive uncertainty. Already we can demonstrate a great deal of confidence in our current understanding of the global climate system based specifically on insights from the geological record. If further advances are to be made effectively, climate models should take advantage of both past and present constraints on their behaviour, and should be given added credence to the extent that they are compatible with an increasingly rich tapestry of past climatic phenomena. Furthermore, palaeoclimate data should be accompanied by clearly defined uncertainties, and organized in arrays that are capable of speaking directly to numerical models, and their limitations in particular.

Tectonic and climatic considerations for deep geological disposal of radioactive waste: A UK perspective.

Science.gov (United States)

McEvoy, F M; Schofield, D I; Shaw, R P; Norris, S

2016-11-15

Identifying and evaluating the factors that might impact on the long-term integrity of a deep Geological Disposal Facility (GDF) and its surrounding geological and surface environment is central to developing a safety case for underground disposal of radioactive waste. The geological environment should be relatively stable and its behaviour adequately predictable so that scientifically sound evaluations of the long-term radiological safety of a GDF can be made. In considering this, it is necessary to take into account natural processes that could affect a GDF or modify its geological environment up to 1millionyears into the future. Key processes considered in this paper include those which result from plate tectonics, such as seismicity and volcanism, as well as climate-related processes, such as erosion, uplift and the effects of glaciation. Understanding the inherent variability of process rates, critical thresholds and likely potential influence of unpredictable perturbations represent significant challenges to predicting the natural environment. From a plate-tectonic perspective, a one million year time frame represents a very short segment of geological time and is largely below the current resolution of observation of past processes. Similarly, predicting climate system evolution on such time-scales, particularly beyond 200ka AP is highly uncertain, relying on estimating the extremes within which climate and related processes may vary with reasonable confidence. The paper highlights some of the challenges facing a deep geological disposal program in the UK to review understanding of the natural changes that may affect siting and design of a GDF. Crown Copyright © 2016. Published by Elsevier B.V. All rights reserved.

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.

3D Geological Mapping - uncovering the subsurface to increase environmental understanding

Science.gov (United States)

Kessler, H.; Mathers, S.; Peach, D.

2012-12-01

Geological understanding is required for many disciplines studying natural processes from hydrology to landscape evolution. The subsurface structure of rocks and soils and their properties occupies three-dimensional (3D) space and geological processes operate in time. Traditionally geologists have captured their spatial and temporal knowledge in 2 dimensional maps and cross-sections and through narrative, because paper maps and later two dimensional geographical information systems (GIS) were the only tools available to them. Another major constraint on using more explicit and numerical systems to express geological knowledge is the fact that a geologist only ever observes and measures a fraction of the system they study. Only on rare occasions does the geologist have access to enough real data to generate meaningful predictions of the subsurface without the input of conceptual understanding developed from and knowledge of the geological processes responsible for the deposition, emplacement and diagenesis of the rocks. This in turn has led to geology becoming an increasingly marginalised science as other disciplines have embraced the digital world and have increasingly turned to implicit numerical modelling to understand environmental processes and interactions. Recent developments in geoscience methodology and technology have gone some way to overcoming these barriers and geologists across the world are beginning to routinely capture their knowledge and combine it with all available subsurface data (of often highly varying spatial distribution and quality) to create regional and national geological three dimensional geological maps. This is re-defining the way geologists interact with other science disciplines, as their concepts and knowledge are now expressed in an explicit form that can be used downstream to design process models structure. For example, groundwater modellers can refine their understanding of groundwater flow in three dimensions or even directly

The JAERI program for development of safety assessment models and acquisition of data needed for assessment of geological disposal of high-level radioactive wastes

International Nuclear Information System (INIS)

Matsuzuru, H.

1991-01-01

The JAERI is conducting R and D program for the development of safety assessment methodologies and the acquisition of data needed for the assessment of geologic disposal of high-level radioactive wastes, aiming at the elucidation of feasibility of geologic disposal in Japan. The paper describes current R and D activities to develop interim versions of both a deterministic and a probabilistic methodologies based on a normal evolution scenario, to collect data concerning engineered barriers and geologic media through field and laboratory experiments, and to validate the models used in the methodologies. 2 figs., 2 refs

Geological Services Laboratory

Data.gov (United States)

Federal Laboratory Consortium — Researchers use computed tomography (CT) scanners at NETL’s Geological Services Laboratory in Morgantown, WV, to peer into geologic core samples to determine how...

Geology of Mars

International Nuclear Information System (INIS)

Soderblom, L.A.

1988-01-01

The geology of Mars and the results of the Mariner 4, 6/7, and 9 missions and the Viking mission are reviewed. The Mars chronology and geologic modification are examined, including chronological models for the inactive planet, the active planet, and crater flux. The importance of surface materials is discussed and a multispectral map of Mars is presented. Suggestions are given for further studies of the geology of Mars using the Viking data. 5 references

Geochemical investigation of groundwater in the Tono area, Japan. Chemical characteristics and groundwater evolution

International Nuclear Information System (INIS)

Iwatsuki, Teruki; Hama, Katsuhiro; Yoshida, Hidekazu

1997-01-01

Geochemical investigations form an important part of the R and D program at the Tono study site, central Japan. Detailed geological structure and groundwater chemistry have been studied to understand the geochemical environment in the sedimentary and crystalline rocks distributed in this area. The chemical evolution of the groundwater in the sedimentary rocks is characterized with the variation in Na + , Ca 2+ and HCO 3 - concentrations, and ion exchange and dissolution of calcite are dominant reactions in the evolution of groundwater. Geological investigation shows that a fracture system of crystalline rock can be classified into:intact zone, moderately fractured zone and intensely fractured zone, according to the frequency and the width of fractures and fractured zones. The groundwater in the intact and fractured zones of crystalline rock are characterized by Na + -Ca 2+ -HCO 3 - or Na + -HCO 3 - dominated water, and Na + -Ca 2+ -Fe 2+ -HCO 3 - dominated water. The chemical evolution of groundwater is, generally, controlled by water-rock interaction between plagioclase, iron minerals and groundwater. The groundwater at depth of G.L.-186m in the crystalline rock at the Tono area is characterized by the mixture between the oxidized surface water and the reduced groundwater. The investigation based on correlation between geological structures and groundwater chemistry can be applied to understand the geochemical environment in deep crystalline rock, and will support the development of a realistic hydrogeochemical model. (author)

History of geological disposal concept (3). Implementation phase of geological disposal (2000 upward)

International Nuclear Information System (INIS)

Masuda, Sumio; Sakuma, Hideki; Umeki, Hiroyuki

2015-01-01

Important standards and concept about geological disposal have been arranged as an international common base and are being generalized. The authors overview the concept of geological disposal, and would like this paper to help arouse broad discussions for promoting the implementation plan of geological disposal projects in the future. In recent years, the scientific and technological rationality of geological disposal has been recognized internationally. With the addition of discussions from social viewpoints such as ethics, economy, etc., geological disposal projects are in the stage of starting after establishment of social consensus. As an international common base, the following consolidated and systematized items have been presented as indispensable elements in promoting business projects: (1) step-by-step approach, (2) safety case, (3) reversibility and recovery potential, and (4) trust building and communications. This paper outlines the contents of the following cases, where international common base was reflected on the geological disposal projects in Japan: (1) final disposal method and safety regulations, and (2) impact of the Great East Japan Earthquake and Fukushima Daiichi Nuclear Power Station accident on geological disposal plan. (A.O.)

Evolution of the basalts from three back-arc basins of southwest Pacific

Digital Repository Service at National Institute of Oceanography (India)

Mudholkar, A.V.; Paropkari, A.L.

London: Blackie, pp 63}93 Parson LM, Pearce JA, Murton BJ, Hodkinson RA, and RRS Charles Darwin Scienti"c Party (1990) Role of ridge jumps and ridge propagation in the tectonic evolution of the Lau back-arc basin, southwest Paci"c. Geology, 18:470}473 Per...

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.

Geology's Impact on Culture

Science.gov (United States)

Pizzorusso, Ann

2017-04-01

Most people consider geology boring, static and difficult. The fields of astronomy and physics have "rebranded" themselves with exciting programs formatted so as to be readily understandable to the general public. The same thing can be done for geology. My research on geology's influence on other disciplines has resulted in a book, Tweeting da Vinci, in which I was able to show how geology affected Italy's art, architecture, medicine, religion, literature, engineering and just about everything else. The reaction to the book and my lectures by both students and the general public has been very positive, including four gold medals, with reviews and comments indicating that they never knew geology could be so exciting. The book is very user friendly, packed with facts, full-color photos, paintings, sketches and illustrations. Complex aspects of geology are presented in an easily understandable style. Widely diverse topics—such as gemology, folk remedies, grottoes, painting, literature, physics and religion—are stitched together using geology as a thread. Quoting everyone from Pliny the Elder to NASA physicist Friedemann Freund, the work is solidly backed scholarship that reads as easily as a summer novel. The book can be used in classes such as physics, chemistry, literature, art history, medicine, Classical Studies, Latin, Greek and Italian. By incorporating a "geologic perspective" in these courses, it can be perceived as a more "all encompassing" discipline and encourage more students to study it. The lectures I have given on college campuses have resulted in students seeing their own majors from a different perspective and some have even signed up for introductory geology courses. One college organized summer course to the Bay of Naples based on the book. We followed the geology as well as the culture of the area and the students were profoundly moved. To encourage dialog, the book is linked to Facebook, Twitter and Instagram. This has enabled followers from

Isotopic and geochemical evolution of ground and surface waters in a karst dominated geological setting: a case study from Belize, Central America

International Nuclear Information System (INIS)

Marfia, A.M.; Krishnamurthy, R.V.; Atekwana, E.A.; Panton, W.F.

2004-01-01

Analysis of stable isotopes and major ions in groundwater and surface waters in Belize, Central America was carried out to identify processes that may affect drinking water quality. Belize has a subtropical rainforest/savannah climate with a varied landscape composed predominantly of carbonate rocks and clastic sediments. Stable oxygen (δ 18 O) and hydrogen (δD) isotope ratios for surface and groundwater have a similar range and show high d-excess (10-40.8%o). The high d-excess in water samples suggest secondary continental vapor flux mixing with incoming vapor from the Caribbean Sea. Model calculations indicate that moisture derived from continental evaporation contributes 13% to overhead vapor load. In surface and groundwater, concentrations of dissolved inorganic carbon (DIC) ranged from 5.4 to 112.9 mg C/l and δ 13 C DIC ranged from -7.4 to -17.4%o. SO 4 2 , Ca 2+ and Mg 2+ in the water samples ranged from 2-163, 2-6593 and 2-90 mg/l, respectively. The DIC and δ 13 C DIC indicate both open and closed system carbonate evolution. Combined δ 13 C DIC and Ca 2+ , Mg 2+ , and SO 4 2- suggest additional groundwater evolution by gypsum dissolution and calcite precipitation. The high SO 4 2- content of some water samples indicates regional geologic control on water quality. Similarity in the range of δ 18 O, δD and δ 13 C DIC for surface waters and groundwater used for drinking water supply is probably due to high hydraulic conductivities of the karstic aquifers. The results of this study indicate rapid recharge of groundwater aquifers, groundwater influence on surface water chemistry and the potential of surface water to impact groundwater quality and vise versa

Environmental geology and hydrology

Science.gov (United States)

Nakić, Zoran; Mileusnić, Marta; Pavlić, Krešimir; Kovač, Zoran

2017-10-01

Environmental geology is scientific discipline dealing with the interactions between humans and the geologic environment. Many natural hazards, which have great impact on humans and their environment, are caused by geological settings. On the other hand, human activities have great impact on the physical environment, especially in the last decades due to dramatic human population growth. Natural disasters often hit densely populated areas causing tremendous death toll and material damage. Demand for resources enhanced remarkably, as well as waste production. Exploitation of mineral resources deteriorate huge areas of land, produce enormous mine waste and pollute soil, water and air. Environmental geology is a broad discipline and only selected themes will be presented in the following subchapters: (1) floods as natural hazard, (2) water as geological resource and (3) the mining and mineral processing as types of human activities dealing with geological materials that affect the environment and human health.

The determination of initial ratio of strontium isotope in rocks and its geological application

International Nuclear Information System (INIS)

Ying Junlong; Zhao Puyun; Lin Xiulan

1989-04-01

The method to determine the initial ratio of strontium isotopes existed in rocks of poor rubidium and rich strontium and main carrier minerals is introduced. The initial ratio obtained from this method is equivalent to that acquired by Rb-Sr isochrone. Based on this result, information on regional rock genesis and mineralization regularities can be provided. It has great significance in the research on activities of ancient continental margin and material sources as well as their evolution. The migration of rock, and ore-forming materials, matallogenetic mechanism and its distribution in the space and time evolution are studied by using these data. In conclusion, the determination of strontium isotopes has broad prospects in the geological research

Radar, geologic, airborne gamma ray and Landsat TM digital data integration for geological mapping of the Estrela granite complex (Para State)

International Nuclear Information System (INIS)

Cunha, Edson Ricardo Soares Pereira da

2002-01-01

This work is focused on the geotectonic context of the Carajas Mineral Province, Amazon Craton, which represents the most important Brazilian Mineral Province and hosts iron, cooper, gold, manganese and nickel deposits. At the end of Archean age, during the techno-metamorphic evolution, moderated alkaline granitoids were generated, such as, Estrela Granite Complex (EGC). This work has used digital integration products with the purpose of study the granite suite, its host rock, and the surrounded area. The digital integrated data were gamma-ray and geological data with satellite images (SAR-SAREX e TM-Landsat). The geophysics data, originally in 32 bits and grid format, were interpolated and converted to 8 bits images. The geological data (facies map) was digitalized and converted to a raster format. The remote sensing images were geometrically corrected to guarantee an accuracy on the geological mapping. On the data processing phase, SAR images were digital integrated with gamma-ray data, TM-Landsat image and the raster facies map. The IHS transformation was used as the technique to integrate the multi-source data. On the photogeological interpretation, SAR data were extremely important to permit the extraction of the main tectonic lineaments which occur on the following directions: +/- N45W, +/- N70W, +/- NS, +/- N20E, +/- N45E e +/- N75E. This procedure was done both in analogic and automatic form, being the automatic process more useful to complement information in the extracting process. Among the digital products generated, SAR/GAMA products (uranium, thorium and total count) were the ones that give the most important contribution. The interpretation of the SAR/GAMA's products added to the field campaign have allowed to map the limits of units that occur in the region and four facies of the Estrela Granite Complex were detected. The origin of the granite suite might be related to a magmatic differentiation or to distinct intrusion pulses. The use of the

Geologic Time.

Science.gov (United States)

Newman, William L.

One of a series of general interest publications on science topics, the booklet provides those interested in geologic time with an introduction to the subject. Separate sections discuss the relative time scale, major divisions in geologic time, index fossils used as guides for telling the age of rocks, the atomic scale, and the age of the earth.…

Sedimentary Geology Context and Challenges for Cyberinfrastructure Data Management

Science.gov (United States)

Chan, M. A.; Budd, D. A.

2014-12-01

A cyberinfrastructure data management system for sedimentary geology is crucial to multiple facets of interdisciplinary Earth science research, as sedimentary systems form the deep-time framework for many geoscience communities. The breadth and depth of the sedimentary field spans research on the processes that form, shape and affect the Earth's sedimentary crust and distribute resources such as hydrocarbons, coal, and water. The sedimentary record is used by Earth scientists to explore questions such as the continental crust evolution, dynamics of Earth's past climates and oceans, evolution of the biosphere, and the human interface with Earth surface processes. Major challenges to a data management system for sedimentary geology are the volume and diversity of field, analytical, and experimental data, along with many types of physical objects. Objects include rock samples, biological specimens, cores, and photographs. Field data runs the gamut from discrete location and spatial orientation to vertical records of bed thickness, textures, color, sedimentary structures, and grain types. Ex situ information can include geochemistry, mineralogy, petrophysics, chronologic, and paleobiologic data. All data types cover multiple order-of-magnitude scales, often requiring correlation of the multiple scales with varying degrees of resolution. The stratigraphic framework needs dimensional context with locality, time, space, and depth relationships. A significant challenge is that physical objects represent discrete values at specific points, but measured stratigraphic sections are continuous. In many cases, field data is not easily quantified, and determining uncertainty can be difficult. Despite many possible hurdles, the sedimentary community is anxious to embrace geoinformatic resources that can provide better tools to integrate the many data types, create better search capabilities, and equip our communities to conduct high-impact science at unprecedented levels.

OneGeology-Europe: architecture, portal and web services to provide a European geological map

Science.gov (United States)

Tellez-Arenas, Agnès.; Serrano, Jean-Jacques; Tertre, François; Laxton, John

2010-05-01

OneGeology-Europe is a large ambitious project to make geological spatial data further known and accessible. The OneGeology-Europe project develops an integrated system of data to create and make accessible for the first time through the internet the geological map of the whole of Europe. The architecture implemented by the project is web services oriented, based on the OGC standards: the geological map is not a centralized database but is composed by several web services, each of them hosted by a European country involved in the project. Since geological data are elaborated differently from country to country, they are difficult to share. OneGeology-Europe, while providing more detailed and complete information, will foster even beyond the geological community an easier exchange of data within Europe and globally. This implies an important work regarding the harmonization of the data, both model and the content. OneGeology-Europe is characterised by the high technological capacity of the EU Member States, and has the final goal to achieve the harmonisation of European geological survey data according to common standards. As a direct consequence Europe will make a further step in terms of innovation and information dissemination, continuing to play a world leading role in the development of geosciences information. The scope of the common harmonized data model was defined primarily by the requirements of the geological map of Europe, but in addition users were consulted and the requirements of both INSPIRE and ‘high-resolution' geological maps were considered. The data model is based on GeoSciML, developed since 2006 by a group of Geological Surveys. The data providers involved in the project implemented a new component that allows the web services to deliver the geological map expressed into GeoSciML. In order to capture the information describing the geological units of the map of Europe the scope of the data model needs to include lithology; age; genesis and

Glaciation and geosphere evolution - Greenland Analogue Project

International Nuclear Information System (INIS)

Hirschorn, S.; Vorauer, A.; Belfadhel, M.B.; Jensen, M.

2011-01-01

The deep geological repository concept for the long-term management of used nuclear fuel involves the containment and isolation of used nuclear fuel in a suitable geological formation. A key objective of the Canadian Nuclear Waste Management Organization (NWMO) geoscience technical research program is to advance the understanding of geosphere stability and its resilience to perturbations over time frames of relevance to a deep geological repository. Glaciation has been identified as the most probable and intense perturbation relevant to a deep geological repository associated with long-term climate change in northern latitudes. Given that the North American continent has been re-glaciated nine times over the past million years, it is strongly expected that a deep geological repository within a suitable crystalline or sedimentary rock formation in Canada will be subject to glaciation events associated with long-term climate change. As such, NWMO's geoscience research program has placed particular emphasis on investigations of the response of the geosphere to glaciations. As surface conditions change from present day conditions to periglacial, followed by ice-sheet cover of variable thickness and rapid glacial retreat, transient geochemical, hydraulic, mechanical and temperature conditions will be simultaneously imposed on groundwater systems. NWMO research activities related to glaciation events and their impacts on groundwater system evolution are being undertaken using a multi-disciplinary approach aimed at collecting multiple lines of evidence. These investigations include assessment of the: Impact of an ice sheet on groundwater composition at repository depth using the Greenland Ice Sheet as an analogue to future glaciations in North America; Expected physical and temporal surface boundary conditions related to potential future glaciation events by estimating the magnitude and time rate of change of ice sheet thickness, ground surface temperature and

Homo Sapiens as Geological Agents

Science.gov (United States)

Holloway, T.; Bedsworth, L. W.; Caldeira, K.; Rosenzweig, C.; Kelley, G.; Rosenzweig, C.; Caldeira, K.; Bedsworth, L. W.; Holloway, T.; Purdy, J. S.; Vince, G.; Syvitski, J. A.; Bondre, N. R.; Kelly, J.; Vince, G.; Seto, K. C.; Steffen, W.; Oreskes, N.

2015-12-01

In the 18th and 19th centuries, earth scientists came to understand the magnitude and power of geological and geophysical processes. In comparison, the activities of humans seemed paltry if not insignificant. With the development of radiometric dating in the 20th century, scientists realized that human history was but a miniscule part of Earth history. Metaphors to this effect abounded, and filled textbooks: If Earth history were a 24-hour day, human history would not occupy even the final second. If Earth history were a yardstick, the human portion would not even be visible to the naked eye. Generations of scientists were taught that one of the principal contributions of geology, qua science, was the demonstration of our insignificance. The Anthropocene concept disrupts this. To affirms its existence is to insist that human activities compete in scale and significance with other Earth processes, and may threaten to overwhelm them. It also inverts our relation to normative claims. For more than a century earth scientists and evolutionary biologists insisted that their theories were descriptive and not normative—that there was no moral conclusion to be drawn from either planetary or human evolution. Now, we confront the suggestion that there is a moral component to our new paradigm: we can scarcely claim that humans are disrupting the climate, destroying biodiversity, and acidifying the oceans without implying that there is something troubling about these developments. Thus, the Anthropocene concept suggests both a radical redefinition of the scope of Earth science, and a radical reconsideration of the place of normative judgments in scientific work.

Lunar exploration: opening a window into the history and evolution of the inner Solar System.

Science.gov (United States)

Crawford, Ian A; Joy, Katherine H

2014-09-13

The lunar geological record contains a rich archive of the history of the inner Solar System, including information relevant to understanding the origin and evolution of the Earth-Moon system, the geological evolution of rocky planets, and our local cosmic environment. This paper provides a brief review of lunar exploration to-date and describes how future exploration initiatives will further advance our understanding of the origin and evolution of the Moon, the Earth-Moon system and of the Solar System more generally. It is concluded that further advances will require the placing of new scientific instruments on, and the return of additional samples from, the lunar surface. Some of these scientific objectives can be achieved robotically, for example by in situ geochemical and geophysical measurements and through carefully targeted sample return missions. However, in the longer term, we argue that lunar science would greatly benefit from renewed human operations on the surface of the Moon, such as would be facilitated by implementing the recently proposed Global Exploration Roadmap. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

Possible environmental effects on the evolution of the Alps-Molasse basin system

International Nuclear Information System (INIS)

Schlunegger, F.; Rieke-Zapp, D.; Ramseyer, K.

2007-01-01

We propose three partly unrelated stages in the geodynamic evolution of the Alps and the sedimentary response of the Molasse Basin. The first stage comprises the time interval between ca. 35 and 20 Ma and is characterized by a high ratio between rates of crustal accretion and surface erosion. The response of the Molasse Basin was a change from the stage of basin underfill (UMM) to overfill (USM). Because the response time of erosional processes to crustal accretion and surface uplift lasts several millions of years, the orogen first experienced a net growth until the end of the Oligocene. As a result, the Molasse basin subsided at high rates causing the topographic axis to shift to the proximal basin border and alluvial fans to establish at the thrust front. During the Aquitanian, however, ongoing erosion and downcutting in the hinterland caused sediment discharge to the basin to increase and the ratio between the rates of crustal accretion and surface erosion to decrease. The result was a progradation of the dispersal systems, and a shift of the topographic axis towards the distal basin border. The second stage started at ca. 20 Ma at a time when palaeoclimate became more continental, and when the crystalline core became exposed in the orogen. The effect was a decrease in the erosional efficiency of the Swiss Alps and hence a reduction of sediment discharge to the Molasse Basin. We propose that this decrease in sediment flux caused the Burdigalian transgression of the OMM. We also speculate that this reduction of surface erosion initiated the modification of Alpine deformation from vertically- to mainly horizontally directed extrusion (deformation of the Southern Alps, and the Jura Mountains some Ma later). The third stage in the geodynamic development was initiated at the Miocene/Pliocene boundary. At that time, palaeoclimate possibly became wetter, which, in turn, caused surface erosion to increase relative to crustal accretion. This change caused the Alps to

Aerogeophysical survey over Sør Rondane Mountains and its implications for revealing the tectonic evolution of East Antarctica

Science.gov (United States)

Mieth, Matthias; Steinhage, Daniel; Ruppel, Antonia; Damaske, Detlef; Jokat, Wilfried

2013-04-01

We are presenting new magnetic and gravity data of a high-resolution aerogephysical survey over the area of the Sør Rondane Mountains in the eastern Dronning Maud Land (DML). The aircraft survey is part of the joint geological and geophysical GEA campaign (Geodynamic Evolution of East Antarctica) of the Federal Agency for Geosciences and Natural Resources (BGR) and Alfred-Wegener-Institute for Polar and Marine Research (AWI), in cooperation with the Universities of Ghent, Bremen and Bergen. It was completed during the Antarctic summer season 2012/13, covering an area of more than 100000 square kilometer with a line spacing of 5 km. The data will be correlated with geological structures exposed in the mountain range as well as matched and merged with the data sets of the eastern and southern DML (acquired by AWI during the last decade) for comparison and discussion in the greater context of the tectonic evolution of East Antarctica. Preliminary results show that the magnetic anomaly pattern over the Sør Rondane Mountains differs from the pattern found over the central DML mountains as well as from the low amplitude pattern in between both regions, indicating a significant difference in the evolution of this region, which is in accordance with latest geological findings in this region.

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

In 1960, the U.S. Geological Survey and the Kentucky Geological Survey began a program to map the State geologically at a scale of 1:24,000 and to publish the maps as 707 U.S. Geological Survey Geologic Quadrangle Maps. Fieldwork was completed by the spring of 1977, and all maps were published by December 1978. Geologic mapping of the State was proposed by the Kentucky Society of Professional Engineers in 1959. Wallace W. Hagan, Director and State Geologist of the Kentucky Geological Survey, and Preston McGrain, Assistant State Geologist, promoted support for the proposal among organizations such as Chambers of Commerce, industrial associations, professional societies, and among members of the State government. It was also arranged for the U.S. Geological Survey to supply mapping personnel and to publish the maps; the cost would be shared equally by the two organizations. Members of the U.S. Geological Survey assigned to the program were organized as the Branch of Kentucky Geology. Branch headquarters, including an editorial staff, was at Lexington, Ky., but actual mapping was conducted from 18 field offices distributed throughout the State. The Publications Division of the U.S. Geological Survey established a cartographic office at Lexington to prepare the maps for publication. About 260 people, including more than 200 professionals, were assigned to the Branch of Kentucky Geology by the U.S. Geological Survey at one time or another. The most geologists assigned any one year was 61. To complete the mapping and ancillary studies, 661 professional man-years were required, compared with an original estimate of 600 man-years. A wide variety of field methods were used, but most geologists relied on the surveying altimeter to obtain elevations. Surface data were supplemented by drill-hole records, and several dozen shallow diamond-drill holes were drilled to aid the mapping. Geologists generally scribed their own maps, with a consequent saving of publication costs

Geologic Framework Model (GFM2000)

International Nuclear Information System (INIS)

T. Vogt

2004-01-01

The purpose of this report is to document the geologic framework model, version GFM2000 with regard to input data, modeling methods, assumptions, uncertainties, limitations, and validation of the model results, and the differences between GFM2000 and previous versions. The version number of this model reflects the year during which the model was constructed. This model supersedes the previous model version, documented in Geologic Framework Model (GFM 3.1) (CRWMS M and O 2000 [DIRS 138860]). The geologic framework model represents a three-dimensional interpretation of the geology surrounding the location of the monitored geologic repository for spent nuclear fuel and high-level radioactive waste at Yucca Mountain. The geologic framework model encompasses and is limited to an area of 65 square miles (168 square kilometers) and a volume of 185 cubic miles (771 cubic kilometers). The boundaries of the geologic framework model (shown in Figure 1-1) were chosen to encompass the exploratory boreholes and to provide a geologic framework over the area of interest for hydrologic flow and radionuclide transport modeling through the unsaturated zone (UZ). The upper surface of the model is made up of the surface topography and the depth of the model is constrained by the inferred depth of the Tertiary-Paleozoic unconformity. The geologic framework model was constructed from geologic map and borehole data. Additional information from measured stratigraphic sections, gravity profiles, and seismic profiles was also considered. The intended use of the geologic framework model is to provide a geologic framework over the area of interest consistent with the level of detailed needed for hydrologic flow and radionuclide transport modeling through the UZ and for repository design. The model is limited by the availability of data and relative amount of geologic complexity found in an area. The geologic framework model is inherently limited by scale and content. The grid spacing used in

Geologic Framework Model (GFM2000)

Energy Technology Data Exchange (ETDEWEB)

T. Vogt

2004-08-26

The purpose of this report is to document the geologic framework model, version GFM2000 with regard to input data, modeling methods, assumptions, uncertainties, limitations, and validation of the model results, and the differences between GFM2000 and previous versions. The version number of this model reflects the year during which the model was constructed. This model supersedes the previous model version, documented in Geologic Framework Model (GFM 3.1) (CRWMS M&O 2000 [DIRS 138860]). The geologic framework model represents a three-dimensional interpretation of the geology surrounding the location of the monitored geologic repository for spent nuclear fuel and high-level radioactive waste at Yucca Mountain. The geologic framework model encompasses and is limited to an area of 65 square miles (168 square kilometers) and a volume of 185 cubic miles (771 cubic kilometers). The boundaries of the geologic framework model (shown in Figure 1-1) were chosen to encompass the exploratory boreholes and to provide a geologic framework over the area of interest for hydrologic flow and radionuclide transport modeling through the unsaturated zone (UZ). The upper surface of the model is made up of the surface topography and the depth of the model is constrained by the inferred depth of the Tertiary-Paleozoic unconformity. The geologic framework model was constructed from geologic map and borehole data. Additional information from measured stratigraphic sections, gravity profiles, and seismic profiles was also considered. The intended use of the geologic framework model is to provide a geologic framework over the area of interest consistent with the level of detailed needed for hydrologic flow and radionuclide transport modeling through the UZ and for repository design. The model is limited by the availability of data and relative amount of geologic complexity found in an area. The geologic framework model is inherently limited by scale and content. The grid spacing used in the

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)

Landscape evolution by subglacial quarrying

DEFF Research Database (Denmark)

Ugelvig, Sofie Vej; Egholm, D.L.; Iverson, Neal R.

In glacial landscape evolution models, subglacial erosion rates are often related to basal sliding or ice discharge by a power-law. This relation can be justified for bedrock abrasion because rock debris transported in the basal ice drives the erosion. However, a simple relation between rates of ...... evolution models. Geology, v. 40, no. 8, 679-682 (2012). Schoof, C. The effect of cavitation on glacier sliding. Proc. R. Soc. A , 461, 609-627 (2005). Jaeger, J.C., and Cook, N.G.W. Fundamentals of rock mechanics: New York, Chapman and Hall, 593 p. (1979)......In glacial landscape evolution models, subglacial erosion rates are often related to basal sliding or ice discharge by a power-law. This relation can be justified for bedrock abrasion because rock debris transported in the basal ice drives the erosion. However, a simple relation between rates...... of sliding and erosion is not well supported when considering models for quarrying of rock blocks from the bed. Iverson (2012) introduced a new subglacial quarrying model that operates from the theory of adhesive wear. The model is based on the fact that cavities, with a high level of bedrock differential...

Geological and geotechnical limitations of radioactive waste retrievability in geologic disposals

Energy Technology Data Exchange (ETDEWEB)

Stahlmann, Joachim; Leon-Vargas, Rocio; Mintzlaff, Volker; Treidler, Ann-Kathrin [TU Braunschweig (Germany). Inst. for Soil Mechanics and Foundation Engineering

2015-07-01

The capability of retrieving radioactive waste emplaced in deep geological formations is nowadays in discussion in many countries. Based on the storage of high-level radioactive waste (HAW) in deep geological repositories there is a number of possible scenarios for their retrieval. Measurements for an improved retrieving capability may impact on the geotechnical and geological barriers, e.g. keeping open the access drifts for a long period of time can result in a bigger evacuation damage zone (EDZ) in the host rock which implies potential flow paths for ground water. Nevertheless, to limit the possible scenarios associated to the retrieval implementation, it is necessary to take in consideration which criteria will be used for an efficient monitoring program, while clearly determining the performance reliability of the geotechnical barriers. In addition, the integrity of the host rock as geological barrier has to be verified. Therefore, it is important to evaluate different design solutions and the most appropriate measurement methods to improve the retrievability process of wastes from a geological repository. A short presentation of the host rocks is given is this paper.

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

The MESSENGER mission to Mercury: new insights into geological processes and evolution

Science.gov (United States)

Head, James W., III; Solomon, Sean C.; McNutt, Ralph L., Jr.; Blewett, David T.; Chapman, Clark R.; Domingue, Deborah L.; Evans, Larry G.; Gillis-Davis, Jeffrey J.; Hawkins, S. Edward, III; Helbert, Jörn; Holsclaw, Gregory M.; Izenberg, Noam R.; McClintock, William E.; McCoy, Timothy J.; Merline, William J.; Murchie, Scott L.; Nittler, Larrz R.; Phillips, Roger J.; Prockter, Louise M.; Robinson, Mark S.; Sprague, Ann L.; Strom, Robert G.; Vilas, Faith; Watters, Thomas R.; Zuber, Maria T.

2008-09-01

The MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) mission, a part of NASA's Discovery Program, was designed to answer six questions [1]: (1) What planetary formational processes led to Mercury's high ratio of metal to silicate? (2) What is the geological history of Mercury? (3) What are the nature and origin of Mercury's magnetic field? (4) What are the structure and state of Mercury's core? (5) What are the radar-reflective materials at Mercury's poles? (6) What are the important volatile species and their sources and sinks near Mercury? MESSENGER is currently midway through a complex interplanetary cruise phase that involves three flybys of Mercury. The first of these, on 14 January 2008, provided important new information relating to several of the questions above [2-13]. Here we summarize observations made during the flyby that are most relevant to new insights about geological processes that have operated on Mercury and implications for the planet's history [3, 8-13]. The instruments that provided the most direct information on the geological history of Mercury during this first encounter were the Mercury Dual Imaging System (MDIS) [14], the Mercury Atmospheric and Surface Composition Spectrometer (MASCS) [15], and the Mercury Laser Altimeter (MLA) [16]. Among the many specific questions remaining following the Mariner 10 mission to Mercury (1974- 1975) were (1) the level of mineralogical and compositional diversity of the crust, which appeared relatively bland in Mariner 10 data, (2) the nature of the rest of the huge Caloris impact basin seen only partially in Mariner 10 images, (3) the origin of the extensive plains observed on the surface (ponded impact ejecta or extrusive lava flows?), (4) the diversity and global distribution of tectonic features that have deformed the crust and their implications for strain as a function of time, and (5) the bombardment chronology and geological history of Mercury [1, 17-19]. The viewing

Regional and site geological frameworks : proposed Deep Geologic Repository, Bruce County, Ontario

Energy Technology Data Exchange (ETDEWEB)

Raven, K.; Sterling, S.; Gaines, S.; Wigston, A. [Intera Engineering Ltd., Ottawa, ON (Canada); Frizzell, R. [Nuclear Waste Management Organization, Toronto, ON (Canada)

2009-07-01

The Nuclear Waste Management Organization is conducting geoscientific studies on behalf of Ontario Power Generation into the proposed development of a Deep Geologic Repository (DGR) for low and intermediate level radioactive waste (L and ILW) at the Bruce site, near Tiverton, Ontario. This paper presented a regional geological framework for the site that was based on a review of regional drilling; structural geology; paleozoic stratigraphy and sedimentology; a 3D geological framework model; a DGR geological site characterization model; bedrock stratigraphy and marker beds; natural fracture frequency data; and formation predictability. The studies have shown that the depth, thickness, orientation and rock quality of the 34 rock formations, members or units that comprise the 840 m thick Paleozoic bedrock sequence at the Bruce site are very uniform and predictable over distances of several kilometres. The proposed DGR will be constructed as an engineered facility comprising a series of underground emplacement rooms at a depth of 680 metres below ground within argillaceous limestones. The geoscientific studies are meant to provide a basis for the development of descriptive geological, hydrogeological and geomechanical models of the DGR site that will facilitate environmental and safety assessments. 11 refs., 3 tabs., 9 figs.

Heterogeneity-enhanced gas phase formation in shallow aquifers during leakage of CO2-saturated water from geologic sequestration sites

Science.gov (United States)

Plampin, Michael R.; Lassen, Rune N.; Sakaki, Toshihiro; Porter, Mark L.; Pawar, Rajesh J.; Jensen, Karsten H.; Illangasekare, Tissa H.

2014-12-01

A primary concern for geologic carbon storage is the potential for leakage of stored carbon dioxide (CO2) into the shallow subsurface where it could degrade the quality of groundwater and surface water. In order to predict and mitigate the potentially negative impacts of CO2 leakage, it is important to understand the physical processes that CO2 will undergo as it moves through naturally heterogeneous porous media formations. Previous studies have shown that heterogeneity can enhance the evolution of gas phase CO2 in some cases, but the conditions under which this occurs have not yet been quantitatively defined, nor tested through laboratory experiments. This study quantitatively investigates the effects of geologic heterogeneity on the process of gas phase CO2 evolution in shallow aquifers through an extensive set of experiments conducted in a column that was packed with layers of various test sands. Soil moisture sensors were utilized to observe the formation of gas phase near the porous media interfaces. Results indicate that the conditions under which heterogeneity controls gas phase evolution can be successfully predicted through analysis of simple parameters, including the dissolved CO2 concentration in the flowing water, the distance between the heterogeneity and the leakage location, and some fundamental properties of the porous media. Results also show that interfaces where a less permeable material overlies a more permeable material affect gas phase evolution more significantly than interfaces with the opposite layering.

Teaching evolution (and all of biology) more effectively: Strategies for engagement, critical reasoning, and confronting misconceptions.

Science.gov (United States)

Nelson, Craig E

2008-08-01

The strength of the evidence supporting evolution has increased markedly since the discovery of DNA but, paradoxically, public resistance to accepting evolution seems to have become stronger. A key dilemma is that science faculty have often continued to teach evolution ineffectively, even as the evidence that traditional ways of teaching are inferior has become stronger and stronger. Three pedagogical strategies that together can make a large difference in students' understanding and acceptance of evolution are extensive use of interactive engagement, a focus on critical thinking in science (especially on comparisons and explicit criteria) and using both of these in helping the students actively compare their initial conceptions (and publicly popular misconceptions) with more fully scientific conceptions. The conclusion that students' misconceptions must be dealt with systematically can be difficult for faculty who are teaching evolution since much of the students' resistance is framed in religious terms and one might be reluctant to address religious ideas in class. Applications to teaching evolution are illustrated with examples that address criteria and critical thinking, standard geology versus flood geology, evolutionary developmental biology versus organs of extreme perfection, and the importance of using humans as a central example. It is also helpful to bridge the false dichotomy, seen by many students, between atheistic evolution versus religious creationism. These applications are developed in detail and are intended to be sufficient to allow others to use these approaches in their teaching. Students and other faculty were quite supportive of these approaches as implemented in my classes.

Assessing correlations between geological hazards and health outcomes: Addressing complexity in medical geology.

Science.gov (United States)

Wardrop, Nicola Ann; Le Blond, Jennifer Susan

2015-11-01

The field of medical geology addresses the relationships between exposure to specific geological characteristics and the development of a range of health problems: for example, long-term exposure to arsenic in drinking water can result in the development of skin conditions and cancers. While these relationships are well characterised for some examples, in others there is a lack of understanding of the specific geological component(s) triggering disease onset, necessitating further research. This paper aims to highlight several important complexities in geological exposures and the development of related diseases that can create difficulties in the linkage of exposure and health outcome data. Several suggested approaches to deal with these complexities are also suggested. Long-term exposure and lengthy latent periods are common characteristics of many diseases related to geological hazards. In combination with long- or short-distance migrations over an individual's life, daily or weekly movement patterns and small-scale spatial heterogeneity in geological characteristics, it becomes problematic to appropriately assign exposure measurements to individuals. The inclusion of supplementary methods, such as questionnaires, movement diaries or Global Positioning System (GPS) trackers can support medical geology studies by providing evidence for the most appropriate exposure measurement locations. The complex and lengthy exposure-response pathways involved, small-distance spatial heterogeneity in environmental components and a range of other issues mean that interdisciplinary approaches to medical geology studies are necessary to provide robust evidence. Copyright © 2015. Published by Elsevier Ltd.

The geological carbon cycle and the global warming / climate debate

International Nuclear Information System (INIS)

Frank, F.

2013-01-01

The extensively cited seasonal carbon cycle describes the size and the annual fluxes between the temporary reservoirs (ocean, atmosphere, biosphere and soils). Compared with these large annual fluxes (approx. 200 GtC/y) the human contribution seems to be of minor amount and is currently (2011) in the range of 4-5%. However, in the geological carbon cycle, which describes the nearly equal amounts of input (volcanoes etc.) and output (sediments) into and from the temporary reservoirs, the human contribution has now reached 30-50 times the average natural level (9.5 Gt C/y versus ca. 0.2-0.3Gt C/y). In the long-term range (1-10x106y), the variable, but much smaller net imbalance between these geological sources und sinks was responsible for the atmospheric CO2-level in the last 400 My (since then comparable temporary reservoirs exist) and influenced via the various feedbacks the climate on earth. In nearly 95% of this long time the climate system was in (nearly) equilibrium conditions and changes occurred extremely slow. Whenever a certain range of higher rate of change of these driving forces were reached, it had - together with other effects - severe influence on the evolution of life, causing 5 large and many minor 'geological accidents'. Based on isotope geochemistry and a fairly good time resolution by orbitally tuned cyclostratigraphy (astrochronology) in the sedimentary record, we are able to quantify these rates of change with reasonable errors. It turns out that the present rate of change - caused by the C-based fossil energy use - is one to two orders of magnitude more rapid than these severe events (impacts excluded) in the earth system. A vast amount of data is available from the ice age cycles. Climate geology (e.g. the group of M. Sarnthein) made considerable progress in understanding the related geological/oceanic processes and proposed a reasonably constrained mass balance of CO2 during the last cycle, which could help us to understand the future

Developing, choosing and using landscape evolution models to inform field-based landscape reconstruction studies

NARCIS (Netherlands)

Temme, A.J.A.M.; Armitage, J.; Attal, M.; Gorp, van Wouter; Coulthard, T.J.; Schoorl, J.M.

2017-01-01

Landscape evolution models (LEMs) are an increasingly popular resource for geomorphologists as they can operate as virtual laboratories where the implications of hypotheses about processes over human to geological timescales can be visualized at spatial scales from catchments to mountain ranges.

Chemistry and evolution of Titan's atmosphere

International Nuclear Information System (INIS)

Strobel, D.F.

1982-01-01

The chemistry and evolution of Titan's atmosphere is reviewed in the light of the scientific findings from the Voyager mission. It is argued that the present N 2 atmosphere may be Titan's initial atmosphere rather than photochemically derived from an original NH 3 atmosphere. The escape rate of hydrogen from Titan is controlled by photochemical production from hydrocarbons. CH 4 is irreversibly converted to less hydrogen rich hydrocarbons, which over geologic time accumulate on the surface to a layer thickness of approximately 0.5 km. Magnetospheric electrons interacting with Titan's exosphere may dissociate enough N 2 into hot, escaping N atoms to remove approximately 0.2 of Titan's present atmosphere over geologic time. The energy dissipation of magnetospheric electrons exceeds solar e.u.v. energy deposition in Titan's atmosphere by an order of magnitude and is the principal driver of nitrogen photochemistry. The environmental conditions in Titan's upper atmosphere are favorable to building up complex molecules, particularly in the north polar cap region. (author)

AEGIS geologic simulation model

International Nuclear Information System (INIS)

Foley, M.G.

1982-01-01

The Geologic Simulation Model (GSM) is used by the AEGIS (Assessment of Effectiveness of Geologic Isolation Systems) program at the Pacific Northwest Laboratory to simulate the dynamic geology and hydrology of a geologic nuclear waste repository site over a million-year period following repository closure. The GSM helps to organize geologic/hydrologic data; to focus attention on active natural processes by requiring their simulation; and, through interactive simulation and calibration, to reduce subjective evaluations of the geologic system. During each computer run, the GSM produces a million-year geologic history that is possible for the region and the repository site. In addition, the GSM records in permanent history files everything that occurred during that time span. Statistical analyses of data in the history files of several hundred simulations are used to classify typical evolutionary paths, to establish the probabilities associated with deviations from the typical paths, and to determine which types of perturbations of the geologic/hydrologic system, if any, are most likely to occur. These simulations will be evaluated by geologists familiar with the repository region to determine validity of the results. Perturbed systems that are determined to be the most realistic, within whatever probability limits are established, will be used for the analyses that involve radionuclide transport and dose models. The GSM is designed to be continuously refined and updated. Simulation models are site specific, and, although the submodels may have limited general applicability, the input data equirements necessitate detailed characterization of each site before application

Morphostructual evolution of the relief of the Rychlebské Mountains (SE Sudeten Mts, Czech Republic)

Czech Academy of Sciences Publication Activity Database

Štěpančíková, Petra

2007-01-01

Roč. 7, č. 1 (2007), s. 15-26 ISSN 1335-9541 R&D Projects: GA ČR GA205/06/1828 Institutional research plan: CEZ:AV0Z30460519 Keywords : morphostructural evolution * neotectonics Subject RIV: DB - Geology ; Mineralogy

Formation-evolution model of uranium-productive basin and its recognition criteria

Energy Technology Data Exchange (ETDEWEB)

Zuyi, Chen; Ziying, Li [Beijing Research Inst. of Uranium Geology, Beijing (China); Weixun, Zhou; Taiyang, Guan [East China Inst. of Technology, Fuzhou (China)

2004-11-15

Based on geologic-tectonic setting and dynamic evolution of important U-productive basins both at home and abroad, authors distinguish six type of U-productive basins, and nominate each type by typical representative of this type, namely Chu-Sarysu and Syr-Darya type, Central Kyzylkum type, Zaural and West-Siberia type, Zabaikal type, Bohemia type, and South Texas type. The formation-evolution model of each type of U-productive basin has been established and recognition criteria have been proposed. Finially, the difference between each type U-productive basin is discussed and some assumption on prospecting for U-productive basins is proposed. (authors)

Formation-evolution model of uranium-productive basin and its recognition criteria

International Nuclear Information System (INIS)

Chen Zuyi; Li Ziying; Zhou Weixun; Guan Taiyang

2004-11-01

Based on geologic-tectonic setting and dynamic evolution of important U-productive basins both at home and abroad, authors distinguish six type of U-productive basins, and nominate each type by typical representative of this type, namely Chu-Sarysu and Syr-Darya type, Central Kyzylkum type, Zaural and West-Siberia type, Zabaikal type, Bohemia type, and South Texas type. The formation-evolution model of each type of U-productive basin has been established and recognition criteria have been proposed. Finially, the difference between each type U-productive basin is discussed and some assumption on prospecting for U-productive basins is proposed. (authors)

Global Journal of Geological Sciences: Editorial Policies

African Journals Online (AJOL)

Focus and Scope. Global Journal of Geological Sciences is aimed at promoting research in all areas of geological Sciences including Petrology, Mineralogy, geophysics, hydrogeology, Engineering geology, Petroleum geology, Palaeontology, environmental geology, Economic geology, etc.

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.

Late quaternary geology in Desaguadero river basin, San Luis, Argentina

International Nuclear Information System (INIS)

Chiesa, J.; Strasser, E.; Gomez, D.; De Miguel, T.

2007-01-01

Absolute radiocarbon datings of the sedimentary successions have come to knowledge enabling us to distinguish the Pleistocene deposits from the supra-lying Holocene ones. A palaeo-environmental evolution is proposed considering climatic fluctuations at the time, their relation with the river unloadings of the Andean glaciers and that proposed for the palaeo-lake of Salina del Bebedero. Sediments are described on the basis of a detailed field sampling, textural analysis (sieved and Bouyoucos) and laboratory geo-chemicals. Their interpretation of the geologic evolution is considered to be very important since it is the only river course on this arid-semi-arid region linked to the reduction of glaciers in the Andes. The sedimentary succession is dominated by high percentages of laminated limes and with green-yellowish to greyish-brown-reddish tones deposited in watery environments of low energy such as lacustrine basins and extended plains of flood, which is why the evolution of the deposit is characterized by the contrast of the values of insolubles (clastic sediment and carbonate) versus solubles (insoluble saline). The climatic cycles dominant and proposed for the center-east Argentine region are identified considering the influence of Andean glaciers on the river systems and the water balances in plain semi-arid environments. (author)

Geologic evolution of the Paraiba do Sul complex, in the central part of the Ribeira belt, based on the geochemistry and U-Pb geochronology studies; Evolucao geologica do complexo Paraiba do Sul, no segmento central da faixa Ribeira, com base em estudos de geoquimica e geocronologia U-Pb

Energy Technology Data Exchange (ETDEWEB)

Valladares, Claudia Sayao

1996-12-31

Aiming the definition of the Complexo Paraiba do Sul evolution, the work presents a geochronological approach by the U-Pb method, considered appropriate to study polideformed terrains. The minerals used to the U-Pb dating (zircon, titanite and monazite) provides information about the ages of rock generation and the successive geological events the rocks were submitted. The U-Pb geochronological approach is pioneer in the investigated area and two questions referent to the Complexo Paraiba do Sul evolution in the central part of the Ribeira belt, were the aim of this approach. The first of them refers to the crystallization epoch and the gneisses metamorphism, interpreted here like orthogneisses, called Unidade Quirino of the Complexo Paraiba do Sul. The second refers to the metamorphism ages and meta sedimentary unit deformation. Looking for the contribution to the Complexo Paraiba do Sul evolution understanding, this work presents the data based on the geologic map of this area, comprising part of the Folha Volta Redonda (1:50.000), including petrographic, structural and microtectonic studies. It also presents and discusses the results of: 17 U-Pb analysis in zircon and titanite of the Complexo Paraiba do Sul orthogneisses collection; 24 geochemical analysis of major, minor, trace elements and ETR of the same collection; an U-Pb analysis in titanite of the Unidade Sao Joao, 5 U-Pb analysis in titanites and/or monazites of granites and granitoids; 12 geochemical analysis including major, minor and trace elements and ETR, in granites and sills of leucogranites. Finally, the data achieved were integrated with the objective to elaborate an evolutive view of the Complexo Paraiba do Sul 157 refs., 54 figs., 17 tabs.

Geologic evolution of the Paraiba do Sul complex, in the central part of the Ribeira belt, based on the geochemistry and U-Pb geochronology studies; Evolucao geologica do complexo Paraiba do Sul, no segmento central da faixa Ribeira, com base em estudos de geoquimica e geocronologia U-Pb

Energy Technology Data Exchange (ETDEWEB)

Valladares, Claudia Sayao

1997-12-31

Aiming the definition of the Complexo Paraiba do Sul evolution, the work presents a geochronological approach by the U-Pb method, considered appropriate to study polideformed terrains. The minerals used to the U-Pb dating (zircon, titanite and monazite) provides information about the ages of rock generation and the successive geological events the rocks were submitted. The U-Pb geochronological approach is pioneer in the investigated area and two questions referent to the Complexo Paraiba do Sul evolution in the central part of the Ribeira belt, were the aim of this approach. The first of them refers to the crystallization epoch and the gneisses metamorphism, interpreted here like orthogneisses, called Unidade Quirino of the Complexo Paraiba do Sul. The second refers to the metamorphism ages and meta sedimentary unit deformation. Looking for the contribution to the Complexo Paraiba do Sul evolution understanding, this work presents the data based on the geologic map of this area, comprising part of the Folha Volta Redonda (1:50.000), including petrographic, structural and microtectonic studies. It also presents and discusses the results of: 17 U-Pb analysis in zircon and titanite of the Complexo Paraiba do Sul orthogneisses collection; 24 geochemical analysis of major, minor, trace elements and ETR of the same collection; an U-Pb analysis in titanite of the Unidade Sao Joao, 5 U-Pb analysis in titanites and/or monazites of granites and granitoids; 12 geochemical analysis including major, minor and trace elements and ETR, in granites and sills of leucogranites. Finally, the data achieved were integrated with the objective to elaborate an evolutive view of the Complexo Paraiba do Sul 157 refs., 54 figs., 17 tabs.

A study on the regional geological setting of uranium metallogenesis in Lu-Zong region

International Nuclear Information System (INIS)

Chen Yifeng; Ma Changming; Fan Huanxin

1996-01-01

This paper presents a new understanding of features of main ore-bearing horizons and magmatic rocks, evolution regularities, regional tectonic characteristics and the compositions and formation of the Yangtze tectonic belt in Lu-Zong region. Favourable horizons, magmatic series of Yangtze-type crust-mantle mixed melting magmatic rocks, activities of regional gigantic deep-seated faults and their subsidiary structures provided good regional geological setting for the formation of uranium and polymetallic mineral resources in this region

Approaches for treating uncertainty in the long term performance assessment of a geological waste repository in clay

International Nuclear Information System (INIS)

Marivoet, J.; Volckaert, G.; Wemaere, I.; Mallants, D.

1998-01-01

In Belgium the current strategy for high-level waste disposal is the geological disposal in a plastic clay layer. The performance assessment approach consists of a systematic scenario selection based on the FEP (features, events and processes) methodology followed by consequence analyses for the selected scenarios. In these consequence analyses the different sources of uncertainty are systematically considered. For the normal evolution scenario, i.e. the scenario which includes all FEP's which are about certain to occur, a stochastic technique of the Monte Carlo type is applied for treating uncertainty. For the altered evolution scenarios a deterministic approach is generally used to evaluate the uncertainties on the long-term. In the case of altered evolution scenarios, comparisons of fluxes from the far field into the biosphere with those calculated for the normal evolution scenario are used, beside dose calculations, to evaluate the safety consequences. Some typical examples of the above approaches will be presented. (author)

Assessment of effectiveness of geologic isolation systems: the AEGIS geologic simulation model

International Nuclear Information System (INIS)

Foley, M.G.; Petrie, G.M.

1981-02-01

Assessment of the post-closure performance of a nuclear waste repository has two basic components: the identification and analysis of potentially disruptive sequences and the pattern of geologic events and processes causing each sequence, and the identification and analysis of the environmental consequences of radionuclide transport and interactions subsequent to disruption of a repository. The AEGIS Scenario Analysis Task is charged with identifying and analyzing potenially disruptive sequences of geologic events and processes. The Geologic Simulation Model (GSM) was developed to evaluate the geologic/hydrologic system surrounding an underground repository, and describe the phenomena that alone, or in concert, could perturb the system and possibly cause a loss of repository integrity. The AEGIS approach is described in this report. It uses an integrated series of models for repository performance analysis; the GSM for a low-resolution, long-term, comprehensive evaluation of the geologic/hydrologic system, followed by more detailed hydrogeologic, radionuclide transport, and dose models to more accurately assess the consequences of disruptive sequences selected from the GSM analyses. This approach is felt to be more cost-effective than an integrated one because the GSM can be used to estimate the likelihoods of different potentially disruptive future evolutionary developments within the geologic/hydrologic system. The more costly consequence models can then be focused on a few disruptive sequences chosen for their representativeness and effective probabilities

Geological studies in Alaska by the U.S. Geological Survey, 1999

Science.gov (United States)

Gough, Larry P.; Wilson, Frederic H.

2001-01-01

The collection of nine papers that follow continue the series of U.S. Geological Survey (USGS) investigative reports in Alaska under the broad umbrella of the geologic sciences. The series presents new and sometimes preliminary findings that are of interest to earth scientists in academia, government, and industry; to land and resource managers; and to the general public. Reports presented in Geologic Studies in Alaska cover a broad spectrum of topics from various parts of the State (fig. 1), serving to emphasize the diversity of USGS efforts to meet the Nation's needs for earth-science information in Alaska.

Scenarios used for the evaluations of the safety of a site for adioactive waste disposal in deep geologic formations

International Nuclear Information System (INIS)

Escalier des Orres, P.; Devillers, C.; Cernes, A.

1989-11-01

The selection and qualification procedure of a site for radioactive wastes disposal in a deep geologic formation, has begun in France in the early eighties. The public authorities, on ANDRA's proposal, has preselected in 1987 four sites, each of them coppresponding to a type, of geologic formations (granite, clay, salt and shale). Within two years, one of these sites will be chosen for the location of an undergound laboratory. The safety analysis for the site's qualification uses evolution scenarios of the repository and its environment, chosen according to a deterministic method. With an appropriate detail level, are defined a reference scenario and scenario with random events [fr

On the evolution of the Kazaure Schist Belt of NW Nigeria: a re ...

African Journals Online (AJOL)

Global Journal of Geological Sciences ... Abstract. All previous models of evolution of the Kazaure Schist Belt (KZSB) invoked a simple ensialic mechanism in the context of Pan-African deformation which led to the formation of a marginal back-arc basin floored by continental materials that accepted sediments. The closure ...

Modelling the long-term evolution of geological radwaste disposal facilities

International Nuclear Information System (INIS)

Dames and Moore International Twickenham

1990-01-01

The report aims to answer questions such as How much do we know about environmental change, How does it apply to the performance assessment of radioactive waste disposal sites and What methods are available for incorporating considerations of environmental change into performance assessment. The document comprises two parts: Part 1 presents a review of the status of research into the effects of long-term environmental changes on deep land disposal facilities for radioactive waste, and then outlines a general specification for modelling these efforts; Part 2 presents background research on permafrost evolution and its potential effects on groundwater systems. Although much work exists on the growth of ice in soils, at shallow levels, relatively little is known about the growth of deep permafrost. A large appendix is devoted to the theoretical work on permafrost growth and its conclusions

77 FR 19032 - Geological Survey

Science.gov (United States)

2012-03-29

... DEPARTMENT OF THE INTERIOR Geological Survey Announcement of National Geospatial Advisory Committee Meeting AGENCY: U.S. Geological Survey, Interior. ACTION: Notice of meeting. SUMMARY: The National.... Geological Survey (703-648-6283, [email protected] ). Registrations are due by April 13, 2012. While the...

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

Evolution caused by extreme events.

Science.gov (United States)

Grant, Peter R; Grant, B Rosemary; Huey, Raymond B; Johnson, Marc T J; Knoll, Andrew H; Schmitt, Johanna

2017-06-19

Extreme events can be a major driver of evolutionary change over geological and contemporary timescales. Outstanding examples are evolutionary diversification following mass extinctions caused by extreme volcanism or asteroid impact. The evolution of organisms in contemporary time is typically viewed as a gradual and incremental process that results from genetic change, environmental perturbation or both. However, contemporary environments occasionally experience strong perturbations such as heat waves, floods, hurricanes, droughts and pest outbreaks. These extreme events set up strong selection pressures on organisms, and are small-scale analogues of the dramatic changes documented in the fossil record. Because extreme events are rare, almost by definition, they are difficult to study. So far most attention has been given to their ecological rather than to their evolutionary consequences. We review several case studies of contemporary evolution in response to two types of extreme environmental perturbations, episodic (pulse) or prolonged (press). Evolution is most likely to occur when extreme events alter community composition. We encourage investigators to be prepared for evolutionary change in response to rare events during long-term field studies.This article is part of the themed issue 'Behavioural, ecological and evolutionary responses to extreme climatic events'. © 2017 The Author(s).

A SKOS-based multilingual thesaurus of geological time scale for interopability of online geological maps

NARCIS (Netherlands)

Ma, X.; Carranza, E.J.M.; Wu, C.; Meer, F.D. van der; Liu, G.

2011-01-01

The usefulness of online geological maps is hindered by linguistic barriers. Multilingual geoscience thesauri alleviate linguistic barriers of geological maps. However, the benefits of multilingual geoscience thesauri for online geological maps are less studied. In this regard, we developed a

Database system of geological information for geological evaluation base of NPP sites(I)

International Nuclear Information System (INIS)

Lim, C. B.; Choi, K. R.; Sim, T. M.; No, M. H.; Lee, H. W.; Kim, T. K.; Lim, Y. S.; Hwang, S. K.

2002-01-01

This study aims to provide database system for site suitability analyses of geological information and a processing program for domestic NPP site evaluation. This database system program includes MapObject provided by ESRI and Spread 3.5 OCX, and is coded with Visual Basic language. Major functions of the systematic database program includes vector and raster farmat topographic maps, database design and application, geological symbol plot, the database search for the plotted geological symbol, and so on. The program can also be applied in analyzing not only for lineament trends but also for statistic treatment from geologically site and laboratory information and sources in digital form and algorithm, which is usually used internationally

An appraisal of the Permian palaeobiodiversity and geology of the Ib-River Basin, eastern coastal area, India

Science.gov (United States)

Goswami, Shreerup; Saxena, Anju; Singh, Kamal Jeet; Chandra, Shaila; Cleal, Christopher J.

2018-05-01

The Ib-River Basin situated in the east coastal area of India, in Odisha State is a south-eastern part of the Mahanadi Master Basin. A large number of plant macrofossils belonging to the Glossopteris flora were described and documented between 2006 and 2010 from various localities of the Barakar and Lower Kamthi formations of this basin. The floral components representing leaves, roots and fructifications in these assemblages belong to the Lycopodiales, Equisetales, Sphenophyllales, Filicales, Cordaitales, Cycadales, Ginkgoales, Coniferales and Glossopteridales. In the present study, all the available data pertaining to the biological remains, petrological analyses as well as the geology of this basin are reviewed and analyzed to deduce and reconstruct the biostratigraphy, palaeoclimate, palaeoenvironment and the landscape of this basin during Permian time in general and during the deposition of Barakar (Artinskian - Kungurian) and Lower Kamthi (Lopingian) formations in particular. The floral composition suggests the prevalence of a temperate climate with a slight change from warm moist to warm dry conditions during the deposition of the Barakar Formation and warm and humid during the deposition of Lower Kamthi sediments. Distribution of various plant groups in the Barakar and Lower Kamthi formations have been shown to depict the biodiversity trends. Vegetational reconstructions during the deposition of the Barakar and Lower Kamthi formations around the Ib-River Basin have also been attempted based on all the fossil records from this area. The status of unclassified Barakar and Kamthi formations has been redefined. Apart from megafloristics, the palynology of the basin is also discussed. Possible marine incursions and marine marginal environment in the Ib-Basin during Permian are overtly summarized on the basis of records of acritarchs, typical marine ichnofossils and evidences of wave activity in Lower Gondwana sediments of this Basin.

OneGeology Web Services and Portal as a global geological SDI - latest standards and technology

Science.gov (United States)

Duffy, Tim; Tellez-Arenas, Agnes

2014-05-01

The global coverage of OneGeology Web Services (www.onegeology.org and portal.onegeology.org) achieved since 2007 from the 120 participating geological surveys will be reviewed and issues arising discussed. Recent enhancements to the OneGeology Web Services capabilities will be covered including new up to 5 star service accreditation scheme utilising the ISO/OGC Web Mapping Service standard version 1.3, core ISO 19115 metadata additions and Version 2.0 Web Feature Services (WFS) serving the new IUGS-CGI GeoSciML V3.2 geological web data exchange language standard (http://www.geosciml.org/) with its associated 30+ IUGS-CGI available vocabularies (http://resource.geosciml.org/ and http://srvgeosciml.brgm.fr/eXist2010/brgm/client.html). Use of the CGI simpelithology and timescale dictionaries now allow those who wish to do so to offer data harmonisation to query their GeoSciML 3.2 based Web Feature Services and their GeoSciML_Portrayal V2.0.1 (http://www.geosciml.org/) Web Map Services in the OneGeology portal (http://portal.onegeology.org). Contributing to OneGeology involves offering to serve ideally 1:1000,000 scale geological data (in practice any scale now is warmly welcomed) as an OGC (Open Geospatial Consortium) standard based WMS (Web Mapping Service) service from an available WWW server. This may either be hosted within the Geological Survey or a neighbouring, regional or elsewhere institution that offers to serve that data for them i.e. offers to help technically by providing the web serving IT infrastructure as a 'buddy'. OneGeology is a standards focussed Spatial Data Infrastructure (SDI) and works to ensure that these standards work together and it is now possible for European Geological Surveys to register their INSPIRE web services within the OneGeology SDI (e.g. see http://www.geosciml.org/geosciml/3.2/documentation/cookbook/INSPIRE_GeoSciML_Cookbook%20_1.0.pdf). The Onegeology portal (http://portal.onegeology.org) is the first port of call for anyone

Operation environment construction of geological information database for high level radioactive waste geological disposal

International Nuclear Information System (INIS)

Wang Peng; Gao Min; Huang Shutao; Wang Shuhong; Zhao Yongan

2014-01-01

To fulfill the requirements of data storage and management in HLW geological disposal, a targeted construction method for data operation environment was proposed in this paper. The geological information database operation environment constructed by this method has its unique features. And it also will be the important support for HLW geological disposal project and management. (authors)

Analysis of geological condition and prospecting potential of uranium metallogenesis in Maling granite mass

International Nuclear Information System (INIS)

Shao Fei; Zou Maoqing; Wu Yong; Xu Jinshan; Xu Wang; Chen Chang

2011-01-01

Based on the study of regional geological evolution of Maling granite mass, uranium content of granite mass and its peripheric strata, petrogeochemistry and the known spatial distribution pattern of uranium mineralization and ore-controlling structures, new recognition is 1) Maling composite mass is the 'S' type re-melted granite, 2) the accumulative area of regional uranium metallogenic substances forms uranium-rich re-melted strata, 3) magma evolution is the matter base for the uranium-rich hydrotherm, 4) NE-trending main faults are channels for metallogenesis and the lateral high-angle dipping faults, fractures and interlayer fractures in the peripheric strata are the spaces of mineralization. The ore intersected by drilling in Maling granite is acidic type. Prospecting potential of Maling granite mass is analyzed, and preferable prospecting space is delineated for further exploration. (authors)

Commentary on the evolution of the exploration and evaluation process

International Nuclear Information System (INIS)

Tivy, S.V.; Mercier, J.M.

1991-01-01

Technical personnel in the coal industry have witnessed a significant restructuring and refocusing of individual and corporate activities in recent years. This new focus has been brought about by fluctuating economic and political conditions. In particular, activities associated with coal exploration, management, and reserve definition have been profoundly affected. Whereas the positive and growing coal industry of the late 1970s and the early 1980s spawned innovative and generally well-funded research and operationally supportive programs, the late 1980s have seen the evolution of a strongly pragmatic industrial course and a declining emphasis on geologic research and academic involvement. In spite of the constrained nature of the industry, individuals in the field of coal geology today find the profession in weathering the recession cycle in good shape. Although the ranks of participants have been thinned, the spirit of geologic intuition, adaptability, and creativity is strong and ready to meet the challenges of the future. It is evident that the role of the coal geologist in exploration, reserve analysis, operations support, research, and management is vital and appropriate. This review re-examines industrial cycles, the basic goals of reserve evaluation, and the importance of new tools, attitudes, and management methods in today's practice of coal exploration and geology

Engineering geology and environmental protection

Energy Technology Data Exchange (ETDEWEB)

Sergeev, E M

1979-01-01

A classification is made of the anthropogenic processes in the environment into global, local, universally distributed, zonal, regional, and essentially local processes. Engineering geology is defined as the principal science concerned with the study of the geological medium which in turn involves the study of fossil fuel geology. 22 references.

Methodology of safety assessment and sensitivity analysis for geologic disposal of high-level radioactive waste

International Nuclear Information System (INIS)

Kimura, Hideo; Takahashi, Tomoyuki; Shima, Shigeki; Matsuzuru, Hideo

1995-01-01

A deterministic safety assessment methodology has been developed to evaluate long-term radiological consequences associated with geologic disposal of high-level radioactive waste, and to demonstrate a generic feasibility of geologic disposal. An exposure scenario considered here is based on a normal evolution scenario which excludes events attributable to probabilistic alterations in the environment. A computer code system GSRW thus developed is based on a non site-specific model, and consists of a set of sub-modules for calculating the release of radionuclides from engineered barriers, the transport of radionuclides in and through the geosphere, the behavior of radionuclides in the biosphere, and radiation exposures of the public. In order to identify the important parameters of the assessment models, an automated procedure for sensitivity analysis based on the Differential Algebra method has been developed to apply to the GSRW. (author)

New safety concept for geological disposal in Japan - -16339

International Nuclear Information System (INIS)

Kitayama, Kazumi

2009-01-01

This paper describes a new safety concept for the Japanese geological disposal program, which is a development of the conventional multi-barrier system concept. The Japanese government established the 'Nuclear Waste Management Organization of Japan' (NUMO) as an implementation body in 2000 based on the 'Final disposal act' following the publication of the 'H-12 Report', which confirmed the scientific and engineering feasibility of HLW geological disposal in Japan. Since then, NUMO has undertaken further technical developments aimed at achieving safe and efficient implementation of final disposal. The safety concept developed in the 'H-12 Report' provides sufficient safety on the basis of site-generic considerations. However, it is considered to be over-conservative and therefore does not represent the most probable performance of the engineered or natural barriers. Recently, concrete measures have been proposed requiring the safety case to be presented in terms of a realistic assessment of the most probable performance. This approach takes into account the safety functions of both engineered and natural barriers as well as the long-term static geochemical equilibrium. In particular, the evolution of the safety performance of engineered and natural barriers can be efficiently augmented by the realistic long-term geochemical equilibrium. (author)

Geologic characterization of Cuvette Centrale petroleum systems Congo-DRC

Energy Technology Data Exchange (ETDEWEB)

Vicentelli, Maria Gabriela C.; Barbosa, Mauro; Rezende, Nelio G.A.M. [HRT Petroleum, Rio de Janeiro, RJ (Brazil)

2008-07-01

The Cuvette Centrale is an almost unexplored basin, which contains some petroleum system elements that indicate the presence of hydrocarbons. In this sense; this paper presents an exploratory alternative for this intracratonic basin. The interpretation of the limited gravimetric, magnetometric, geochemical and seismic available data allowed the identification of many huge structural features and also some areas with hydrocarbon potential for stratigraphic traps. The presence of several oil and gas seeps widespread around the Busira and Lokoro sub-basins indicate that at least one active petroleum system exist in the basin. Despite only four wells have been drilled in the basin, one of them presented oil shows during drilling. Geological correlations between Brazilian Paleozoic basins and Cuvette Centrale sedimentary sequences permitted to conclude that Cambro-Ordovician and Siluro-Devonian source rocks must be present and active in the Cuvette Centrale basin. The tectono-stratigraphic evolution history of the Cuvette Centrale from Neo proterozoic to Recent times shows extensional and compressional/transpressional alternating phases along the geological time. The most confident petroleum system expected in the Cuvette Centrale is characterized by the Cambrian Mamungi shale - source rock - and the Cambro-Ordovician. Upper Arenaceous Sequence - reservoirs, as observed in the MBandaka and Gilson wells and confirmed by surface geology in outcrops. Besides, other potential petroleum systems are expected to occur in the basin. One is characterized by the Neo proterozoic Itury Group source rock and reservoirs in the mature/over mature stage, the others are the Siluro-Devonian and Cretaceous source rocks and reservoirs, expected to occur with better maturity conditions only in the deeper parts of the basin. (author)

Technical know-how for the investigation and modelling of topographic evolution for site characterisation - 59171

International Nuclear Information System (INIS)

Doke, Ryosuke; Yasue, Ken-ichi; Niizato, Tadafumi; Nakayasu, Akio

2012-01-01

Geological hazard assessments are being used to make important decisions relevant to nuclear facilities such as a repository for deep geological disposal of high-level radioactive waste. With respect to such repositories, topographic evolution is a key issue for description of the long-term evolution of a groundwater flow characteristics in time spans of tens to hundreds of thousands of years. The construction of topographic evolution models is complex, involving tacit knowledge and working processes. Therefore, it is important to externalise, that is to explicitly present the tacit knowledge and decision-making processes used by experts in the model building unambiguously, with thorough documentation and to provide key knowledge to support planning and implementation of investigations. In this study, documentation of the technical know-how used for the construction of a topographic evolution model is demonstrated. The process followed in the construction of the model is illustrated using task-flow logic diagrams; the process involves four main tasks with several sub-tasks. The task-flow followed for an investigation to estimate uplift rates linked to the task-flow for the modelling of topographic evolution is also illustrated. In addition, the decision-making processes in the investigation are expressed in logical IF-THEN format for each task. Based on the documented technical know-how, an IT-based Expert System was constructed. In future work, it is necessary to analyse the knowledge, including the management of uncertainties in the modelling and investigations, and to integrate fundamental ideas for managing uncertainties with expert system. (authors)

Geology Field Trips as Performance Evaluations

Science.gov (United States)

Bentley, Callan

2009-01-01

One of the most important goals the author has for students in his introductory-level physical geology course is to give them the conceptual skills for solving geologic problems on their own. He wants students to leave his course as individuals who can use their knowledge of geologic processes and logic to figure out the extended geologic history…

Effects of climatic and geological processes during the pleistocene on the evolutionary history of the northern cavefish, Amblyopsis spelaea (teleostei: amblyopsidae).

Science.gov (United States)

Niemiller, Matthew L; McCandless, James R; Reynolds, R Graham; Caddle, James; Near, Thomas J; Tillquist, Christopher R; Pearson, William D; Fitzpatrick, Benjamin M

2013-04-01

Climatic and geological processes associated with glaciation cycles during the Pleistocene have been implicated in influencing patterns of genetic variation and promoting speciation of temperate flora and fauna. However, determining the factors promoting divergence and speciation is often difficult in many groups because of our limited understanding of potential vicariant barriers and connectivity between populations. Pleistocene glacial cycles are thought to have significantly influenced the distribution and diversity of subterranean invertebrates; however, impacts on subterranean aquatic vertebrates are less clear. We employed several hypothesis-driven approaches to assess the impacts of Pleistocene climatic and geological changes on the Northern Cavefish, Amblyopsis spelaea, whose current distribution occurs near the southern extent of glacial advances in North America. Our results show that the modern Ohio River has been a significant barrier to dispersal and is correlated with patterns of genetic divergence. We infer that populations were isolated in two refugia located north and south of the Ohio River during the most recent two glacial cycles with evidence of demographic expansion in the northern isolate. Finally, we conclude that climatic and geological processes have resulted in the formation of cryptic forms and advocate recognition of two distinct phylogenetic lineages currently recognized as A. spelaea. © 2012 The Author(s). Evolution© 2012 The Society for the Study of Evolution.

Mercury's Early Geologic History

Science.gov (United States)

Denevi, B. W.; Ernst, C. M.; Klima, R. L.; Robinson, M. S.

2018-05-01

A combination of geologic mapping, compositional information, and geochemical models are providing a better understanding of Mercury's early geologic history, and allow us to place it in the context of the Moon and the terrestrial planets.

Modeling of thermal evolution of near field area around single pit mode nuclear waste canister disposal in soft rocks

International Nuclear Information System (INIS)

Bajpai, R.K.; Verma, A.K.; Maheshwar, Sachin

2016-01-01

Soft rocks like argillites/shales are under consideration worldwide as host rock for geological disposal of vitrified as well as spent fuel nuclear waste. The near field around disposed waste canister at 400-500m depth witnesses a complex heat field evolution due to varying thermal characteristics of rocks, coupling with hydraulic processes and varying intensity of heat flux from the canister. Smooth heat dissipation across the rock is desirable to avoid buildup of temperature beyond design limit (100 °C) and resultant micro fracturing due to thermal stresses in the rocks and intervening buffer clay layers. This also causes enhancement of hydraulic conductivity of the rocks, radionuclide transport and greater groundwater ingress towards the canister. Hence heat evolution modeling constitutes an important part of safety assessment of geological disposal facilities

In Review (Geology): Alpine Landscape Evolution Dominated by Cirque Retreat

Science.gov (United States)

Oskin, Michael; Burbank, Doug

2005-01-01

Despite the abundance in alpine terrain of glacially dissected landscapes, the magnitude and geometry of glacial erosion can rarely be defined. In the eastern Kyrgyz Range, a widespread unconformity exhumed as a geomorphic surface provides a regional datum with which to calibrate erosion. As tectonically driven surface uplift has progressively pushed this surface into the zone of ice accumulation, glacial erosion has overprinted the landscape. With as little as 500 m of incision into rocks underlying the unconformity, distinctive glacial valleys display their deepest incision adjacent to cirque headwalls. The expansion of north-facing glacial cirques at the expense of south-facing valleys has driven the drainage divide southwards at rates up to 2 to 3 times the rate of valley incision. Existing ice-flux-based glacial erosion rules incompletely model expansion of glacial valleys via cirque retreat into the low-gradient unconformity remnants. Local processes that either directly sap cirque headwalls or inhibit erosion down-glacier appear to control, at least initially, alpine landscape evolution.

Early onset of industrial-era warming across the oceans and continents.

Science.gov (United States)

Abram, Nerilie J; McGregor, Helen V; Tierney, Jessica E; Evans, Michael N; McKay, Nicholas P; Kaufman, Darrell S

2016-08-25

The evolution of industrial-era warming across the continents and oceans provides a context for future climate change and is important for determining climate sensitivity and the processes that control regional warming. Here we use post-ad 1500 palaeoclimate records to show that sustained industrial-era warming of the tropical oceans first developed during the mid-nineteenth century and was nearly synchronous with Northern Hemisphere continental warming. The early onset of sustained, significant warming in palaeoclimate records and model simulations suggests that greenhouse forcing of industrial-era warming commenced as early as the mid-nineteenth century and included an enhanced equatorial ocean response mechanism. The development of Southern Hemisphere warming is delayed in reconstructions, but this apparent delay is not reproduced in climate simulations. Our findings imply that instrumental records are too short to comprehensively assess anthropogenic climate change and that, in some regions, about 180 years of industrial-era warming has already caused surface temperatures to emerge above pre-industrial values, even when taking natural variability into account.

Origin and evolution of the Pirituba aluminous calc-alkalic magma, state of Sao Paulo, SE Brazil

International Nuclear Information System (INIS)

Wernick, Eberhard

1999-01-01

The origin and evolution of the Late Proterozoic calc-alkalic Pirituba magmatism near the city of Sao Paulo, State of Sao Paulo, SE Brazil, are presented and discussed on the basis of geological, petrographic, mineralogical, chemical (rocks and minerals), isotopic and zircon typology data. (author)

The geology of the Vaalputs radioactive waste disposal site, with implications for granite-charnockite relationships and crustal evolution in western Namaqualand

International Nuclear Information System (INIS)

Andreoli, M.A.G.; Brynard, H.J.; Anderson, N.J.B.; Hart, R.J.; Moore, J.M.; Welke, H.

1990-01-01

The Precambrian geology of the Valputs site is characterized by extensive sheets of Spektakel Suite syntectonic granite gneisses. Experimental methods used for the geological evaluation of the Vaalputs site included semi-regional and site-specific mapping. All main rock types were petrologically and geochemically classified. In addition, preliminary Rb-Sr whole-rock ages were calculated for the main lithotypes, together with Sm-Nd dating. The investigations for the licensing of the Vaalputs site have revealed numerous intriguing aspects of the crustal history in southwestern Namaqualand. 10 refs

Assessing the geologic and climatic forcing of biodiversity and evolution surrounding the Gulf of California

Science.gov (United States)

Dolby, Greer; Bennett, Scott E. K.; Lira-Noriega, Andres; Wilder, Benjamin T.; Munguia-Vega, Adrian

2015-01-01

For almost a century the Baja California peninsula (Peninsula), Gulf of California (Gulf), and broader Sonoran Desert region (figure 1) have drawn geologists and biologists alike to study its unique physical and evolutionary processes (e.g., Wittich 1920; Darton 1921; Nelson 1921; Johnston 1924; Beal 1948; Durham and Allison 1960). The challenge remains to untangle the long, intricate, and at times enigmatic geological and climatological histories that have shaped the high levels of endemism and biodiversity observed in the region today (Van Devender 1990; Grismer 2000; Riddle et al. 2000).

Geology of the Southern Utopia Planitia Highland-Lowland Boundary Plain: Second Year Results and Third Year Plan

Science.gov (United States)

Skinner, J. A., Jr.; Tanaka, K. L.; Hare, T. M.

2009-01-01

The southern Utopia highland-lowland boundary (HLB) extends >1500 km westward from Hyblaeus Dorsa to the topographic saddle that separates Isidis and Utopia Planitiae. It contains bench-like platforms that contain depressions, pitted cones (some organized into arcuate chains and thumb-print terrain), isolated domes, buried circular depressions, ring fractures, polygonal fractures, and other locally- to regionally-dispersed landforms [1-2]. The objective of this map project is to clarify the geologic evolution of the southern Utopia Planitia HLB by identifying the geologic, structural, and stratigraphic relationships of surface materials in MTMs 10237, 15237, 20237, 10242, 15242, 20242, 10247, 15247, and 20247. The project was originally awarded in April, 2007 and is in its final year of support. Mapping is on-schedule and formal map submission will occur by December, 2009, with finalization anticipated by April, 2010. Herein, we (1) review specifics regarding mapping data and methods, (2) present nomenclature requests that we feel will assist with unit descriptions, (3) describe Year 2 mapping and science accomplishments, and (4) outline Year 3 technical and managerial approaches for finalizing the geologic map.

Geologic mapping procedure: Final draft

International Nuclear Information System (INIS)

1987-09-01

Geologic mapping will provide a baseline record of the subsurface geology in the shafts and drifts of the Exploratory Shaft Facility (ESF). This information will be essential in confirming the specific repository horizon, selecting representative locations for the in situ tests, providing information for construction and decommissioning seal designs, documenting the excavation effects, and in providing information for performance assessment, which relates to the ultimate suitability of the site as a nuclear waste repository. Geologic mapping will be undertaken on the walls and roof, and locally on the floor within the completed At-Depth Facility (ADF) and on the walls of the two access shafts. Periodic mapping of the exposed face may be conducted during construction of the ADF. The mapping will be oriented toward the collection and presentation of geologic information in an engineering format and the portrayal of detailed stratigraphic information which may be useful in confirmation of drillhole data collected as part of the surface-based testing program. Geologic mapping can be considered as a predictive tool as well as a means of checking design assumptions. This document provides a description of the required procedures for geologic mapping for the ESF. Included in this procedure is information that qualified technical personnel can use to collect the required types of geologic descriptions, at the appropriate level of detail. 5 refs., 3 figs., 1 tab

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

Environmental safety case and cement-related issues for intermediate-level waste in a co-located geological disposal facility

International Nuclear Information System (INIS)

Norris, Simon; Williams, Steve

2012-01-01

Simon Norris of the NDA described safety case and cement-related issues for a geological disposal facility for ILW. The Environmental Safety Case (ESC) needs to demonstrate a clear understanding of: - The disposal facility in its geological setting. - How the disposal system will evolve. - How the various components of system (including cementitious materials) contribute to meeting the requirement of providing a safe long-term solution for the disposed wastes. The ESC must include and support the key environmental safety arguments with underpinning lines of reasoning and detailed analysis, assessments and supporting evidence (including those relating to cementitious materials). In an ILW disposal system, cementitious materials could be used in several ways: - As in-package grouting materials and package materials. - Backfill material. - Shotcrete and other vault lining technologies that could be employed during construction and operation. - Engineered seals. - Structural materials. Given that cementitious materials will play important roles in the disposal system - and within a general strategy for managing uncertainty - the NDA is conducting, or has recently conducted, research into the following topics: - Assessment of the potential for interactions between disposal modules for low- and intermediate-level wastes and for HLW and spent fuel. - The effect of possible cementitious vault liners (e.g. composed from shotcrete) on the early post-closure evolution of waste-derived gas in a geological disposal facility for low- and intermediate-level wastes. - The evolution of cementitious backfill materials, including cracking, and related evolution of groundwater flow and chemistry in the vault environment of a geological disposal facility. - Evidence from nature and archaeology relevant to the long-term properties of cement. - Interaction of waste-derived gas (particularly carbon-14 bearing gas) with cementitious materials in the facility near-field. - The choice of in

The Carboniferous to Jurassic evolution of the pre-Alpine basement of Crete: Constraints from U-Pb and U-(Th)-Pb dating of orthogneiss, fission-track dating of zircon, structural and petrological data

Czech Academy of Sciences Publication Activity Database

Romano, S. S.; Brix, M. R.; Dörr, K.; Fiala, Jiří; Krenn, E.; Zulauf, G.

2006-01-01

Roč. 260, - (2006), s. 69-90 ISSN 0375-6440 Institutional research plan: CEZ:AV0Z30130516 Keywords : tectonic-evolution * Carboniferous * Jurassic * uranium-lead-dating * orthogneiss * fission-track-dating * zircon * structural-geology * petrology * metamorphism * high-temperature Subject RIV: DB - Geology ; Mineralogy

Geology

Data.gov (United States)

Kansas Data Access and Support Center — This database is an Arc/Info implementation of the 1:500,000 scale Geology Map of Kansas, M­23, 1991. This work wasperformed by the Automated Cartography section of...

Symbiosis in cell evolution: Life and its environment on the early earth

Science.gov (United States)

Margulis, L.

1981-01-01

The book treats cell evolution from the viewpoint of the serial endosymbiosis theory of the origin of organelles. Following a brief outline of the symbiotic theory, which holds that eukaryotes evolved by the association of free-living bacteria with a host prokaryote, the diversity of life is considered, and five kingdoms of organisms are distinguished: the prokaryotic Monera and the eukaryotic Protoctista, Animalia, Fungi and Plantae. Symbiotic and traditional direct filiation theories of cell evolution are compared. Recent observations of cell structure and biochemistry are reviewed in relation to early cell evolution, with attention given to the geological context for the origin of eukaryotic cells, the origin of major bacterial anaerobic pathways, the relationship between aerobic metabolism and atmospheric oxygen, criteria for distinguishing symbiotic organelles from those that originated by differentiation, and the major classes of eukaryotic organelles: mitochondria, cilia, microtubules, the mitotic and meiotic apparatuses, and pastids. Cell evolution during the Phanerozoic is also discussed with emphasis on the effects of life on the biosphere

Disribution and interplay of geologic processes on Titan from Cassini radar data

Science.gov (United States)

Lopes, R.M.C.; Stofan, E.R.; Peckyno, R.; Radebaugh, J.; Mitchell, K.L.; Mitri, Giuseppe; Wood, C.A.; Kirk, R.L.; Wall, S.D.; Lunine, J.I.; Hayes, A.; Lorenz, R.; Farr, Tom; Wye, L.; Craig, J.; Ollerenshaw, R.J.; Janssen, M.; LeGall, A.; Paganelli, F.; West, R.; Stiles, B.; Callahan, P.; Anderson, Y.; Valora, P.; Soderblom, L.

2010-01-01

The Cassini Titan Radar Mapper is providing an unprecedented view of Titan's surface geology. Here we use Synthetic Aperture Radar (SAR) image swaths (Ta-T30) obtained from October 2004 to December 2007 to infer the geologic processes that have shaped Titan's surface. These SAR swaths cover about 20% of the surface, at a spatial resolution ranging from ~350 m to ~2 km. The SAR data are distributed over a wide latitudinal and longitudinal range, enabling some conclusions to be drawn about the global distribution of processes. They reveal a geologically complex surface that has been modified by all the major geologic processes seen on Earth - volcanism, tectonism, impact cratering, and erosion and deposition by fluvial and aeolian activity. In this paper, we map geomorphological units from SAR data and analyze their areal distribution and relative ages of modification in order to infer the geologic evolution of Titan's surface. We find that dunes and hummocky and mountainous terrains are more widespread than lakes, putative cryovolcanic features, mottled plains, and craters and crateriform structures that may be due to impact. Undifferentiated plains are the largest areal unit; their origin is uncertain. In terms of latitudinal distribution, dunes and hummocky and mountainous terrains are located mostly at low latitudes (less than 30 degrees), with no dunes being present above 60 degrees. Channels formed by fluvial activity are present at all latitudes, but lakes are at high latitudes only. Crateriform structures that may have been formed by impact appear to be uniformly distributed with latitude, but the well-preserved impact craters are all located at low latitudes, possibly indicating that more resurfacing has occurred at higher latitudes. Cryovolcanic features are not ubiquitous, and are mostly located between 30 degrees and 60 degrees north. We examine temporal relationships between units wherever possible, and conclude that aeolian and fluvial

Distribution and interplay of geologic processes on Titan from Cassini radar data

Science.gov (United States)

Lopes, R.M.C.; Stofan, E.R.; Peckyno, R.; Radebaugh, J.; Mitchell, K.L.; Mitri, Giuseppe; Wood, C.A.; Kirk, R.L.; Wall, S.D.; Lunine, J.I.; Hayes, A.; Lorenz, R.; Farr, Tom; Wye, L.; Craig, J.; Ollerenshaw, R.J.; Janssen, M.; LeGall, A.; Paganelli, F.; West, R.; Stiles, B.; Callahan, P.; Anderson, Y.; Valora, P.; Soderblom, L.

2010-01-01

The Cassini Titan Radar Mapper is providing an unprecedented view of Titan's surface geology. Here we use Synthetic Aperture Radar (SAR) image swaths (Ta-T30) obtained from October 2004 to December 2007 to infer the geologic processes that have shaped Titan's surface. These SAR swaths cover about 20% of the surface, at a spatial resolution ranging from ???350 m to ???2 km. The SAR data are distributed over a wide latitudinal and longitudinal range, enabling some conclusions to be drawn about the global distribution of processes. They reveal a geologically complex surface that has been modified by all the major geologic processes seen on Earth - volcanism, tectonism, impact cratering, and erosion and deposition by fluvial and aeolian activity. In this paper, we map geomorphological units from SAR data and analyze their areal distribution and relative ages of modification in order to infer the geologic evolution of Titan's surface. We find that dunes and hummocky and mountainous terrains are more widespread than lakes, putative cryovolcanic features, mottled plains, and craters and crateriform structures that may be due to impact. Undifferentiated plains are the largest areal unit; their origin is uncertain. In terms of latitudinal distribution, dunes and hummocky and mountainous terrains are located mostly at low latitudes (less than 30??), with no dunes being present above 60??. Channels formed by fluvial activity are present at all latitudes, but lakes are at high latitudes only. Crateriform structures that may have been formed by impact appear to be uniformly distributed with latitude, but the well-preserved impact craters are all located at low latitudes, possibly indicating that more resurfacing has occurred at higher latitudes. Cryovolcanic features are not ubiquitous, and are mostly located between 30?? and 60?? north. We examine temporal relationships between units wherever possible, and conclude that aeolian and fluvial/pluvial/lacustrine processes are the

Mantle flow influence on subduction evolution

Science.gov (United States)

Chertova, Maria V.; Spakman, Wim; Steinberger, Bernhard

2018-05-01

The impact of remotely forced mantle flow on regional subduction evolution is largely unexplored. Here we investigate this by means of 3D thermo-mechanical numerical modeling using a regional modeling domain. We start with simplified models consisting of a 600 km (or 1400 km) wide subducting plate surrounded by other plates. Mantle inflow of ∼3 cm/yr is prescribed during 25 Myr of slab evolution on a subset of the domain boundaries while the other side boundaries are open. Our experiments show that the influence of imposed mantle flow on subduction evolution is the least for trench-perpendicular mantle inflow from either the back or front of the slab leading to 10-50 km changes in slab morphology and trench position while no strong slab dip changes were observed, as compared to a reference model with no imposed mantle inflow. In experiments with trench-oblique mantle inflow we notice larger effects of slab bending and slab translation of the order of 100-200 km. Lastly, we investigate how subduction in the western Mediterranean region is influenced by remotely excited mantle flow that is computed by back-advection of a temperature and density model scaled from a global seismic tomography model. After 35 Myr of subduction evolution we find 10-50 km changes in slab position and slab morphology and a slight change in overall slab tilt. Our study shows that remotely forced mantle flow leads to secondary effects on slab evolution as compared to slab buoyancy and plate motion. Still these secondary effects occur on scales, 10-50 km, typical for the large-scale deformation of the overlying crust and thus may still be of large importance for understanding geological evolution.

Practical aspects of geological prediction

International Nuclear Information System (INIS)

Mallio, W.J.; Peck, J.H.

1981-01-01

Nuclear waste disposal requires that geology be a predictive science. The prediction of future events rests on (1) recognizing the periodicity of geologic events; (2) defining a critical dimension of effect, such as the area of a drainage basin, the length of a fault trace, etc; and (3) using our understanding of active processes the project the frequency and magnitude of future events in the light of geological principles. Of importance to nuclear waste disposal are longer term processes such as continental denudation and removal of materials by glacial erosion. Constant testing of projections will allow the practical limits of predicting geological events to be defined. 11 refs

Digital Geologic Map Database of Medicine Lake Volcano, Northern California

Science.gov (United States)

Ramsey, D. W.; Donnelly-Nolan, J. M.; Felger, T. J.

2010-12-01

Medicine Lake volcano, located in the southern Cascades ~55 km east-northeast of Mount Shasta, is a large rear-arc, shield-shaped volcano with an eruptive history spanning nearly 500 k.y. Geologic mapping of Medicine Lake volcano has been digitally compiled as a spatial database in ArcGIS. Within the database, coverage feature classes have been created representing geologic lines (contacts, faults, lava tubes, etc.), geologic unit polygons, and volcanic vent location points. The database can be queried to determine the spatial distributions of different rock types, geologic units, and other geologic and geomorphic features. These data, in turn, can be used to better understand the evolution, growth, and potential hazards of this large, rear-arc Cascades volcano. Queries of the database reveal that the total area covered by lavas of Medicine Lake volcano, which range in composition from basalt through rhyolite, is about 2,200 km2, encompassing all or parts of 27 U.S. Geological Survey 1:24,000-scale topographic quadrangles. The maximum extent of these lavas is about 80 km north-south by 45 km east-west. Occupying the center of Medicine Lake volcano is a 7 km by 12 km summit caldera in which nestles its namesake, Medicine Lake. The flanks of the volcano, which are dotted with cinder cones, slope gently upward to the caldera rim, which reaches an elevation of nearly 2,440 m. Approximately 250 geologic units have been mapped, only half a dozen of which are thin surficial units such as alluvium. These volcanic units mostly represent eruptive events, each commonly including a vent (dome, cinder cone, spatter cone, etc.) and its associated lava flow. Some cinder cones have not been matched to lava flows, as the corresponding flows are probably buried, and some flows cannot be correlated with vents. The largest individual units on the map are all basaltic in composition, including the late Pleistocene basalt of Yellowjacket Butte (296 km2 exposed), the largest unit on the

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

Protein sequence comparison and protein evolution

Energy Technology Data Exchange (ETDEWEB)

Pearson, W.R. [Univ. of Virginia, Charlottesville, VA (United States). Dept. of Biochemistry

1995-12-31

This tutorial was one of eight tutorials selected to be presented at the Third International Conference on Intelligent Systems for Molecular Biology which was held in the United Kingdom from July 16 to 19, 1995. This tutorial examines how the information conserved during the evolution of a protein molecule can be used to infer reliably homology, and thus a shared proteinfold and possibly a shared active site or function. The authors start by reviewing a geological/evolutionary time scale. Next they look at the evolution of several protein families. During the tutorial, these families will be used to demonstrate that homologous protein ancestry can be inferred with confidence. They also examine different modes of protein evolution and consider some hypotheses that have been presented to explain the very earliest events in protein evolution. The next part of the tutorial will examine the technical aspects of protein sequence comparison. Both optimal and heuristic algorithms and their associated parameters that are used to characterize protein sequence similarities are discussed. Perhaps more importantly, they survey the statistics of local similarity scores, and how these statistics can both be used to improve the selectivity of a search and to evaluate the significance of a match. They them examine distantly related members of three protein families, the serine proteases, the glutathione transferases, and the G-protein-coupled receptors (GCRs). Finally, the discuss how sequence similarity can be used to examine internal repeated or mosaic structures in proteins.

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.

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

Shock modification and chemistry and planetary geologic processes

International Nuclear Information System (INIS)

Boslough, M.S.

1991-01-01

This paper brings the rapid advances on shock processing of materials to the attention of Earth scientists, and to put these advances in the context of planetary geologic processes. Most of the recent research in this area has been directed at materials modification an synthesis, and the information gained has direct relevance to shock effects in nature. Research on various types of shock modification and chemistry in both naturally and experimentally shocked rocks and minerals is reviewed, and where appropriate their significance to planetary processes is indicated. As a case study, the surface of Mars is suggested as a place where conditions are optimal for shock processing to be a dominant factor. The various mechanisms of shock modification, activation, synthesis and decomposition are all proposed as major contributors to the evolution of chemical, mineralogical, and physical properties of the Martian regolith

Geological disposal of high-level radioactive waste and geological environment in Japan

International Nuclear Information System (INIS)

Shimizu, Kazuhiko; Seo, Toshihiro; Yshida, Hidekazu

2001-01-01

The geological environment has two main functions in terms of ensuring the safety of geological disposal of high-level radioactive waste. One relates to the fundamental long-term stability of the site and the other to the properties of the host rock formations and groundwaters which facilitate the emplacement of the engineered barrier system and act as a natural barrier. In this connection, the feasibility of selecting a geological environment in Japan which is appropriate for geological disposal was discussed, based on findings obtained from case studies and field measurements. Considering long-term stability of the site, it is important to understand the effects and spatial distributions of the natural phenomena such as fault movement, volcanic activity, uplift/denudation and climatic/sea-level changes. Fault movement and volcanic activity are relatively localized phenomena, and can be avoided by considering only areas that are sufficiently remote from existing volcanoes and major active faults for these phenomena to have a negligible probability of causing significant effects. Uplift/denudation and climatic/sea-level changes are gradual phenomena and are more ubiquitous. It is, nevertheless, possible to estimate future trends by extrapolating the past changes into the future, and then to identify areas that may not be affected significantly by such phenomena. Considering the properties of the host rocks and groundwaters, it can be understood, from the presently available data, that deep groundwater in Japan generally flows slowly and its chemistry is in a reduced state. The data also suggest that deep rock masses, where the ground temperature is acceptably low and the rock pressure is almost homogeneous, are widely located throughout Japan. Based on the examination of the geological environment in Japan, it is possible to discuss the requirements for the geological environment to be considered and the investigations to be performed during the site selection

Geostatistics: a common link between medical geography, mathematical geology, and medical geology.

Science.gov (United States)

Goovaerts, P

2014-08-01

Since its development in the mining industry, geostatistics has emerged as the primary tool for spatial data analysis in various fields, ranging from earth and atmospheric sciences to agriculture, soil science, remote sensing, and more recently environmental exposure assessment. In the last few years, these tools have been tailored to the field of medical geography or spatial epidemiology, which is concerned with the study of spatial patterns of disease incidence and mortality and the identification of potential 'causes' of disease, such as environmental exposure, diet and unhealthy behaviours, economic or socio-demographic factors. On the other hand, medical geology is an emerging interdisciplinary scientific field studying the relationship between natural geological factors and their effects on human and animal health. This paper provides an introduction to the field of medical geology with an overview of geostatistical methods available for the analysis of geological and health data. Key concepts are illustrated using the mapping of groundwater arsenic concentration across eleven Michigan counties and the exploration of its relationship to the incidence of prostate cancer at the township level.

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

Geological history of uranium

International Nuclear Information System (INIS)

Niini, Heikki

1989-01-01

Uranium is widely distributed in continental geological environments. The order of magnitude of uranium abundance in felsitic igneous rocks is 2-15 ppm, whereas it is less than 1 ppm in mafic rocks. Sedimentary rocks show a large range: from less than 0.1 ppm U in certain evaporites to over 100 ppm in phosphate rocks and organogenic matter. The content of U in seawater varies from 0.0005 to 0.005 ppm. The isotopic ratio U-238/U-235 is presently 137.5+-0.5, having gradually increased during geological time. The third natural isotope is U-234. On the basis of three fundamental economic criteria for ore reserves assessment (geological assurance, technical feasibility, and the grade and quantity of the deposits), the author finally comes to the following conclusions: Although the global uranium ores are not geologically renewable but continuously mined, they still, due to exploration and technical development, will tend to progressively increase for centuries to come

Geology of the Tyrrhenus Mons Lava Flow Field, Mars

Science.gov (United States)

Crown, David A.; Mest, Scott C.

2014-11-01

The ancient, eroded Martian volcano Tyrrhenus Mons exhibits a central caldera complex, layered flank deposits dissected by radial valleys, and a 1000+ km-long flow field extending to the southwest toward Hellas Planitia. Past studies suggested an early phase of volcanism dominated by large explosive eruptions followed by subsequent effusive activity at the summit and to the southwest. As part of a new geologic mapping study of northeast Hellas, we are examining the volcanic landforms and geologic evolution of the Tyrrhenus Mons flow field, including the timing and nature of fluvial activity and effects on volcanic units. New digital geologic mapping incorporates THEMIS IR (100 m/pixel) and CTX (5 m/pixel) images as well as constraints from MOLA topography.Mapping results to-date include delineation of the boundaries of the flow field, identification and mapping of volcanic and erosional channels within the flow field, and mapping and analysis of lava flow lobes. THEMIS IR and CTX images allow improved discrimination of the numerous flow lobes that are observed in the flow field, including refinement of the margins of previously known flows and identification of additional and smaller lobes. A prominent sinuous rille extending from Tyrrhenus Mons’ summit caldera is a major feature that supplied lava to the flow field. Smaller volcanic channels are common throughout the flow field; some occur in segments along crests of local topographic highs and may delineate lava tubes. In addition to volcanic channels, the flow field surface is characterized by several types of erosional channels, including wide troughs with scour marks, elongate sinuous channels, and discontinuous chains of elongate pits and troughs. High-resolution images reveal the widespread and significant effects of fluvial activity in the region, and further mapping studies will examine spatial and temporal interactions between volcanism and fluvial processes.

The geology of the Falkland Islands

OpenAIRE

Aldiss, D.T.; Edwards, E.J.

1999-01-01

This report is complementary to the 1:250 000 scale geological map of the Falkland Islands compiled in 1998. The report and map are products of the Falkland Islands Geological Mapping Project (1996-1998). Geological observation and research in the Islands date from 1764. The Islands were visited during two pioneering scientific cruises in the 19th century. Subsequently, many scientists visited en route to the Antarctic or Patagonia. Geological affinities to other parts of the sout...

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.

Heterogeneity-enhanced gas phase formation in shallow aquifers during leakage of CO2-saturated water from geologic sequestration sites

DEFF Research Database (Denmark)

Plampin, Michael R.; Lassen, Rune Nørbæk; Sakaki, Toshihiro

2014-01-01

sands. Soil moisture sensors were utilized to observe the formation of gas phase near the porous media interfaces. Results indicate that the conditions under which heterogeneity controls gas phase evolution can be successfully predicted through analysis of simple parameters, including the dissolved CO2......, it is important to understand the physical processes that CO2 will undergo as it moves through naturally heterogeneous porous media formations. Previous studies have shown that heterogeneity can enhance the evolution of gas phase CO2 in some cases, but the conditions under which this occurs have not yet been...... quantitatively defined, nor tested through laboratory experiments. This study quantitatively investigates the effects of geologic heterogeneity on the process of gas phase CO2 evolution in shallow aquifers through an extensive set of experiments conducted in a column that was packed with layers of various test...

A Geospatial Information Grid Framework for Geological Survey.

Science.gov (United States)

Wu, Liang; Xue, Lei; Li, Chaoling; Lv, Xia; Chen, Zhanlong; Guo, Mingqiang; Xie, Zhong

2015-01-01

The use of digital information in geological fields is becoming very important. Thus, informatization in geological surveys should not stagnate as a result of the level of data accumulation. The integration and sharing of distributed, multi-source, heterogeneous geological information is an open problem in geological domains. Applications and services use geological spatial data with many features, including being cross-region and cross-domain and requiring real-time updating. As a result of these features, desktop and web-based geographic information systems (GISs) experience difficulties in meeting the demand for geological spatial information. To facilitate the real-time sharing of data and services in distributed environments, a GIS platform that is open, integrative, reconfigurable, reusable and elastic would represent an indispensable tool. The purpose of this paper is to develop a geological cloud-computing platform for integrating and sharing geological information based on a cloud architecture. Thus, the geological cloud-computing platform defines geological ontology semantics; designs a standard geological information framework and a standard resource integration model; builds a peer-to-peer node management mechanism; achieves the description, organization, discovery, computing and integration of the distributed resources; and provides the distributed spatial meta service, the spatial information catalog service, the multi-mode geological data service and the spatial data interoperation service. The geological survey information cloud-computing platform has been implemented, and based on the platform, some geological data services and geological processing services were developed. Furthermore, an iron mine resource forecast and an evaluation service is introduced in this paper.

The laboratories of geological studies

International Nuclear Information System (INIS)

1994-01-01

This educational document comprises 4 booklets in a folder devoted to the presentation of the ANDRA's activities in geological research laboratories. The first booklet gives a presentation of the missions of the ANDRA (the French agency for the management of radioactive wastes) in the management of long life radioactive wastes. The second booklet describes the approach of waste disposal facilities implantation. The third booklet gives a brief presentation of the scientific program concerning the underground geologic laboratories. The last booklet is a compilation of questions and answers about long-life radioactive wastes, the research and works carried out in geologic laboratories, the public information and the local socio-economic impact, and the storage of radioactive wastes in deep geological formations. (J.S.)

Geoethics and Forensic Geology

Science.gov (United States)

Donnelly, Laurance

2017-04-01

The International Union of Geological Sciences (IUGS), Initiative on Forensic Geology (IFG) was set up in 2011 to promote and develop the applications of geology to policing and law enforcement throughout the world. This includes the provision of crime scene examinations, searches to locate graves or items of interest that have been buried beneath the ground surface as part of a criminal act and geological trace analysis and evidence. Forensic geologists may assist the police and law enforcement in a range of ways including for example; homicide, sexual assaults, counter terrorism, kidnapping, humanitarian incidents, environmental crimes, precious minerals theft, fakes and fraudulent crimes. The objective of this paper is to consider the geoethical aspects of forensic geology. This includes both delivery to research and teaching, and contribution to the practical applications of forensic geology in case work. The case examples cited are based on the personal experiences of the authors. Often, the technical and scientific aspect of forensic geology investigation may be the most straightforward, after all, this is what the forensic geologist has been trained to do. The associated geoethical issues can be the most challenging and complex to manage. Generally, forensic geologists are driven to carry-out their research or case work with integrity, honesty and in a manner that is law abiding, professional, socially acceptable and highly responsible. This is necessary in advising law enforcement organisations, society and the scientific community that they represent. As the science of forensic geology begins to advance around the world it is desirable to establish a standard set of principles, values and to provide an agreed ethical a framework. But what are these core values? Who is responsible for producing these? How may these become enforced? What happens when geoethical standards are breached? This paper does not attempt to provide all of the answers, as further work

49 CFR 801.59 - Geological records.

Science.gov (United States)

2010-10-01

... 49 Transportation 7 2010-10-01 2010-10-01 false Geological records. 801.59 Section 801.59... PUBLIC AVAILABILITY OF INFORMATION Exemption From Public Disclosure § 801.59 Geological records. Pursuant to 5 U.S.C. 552(b)(9), records concerning geological wells are exempt from public disclosure. ...

Postseismic afterslip 30 years after the 1978 Tabas-e-Golshan (Iran) earthquake: observations and implications for the geological evolution of thrust belts

Science.gov (United States)

Copley, Alex

2014-05-01

This paper presents InSAR observations of postseismic afterslip occurring up to 30 yr after the Mw7.3 1978 Tabas-e-Golshan thrust-faulting earthquake in eastern Iran. Comparison of the surface motion from 1996 to 1999 with that from 2003 to 2010, along with information provided by the Quaternary-averaged slip rates of faults in the region, suggests that the imaged slip is transient and decaying through time. Models of the surface deformation field imply slip on faults dipping at 55 ± 10°, reaching from the surface to depths of 4-5 km, and slipping at 5 ± 1 mm yr-1. These faults outcrop on the margins of low anticlinal hills composed of actively uplifting Neogene deposits. When compared with the previously studied main shock focal parameters (slip on a plane dipping at 16 ± 5° with a centroid depth of ˜9 km), and the aftershock distribution (a band at ˜6-14 km), the InSAR results imply postseismic slip on a high-angle thrust ramp connecting the surface anticlines to the coseismic low-angle fault plane at depth. In one location, both a thrust ramp and also a backthrust are postseismically active. The InSAR observations demonstrate the role of postseismic afterslip in the growth of these commonly observed thrust belt geometries, and highlight that deformation throughout the seismic cycle can contribute to the geological evolution of regions of active faulting.

Palinspastic reconstruction and geological evolution of Permian residual marine basins bordering China and Mongolia

Directory of Open Access Journals (Sweden)

Gen-Yao Wu

2014-04-01

Full Text Available One main feature of the tectono-paleogeographic evolution of the southern branch of the Paleo-Asian Ocean was that there developed residual marine basins in former backarc/forearc regions after the disappearance of oceanic crust. The paper illustrates the viewpoint taking the evolution of Dalandzadgad and Solonker oceanic basins as examples. The Dalandzadgad ocean subducted southwards during the Silurian-Devonian, created an intra-oceanic arc and a backarc basin in southern Mongolia. In addition, a continent marginal arc formed along the national boundary between China and Mongolia, the south of which was a backarc basin. The oceanic basin closed and arc–arc (continent collision occurred during the early Early Permian, followed by two residual marine basins developing in the former backarc regions, named the South Gobi Basin in southern Mongolia and the Guaizihu Basin in western Inner Mongolia. The Solonker ocean subducted southwards and finally disappeared during the early Middle Permian. Afterwards, two residual marine basins occurred in northern China, the Zhesi Basin being situated in the former backarc region and the Wujiatun Basin in the former forearc region. The late Middle Permian was the most optimum period for the developing residual marine basins, when they covered a vast area. The basin evolution differentiated during the early Late Permian, with a general trend of uplift in the east and of subsidence in the west. The Upper Permian in the South Gobi Basin was characterized by coal-bearing strata hosting economically valuable coal fields. A transgression invaded westwards and the Chandmani-Bayanleg Basin was created in southwest Mongolia during the middle-late stage of the Late Permian. Correspondingly, the coal formation entered a flourishing time, with thick coal beds and sedimentary interbeds. All of these basins, namely, both the marine and nonmarine residual basins, reversed and closed by the end of Permian.

Earth System Stability Through Geologic Time

Science.gov (United States)

Rothman, D.; Bowring, S. A.

2015-12-01

Five times in the past 500 million years, mass extinctions haveresulted in the loss of greater than three-fourths of living species.Each of these events is associated with significant environmentalchange recorded in the carbon-isotopic composition of sedimentaryrocks. There are also many such environmental events in the geologicrecord that are not associated with mass extinctions. What makes themdifferent? Two factors appear important: the size of theenvironmental perturbation, and the time scale over which it occurs.We show that the natural perturbations of Earth's carbon cycle during thepast 500 million years exhibit a characteristic rate of change overtwo orders of magnitude in time scale. This characteristic rate isconsistent with the maximum rate that limits quasistatic (i.e., nearsteady-state) evolution of the carbon cycle. We identify this rate withmarginal stability, and show that mass extinctions occur on the fast,unstable side of the stability boundary. These results suggest thatthe great extinction events of the geologic past, and potentially a"sixth extinction" associated with modern environmental change, arecharacterized by common mechanisms of instability.

Geologic Mapping of the Lunar South Pole, Quadrangle LQ-30: Volcanic History and Stratigraphy of Schroedinger Basin

Science.gov (United States)

Mest, S. C.; Berman, D. C.; Petro, N. E.

2009-01-01

In this study we use recent images and topographic data to map the geology and geomorphology of the lunar South Pole quadrangle (LQ-30) at 1:2.5M scale [1-4] in accordance with the Lunar Geologic Mapping Program. Mapping of LQ-30 began during Mest's postdoctoral appointment and has continued under the PG&G Program, from which funding became available in February 2009. Preliminary map-ping and analyses have been done using base materials compiled by Mest, but properly mosaicked and spatially registered base materials are being compiled by the USGS and should be received by the end of June 2009. The overall objective of this research is to constrain the geologic evolution of the lunar South Pole (LQ-30: 60deg -90deg S, 0deg - +/-180deg ) with specific emphasis on evaluation of a) the regional effects of basin formation on the structure and composition of the crust and b) the spatial distribution of ejecta, in particular resulting from formation of the South Pole-Aitken (SPA) basin and other large basins. Key scientific objectives include: 1) Constraining the geologic history of the lunar South Pole and examining the spatial and temporal variability of geologic processes within the map area. 2) Constraining the vertical and lateral structure of the lunar regolith and crust, assessing the distribution of impact-generated materials, and determining the timing and effects of major basin-forming impacts on crustal structure and stratigraphy in the map area. And 3) assessing the distribution of resources (e.g., H, Fe, Th) and their relationships with surface materials.

Geochemical analysis of Minho Estuary sedimentary record and its contribution to palaeoenvironmental evolution

International Nuclear Information System (INIS)

Ivarez-Iglesias, P. A.

2009-01-01

Two sediment cores (∼30 m long) were retrieved at the mouth of the Minho Estuary to assess its palaeoenvironmental evolution for the last millennia. Samples were characterized by Energy-Dispersive X-Ray Fluorescence Spectrometry and Instrumental Neutron Activation Analysis, complemented by sedimentological analyses. Provenance of major and trace element contents (lithogenic or biogenic, continental or marine) is assessed. The influence of grain size effect on total element concentration is discussed. Most of the samples present a negative Eu anomaly. Sedimentological and geochemical parameters allow differentiating four geological units - fluvial, marine, estuarine and sand barrier - which reflects the temporal evolution of the Minho Estuary. (author)

2005 dossier. ANDRA's researches on the geological disposal of high-level and long-lived radioactive wastes. Results and perspectives

International Nuclear Information System (INIS)

2005-06-01

This document makes a status of the researches carried out by the French national agency of radioactive wastes (ANDRA) about the geologic disposal of high-level and long-lived radioactive wastes in deep geologic formations (argilites and granites). Content: 1 - Research on deep disposal of radioactive waste: general interest task: Legislative framework, ANDRA scientific objectives, Inspections and assessments; 2 - Designing a safe and reversible disposal system: Repository safety, Reversibility: an essential requirement; 3 - Clay Research on a repository in a clay formation, A long research programme, Dossier 2005 Argile; 4 - Meuse/Haute-Marne site clay: Expected properties of the rock formation, Choice of argillite, Meuse/Haute-Marne site, Conclusions from 10 years of research at the Meuse/Haute-Marne site; 5 - Repository installations: Safe and reversible architecture, Disposal of B waste, Disposal of C waste, Possible disposal of spent fuel (CU); 6 - The disposal facility in operation: From waste packages reception to their disposal in cells, Stages of the progressive closure of engineered structures; 7 - Reversible management: Freedom of choice for future generations, Various closure stages; 8 - Long-term evolution of the repository: Apprehending the repository complexity Main evolutions expected, Slow and limited release of radioactive substances; 9 - Repository safety and impact on man: Several evolution scenarios, Normal evolution, Altered evolution; 10 - Granite Research on a repository in a granite formation: A global approach, Scientific co-operations, Dossier 2005 Granite; 11 - Characteristics of French granite formations: What properties are required for a repository?, Different types of granite formations; 12 - Repository installations: Repository design adapted to granite fractures, Clay seals to prevent water flows, Waste disposal packages ensuring long-term leak-tightness, Physical and chemical environment favourable for waste packages, Architecture

Modeling Protein Evolution

Science.gov (United States)

Goldstein, Richard; Pollock, David

The study of biology is fundamentally different from many other scientific pursuits, such as geology or astrophysics. This difference stems from the ubiquitous questions that arise about function and purpose. These are questions concerning why biological objects operate the way they do: what is the function of a polymerase? What is the role of the immune system? No one, aside from the most dedicated anthropist or interventionist theist, would attempt to determine the purpose of the earth's mantle or the function of a binary star. Among the sciences, it is only biology in which the details of what an object does can be said to be part of the reason for its existence. This is because the process of evolution is capable of improving an object to better carry out a function; that is, it adapts an object within the constraints of mechanics and history (i.e., what has come before). Thus, the ultimate basis of these biological questions is the process of evolution; generally, the function of an enzyme, cell type, organ, system, or trait is the thing that it does that contributes to the fitness (i.e., reproductive success) of the organism of which it is a part or characteristic. Our investigations cannot escape the simple fact that all things in biology (including ourselves) are, ultimately, the result of an evolutionary process.

The prehistoric Vajont rockslide: An updated geological model

Science.gov (United States)

Paronuzzi, Paolo; Bolla, Alberto

2012-10-01

This study presents the detailed reconstruction of the entire structure of the prehistoric Vajont rockslide (about 270-300 million m3 of rocks and debris) for the first time, describing the complex geometry and the characteristic superimposition of distinct rigid blocks on a very thick shear zone. The prehistoric Vajont rockslide was characterized by an enormous 'en masse' motion of a rigid overlying rock mass (100-130 m thick) that moved downslope, sliding onto a very thick shear zone (40-50 m thick, on average) made up of a chaotic assemblage of blocks, limestone angular gravel, and high plasticity clays (montmorillonitic clays). Coarse loose sediments, still exposed on the 9 October 1963 detachment surface, are always associated with large blocks made of strongly fractured rock masses (Fonzaso Formation: middle-upper Jurassic) preserving the stratification. The blocks of stratified and folded limestone sequences appear to be 'sheared off' from the underlying bedrock and can be considered as displaced rock masses planed off by the motion of the overlying rigid rock mass ('rock mass shavings'). The prehistoric Vajont rockslide was characterized by a multistage failure with a marked retrogressive evolution. The first rupture (Pian del Toc block) rapidly destabilized the upper slope, mobilizing a second rock mass block (Pian della Pozza block) that, in turn, determined the multiple rupture of the revealed shear zone material (Massalezza lobe). Even if the exact timing of the different phases is not known, the entire multistaged failure process was very rapid. At the end of the multistage retrogressive failure, the slope morphology of the northern toe of Mt. Toc was drastically changed and the large failed rock mass settled into the preexisting Vajont Valley assuming the unusual chair-like geometry. The Vajont rockslide represents a very significant example on how a complex geological situation, if not adequately analyzed and reconstructed, can lead to dangerous

Palinspastic reconstruction and geological evolution of Jurassic basins in Mongolia and neighboring China

Directory of Open Access Journals (Sweden)

Wu Genyao

2013-07-01

Full Text Available The important event in Jurassic tectonics in Mongolia was the subduction and closure of the Mongolia-Okhotsk ocean; correspondingly, basin evolution can be divided into two main stages, related to the orogeny and collapse of the orogenic belt, respectively. The developing of Early–Middle Jurassic basins to the north of the ocean resulted from back-arc extension. The fossil sutures, from the China–SE Asia sub-continent to the south of the ocean, were rejuvenated by subduction-related orogeny; in addition, the Yanshanian intra-continental movement occurred. Three Early–Middle Jurassic molasse basins were developed by movement in Inner Mongolia, all of which stretched westwards (or northwards into Mongolia; therefore, the molasse basins in eastern and southern Mongolia had the same geometric and kinematic features as the basins in the Inner Mongolia. Owing to the collapse of the Mongolia-Okhotsk orogenic belt, a group of rift basins developed during the Late Jurassic. In eastern Mongolia, the NE orientated extensional basins were controlled by the neogenic NE-structure. The contemporary basins in southern Mongolia and the neighboring areas in China were constrained by remobilization (inherited activation of the latitudinal or ENE-directional basement structures. Three stages can be recognized in the evolution of the Early–Middle Jurassic basins after reversal; the basins also experienced four episodes of reformation.

Proposals of geological sites for L/ILW and HLW repositories. Geological background. Text volume

International Nuclear Information System (INIS)

2008-01-01

On April 2008, the Swiss Federal Council approved the conceptual part of the Sectoral Plan for Deep Geological Repositories. The Plan sets out the details of the site selection procedure for geological repositories for low- and intermediate-level waste (L/ILW) and high-level waste (HLW). It specifies that selection of geological siting regions and sites for repositories in Switzerland will be conducted in three stages, the first one (the subject of this report) being the definition of geological siting regions within which the repository projects will be elaborated in more detail in the later stages of the Sectoral Plan. The geoscientific background is based on the one hand on an evaluation of the geological investigations previously carried out by Nagra on deep geological disposal of HLW and L/ILW in Switzerland (investigation programmes in the crystalline basement and Opalinus Clay in Northern Switzerland, investigations of L/ILW sites in the Alps, research in rock laboratories in crystalline rock and clay); on the other hand, new geoscientific studies have also been carried out in connection with the site selection process. Formulation of the siting proposals is conducted in five steps: A) In a first step, the waste inventory is allocated to the L/ILW and HLW repositories; B) The second step involves defining the barrier and safety concepts for the two repositories. With a view to evaluating the geological siting possibilities, quantitative and qualitative guidelines and requirements on the geology are derived on the basis of these concepts. These relate to the time period to be considered, the space requirements for the repository, the properties of the host rock (depth, thickness, lateral extent, hydraulic conductivity), long-term stability, reliability of geological findings and engineering suitability; C) In the third step, the large-scale geological-tectonic situation is assessed and large-scale areas that remain under consideration are defined. For the L

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

Gravity derived depth to basement in Santiago Basin, Chile: implications for its geological evolution, hydrogeology, low enthalpy geothermal, soil characterization and geo-hazards

OpenAIRE

Yáñez, Gonzalo; Muñoz, Mauricio; Flores-Aqueveque, Valentina; Bosch, Andrés

2015-01-01

A recording of 1,115 gravimetric stations, the review of 368 wells, and the petrophysics measurements of 106 samples from representative outcrops have been used for a comprehensive geological/geophysical study of Santiago Basin. 2.5D and 3D gravimetric modeling, constrained by regional geology, soil and bedrock densities, edge-basin outcrops, depth (minimum) to basement from wells, and detailed modeling of heterogeneous bedrock and midcrustal blocks, provided a well-constrained depth to basem...

Development and management of the knowledge base for the geological disposal technology. Annual report 2006

International Nuclear Information System (INIS)

Umeda, Koji; Oyama, Takuya; Kurosawa, Hideki; Semba, Takeshi; Takeuchi, Shinji; Tajikara, Masayoshi; Tsuruta, Tadahiko; Yasue, Ken-ichi; Ohi, Takao; Oda, Chie; Kamei, Gento; Kobayashi, Yasushi; Sasaki, Yasuo; Sawada, Atsushi; Taniguchi, Naoki; Tanai, Kenji; Naito, Morimasa; Nakayama, Masashi; Kuno, Yoshio; Fujita, Tomoo; Honda, Akira; Mihara, Morihiro; Miyahara, Kaname; Osawa, Hideaki; Fujishima, Atsushi; Kuji, Masayoshi; Saito, Haruo; Sanada, Hiroyuki; Niizato, Tadafumi; Funaki, Hironori; Maekawa, Keisuke; Fujiwara, Kenso

2007-12-01

To increase technical reliability in geological disposal technology of high-level radioactive waste, JAEA have been conducting R and D activities in the fields in the repository engineering, performance assessment (PA) of the geological disposal system, and geoscientific study. In the field of R and D on the repository engineering, laboratory experimental studies at Tokai Research Center are carried out by engineering-scale and non-radiogenic experiments. The studies on performance assessment include more realistic model development with extensive computer analyses and acquisition of basic data concerning the chemical properties and migration behavior of radionuclides under geological disposal conditions. The information obtained from the Underground Research Laboratories (URLs) is used to provide a realistic condition of geological environments for these studies. The R and D studies are also carried out for TRU waste. A particular JAEA R and D activity is to promote the projects of two Underground Research Laboratories (URLs): one at Mizunami city, in crystalline rock and the other at Horonobe town, in sedimentary rock. In the present stage (2nd R and D phase) of the URL projects, the investigation are being carried out during the excavation of shafts and drifts. Data obtained from the investigations will serve to verify and refine the results from the surface-based investigations and characterize the evolution of the geological environment during drift excavation. The research on natural processes, such as fault and volcanic activities, is also conducted to provide better understanding of long-term stability on the geological environment. JAEA has initiated a project to develop the next generation of novel knowledge management system (KMS) to develop and manage the technical knowledge base for supporting implementers and regulators. This knowledge base includes all technical achievements by the JAEA as well as know-how and experience which have been accumulated

Intelligent Learning for Knowledge Graph towards Geological Data

Directory of Open Access Journals (Sweden)

Yueqin Zhu

2017-01-01

Full Text Available Knowledge graph (KG as a popular semantic network has been widely used. It provides an effective way to describe semantic entities and their relationships by extending ontology in the entity level. This article focuses on the application of KG in the traditional geological field and proposes a novel method to construct KG. On the basis of natural language processing (NLP and data mining (DM algorithms, we analyze those key technologies for designing a KG towards geological data, including geological knowledge extraction and semantic association. Through this typical geological ontology extracting on a large number of geological documents and open linked data, the semantic interconnection is achieved, KG framework for geological data is designed, application system of KG towards geological data is constructed, and dynamic updating of the geological information is completed accordingly. Specifically, unsupervised intelligent learning method using linked open data is incorporated into the geological document preprocessing, which generates a geological domain vocabulary ultimately. Furthermore, some application cases in the KG system are provided to show the effectiveness and efficiency of our proposed intelligent learning approach for KG.

The geotectonic evolution of southern part of Sao Francisco Craton, based in geochronologic interpretation

International Nuclear Information System (INIS)

Teixeira, W.

1985-01-01

Interpretation of available radiometric data from poly metamorphic terranes of southern part of the Sao Francisco Craton demonstrates the importance of geochronology as a tool in the study of ancient crustal evolution. In addition, radiometric study of basic intrusive magmatism helps define the most important epochs of crustal rifting during the Proterozoic. The definition of the southern border of the cratonic area based on distinctive age patterns of the geochronological provinces is also discussed. Finally, the geochronologic evolution of the Bambui platform cover is presented. Approximately 250 radiometric age determinations (Rb-Sr, K-Ar and Pb-Pb methods) were interpreted principally through the use of iso chronic diagrams. The geologic history tectonomagnetic events identified in this study is compared to the crustal evolution of similar segments of the Sao Francisco Craton and elsewhere. (author)

Digital Geologic Mapping and Integration with the Geoweb: The Death Knell for Exclusively Paper Geologic Maps

Science.gov (United States)

House, P. K.

2008-12-01

The combination of traditional methods of geologic mapping with rapidly developing web-based geospatial applications ('the geoweb') and the various collaborative opportunities of web 2.0 have the potential to change the nature, value, and relevance of geologic maps and related field studies. Parallel advances in basic GPS technology, digital photography, and related integrative applications provide practicing geologic mappers with greatly enhanced methods for collecting, visualizing, interpreting, and disseminating geologic information. Even a cursory application of available tools can make field and office work more enriching and efficient; whereas more advanced and systematic applications provide new avenues for collaboration, outreach, and public education. Moreover, they ensure a much broader audience among an immense number of internet savvy end-users with very specific expectations for geospatial data availability. Perplexingly, the geologic community as a whole is not fully exploring this opportunity despite the inevitable revolution in portends. The slow acceptance follows a broad generational trend wherein seasoned professionals are lagging behind geology students and recent graduates in their grasp of and interest in the capabilities of the geoweb and web 2.0 types of applications. Possible explanations for this include: fear of the unknown, fear of learning curve, lack of interest, lack of academic/professional incentive, and (hopefully not) reluctance toward open collaboration. Although some aspects of the expanding geoweb are cloaked in arcane computer code, others are extremely simple to understand and use. A particularly obvious and simple application to enhance any field study is photo geotagging, the digital documentation of the locations of key outcrops, illustrative vistas, and particularly complicated geologic field relations. Viewing geotagged photos in their appropriate context on a virtual globe with high-resolution imagery can be an

Report on the geological and geomorphological field operation in the Amundsen Bay region, western Enderby Land, 1998-99 (JARE-40

Directory of Open Access Journals (Sweden)

Yoichi Motoyoshi

1999-11-01

Full Text Available The 40th Japanese Antarctic Research Expedition (JARE-40 conducted field operations on geology and geomorphology in the Amundsen Bay region, Enderby Land, for 34 days from December 21,1998 to January 23,1999. This was a part of the 5-year SEAL (Structure and Evolution of East Antarctic Lithosphere project, and two helicopters were installed for field support. Geological and geomorphological teams established base camps at Tonagh Island and Mt. Riiser-Larsen, respectively, and tried to conduct surveys in western Enderby Land. At the early stage of the operation, an unexpected gusty wind destroyed one of the helicopters at Tonagh Island, and planned surveys have not been completed. This report gives details of the logistics including planning, preparation and results.

Evolution of the solar 'constant'

Energy Technology Data Exchange (ETDEWEB)

Newman, M J

1980-06-01

Variations in solar luminosity over geological time are discussed in light of the effect of the solar constant on the evolution of life on earth. Consideration is given to long-term (5 - 7% in a billion years) increases in luminosity due to the conversion of hydrogen into helium in the solar interior, temporary enhancements to solar luminosity due to the accretion of matter from the interstellar medium at intervals on the order of 100 million years, and small-amplitude rapid fluctuations of luminosity due to the stochastic nature of convection on the solar surface. It is noted that encounters with dense interstellar clouds could have had serious consequences for life on earth due to the peaking of the accretion-induced luminosity variation at short wavelengths.

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)

Geologic mapping of the Hi’iaka and Shamshu regions of Io

Science.gov (United States)

Bunte, Melissa K.; Williams, David A.; Greeley, Ronald; Jaeger, Windy L.

2010-06-01

pull-apart basins. With comparison to other regional maps of Io and global studies of paterae and mountains, this work provides insight into the general geologic evolution of Io.

Paleomagnetic and geochronologic constraints on the geodynamic evolution of the Central Dinarides

Science.gov (United States)

de Leeuw, Arjan; Mandic, Oleg; Krijgsman, Wout; Kuiper, Klaudia; Hrvatović, Hazim

2013-04-01

The geodynamic evolution of the Dinaride Mountains of southeastern Europe is relatively poorly understood, especially in comparison with the neighbouring Alps and Carpathians. We have constructed a new chronostratigraphy for the post-orogenic intra-montane basins of the Central Dinarides based on paleomagnetic and 40Ar/39Ar age data. Our results provide time constraints on the formation of these basins and elucidate their subsequent evolution. This is a fundamental step towards a better understanding of the late stage geodynamic evolution of the Central Dinarides. Our paleomagnetic results moreover indicate that the Dinarides have not experienced significant tectonic rotation since the late Oligocene. This implies that the Dinarides were decoupled from the adjacent Adria and the Tisza-Dacia Mega-Units that both underwent major rotation. We provide a reference frame for our rotation results through a review of Late Jurassic to Miocene paleomagnetic data, which elucidates spatial and tectonic rotation patterns in the Adria-Dinarides collision zone. The obtained results significantly improve our insight in the evolution of the Central Dinarides and help reconcile structural geological and paleomagnetic rotation estimates.

Geology of the North Sea and Skagerrak

Energy Technology Data Exchange (ETDEWEB)

Michelsen, O. [ed.

1995-12-31

The Marine Geology Unit of the Department of Earth Sciences organized the second Marine Geology symposium at Aarhus University, 7-8 October 1993. The intention was to bring together people working especially with the geology of the North Sea and Skagerrak. Approximately 60 people from different Danish and Norwegian institutions attended the symposium. 28 oral presentations were given and 2 posters presented. A large range of geological topics was covered, embracing biostratigraphy, sequence stratigraphy, sedimentology and structural geology. The majority of the presentations dealt with Quaternary geology and Cenozoic sequence stratigraphy, but also Jurassic and Lower Cretaceous stratigraphy was treated. Studies from the major part of the Danish sector were presented, spanning from Bornholm to the central North Sea, and further into the Norwegian North Sea sector. (au)

Evolution of Ore Deposits and Technology Transfer Project: Isotope and Chemical Methods in Support of the U.S. Geological Survey Science Strategy, 2003-2008

Science.gov (United States)

Rye, Robert O.; Johnson, Craig A.; Landis, Gary P.; Hofstra, Albert H.; Emsbo, Poul; Stricker, Craig A.; Hunt, Andrew G.; Rusk, Brian G.

2010-01-01

Principal functions of the U.S. Geological Survey (USGS) Mineral Resources Program are providing assessments of the location, quantity, and quality of undiscovered mineral deposits, and predicting the environmental impacts of exploration and mine development. The mineral and environmental assessments of domestic deposits are used by planners and decisionmakers to improve the stewardship of public lands and public resources. Assessments of undiscovered mineral deposits on a global scale reveal the potential availability of minerals to the United States and other countries that manufacture goods imported to the United States. These resources are of fundamental relevance to national and international economic and security policy in our globalized world economy. Performing mineral and environmental assessments requires that predictions be made of the likelihood of undiscovered deposits. The predictions are based on geologic and geoenvironmental models that are constructed for the diverse types of mineral deposits from detailed descriptions of actual deposits and detailed understanding of the processes that formed them. Over the past three decades the understanding of ore-forming processes has benefited greatly from the integration of laboratory-based geochemical tools with field observations and other data sources. Under the aegis of the Evolution of Ore Deposits and Technology Transfer Project (referred to hereinafter as the Project), a 5-year effort that terminated in 2008, the Mineral Resources Program provided state-of-the-art analytical capabilities to support applications of several related geochemical tools to ore-deposit-related studies. The analytical capabilities and scientific approaches developed within the Project have wide applicability within Earth-system science. For this reason the Project Laboratories represent a valuable catalyst for interdisciplinary collaborations of the type that should be formed in the coming years for the United States to meet

Geology at Yucca Mountain

International Nuclear Information System (INIS)

Anon.

1993-01-01

Both advocates and critics disagree on the significance and interpretation of critical geological features which bear on the safety and suitability of Yucca Mountain as a site for the construction of a high-level radioactive waste repository. Critics believe that there is sufficient geological evidence to rule the site unsuitable for further investigation. Some advocates claim that there is insufficient data and that investigations are incomplete, while others claim that the site is free of major obstacles. We have expanded our efforts to include both the critical evaluations of existing geological and geochemical data and the collection of field data and samples for the purpose of preparing scientific papers for submittal to journals. Summaries of the critical reviews are presented in this paper

Geology behind nuclear fission technology

International Nuclear Information System (INIS)

Dhana Raju, R.

2005-01-01

Geology appears to have played an important role of a precursor to Nuclear Fission Technology (NFT), in the latter's both birth from the nucleus of an atom of and most important application as nuclear power extracted from Uranium (U), present in its minerals. NFT critically depends upon the availability of its basic raw material, viz., nuclear fuel as U and/ or Th, extracted from U-Th minerals of specific rock types in the earth's crust. Research and Development of the Nuclear Fuel Cycle (NFC) depends heavily on 'Geology'. In this paper, a brief review of the major branches of geology and their contributions during different stages of NFC, in the Indian scenario, is presented so as to demonstrate the important role played by 'Geology' behind the development of NFT, in general, and NFC, in particular. (author)

Selected geomorphological methods assessing neotectonic evolution of the seismoactive Hronov-Poříčí Fault Zone

Czech Academy of Sciences Publication Activity Database

Stejskal, Vladimír; Štěpančíková, Petra; Vilímek, V.

2006-01-01

Roč. 6, č. 1 (2006), s. 14-22 ISSN 1335-9541 R&D Projects: GA ČR(CZ) GD205/05/H020 Institutional research plan: CEZ:AV0Z30460519 Keywords : Hronov-Poříčí Fault Zone * seismic activity * neotectonic evolution Subject RIV: DB - Geology ; Mineralogy

Characteristics of Chinese petroleum geology. Geological features and exploration cases of stratigraphic, foreland and deep formation traps

Energy Technology Data Exchange (ETDEWEB)

Jia, Chengzao [PetroChina Company Limited, Beijing (China)

2012-07-01

The first book of this subject in the recent 10 years. ''Characteristics of Chinese Petroleum Geology: Geological Features and Exploration Cases of Stratigraphic, Foreland and Deep Formation Traps'' systematically presents the progress made in petroleum geology in China and highlights the latest advances and achievements in oil/gas exploration and research, especially in stratigraphic, foreland and deep formation traps. The book is intended for researchers, practitioners and students working in petroleum geology, and is also an authoritative reference work for foreign petroleum exploration experts who want to learn more about this field in China.

No evidence for directional evolution of body mass in herbivorous theropod dinosaurs

Science.gov (United States)

Zanno, Lindsay E.; Makovicky, Peter J.

2013-01-01

The correlation between large body size and digestive efficiency has been hypothesized to have driven trends of increasing mass in herbivorous clades by means of directional selection. Yet, to date, few studies have investigated this relationship from a phylogenetic perspective, and none, to our knowledge, with regard to trophic shifts. Here, we reconstruct body mass in the three major subclades of non-avian theropod dinosaurs whose ecomorphology is correlated with extrinsic evidence of at least facultative herbivory in the fossil record—all of which also achieve relative gigantism (more than 3000 kg). Ordinary least-squares regressions on natural log-transformed mean mass recover significant correlations between increasing mass and geological time. However, tests for directional evolution in body mass find no support for a phylogenetic trend, instead favouring passive models of trait evolution. Cross-correlation of sympatric taxa from five localities in Asia reveals that environmental influences such as differential habitat sampling and/or taphonomic filtering affect the preserved record of dinosaurian body mass in the Cretaceous. Our results are congruent with studies documenting that behavioural and/or ecological factors may mitigate the benefit of increasing mass in extant taxa, and suggest that the hypothesis can be extrapolated to herbivorous lineages across geological time scales. PMID:23193135

Research on geological disposal

International Nuclear Information System (INIS)

Uchida, Masahiro

2011-01-01

The aims of this research are to develop criteria for reviewing acceptability of the adequacy of the result of Preliminary and Detailed Investigations submitted by the implementor, and to establish a basic policy to secure safety for safety review. In FY 2010, 13 geology/climate related events for development of acceptance criteria for reviewing the adequacy of the result of Preliminary and Detailed Investigations were extracted. And the accuracy of geophysical exploration methods necessary for the Preliminary Investigation was evaluated. Regarding the research for safety review, we developed an idea of safety concept of Japanese geological disposal, and analyzed basic safety functions to secure safety. In order to verify the groundwater flow evaluation methods developed in regulatory research, the hydrological and geochemical data at Horonobe, northern Hokkaido were obtained, and simulated result of regional groundwater flow were compared with measured data. And we developed the safety scenario of geology/climate related events categorized by geological and geomorphological properties. Also we created a system to check the quality of research results in Japan and other countries in order to utilize for safety regulation, and developed a database system to compile them. (author)

Public perceptions of geology

Science.gov (United States)

Gibson, Hazel; Stewart, Iain; Anderson, Mark; Pahl, Sabine; Stokes, Alison

2014-05-01

Geological issues are increasingly intruding on the everyday lives of ordinary people. Whether it be onshore exploration and extraction of oil and gas, deep injection of water for geothermal power or underground storage of carbon dioxide and radioactive waste, many communities across Europe are being faced with potentially contested geological activity under their backyard. As well as being able to communicate the technical aspects of such work, geoscience professionals also need to appreciate that for most people the subsurface is an unfamiliar realm. In order to engage communities and individuals in effective dialogue about geological activities, an appreciation of what 'the public' already know and what they want to know is needed, but this is a subject that is in its infancy. In an attempt to provide insight into these key issues, this study examines the concerns the public have, relating to geology, by constructing 'Mental Models' of people's perceptions of the subsurface. General recommendations for public engagement strategies will be presented based on the results of selected case studies; specifically expert and non-expert mental models for communities in the south-west of England.

Geological Changes of the Americas and their Influence on the Diversification of the Neotropical Kissing Bugs (Hemiptera: Reduviidae: Triatominae).

Science.gov (United States)

Justi, Silvia A; Galvão, Cleber; Schrago, Carlos G

2016-04-01

The family Reduviidae (Hemiptera: Heteroptera), or assassin bugs, is among the most diverse families of the true bugs, with more than 6,000 species. The subfamily Triatominae (kissing bugs) is noteworthy not simply because it is the only subfamily of the Reduviidae whose members feed on vertebrate blood but particularly because all 147 known members of the subfamily are potential Chagas disease vectors. Due to the epidemiological relevance of these species and the lack of an efficient treatment and vaccine for Chagas disease, it is more common to find evolutionary studies focusing on the most relevant vectors than it is to find studies aiming to understand the evolution of the group as a whole. We present the first comprehensive phylogenetic study aiming to understand the events that led to the diversification of the Triatominae. We gathered the most diverse samples of Reduviidae and Triatominae (a total of 229 Reduviidae samples, including 70 Triatominae species) and reconstructed a robust dated phylogeny with several fossil (Reduviidae and Triatominae) calibrations. Based on this information, the possible role of geological events in several of the major cladogenetic events within Triatominae was tested for the first time. We were able to not only correlate the geological changes in the Neotropics with Triatominae evolution but also add to an old discussion: Triatominae monophyly vs. paraphyly. We found that most of the diversification events observed within the Rhodniini and Triatomini tribes are closely linked to the climatic and geological changes caused by the Andean uplift in South America and that variations in sea levels in North America also played a role in the diversification of the species of Triatoma in that region.

Russian geological education in the world market (the case of Russian State Geological Prospecting University

Directory of Open Access Journals (Sweden)

Vasily Ivanovich Lisov

2016-12-01

Full Text Available Higher geological education in Russia and in MSGPI-RSGPU specific. It - engineering. The mineral deposits determine the development of the global industry and foreign trade. Growing global demand for the profession of geologists and mining engineers. Training of foreign students in Russia has its own geopolitical and economic importance. In Russia a strong resource-based economy. It attracts students from developing countries. MGRI-RSGPU is the leading universities training specialists for mining. The article presents data about the University and types of education. Shown scientific and educational problems in higher education. This article discusses the prospects for the promotion of Russian higher geological education at the world market of educational services. The increasing role of new scientific and technological achievements in mining, enhanced environmental as well as staff requirements is revealed. Given that the leading schools in the mining industry, in addition to Russia, are formed in Canada, Germany, USA, Australia, Great Britain, many developing countries rich in natural resources, have begun to form their own national centers for training in this area. Under such competitive conditions Russian geological education maintains its own niche. Recognition of this is the active participation of Russian universities in the creation and development of the World Forum of sustainable development of mineral universities (WFURS, described in the article. The main factors of competitiveness that led to leading positions of Russian State Geological Prospecting University in system of the Russian geological education are described. Particular attention is paid to the international activities of Russian higher educational institutions including Geological Prospecting University. The basic statistics (both in the context of the country, and in the field of foreign undergraduate and graduate students enrolled at this university is provided. The

Geological aspects of radioactive waste disposal

International Nuclear Information System (INIS)

Kobera, P.

1985-01-01

Geological formations suitable for burying various types of radioactive wastes are characterized applying criteria for the evaluation and selection of geological formations for building disposal sites for radioactive wastes issued in IAEA technical recommendations. They are surface disposal sites, disposal sites in medium depths and deep disposal sites. Attention is focused on geological formations usable for injecting self-hardening mixtures into cracks prepared by hydraulic decomposition and for injecting liquid radioactive wastes into permeable rocks. Briefly outlined are current trends of the disposal of radioactive wastes in Czechoslovakia and the possibilities are assessed from the geological point of view of building disposal sites for radioactive wastes on the sites of Czechoslovak nuclear power plants at Jaslovske Bohunice, Mochovce, Dukovany, Temelin, Holice (eastern Bohemia), Blahoutovice (northern Moravia) and Zehna (eastern Slovakia). It is stated that in order to design an optimal method of the burial of radioactive waste it will be necessary to improve knowledge of geological conditions in the potential disposal sites at the said nuclear plants. There is usually no detailed knowledge of geological and hydrological conditions at greater depths than 100 m. (Z.M.)

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.

Maps showing geology, oil and gas fields, and geological provinces of South America

Science.gov (United States)

Schenk, C. J.; Viger, R.J.; Anderson, C.P.

1999-01-01

This digitally compiled map includes geology, geologic provinces, and oil and gas fields of South America. The map is part of a worldwide series on CD-ROM by World Energy Project released of the U.S. Geological Survey . The goal of the project is to assess the undiscovered, technically recoverable oil and gas resources of the world and report these results by the year 2000. For data management purposes the world is divided into eight energy regions corresponding approximately to the economic regions of the world as defined by the U.S. Department of State. South America (Region 6) includes Argentina, Bolivia, Brazil, Chile, Columbia, Ecuador, Falkland Islands, French Guiana, Guyuna, Netherlands, Netherlands Antilles, Paraguay, Peru, Suriname, Trinidad and Tobago, Uruguay, and Venezuela.

Geological data integration techniques

International Nuclear Information System (INIS)

1988-09-01

The objectives of this Technical Committee are to bring together current knowledge on geological data handling and analysis technologies as developed in the mineral and petroleum industries for geological, geophysical, geochemical and remote sensing data that can be applied to uranium exploration and resource appraisal. The recommendation for work on this topic was first made at the meeting of the NEA-IAEA Joint Group of Experts on R and D in Uranium Exploration Techniques (Paris, May 1984). In their report, processing of integrated data sets was considered to be extremely important in view of the very extensive data sets built up over the recent years by large uranium reconnaissance programmes. With the development of large, multidisciplinary data sets which includes geochemical, geophysical, geological and remote sensing data, the ability of the geologist to easily interpret large volumes of information has been largely the result of developments in the field of computer science in the past decade. Advances in data management systems, image processing software, the size and speed of computer systems and significantly reduced processing costs have made large data set integration and analysis practical and affordable. The combined signatures which can be obtained from the different types of data significantly enhance the geologists ability to interpret fundamental geological properties thereby improving the chances of finding a significant ore body. This volume is the product of one of a number of activities related to uranium geology and exploration during the past few years with the intent of bringing new technologies and exploration techniques to the IAEA Member States

Provincial geology and the Industrial Revolution.

Science.gov (United States)

Veneer, Leucha

2006-06-01

In the early nineteenth century, geology was a new but rapidly growing science, in the provinces and among the gentlemen scientists of London, Oxford and Cambridge. Industry, particularly mining, often motivated local practical geologists, and the construction of canals and railways exposed the strata for all to see. The most notable of the early practical men of geology was the mineral surveyor William Smith; his geological map of England and Wales, published in 1815, was the first of its kind. He was not alone. The contributions of professional men, and the provincial societies with which they were connected, are sometimes underestimated in the history of geology.

Engineering Geological Conditions of the Ignalina NPP Region

International Nuclear Information System (INIS)

Buceviciute, S.

1996-01-01

During engineering geological mapping, the upper part (to 15-20 m depths) of the lithosphere was investigated at the Ignalina Nuclear Power Plant (INPP) for physical rock characteristics and recent exogenic geological processes and phenomena. The final result of engineering geological mapping was the division of the area into engineering geological regions. In this case five engineering geological regions have been distinguished. The Fig. shows a scheme of engineering geological regionalization of the area and the typical sections of the engineering geological regions. The sections show genesis, age, soil type, thickness of stratigraphic genetical complex for the rocks occurring in the zone of active effect of engineering buildings, as well as the conical strength and density of the distinguished soils. 1 fig., 1 tab

Integrated path towards geological storage

International Nuclear Information System (INIS)

Bouchard, R.; Delaytermoz, A.

2004-01-01

Among solutions to contribute to CO 2 emissions mitigation, sequestration is a promising path that presents the main advantage of being able to cope with the large volume at stake when considering the growing energy demand. Of particular importance, geological storage has widely been seen as an effective solution for large CO 2 sources like power plants or refineries. Many R and D projects have been initiated, whereby research institutes, government agencies and end-users achieve an effective collaboration. So far, progress has been made towards reinjection of CO 2 , in understanding and then predicting the phenomenon and fluid dynamics inside the geological target, while monitoring the expansion of the CO 2 bubble in the case of demonstration projects. A question arises however when talking about sequestration, namely the time scale to be taken into account. Time is indeed of the essence, and points out the need to understand leakage as well as trapping mechanisms. It is therefore of prime importance to be able to predict the fate of the injected fluids, in an accurate manner and over a relevant period of time. On the grounds of geology, four items are involved in geological storage reliability: the matrix itself, which is the recipient of the injected fluids; the seal, that is the mechanistic trap preventing the injected fluids to flow upward and escape; the lower part of the concerned structure, usually an aquifer, that can be a migration way for dissolved fluids; and the man- made injecting hole, the well, whose characteristics should be as good as the geological formation itself. These issues call for specific competencies such as reservoir engineering, geology and hydrodynamics, mineral chemistry, geomechanics, and well engineering. These competencies, even if put to use to a large extent in the oil industry, have never been connected with the reliability of geological storage as ultimate goal. This paper aims at providing an introduction to these

Charnockitic ortho gneisses and mafic granulites of Cerro Olivo complex, proterozoic basement of SE Uruguay, Part 1: Geology

International Nuclear Information System (INIS)

Masquelin, H.

2008-01-01

Charnockitic ortho gneisses and mafic granulite s exposed in the Cerro Bori Block, in the center of Punta del Este terrain, were the first document occurrence of granulitic rocks from SE sector of the Uruguayan Shield. We present here their main geological features, with the purpose to suggest some petrologic and structural interesting problems for a future lithogeochemical, mineral chemistry, stable isotopes and fluid inclusion studies about these rocks. We propose some speculation form field-based studies considering a cognate magmatic origin of both kinds of rocks, previous to a homogeneous granulitic metamorphism. Some structural evidences indicate that after their uplift, these rocks were located on over thickened crust, at great to medium deepness. A cataclasis during anatexis and amphibolite-facies mineral association stabilization are common phenomena. Other evidences suggest a polycyclic character for the regional geologic evolution

Postclosure safety assessment of a deep geological repository for Canada's used nuclear fuel

Energy Technology Data Exchange (ETDEWEB)

Hunt, N.G.; Kremer, E.P.; Garisto, F.; Gierszewski, P.; Gobien, M.; Medri, C.L.D. [Nuclear Waste Management Organization, Toronto, ON (Canada); Avis, J.D. [Geofirma Engineering Ltd., Ottawa, ON (Canada); Chshyolkova, T.; Kitson, C.I.; Melnyk, W.; Wojciechowski, L.C. [Atomic Energy of Canada Limited, Pinawa, MB (Canada)

2011-07-01

This paper reports on elements of a postclosure safety assessment performed for a conceptual design and hypothetical site for a deep geological repository for Canada's used nuclear fuel. Key features are the assumption of a copper used fuel container with a steel inner vessel, container placement in vertical in-floor boreholes, a repository depth of 500 m, and a sparsely fractured crystalline rock geosphere. The study considers a Normal Evolution Scenario together with a series of Disruptive Event Scenarios. The Normal Evolution Scenario is a reasonable extrapolation of present day site features and receptor lifestyles, while the Disruptive Event Scenarios examine abnormal and unlikely failures of the containment and isolation systems. Both deterministic and probabilistic simulations were performed. The results show the peak dose consequences occur far in the future and are well below the applicable regulatory acceptance criteria and the natural background levels. (author)

Geological Corrections in Gravimetry

Science.gov (United States)

Mikuška, J.; Marušiak, I.

2015-12-01

Applying corrections for the known geology to gravity data can be traced back into the first quarter of the 20th century. Later on, mostly in areas with sedimentary cover, at local and regional scales, the correction known as gravity stripping has been in use since the mid 1960s, provided that there was enough geological information. Stripping at regional to global scales became possible after releasing the CRUST 2.0 and later CRUST 1.0 models in the years 2000 and 2013, respectively. Especially the later model provides quite a new view on the relevant geometries and on the topographic and crustal densities as well as on the crust/mantle density contrast. Thus, the isostatic corrections, which have been often used in the past, can now be replaced by procedures working with an independent information interpreted primarily from seismic studies. We have developed software for performing geological corrections in space domain, based on a-priori geometry and density grids which can be of either rectangular or spherical/ellipsoidal types with cells of the shapes of rectangles, tesseroids or triangles. It enables us to calculate the required gravitational effects not only in the form of surface maps or profiles but, for instance, also along vertical lines, which can shed some additional light on the nature of the geological correction. The software can work at a variety of scales and considers the input information to an optional distance from the calculation point up to the antipodes. Our main objective is to treat geological correction as an alternative to accounting for the topography with varying densities since the bottoms of the topographic masses, namely the geoid or ellipsoid, generally do not represent geological boundaries. As well we would like to call attention to the possible distortions of the corrected gravity anomalies. This work was supported by the Slovak Research and Development Agency under the contract APVV-0827-12.

Geology Before Pluto: Pre-encounter Considerations

Science.gov (United States)

Moore, J. M.

2014-12-01

Pluto, its large satellite Charon, and its four small known satellites represent the first trans-Neptunian Kuiper Belt objects populating the outer-most solar system beyond the gas giant planets to be studied in detail from a spacecraft (New Horizons). A complete picture of the solar nebula and solar system formation cannot be confidently formulated until representatives of this group of bodies at the edge of solar space have been examined. The Pluto system is composed of unique, lunar- and intermediate-sized objects that can tell us much about how objects with volatile icy compositions evolve. Modeling of the interior suggests that geologic activity may have been significant to some degree, and observations of frost on the surface could imply the need for a geologic reservoir for the replenishment of these phases. However, these putative indicators of Pluto's geologic history are inconclusive and unspecific. Detailed examination of Pluto's geologic record is the only plausible means of bridging the gap between theory and observation. In this talk I will examine the potential importance of these tentative indications of geologic activity and how specific spacecraft observations have been designed and used to constrain the Pluto system's geologic history. The cameras of New Horizons will provide robust data sets that should be immanently amenable to geological analysis of the Pluto system's landscapes. In this talk, we begin with a brief discussion of the planned observations by the New Horizons cameras that will bear most directly on geological interpretability. Then I will broadly review major geological processes that could potentially operate on the surfaces of Pluto and its moons. I will first survey exogenic processes (i.e., those for which energy for surface modification is supplied externally to the planetary surface): impact cratering, sedimentary processes (including volatile migration), and the work of wind. I will conclude with an assessment of the

Geology Before Pluto: Pre-Encounter Considerations

Science.gov (United States)

Moore, Jeffrey M.

2014-01-01

Pluto, its large satellite Charon, and its four known satellites represent the first trans-Neptunian Kuiper Belt objects populating the outer-most solar system beyond the gas giant planets to be studied in detail from a spacecraft (New Horizons). A complete picture of the solar nebula, and solar system formation cannot be confidently formulated until representatives of this group of bodies at the edge of solar space have been examined. The Pluto system is composed of unique lunar- and intermediate-sized objects that can tell us much about how objects with volatile icy compositions evolve. Modeling of the interior suggests that geologic activity may have been to some degree, and observations of frost on the surface could imply the need for a geologic reservoir for the replenishment of these phases. However, the putative indicators of Pluto's geologic history are inconclusive and unspecific. Detailed examination of Pluto's geologic record is the only plausible means of bridging the gap between theory and observations. In this talk I will examine the potential importance of these tentative indications of geologic activity and how specific spacecraft observations have been designed and used to constrain the Pluto system's geologic history. The cameras of New Horizons will provide robust data sets that should be immanently amenable to geological analysis of the Pluto System's landscapes. In this talk, we begin with a brief discussion of the planned observations by New Horizons' cameras that will bear most directly on geological interpretability. Then I will broadly review major geological processes that could potentially operate of the surfaces of Pluto and its moons. I will first survey exogenic processes (i.e., those for which energy for surface modification is supplied externally to the planetary surface): impact cratering, sedimentary processes (including volatile migration) and the work of wind. I will conclude with an assessment of prospects for endogenic activity

Long-term evolution of radio-active waste storage in geological formations: analogy with the weathering of mineral deposits

International Nuclear Information System (INIS)

Cantinolle, P.; Griffault, L.; Jebrak, M.

1986-01-01

The aim of this study was to select examples of mineral deposits and their weathering environment, showing the long-term behaviour, in geological time, measuring (area, volume) some constituent elements of radio-active waste storage subject to the hazards of hydrogeochemical weathering. Initially, a feasibility study was made to collate data available within the BRGM (mining group and public service) and from literature dealing with weathering of deposits. It was thus discovered that the analogy between radio-active waste storage and mineral deposits could be approached in two different yet complementary ways: - one approach is to observe the behaviour of a mineral deposit in relation to the country rocks. For this a bibliographic metallogenic study was made. The other approach is to observe the behaviour of chemical elements during deposition of a mineral deposit whose genesis is similar to the spatial and thermal environment of a deposit of radio-active waste in a geological formation. For this two sites were selected corresponding to hydrothermal systems showing strong analogies to those expected in the neighbourhood of the storage sites. These two sites, Langenberg in the Vosges and La Telhaie in Brittany, were the subject of complementary analytical work [fr

A Geospatial Information Grid Framework for Geological Survey

OpenAIRE

Wu, Liang; Xue, Lei; Li, Chaoling; Lv, Xia; Chen, Zhanlong; Guo, Mingqiang; Xie, Zhong

2015-01-01

The use of digital information in geological fields is becoming very important. Thus, informatization in geological surveys should not stagnate as a result of the level of data accumulation. The integration and sharing of distributed, multi-source, heterogeneous geological information is an open problem in geological domains. Applications and services use geological spatial data with many features, including being cross-region and cross-domain and requiring real-time updating. As a result of ...

Geological disposal system development

Energy Technology Data Exchange (ETDEWEB)

Kang, Chul Hyung; Kuh, J. E.; Kim, S. K. and others

2000-04-01

Spent fuel inventories to be disposed of finally and design base spent fuel were determined. Technical and safety criteria for a geological repository system in Korea were established. Based on the properties of spent PWR and CANDU fuels, seven repository alternatives were developed and the most promising repository option was selected by the pair-wise comparison method from the technology point of view. With this option preliminary conceptual design studies were carried out. Several module, e.g., gap module, congruent release module were developed for the overall assessment code MASCOT-K. The prominent overseas databases such as OECD/NEA FEP list were are fully reviewed and then screened to identify the feasible ones to reflect the Korean geo-hydrological conditions. In addition to this the well known scenario development methods such as PID, RES were reviewed. To confirm the radiological safety of the proposed KAERI repository concept the preliminary PA was pursued. Thermo-hydro-mechanical analysis for the near field of repository were performed to verify thermal and mechanical stability for KAERI repository system. The requirements of buffer material were analyzed, and based on the results, the quantitative functional criteria for buffer material were established. The hydraulic and swelling property, mechanical properties, and thermal conductivity, the organic carbon content, and the evolution of pore water chemistry were investigated. Based on the results, the candidate buffer material was selected.

Geological disposal system development

International Nuclear Information System (INIS)

Kang, Chul Hyung; Kuh, J. E.; Kim, S. K. and others

2000-04-01

Spent fuel inventories to be disposed of finally and design base spent fuel were determined. Technical and safety criteria for a geological repository system in Korea were established. Based on the properties of spent PWR and CANDU fuels, seven repository alternatives were developed and the most promising repository option was selected by the pair-wise comparison method from the technology point of view. With this option preliminary conceptual design studies were carried out. Several module, e.g., gap module, congruent release module were developed for the overall assessment code MASCOT-K. The prominent overseas databases such as OECD/NEA FEP list were are fully reviewed and then screened to identify the feasible ones to reflect the Korean geo-hydrological conditions. In addition to this the well known scenario development methods such as PID, RES were reviewed. To confirm the radiological safety of the proposed KAERI repository concept the preliminary PA was pursued. Thermo-hydro-mechanical analysis for the near field of repository were performed to verify thermal and mechanical stability for KAERI repository system. The requirements of buffer material were analyzed, and based on the results, the quantitative functional criteria for buffer material were established. The hydraulic and swelling property, mechanical properties, and thermal conductivity, the organic carbon content, and the evolution of pore water chemistry were investigated. Based on the results, the candidate buffer material was selected

Evolution of pyrochlore composition in a carbonatite complex of the Eastern European platform

International Nuclear Information System (INIS)

Nechelyastnov, G.N.; Pozharitskaya, L.K.

1986-01-01

X-ray microanalysis is used to study 29 pyrochlore group mineral samples of the East European platform carbonatite complex. Pyrochlore sequential evolution: frm high in tantalum and uranium, passing uranium poor in tantalum to low in tantalum and uranium and also an increased content of iron, manganese, magnesium and lead, is shown. Calcium, niobium, tantalum non-homogeneous distribution in pyrochlore grains is detected. Peculiarities of pyrochlore group mineral composition reflect the effect of specific geologic-structural position of the East European platform carbonatites high depth of formation and intensive development of deformations) on general evolution for pyrochlore of carbonatite complexes and related to it pyrochlore specific nature, in particular, high uranium and low niobium contents

County digital geologic mapping. Final report

Energy Technology Data Exchange (ETDEWEB)

Hess, R.H.; Johnson, G.L.; dePolo, C.M.

1995-12-31

The purpose of this project is to create quality-county wide digital 1:250,000-scale geologic maps from existing published 1:250,000-scale Geologic and Mineral Resource Bulletins published by the Nevada Bureau of Mines and Geology (NBMG). An additional data set, based on current NBMG research, Major and Significant Quaternary and Suspected Quaternary Faults of Nevada, at 1:250,000 scale has also been included.

County digital geologic mapping. Final report

International Nuclear Information System (INIS)

Hess, R.H.; Johnson, G.L.; dePolo, C.M.

1995-01-01

The purpose of this project is to create quality-county wide digital 1:250,000-scale geologic maps from existing published 1:250,000-scale Geologic and Mineral Resource Bulletins published by the Nevada Bureau of Mines and Geology (NBMG). An additional data set, based on current NBMG research, Major and Significant Quaternary and Suspected Quaternary Faults of Nevada, at 1:250,000 scale has also been included

The Formation and Evolution of Tessera and Insights into the Beginning of Recorded History on Venus: Geology of the Fortuna Tessera Quadrangle (V-2)

Science.gov (United States)

Head, J. W.; Ivanov, M. A.

2010-01-01

Today, and throughout its recorded history, Venus can be classified as a "one-plate planet." The observable geological record of the planet comprises only the last 1/4 or less of its overall geologic history. As shown by many authors, it started with intensive deformation in broad regions to form tessera [1-6] during the Fortunian period of history [7]. The period of tessera formation quickly changed to numerous zonal deformational belts of ridges and grooves that were followed by emplacement of vast volcanic plains (shield plains, regional plains) [7,8]. During the final epoch of the geologic history of Venus, large but isolated centers of volcanism formed extensive fields of lavas, with tectonics concentrated within fewer very prominent rift zones [8,9]. The observable changes in intensity and character of volcanism and tectonics suggest progressive changes from thin lithosphere early in the geologic history to thick lithosphere during later epochs [6,10]. We have little idea of the character of the first 3/4 of Venus' history. So, what does the earliest period of recorded history tell us about the transition from the Pre-Fortunian to the Fortunian period and what insight does this give us into this earlier period?

Continental crust formation: Numerical modelling of chemical evolution and geological implications

Science.gov (United States)

Walzer, U.; Hendel, R.

2017-05-01

Oceanic plateaus develop by decompression melting of mantle plumes and have contributed to the growth of the continental crust throughout Earth's evolution. Occasional large-scale partial melting events of parts of the asthenosphere during the Archean produced large domains of precursor crustal material. The fractionation of arc-related crust during the Proterozoic and Phanerozoic contributed to the growth of continental crust. However, it remains unclear whether the continents or their precursors formed during episodic events or whether the gaps in zircon age records are a function of varying preservation potential. This study demonstrates that the formation of the continental crust was intrinsically tied to the thermoconvective evolution of the Earth's mantle. Our numerical solutions for the full set of physical balance equations of convection in a spherical shell mantle, combined with simplified equations of chemical continent-mantle differentiation, demonstrate that the actual rate of continental growth is not uniform through time. The kinetic energy of solid-state mantle creep (Ekin) slowly decreases with superposed episodic but not periodic maxima. In addition, laterally averaged surface heat flow (qob) behaves similarly but shows peaks that lag by 15-30 Ma compared with the Ekin peaks. Peak values of continental growth are delayed by 75-100 Ma relative to the qob maxima. The calculated present-day qob and total continental mass values agree well with observed values. Each episode of continental growth is separated from the next by an interval of quiescence that is not the result of variations in mantle creep velocity but instead reflects the fact that the peridotite solidus is not only a function of pressure but also of local water abundance. A period of differentiation results in a reduction in regional water concentrations, thereby increasing the temperature of the peridotite solidus and the regional viscosity of the mantle. By plausibly varying the

Geologic Resource Evaluation of Pu'ukohola Heiau National Historic Site, Hawai'i: Part I, Geology and Coastal Landforms

Science.gov (United States)

Richmond, Bruce M.; Cochran, Susan A.; Gibbs, Ann E.

2008-01-01

Geologic resource inventories of lands managed by the National Park Service (NPS) are important products for the parks and are designed to provide scientific information to better manage park resources. Park-specific geologic reports are used to identify geologic features and processes that are relevant to park ecosystems, evaluate the impact of human activities on geologic features and processes, identify geologic research and monitoring needs, and enhance opportunities for education and interpretation. These geologic reports are planned to provide a brief geologic history of the park and address specific geologic issues forming a link between the park geology and the resource manager. The Kona coast National Parks of the Island of Hawai'i are intended to preserve the natural beauty of the Kona coast and protect significant ancient structures and artifacts of the native Hawaiians. Pu'ukohola Heiau National Historic Site (PUHE), Kaloko-Honokohau National Historical Park (KAHO), and Pu'uhonua O Honaunau National Historical Park (PUHO) are three Kona parks studied by the U.S. Geological Survey (USGS) Coastal and Marine Geology Team in cooperation with the National Park Service. This report is one of six related reports designed to provide geologic and benthic-habitat information for the three Kona parks. Each geology and coastal-landform report describes the regional geologic setting of the Hawaiian Islands, gives a general description of the geology of the Kona coast, and presents the geologic setting and issues for one of the parks. The related benthic-habitat mapping reports discuss the marine data and habitat classification scheme, and present results of the mapping program. Pu'ukohola Heiau National Historic Site (PUHE) is the smallest (~86 acres) of three National Parks located on the leeward Kona coast of the Island of Hawai'i. The main structure at PUHE, Pu'ukohola Heiau, is an important historical temple that was built during 1790-91 by King Kamehameha I

Natural selection drives the evolution of ant life cycles.

Science.gov (United States)

Wilson, Edward O; Nowak, Martin A

2014-09-02

The genetic origin of advanced social organization has long been one of the outstanding problems of evolutionary biology. Here we present an analysis of the major steps in ant evolution, based for the first time, to our knowledge, on combined recent advances in paleontology, phylogeny, and the study of contemporary life histories. We provide evidence of the causal forces of natural selection shaping several key phenomena: (i) the relative lateness and rarity in geological time of the emergence of eusociality in ants and other animal phylads; (ii) the prevalence of monogamy at the time of evolutionary origin; and (iii) the female-biased sex allocation observed in many ant species. We argue that a clear understanding of the evolution of social insects can emerge if, in addition to relatedness-based arguments, we take into account key factors of natural history and study how natural selection acts on alleles that modify social behavior.

Gan-Hang tectonic belt and its geologic significance

International Nuclear Information System (INIS)

Deng Jiarui; Zhang Zhiping.

1989-01-01

Gan-Hang tectonic belt is predominantly controlled by Gan-Hang fracture zone. It is mainly composed of Yongfeng-Zhuji downwarping zone, Gan-Hang volcanic activity structural belt and Gan-Hang red basin downfaulted zone. Gan-Hang fracture zone is derived from evolution and development of Shaoxing-Jiangshan deep fracture. It is mainly composed of three deep and large fracture and Fuzhou-Yongfeng large fracture. The fracture zone is a long active belt, but in each active period the geologic structural patterns intensity, depth and forming time were not same. Gan-Hang tectonic belt possesses obvious inheritance. It has always maintained the character of the relative depression or low land since the Caledonian movement. This specific structural environment is favourable for uranium mineralization. At any rate, the formation of this uranium minerogenetic zone has been experiencing a long and complicated processes which were closely associated with long activity of Gan-Hang fracture zone

A petrological study of Paleoarchean rocks of the Onverwacht Group: New insights into the geologic evolution of the Barberton Greenstone Belt, South Africa

Science.gov (United States)

Grosch, E. G.; Mcloughlin, N.; Abu-Alam, T. S.; Vidal, O.

2012-12-01

This study presents a multi-disciplinary petrological approach applied to surface samples and a total of 800 m of scientific drill core that furthers our understanding of the geologic evolution of the ca. 3.5 to 3.2 Ga Onverwacht Group of the Barberton greenstone belt (BGB), South Africa. Detrital zircon grains in coarse (diamictite) to fine-grained clastic sedimentary rocks of the Noisy formation (drill core KD2a) that unconformably overlies the volcanic ca. 3472 Ma Hooggenoeg Formation, are investigated by laser ablation LA-ICP-MS to constrain their 207Pb/206Pb ages for depositional age and provenance. A wide range in 207Pb/206Pb ages between ca. 3600 and 3430 Ma is reported, corresponding to surrounding TTG plutons and the ca.3667-3223 Ma Ancient Gneiss Complex. The youngest detrital zircon grain identified has an age of 3432 ± 10 Ma. Given the short time interval for a major change in geologic environment between ca. 3472 Ma and ca. 3432 Ma, it is argued here, that the Noisy formation is the earliest tectonic basin in the BGB, which developed during major tectonic uplift at ca. 3432 Ma. In the overlying ca. 3334 Ma Kromberg type-section, application of a chlorite thermodynamic multi-equilibrium calculation, dioctahedral mica hydration-temperature curve and pseudosection modelling, indicates a wide range in metamorphic conditions from sub-greenschist to the uppermost greenschist facies across the Kromberg type-section. A central mylonitic fuchsite-bearing zone, referred to as the Kromberg Section Mylonites, records at least two metamorphic events: a high-T, low-P (420 ± 30oC, sedimentary sequence contains detrital and diagenetic pyrites with a significant variation in Δ33S of -0.62 to +1.4‰ and δ34SCDT between -7.00 and +12.6‰ in the upper turbidite unit, to more narrow isotopic ranges with magmatic-atmospheric values in the underlying polymictitic diamictite. A sedimentary quartz-pyrite vein in the diamictite records the largest range and most negative

On the Geologic Time Scale

NARCIS (Netherlands)

Gradstein, F.M.; Ogg, J.G.; Hilgen, F.J.

2012-01-01

This report summarizes the international divisions and ages in the Geologic Time Scale, published in 2012 (GTS2012). Since 2004, when GTS2004 was detailed, major developments have taken place that directly bear and have considerable impact on the intricate science of geologic time scaling. Precam

Geology of the Huntsville quadrangle, Alabama

Science.gov (United States)

Sanford, T.H.; Malmberg, G.T.; West, L.R.

1961-01-01

The 7 1/2-minute Huntsville quadrangle is in south-central Madison County, Ala., and includes part of the city of Hunstville. The south, north, east, and west boundaries of the quadrangle are about 3 miles north of the Tennessee River, 15 1/2 miles south of the Tennessee line, 8 miles west of the Jackson County line, and 9 miles east of the Limestone County line. The bedrock geology of the Huntsville quadrangle was mapped by the U.S. Geological Survey in cooperation with the city of Hunstville and the Geological Survey of Alabama as part of a detailed study of the geology and ground-water resources of Madison County, with special reference to the Huntsville area. G. T. Malmberg began the geologic mapping of the county in July 1953, and completed it in April 1954. T. H. Sanford, Jr., assisted Malmberg in the final phases of the county mapping, which included measuring geologic sections with hand level and steel tape. In November 1958 Sanford, assisted by L. R. West, checked contacts and elevations in the Hunstville quadrangle; made revisions in the contact lines; and wrote the text for this report. The fieldwork for this report was completed in April 1959.

Tracking natural and anthropogenic Pb exposure to its geological source.

Science.gov (United States)

Evans, Jane; Pashley, Vanessa; Madgwick, Richard; Neil, Samantha; Chenery, Carolyn

2018-01-31

Human Pb exposure comes from two sources: (i) natural uptake through ingestion of soils and typified by populations that predate mining activity and (ii) anthropogenic exposure caused by the exposure to Pb derived from ore deposits. Currently, the measured concentration of Pb within a sample is used to discriminate between these two exposure routes, with the upper limit for natural exposure in skeletal studies given as 0.5 or 0.7 mg/kg in enamel and 0.5/0.7 μg/dL in blood. This threshold approach to categorising Pb exposure does not distinguish between the geological origins of the exposure types. However, Pb isotopes potentially provide a more definitive means of discriminating between sources. Whereas Pb from soil displays a crustal average 238 U/ 204 Pb (μ) value of c 9.7, Pb from ore displays a much wider range of evolution pathways. These characteristics are transferred into tooth enamel, making it possible to characterize human Pb exposure in terms of the primary source of ingested Pb and to relate mining activity to geotectonic domains. We surmise that this ability to discriminate between silicate and sulphide Pb exposure will lead to a better understanding of the evolution of early human mining activity and development of exposure models through the Anthropocene.

Geological disposal: security and R and D. Security of 'second draft for R and D of geological disposal'

International Nuclear Information System (INIS)

Shiotsuki, Masao; Miyahara, Kaname

2003-01-01

The second draft for R and D of geological disposal (second draft) was arranged in 1999. The idea of security of geological disposal in the second draft is explained. The evaluation results of the uncertainty analysis and an example of evaluation of the effect of separation nuclear transmutation on the geological disposal are shown. The construction of strong engineered barrier is a basic idea of geological disposal system. Three processes such as isolation, engineering countermeasures and safety evaluation are carried out for the security of geological disposal. The security of geological environment for a long time of 12 sites in Japan was studied by data. Provability of production and enforcement of engineered barrier were confirmed by trial of over pack, tests and the present and future technologies developed. By using the conditions of reference case in the second draft, the evaluation results of dose effects in the two cases: 1) 90 to 99% Cs and Sr removed from HLW (High Level radioactive Waste) and 2) high stripping ratio of actinium series are explained. (S.Y.)

Aniakchak National Monument and Preserve: Geologic resources inventory report

Science.gov (United States)

Hults, Chad P.; Neal, Christina

2015-01-01

This GRI report is a companion document to previously completed GRI digital geologic map data. It was written for resource managers to support science-informed decision making. It may also be useful for interpretation. The report was prepared using available geologic information, and the NPS Geologic Resources Division conducted no new fieldwork in association with its preparation. Sections of the report discuss distinctive geologic features and processes within the park, highlight geologic issues facing resource managers, describe the geologic history leading to the present-day landscape, and provide information about the GRI geologic map data. A poster illustrates these data. The Map Unit Properties Table summarizes report content for each geologic map unit.

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 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.

Review on influences of colloids on geologic disposal of high level radioactive waste. For better understanding of natural colloidal materials

International Nuclear Information System (INIS)

Kanai, Yutaka; Suzuki, Masaya; Kamioka, Hikari; Yoshida, Takahiro; Suko, Takeshi

2007-01-01

Although the influences of colloidal materials on radionuclide transport in geological media are pointed out, their behaviors in natural environment have not yet been well elucidated and therefore their influences on the geologic disposal of high-level radioactive waste (HLW) are not fully estimated quantitatively. This paper reviewed the studies on natural colloids, especially focused on inorganic, organic and biological colloids, and discussed the future works to be carried out. Much attention should be paid to the sampling and analysis. Excellent techniques for in-situ observation, concentration without changing the state of colloid, standard procedure for analysis, are necessary to be developed. More research studies on the behaviors of colloids are required in not only far- and near-fields but also items on effects of the environments and its evolution. (author)

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 and Chemical Factors that Impacted the Biological Utilization of Cobalt in the Archean Eon

Science.gov (United States)

Moore, Eli K.; Hao, Jihua; Prabhu, Anirudh; Zhong, Hao; Jelen, Ben I.; Meyer, Mike; Hazen, Robert M.; Falkowski, Paul G.

2018-03-01

The geosphere and biosphere coevolved and influenced Earth's biological and mineralogical diversity. Changing redox conditions influenced the availability of different transition metals, which are essential components in the active sites of oxidoreductases, proteins that catalyze electron transfer reactions across the tree of life. Despite its relatively low abundance in the environment, cobalt (Co) is a unique metal in biology due to its importance to a wide range of organisms as the metal center of vitamin B12 (aka cobalamin, Cbl). Cbl is vital to multiple methyltransferase enzymes involved in energetically favorable metabolic pathways. It is unclear how Co availability is linked to mineral evolution and weathering processes. Here we examine important biological functions of Co, as well as chemical and geological factors that may have influenced the utilization of Co early in the evolution of life. Only 66 natural minerals are known to contain Co as an essential element. However, Co is incorporated as a minor element in abundant rock-forming minerals, potentially representing a reliable source of Co as a trace element in marine systems due to weathering processes. We developed a mineral weathering model that indicates that dissolved Co was potentially more bioavailable in the Archean ocean under low S conditions than it is today. Mineral weathering, redox chemistry, Co complexation with nitrogen-containing organics, and hydrothermal environments were crucial in the incorporation of Co in primitive metabolic pathways. These chemical and geological characteristics of Co can inform the biological utilization of other trace metals in early forms of life.

Complex geologic characterization of the repository environment

Energy Technology Data Exchange (ETDEWEB)

Harper, T R [British Petroleum Research Center, Sunberry, England; Szymanski, J S

1982-01-01

The present basis for characterizing geological environments is identified in this paper, and the additional requirements imposed by the need to isolate high-level waste safely are discussed. Solutions to these additional requirements are proposed. The time scale of concern and the apparent complexity of the required multidisciplinary approach are identified. It is proposed that an increased use of the geologic record, together with a recognition that all geologic processes operate within an interdependent system, be a key feature in geologic characterization of deep repositories.

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)

A preliminary study on the geochemical environment for deep geological disposal of high level radioactive waste in Korea

International Nuclear Information System (INIS)

Kim, Chun Soo; Bae, Dae Seok; Kim, Kyung Su; Koh, Yong Kwon; Park, Byoung Yun

2000-03-01

Geochemical study on the groundwater from crystalline rocks (granite and gneiss) for the deep geological disposal of high-level radioactive waste was carried out in order to elucidate the hydrogeochemical and isotope characteristics and geochemical evolution of the groundwater. Study areas are Jungwon, Chojeong, Youngcheon and Yusung for granite region, Cheongyang for gneiss region, and Yeosu for volcanic region. Groundwaters of each study areas weree sampled and analysed systematically. Groundwaters can be grouped by their chemistry and host rock. Origin of the groundwater was proposed by isotope ( 18 O, 2 H, 13 C, 34 S, 87 Sr, 15 N) studies and the age of groundwater was inferred from their tritium contents. Based ont the geochemical and isotope characteristics, the geochemical evolutions of each types of groundwater were simulated using SOLVEQ/CHILLER and PHREEQC programs

Description of geological data in SKBs database GEOTAB

International Nuclear Information System (INIS)

Stark, T.

1988-01-01

Measurements for the characterization of geological, geophysical, hydrogeological and hydrochemical condition have been performed since 1977 in specific site investigation as well as for geoscientific projects. The database comprises four main groups of data volumes. These are: geological data, geophysical data, hydrogeological data, and hydrochemical data. In the database, background information from the investigations and results are stored on-line on the VAX 750, while raw data are either stored on-line or on magnetic tapes. This report deals with geological data and describes the dataflow from the measurements at the sites to the result tables in the database. All of the geological investigations were carried out by the Swedish Geological Survey, and since July 1982 by Swedish Geological Co, SGAB. The geological investigations have been divided into three categories, and each category is stored separately in the database. The are: surface factures, core mapping, and chemical analyses. At SGU/SGAB the geological data were stored on-line on-line on a PRIME 750 mini computer, on microcomputer floppy disks or in filed paper protocols. During 1987 the data files were transferred from SGAB to datafiles on the VAX computer. In the report the data flow of each of the three geological information categories are described separately. (L.E.)

USGS National Geologic Map Database Collection

Data.gov (United States)

U.S. Geological Survey, Department of the Interior — The National Geologic Map Database (NGMDB) is a Congressionally mandated national archive of geoscience maps, reports, and stratigraphic information. According to...

Age determination and geological studies

International Nuclear Information System (INIS)

Stevens, R.D.; Delabio, R.N.; Lachance, G.R.

1982-01-01

Two hundred and eight potassium-argon age determinations carried out on Canadian rocks and minerals are reported. Each age determination is accompanied by a description of the rock and mineral concentrate used; brief interpretative comments regarding the geological significance of each age are also provided where possible. The experimental procedures employed are described in brief outline and the constants used in the calculation of ages are listed. Two geological time-scales are reproduced in tabular form for ready reference and an index of all Geological Survey of Canada K-Ar age determinations published in this format has been prepared using NTS quadrangles as the primary reference

The speleothem record from Sicily, an important palaeoclimate testimony in the heart of the Mediterranean: overview of current research

Science.gov (United States)

Deininger, Michael; Vattano, Marco; McDermott, Frank; Frisia, Silvia; Borsato, Andrea; Frank, Norbert; Spötl, Christoph; Scholz, Denis; Di Maggio, Cipriano; Madonia, Giuliana

2017-04-01

Sicily is located in the heart of the Mediterranean and takes a strategic position between the western and eastern Mediterranean as well as between northern Africa and continental Europe. It is a place of a diverse and great cultural heritage that goes back many thousands of years; it had been colonised by Phoenicians, Carthaginians, Greeks and Romans in Ancient times and served as a trading post and granary - the latter particularly for the Romans. Climate change scenarios studies suggest that Mediterranean ecosystems could change into deserts as a consequence of shifting temperature and precipitation patterns unparalleled in the Holocene period (Guiot and Cramer, 2016). It is, therefore, essential to shed light on past precipitation changes to gain knowledge on the timing, dynamics and causes of these changes by making use of natural environmental archives (such as speleothems). This information is not only important for palaeoclimate data-model comparisons but can also give archaeologists a wealth of information when studying cultural transformations. Speleothems are valuable natural archives of past climatic and environmental conditions on the continents. Major strengths include their suitability for accurate U-series age determinations and their preservation of multiple quasi-independent climate proxies - that can be linked to precipitation changes. Hence, speleothems proxy time series from the Mediterranean can be regarded as an important testimony of past environmental and climate changes (including precipitation) that allow to provide answers to the aforementioned questions. Here we present first result of ongoing speleothem research on Sicily, with focuses on Pietrazzi cave (Grotta dei Pietrazzi) located west of Palermo. It developed in limestone (limestone consisting of bioclastic packstone/wackestones, fore reef coral rudstones (calcirudite) and calcarenites.) of the Calcare di Piano Battaglia Formation. Pietrazzi cave is more than 600 m in length and

Evaluation of geologic and geophysical techniques for surface-to-subsurface projections of geologic characteristics in crystalline rock

International Nuclear Information System (INIS)

1985-07-01

Granitic and gneissic rock complexes are being considered for their potential to contain and permanently isolate high-level nuclear waste in a deep geologic repository. The use of surface geologic and geophysical techniques has several advantages over drilling and testing methods for geologic site characterization in that the techniques are typically less costly, provide data over a wider area, and do not jeopardize the physical integrity of a potential repository. For this reason, an extensive literature review was conducted to identify appropriate surface geologic and geophysical techniques that can be used to characterize geologic conditions in crystalline rock at proposed repository depths of 460 to 1,220 m. Characterization parameters such as rock quality; fracture orientation, spacing; and aperture; depths to anomalies; degree of saturation; rock body dimensions; and petrology are considered to be of primary importance. Techniques reviewed include remote sensing, geologic mapping, petrographic analysis, structural analysis, gravity and magnetic methods, electrical methods, and seismic methods. Each technique was reviewed with regard to its theoretical basis and field application; geologic parameters that can be evaluated; advantages and limitations, and, where available, case history applications in crystalline rock. Available information indicates that individual techniques provide reliable information on characteristics at the surface, but have limited success in projections to depths greater that approximately 100 m. A combination of integrated techniques combines with data from a limited number of boreholes would significantly improve the reliability and confidence of early characterization studies to provide qualitative rock body characteristics for region-to-area and area-to-site selection evaluations. 458 refs., 32 figs., 14 tabs

IAEA safeguards for geological repositories

International Nuclear Information System (INIS)

Moran, B.W.

2005-01-01

In September. 1988, the IAEA held its first formal meeting on the safeguards requirements for the final disposal of spent fuel and nuclear material-bearing waste. The consensus recommendation of the 43 participants from 18 countries at this Advisory Group Meeting was that safeguards should not terminate of spent fuel even after emplacement in, and closure of, a geologic repository.' As a result of this recommendation, the IAEA initiated a series of consultants' meetings and the SAGOR Programme (Programme for the Development of Safeguards for the Final Disposal of Spent Fuel in Geologic Repositories) to develop an approach that would permit IAEA safeguards to verify the non-diversion of spent fuel from a geologic repository. At the end of this process, in December 1997, a second Advisory Group Meeting, endorsed the generic safeguards approach developed by the SAGOR Programme. Using the SAGOR Programme results and consultants' meeting recommendations, the IAEA Department of Safeguards issued a safeguards policy paper stating the requirements for IAEA safeguards at geologic repositories. Following approval of the safeguards policy and the generic safeguards approach, the Geologic Repository Safeguards Experts Group was established to make recommendations on implementing the safeguards approach. This experts' group is currently making recommendations to the IAEA regarding the safeguards activities to be conducted with respect to Finland's repository programme. (author)

Evaluating Boy Scout Geology Education, A Pilot Study

Science.gov (United States)

Hintz, R. S.; Thomson, B.

2008-12-01

This study investigated geology knowledge acquisition by Boy Scouts through use of the Boy Scout Geology Merit Handbook. In this study, boys engaged in hands-on interactive learning following the requirements set forth in the Geology Merit Badge Handbook. The purposes of this study were to determine the amount of geology content knowledge engendered in adolescent males through the use of the Geology Merit Badge Handbook published by the Boy Scouts of America; to determine if single sex, activity oriented, free-choice learning programs can be effective in promoting knowledge development in young males; and to determine if boys participating in the Scouting program believed their participation helped them succeed in school. Members of a local Boy Scout Troop between the ages of 11 and 18 were invited to participate in a Geology Merit Badge program. Boys who did not already possess the badge were allowed to self-select participation. The boys' content knowledge of geology, rocks, and minerals was pre- and post-tested. Boys were interviewed about their school and Scouting experiences; whether they believed their Scouting experiences and work in Merit Badges contributed to their success in school. Contributing educational theories included single-sex education, informal education with free-choice learning, learning styles, hands-on activities, and the social cognitive theory concept of self-efficacy. Boys who completed this study seemed to possess a greater knowledge of geology than they obtained in school. If boys who complete the Boy Scout Geology Merit Badge receive additional geological training, their field experiences and knowledge acquired through this learning experience will be beneficial, and a basis for continued scaffolding of geologic knowledge.

Fission-track ages and their geological interpretation

International Nuclear Information System (INIS)

Wagner, G.A.

1981-01-01

In fission-track dating, experimental procedures such as etching and thermal pre-treatment may strongly affect the age values determined and their geological interpretation. This peculiarity is due to the common phenomenon of partial fading of fossil (spontaneous-) fission tracks during a sample's geological history. The proper geological interpretation of the age data must take into account the specific experimental conditions, the stability characteristics and size distribution of fission tracks in the sample, the ages of co-existing minerals, and the independent information about the thermal history of the geological region. (author)

Modeling geologic storage of carbon dioxide: Comparison of non-hysteretic and hysteretic characteristic curves

International Nuclear Information System (INIS)

Doughty, Christine

2007-01-01

Numerical models of geologic storage of carbon dioxide (CO 2 ) in brine-bearing formations use characteristic curves to represent the interactions of non-wetting-phase CO 2 and wetting-phase brine. When a problem includes both injection of CO 2 (a drainage process) and its subsequent post-injection evolution (a combination of drainage and wetting), hysteretic characteristic curves are required to correctly capture the behavior of the CO 2 plume. In the hysteretic formulation, capillary pressure and relative permeability depend not only on the current grid-block saturation, but also on the history of the saturation in the grid block. For a problem that involves only drainage or only wetting, a non-hysteretic formulation, in which capillary pressure and relative permeability depend only on the current value of the grid-block saturation, is adequate. For the hysteretic formulation to be robust computationally, care must be taken to ensure the differentiability of the characteristic curves both within and beyond the turning-point saturations where transitions between branches of the curves occur. Two example problems involving geologic CO 2 storage are simulated with TOUGH2, a multiphase, multicomponent code for flow and transport through geological media. Both non-hysteretic and hysteretic formulations are used, to illustrate the applicability and limitations of non-hysteretic methods. The first application considers leakage of CO 2 from the storage formation to the ground surface, while the second examines the role of heterogeneity within the storage formation

On the Tidal Evolution of the Earth-Moon System: A Cosmological Model

Directory of Open Access Journals (Sweden)

Arbab A. I.

2009-01-01

Full Text Available We have presented a cosmological model for the tidal evolution of the Earth-Moon system. We have found that the expansion of the universe has immense consequences on our local systems. The model can be compared with the present observational data. The close approach problem inflicting the known tidal theory is averted in this model. We have also shown that the astronomical and geological changes of our local systems are of the order of Hubble constant.

International Approaches for Nuclear Waste Disposal in Geological Formations: Report on Fifth Worldwide Review

Energy Technology Data Exchange (ETDEWEB)

Faybishenko, Boris [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Birkholzer, Jens [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Persoff, Peter [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Sassani, David [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Swift, Peter [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2016-09-01

The goal of the Fifth Worldwide Review is to document evolution in the state-of-the-art of approaches for nuclear waste disposal in geological formations since the Fourth Worldwide Review that was released in 2006. The last ten years since the previous Worldwide Review has seen major developments in a number of nations throughout the world pursuing geological disposal programs, both in preparing and reviewing safety cases for the operational and long-term safety of proposed and operating repositories. The countries that are approaching implementation of geological disposal will increasingly focus on the feasibility of safely constructing and operating their repositories in short- and long terms on the basis existing regulations. The WWR-5 will also address a number of specific technical issues in safety case development along with the interplay among stakeholder concerns, technical feasibility, engineering design issues, and operational and post-closure safety. Preparation and publication of the Fifth Worldwide Review on nuclear waste disposal facilitates assessing the lessons learned and developing future cooperation between the countries. The Report provides scientific and technical experiences on preparing for and developing scientific and technical bases for nuclear waste disposal in deep geologic repositories in terms of requirements, societal expectations and the adequacy of cases for long-term repository safety. The Chapters include potential issues that may arise as repository programs mature, and identify techniques that demonstrate the safety cases and aid in promoting and gaining societal confidence. The report will also be used to exchange experience with other fields of industry and technology, in which concepts similar to the design and safety cases are applied, as well to facilitate the public perception and understanding of the safety of the disposal approaches relative to risks that may increase over long times frames in the absence of a successful

Geological evolution of the center-southern portion of the Guyana shield based on the geochemical, geochronological and isotopic studies of paleoproterozoic granitoids from southeastern Roraima, Brazil

International Nuclear Information System (INIS)

Almeida, Marcelo Esteves

2006-01-01

This study focuses the granitoids of center-southern portion of Guyana Shield, southeastern Roraima, Brazil. The region is characterized by two tectonic-stratigraphic domains, named as Central Guyana (GCD) and Uatuma-Anaua (UAD) and located probably in the limits of geochronological provinces (e.g. Ventuari-Tapajos or Tapajos-Parima, Central Amazonian and Maroni-Itacaiunas or Transamazon). The aim this doctoral thesis is to provide new petrological and lithostratigraphic constraints on the granitoid rocks and contribute to a better understanding of the origin and geo dynamic evolution of Guyana Shield. The GCD is only locally studied near to the UAD boundary, and new geological data and two single zircon Pb-evaporation ages in mylonitic biotite granodiorite (1.89 Ga) and foliated hastingsite-biotite granite (1.72 Ga) are presented. These ages of the protholiths contrast with the lithostratigraphic picture in the other areas of Cd (1.96-1.93 Ga). Regional mapping, petrography, geochemistry and zircon geochronology carried out in the Urad have showed widespread Paleoproterozoic calc-alkaline granitic magmatism. These granitoid rocks are distributed into several magmatic associations with different Paleoproterozoic (1.97-1.89 Ga) ages, structural and geochemical affinities. Detailed mapping, petrographic and geochronological studies have distinguished two main sub domains in the UAD. In the northern UAD, the high-K calc-alkaline Martins Pereira (1.97 Ga) and Serra Dourada S-type granites (1.96 Ga) are affected by NE-SW and E-W ductile dextral shear-zones, showing coexistence of magmatic and deformational fabrics related to heterogeneous deformation. Inliers of basement (2.03 Ga) crop out northeast of this area, and are formed by meta volcano-sedimentary sequence (Cauarane Group) and TTG-like calc-alkaline association (Anaua Complex). Xenoliths of meta diorites (Anaua Complex) and para gneisses (Cauarane Group) reinforce the intrusive character of Martins Pereira

Geological remote sensing

Science.gov (United States)

Bishop, Charlotte; Rivard, Benoit; de Souza Filho, Carlos; van der Meer, Freek

2018-02-01

Geology is defined as the 'study of the planet Earth - the materials of which it is made, the processes that act on these materials, the products formed, and the history of the planet and its life forms since its origin' (Bates and Jackson, 1976). Remote sensing has seen a number of variable definitions such as those by Sabins and Lillesand and Kiefer in their respective textbooks (Sabins, 1996; Lillesand and Kiefer, 2000). Floyd Sabins (Sabins, 1996) defined it as 'the science of acquiring, processing and interpreting images that record the interaction between electromagnetic energy and matter' while Lillesand and Kiefer (Lillesand and Kiefer, 2000) defined it as 'the science and art of obtaining information about an object, area, or phenomenon through the analysis of data acquired by a device that is not in contact with the object, area, or phenomenon under investigation'. Thus Geological Remote Sensing can be considered the study of, not just Earth given the breadth of work undertaken in planetary science, geological features and surfaces and their interaction with the electromagnetic spectrum using technology that is not in direct contact with the features of interest.

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

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)

Ontology-aided annotation, visualization and generalization of geological time-scale information from online geological map services

NARCIS (Netherlands)

Ma, X.; Carranza, E.J.M.; Wu, C.; Meer, F.D. van der

2012-01-01

Geological maps are increasingly published and shared online, whereas tools and services supporting information retrieval and knowledge discovery are underdeveloped. In this study, we developed an ontology of geological time scale by using a RDF (Resource Description Framework) model to represent

Ontology-aided annotation, visualization and generalization of geological time scale information from online geological map services

NARCIS (Netherlands)

Ma, Marshal; Ma, X.; Carranza, E.J.M; Wu, C.; van der Meer, F.D.

2012-01-01

Geological maps are increasingly published and shared online, whereas tools and services supporting information retrieval and knowledge discovery are underdeveloped. In this study, we developed an ontology of geological time scale by using a Resource Description Framework model to represent the

Middle proterozoic supra crustal and brazilian orogeny in the southeast Ceara state: a mono cyclic evolution

International Nuclear Information System (INIS)

Sa, J.M.; Bezerra, F.H.R.; Freitas Macedo, M.H. de; Pereira, R.

1988-01-01

The Oros belt is situated in the southeastern part of Ceara state, Brazil, and geologically pertains to the Borborema province. This belt comprises a volcano-sedimentary sequence of middle proterozoic age resting unconformably upon basement of Archean/low proterozoic age. In the geological map of Ceara state, this belt displays an elongate shape towards N-S, turning to ENE-WSW in the south, and reaches 12 km wide in the central park. This paper describes the relationships between the country rocks and the supra crustal sequence, as well as the plutonic intrusions and their tectonic metamorphic evolution. New Rb-Sr whole-rock dates are presented which are very important to separate anorogenic and syn-orogenic granites. (author)

Hydrochemical evolution and groundwater flow processes in the Galilee and Eromanga basins, Great Artesian Basin, Australia: a multivariate statistical approach.

Science.gov (United States)

Moya, Claudio E; Raiber, Matthias; Taulis, Mauricio; Cox, Malcolm E

2015-03-01

The Galilee and Eromanga basins are sub-basins of the Great Artesian Basin (GAB). In this study, a multivariate statistical approach (hierarchical cluster analysis, principal component analysis and factor analysis) is carried out to identify hydrochemical patterns and assess the processes that control hydrochemical evolution within key aquifers of the GAB in these basins. The results of the hydrochemical assessment are integrated into a 3D geological model (previously developed) to support the analysis of spatial patterns of hydrochemistry, and to identify the hydrochemical and hydrological processes that control hydrochemical variability. In this area of the GAB, the hydrochemical evolution of groundwater is dominated by evapotranspiration near the recharge area resulting in a dominance of the Na-Cl water types. This is shown conceptually using two selected cross-sections which represent discrete groundwater flow paths from the recharge areas to the deeper parts of the basins. With increasing distance from the recharge area, a shift towards a dominance of carbonate (e.g. Na-HCO3 water type) has been observed. The assessment of hydrochemical changes along groundwater flow paths highlights how aquifers are separated in some areas, and how mixing between groundwater from different aquifers occurs elsewhere controlled by geological structures, including between GAB aquifers and coal bearing strata of the Galilee Basin. The results of this study suggest that distinct hydrochemical differences can be observed within the previously defined Early Cretaceous-Jurassic aquifer sequence of the GAB. A revision of the two previously recognised hydrochemical sequences is being proposed, resulting in three hydrochemical sequences based on systematic differences in hydrochemistry, salinity and dominant hydrochemical processes. The integrated approach presented in this study which combines different complementary multivariate statistical techniques with a detailed assessment of the

Long-term climate change: the evolution of shield surface boundary conditions

International Nuclear Information System (INIS)

Peltier, W.R.

2007-01-01

The Earths surface during the Pleistocene epoch has been repeatedly subjected to glacial cycles that have markedly influenced both the landscape and surface boundary conditions that, in part, governed past evolution of deep-seated Shield groundwater flow domains. As part of the Deep Geologic Repository Technology Programme simulations of the last Laurentide glacial episode have been undertaken with the University of Toronto Glacial System Model (GSM). The purpose of these simulations is to yield constrained predictions of the magnitude and time rate of change of peri-glacial, glacial and boreal regimes that have perturbed Shield flow domains in the geologic past. A detailed model of long timescale climate change has been developed, which is able to make useful predictions of the process of continental glaciation and deglaciation that has occurred in the past due to the small changes in the effective intensity of the Sun at the location of the Earth caused by gravitational many body effects in Solar System evolution. Based upon the success of this model we are able to assert that we have demonstrated a basic understanding of why this process has continually recurred in the past on a timescale of approximately 100 000 years. Continuing work with the Glacial Systems Model and efforts to provide explicit linkage to numerical analyses of sub-surface hydrology are beginning to yield a new understanding of groundwater flow system evolution and response to glacial perturbations. In so doing this understanding is not only providing a reasoned basis on which to examine issues of geosphere stability as relevant to the safety of a hypothetical repository for used nuclear fuel in Shield terrain, but is also offering an improved basis for the integrated interpretation of multi-disciplinary geo-scientific data necessary for development of a descriptive geosphere model that is seen as fundamental to the repository Safety Case. (author)

Long-term characteristics of geological conditions in Japan. Pt. 1. Fundamental concept for future's prediction of geological conditions and the subjects

International Nuclear Information System (INIS)

Tanaka, Kazuhiro; Chigira, Masahiro.

1997-01-01

It is very important to evaluate the long-term stability of geological conditions such as volcanic activity, uplift-subsidence, earthquakes, faulting and sea level change when the long-term safety performance of HLW geological disposal is investigated. We proposed the extrapolation method using the geological date obtained in the geologic time of the last 500 ka to predict the future's tectonic movements in Japan. Furthermore, we extract geological conditions that would affect the long-term safety of HLW geological disposal with regard to direct and indirect radionuclide release scenarios. As a result, it was concluded that volcanic activity and tectonic movements including faulting and uplift-subsidence, should be considered and their surveying system and evaluating method should be developed. (author)

Ontological Encoding of GeoSciML and INSPIRE geological standard vocabularies and schemas: application to geological mapping

Science.gov (United States)

Lombardo, Vincenzo; Piana, Fabrizio; Mimmo, Dario; Fubelli, Giandomenico; Giardino, Marco

2016-04-01

Encoding of geologic knowledge in formal languages is an ambitious task, aiming at the interoperability and organic representation of geological data, and semantic characterization of geologic maps. Initiatives such as GeoScience Markup Language (last version is GeoSciML 4, 2015[1]) and INSPIRE "Data Specification on Geology" (an operative simplification of GeoSciML, last version is 3.0 rc3, 2013[2]), as well as the recent terminological shepherding of the Geoscience Terminology Working Group (GTWG[3]) have been promoting information exchange of the geologic knowledge. There have also been limited attempts to encode the knowledge in a machine-readable format, especially in the lithology domain (see e.g. the CGI_Lithology ontology[4]), but a comprehensive ontological model that connect the several knowledge sources is still lacking. This presentation concerns the "OntoGeonous" initiative, which aims at encoding the geologic knowledge, as expressed through the standard vocabularies, schemas and data models mentioned above, through a number of interlinked computational ontologies, based on the languages of the Semantic Web and the paradigm of Linked Open Data. The initiative proceeds in parallel with a concrete case study, concerning the setting up of a synthetic digital geological map of the Piemonte region (NW Italy), named "GEOPiemonteMap" (developed by the CNR Institute of Geosciences and Earth Resources, CNR IGG, Torino), where the description and classification of GeologicUnits has been supported by the modeling and implementation of the ontologies. We have devised a tripartite ontological model called OntoGeonous that consists of: 1) an ontology of the geologic features (in particular, GeologicUnit, GeomorphologicFeature, and GeologicStructure[5], modeled from the definitions and UML schemata of CGI vocabularies[6], GeoScienceML and INSPIRE, and aligned with the Planetary realm of NASA SWEET ontology[7]), 2) an ontology of the Earth materials (as defined by the

Geoillustrator - fast sketching of geological illustrations and animations

Science.gov (United States)

Patel, Daniel; Langeland, Tor; Solteszova, Veronika

2014-05-01

We present our research results in the Geoillustrator project. The project has been going for four years and is ending in March. It was aimed at developing a rapid sketching tool for generating geological illustrations and animations for understanding the processes that have led to a current subsurface configuration. The sketching tool facilitates effective dissemination of ideas, e.g. through generation of interactive geo-scientific illustrations for interdisciplinary communication and communication to decision makers, media and lay persons. This can improve work processes in early phases of oil and gas exploration where critical decisions have to be taken based on limited information. It is a challenge for involved specialists in early exploration phases to externalize their ideas, and effectively achieve consensus in multidisciplinary working groups. In these work processes, a tool for rapid sketching of geology would be very useful for expressing geological hypotheses and creating and comparing different evolution scenarios. Often, decisions are influenced by factors that are not relevant, e.g. the geologists who produce the most polished illustrations of their hypothesis have a higher probability for getting their theories through to decision makers as it is more clearly communicated. This results in a competitive advantage for geologists who are skilled in creating illustrations. Having a tool that would lift the ability of all geologists to express their ideas to an equal level would result in more alternatives and better foundation for decision making. Digital sketching will also allow capturing otherwise lost material which can constitute a large amount of mental work and ideas. The results of sketching are currently scrapped as paper or erased from the blackboard or exist only as rough personal sketches. By using a digital sketching tool, the sketches can be exported to a form usable in modelling tools used in later phases of exploration. Currently, no

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.)

Geological setting, emplacement mechanism and igneous evolution of the Atchiza mafic-ultramafic layered suite in north-west Mozambique

Science.gov (United States)

Ibraimo, Daniel Luis; Larsen, Rune B.

2015-11-01

The Atchiza mafic and ultramafic-layered suite (hereafter, "Atchiza Suite) crops out in an area 330 km2 west of the Mozambican Tete province. In an early account of the geology of this intrusion, it was considered the continuation of the Great Dyke of Zimbabwe, an idea that was aborted after detailed studies. Nevertheless, the Ni concentrations in the Atchiza outcrop rocks are considerable. Our investigation used field evidence, hand specimens and petrography descriptions, mineral chemistry studies using electron microprobe analysis and tectonic analysis to arrive at a plausible mineralogical composition and understanding of the tectonic setting for the igneous evolution. The mineral composition from the Atchiza Suite indicates that these are cumulates. The magmatic segregation from the petrographic and mineral composition reasoning indicates that dunite-lherzolitic peridotite-olivine gabbro-gabbronorite-gabbro-pegmatitic gabbro is the rock formation sequence. Olivine and chromite were the first phases formed, followed by pyroxene and plagioclase. In addition, it is shown that these minerals are near-liquidus crystallization products of basaltic magma with olivine Fo: 87.06 in dunite, mean values of clinopyroxene are (Wo: 36.4, En: 48.0, Fs: 15.2), orthopyroxene (Wo: 2.95, En: 73.0, Fs: 24.2) and plagioclase An: 71.3, respectively. Opaque minerals comprise Fe-Ti oxides and (Fe, Cr) spinel up to 4.8 vol.%, but chromitite layers are not present. Most of the opaque minerals are interstitial to pyroxene. Sulphides are common in gabbros, with pyrrhotite, pentlandite, chalcopyrite, pyrite and covellite together comprising 0.4-2.0 vol.%. The whole rock Rare Earth Element (REE) concentrations are mainly a result of differentiation, but slight crustal contamination/assimilation contributed to the REE contents. In addition, they also show Eu enrichment, suggesting that plagioclase fractionation was important in the rock. The Atchiza Suite preserves a deep-seated plumbing

Geologic Interpretation of Data Sets Collected by Planetary Analog Geology Traverses and by Standard Geologic Field Mapping. Part 1; A Comparison Study

Science.gov (United States)

Eppler, Dean B.; Bleacher, Jacob F.; Evans, Cynthia A.; Feng, Wanda; Gruener, John; Hurwitz, Debra M.; Skinner, J. A., Jr.; Whitson, Peggy; Janoiko, Barbara

2013-01-01

Geologic maps integrate the distributions, contacts, and compositions of rock and sediment bodies as a means to interpret local to regional formative histories. Applying terrestrial mapping techniques to other planets is challenging because data is collected primarily by orbiting instruments, with infrequent, spatiallylimited in situ human and robotic exploration. Although geologic maps developed using remote data sets and limited "Apollo-style" field access likely contain inaccuracies, the magnitude, type, and occurrence of these are only marginally understood. This project evaluates the interpretative and cartographic accuracy of both field- and remote-based mapping approaches by comparing two 1:24,000 scale geologic maps of the San Francisco Volcanic Field (SFVF), north-central Arizona. The first map is based on traditional field mapping techniques, while the second is based on remote data sets, augmented with limited field observations collected during NASA Desert Research & Technology Studies (RATS) 2010 exercises. The RATS mission used Apollo-style methods not only for pre-mission traverse planning but also to conduct geologic sampling as part of science operation tests. Cross-comparison demonstrates that the Apollo-style map identifies many of the same rock units and determines a similar broad history as the field-based map. However, field mapping techniques allow markedly improved discrimination of map units, particularly unconsolidated surficial deposits, and recognize a more complex eruptive history than was possible using Apollo-style data. Further, the distribution of unconsolidated surface units was more obvious in the remote sensing data to the field team after conducting the fieldwork. The study raises questions about the most effective approach to balancing mission costs with the rate of knowledge capture, suggesting that there is an inflection point in the "knowledge capture curve" beyond which additional resource investment yields progressively

Bedrock Geologic Map of Woodstock, Vermont

Data.gov (United States)

Vermont Center for Geographic Information — Digital Data from VG06-4 Thompson, P. J., 2006, Bedrock Geologic Map of Woodstock, Vermont: VGS Open-File Report VG06-4, scale 1:24,000. The bedrock geologic map...

Digital geologic map in the scale 1:50 000

International Nuclear Information System (INIS)

Kacer, S.; Antalik, M.

2005-01-01

In this presentation authors present preparation of new digital geologic map of the Slovak Republic. This map is prepared by the State Geological Institute of Dionyz Stur as a part of the project Geological information system GeoIS. One of the basic information geologic layers, which will be accessible on the web-site will be digital geologic map of the Slovak Republic in the scale 1: 50 000

Geologic sources of energy

Science.gov (United States)

Bundtzen, Thomas K.; Nokleberg, Warren J.; Bundtzen, Thomas K.; Nokleberg, Warren J.; Price, Raymond A.; Scholl, David W.; Stone, David B.

2017-01-01

This chapter describes the exploration, development, and geologic setting of petroleum resources (including tar sands), coal resources (including coalbed methane), and geothermal energy resources of the Northern Cordillera.For petroleum resources, the chapter describes: (1) the history of petroleum development and production, first for Alaska and then for the Canadian Cordillera; and (2) generalized basin analysis geologic settings for the six major petroleum basins that are illustrated in summary maps and cross sections. Subsequent sections of the chapter describe the nature and geologic setting of tar sand resources, geothermal energy resources, and coal resources. The area distribution of the energy resources of the region are depicted in the Energy Resources Map that has multiple layers that can be displayed in various arrangements. Employing this map in a separate window while reading the text will be greatly beneficial. Many geographic names are employed in the descriptions throughout this chapter. While reading this chapter, viewing the Geographic Regions Layer of the Energy Resources Map, as needed, will be valuable.

Attraction of the opposites: reception of the Theory of Evolution in Young Earth creationists

Directory of Open Access Journals (Sweden)

Alexander Khramov

2018-12-01

Full Text Available The history of the Young Earth creationism can be divided into two stages, namely the period of Scriptural geology, which lasted from the 1820s to the 1860s mostly in Britain, and the modern period, which began in the USA in the 1920s and continued into the 21st century. During both these periods, some Young-Earth creationists made attempts to employ the notions of evolution in order to bolster a highly literalistic interpretation of the biblical narrative about the Creation and the Flood. In their opinion, the hypothesis of ultra-rapid evolution off ered a plausible explanation of how a small number of species which were in Noah’s Ark could have produced the very diverse modern fauna of terrestrial organisms without supernatural interventions on the part of God. The fact that the elements of the theory of evolution were accepted by some prominent Young Earth creationists demonstrates that it would be an exaggeration to ascribe uncompromised hostility towards the idea of evolution to the Young Earth movement as a whole.

New insights into the stratigraphic, paleogeographic and tectonic evolution and petroleum potential of Kerkennah Islands, Eastern Tunisia

Science.gov (United States)

Elfessi, Maroua

2017-01-01

This work presents general insights into the stratigraphic and paleogeographic evolution as well as the structural architecture and the petroleum potential of Kerkennah Islands, located in the Eastern Tunisia Foreland, from Cenomanian to Pliocene times. Available data from twenty wells mostly drilled in Cercina and Chergui fields are used to establish three lithostratigraphic correlations as well as isopach and isobath maps in order to point out thickness and depth variations of different geological formations present within our study area; in addition to a synthetic log and isoporosity map of the main carbonate reservoir (the nummulites enriched Reineche Member). The integrated geological study reveals relatively condensed but generally continuous sedimentation and a rugged substrate with horsts, grabens and tilted blocks due to the initiation and the individualization of Kerkennah arch throughout the studied geological times. Furthermore, a relationship was highlighted between the evolution of our study zone and those of Sirt basin, Western Mediterranean Sea and Pelagian troughs; this relationship is due to the outstanding location of Kerkennah Islands. The main Bou Dabbous source rock is thicker and more mature within the central-east of the Gulf of Gabes indicating therefore the southeast charge of Reineche reservoir which shows NW-SE trending tilted block system surrounded by normal faults representing the hydrocarbon migration pathways. Besides, the thick Oligo-Miocene formations deposited during the collapse of the Pelagian block caused the maturation of the Ypresian source rock, while the Pliocene unconformity allowed basin inversion and hydrocarbon migration.

Tyrant dinosaur evolution tracks the rise and fall of Late Cretaceous oceans.

Science.gov (United States)

Loewen, Mark A; Irmis, Randall B; Sertich, Joseph J W; Currie, Philip J; Sampson, Scott D

2013-01-01

The Late Cretaceous (∼95-66 million years ago) western North American landmass of Laramidia displayed heightened non-marine vertebrate diversity and intracontinental regionalism relative to other latest Cretaceous Laurasian ecosystems. Processes generating these patterns during this interval remain poorly understood despite their presumed role in the diversification of many clades. Tyrannosauridae, a clade of large-bodied theropod dinosaurs restricted to the Late Cretaceous of Laramidia and Asia, represents an ideal group for investigating Laramidian patterns of evolution. We use new tyrannosaurid discoveries from Utah--including a new taxon which represents the geologically oldest member of the clade--to investigate the evolution and biogeography of Tyrannosauridae. These data suggest a Laramidian origin for Tyrannosauridae, and implicate sea-level related controls in the isolation, diversification, and dispersal of this and many other Late Cretaceous vertebrate clades.

GDA (Geologic Data Assistant), an ArcPad extension for geologic mapping: code, prerequisites, and instructions

Science.gov (United States)

,

2006-01-01

GDA (Geologic Data Assistant) is an extension to ArcPad, a mobile mapping software program by Environmental Systems Research Institute (ESRI) designed to run on personal digital assistant (PDA) computers. GDA and ArcPad allow a PDA to replace the paper notebook and field map traditionally used for geologic mapping. GDA allows easy collection of field data.

The role of post-collisional strike-slip tectonics in the geological evolution of the late Neoproterozoic volcano-sedimentary Guaratubinha Basin, southern Brazil

Science.gov (United States)

Barão, Leonardo M.; Trzaskos, Barbara; Vesely, Fernando F.; de Castro, Luís Gustavo; Ferreira, Francisco J. F.; Vasconcellos, Eleonora M. G.; Barbosa, Tiago C.

2017-12-01

The Guaratubinha Basin is a late Neoproterozoic volcano-sedimentary basin included in the transitional-stage basins of the South American Platform. The aim of this study is to investigate its tectonic evolution through a detailed structural analysis based on remote sensing and field data. The structural and aerogeophysics data indicate that at least three major deformational events affected the basin. Event E1 caused the activation of the two main basin-bounding fault zones, the Guaratubinha Master Fault and the Guaricana Shear Zone. These structures, oriented N20-45E, are associated with well-defined right-lateral to oblique vertical faults, conjugate normal faults and vertical flow structures. Progressive transtensional deformation along the two main fault systems was the main mechanism for basin formation and the deposition of thick coarse-grained deposits close to basin-borders. The continuous opening of the basin provided intense intermediate and acid magmatism as well as deposition of volcaniclastic sediments. Event E2 characterizes generalized compression, recorded as minor thrust faults with tectonic transport toward the northwest and left-lateral activation of the NNE-SSW Palmital Shear Zone. Event E3 is related to the Mesozoic tectonism associated with the South Atlantic opening, which generated diabase dykes and predominantly right-lateral strike-slip faults oriented N10-50W. Its rhomboidal geometry with long axis parallel to major Precambrian shear zones, the main presence of high-angle, strike-slip or oblique faults, the asymmetric distribution of geological units and field evidence for concomitant Neoproterozoic magmatism and strike-slip movements are consistent with pull-apart basins reported in the literature.

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)

Geologic Field Database

Directory of Open Access Journals (Sweden)

Katarina Hribernik

2002-12-01

Full Text Available The purpose of the paper is to present the field data relational database, which was compiled from data, gathered during thirty years of fieldwork on the Basic Geologic Map of Slovenia in scale1:100.000. The database was created using MS Access software. The MS Access environment ensures its stability and effective operation despite changing, searching, and updating the data. It also enables faster and easier user-friendly access to the field data. Last but not least, in the long-term, with the data transferred into the GISenvironment, it will provide the basis for the sound geologic information system that will satisfy a broad spectrum of geologists’ needs.

Paleoclimates and geomorphological evolution of the Carajas region: geochemical and geochronological evidence

International Nuclear Information System (INIS)

Vasconcelos, P.M.

1996-01-01

Based on the geochronological results, on the petrographical and geochemical observations and considering the experimental evidences that suggests a great influence of the organic processes in the Manganese geochemistry it's possible to conclude that the dissolution and reprecipitation events of the Manganese oxides in the Carajas region, Para State, Brazil, represents humid and hot periods in the geological history of the region. The weathering dating furnishes information about the continental evolution in the Mesozoic/Cenozoic, difficult or impossible to determine by another methods

Safety analysis of geologic containment of long life radioactive wastes. Critical assessment of existing methods and proposition of prospective approach

International Nuclear Information System (INIS)

Masure, P.; Gedefroy, P.; Imauven, C.

1983-01-01

Existing methods of risk analysis applied to disposal of long-lived radioactive waste in geologic formations are rewieved. A prospective analysis method for containment performances is proposed, deduced in the burial system from the combination of interaction between wastes, repository, host rock, surrounding geosphere, of natural evolution of each component of the system, sudden or chance events that could break waste containment. The method is based on the elaboration of four basic schemes graded in difficulties to facilitate comparisons

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

Constructing a Geology Ontology Using a Relational Database

Science.gov (United States)

Hou, W.; Yang, L.; Yin, S.; Ye, J.; Clarke, K.

2013-12-01

In geology community, the creation of a common geology ontology has become a useful means to solve problems of data integration, knowledge transformation and the interoperation of multi-source, heterogeneous and multiple scale geological data. Currently, human-computer interaction methods and relational database-based methods are the primary ontology construction methods. Some human-computer interaction methods such as the Geo-rule based method, the ontology life cycle method and the module design method have been proposed for applied geological ontologies. Essentially, the relational database-based method is a reverse engineering of abstracted semantic information from an existing database. The key is to construct rules for the transformation of database entities into the ontology. Relative to the human-computer interaction method, relational database-based methods can use existing resources and the stated semantic relationships among geological entities. However, two problems challenge the development and application. One is the transformation of multiple inheritances and nested relationships and their representation in an ontology. The other is that most of these methods do not measure the semantic retention of the transformation process. In this study, we focused on constructing a rule set to convert the semantics in a geological database into a geological ontology. According to the relational schema of a geological database, a conversion approach is presented to convert a geological spatial database to an OWL-based geological ontology, which is based on identifying semantics such as entities, relationships, inheritance relationships, nested relationships and cluster relationships. The semantic integrity of the transformation was verified using an inverse mapping process. In a geological ontology, an inheritance and union operations between superclass and subclass were used to present the nested relationship in a geochronology and the multiple inheritances

A preliminary study on the geochemical environment for deep geological disposal of high level radioactive waste in Korea

Energy Technology Data Exchange (ETDEWEB)

Kim, Chun Soo; Bae, Dae Seok; Kim, Kyung Su; Koh, Yong Kwon; Park, Byoung Yun

2000-03-01

Geochemical study on the groundwater from crystalline rocks (granite and gneiss) for the deep geological disposal of high-level radioactive waste was carried out in order to elucidate the hydrogeochemical and isotope characteristics and geochemical evolution of the groundwater. Study areas are Jungwon, Chojeong, Youngcheon and Yusung for granite region, Cheongyang for gneiss region, and Yeosu for volcanic region. Groundwaters of each study areas weree sampled and analysed systematically. Groundwaters can be grouped by their chemistry and host rock. Origin of the groundwater was proposed by isotope ({sup 18}O, {sup 2}H, {sup 13}C, {sup 34}S, {sup 87}Sr, {sup 15}N) studies and the age of groundwater was inferred from their tritium contents. Based ont the geochemical and isotope characteristics, the geochemical evolutions of each types of groundwater were simulated using SOLVEQ/CHILLER and PHREEQC programs.

Geologic map of Big Bend National Park, Texas

Science.gov (United States)

Turner, Kenzie J.; Berry, Margaret E.; Page, William R.; Lehman, Thomas M.; Bohannon, Robert G.; Scott, Robert B.; Miggins, Daniel P.; Budahn, James R.; Cooper, Roger W.; Drenth, Benjamin J.; Anderson, Eric D.; Williams, Van S.

2011-01-01

The purpose of this map is to provide the National Park Service and the public with an updated digital geologic map of Big Bend National Park (BBNP). The geologic map report of Maxwell and others (1967) provides a fully comprehensive account of the important volcanic, structural, geomorphological, and paleontological features that define BBNP. However, the map is on a geographically distorted planimetric base and lacks topography, which has caused difficulty in conducting GIS-based data analyses and georeferencing the many geologic features investigated and depicted on the map. In addition, the map is outdated, excluding significant data from numerous studies that have been carried out since its publication more than 40 years ago. This report includes a modern digital geologic map that can be utilized with standard GIS applications to aid BBNP researchers in geologic data analysis, natural resource and ecosystem management, monitoring, assessment, inventory activities, and educational and recreational uses. The digital map incorporates new data, many revisions, and greater detail than the original map. Although some geologic issues remain unresolved for BBNP, the updated map serves as a foundation for addressing those issues. Funding for the Big Bend National Park geologic map was provided by the United States Geological Survey (USGS) National Cooperative Geologic Mapping Program and the National Park Service. The Big Bend mapping project was administered by staff in the USGS Geology and Environmental Change Science Center, Denver, Colo. Members of the USGS Mineral and Environmental Resources Science Center completed investigations in parallel with the geologic mapping project. Results of these investigations addressed some significant current issues in BBNP and the U.S.-Mexico border region, including contaminants and human health, ecosystems, and water resources. Funding for the high-resolution aeromagnetic survey in BBNP, and associated data analyses and

The 3-D geological model around Chang'E-3 landing site based on lunar penetrating radar Channel 1 data

Science.gov (United States)

Yuan, Yuefeng; Zhu, Peimin; Zhao, Na; Xiao, Long; Garnero, Edward; Xiao, Zhiyong; Zhao, Jiannan; Qiao, Le

2017-07-01

High-frequency lunar penetrating radar (LPR) data from an instrument on the lunar rover Yutu, from the Chang'E-3 (CE-3) robotic lander, were used to build a three-dimensional (3-D) geological model of the lunar subsurface structure. The CE-3 landing site is in the northern Mare Imbrium. More than five significant reflection horizons are evident in the LPR profile, which we interpret as different period lava flow sequences deposited on the lunar surface. The most probable directions of these flows were inferred from layer depths, thicknesses, and other geological information. Moreover, the apparent Imbrian paleoregolith homogeneity in the profile supports the suggestion of a quiescent period of lunar surface evolution. Similar subsurface structures are found at the NASA Apollo landing sites, indicating that the cause and time of formation of the imaged phenomena may be similar between the two distant regions.

Canadian geologic isolation program

International Nuclear Information System (INIS)

Dyne, P.J.

1976-01-01

The Canadian geologic isolation program is directed at examining the potential of (1) salt deposits and (2) hard rock as repositories for radioactive wastes. It was felt essential from the inception that alternative host rocks be evaluated over a fairly large geographical area. The studies on salt deposits to date are based on existing geological information and have identified the areas that show some potential and merit further study. The factors considered include depth, thickness and purity of the deposit, overlying aquifers, and the potential for gas and oil exploration as well as potash recovery. The studies on hard rock are restricted to plutonic igneous rocks in the Ontario part of the Canadian Shield. Because geological information on their nature and extent is sparse, the study is limited to bodies that are well exposed and for which information is available.for which information is available. Field studies in the next two seasons are aimed at mapping the fault and joint patterns and defining the geologic controls on their development. In 1977 and 1978, two or three of the more favorable sites will be mapped in greater detail, and an exploratory drilling program will be established to determine the extent of fracturing at depth and the hydrology of these fractures. Conceptual designs of mined repositories in hard rock are also being made with the hope of identifying, at an early stage in this program, special problems in hard-rock repositories that may require development and study

Geology and Design: Formal and Rational Connections

Science.gov (United States)

Eriksson, S. C.; Brewer, J.

2016-12-01

Geological forms and the manmade environment have always been inextricably linked. From the time that Upper Paleolithic man created drawings in the Lascaux Caves in the southwest of France, geology has provided a critical and dramatic spoil for human creativity. This inspiration has manifested itself in many different ways, and the history of architecture is rife with examples of geologically derived buildings. During the early 20th Century, German Expressionist art and architecture was heavily influenced by the natural and often translucent quality of minerals. Architects like Bruno Taut drew and built crystalline forms that would go on to inspire the more restrained Bauhaus movement. Even within the context of Contemporary architecture, geology has been a fertile source for inspiration. Architectural practices across the globe leverage the rationality and grounding found in geology to inform a process that is otherwise dominated by computer-driven parametric design. The connection between advanced design technology and the beautifully realized geo natural forms insures that geology will be a relevant source of architectural inspiration well into the 21st century. The sometimes hidden relationship of geology to the various sub-disciplines of Design such as Architecture, Interiors, Landscape Architecture, and Historic Preservation is explored in relation to curriculum and the practice of design. Topics such as materials, form, history, the cultural and physical landscape, natural hazards, and global design enrich and inform curriculum across the college. Commonly, these help define place-based education.

Assessing the effects of human action on the safety of geologic disposal: the U.S. regulatory experience

International Nuclear Information System (INIS)

Schultheisz, D.

2010-01-01

There is general agreement that geologic disposal of long-lived radioactive waste provides the greatest degree of isolation from the biosphere, and hence the greatest protection for humans, over the extended time frames during which the waste presents a hazard. Geologic disposal has an additional advantage in that it does not rely on active institutional controls to maintain and protect the facility, but is instead intended to operate passively even if all knowledge of the facility is lost. Thus, geologic disposal does not rely on the questionable assumption that governmental or other responsible institutions can be maintained in perpetuity; this, however, also raises the possibility that some future human action could be taken that disrupts the repository and compromises its ability to isolate the radioactive material. It is clear, therefore, that some evaluation of this possibility must be included in the overall safety case for the facility. The nature and extent of the analysis, as well as the relative importance it is assigned within the safety case, is less clear. The U.S. Environmental Protection Agency (EPA) has applied two very different approaches to the analysis of human intrusion scenarios at geologic disposal facilities. For the Waste Isolation Pilot Plant (WIPP) in New Mexico, which accepts transuranic radioactive waste from government defence activities, realistic drilling and mining scenarios are analyzed as part of the safety assessment addressing the natural (undisturbed) evolution of the repository. (40 CFR 194.32 and 194.33) For the proposed repository for spent nuclear fuel and high-level radioactive waste at Yucca Mountain, Nevada, however, a specified stylised drilling scenario is analyzed separately from the safety assessment for the undisturbed evolution of the disposal system. (40 CFR 197.25 ) What is the basis for these different approaches? How can they both be 'right'? The answer lies in the details of the two facilities, specifically

36 CFR 902.59 - Geological and geophysical information.

Science.gov (United States)

2010-07-01

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

Uruguayan South Geology

International Nuclear Information System (INIS)

Guillemain, H.

1980-01-01

This monograph is about the sedimentary geological formation in the southern of Uruguay. According to the previous Gondwana studies there are several concordances between the Uruguayan and Brazilian ground.

Semantics-informed cartography: the case of Piemonte Geological Map

Science.gov (United States)

Piana, Fabrizio; Lombardo, Vincenzo; Mimmo, Dario; Giardino, Marco; Fubelli, Giandomenico

2016-04-01

In modern digital geological maps, namely those supported by a large geo-database and devoted to dynamical, interactive representation on WMS-WebGIS services, there is the need to provide, in an explicit form, the geological assumptions used for the design and compilation of the database of the Map, and to get a definition and/or adoption of semantic representation and taxonomies, in order to achieve a formal and interoperable representation of the geologic knowledge. These approaches are fundamental for the integration and harmonisation of geological information and services across cultural (e.g. different scientific disciplines) and/or physical barriers (e.g. administrative boundaries). Initiatives such as GeoScience Markup Language (last version is GeoSciML 4.0, 2015, http://www.geosciml.org) and the INSPIRE "Data Specification on Geology" http://inspire.jrc.ec.europa.eu/documents/Data_Specifications/INSPIRE_DataSpecification_GE_v3.0rc3.pdf (an operative simplification of GeoSciML, last version is 3.0 rc3, 2013), as well as the recent terminological shepherding of the Geoscience Terminology Working Group (GTWG) have been promoting information exchange of the geologic knowledge. Grounded on these standard vocabularies, schemas and data models, we provide a shared semantic classification of geological data referring to the study case of the synthetic digital geological map of the Piemonte region (NW Italy), named "GEOPiemonteMap", developed by the CNR Institute of Geosciences and Earth Resources, Torino (CNR IGG TO) and hosted as a dynamical interactive map on the geoportal of ARPA Piemonte Environmental Agency. The Piemonte Geological Map is grounded on a regional-scale geo-database consisting of some hundreds of GeologicUnits whose thousands instances (Mapped Features, polygons geometry) widely occur in Piemonte region, and each one is bounded by GeologicStructures (Mapped Features, line geometry). GeologicUnits and GeologicStructures have been spatially

Safety assessment of HLW geological disposal system