Sample records for fundamental geological processes

  1. Sea Level Change, A Fundamental Process When Interpreting Coastal Geology and Geography.

    ERIC Educational Resources Information Center

    Zeigler, John M.

    1985-01-01

    Discusses the meaning of sea level change and identifies the major factors responsible for this occurrence. Elaborates on the theory and processes involved in indirect measurement of changes in sea volume. Also explains how crustal movement affects sea level. (ML)

  2. Geological processes and evolution

    USGS Publications Warehouse

    Head, J.W.; Greeley, R.; Golombek, M.P.; Hartmann, W.K.; Hauber, E.; Jaumann, R.; Masson, P.; Neukum, G.; Nyquist, L.E.; Carr, M.H.

    2001-01-01

    Geological mapping and establishment of stratigraphic relationships provides an overview of geological processes operating on Mars and how they have varied in time and space. Impact craters and basins shaped the crust in earliest history and as their importance declined, evidence of extensive regional volcanism emerged during the Late Noachian. Regional volcanism characterized the Early Hesperian and subsequent to that time, volcanism was largely centered at Tharsis and Elysium, continuing until the recent geological past. The Tharsis region appears to have been largely constructed by the Late Noachian, and represents a series of tectonic and volcanic centers. Globally distributed structural features representing contraction characterize the middle Hesperian. Water-related processes involve the formation of valley networks in the Late Noachian and into the Hesperian, an ice sheet at the south pole in the middle Hesperian, and outflow channels and possible standing bodies of water in the northern lowlands in the Late Hesperian and into the Amazonian. A significant part of the present water budget occurs in the present geologically young polar layered terrains. In order to establish more firmly rates of processes, we stress the need to improve the calibration of the absolute timescale, which today is based on crater count systems with substantial uncertainties, along with a sampling of rocks of unknown provenance. Sample return from carefully chosen stratigraphic units could calibrate the existing timescale and vastly improve our knowledge of Martian evolution.

  3. Coastal Geological Processes

    NSDL National Science Digital Library

    Coastlines are places of continuous, often dramatic geological activity. They change daily and seasonally, but especially over long time periods. This interactive feature discusses the forces that help shape coastal landforms like cliffs and beaches. Topics include waves, tides, and currents; weathering, erosion, and deposition; and other factors, such as the activity of organisms and human modifications. A background essay and discussion questions are included.

  4. Fundamental processes in ion plating

    SciTech Connect

    Mattox, D.M.

    1980-01-01

    Ion plating is a generic term applied to film deposition processes in which the substrate surface and/or the depositing film is subjected to a flux of high energy particles sufficient to cause changes in the interfacial region of film properties compared to a nonbombarded deposition. Ion plating is being accepted as an alternative coating technique to sputter deposition, vacuum evaporation and electroplating. In order to intelligently choose between the various deposition techniques, the fundamental mechanisms, relating to ion plating, must be understood. This paper reviews the effects of low energy ion bombardment on surfaces, interface formation and film development as they apply to ion plating and the implementation and applications of the ion plating process.

  5. Processes of Geology

    NASA Technical Reports Server (NTRS)

    2003-01-01

    [figure removed for brevity, see original site]

    Released 16 July 2003

    This THEMIS visible image captures a complex process of deposition, burial and exhumation. The crater ejecta in the top of the image is in the form of flow lobes, indicating that the crater was formed in volatile-rich terrain. While a radial pattern can be seen in the ejecta, the pattern is sharper in the lower half of the ejecta. This is because the top half of the ejecta is still buried by a thin layer of sediment. It is most likely that at one time the entire area was covered. Wind, and perhaps water erosion have started to remove this layer, once again exposing the what was present underneath.

    Image information: VIS instrument. Latitude -34.3, Longitude 181.2 East (178.8 West). 19 meter/pixel resolution.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  6. Fundamentals of Image Processing Ian T. Young

    E-print Network

    van Vliet, Lucas J.

    Fundamentals of Image Processing Ian T. Young Jan J. Gerbrands Lucas J. van Vliet #12;CIP OF IMAGE PROCESSING ISBN 90­75691­01­7 NUGI 841 Subject headings: Digital Image Processing / Digital Image of Technology. #12;Fundamentals of Image Processing 1. Introduction

  7. Fundamentals of distributed processing systems

    SciTech Connect

    Provins, G.

    1984-01-01

    The major concepts, goals and techniques of distributed processing when implemented in real-time plant information and control systems are presented. Approaches to meeting the communication requirements and system security aspects are discussed with special emphasis being given to hardware modularity and functional partitioning.

  8. Health benefits of geologic materials and geologic processes

    USGS Publications Warehouse

    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.

  9. Comparison Charts of Geological Processes: Terrestrial Planets

    NSDL National Science Digital Library

    This chart presents information on the geological processes (volcanism, impact cratering, tectonics, and gradation) that have affected the Earth, Moon, and the terrestrial planets. Students compare the effects these processes have had on the Moon and planets. There is also a blank chart and a sheet of notes on the geological processes that may be used in conjunction with this chart. This chart is one of the activities for the Exploring Planets in the Classroom's Introduction to the Solar System.

  10. Measurement and Fundamental Processes in Quantum Mechanics

    NASA Astrophysics Data System (ADS)

    Jaeger, Gregg

    2015-07-01

    In the standard mathematical formulation of quantum mechanics, measurement is an additional, exceptional fundamental process rather than an often complex, but ordinary process which happens also to serve a particular epistemic function: during a measurement of one of its properties which is not already determined by a preceding measurement, a measured system, even if closed, is taken to change its state discontinuously rather than continuously as is usual. Many, including Bell, have been concerned about the fundamental role thus given to measurement in the foundation of the theory. Others, including the early Bohr and Schwinger, have suggested that quantum mechanics naturally incorporates the unavoidable uncontrollable disturbance of physical state that accompanies any local measurement without the need for an exceptional fundamental process or a special measurement theory. Disturbance is unanalyzable for Bohr, but for Schwinger it is due to physical interactions' being borne by fundamental particles having discrete properties and behavior which is beyond physical control. Here, Schwinger's approach is distinguished from more well known treatments of measurement, with the conclusion that, unlike most, it does not suffer under Bell's critique of quantum measurement. Finally, Schwinger's critique of measurement theory is explicated as a call for a deeper investigation of measurement processes that requires the use of a theory of quantum fields.

  11. Fundamental issues in the geology and geophysics of venus.

    PubMed

    Solomon, S C; Head, J W

    1991-04-12

    A number of important and currently unresolved issues in the global geology and geophysics of Venus will be addressable with the radar imaging, altimetry, and gravity measurements now forthcoming from the Magellan mission. Among these are the global volcanic flux and the rate of formation of new crust; the global heat flux and its regional variations; the relative importance of localized hot spots and linear centers of crustal spreading to crustal formation and tectonics; and the planform of mantle convection on Venus and the nature of the interactions among interior convective flow, near-surface deformation and magmatism. PMID:17769271

  12. Migration of radionuclides in geologic media: Fundamental research needs

    SciTech Connect

    Reed, D.T. (Argonne National Lab., IL (USA)); Zachara, J.M.; Wildung, R.E. (Pacific Northwest Lab., Richland, WA (USA)); Wobber, F.J. (USDOE, Washington, DC (USA))

    1990-01-01

    An assessment of the fundamental research needs in understanding and predicting the migration of radionuclides in the subsurface is provided. Emphasis is on the following three technical areas: (1) aqueous speciation of radionuclides, (2) the interaction of radionuclides with substrates, and (3) intermediate-scale interaction studies. This research relates to important issues associated with environmental restoration and remediation of DOE sites contaminated with mixed radionuclide-organic wastes. 64 refs., 1 fig., 1 tab.

  13. Fundamental optical processes in armchair carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Hįroz, Erik H.; Duque, Juan G.; Tu, Xiaomin; Zheng, Ming; Hight Walker, Angela R.; Hauge, Robert H.; Doorn, Stephen K.; Kono, Junichiro

    2013-01-01

    Single-wall carbon nanotubes provide ideal model one-dimensional (1-D) condensed matter systems in which to address fundamental questions in many-body physics, while, at the same time, they are leading candidates for building blocks in nanoscale optoelectronic circuits. Much attention has been recently paid to their optical properties, arising from 1-D excitons and phonons, which have been revealed via photoluminescence, Raman scattering, and ultrafast optical spectroscopy of semiconducting carbon nanotubes. On the other hand, dynamical properties of metallic nanotubes have been poorly explored, although they are expected to provide a novel setting for the study of electron-hole pairs in the presence of degenerate 1-D electrons. In particular, (n,n)-chirality, or armchair, metallic nanotubes are truly gapless with massless carriers, ideally suited for dynamical studies of Tomonaga-Luttinger liquids. Unfortunately, progress towards such studies has been slowed by the inherent problem of nanotube synthesis whereby both semiconducting and metallic nanotubes are produced. Here, we use post-synthesis separation methods based on density gradient ultracentrifugation and DNA-based ion-exchange chromatography to produce aqueous suspensions strongly enriched in armchair nanotubes. Through resonant Raman spectroscopy of the radial breathing mode phonons, we provide macroscopic and unambiguous evidence that density gradient ultracentrifugation can enrich ensemble samples in armchair nanotubes. Furthermore, using conventional, optical absorption spectroscopy in the near-infrared and visible range, we show that interband absorption in armchair nanotubes is strongly excitonic. Lastly, by examining the G-band mode in Raman spectra, we determine that observation of the broad, lower frequency (G-) feature is a result of resonance with non-armchair ``metallic'' nanotubes. These findings regarding the fundamental optical absorption and scattering processes in metallic carbon nanotubes lay the foundation for further spectroscopic studies to probe many-body physical phenomena in one dimension.

  14. Fundamental optical processes in armchair carbon nanotubes.

    PubMed

    Hįroz, Erik H; Duque, Juan G; Tu, Xiaomin; Zheng, Ming; Hight Walker, Angela R; Hauge, Robert H; Doorn, Stephen K; Kono, Junichiro

    2013-02-21

    Single-wall carbon nanotubes provide ideal model one-dimensional (1-D) condensed matter systems in which to address fundamental questions in many-body physics, while, at the same time, they are leading candidates for building blocks in nanoscale optoelectronic circuits. Much attention has been recently paid to their optical properties, arising from 1-D excitons and phonons, which have been revealed via photoluminescence, Raman scattering, and ultrafast optical spectroscopy of semiconducting carbon nanotubes. On the other hand, dynamical properties of metallic nanotubes have been poorly explored, although they are expected to provide a novel setting for the study of electron-hole pairs in the presence of degenerate 1-D electrons. In particular, (n,n)-chirality, or armchair, metallic nanotubes are truly gapless with massless carriers, ideally suited for dynamical studies of Tomonaga-Luttinger liquids. Unfortunately, progress towards such studies has been slowed by the inherent problem of nanotube synthesis whereby both semiconducting and metallic nanotubes are produced. Here, we use post-synthesis separation methods based on density gradient ultracentrifugation and DNA-based ion-exchange chromatography to produce aqueous suspensions strongly enriched in armchair nanotubes. Through resonant Raman spectroscopy of the radial breathing mode phonons, we provide macroscopic and unambiguous evidence that density gradient ultracentrifugation can enrich ensemble samples in armchair nanotubes. Furthermore, using conventional, optical absorption spectroscopy in the near-infrared and visible range, we show that interband absorption in armchair nanotubes is strongly excitonic. Lastly, by examining the G-band mode in Raman spectra, we determine that observation of the broad, lower frequency (G(-)) feature is a result of resonance with non-armchair "metallic" nanotubes. These findings regarding the fundamental optical absorption and scattering processes in metallic carbon nanotubes lay the foundation for further spectroscopic studies to probe many-body physical phenomena in one dimension. PMID:23340668

  15. Determining probabilities of geologic events and processes

    Microsoft Academic Search

    R. L. Hunter; C. J. Mann; R. M. Cranwell

    1985-01-01

    The Environmental Protection Agency has recently published a probabilstic standard for releases of high-level radioactive waste from a mined geologic repository. The standard sets limits for contaminant releases with more than one change in 100 of occurring within 10,000 years, and less strict limits for releases of lower probability. The standard offers no methods for determining probabilities of geologic events

  16. Plasma-Therm Workshop: Fundamentals of Plasma Processing (Etching & Deposition)

    E-print Network

    Martin, Jan M.L.

    Plasma-Therm Workshop: Fundamentals of Plasma Processing (Etching & Deposition) Nanofabrication The workshop will focus on the fundamentals of plasma etching and deposition. Lectures will include an introduction to vacuum technology, the basics of plasma and plasma reactors and an overview of mechanisms

  17. Geologic processes on Venus: An update

    NASA Technical Reports Server (NTRS)

    Masursky, H.

    1985-01-01

    Studies of Venera 15 and 16 radar image and altimetry data and reevaluation of Pioneer Venus and earlier Venera data have greatly expanded the perception of the variety and complexity of geologic processes on Venus. PV data have discriminated four highland regions (each different in geomorphic appearance), a large upland rolling plains region, and smaller areas of lowland plains. Two highland volcanic centers were identified that may be presently active, as suggested by their geomorphologic appearance combined with positive gravity anomalies, lightning strike clusters, and a change in SO2 content in the upper atmosphere. Geochemical data obtained by the Venera landers have indicated that one upland area and nearby rolling plains are composed of volcanic rocks, probably basalts or syenites. New Venera radar images of the Ishtar Terra region show folded and/or faulted linear terrain and associated volcanic features that may have been deformed by both compressional and extensional forces. Lowland surfaces resemble the mare basaltic lava flows that fill basins on the Moon, Mars and Earth. Ubiquitous crater like forms may be of either volcanic or impact origin; the origin of similar lunar features was determined by the character of their ejecta deposits.

  18. Fundamental concepts of digital image processing

    SciTech Connect

    Twogood, R.E.

    1983-03-01

    The field of a digital-image processing has experienced dramatic growth and increasingly widespread applicability in recent years. Fortunately, advances in computer technology have kept pace with the rapid growth in volume of image data in these and other applications. Digital image processing has become economical in many fields of research and in industrial and military applications. While each application has requirements unique from the others, all are concerned with faster, cheaper, more accurate, and more extensive computation. The trend is toward real-time and interactive operations, where the user of the system obtains preliminary results within a short enough time that the next decision can be made by the human processor without loss of concentration on the task at hand. An example of this is the obtaining of two-dimensional (2-D) computer-aided tomography (CAT) images. A medical decision might be made while the patient is still under observation rather than days later.

  19. Fundamental kinetic modeling of the catalytic reforming process

    E-print Network

    Sotelo-Boyas, Rogelio

    2007-04-25

    In this work, a fundamental kinetic model for the catalytic reforming process has been developed. The complex network of elementary steps and molecular reactions occurring in catalytic reforming has been generated through a computer algorithm...

  20. THE WORLD OF QUANTUM NOISE AND THE FUNDAMENTAL OUTPUT PROCESS

    E-print Network

    Belavkin, Viacheslav P.

    THE WORLD OF QUANTUM NOISE AND THE FUNDAMENTAL OUTPUT PROCESS V. P. BELAVKIN, O. HIROTA, AND R. It includes KMS processes in wide sense like the equilibrium ...nite temperature quantum noise given process which is identical to the noise in the in...nite temperature limit, and ipping with the noise

  1. The Moon: Keystone to Understanding Planetary Geological Processes and History

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Extensive and intensive exploration of the Earth's Moon by astronauts and an international array of automated spacecraft has provided an unequaled data set that has provided deep insight into geology, geochemistry, mineralogy, petrology, chronology, geophysics and internal structure. This level of insight is unequaled except for Earth. Analysis of these data sets over the last 35 years has proven fundamental to understanding planetary surface processes and evolution, and is essential to linking surface processes with internal and thermal evolution. Much of the understanding that we presently have of other terrestrial planets and outer planet satellites derives from the foundation of these data. On the basis of these data, the Moon is a laboratory for understanding of planetary processes and a keystone for providing evolutionary perspective. Important comparative planetology issues being addressed by lunar studies include impact cratering, magmatic activity and tectonism. Future planetary exploration plans should keep in mind the importance of further lunar exploration in continuing to build solid underpinnings in this keystone to planetary evolution. Examples of these insights and applications to other planets are cited.

  2. A fundamental discussion of what triggers localized deformation in geological materials

    NASA Astrophysics Data System (ADS)

    Peters, Max; Paesold, Martin; Poulet, Thomas; Herwegh, Marco; Regenauer-Lieb, Klaus; Veveakis, Manolis

    2015-04-01

    Discontinuous or localized structures are often marked by the transition from a homogeneously deforming into a highly localized mode. This transition has extensively been described in ductile shear zones, folding and pinch-and-swell boudinage, in natural examples, rock deformation experiments and numerical simulations, at various scales. It is conventionally assumed that ductile instabilities, which act as triggers for localized deformation, exclusively arise from structural heterogeneities, i.e. geometric interactions or material imperfections. However, Hansen et al. (2012) concluded from recent laboratory experiments that localized deformation might arise out of steady-state conditions, where the size of initial perturbations was either insufficiently large to trigger localization, or these heterogeneities were simply negligible at the scale of observation. We therefore propose the existence of a principal localization phenomenon, which is based on the material-specific rate-dependency of deformation at elevated temperatures. The concept of strain localization out of a mechanical steady state in a homogeneous material at a critical material parameter and/or deformation rate has previously been discussed for engineering materials (Gruntfest, 1963) and frictional faults (Veveakis et al., 2010). We expand this theory to visco-plastic carbonate rocks, considering deformation conditions and mechanisms encountered in naturally deformed rocks. In the numerical simulation, we implement a grain-size evolution based on the Paleowattmeter scaling relationship of Austin & Evans (2007), which takes both grain size sensitive (diffusion) and insensitive (dislocation) creep combined with grain growth into account (Herwegh et al., 2014). Based on constant strain rate simulations carried out under isothermal boundary conditions, we explore the parameter space in order to obtain the criteria for localization. We determine the criteria for the onset of localization, i.e. the critical amount of dissipative work translated into heat over the diffusive capacity of the system by an instability study designed for such materials (Gruntfest, 1963). With respect to our numerical experiments, this critical parameter determines the timing when the entire amount of deformation energy translated into heat cannot be diffusively transported out of the system anymore. The resulting local temperature rise then induces strain localization. In contrast to classical shear heating scenarios with (catastrophic) thermal runaways, temperature variations of less than 1 K are sufficient for this localization mode to occur due to the balance between heat producing (e.g. dislocation creep) and consuming (grain growth) processes in the present setup. We demonstrate that this rise in latent heat is sufficient to provoke grain growth, operating as an endothermic reaction, stabilizing the simulated localized structure in turn. Various localized ductile structures, such as folded or boudinaged layers, can therefore be placed at the same material failure mode due to fundamental energy bifurcations triggered by dissipative work out of homogeneous state. Finally, we will discuss situations, in which structural heterogeneities are considered negligible and where the energy theory described here plays an underlying role by means of a comparison between numerical experiments and natural examples. REFERENCES Austin, N. and Evans, B. (2007). Paleowattmeters: A scaling relation for dynamically recrystallized grain size. Geology, 35. Gruntfest, I.J. (1963). Thermal feedback in liquid flow, plane shear at constant stress. Transactions of the Society of Rheology, 7. Hansen, L.N. and Zimmermann, M.E. and Dillman, A.M. and Kohlstedt, D.L (2012). Strain localization in olivine aggregates at high temperature: a laboratory comparison of constant-strain-rate and constant-stress boundary conditions. Earth and Planetary Science Letters, 333-334. Herwegh, M., Poulet, T., Karrech, A. and Regenauer-Lieb, K. (2014). From transient to steady state deformation and grain size: A thermodynamic

  3. The Behaviour of Selenium in Geological Processes

    Microsoft Academic Search

    E. P. Malisa

    2001-01-01

    Selenium contents were analyzed from a total of 244 soil samples collected over different rock types at a sampling density of one sample per 4?km2 around Geita gold mining areas, Northwestern Tanzania. Comparisons using literature survey contents of selenium in geological materials and some implications on the selenium in soils are compiled and discussed. Most selenium occurs as simple selenides

  4. Business process simulation: a fundamental step supporting process centered management

    Microsoft Academic Search

    Marc Aguilar; Tankred Rautert; A. J. G. Pater

    1999-01-01

    Business processes are increasingly recognised as the key to competitive survival. The important opportunities inherent to this invisible economic asset are the foundations of process-centred management. Simulation of business processes creates added value in understanding, analysing and designing processes by introducing dynamic aspects. It provides decision support by anticipation of future changes in process design and improves understanding of processes.

  5. Business process simulation: a fundamental step supporting process centered management

    Microsoft Academic Search

    Marc Aguilar; Tankred Rautert; Alexander J. G. Pater

    1999-01-01

    Business processes are increasingly recognised as the key to competitive survival. The important opportunities inherent to this invisible economic asset are the foundations of process centred management. Simulation of business processes creates added value in understanding, analysing, and designing processes by introducing dynamic aspects. It provides decision support by anticipation of future changes in process design and improves understanding of

  6. Abstracts for the Planetary Geology Field Conference on Aeolian Processes

    NASA Technical Reports Server (NTRS)

    Greeley, R. (editor); Black, D. (editor)

    1978-01-01

    The Planetary Geology Field Conference on Aeolian Processes was organized at the request of the Planetary Geology Program office of the National Aeronautics and Space Administration to bring together geologists working on aeolian problems on earth and planetologists concerned with similar problems on the planets. Abstracts of papers presented at the conference are arranged herein by alphabetical order of the senior author. Papers fall into three broad categories: (1) Viking Orbiter and Viking Lander results on aeolian processes and/or landforms on Mars, (2) laboratory results on studies of aeolian processes, and (3) photogeology and field studies of aeolian processes on Earth.

  7. Investigating the Fundamental Scientific Issues Affecting the Long-term Geologic Storage of Carbon Dioxide

    SciTech Connect

    Spangler, Lee; Cunningham, Alfred; Barnhart, Elliot; Lageson, David; Nall, Anita; Dobeck, Laura; Repasky, Kevin; Shaw, Joseph; Nugent, Paul; Johnson, Jennifer; Hogan, Justin; Codd, Sarah; Bray, Joshua; Prather, Cody; McGrail, B.; Oldenburg, Curtis; Wagoner, Jeff; Pawar, Rajesh

    2014-09-30

    The Zero Emissions Research and Technology (ZERT) collaborative was formed to address basic science and engineering knowledge gaps relevant to geologic carbon sequestration. The original funding round of ZERT (ZERT I) identified and addressed many of these gaps. ZERT II has focused on specific science and technology areas identified in ZERT I that showed strong promise and needed greater effort to fully develop. Specific focal areas of ZERT II included: ? Continued use of the unique ZERT field site to test and prove detection technologies and methods developed by Montana State University, Stanford, University of Texas, several private sector companies, and others. Additionally, transport in the near surface was modelled. ? Further development of near-surface detection technologies that cover moderate area at relatively low cost (fiber sensors and compact infrared imagers). ? Investigation of analogs for escape mechanisms including characterization of impact of CO2 and deeper brine on groundwater quality at a natural analog site in Chimayo, NM and characterization of fracture systems exposed in outcrops in the northern Rockies. ? Further investigation of biofilms and biomineralization for mitigation of small aperture leaks focusing on fundamental studies of rates that would allow engineered control of deposition in the subsurface. ? Development of magnetic resonance techniques to perform muti-phase fluid measurements in rock cores. ? Laboratory investigation of hysteretic relative permeability and its effect on residual gas trapping in large-scale reservoir simulations. ? Further development of computational tools including a new version (V2) of the LBNL reactive geochemical transport simulator, TOUGHREACT, extension of the coupled flow and stress simulation capabilities in LANL’s FEHM simulator and an online gas-mixtureproperty estimation tool, WebGasEOS Many of these efforts have resulted in technologies that are being utilized in other field tests or demonstration projects.

  8. Geology of the Icy Galilean Satellites: Understanding Crustal Processes and Geologic Histories Through the JIMO Mission

    NASA Technical Reports Server (NTRS)

    Figueredo, P. H.; Tanaka, K.; Senske, D.; Greeley, R.

    2003-01-01

    Knowledge of the geology, style and time history of crustal processes on the icy Galilean satellites is necessary to understanding how these bodies formed and evolved. Data from the Galileo mission have provided a basis for detailed geologic and geo- physical analysis. Due to constrained downlink, Galileo Solid State Imaging (SSI) data consisted of global coverage at a -1 km/pixel ground sampling and representative, widely spaced regional maps at -200 m/pixel. These two data sets provide a general means to extrapolate units identified at higher resolution to lower resolution data. A sampling of key sites at much higher resolution (10s of m/pixel) allows evaluation of processes on local scales. We are currently producing the first global geological map of Europa using Galileo global and regional-scale data. This work is demonstrating the necessity and utility of planet-wide contiguous image coverage at global, regional, and local scales.

  9. Using Springs to Study Groundwater Flow and Active Geologic Processes

    Microsoft Academic Search

    Michael Manga

    2001-01-01

    Spring water provides a unique opportunity to study a range of subsurface processes in regions with few boreholes or wells. However, because springs integrate the signal of geological and hydrological processes over large spatial areas and long periods of time, they are an indirect source of information. This review illustrates a variety of techniques and approaches that are used to

  10. Geology

    SciTech Connect

    Reidel, Stephen P.

    2008-01-17

    This chapter summarizes the geology of the single-shell tank (SST) farms in the context of the region’s geologic history. This chapter is based on the information in the geology data package for the SST waste management areas and SST RFI Appendix E, which builds upon previous reports on the tank farm geology and Integrated Disposal Facility geology with information available after those reports were published.

  11. Simulation and Processing Seismic Data in Complex Geological Models

    NASA Astrophysics Data System (ADS)

    Forestieri da Gama Rodrigues, S.; Moreira Lupinacci, W.; Martins de Assis, C. A.

    2014-12-01

    Seismic simulations in complex geological models are interesting to verify some limitations of seismic data. In this project, different geological models were designed to analyze some difficulties encountered in the interpretation of seismic data. Another idea is these data become available for LENEP/UENF students to test new tools to assist in seismic data processing. The geological models were created considering some characteristics found in oil exploration. We simulated geological medium with volcanic intrusions, salt domes, fault, pinch out and layers more distante from surface (Kanao, 2012). We used the software Tesseral Pro to simulate the seismic acquisitions. The acquisition geometries simulated were of the type common offset, end-on and split-spread. (Figure 1) Data acquired with constant offset require less processing routines. The processing flow used with tools available in Seismic Unix package (for more details, see Pennington et al., 2005) was geometric spreading correction, deconvolution, attenuation correction and post-stack depth migration. In processing of the data acquired with end-on and split-spread geometries, we included velocity analysis and NMO correction routines. Although we analyze synthetic data and carefully applied each processing routine, we can observe some limitations of the seismic reflection in imaging thin layers, great surface depth layers, layers with low impedance contrast and faults.

  12. Geology and Geophysics of Venus: Implications for Magmatic Processes

    E-print Network

    Treiman, Allan H.

    Geology and Geophysics of Venus: Implications for Magmatic Processes Walter S. Kiefer Lunar and Planetary Institute Venus Geochemistry Workshop Feb. 26, 2009 #12;#12;Basaltic Volcanism on Venus #12 decompression melting in plume head near base of lithosphere · Venus: Beta Regio, Atla Regio · Earth: Hawaii

  13. The world of quantum noise and the fundamental output process

    E-print Network

    V. P. Belavkin; O. Hirota; R. Hudson

    2005-10-04

    A stationary theory of quantum stochastic processes of second order is outlined. It includes KMS processes in wide sense like the equilibrium finite temperature quantum noise given by the Planck's spectral formula. It is shown that for each stationary noise there exists a natural output process output process which is identical to the noise in the infinite temperature limit, and flipping with the noise if the time is reversed at finite temperature. A canonical Hilbert space representation of the quantum noise and the fundamental output process is established and a decomposition of their spectra is found. A brief explanation of quantum stochastic integration with respect to the input-output processes is given using only correlation functions. This provides a mathematical foundation for linear stationary filtering transformations of quantum stochastic processes. It is proved that the colored quantum stationary noise and its time-reversed version can be obtained in the second order theory by a linear nonadapted filtering of the standard vacuum noise uniquely defined by the canonical creation and annihilation operators on the spectrum of the input-output pair.

  14. Fundamental Science Tools for Geologic Carbon Sequestration and Mineral Carbonation Chemistry: In Situ Magic Angle Spinning (MAS) Nuclear Magnetic Resonance

    NASA Astrophysics Data System (ADS)

    Hoyt, D. W.; Turcu, R. V.; Sears, J. A.; Rosso, K. M.; Burton, S. D.; Kwak, J.; Felmy, A. R.; Hu, J.

    2010-12-01

    GCS is one of the most promising ways of mitigating atmospheric greenhouse gases. Mineral carbonation reactions are potentially important to the long-term sealing effectiveness of caprock but remain poorly predictable, particularly reactions occurring in low-water supercritical CO2(scCO2)-dominated environments where the chemistry has not been adequately explored. In situ probes that provide molecular-level information is desirable for investigating mechanisms and rates of GCS mineral carbonation reactions. MAS-NMR is a powerful tool for obtaining detailed molecular structure and dynamics information of a system regardless whether the system is in a solid, a liquid, a gaseous, or a supercritical state, or a mixture thereof. However, MAS NMR under scCO2 conditions has never been realized due to the tremendous technical difficulties of achieving and maintaining high pressure within a fast spinning MAS rotor. In this work, we report development of a unique high pressure MAS NMR capability, and its application to mineral carbonation chemistry in scCO2 under geologically relevant temperatures and pressures. Our high pressure MAS rotor has successfully maintained scCO2 conditions with minimal leakage over a period of 72 hours. Mineral carbonation reactions of a model magnesium silicate (forsterite) reacted with 96 bars scCO2 containing varying amounts of H2O (both below and above saturation of the scCO2) were investigated at 50?C. Figure 1 shows typical in situ 13C MAS NMR spectra demonstrating that the peaks corresponding to the reactants, intermediates, and the magnesium carbonation products are all observed in a single spectrum. For example, the scCO2 peak is located at 126.1 ppm. Reaction intermediates include the aqueous species HCO3-(160 ppm), partially hydrated/hydroxylated magnesium carbonates(166-168 ppm), and can easily be distinguished from final product magnesite(170 ppm). The new capability and this model mineral carbonation process will be overviewed in light of fundamental geochemical science needs for GCS implementation. Figure 1. 13C MAS NMR spectra of forsterite exposed to scCO2 300% saturated with water at 96 bars and 50°C. MAS rate=2.1 kHz.

  15. Giant ore deposits formed by optimal alignments and combinations of geological processes

    NASA Astrophysics Data System (ADS)

    Richards, Jeremy P.

    2013-11-01

    Giant ore deposits contain anomalously large quantities of metal and are priority targets for mineral exploration companies. It is debated whether these giant deposits have a unique mode of formation. Alternatively they may simply represent the extreme end of a spectrum of deposit sizes, formed by an optimum coincidence of common geological processes to build unusually large accumulations of metal. If formed by unique processes, the occurrence of giant ore deposits may be difficult to predict. Conversely, if formed by common processes, understanding the mechanisms that lead to optimum circumstances for giant metal deposits could help with exploration. A review of several giant porphyry copper-molybdenum-gold and epithermal gold-silver deposits reveals that many have characteristics consistent with formation during the optimization of normal ore-forming processes. In several cases, the large size of the deposit reflects specific factors, such as distinct tectonic configurations, reactive host rocks or focused fluid flow, that are not unusual by themselves but have helped to enhance the overall process. Thus, I suggest that effective exploration for giant deposits should seek distinct conditions within fundamentally prospective geological settings that might lead to enhanced ore-forming processes.

  16. Exact solution of the zero-range process: fundamental diagram of the corresponding exclusion process

    Microsoft Academic Search

    Masahiro Kanai

    2007-01-01

    In this paper, we propose a general way of computing expectation values in the zero-range process (ZRP), using an exact form of the partition function. As an example, we provide the fundamental diagram (the flux-density plot) of the asymmetric exclusion process corresponding to the ZRP. We express the partition function for the steady state by the Lauricella hypergeometric function, and

  17. Magnetic Reconnection: A Fundamental Process in Space Plasmas

    NASA Technical Reports Server (NTRS)

    Hesse, Michael

    2010-01-01

    For many years, collisionless magnetic reconnect ion has been recognized as a fundamental process, which facilitates plasma transport and energy release in systems ranging from the astrophysical plasmas to magnetospheres and even laboratory plasma. Beginning with work addressing solar dynamics, it has been understood that reconnection is essential to explain solar eruptions, the interaction of the solar wind with the magnetosphere, and the dynamics of the magnetosphere. Accordingly, the process of magnetic reconnection has been and remains a prime target for space-based and laboratory studies, as well as for theoretical research. Much progress has been made throughout the years, beginning with indirect verifications by studies of processes enabled by reconnection, such as Coronal Mass Ejections, Flux Transfer Events, and Plasmoids. Theoretical advances have accompanied these observations, moving knowledge beyond the Sweet-Parker theory to the recognition that other, collisionless, effects are available and likely to support much faster reconnect ion rates. At the present time we are therefore near a break-through in our understanding of how collisionless reconnect ion works. Theory and modeling have advanced to the point that two competing theories are considered leading candidates for explaining the microphysics of this process. Both theories predict very small spatial and temporal scales. which are. to date, inaccessible to space-based or laboratory measurements. The need to understand magnetic reconnect ion has led NASA to begin the implementation of a tailored mission, Magnetospheric MultiScale (MMS), a four spacecraft cluster equipped to resolve all relevant spatial and temporal scales. In this presentation, we present an overview of current knowledge as well as an outlook towards measurements provided by MMS.

  18. Modeling the fundamental characteristics and processes of the spacecraft functioning

    NASA Technical Reports Server (NTRS)

    Bazhenov, V. I.; Osin, M. I.; Zakharov, Y. V.

    1986-01-01

    The fundamental aspects of modeling of spacecraft characteristics by using computing means are considered. Particular attention is devoted to the design studies, the description of physical appearance of the spacecraft, and simulated modeling of spacecraft systems. The fundamental questions of organizing the on-the-ground spacecraft testing and the methods of mathematical modeling were presented.

  19. Fundamental studies of catalytic processing of synthetic liquids

    SciTech Connect

    Watson, P.R.

    1991-10-14

    This project revolves around understanding the fundamental processes involved in the catalytic removal of harmful oxygenated organics present in coal liquids. We are modelling the complex type of sulfided Mo catalyst proposed for these reactions with simple single crystal surfaces. These display a controlled range and number of reaction sites and can be extensively characterized by surface science techniques. We then investigate the reaction pathways for representative simple oxygenates upon these surfaces. Our previous work has shown that an important component of furan reactions on sulfided Mo surfaces are dehydrogenation reactions of adsorbed hydrocarbon fragments. The desorption of hydrogen occurs in several steps and is strongly influenced by the amounts of sulfur and carbon on the surface. In order to understand this complex behavior during this period we have performed a complete series of adsorption/desorption experiments for hydrogen (deuterium) on Mo(110) that has been prepared with varying amounts of carbon and sulfur on the surface. Hydrogen adsorption is blocked by preadsorbed sulfur with a dramatic weakening of the strength with which hydrogen is bound to the surface. Hydrogen adsorption is totally blocked by 0.5 ML of preadsorbed sulfur. 4 refs., 9 figs.

  20. Laboratory Studies of Fundamental Physics Processes in Space Astrophysical Plasmas

    NASA Astrophysics Data System (ADS)

    Yamada, Masaaki

    2003-10-01

    Despite the enormous difference in physical scales, there are striking similarities in the behavior of laboratory and space plasmas. In the recent decade, a fruitful cross fertilization has been initiated between laboratory plasma physicists and space-astrophysicists in multidisciplinary meetings. The advances in laboratory plasma physics, along with the recent surge of space astrophysical data from satellites, have made collaborative research very useful for obtaining new understanding of key space and astrophysical phenomena. The recent rapid advance of numerical simulations has played an important role to bridge laboratory data with space-astrophysical observations. Many common plasma physics mechanisms have been identified in our research fields that study plasma waves, particle acceleration, magnetic reconnection, dynamos, transport and, more generally, plasma's self-organization phenomena. For example, the magnetic reconnection phenomenon is considered to be a key process in the evolution of solar flares, in the dynamics of the earth's magnetosphere and in the formation process of stars. It is also one of the most important self-organization processes in fusion research plasmas. It is crucial for both fields to understand the basic physics of magnetic reconnection. The present talk presents examples of common plasma physics issues which are extensively investigated among laboratory and space astrophysics research. Special focus is put on magnetic self-organization phenomena [1] which include magnetic reconnection [2] and dynamos [3]. During the past decade, many "physics-issue-dedicated" laboratory experiments have been constructed to address the specified physics mechanisms of space-astrophysical phenomena. They can generate fundamental physics processes in a controlled manner and provide well-correlated data of plasma parameters simultaneously at multiple locations. This talk reviews the most recent progress of these dedicated laboratory experiments as well as comparison of the data with space astrophysical observations and numerical simulation results. The talk also covers the goals and principles of the recent new initiatives to attack the common frontier of both laboratory and space astrophysics research. [1] J.B. Taylor, Rev. Modern phys.,vol.58, 741 (1986) [2] M. Yamada, Earth Planets Space, vol.53, 539 (2001) [3] H. Ji and S. Prager, Magnetohydrodynamics, vol.38,191 (2002)

  1. Fundamental Chemical Kinetic And Thermodynamic Data For Purex Process Models

    SciTech Connect

    Taylor, R.J.; Fox, O.D.; Sarsfield, M.J.; Carrott, M.J.; Mason, C.; Woodhead, D.A.; Maher, C.J. [British Technology Centre, Nexia Solutions, Sellafield, Seascale, CA20 1PG (United Kingdom); Steele, H. [Nexia Solutions, inton House, Risley, Warrington, WA3 6AS (United Kingdom); Koltunov, V.S. [A.A. Bochvar All-Russia Institute of Inorganic Materials, VNIINM, PO Box 369, Moscow 123060 (Russian Federation)

    2007-07-01

    To support either the continued operations of current reprocessing plants or the development of future fuel processing using hydrometallurgical processes, such as Advanced Purex or UREX type flowsheets, the accurate simulation of Purex solvent extraction is required. In recent years we have developed advanced process modeling capabilities that utilize modern software platforms such as Aspen Custom Modeler and can be run in steady state and dynamic simulations. However, such advanced models of the Purex process require a wide range of fundamental data including all relevant basic chemical kinetic and thermodynamic data for the major species present in the process. This paper will summarize some of these recent process chemistry studies that underpin our simulation, design and testing of Purex solvent extraction flowsheets. Whilst much kinetic data for actinide redox reactions in nitric acid exists in the literature, the data on reactions in the diluted TBP solvent phase is much rarer. This inhibits the accurate modelization of the Purex process particularly when species show a significant extractability in to the solvent phase or when cycling between solvent and aqueous phases occurs, for example in the reductive stripping of Pu(IV) by ferrous sulfamate in the Magnox reprocessing plant. To support current oxide reprocessing, we have investigated a range of solvent phase reactions: - U(IV)+HNO{sub 3}; - U(IV)+HNO{sub 2}; - U(IV)+HNO{sub 3} (Pu catalysis); - U(IV)+HNO{sub 3} (Tc catalysis); - U(IV)+ Np(VI); - U(IV)+Np(V); - Np(IV)+HNO{sub 3}; - Np(V)+Np(V); Rate equations have been determined for all these reactions and kinetic rate constants and activation energies are now available. Specific features of these reactions in the TBP phase include the roles of water and hydrolyzed intermediates in the reaction mechanisms. In reactions involving Np(V), cation-cation complex formation, which is much more favourable in TBP than in HNO{sub 3}, also occurs and complicates the redox chemistry. Whilst some features of the redox chemistry in TBP appear similar to the corresponding reactions in aqueous HNO{sub 3}, there are notable differences in rates, the forms of the rate equations and mechanisms. Secondly, to underpin the development of advanced single cycle flowsheets using the complexant aceto-hydroxamic acid, we have also characterised in some detail its redox chemistry and solvent extraction behaviour with both Np and Pu ions. We find that simple hydroxamic acids are remarkably rapid reducing agents for Np(VI). They also reduce Pu(VI) and cause a much slower reduction of Pu(IV) through a complex mechanism involving acid hydrolysis of the ligand. AHA is a strong hydrophilic and selective complexant for the tetravalent actinide ions as evidenced by stability constant and solvent extraction data for An(IV), M(III) and U(VI) ions. This has allowed the successful design of U/Pu+Np separation flowsheets suitable for advanced fuel cycles. (authors)

  2. Fundamental studies of catalytic processing of synthetic liquids. Final report

    SciTech Connect

    Watson, P.R.

    1994-06-15

    Liquids derived from coal contain relatively high amounts of oxygenated organic compounds, mainly in the form of phenols and furans that are deleterious to the stability and quality of these liquids as fuels. Hydrodeoxygenation (HDO) using Mo/W sulfide catalysts is a promising method to accomplish this removal, but our understanding of the reactions occurring on the catalyst surface during HDO is very limited. Rather than attempting to examine the complexities of real liquids and catalysts we have adopted an approach here using model systems amenable to surface-sensitive techniques that enable us to probe in detail the fundamental processes occurring during HDO at the surfaces of well-defined model catalysts. The results of this work may lead to the development of more efficient, selective and stable catalysts. Above a S/Mo ratio of about 0.5 ML, furan does not adsorb on sulfided Mo surfaces; as the sulfur coverage is lowered increasing amounts of furan can be adsorbed. Temperature-programmed reaction spectroscopy (TPRS) reveals that C-H, C-C and C-O bond scission occurs on these surfaces. Auger spectra show characteristic changes in the nature and amount of surface carbon. Comparisons with experiments carried out with CO, H{sub 2} and alkenes show that reaction pathways include -- direct abstraction of CO at low temperatures; cracking and release of hydrogen below its normal desorption temperature; dehydrogenatin of adsorbed hydrocarbon fragments; recombination of C and O atoms and dissolution of carbon into the bulk at high temperatures. Performing the adsorption or thermal reaction in 10{sup {minus}5} torr of hydrogen does not change the mode of reaction significantly.

  3. Sanders, J. E., and Merguerian, Charles, 1994c, Glacial geology of Staten Island. The fundamental question pertaining to the Pleistocene features of the New York City

    E-print Network

    Merguerian, Charles

    Sanders, J. E., and Merguerian, Charles, 1994c, Glacial geology of Staten Island. The fundamental-moraine ridge in southern Staten Island prove that ice flowed regionally across Staten Island from NW to SE that on Staten Island are products of at least 3, possibly 4, glacial advances. We regard their ages as

  4. Techniques for determining probabilities of geologic events and processes

    SciTech Connect

    Hunter, R.L. (ed.) (Sandia National Labs., Albuquerque, NM (United States)); Mann, C.J. (ed.) (Illinois Univ., Urbana, IL (United States))

    1992-01-01

    The primary goal of this study has been to search out and evaluate existing quantitative methods for determining probabilities of events and processes in fields that seemed to be most closely related to the majority of the events considered important to long-term performance by earlier workers. These fields are thermomechanical behavior, mining engineering, hydrology, climatology, seismicity and tectonics, seismic hazard, volcanology, geochemistry, and resource exploration. Most of these events and processes can initiate, releases of the radioactive waste from a geologic repository, although geochemical processes primarily affect transport of wastes after release. The quantitative methods for determining probabilities identified here are those that have been reported in the literature, and some that could be used but have not been reported. Merits and limitations of each method have been described, and the current availability of databases adequate for determining accurate probabilities of events and processes has been appraised. A secondary goal has been to identify phenomena for which accurate probabilities cannot be determined now and areas of research that could materially improve our ability to make better probabilistic predictions in the immediate future.

  5. Techniques for determining probabilities of geologic events and processes

    SciTech Connect

    Hunter, R.L. [ed.] [Sandia National Labs., Albuquerque, NM (United States); Mann, C.J. [ed.] [Illinois Univ., Urbana, IL (United States)

    1992-10-01

    The primary goal of this study has been to search out and evaluate existing quantitative methods for determining probabilities of events and processes in fields that seemed to be most closely related to the majority of the events considered important to long-term performance by earlier workers. These fields are thermomechanical behavior, mining engineering, hydrology, climatology, seismicity and tectonics, seismic hazard, volcanology, geochemistry, and resource exploration. Most of these events and processes can initiate, releases of the radioactive waste from a geologic repository, although geochemical processes primarily affect transport of wastes after release. The quantitative methods for determining probabilities identified here are those that have been reported in the literature, and some that could be used but have not been reported. Merits and limitations of each method have been described, and the current availability of databases adequate for determining accurate probabilities of events and processes has been appraised. A secondary goal has been to identify phenomena for which accurate probabilities cannot be determined now and areas of research that could materially improve our ability to make better probabilistic predictions in the immediate future.

  6. Linking subsurface temperature and hillslope processes through geologic time

    NASA Astrophysics Data System (ADS)

    Barnhart, Katherine; Anderson, Robert

    2015-04-01

    Many periglacial hillslope processes - physical, chemical, and biological - depend on subsurface temperature and water availability. As the subsurface temperature field varies both in space and through time over many scales up to climate cycles, the dominant processes of mobile regolith production and transport and the rate at which they act will vary. These processes include the chemical weathering of minerals, cracking of rocks through frost action and tree roots, presence and impact of vegetation on soil cohesion, location and activity of burrowing and trampling animals, frost creep, and solifluction. In order to explore the interplay between these processes across a landscape over the geologic timescales on which such landscapes evolve, we explore the effects of slope, aspect, latitude, atmosphere, and time before present on the expected energy balance at the surface of the earth and the resulting subsurface temperature field. We begin by calculating top-of-atmosphere insolation at any time in the Quaternary, honoring the variations in orbit over Milankovitch timescales. We then incorporate spatial and temporal variations in incoming short-wave radiation on sub-daily timescales due to elevation, latitude, aspect, and shading. Outgoing long-wave radiation is taken to depend on the surface temperature and may be modified by allowing back-radiation from the atmosphere. We then solve for the subsurface temperature field using a numerical model that acknowledges depth-varying material properties, water content, and phase change. With these tools we target variations in regolith production and motion over the long timescales on which periglacial hillslopes evolve. We implement a basic parameterization of temperature-dependent chemical and physical weathering linked to mobile regolith generation. We incorporate multiple regolith transport processes including frost heave and creep. Our intention is not to parameterize all operative processes, but to include sufficient detail to identify how the different processes interact. We address questions that include: What governs contrasts in process rate on pole-ward vs. equator-ward slopes? Under what conditions should we expect temporal transitions between transport-limited and weathering-limited erosion? How does the legacy of past climate impact later hillslope activity?

  7. Fundamentals of Alloy Solidification Applied to Industrial Processes

    NASA Technical Reports Server (NTRS)

    1984-01-01

    Solidification processes and phenomena, segregation, porosity, gravity effects, fluid flow, undercooling, as well as processing of materials in the microgravity environment of space, now available on space shuttle flights were discussed.

  8. IDENTIFICATION AND EVALUATION OF FUNDAMENTAL TRANSPORT AND TRANSFORMATION PROCESS MODELS

    EPA Science Inventory

    Chemical fate models require explicit algorithms for computing the effects of transformation and transport processes on the spatial and temporal distribution of chemical concentrations. Transport processes in aquatic systems are driven by physical characteristics on the system an...

  9. Views: Fundamental Building Blocks in the Process of Knowledge Discovery

    Microsoft Academic Search

    Hideo Bannai; Yoshinori Tamada; Osamu Maruyama; Kenta Nakai; Satoru Miyano

    2001-01-01

    We present a novel approach to describe the knowledge dis- covery process, focusing on a generalized form of attribute called view. It is observed that the process of knowledge dis- covery can, in fact. be modeled as the design, generation, use, and evaluation of views, asserting that views are the funda- mental building blocks in the discovery process. We realize

  10. Beowulf Distributed Processing and the United States Geological Survey

    USGS Publications Warehouse

    Maddox, Brian G.

    2002-01-01

    Introduction In recent years, the United States Geological Survey's (USGS) National Mapping Discipline (NMD) has expanded its scientific and research activities. Work is being conducted in areas such as emergency response research, scientific visualization, urban prediction, and other simulation activities. Custom-produced digital data have become essential for these types of activities. High-resolution, remotely sensed datasets are also seeing increased use. Unfortunately, the NMD is also finding that it lacks the resources required to perform some of these activities. Many of these projects require large amounts of computer processing resources. Complex urban-prediction simulations, for example, involve large amounts of processor-intensive calculations on large amounts of input data. This project was undertaken to learn and understand the concepts of distributed processing. Experience was needed in developing these types of applications. The idea was that this type of technology could significantly aid the needs of the NMD scientific and research programs. Porting a numerically intensive application currently being used by an NMD science program to run in a distributed fashion would demonstrate the usefulness of this technology. There are several benefits that this type of technology can bring to the USGS's research programs. Projects can be performed that were previously impossible due to a lack of computing resources. Other projects can be performed on a larger scale than previously possible. For example, distributed processing can enable urban dynamics research to perform simulations on larger areas without making huge sacrifices in resolution. The processing can also be done in a more reasonable amount of time than with traditional single-threaded methods (a scaled version of Chester County, Pennsylvania, took about fifty days to finish its first calibration phase with a single-threaded program). This paper has several goals regarding distributed processing technology. It will describe the benefits of the technology. Real data about a distributed application will be presented as an example of the benefits that this technology can bring to USGS scientific programs. Finally, some of the issues with distributed processing that relate to USGS work will be discussed.

  11. Fundamental kinetic modeling of the catalytic reforming process 

    E-print Network

    Sotelo-Boyas, Rogelio

    2007-04-25

    industrial conditions for both axial and radial flow fixed bed reactors. The influence of the main process variables on the octane number and reformate volume was investigated and optimal conditions were obtained. Additional aspects studied with the kinetic...

  12. Exclusive Processes and the Fundamental Structure of Hadrons

    DOE PAGESBeta

    Brodsky, Stanley J.

    2015-01-20

    I review the historical development of QCD predictions for exclusive hadronic processes, beginning with constituent counting rules and the quark interchange mechanism, phenomena which gave early validation for the quark structure of hadrons. The subsequent development of pQCD factorization theorems for hard exclusive amplitudes and the development of evolution equations for the hadron distribution amplitudes provided a rigorous framework for calculating hadronic form factors and hard scattering exclusive scattering processes at high momentum transfer. I also give a brief introduction to the field of "light-front holography" and the insights it brings to quark confinement, the behavior of the QCD couplingmore »in the nonperturbative domain, as well as hadron spectroscopy and the dynamics of exclusive processes.« less

  13. Processes of lunar crater degradation - Changes in style with geologic time

    NASA Technical Reports Server (NTRS)

    Head, J. W.

    1975-01-01

    Relative age schemes of crater degradation are calibrated to radiometric dates obtained from lunar samples, changes in morphologic features are analyzed, and the style and rate of lunar surface degradation processes are modeled in relation to lunar geologic time. A comparison of radiometric age scales and the relative degradation of morphologic features for craters larger than about 5 km in diameter shows that crater degradation can be divided into two periods: Period I, prior to about 3.9 billion years ago and characterized by a high meteoritic influx rate and the formation of large multiringed basins, and Period II, from about 3.9 billion years ago to the present and characterized by a much lower influx rate and a lack of large multiringed basins. Diagnostic features for determining the relative ages of craters are described, and crater modification processes are considered, including primary impacts, lateral sedimentation, proximity weathering, landslides, and tectonism. It is suggested that the fundamental degradation of early Martian craters may be associated with erosional and depositional processes related to the intense bombardment characteristics of Period I.

  14. Hydro-geological process chain for building a flood scenario

    NASA Astrophysics Data System (ADS)

    Longoni, Laura; Brambilla, Davide; Papini, Monica; Ivanov, Vladislav; Radice, Alessio

    2015-04-01

    Flash-flood events in mountain environments are often related to the transport of large amounts of sediment from the slopes through the stream network. As a consequence, significant morphological changes may occur in rivers during a single, short-duration event, with possibly significant effect on the water elevation. An appropriate hazard evaluation would therefore require the thorough modelling of the flood-related phenomena and of their interconnection. In this context, this work is focused on an attempt of integrated modelling of event-scale water and sediment transport processes for a reference case-study of the Mallero basin in the Italian Alps. The area of the catchments is about 320 square km, the main stream being almost 25 km long and having slopes in the range from 1 to 40 %. A town (Sondrio) is present at the downstream end of the river. In 1987, Sondrio was at risk of inundation due to a combined effect of relatively high discharge and aggradation of the river bed up to 5 m (almost equal to the bankfull depth in the in-town reach). A 100-year flood scenario was produced including (i) a sediment supply model, (ii) a one-dimensional, hydro-morphologic model of the river bed evolution, and (iii) an estimation of the outflowing discharge at river sections where the bank elevation was exceeded by water. Rainfall-runoff transformation was not included into the modelling chain as the 100-year water hydrograph was already available from previous studies. For the sediment production model, a downscaling in time of the Gavrilovic equation was attempted using rainfall estimation from depth-duration-frequency curves, which furnished values in reasonable agreement with some available data. The hydro-morphologic model, based on the Saint-Venant and Exner equations, was preliminarily calibrated against data for bed aggradation measured in 1987. A point of separation was chosen at an appropriate location in the basin, and the sediment yield estimated upstream of this point was used as an upstream boundary condition for the hydro-morphologic model, under a simplifying hypothesis of process separation that would be later discussed. Particular attention is indeed necessary when dealing with the interface between the geologic and hydraulic processes, where models lack consistency between their respective spatial and temporal scales. Uncertainty was dealt with by sensitivity analysis. Modelling results are discussed in terms of the validity of the separate models as well as of the approach for their integration. In general, the importance of antecedent conditions of the river reach is highlighted, which suggests to apply long-term analysis prior to short-term modelling of the event.

  15. Geologic mapping of the Ladakh Himalaya by computer processing of Landsat data

    NASA Technical Reports Server (NTRS)

    Francica, J. R.; Birnie, R. W.; Johnson, G. D.

    1980-01-01

    Computer processed Landsat digital data and field studies have been integrated to make a geologic map of the Indus Suture in the Ladakh Himalaya. This coordinated approach has been successful at locating and identifying the areal extent of the major rock bodies in a 2500 square kilometer area, much of which is inaccessable for conventional field geologic studies.

  16. Spontaneous Roughening: Fundamental Limits in Si(100) Halogen Etch Processing

    NASA Astrophysics Data System (ADS)

    Herrmann, Cari F.; Chen, Dongxue; Boland, John J.

    2002-08-01

    A dynamical scanning tunneling microscopy and density functional theory study of the thermodynamic stability of halogen-terminated Si(100) surfaces is presented. Significant steric repulsions are shown to exist on all halogen-terminated Si(100) surfaces. These repulsions are the driving force for a roughening phenomenon, which is favored for all halogens except fluorine. Since roughening is an intrinsic property of these surfaces, it sets a lower bound on the atomic scale perfection that can be achieved using halogen etch processing.

  17. Tracking the Neuro-Cognitive Processes Fundamental to Reading Guest Lecture by Phillip Holcomb

    E-print Network

    Stanford, Kyle

    Tracking the Neuro-Cognitive Processes Fundamental to Reading Guest Lecture by Phillip Holcomb Professor, Co-Director of NeuroCognition Laboratory of the neuro-cognitive approach for providing a comprehensive understanding of the brain

  18. Fundamental processes in the interacting boson model: 0{nu}{beta}{beta} decay

    SciTech Connect

    Iachello, F. [Center for Theoretical Physics, Sloane Physics Laboratory, Yale University, New Haven, CT 06520-8120 (United States); Barea, J. [Departamento de Fisica, Universidad de Concepcion, Casilla 160-C, Concepcion (Chile)

    2011-05-06

    A program to calculate nuclear matrix elements for fundamental processes in the interacting boson model has been initiated. Results for the nuclear matrix elements in neutrinoless double beta decay 0{nu}{beta}{beta} are presented.

  19. Fundamental study on electrolyte recycle process by phosphates conversion technique

    SciTech Connect

    Amamoto, Ippei; Myochin, Munetaka [Japan Atomic Energy Agency, 4-33 Muramatsu, Tokai-mura, Naka-gun, Ibaraki Pref. 319-1109 (Japan); Kofuji, Hirohide [Japan Atomic Energy Agency, 4-33 Muramatsu, Tokai-mura, Naka-gun, Ibaraki Pref. 319-1109 (Japan)]|[Dept. of Nuclear Engineering and Management, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656 (Japan); Terai, Takayuki [Dept. of Nuclear Engineering and Management, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656 (Japan)

    2007-07-01

    Fission product elements (FP) such as alkali metals, alkaline earth metals and rare-earth elements (REE) are apt to remain in the eutectic medium used in pyro-reprocessing even after treatment at the pyro-contactor step. It is desirable to have the spent electrolyte purified for recycling which in turn, could lead to the reduction of high-level radioactive wastes. This study is carried out to evaluate the feasibility of the electrolyte recycle process by the phosphates conversion technique. First of all, a reference block flow diagram, which consists of three steps, i.e., 'Spent Electrolyte Regeneration Step', 'Phosphates Conversion Step', and 'Phosphates Immobilization Step', was designed based on known developmental results from literature. Subsequently, evaluation was undertaken by comparison with conventional relevant experimental and theoretical analysis results after gathering the essential basic data for thermodynamic calculation. The obtained computational value was then reflected to establish the preliminary conceptual flow diagram which would facilitate the next discussion and experiment for the realization of this process. (authors)

  20. Digitizing rocks standardizing the geological description process using workstations

    SciTech Connect

    Saunders, M.R. (EXLOG (Services), Windsor, Berkshire (United Kingdom)); Shields, J.A. (EXLOG North Sea, Aberdeen (United Kingdom)); Taylor, M.R. (EXLOG, Inc., Houston, TX (United States))

    1993-09-01

    The preservation of geological knowledge in a standardized digital form presents a challenge. Data sources, inherently fuzzy, range in scale from the macroscopic (e.g., outcrop) through the mesoscopic (e.g., hand-specimen) core and sidewall core, to the microscopic (e.g., drill cuttings, thin sections, and microfossils). Each scale change results in increased heterogeneity and potentially contradictory data and the providers of such data may vary in experience level. To address these issues with respect to cores and drill cuttings, a geological description workstation has been developed and is undergoing field trials. Over 1000 carefully defined geological attributes are currently available within a depth-indexed, relational database. Attributes are stored in digital form, allowing multiple users to select familiar usage (e.g., diabase vs. dolerite). Data can be entered in one language and retrieved in other languages. The database structure allow groupings of similar elements (e.g., rhyolites in acidic, igneous or volcanics subgroups or the igneous rock group) permitting different uses to analyze details appropriate to the scale of the usage. Data entry uses a graphical user interface, allowing the geologist to make quick, logical selections in a standardized or custom-built format with extensive menus, on-screen graphics and help screens available. Description ranges are permissible. Entries for lithology, petrology, structures (sedimentary, organic and deformational), reservoir characteristics (porosity and hydrocarbon shows), and macrofossils are available. Sampling points for thin sections, core analysis, geochemistry, or micropaleontology studies are also recorded. Using digital data storage, geological logs using graphical, alphanumeric and symbolic depictions are possible. Data can be integrated with drilling and mud gas data, MWD and wireline data and off well-site analyses to produced composite formation evaluation logs and interpretational crossplots.

  1. Fundamental process and system design issues in CO 2 vapor compression systems

    Microsoft Academic Search

    Man-Hoe Kim; Jostein Pettersen; Clark W. Bullard

    2004-01-01

    This paper presents recent developments and state of the art for transcritical CO2 cycle technology in various refrigeration, air-conditioning and heat pump applications. The focus will be on fundamental process and system design issues, including discussions of properties and characteristics of CO2, cycle fundamentals, methods of high-side pressure control, thermodynamic losses, cycle modifications, component\\/system design, safety factors, and promising application

  2. The lively Aysén fjord, Chile: Records of multiple geological processes

    NASA Astrophysics Data System (ADS)

    Lastras, Galderic; Amblas, David; Calafat, Antoni; Canals, Miquel; Frigola, Jaime; Hermanns, Reginald L.; Lafuerza, Sara; Longva, Oddvar; Micallef, Aaron; Sepślveda, Sergio A.; Vargas, Gabriel; Azpiroz, Marķa; Bascuńįn, Ignacio; Duhart, Paul; Iglesias, Olaia; Kempf, Philipp; Rayo, Xavier

    2014-05-01

    The Aysén fjord is a 65 km long, east-west oriented fjord in Chilean Patagonia, located approximately at 45.4ŗS and 73.2ŗW, with a maximum water depth of 345 m. The fjord receives at present the riverine input of Aysén, Pescado, Condor and Cuervo rivers, which drain the surrounding up to 2000 m high Patagonian Andes. The fjord is crossed by a number of faults associated to the seismically active Liquińe-Ofqui Fault Zone, a major trench parallel intra-arc fault system. After a four-month period of moderate seismicity, an Mw 6.2 earthquake on 21 April 2007 triggered dozens of subaerial landslides along the fjord flanks. Some of the landslides reached the fjord water mass, generating a series of tsunami-like displacement waves that impacted the adjacent coastlines with 3-12 m, locally over 50 m high run-ups, causing ten fatalities and severe damage to salmon farms. The research cruise DETSUFA on board BIO Hespérides in March 2013 mapped the submerged morphology of the fjord and gathered air-gun seismic profiles and sediment gravity cores in order to characterise the footprint of the landslides in the fjord floor. Very-high resolution multibeam bathymetry (4 m cell size) clearly shows the deformation structures created by the landslides in the inner fjord. The landslides descended and accelerated down the submerged fjord flanks, and reached the fjord floor at approx. 200 m water depth generating large, 1 to 10 m deep impact depressions. Sediment removed from these depressions moved radially and piled up in deformation rings formed by compressional ridges 10-15 m in height, block fields and a narrow frontal depression. Up to six >1.5 square km of these structures can be identified in the fjord. In addition, the DETSUFA survey extended beyond the SE-NW-oriented inner fjord past the Cuervo Ridge, located in front of the Cuervo river delta. The ridge, previously interpreted as a volcanic transverse structure, has most probably acted as a limit for grounding ice in the past, as suggested by the presence of melt-water channels lateral to the ridge. Beyond the ridge, the fjord smoothens and deepens to more than 330 m forming an enclosed basin before turning SW. There, it shallows back across a field of streamlined submerged hills of glacial origin. The external Aysén fjord, before joining to Canal Costa and Canal Moraleda, is characterized by three volcanic cones, one of them forming Isla Colorada - which also acted as a glacial limit - and the other two totally submerged and previously unknown. The largest one is 160 m high, 1.3 km in diameter and tops at 67 m water depth. This data set illustrates the complex interaction between fluvial, glacial, tectonic, volcanic and gravity processes and evidences the recent lively geological history of Aysén fjord.

  3. National Institutes of Health Fundamentals of the NIH and the NIH Grants Process

    E-print Network

    Thomas, Andrew

    National Institutes of Health Fundamentals of the NIH and the NIH Grants Process for University Office of Extramural Research, NIH; and NIH Program Manager for Electronic Receipt of Grant Applications Learn about the NIH and its basic grants process, including: · mission and organization of the NIH

  4. The consideration of geological uncertainty in the siting process for a Geological Disposal Facility for radioactive waste

    NASA Astrophysics Data System (ADS)

    Mathers, Steve; McEvoy, Fiona; Shaw, Richard

    2015-04-01

    Any decision about the site of a Geological Disposal Facility at depth for medium to high level radioactive waste is based on a safety case which in turn is based on an understanding of the geological environment which enables, for example, understanding groundwater flows and groundwater chemical composition. Because the information on which geological understanding is based cannot be fully understood, it is important to ensure that: i. Inferences are made from data in a way that is consistent with the data. ii. The uncertainty in the inferred information is described, quantitatively where this is appropriate. Despite these uncertainties decisions can and must be made, and so the implications of the uncertainty need to be understood and quantified. To achieve this it is important to ensure that: i. An understanding of how error propagates in all models and decision tools. Information which is collected to support the decision-making process may be used as input into models of various kinds to generate further information. For example, a process model may be used to predict groundwater flows, so uncertainty in the properties which are input to the model (e.g. on rock porosity and structure) will give rise to uncertainty in the model predictions. Understanding how this happens is called the analysis of error propagation. It is important that there is an understanding of how error propagates in all models and decision tools, and therefore knowledge of how much uncertainty remains in the process at any stage. As successive phases of data collection take place the analysis of error propagation shows how the uncertainty in key model outputs is gradually reduced. ii. The implications of all uncertainties can be traced through the process. A clear analysis of the decision-making process is necessary so that the implications of all uncertainties can be traced through the process. This means that, when a final decision is made, one can state with a high level of confidence that site conditions, while not known exactly, fall within an acceptable range.

  5. Recent Advances in Shannon Sampling Theory --Fundamental Limits for Digital Signal Processing

    E-print Network

    Müller, Ralf R.

    Vladimir A. Kotel'nikov Claude E. Shannon k=- f(k) sin((t - k)) (t - k) Recent Advances in Shannon, another baby of Claude Shannon." R. P. Feynman, Feynman Lectures on Computation, A. J. Hey and R. W. AllenRecent Advances in Shannon Sampling Theory -- Fundamental Limits for Digital Signal Processing

  6. Subdivision as a Fundamental Building Block of Digital Geometry Processing Algorithms

    E-print Network

    Desbrun, Mathieu

    laser range scanners, 3D photography systems based on stereo matching, contact digitizers, as wellØoder Caltech 1 Introduction Multi media data types such as digital sound, images, and video are now ubiquitousSubdivision as a Fundamental Building Block of Digital Geometry Processing Algorithms Peter Schr

  7. 156:203 Fundamentals of Dynamic Cell Processes MWF 11:30 am

    E-print Network

    :30-12:20 pm Building: Bowen Science Building, Spivey Auditorium (Aud 2) Course website: http://icon This course is designed to introduce students to fundamental principles in the dynamic cell processes, and enhance their understanding of experimental design. Texts and Handouts There are no required textbooks

  8. Radiogenic Strontium-87 as an Index of Geologic Processes.

    PubMed

    Hedge, C E; Walthall, F G

    1963-06-14

    The abundance of radiogenic Sr(87) relative to Sr(86) at the time of crystallization has been determined for 45 rocks. The total range in the ratio Sr(87)/Sr(86) is less than 2 percent. Ratios for recent lavas range from 0.702 to 0.711. Oceanic basalts are closely grouped at 0.703, whereas ratios for continental volcanic rocks spread from 0.702 to 0.711. Among the volcanic rocks, ranging from basalt to rhyolite, no correlation was found between original ratio and rock type. Older mafic and felsic rocks that include both plutonic and extrusive types also cover this same range in original Sr(87)/Sr(86) ratios; however, there is a definite trend with geologic time. Precambrian rocks give values as low as 0.700. The data indicate that Sr(87)/Sr(86) of the weathering crust has changed 1.1 percent in 3000 million years, while the ratio in the mantle has changed no more than 0.5 percent. PMID:17837503

  9. Refining Martian Ages and Understanding Geological Processes From Cratering Statistics

    NASA Technical Reports Server (NTRS)

    Hartmann, William K.

    2005-01-01

    Senior Scientist William K. Hartman presents his final report on Mars Data Analysis Program grant number NAG5-12217: The third year of the three-year program was recently completed in mid-2005. The program has been extremely productive in research and data analysis regarding Mars, especially using Mars Global Surveyor and Mars Odyssey imagery. In the 2005 alone, three papers have already been published, to which this work contributed.1) Hartmann, W. K. 200.5. Martian cratering 8. Isochron refinement and the history of Martian geologic activity Icarus 174, 294-320. This paper is a summary of my entire program of establishing Martian chronology through counts of Martian impact craters. 2) Arfstrom, John, and W. K. Hartmann 2005. Martian flow features, moraine-like rieges, and gullies: Terrestrial analogs and interrelationships. Icarus 174,32 1-335. This paper makes pioneering connections between Martian glacier-like features and terrestrial glacial features. 3) Hartmann, W.K., D. Winterhalter, and J. Geiss. 2005 Chronology and Physical Evolution of Planet Mars. In The Solar System and Beyond: Ten Years of ISSI (Bern: International Space Science Institute). This is a summary of work conducted at the International Space Science Institute with an international team, emphasizing our publication of a conference volume about Mars, edited by Hartmann and published in 2001.

  10. Fundamental spatial array paper performance limitation analysis of multiple machine cross-directional processes

    Microsoft Academic Search

    Junqiang Fan; Gregory E. Stewart

    2005-01-01

    This paper presents a fundamental spatial performance limitation analysis method for multiple array paper machine cross-directional (CD) processes based on a two-dimensional (temporal and spatial) frequency decomposition method. Paper machine CD processes are spatially-distributed dynamical systems. Due to their (almost) spatially invariant characteristic, the models of these systems are considered as transfer matrices with rectangular circulant matrix blocks, whose input

  11. Geological images

    NSDL National Science Digital Library

    Marli Bryant Miller

    This site from Marli Bryant Miller, a professor at the University of Oregon, presents images of geological features from around the world. Photographs of glacial features, igneous and metamorphic rocks and processes, and structural geology are featured.

  12. Processing of Neutron Diffraction Data for Strain Measurement in Geological Materials

    SciTech Connect

    Polsky, Yarom [ORNL] [ORNL; An, Ke [ORNL] [ORNL; Anovitz, Lawrence {Larry} M [ORNL; Bingham, Philip R [ORNL] [ORNL; Carmichael, Justin R [ORNL] [ORNL; Dessieux Jr, Luc Lucius [ORNL] [ORNL

    2014-01-01

    : Conventional rock mechanics testing techniques typically involve the loading of samples and measurement of displacements or strains on the outer boundary of the specimen surface. Neutron diffraction based strain measurement techniques represent a unique and powerful tool for measuring the strain within geological materials under load. The structural variability and non-uniform crystallinity of geological materials, however, create many complexities in the intensity patterns that must be analyzed to quantify strains within the material. The attenuating and scattering properties of the pressure cell housing the sample further add difficulties to the data analysis. This paper describes the methods and processes used to process neutron scattering data for strain measurement in geological materials. It is intended to provide a primer for those in the rock mechanics community that are interested in utilizing this technique along with additional discussion of neutron diffraction experimental factors that may affect data quality.

  13. Fundamental Physical Processes in Coronae: Waves, Turbulence, Reconnection, and Particle Acceleration

    E-print Network

    Aschwanden, Markus J

    2007-01-01

    Our understanding of fundamental processes in the solar corona has been greatly progressed based on the space observations of SMM, Yohkoh, Compton GRO, SOHO, TRACE, RHESSI, and STEREO. We observe now acoustic waves, MHD oscillations, turbulence-related line broadening, magnetic configurations related to reconnection processes, and radiation from high-energy particles on a routine basis. We review a number of key observations in EUV, soft X-rays, and hard X-rays that innovated our physical understanding of the solar corona, in terms of hydrodynamics, MHD, plasma heating, and particle acceleration processes.

  14. ECE 468 Digital Image Processing Catalog Description: Introduction to digital image processing including fundamental concepts

    E-print Network

    ECE 468 ­ Digital Image Processing Catalog Description: Introduction to digital image processing processing. Implementation of algorithms using Matlab Image Processing Toolbox. Credits: 3 Terms Offered Histogram processing Image enhancement, both in the spatial domain and in the frequency domain (through 2D

  15. Processes in karst systems, physics, chemistry, and geology

    SciTech Connect

    Dreybrodt, W.

    1988-01-01

    Dreybrodt deals quantitatively with many of the chemical and hydrological processes involved in the formation of karst systems. The book is divided into 3 major parts. The first part develops the basic chemical and fluid-flow principles needed in modeling karst systems. The second part investigates the experimental kinetics of calcite dissolution and precipitation and applies the resulting kinetic laws to the modeling of these processes in systems both open and closed to carbon dioxide. The last part of the book includes a qualitative examination of karst systems, quantitative modeling of the development of karst features, and an examination and modeling of the growth of spelotherms in caves.

  16. Impacts of Juniper Vegetation and Karst Geology on Subsurface Flow Processes in the Edwards Plateau, Texas

    Microsoft Academic Search

    Surajit Dasgupta; Binayak P. Mohanty; J. Maximilian Köhne

    2006-01-01

    Impacts of Ashe juniper (Juniperus ashei J. Buchholz) and karst geology on the regional water cycle in the Edwards plateau region of Texas are complex and not well understood. The objective of our study was to gain a comprehensive understanding of the subsurface flow processes occurring at a juniper woodland site on the Edwards Plateau near Honey Creek State Natural

  17. Applying Seismic Methods to National Security Problems: Matched Field Processing With Geological Heterogeneity

    Microsoft Academic Search

    S Myers; S Larsen; J Wagoner; B Henderer; D McCallen; J Trebes; P Harben; D Harris

    2003-01-01

    Seismic imaging and tracking methods have intelligence and monitoring applications. Current systems, however, do not adequately calibrate or model the unknown geological heterogeneity. Current systems are also not designed for rapid data acquisition and analysis in the field. This project seeks to build the core technological capabilities coupled with innovative deployment, processing, and analysis methodologies to allow seismic methods to

  18. Lexico-Grammatical Features of Geology Textbooks: Process and Product Revisited.

    ERIC Educational Resources Information Center

    Love, Alison

    1993-01-01

    Examines lexico-grammatical features in an introductory textbook in relation to the thematic organization of the textbook. Comparison is made with a second textbook and the contribution of the lexico-grammatical feature to establish an epistemology of geology. Suggestions are made for supporting English-as-a-Second-Language students in processing

  19. GEOLOGICAL CONTROLS IN THE FORMATIONS AND EXPANSIONS OF GULLIES OVER HILLSLOPE HYDROLOGICAL PROCESSES IN THE

    E-print Network

    Walter, M.Todd

    PROCESSES IN THE HIGHLANDS OF ETHIOPIA, NORTHERN BLUE NILE REGION A Thesis Presented to the Faculty geological material and land use type. #12;Water head upstream of the dyke is near or above surface water pressure development and landslides. Saturated area soils have little strength and result in soil

  20. Use of clay minerals in reconstructing geological processes: recent advances and some perspectives

    Microsoft Academic Search

    J. Srodon

    1999-01-01

    This article reviews that clay literature from the last ten years, which is devoted to the applications of clay minerals in the interpretation of geological processes in sedimentary basins. The results, selected by the author as being of particular interest, are presented, arranged according to the successive phases of the rock cycle. The research field defined in the title has

  1. Impact of food processing industry on geology, soil and ecology: The Nigerian experience

    Microsoft Academic Search

    Ogbonnaya Chukwu

    In developing countries it is common to cite industries without carrying out environmental impact assessment. This is the case of the two industries audited in this study. It becomes necessary therefore to audit food processing industries in Nigeria to determine their impact on geology, soil and ecology. This will enhance a cleaner and healthier environment. In this study the impact

  2. Time-lapse motion picture technique applied to the study of geological processes

    USGS Publications Warehouse

    Miller, R.D.; Crandell, D.R.

    1959-01-01

    Light-weight, battery-operated timers were built and coupled to 16-mm motion-picture cameras having apertures controlled by photoelectric cells. The cameras were placed adjacent to Emmons Glacier on Mount Rainier. The film obtained confirms the view that exterior time-lapse photography can be applied to the study of slow-acting geologic processes.

  3. Feasibility Study for a Plasma Dynamo Facility to Investigate Fundamental Processes in Plasma Astrophysics. Final report

    SciTech Connect

    Forest, Cary B.

    2013-09-19

    The scientific equipment purchased on this grant was used on the Plasma Dynamo Prototype Experiment as part of Professor Forest's feasibility study for determining if it would be worthwhile to propose building a larger plasma physics experiment to investigate various fundamental processes in plasma astrophysics. The initial research on the Plasma Dynamo Prototype Experiment was successful so Professor Forest and Professor Ellen Zweibel at UW-Madison submitted an NSF Major Research Instrumentation proposal titled "ARRA MRI: Development of a Plasma Dynamo Facility for Experimental Investigations of Fundamental Processes in Plasma Astrophysics." They received funding for this project and the Plasma Dynamo Facility also known as the "Madison Plasma Dynamo Experiment" was constructed. This experiment achieved its first plasma in the fall of 2012 and U.S. Dept. of Energy Grant No. DE-SC0008709 "Experimental Studies of Plasma Dynamos," now supports the research.

  4. The large impact process inferred from the geology of lunar multiring basins

    NASA Technical Reports Server (NTRS)

    Spudis, Paul D.

    1992-01-01

    The nature of the impact process has been inferred through the study of the geology of a wide variety of impact crater types and sizes. Some of the largest craters known are the multiring basins found in ancient terrains of the terrestrial planets. Of these features, those found on the Moon possess the most extensive and diverse data coverage, including morphological, geochemical, geophysical, and sample data. The study of the geology of lunar basins over the past 10 years has given us a rudimentary understanding of how these large structures have formed and evolved. The topics covered include basin morphology, basin ejecta, basin excavation, and basin ring formation.

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

    USGS Publications Warehouse

    Lopes, R.M.C.; Stofan, E.R.; Peckyno, R.; Radebaugh, J.; Mitchell, K.L.; Mitri, G.; Wood, C.A.; Kirk, R.L.; Wall, S.D.; Lunine, J.I.; Hayes, A.; Lorenz, R.; Farr, T.; 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/pluvial/lacustrine processes are the most recent, while tectonic processes that led to the formation of mountains and Xanadu are likely the most ancient.

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

    USGS Publications Warehouse

    Lopes, R.M.C.; Stofan, E.R.; Peckyno, R.; Radebaugh, J.; Mitchell, K.L.; Mitri, G.; Wood, C.A.; Kirk, R.L.; Wall, S.D.; Lunine, J.I.; Hayes, A.; Lorenz, R.; Farr, T.; 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 most recent, while tectonic processes that led to the formation of mountains and Xanadu are likely the most ancient. ?? 2009 Elsevier Inc.

  7. Active geologic processes in Barrow Canyon, northeast Chukchi Sea

    USGS Publications Warehouse

    Eittreim, S.; Grantz, A.; Greenberg, J.

    1982-01-01

    Circulation patterns on the shelf and at the shelf break appear to dominate the Barrow Canyon system. The canyon's shelf portion underlies and is maintained by the Alaska Coastal Current (A.C.C.), which flows northeastward along the coast toward the northeast corner of the broad Chukchi Sea. Offshelf and onshelf advective processes are indicated by oceanographic measurements of other workers. These advective processes may play an important role in the production of bedforms that are found near the canyon head as well as in processes of erosion or non-deposition in the deeper canyon itself. Coarse sediments recovered from the canyon axis at 400 to 570 m indicate that there is presently significant flow along the canyon. The canyon hooks left at a point north of Point Barrow where the A.C.C. loses its coastal constriction. The left hook, as well as preferential west-wall erosion, continues down to the abyssal plain of the Canada Basin at 3800 m. A possible explanation for the preferential west-wall erosion along the canyon, at least for the upper few hundred meters, is that the occasional upwelling events, which cause nutrient-rich water to flow along the west wall would in turn cause larger populations of burrowing organisms to live there than on the east wall, and that these organisms cause high rates of bioerosion. This hypothesis assumes that the dominant factor in the canyon's erosion is biological activity, not current velocity. Sedimentary bedforms consisting of waves and furrows are formed in soft mud in a region on the shelf west of the canyon head; their presence there perhaps reflects: (a) the supply of fine suspended sediments delivered by the A.C.C. from sources to the south, probably the Yukon and other rivers draining northwestern Alaska; and (b) the westward transport of these suspended sediments by the prevailing Beaufort Gyre which flows along the outer shelf. ?? 1982.

  8. Rainwater as a chemical agent of geologic processes; a review

    USGS Publications Warehouse

    Carroll, Dorothy

    1962-01-01

    Chemical analyses of the rainwater collected at several localities are given to show the variations of the principal constitutents. In rock weathering and soil-forming processes, the chemical composition of rainwater has an important effect which has been evaluated for only a few arid areas. In humid regions the important amounts of calcium, magnesium, sodium, and potassium added yearly by rain may be expected to influence the composition of the soil water and thereby the cations in the exchange positions of soil clay minerals. The acquisition of cations by clay minerals may slow down chemical weathering. The stability of soil clay minerals is influenced by the constant accession of cations from rainwater. Conversely, the clay minerals modify the amounts and kinds of cations that are leached out by drainage waters. The stability of micaceous minerals in soils may be partly due to accessions of K +1 ions from rainwater. The pH of rainwater in any area varies considerably and seems to form a seasonal and regional pattern. The recorded pH values range from 3.0 to 9.8.

  9. Measuring geologic time on Mars

    Microsoft Academic Search

    Peter T. Doran; Steven L. Forman; Neil C. Sturchio; Stephen M. Clifford; Dimitri A. Papanastassiouje

    2000-01-01

    Recent images from Mars show compelling evidence of near-surface flowing water, aeolian activity, slope processes, and ice cap evolution that underscores the dynamic geologic history of the planet. Establishing an accurate chronology for Martian planetary features is critical for addressing fundamental questions about the evolution of the planet's surface and atmosphere and the differentiation of its interior. For example, how

  10. Analysis of the resin transfer molding (RTM) process for FRP and its process simulation fundamentals

    NASA Astrophysics Data System (ADS)

    Caba, S.; Koch, M.

    2015-05-01

    The industrialization of the resin transfer molding process is a major objective in reducing production cost for FRPs thus making it more competitive for use in large scale applications. Normally, shorter cycle times run into the risk of quality inconsistencies. The creation of voids is influenced by various process parameters, such as mold temperature, resin flow rate and fiber volume content. With knowledge of the effects of these parameters on the process, a specific approach to reducing void content is made while reducing processing time. In order to achieve this objective, in particular, capillary forces and its influence on impregnation of the fiber bundle were examined. A DOE approach was chosen to lead to the determination of interactions. The results target at a pre-determination of required process parameter to obtain consistent part quality with reduced cycle time.

  11. Final report of ''Fundamental Surface Reaction Mechanisms in Fluorocarbon Plasma-Based Processing''

    SciTech Connect

    Gottlieb S. Oehrlein; H. Anderson; J. Cecchi; D. Graves

    2004-09-21

    This report provides a summary of results obtained in research supported by contract ''Fundamental Surface Reaction Mechanisms in Fluorocarbon Plasma-Based Processing'' (Contract No. DE-FG0200ER54608). In this program we advanced significantly the scientific knowledge base on low pressure fluorocarbon plasmas used for patterning of dielectric films and for producing fluorocarbon coatings on substrates. We characterized important neutral and ionic gas phase species that are incident at the substrate, and the processes that occur at relevant surfaces in contact with the plasma. The work was performed through collaboration of research groups at three universities where significantly different, complementary tools for plasma and surface characterization, computer simulation of plasma and surface processes exist. Exchange of diagnostic tools and experimental verification of key results at collaborating institutions, both experimentally and by computer simulations, was an important component of the approach taken in this work.

  12. Fundamental phenomena on fuel decomposition and boundary layer combustion processes with applications to hybrid rocket motors

    NASA Astrophysics Data System (ADS)

    Kuo, Kenneth K.; Lu, Y. C.; Chiaverini, Martin J.; Harting, George C.

    1994-11-01

    An experimental study on the fundamental processes involved in fuel decomposition and boundary layer combustion in hybrid rocket motors is being conducted at the High Pressure Combustion Laboratory of the Pennsylvania State University. This research should provide a useful engineering technology base in the development of hybrid rocket motors as well as a fundamental understanding of the complex processes involved in hybrid propulsion. A high pressure slab motor has been designed and manufactured for conducting experimental investigations. Oxidizer (LOX or GOX) supply and control systems have been designed and partly constructed for the head-end injection into the test chamber. Experiments using HTPB fuel, as well as fuels supplied by NASA designated industrial companies will be conducted. Design and construction of fuel casting molds and sample holders have been completed. The portion of these items for industrial company fuel casting will be sent to the McDonnell Douglas Aerospace Corporation in the near future. The study focuses on the following areas: observation of solid fuel burning processes with LOX or GOX, measurement and correlation of solid fuel regression rate with operating conditions, measurement of flame temperature and radical species concentrations, determination of the solid fuel subsurface temperature profile, and utilization of experimental data for validation of a companion theoretical study (Part 2) also being conducted at PSU.

  13. Fundamental phenomena on fuel decomposition and boundary layer combustion processes with applications to hybrid rocket motors

    NASA Technical Reports Server (NTRS)

    Kuo, Kenneth K.; Lu, Y. C.; Chiaverini, Martin J.; Harting, George C.

    1994-01-01

    An experimental study on the fundamental processes involved in fuel decomposition and boundary layer combustion in hybrid rocket motors is being conducted at the High Pressure Combustion Laboratory of the Pennsylvania State University. This research should provide a useful engineering technology base in the development of hybrid rocket motors as well as a fundamental understanding of the complex processes involved in hybrid propulsion. A high pressure slab motor has been designed and manufactured for conducting experimental investigations. Oxidizer (LOX or GOX) supply and control systems have been designed and partly constructed for the head-end injection into the test chamber. Experiments using HTPB fuel, as well as fuels supplied by NASA designated industrial companies will be conducted. Design and construction of fuel casting molds and sample holders have been completed. The portion of these items for industrial company fuel casting will be sent to the McDonnell Douglas Aerospace Corporation in the near future. The study focuses on the following areas: observation of solid fuel burning processes with LOX or GOX, measurement and correlation of solid fuel regression rate with operating conditions, measurement of flame temperature and radical species concentrations, determination of the solid fuel subsurface temperature profile, and utilization of experimental data for validation of a companion theoretical study (Part 2) also being conducted at PSU.

  14. New technique for the determination of trace noble metal content in geological and process materials

    Microsoft Academic Search

    V. N Mitkin; S. B Zayakina; G. N Anoshin

    2003-01-01

    A new two-step sample preparation technique is proposed for the instrumental determination of trace quantities of noble metals (NM) in refractory geological and process materials. The decomposition procedure is based on the oxidizing fluorination of samples with subsequent sulfatization (OFS) of the sample melt or cake. Fluorination of samples is accomplished using a mixture of KHF2+KBrF4 or KHF2+BrF3 depending on

  15. The fundamental role of fission during r-process nucleosynthesis in neutron star mergers

    NASA Astrophysics Data System (ADS)

    Goriely, S.

    2015-02-01

    The rapid neutron-capture process, or r-process, is known to be of fundamental importance for explaining the origin of approximately half of the A > 60 stable nuclei observed in nature. Despite important efforts, the astrophysical site of the r-process remains unidentified. Here we study r-process nucleosynthesis in a material that is dynamically ejected by tidal and pressure forces during the merging of binary neutron stars. r-process nucleosynthesis during the decompression is known to be largely insensitive to the detailed astrophysical conditions because of efficient fission recycling, producing a composition that closely follows the solar r-abundance distribution for nuclei with mass numbers A > 140. Due to the important role played by fission in such a scenario, the impact of fission is carefully analyzed. We consider different state-of-the-art global models for the determination of the fission paths, nuclear level densities at the fission saddle points and fission fragment distributions. Based on such models, the sensitivity of the calculated r-process abundance distribution is studied. The fission path is found to strongly affect the region of heavy nuclei responsible for the fission recycling, while the fission fragment distribution of nuclei along the A ? 278 isobars defines the abundance pattern of nuclei produced in the 110 ? A ? 170 region. The late capture of prompt fission neutrons is also shown to affect the abundance distribution, and in particular the shape of the third r-process peak around A ? 195.

  16. Applying Seismic Methods to National Security Problems: Matched Field Processing With Geological Heterogeneity

    SciTech Connect

    Myers, S; Larsen, S; Wagoner, J; Henderer, B; McCallen, D; Trebes, J; Harben, P; Harris, D

    2003-10-29

    Seismic imaging and tracking methods have intelligence and monitoring applications. Current systems, however, do not adequately calibrate or model the unknown geological heterogeneity. Current systems are also not designed for rapid data acquisition and analysis in the field. This project seeks to build the core technological capabilities coupled with innovative deployment, processing, and analysis methodologies to allow seismic methods to be effectively utilized in the applications of seismic imaging and vehicle tracking where rapid (minutes to hours) and real-time analysis is required. The goal of this project is to build capabilities in acquisition system design, utilization of full three-dimensional (3D) finite difference modeling, as well as statistical characterization of geological heterogeneity. Such capabilities coupled with a rapid field analysis methodology based on matched field processing are applied to problems associated with surveillance, battlefield management, finding hard and deeply buried targets, and portal monitoring. This project, in support of LLNL's national-security mission, benefits the U.S. military and intelligence community. Fiscal year (FY) 2003 was the final year of this project. In the 2.5 years this project has been active, numerous and varied developments and milestones have been accomplished. A wireless communication module for seismic data was developed to facilitate rapid seismic data acquisition and analysis. The E3D code was enhanced to include topographic effects. Codes were developed to implement the Karhunen-Loeve (K-L) statistical methodology for generating geological heterogeneity that can be utilized in E3D modeling. The matched field processing methodology applied to vehicle tracking and based on a field calibration to characterize geological heterogeneity was tested and successfully demonstrated in a tank tracking experiment at the Nevada Test Site. A three-seismic-array vehicle tracking testbed was installed on site at LLNL for testing real-time seismic tracking methods. A field experiment was conducted over a tunnel at the Nevada Site that quantified the tunnel reflection signal and, coupled with modeling, identified key needs and requirements in experimental layout of sensors. A large field experiment was conducted at the Lake Lynn Laboratory, a mine safety research facility in Pennsylvania, over a tunnel complex in realistic, difficult conditions. This experiment gathered the necessary data for a full 3D attempt to apply the methodology. The experiment also collected data to analyze the capabilities to detect and locate in-tunnel explosions for mine safety and other applications. In FY03 specifically, a large and complex simulation experiment was conducted that tested the full modeling-based approach to geological characterization using E2D, the K-L statistical methodology, and matched field processing applied to tunnel detection with surface seismic sensors. The simulation validated the full methodology and the need for geological heterogeneity to be accounted for in the overall approach. The Lake Lynn site area was geologically modeled using the code Earthvision to produce a 32 million node 3D model grid for E3D. Model linking issues were resolved and a number of full 3D model runs were accomplished using shot locations that matched the data. E3D-generated wavefield movies showed the reflection signal would be too small to be observed in the data due to trapped and attenuated energy in the weathered layer. An analysis of the few sensors coupled to bedrock did not improve the reflection signal strength sufficiently because the shots, though buried, were within the surface layer and hence attenuated. Ability to model a complex 3D geological structure and calculate synthetic seismograms that are in good agreement with actual data (especially for surface waves and below the complex weathered layer) was demonstrated. We conclude that E3D is a powerful tool for assessing the conditions under which a tunnel could be detected in a specific geological setting. Finally, the Lak

  17. A Fundamental Study of Convective Mixing Contributing to Dissolution Trapping of CO2 in Heterogeneous Geologic Media using Surrogate Fluids and Numerical Modeling

    NASA Astrophysics Data System (ADS)

    Illangasekare, Tissa; Agartan, Eliff; Trevisan, Luca; Cihan, Abdullah; Birkholzer, Jens; Zhou, Quanlin

    2013-04-01

    Geologic sequestration of carbon dioxide is considered as an important strategy to slow down global warming and hence climate change. Dissolution trapping is one of the primary mechanisms contributing to long-term storage of supercritical CO2 (scCO2) in deep saline geologic formations. When liquid scCO2 is injected into the formation, its density is less than density of brine. During the movement of injected scCO2 under the effect of buoyancy forces, it is immobilized due to capillary forces. With the progress of time, entrapped scCO2 dissolves in formation brine, and density-driven convective fingers are expected to be generated due to the higher density of the solute compared to brine. These fingers enhance mixing of dissolved CO2 in brine. The development and role of these convective fingers in mixing in homogeneous formations have been studied in past investigations. The goal of this study is to evaluate the contribution of convective mixing to dissolution trapping of scCO2 in naturally heterogeneous geologic formations via laboratory experiments and numerical analyses. To mimic the dissolution of scCO2 in formation brine under ambient laboratory conditions, a group of surrogate fluids were selected according to their density and viscosity ratios, and tested in different fluid/fluid mixtures and variety of porous media test systems. After selection of the appropriate fluid mixture, a set of experiments in a small test tank packed in homogeneous configurations was performed in order to analyze the fingering behavior. A second set of experiments was conducted for layered systems to study the effects of formation heterogeneity on convective mixing. To capture the dominant processes observed in the experiments, a Finite Volume based numerical code was developed. The model was then used to simulate more complex heterogeneous systems that were not represented in the experiments. Results of these analyses suggest that density-driven convective fingers that contributes to mixing in homogeneous formations may not be significantly contributing to mixing and hence dissolution trapping in heterogeneous formations. However, further experimental and modeling investigations are needed to investigate how the geologic architecture that defines the spatial distribution of low permeability zones contributes to overall dissolution trapping.

  18. Fundamental change of granular flows dynamics, deposition and erosion processes at sufficiently high slope angles: insights from laboratory experiments

    NASA Astrophysics Data System (ADS)

    Farin, M.; Mangeney, A.; Roche, O.

    2013-12-01

    Geophysical granular flows commonly interact with their substrate in various ways depending on the mechanical properties of the underlying material. Granular substrates, resulting from deposition of earlier flows or various geological events, are often eroded by avalanches [see Hungr and Evans, 2004 for review]. The entrainment of underlying debris by the flow is suspected to affect flow dynamics because qualitative and quantitative field observations suggest that it can increase the flow velocity and deposit extent, depending on the geological setting and flow type [Sovilla et al., 2006; Iverson et al., 2011]. Direct measurement of material entrainment in nature, however, is very difficult. We conducted laboratory experiments on granular column collapse over an inclined channel with and without an erodible bed of granular material. The controlling parameters were the channel slope angle, the granular column volume and its aspect ratio (i.e. height over length), the inclination of the column with respect to the channel base, the channel width, and the thickness and compaction of the erodible bed. For slope angles below a critical value ?c, between 10° and 16°, the runout distance rf is proportional to the initial column height h0 and is unaffected by the presence of an erodible bed. On slopes greater than ?c, the flow dynamics change fundamentally since a last phase of slow propagation develops at the end of the flow front deceleration, and prolongates significantly the flow duration. This phase has similar characteristics that steady, uniform flows. The slow propagation phase lasts longer for increasing column volume, column inclination with respect to the slope, and channel width, and for decreasing column aspect ratio. It is however independent of the maximum front velocity and, on an erodible bed, of the maximum depth of excavation within the bed. Both on rigid and erodible beds, the increase of the slow propagation phase duration has a crucial effect on the granular flows dynamics and deposition. (i) On a rigid bed, as the slow propagation phase lasts longer, the normalized runout distance rf/h0 is greater for a given slope angle and the front of the flow deposit becomes more round. (ii) On an erodible bed, increasing the duration of the slow phase causes the bed excavation to lasts longer and the increase of the runout distance compared with the case on the rigid bed to be greater; this is even more significant as the bed is less compact. For flows on an erodible bed and if the slope angle is high enough, waves of grains appear in the flow head, at the interface between the flow (white) and the bed (black). These waves are related to the erosion/deposition processes at the base of the flow.

  19. Geological Processes Affecting the Shallow Seafloor Temperature Fields: Results from 2D and 3D Seismic Reflection Data Offshore SW Taiwan

    NASA Astrophysics Data System (ADS)

    Chi, W. C.; Chen, L.; Liu, C. S.; Wang, Y.; Berndt, C.; Han, W. C.; Lin, S.

    2014-12-01

    Seafloor heat flow measurements provide fundamental geophysical information that can be used to better understand tectonic processes. Regional heat flow patterns have been successfully used to study the cooling of the oceanic lithosphere, exhumation of deep crustal materials, strength of the faults, and other geological processes. However, sometimes there are variations of heat flows within a small area, making the interpretation of the heat flows difficult. Here we study the geological processes that can cause such variations. Over the last two decades, we have collected many dense 2D and 3D seismic reflection data offshore SW Taiwan and there is a wide-spread bottom-simulating reflector (BSR) found in the seismic profiles. The BSR is interpreted as associated with the base of the gas hydrate stability zone, and can be used to infer the temperature fields at shallow oceanic crust using a hydrate phase diagram. Such a dense and wide-spread dataset provides an unprecedented opportunity to study processes that can affect temperature fields in scales less than a kilometer. Here we show evidence of bathymetry-induced temperature perturbations at shallow oceanic crust by comparing the BSR-based temperature data with the temperature derived from steady-state 3D finite element modeling. We have also documented focused fluid flow migration along faults and fissures based on elevated temperature fields near those geological features. We also found seismic evidence of abnormal high heat flows caused by rapid erosion. Our results demonstrate that sometimes it is necessary to correct those effects before the heat flow data can be used for regional studies. Our study is among the first to provide observational data to study small-scale geological processes affecting seafloor temperature fields. Such information might also be important for gas and oil reservoir studies.

  20. Canada's Deep Geological Repository For Used Nuclear Fuel -The Geoscientific Site Evaluation Process

    NASA Astrophysics Data System (ADS)

    Hirschorn, S.; Ben Belfadhel, M.; Blyth, A.; DesRoches, A. J.; McKelvie, J. R. M.; Parmenter, A.; Sanchez-Rico Castejon, M.; Urrutia-Bustos, A.; Vorauer, A.

    2014-12-01

    The Nuclear Waste Management Organization (NWMO) is responsible for implementing Adaptive Phased Management, the approach selected by the Government of Canada for long-term management of used nuclear fuel generated by Canadian nuclear reactors. In May 2010, the NWMO published and initiated a nine-step site selection process to find an informed and willing community to host a deep geological repository for Canada's used nuclear fuel. The site selection process is designed to address a broad range of technical and social, economic and cultural factors. The suitability of candidate areas will be assessed in a stepwise manner over a period of many years and include three main steps: Initial Screenings; Preliminary Assessments; and Detailed Site Characterizations. The Preliminary Assessment is conducted in two phases. NWMO has completed Phase 1 preliminary assessments for the first eight communities that entered into this step. While the Phase 1 desktop geoscientific assessments showed that each of the eight communities contains general areas that have the potential to satisfy the geoscientific safety requirements for hosting a deep geological repository, the assessment identified varying degrees of geoscientific complexity and uncertainty between communities, reflecting their different geological settings and structural histories. Phase 2 activities will include a sequence of high-resolution airborne geophysical surveys and focused geological field mapping to ground-truth lithology and structural features, followed by limited deep borehole drilling and testing. These activities will further evaluate the site's ability to meet the safety functions that a site would need to ultimately satisfy in order to be considered suitable. This paper provides an update on the site evaluation process and describes the approach, methods and criteria that are being used to conduct the geoscientific Preliminary Assessments.

  1. Fundamental phenomena on fuel decomposition and boundary layer combustion processes with applications to hybrid rocket motors

    NASA Technical Reports Server (NTRS)

    Kuo, Kenneth K.; Lu, Y. C.; Chiaverini, Martin J.; Harting, George C.

    1994-01-01

    An experimental study on the fundamental processes involved in fuel decomposition and boundary layer combustion in hybrid rocket motors is being conducted at the High Pressure Combustion Laboratory of the Pennsylvania State University. This research should provide an engineering technology base for development of large scale hybrid rocket motors as well as a fundamental understanding of the complex processes involved in hybrid propulsion. A high pressure slab motor has been designed for conducting experimental investigations. Oxidizer (LOX or GOX) is injected through the head-end over a solid fuel (HTPB) surface. Experiments using fuels supplied by NASA designated industrial companies will also be conducted. The study focuses on the following areas: measurement and observation of solid fuel burning with LOX or GOX, correlation of solid fuel regression rate with operating conditions, measurement of flame temperature and radical species concentrations, determination of the solid fuel subsurface temperature profile, and utilization of experimental data for validation of a companion theoretical study also being conducted at PSU.

  2. Fundamental research on novel process alternatives for coal gasification: Final report

    SciTech Connect

    Hill, A H; Knight, R A; Anderson, G L; Feldkirchner, H L; Babu, S P

    1986-10-01

    The Institute of Gas Technology has conducted a fundamental research program to determine the technical feasibility of and to prepare preliminary process evaluations for two new approaches to coal gasification. These two concepts were assessed under two major project tasks: Task 1. CO/sub 2/-Coal Gasification Process Concept; Task 2. Internal Recirculation Catalysts Coal Gasification Process Concept. The first process concept involves CO/sub 2/-O/sub 2/ gasification of coal followed by CO/sub 2/ removal from the hot product gas by a solid MgO-containing sorbent. The sorbent is regenerated by either a thermal- or a pressure-swing step and the CO/sub 2/ released is recycled back to the gasifier. The product is a medium-Btu gas. The second process concept involves the use of novel ''semivolatile'' materials as internal recirculating catalysts for coal gasification. These materials remain in the gasifier because their vapor pressure-temperature behavior is such that they will be in the vapor state at the hotter, char exit part of the reactor and will condense in the colder, coal-inlet part of the reactor. 21 refs., 43 figs., 43 tabs.

  3. Geodynamics applications of continuum physics to geological problems

    Microsoft Academic Search

    D. L. Turcotte; G. Schubert

    1982-01-01

    This textbook deals with the fundamental physical processes necessary for an understanding of plate tectonics and a variety of geologic phenomena. The first chapter reviews plate tectonics; its main purpose is to provide physics, chemistry, and engineering students with the geologic background necessary to understand the applications throughout the rest of the book. It goes on to discuss in following

  4. Quaternary geology and geomorphology of the Sacramento-San Joaquin Delta, California: evolution and processes

    NASA Astrophysics Data System (ADS)

    Gatti, E.; Maier, K. L.; Holzer, T. L.; Knudsen, K. L.; Olson, H.; Pagenknopp, M.; Ponti, D. J.; Rosa, C.; Tinsley, J. C.; Wan, E.

    2013-12-01

    The Sacramento-San Joaquin Delta (~1,400 km2) is a combination of tidal marsh, islands and agricultural lands at the confluence of the Sacramento and the San Joaquin Rivers, in northern California. Most of the Delta islands are now 3 to 8 m below sea-level and must be protected by levees from inundation. Because of the Delta's crucial role in conveying fresh water to the State, levee failures can cause substantial economic loss by disrupting this supply. Understanding the evolution of the Delta is fundamental to assess the vulnerability of the Delta islands to seismically-induced levee failure. The modern Delta is a young geological feature that began forming during the middle Holocene. Preceding versions of the Delta hosted a variety of depositional environments as sea level fluctuated, responding to climatically-controlled changes. The rising sea reached the Delta about 8,000 years ago, and modern deltaic evolution continued into Holocene time until present. More accurate stratigraphic studies incorporating depositional ages are required to i) better understand the late Quaternary evolution of the Delta, ii) trace the base of Holocene deposits, iii) identify potentially active faults, and iv) evaluate liquefaction hazard for the Delta . This study uses the large amount of data available on the Delta (collected by the California Department of Water Resources and others during the past 30 years) and merges them into a unified dataset. We have produced a database that includes historic and surficial maps, aerial photographs, boreholes, and CPT data, for the purpose of clarifying the nature of the Quaternary deposits and the evolution of the Late Quaternary Delta. Additionally, we have identified recently discovered Pleistocene tephra as the Rockland ash, ~0.575 Ma, and the Loleta ash, ~0.40-0.37 Ma, which have improved stratigraphic correlations and assessment of subsidence rates. Delta sediments include sequences of glacial and interglacial deposits. Borehole logs reveal sequences of incision and backfilling corresponding to major climatic fluctuations: incised channels, sand-filling channels, gravel alluvial fans and eolian dunes during glacial periods, and fine-grained alluvial floodplains, mud flats deposits, marshes and peat during warmer interglacials. The evolution of the Delta is likely the result of three processes: subsidence (based on tephra ages, between ~0.004 cm/yr and 0.007 cm/yr in the Northern Delta, ~0.01 cm/yr in the central Delta, ~0.06 cm/yr in the Eastern Delta), compaction due to organic soil oxidation (3.6-6.1 cm/yr), and tectonic control. The thickness of the organic soils (>20 m) suggests that the Holocene sea-level rise was the major factor controlling the Delta's morphology before agricultural drainage began in the 1850's. Because the patterns suggest that sea-level rise was the major cause of changes in the Delta, it is likely that once the organic soil is all oxidized by anthropogenic processes within a few centuries, the major controlling factor will become anthropogenic sea-level rise.

  5. Quantifying geological processes on Mars-Results of the high resolution stereo camera (HRSC) on Mars express

    NASA Astrophysics Data System (ADS)

    Jaumann, R.; Tirsch, D.; Hauber, E.; Ansan, V.; Di Achille, G.; Erkeling, G.; Fueten, F.; Head, J.; Kleinhans, M. G.; Mangold, N.; Michael, G. G.; Neukum, G.; Pacifici, A.; Platz, T.; Pondrelli, M.; Raack, J.; Reiss, D.; Williams, D. A.; Adeli, S.; Baratoux, D.; de Villiers, G.; Foing, B.; Gupta, S.; Gwinner, K.; Hiesinger, H.; Hoffmann, H.; Deit, L. Le; Marinangeli, L.; Matz, K.-D.; Mertens, V.; Muller, J. P.; Pasckert, J. H.; Roatsch, T.; Rossi, A. P.; Scholten, F.; Sowe, M.; Voigt, J.; Warner, N.

    2015-07-01

    This review summarizes the use of High Resolution Stereo Camera (HRSC) data as an instrumental tool and its application in the analysis of geological processes and landforms on Mars during the last 10 years of operation. High-resolution digital elevations models on a local to regional scale are the unique strength of the HRSC instrument. The analysis of these data products enabled quantifying geological processes such as effusion rates of lava flows, tectonic deformation, discharge of water in channels, formation timescales of deltas, geometry of sedimentary deposits as well as estimating the age of geological units by crater size-frequency distribution measurements. Both the quantification of geological processes and the age determination allow constraining the evolution of Martian geologic activity in space and time. A second major contribution of HRSC is the discovery of episodicity in the intensity of geological processes on Mars. This has been revealed by comparative age dating of volcanic, fluvial, glacial, and lacustrine deposits. Volcanic processes on Mars have been active over more than 4 Gyr, with peak phases in all three geologic epochs, generally ceasing towards the Amazonian. Fluvial and lacustrine activity phases spread a time span from Noachian until Amazonian times, but detailed studies show that they have been interrupted by multiple and long lasting phases of quiescence. Also glacial activity shows discrete phases of enhanced intensity that may correlate with periods of increased spin-axis obliquity. The episodicity of geological processes like volcanism, erosion, and glaciation on Mars reflects close correlation between surface processes and endogenic activity as well as orbit variations and changing climate condition.

  6. Study on fundamental processes of laser welded metals observed with intense x-ray beams

    NASA Astrophysics Data System (ADS)

    Muramatsu, T.; Daido, H.; Shobu, T.; Takase, K.; Tsukimori, K.; Kureta, M.; Segawa, M.; Nishimura, A.; Suzuki, Y.; Kawachi, T.

    With use of photon techniques including visible light, soft and hard x-rays, precise fundamental laser welding processes in the repair and maintenance of nuclear plant engineering were reviewed mechanistically. We make discussions centered on the usefulness of an intense soft x-ray beams for evaluations of spatial residual strain distribution and welded metal convection behavior including the surface morphology. Numerical results obtained with a general purpose three-dimensional code SPLICE for the simulation of the welding and solidifying phenomena. Then it is concluded that the x-ray beam would be useful as one of the powerful tools for understanding the mechanisms of various complex phenomena with higher accuracy and higher resolution.

  7. FUNDAMENTAL STUDIES OF IGNITION PROCESSES IN LARGE NATURAL GAS ENGINES USING LASER SPARK IGNITION

    SciTech Connect

    Azer Yalin; Morgan Defoort; Bryan Willson

    2005-01-01

    The current report details project progress made during the first quarterly reporting period of the DOE sponsored project ''Fundamental studies of ignition processes in large natural gas engines using laser spark ignition''. The goal of the overall research effort is to develop a laser ignition system for natural gas engines, with a particular focus on using fiber optic delivery methods. In this report we present our successful demonstration of spark formation using fiber delivery made possible though the use of novel coated hollow fibers. We present results of (high power) experimental characterizations of light propagation using hollow fibers using both a high power research grade laser as well as a more compact laser. Finally, we present initial designs of the system we are developing for future on-engine testing using the hollow fibers.

  8. Canada's Deep Geological Repository for Used Nuclear Fuel - Geo-scientific Site Evaluation Process - 13117

    SciTech Connect

    Blyth, Alec; Ben Belfadhel, Mahrez; Hirschorn, Sarah; Hamilton, Duncan; McKelvie, Jennifer [Nuclear Waste Management Organization, 22 St. Clair Avenue East, Toronto, Ontario M4T 2S3 (Canada)] [Nuclear Waste Management Organization, 22 St. Clair Avenue East, Toronto, Ontario M4T 2S3 (Canada)

    2013-07-01

    The Nuclear Waste Management Organization (NWMO) is responsible for implementing Adaptive Phased Management (APM), the approach selected by the Government of Canada for long-term management of used nuclear fuel generated by Canadian nuclear reactors. The ultimate objective of APM is the centralized containment and isolation of Canada's used nuclear fuel in a Deep Geological Repository in a suitable rock formation at a depth of approximately 500 meters (m) (1,640 feet [ft]). In May 2010, the NWMO published a nine-step site selection process that serves as the road map to decision-making on the location for the deep geological repository. The safety and appropriateness of any potential site will be assessed against a number of factors, both technical and social in nature. The selected site will be one that can be demonstrated to be able to safely contain and isolate used nuclear fuel, protecting humans and the environment over the very long term. The geo-scientific suitability of potential candidate sites will be assessed in a stepwise manner following a progressive and thorough site evaluation process that addresses a series of geo-scientific factors revolving around five safety functions. The geo-scientific site evaluation process includes: Initial Screenings; Preliminary Assessments; and Detailed Site Evaluations. As of November 2012, 22 communities have entered the site selection process (three in northern Saskatchewan and 18 in northwestern and southwestern Ontario). (authors)

  9. Processes that initiate turbidity currents and their influence on turbidites: A marine geology perspective

    USGS Publications Warehouse

    Piper, David J.W.; Normark, William R.

    2009-01-01

    How the processes that initiate turbidity currents influence turbidite deposition is poorly understood, and many discussions in the literature rely on concepts that are overly simplistic. Marine geological studies provide information on the initiation and flow path of turbidity currents, including their response to gradient. In case studies of late Quaternary turbidites on the eastern Canadian and western U.S. margins, initiation processes are inferred either from real-time data for historical flows or indirectly from the age and contemporary paleogeography, erosional features, and depositional record. Three major types of initiation process are recognized: transformation of failed sediment, hyperpycnal flow from rivers or ice margins, and resuspension of sediment near the shelf edge by oceanographic processes. Many high-concentration flows result from hyperpycnal supply of hyperconcentrated bedload, or liquefaction failure of coarse-grained sediment, and most tend to deposit in slope conduits and on gradients < 0.5?? at the base of slope and on the mid fan. Highly turbulent flows, from transformation of retrogressive failures and from ignitive flows that are triggered by oceanographic processes, tend to cannibalize these more proximal sediments and redeposit them on lower gradients on the basin plain. Such conduit flushing provides most of the sediment in large turbidites. Initiation mechanism exerts a strong control on the duration of turbidity flows. In most basins, there is a complex feedback between different types of turbidity-current initiation, the transformation of the flows, and the associated slope morphology. As a result, there is no simple relationship between initiating process and type of deposit. ?? 2009, SEPM (Society for Sedimentary Geology).

  10. Chemical Sensing for Buried Landmines - Fundamental Processes Influencing Trace Chemical Detection

    SciTech Connect

    PHELAN, JAMES M.

    2002-05-01

    Mine detection dogs have a demonstrated capability to locate hidden objects by trace chemical detection. Because of this capability, demining activities frequently employ mine detection dogs to locate individual buried landmines or for area reduction. The conditions appropriate for use of mine detection dogs are only beginning to emerge through diligent research that combines dog selection/training, the environmental conditions that impact landmine signature chemical vapors, and vapor sensing performance capability and reliability. This report seeks to address the fundamental soil-chemical interactions, driven by local weather history, that influence the availability of chemical for trace chemical detection. The processes evaluated include: landmine chemical emissions to the soil, chemical distribution in soils, chemical degradation in soils, and weather and chemical transport in soils. Simulation modeling is presented as a method to evaluate the complex interdependencies among these various processes and to establish conditions appropriate for trace chemical detection. Results from chemical analyses on soil samples obtained adjacent to landmines are presented and demonstrate the ultra-trace nature of these residues. Lastly, initial measurements of the vapor sensing performance of mine detection dogs demonstrates the extreme sensitivity of dogs in sensing landmine signature chemicals; however, reliability at these ultra-trace vapor concentrations still needs to be determined. Through this compilation, additional work is suggested that will fill in data gaps to improve the utility of trace chemical detection.

  11. Fundamental Study on the Dynamics of Heterogeneity-Enhanced CO2 Gas Evolution in the Shallow Subsurface During Possible Leakage from Deep Geologic Storage Sites

    NASA Astrophysics Data System (ADS)

    Plampin, M. R.; Lassen, R. N.; Sakaki, T.; Pawar, R.; Jensen, K.; Illangasekare, T. H.

    2013-12-01

    A concern for geologic carbon sequestration is the potential for CO2 stored in deep geologic formations to leak upward into shallow freshwater aquifers where it can have potentially detrimental impacts to the environment and human health. Understanding the mechanisms of CO2 exsolution, migration and accumulation (collectively referred to as 'gas evolution') in the shallow subsurface is critical to predict and mitigate the environmental impacts. During leakage, CO2 can move either as free-phase or as a dissolved component of formation brine. CO2 dissolved in brine may travel upward into shallow freshwater systems, and the gas may be released from solution. In the shallow aquifer, the exsolved gas may accumulate near interfaces between soil types, and/or create flow paths that allow the gas to escape through the vadose zone to the atmosphere. The process of gas evolution in the shallow subsurface is controlled by various factors, including temperature, dissolved CO2 concentration, water pressure, background water flow rate, and geologic heterogeneity. However, the conditions under which heterogeneity controls gas phase evolution have not yet been precisely defined and can therefore not yet be incorporated into models used for environmental risk assessment. The primary goal of this study is to conduct controlled laboratory experiments to help fill this knowledge gap. With this as a goal, a series of intermediate-scale laboratory experiments were conducted to observe CO2 gas evolution in porous media at multiple scales. Deionized water was saturated with dissolved CO2 gas under a specified pressure (the saturation pressure) before being injected at a constant volumetric flow rate into the bottom of a 1.7 meter-tall by 5.7 centimeter-diameter column or a 2.4 meter-tall by 40 centimeter-wide column that were both filled with sand in various heterogeneous packing configurations. Both test systems were initially saturated with fresh water and instrumented with soil moisture sensors to monitor the evolution of gas phase through time by measuring the average water content in small sampling volumes of soil. Tensiometers allowed for observation of water pressure through space and time in the test systems, and a computer-interfaced electronic scale continuously monitored the outflow of water from the top of the two test columns. Several packing configurations with five different types of sands were used in order to test the effects of various pore size contrasts and interface shapes on the evolution of the gas phase near soil texture transitions in the heterogeneous packings. Results indicate that: (1) heterogeneity affects gas phase evolution patterns within a predictable range of conditions quantified by the newly introduced term 'oversaturation,' (2) soil transition interfaces where less permeable material overlies more permeable material have a much more pronounced effect on gas evolution than interfaces with opposite orientations, and (3) anticlines (or stratigraphic traps) cause significantly greater gas accumulation than horizontal interfaces. Further work is underway to apply these findings to more realistic, two-dimensional scenarios, and to assess how well existing numerical models can capture these processes.

  12. The Mars Express High Resolution Stereo Camera (HRSC): Mapping Mars and Implications for Geological Processes

    NASA Astrophysics Data System (ADS)

    Jaumann, Ralf; Tirsch, Daniela; Hauber, Ernst; Hoffmann, Harald; Neukum, Gerhard

    2015-04-01

    After 10 years of ESA's Mars Express orbiting the planet its High Resolution Stereo Camera (HRSC) covered about 90 % of the surface in stereo and color with resolutions up to 10 m/pixel. Digital elevation models of up to 50 m grid spacing [1], generated from all suitable datasets of the stereo coverage, currently cover about 40 % of the surface [2]. The geomorphological analysis of surface features, observed by the HRSC indicate major surface modifications by endogenic and exogenic processes on all scales. Endogenic landforms (e.g., tectonic rifts, small basaltic shield volcanoes) were found to be very similar to their equivalents on Earth, suggesting that no unique processes are required to explain their formation. Volcanism may have been active up to the very recent past or even to the present, putting important constraints on thermal evolution models [e.g., 3]. The analysis of diverse landforms produced by aqueous processes revealed that surface water activity was likely episodic, but ranged in age from very ancient to very recent [e.g., 3]. Particularly important is prominent glaciation and periglacial features at several latitudes, including mountain glaciers [e.g., 3]. The identification of aqueous alteration minerals and their geological context has enabled a better understanding of paleoenvironmental conditions and pedogenetic processes [e.g., 4]. Dark dunes contain volcanic material and are evidence for the significantly dynamic surface environment, characterized by widespread erosion, transport, and redeposition [e.g., 3, 5]. Since basically all geologic interpretations of extraterrestrial features require profound knowledge of the Earth as key reference, studies of terrestrial analogues are mandatory in planetary geology. Field work in Antarctica, Svalbard and Iceland [e.g., 6] provided a basis for the analysis of periglacial and volcanic processes, respectively. References: [1] Jaumann et al., 2007, PSS 55, 928-952; [2] Gwinner et al., 2010, EPSL 294, 506-519; [3] Jaumann et al., 2015, PSS, in press, [4] Jaumann et al., 2014, PSS 98, 128-145; [5] Tirsch et al., 2011, JGR 116, doi: 10.1029/2009je003562; [6] Hauber et al., 2011, Geol. Soc. Am. 483, 111-131

  13. Constraining geologic properties and processes through the use of impact craters

    NASA Astrophysics Data System (ADS)

    Barlow, Nadine G.

    2015-07-01

    Impact cratering is the one geologic process which is common to all solar system objects. Impact craters form by the resulting explosion between a solar system body and hypervelocity objects. Comparison with craters formed by chemical and nuclear explosions reveals that crater diameter is related to other morphometric characteristics of the crater, such as depth and rim height. These relationships allow scientists to use impact craters to probe the subsurface structure within the upper few kilometer of a planetary surface and to estimate the amounts and types of degradational processes which have affected the planet since crater formation. Crater size-frequency distribution analysis provides the primary mechanism for determining ages of planetary terrains and constraining the timing of resurfacing episodes. Thus, impact craters provide many important insights into the evolution of planetary surfaces.

  14. US GEOLOGICAL SURVEY'S NATIONAL SYSTEM FOR PROCESSING AND DISTRIBUTION OF NEAR REAL-TIME HYDROLOGICAL DATA.

    USGS Publications Warehouse

    Shope, William G., Jr.

    1987-01-01

    The US Geological Survey is utilizing a national network of more than 1000 satellite data-collection stations, four satellite-relay direct-readout ground stations, and more than 50 computers linked together in a private telecommunications network to acquire, process, and distribute hydrological data in near real-time. The four Survey offices operating a satellite direct-readout ground station provide near real-time hydrological data to computers located in other Survey offices through the Survey's Distributed Information System. The computerized distribution system permits automated data processing and distribution to be carried out in a timely manner under the control and operation of the Survey office responsible for the data-collection stations and for the dissemination of hydrological information to the water-data users.

  15. Geoelectrical signals of geologic and hydrologic processes in a fringing reef lagoon setting

    NASA Astrophysics Data System (ADS)

    Befus, Kevin M.; Cardenas, M. Bayani; Tait, Douglas R.; Erler, Dirk V.

    2014-09-01

    Coastal groundwater may discharge into nearshore and offshore waters forced by terrestrial fluxes, controlled by local geology, and modulated by the hydrodynamics of littoral water. We investigated the electrical signature of these features with a dense, multiscale network of electrical resistivity tomography (ERT) surveys in the Muri Lagoon of Rarotonga, Cook Islands. The ERT surveys spanned from onshore to 400 m into the lagoon and used standard electrodes on land and across the foreshore, submerged electrodes in the shallow subtidal zone, and floating electrodes towed throughout the reef lagoon by a boat. ERT surveys on land mapped a typical freshwater lens underlain by a saltwater wedge, but with possible deviations from the classical model due to an adjacent tidal creek. Further inland, ERT surveys imaged a layer of lava flow deposits that is potentially a confining hydrogeologic unit; this unit was used to constrain the expected electrical resistivity of these deposits below the lagoon. ERT surveys across the intertidal zone and into the lagoon indicated fresh groundwater and porewater salinity patterns consistent with previous small-scale studies including the seaward extension of fresh groundwater pathways to the lagoon. Electrical resistivity (ER) variations in the lagoon subsurface highlighted heterogeneities in the lagoon structure that may focus submarine groundwater discharge (SGD) through previously unknown buried lava flow deposits in the lagoon. A transition to higher ER values near the reef crest is consistent with the ER signature of porosity reduction due to ongoing differential cementation of reef deposits across the lagoon. The imaged coastal hydrostratigraphic heterogeneity may thus control terrestrial and marine porewater mixing, support SGD, and provide the pathways for groundwater and the materials it transports into the lagoon. This hydrogeophysical investigation highlighted the spatial heterogeneity of submarine coastal geology and its hydrogeologic control in a reef lagoon setting, but is likely to occur in many similar coastal settings. Ignoring geologic complexity can result in mischaracterization of SGD and other coastal groundwater processes at many spatial scales.

  16. Fundamental studies of interfacial rheology at multilayered model polymers for coextrusion process

    NASA Astrophysics Data System (ADS)

    Zhang, Huagui; Lamnawar, Khalid; Maazouz, Abderrahim

    2015-05-01

    Fundamental studies have been devoted to the interfacial phenomena at multilayered systems based on two model compatible polymers of PVDF and PMMA with varying molar masses. Linear and nonlinear rheology are demonstrated to be sensitive to the presence of diffuse interphase triggered at polymer/polymer interface. Firstly, the interdiffusion kinetics as well as the interphase development have been investigated using SAOS measurements with results analyzed under Doi-Edwards theory. The PMMA/PVDF mixture, has been examined to own close component monomeric friction coefficients. Based on this physics, a new rheological model was developed to quantify the interdiffusion coefficients. Thereby, rheological and geometrical properties of the interphase have been quantified, as validated by SEM-EDX. Secondly, step strain, shear and uniaxial extension startup were carried out to investigate their sensitivity to the diffuse interphase. An original model was proposed for the stress relaxation of multilayer and that of the interphase. Entanglement lack and weak entanglement intensity at the interface/diffuse interphase make them to be subsequently readily to suffer from interfacial yielding under large deformations. Finally, the interphase development coupled to flow in coextrusion has been considered. Net result between negative effect of chain orientation and favorable effect of flow has been shown to broaden the interphase. Its presence during coextrusion process was demonstrated to significantly weaken the interfacial instabilities.

  17. Pramipexole-induced disruption of behavioral processes fundamental to intertemporal choice.

    PubMed

    Johnson, Patrick S; Stein, Jeffrey S; Smits, Rochelle R; Madden, Gregory J

    2013-05-01

    Evaluating the effects of presession drug administration on intertemporal choice in nonhumans is a useful approach for identifying compounds that promote impulsive behavior in clinical populations, such as those prescribed the dopamine agonist pramipexole (PPX). Based on the results of previous studies, it is unclear whether PPX increases rats' impulsive choice or attenuates aspects of stimulus control. The present study was designed to experimentally isolate behavioral processes fundamental to intertemporal choice and challenge them pharmacologically with PPX administration. In Experiment 1, the hypothesis that PPX increases impulsive choice as a result of enhanced sensitivity to reinforcer delays was tested and disconfirmed. That is, acute PPX diminished delay sensitivity in a manner consistent with disruption of stimulus control whereas repeated PPX had no effect on delay sensitivity. Experiments 2 and 3 elaborated upon this finding by examining the effects of repeated PPX on rats' discrimination of response-reinforcer contingencies and reinforcer amounts, respectively. Accuracy of both discriminations was reduced by PPX. Collectively these results provide no support for past studies that have suggested PPX increases impulsive choice. Instead, PPX impairs stimulus control over choice behavior. The behavioral approach adopted herein could be profitably integrated with genetic and other biobehavioral models to advance our understanding of impulsive behavior associated with drug administration. PMID:23436721

  18. Fundamental process and system design issues in CO2 vapor compression systems

    E-print Network

    Bahrami, Majid

    design issues, including discussions of properties and characteristics of CO2, cycle fundamentals, and discusses important trends and characteristics in the development of CO2 technology in refrigeration, air; Compressor; Heat exchanger Contents 1. Introduction

  19. Application of fundamental kinetic modeling to industrial chlorination and partial oxidation processes

    E-print Network

    Han, Joseph Hsiao-Tien

    2000-01-01

    The Fundamental Kinetic Modeling (FKM) method is able to use a growing amount of elementary kinetic rate constant data to simulate industrial reactions and therefore gain insight and predictive capabilities beyond those of traditional empirical...

  20. Separating macroecological pattern and process: comparing ecological, economic, and geological systems.

    PubMed

    Blonder, Benjamin; Sloat, Lindsey; Enquist, Brian J; McGill, Brian

    2014-01-01

    Theories of biodiversity rest on several macroecological patterns describing the relationship between species abundance and diversity. A central problem is that all theories make similar predictions for these patterns despite disparate assumptions. A troubling implication is that these patterns may not reflect anything unique about organizational principles of biology or the functioning of ecological systems. To test this, we analyze five datasets from ecological, economic, and geological systems that describe the distribution of objects across categories in the United States. At the level of functional form ('first-order effects'), these patterns are not unique to ecological systems, indicating they may reveal little about biological process. However, we show that mechanism can be better revealed in the scale-dependency of first-order patterns ('second-order effects'). These results provide a roadmap for biodiversity theory to move beyond traditional patterns, and also suggest ways in which macroecological theory can constrain the dynamics of economic systems. PMID:25383874

  1. Improved understanding of geologic CO{sub 2} storage processes requires risk-driven field experiments

    SciTech Connect

    Oldenburg, C.M.

    2011-06-01

    The need for risk-driven field experiments for CO{sub 2} geologic storage processes to complement ongoing pilot-scale demonstrations is discussed. These risk-driven field experiments would be aimed at understanding the circumstances under which things can go wrong with a CO{sub 2} capture and storage (CCS) project and cause it to fail, as distinguished from accomplishing this end using demonstration and industrial scale sites. Such risk-driven tests would complement risk-assessment efforts that have already been carried out by providing opportunities to validate risk models. In addition to experimenting with high-risk scenarios, these controlled field experiments could help validate monitoring approaches to improve performance assessment and guide development of mitigation strategies.

  2. Development of a requirements management system for technical decision - making processes in the geological disposal project

    SciTech Connect

    Hiroyoshi Ueda; Katsuhiko Ishiguro; Kazumi Kitayama [Nuclear Waste Management Organization of Japan (NUMO), Mita NN Bldg., 1-23, Shiba 4-Chome, Minato-ku, Tokyo 108-0014 (Japan); Kiyoshi Oyamada [JGC Corporation (Japan); Shoko Sato [Obayashi Corporation (Japan)

    2007-07-01

    NUMO (Nuclear Waste Management Organization of Japan) has a responsibility for implementing geological disposal of vitrified HLW (High-Level radioactive Waste) in the Japanese nuclear waste management programme. Its staged siting procedure was initiated in 2002 by an open call for volunteer sites. Careful management strategy and methodology for the technical decision-making at every milestone are required to prepare for the volunteer site application and the site investigation stages after that. The formal Requirement Management System (RMS) is planned to support the computerized implementation of the specific management methodology, termed the NUMO Structured Approach (NSA). This planned RMS will help for comprehensive management of the decision-making processes in the geological disposal project, change management towards the anticipated project deviations, efficient project driving such as well programmed R and D etc. and structured record-keeping regarding the past decisions, which leads to soundness of the project in terms of the long-term continuity. The system should have handling/management functions for the database including the decisions/requirements in the project in consideration, their associated information and the structures composed of them in every decision-making process. The information relating to the premises, boundary conditions and time plan of the project should also be prepared in the system. Effective user interface and efficient operation on the in-house network are necessary. As a living system for the long-term formal use, flexibility to updating is indispensable. In advance of the formal system development, two-year activity to develop the preliminary RMS was already started. The purpose of this preliminary system is to template the decision/requirement structure, prototype the decision making management and thus show the feasibility of the innovative RMS. The paper describes the current status of the development, focusing on the initial stage including work analysis/modeling and the system conceptualization. (authors)

  3. Fundamental aspects of the heterogeneous flame in the self-propagating high-temperature synthesis (SHS) process

    Microsoft Academic Search

    A. Makino

    2001-01-01

    Recent progress on understanding fundamental mechanisms governing the Self-propagating High-temperature Synthesis (SHS) process, which is characterized by the flame propagation through a matrix of compacted reactive particles and is recognized to hold the practical significance in producing novel solid materials, is reviewed. Here the focus is not only on the theoretical description of the heterogeneous nature in the combustion wave,

  4. Object-aware Business Processes: Fundamental Requirements and their Support in Existing Approaches

    E-print Network

    Ulm, Universität

    maturity of process management technology not all busi- ness processes are adequately supported by it of process management technology. Keywords: Process-aware Information Systems, Object-aware Process Management, Data- driven Process Execution 1. Introduction Business Process Management provides generic

  5. STeP1: A Set of Fundamental Tools for Persian Text Processing

    Microsoft Academic Search

    Mehrnoush Shamsfard; Hoda Sadat Jafari; Mahdi Ilbeygi

    2010-01-01

    Many NLP applications need fundamental tools to convert the input text into appropriate form or format and extract the primary linguistic knowledge of words and sentences. These tools perform segmentation of text into sentences, words and phrases, checking and correcting the spellings, doing lexical and morphological analysis, POS tagging and so on. Persian is among languages with complex preprocessing tasks.

  6. Antarctic Dry Valley analogs for Mars gullies: Geological setting and processes

    NASA Astrophysics Data System (ADS)

    Head, J. W.; Marchant, D. R.; Dickson, J. L.; Levy, J. S.; Morgan, G. A.

    2008-09-01

    Malin and Edgett [1,2] initially described a class of young features on Mars that they termed gullies, consisting of an alcove, a channel and a fan. Restricted to middle and high latitude locations, these features were interpreted to have originated through processes related to the presence of liquid water (through groundwater discharge); the potential presence of liquid water on the surface of Mars currently or in the very recent geological past, when liquid water is metastable [3], generated a host of alternative explanations for the gullies [see summary in 4]. Detailed analysis of the conditions under which H2O could flow as a liquid in the current Mars environment shows a range of conditions under which gully-forming activity is possible [3,5]. Recent observations of changes in gullies, interpreted to mean that a few gullies are currently active [6], have intensified this discussion. Terrestrial analogs to martian environments may provide insight into the processes operating on Mars. For example, the nature of perennial saline springs forming channels on Axel Heiberg Island in the Canadian High Arctic has been used to support the argument that martian gullies formed from subsurface groundwater springs [7]. In this analysis we report on the results of ongoing [8-11] field studies in the Antarctic Dry Valleys (ADV), a hyperarid polar desert analog for Mars [11].

  7. Report of the second meeting of the consultants on coupled processes associated with geological disposal of nuclear waste

    SciTech Connect

    Tsang, Chin-Fu; Mangold, D.C.

    1985-09-01

    The second meeting of the Consultants on Coupled Processes Associated with Geological Disposal of Nuclear Waste occurred on January 15-16, 1985 at Lawrence Berkeley Laboratory (LBL). All the consultants were present except Dr. K. Kovari, who presented comments in writing afterward. This report contains a brief summary of the presentations and discussions from the meeting. The main points of the speakers' topics are briefly summarized in the report. Some points that emerged during the discussions of the presentations are included in the text related to the respective talks. These comments are grouped under the headings: Comments on Coupled Processes in Unsaturated Fractured Porous Media, Comments on Overview of Coupled Processes, Presentations by Consultants on Selected Topics of Current Interest in Coupled Processes, and Recommendations for Underground Field Tests with Applications to Three Geologic Environments.

  8. (Fundamental electron transfer processes at the single crystal semiconductor/liquid interface)

    SciTech Connect

    Lewis, N.S.

    1991-01-01

    The last year's work has focused on several aspects of the fundamental chemistry and physics semiconductor/liquid junction behavior. These projects have been directed primarily towards GaAs/liquid contacts, because GaAs/liquid systems provide high energy conversion efficiencies and offer an opportunity to gain mechanistic understanding of the factors that are important to control in an efficient photoelectrochemical energy conversion system.

  9. [Fundamental electron transfer processes at the single crystal semiconductor/liquid interface]. Progress report

    SciTech Connect

    Lewis, N.S.

    1991-12-31

    The last year`s work has focused on several aspects of the fundamental chemistry and physics semiconductor/liquid junction behavior. These projects have been directed primarily towards GaAs/liquid contacts, because GaAs/liquid systems provide high energy conversion efficiencies and offer an opportunity to gain mechanistic understanding of the factors that are important to control in an efficient photoelectrochemical energy conversion system.

  10. Fluid flow and transport phenomena during geological sequestration of carbon dioxide

    Microsoft Academic Search

    Saikiran Rapaka

    2010-01-01

    Geological sequestration of carbon dioxide (CO2) is one of the key technological options that can play a substantial role in mitigating greenhouse gas emissions in the short term. The long-term fate of CO2 injected into geological formations is dictated by the interplay of many physical phenomenon. Obtaining an understanding of these fundamental processes is crucial to guaranteeing security of the

  11. Taking geoscience to the IMAX: 3D and 4D insight into geological processes using micro-CT

    NASA Astrophysics Data System (ADS)

    Dobson, Katherine; Dingwell, Don; Hess, Kai-Uwe; Withers, Philip; Lee, Peter; Pistone, Mattia; Fife, Julie; Atwood, Robert

    2015-04-01

    Geology is inherently dynamic, and full understanding of any geological system can only be achieved by considering the processes by which change occurs. Analytical limitations mean understanding has largely developed from ex situ analyses of the products of geological change, rather than of the processes themselves. Most methods essentially utilise "snap shot" sampling: and from thin section petrography to high resolution crystal chemical stratigraphy and field volcanology, we capture an incomplete view of a spatially and temporally variable system. Even with detailed experimental work, we can usually only analyse samples before and after we perform an experiment, as routine analysis methods are destructive. Serial sectioning and quenched experiments stopped at different stages can give some insight into the third and fourth dimension, but the true scaling of the processes from the laboratory to the 4D (3D + time) geosphere is still poorly understood. Micro computed tomography (XMT) can visualise the internal structures and spatial associations within geological samples non-destructively. With image resolutions of between 200 microns and 50 nanometres, tomography has the ability to provide a detailed sample assessment in 3D, and quantification of mineral associations, porosity, grain orientations, fracture alignments and many other features. This allows better understanding of the role of the complex geometries and associations within the samples, but the challenge of capturing the processes that generate and modify these structures remains. To capture processes, recent work has focused on developing experimental capability for in situ experiments on geological materials. Data presented will showcase examples from recent experiments where high speed synchrotron x-ray tomography has been used to acquire each 3D image in under 2 seconds. We present a suite of studies that showcase how it is now possible to take quantification of many geological processed into 3D and 4D. This will include tracking the interactions between bubbles and crystals in a deforming magma, the dissolution of individual mineral grains from low grade ores, and quantification of three phase flow in sediments and soils. Our aim is to demonstrate how XMT can provide new insight into dynamic processes in all geoscience disciplines, and give you some insight into where 4D geoscience could take us next.

  12. Geologically Controlled Isotope-Time Patterns Reveal Early Differentiation and Crust Formation Processes

    NASA Astrophysics Data System (ADS)

    Bennett, V. C.; Nutman, A. P.

    2014-12-01

    The mechanisms of continental crust production and evolution in the early Earth remain controversial, as are questions of the relative roles of early differentiation versus subsequent tectonic procssing in creating Earth's chemical signatures. Here we present geologic observations integrated with whole rock major, trace element and Sm-Nd isotopic signatures and combined with U-Pb and Lu-Hf isotopic compositions of zircon populations from the same rocks, from the most extensive early rock record comprising the 3.9 Ga to 3.6 Ga terranes of southwest Greenland. These data reveal repeated patterns of formation of juvenile TTG crust and associated mafic and ultramafic rocks in convergent margin settings followed by formation of more evolved granites [1]. Our new zircon Lu-Hf data from rare 3.6-3.7 Ga tonalites within the Itsaq Gneiss Complex, obtained from single component, non-migmatitic gneisses with simple zircon populations, limited within sample Hf isotopic variability and accurate U-Pb ages, now document extraction of juvenile tonalites from a near chondritic mantle source between 3.9 Ga and 3.6 Ga. The more evolved, granitic rocks in each area show slightly negative initial ?Hf in accord with crustal reworking of the older (3.8-3.9 Ga) gniesses. There is no evidence for Hadean material in the sources of the granitoids. The Hf isotope-time patterns are consistent with juvenile crust production from a mantle source that experienced only modest amounts of prior crustal extraction. They are distinct from those predicted by reprocessing of an enriched Hadean mafic crust, as has been proposed for this region [2] and for the source of the Hadean Jack Hills zircons [3]. The well-documented, time decreasing, positive 142Nd anomalies [e.g., 4] from these rocks are further evidence of crustal derivation from a convecting mantle source, rather than reworking of an enriched mafic lithosphere. The 143Nd isotopic -time patterns are more complex, reflecting the interplay between early Sm/Nd fractionation processes as required by the 142Nd data, juvenile crustal growth and in some cases geologic disturbance of the whole rock Sm-Nd system. [1] Nutman, et al, (2013) Amer. Jour. Sci. 313, 877-911. [2] Naeraa et al.. (2012) Nature 485, 627-631. [3] Kemp et al., (2010) EPSL 296, 45-56. [4] Bennett et al., (20070 Science 318, 1907.

  13. Understanding geological processes: Visualization of rigid and non-rigid transformations

    NASA Astrophysics Data System (ADS)

    Shipley, T. F.; Atit, K.; Manduca, C. A.; Ormand, C. J.; Resnick, I.; Tikoff, B.

    2012-12-01

    Visualizations are used in the geological sciences to support reasoning about structures and events. Research in cognitive sciences offers insights into the range of skills of different users, and ultimately how visualizations might support different users. To understand the range of skills needed to reason about earth processes we have developed a program of research that is grounded in the geosciences' careful description of the spatial and spatiotemporal patterns associated with earth processes. In particular, we are pursuing a research program that identifies specific spatial skills and investigates whether and how they are related to each other. For this study, we focus on a specific question: Is there an important distinction in the geosciences between rigid and non-rigid deformation? To study a general spatial thinking skill we employed displays with non-geological objects that had been altered by rigid change (rotation), and two types of non-rigid change ("brittle" (or discontinuous) and "ductile" (or continuous) deformation). Disciplinary scientists (geosciences and chemistry faculty), and novices (non-science faculty and undergraduate psychology students) answered questions that required them to visualize the appearance of the object before the change. In one study, geologists and chemists were found to be superior to non-science faculty in reasoning about rigid rotations (e.g., what an object would look like from a different perspective). Geologists were superior to chemists in reasoning about brittle deformations (e.g., what an object looked like before it was broken - here the object was a word cut into many fragments displaced in different directions). This finding is consistent with two hypotheses: 1) Experts are good at visualizing the types of changes required for their domain; and 2) Visualization of rigid and non-rigid changes are not the same skill. An additional important finding is that there was a broad range of skill in both rigid and non-rigid reasoning within the panels of science experts. In a second study, individual differences in reasoning about brittle deformations were correlated with reasoning about ductile deformations (e.g., what a bent plastic sheet would look like when unbent). Students who were good at visualizing what something looked like before it was broken were also good at visualizing what something looked like before it was bent, and this skill was not correlated to reasoning about rigid rotations. These findings suggest the cognitive processes that support reasoning about rigid and non-rigid events may differ and thus may require different types of support and training. We do not know if differences between experts and novices result from experience or self-selection, or both. Nevertheless, the range of spatial skill evinced by novices and experts strongly argues for designing visualizations to support a variety of users.

  14. Interface Induced Carbonate Mineralization: A Fundamental Geochemical Process Relevant to Carbon Sequestration

    SciTech Connect

    Teng, H. Henry [PI, The George Washington University] [PI, The George Washington University; Xu, Huifang [Co-PI, University of Wisconsin-Madison] [Co-PI, University of Wisconsin-Madison

    2013-07-17

    We have approached the long-standing geochemical question why anhydrous high-Mg carbonate minerals (i.e., magnesite and dolomite) cannot be formed at ambient conditions from a new perspective by exploring the formation of MgCO{sub 3} and Mg{sub x}Ca{sub (1-x)}CO{sub 3} in non-aqueous solutions. Data collected from our experiments in this funding period suggest that a fundamental barrier, other than cation hydration, exists that prevents Mg{sup 2+} and CO{sub 3}{sup 2-} ions from forming long-range ordered structures. We propose that this barrier mainly stems from the lattice limitation on the spatial configuration of CO{sub 3} groups in magnesite crystals. On the other hand, the measured higher distribution coefficients of Mg between magnesian calcites formed in the absence and presence of water give us a first direct proof to support and quantify the cation hydration effect.

  15. Processing and geologic analysis of conventional cores from well ER-20-6 No. 1, Nevada Test Site

    SciTech Connect

    Prothro, L.B., Townsend, M.J.; Drellack, S.L. Jr. [and others

    1997-09-01

    In 1996, Well Cluster ER-20-6 was drilled on Pahute Mesa in Area 20, in the northwestern corner of the Nevada Test Site (NTS). The three wells of the cluster are located from 166 to 296 meters (m) (544 to 971 feet [ft]) southwest of the site of the underground nuclear test code-named BULLION, conducted in 1990 in Emplacement Hole U-20bd. The well cluster was planned to be the site of a forced-gradient experiment designed to investigate radionuclide transport in groundwater. To obtain additional information on the occurrence of radionuclides, nature of fractures, and lithology, a portion of Well ER-20-6 No. 1, the hole closest to the explosion cavity, was cored for later analysis. Bechtel Nevada (BN) geologists originally prepared the geologic interpretation of the Well Cluster ER-20-6 site and documented the geology of each well in the cluster. However, the cores from Well ER-20-6 No. 1 were not accessible at the time of that work. As the forced-gradient experiment and other radio nuclide migration studies associated with the well cluster progressed, it was deemed appropriate to open the cores, describe the geology, and re-package the core for long-term air-tight storage. This report documents and describes the processing, geologic analysis, and preservation of the conventional cores from Well ER20-6 No. 1.

  16. New technique for the determination of trace noble metal content in geological and process materials

    NASA Astrophysics Data System (ADS)

    Mitkin, V. N.; Zayakina, S. B.; Anoshin, G. N.

    2003-02-01

    A new two-step sample preparation technique is proposed for the instrumental determination of trace quantities of noble metals (NM) in refractory geological and process materials. The decomposition procedure is based on the oxidizing fluorination of samples with subsequent sulfatization (OFS) of the sample melt or cake. Fluorination of samples is accomplished using a mixture of KHF 2+KBrF 4 or KHF 2+BrF 3 depending on the ratio of sample mass to oxidizing mixture. Both cakes and melts can result using this procedure. Sulfatization of resulting fluorides is completed using concentrated sulfuric acid heated to 550 °C. Validation studies using certified geostandard reference materials (GSO VP-2, ZH-3, Matte RTP, HO-1, SARM-7) have shown that the proposed method is fast, convenient and most often produces non-hygroscopic homogeneous residues suitable for analysis by atomic absorption spectrometry (AAS) and atomic emission spectrometry (AES). Results obtained for NM concentrations in reference materials agreed with certified concentration ranges and results obtained using other methods of analysis. The OFS procedure combined with direct current plasma d.c. plasma AES achieved the following limits of detection (LOD) for the noble metals: Ag, Au, Pd, 1-2×10 -6; Pt, 5×10 -6; and Ru, Rh, Ir, Os, 1-3×10 -7 wt.%. Using graphite furnace AAS (GFAAS) combined extraction pre-concentration the following LODs for NMs were achieved: Pt, Ru, 1×10 -6; Pd, Rh, 1×10 -7; and Au, Ag, 1-2×10 -8 wt.%. The relative standard deviation for NM determinations ( Sr) was dependent on NM concentration and sample type, but commonly was in the range of 3-15% for d.c. plasma AES and 5-30% for GFAAS.

  17. Fundamental changes of granular flows dynamics, deposition and erosion processes at high slope angles: insights from laboratory experiments.

    NASA Astrophysics Data System (ADS)

    Farin, Maxime; Mangeney, Anne; Roche, Olivier

    2014-05-01

    Geophysical granular flows commonly interact with their substrate in various ways depending on the mechanical properties of the underlying material. Granular substrates, resulting from deposition of earlier flows or various geological events, are often eroded by avalanches [see Hungr and Evans, 2004 for review]. The entrainment of underlying debris by the flow is suspected to affect flow dynamics because qualitative and quantitative field observations suggest that it can increase the flow velocity and deposit extent, depending on the geological setting and flow type [Sovilla et al., 2006; Iverson et al., 2011]. Direct measurement of material entrainment in nature, however, is very difficult. We conducted laboratory experiments on granular column collapse over an inclined channel with and without an erodible bed of granular material. The controlling parameters were the channel slope angle, the granular column volume and its aspect ratio (i.e. height over length), the inclination of the column with respect to the channel base, the channel width, and the thickness and compaction of the erodible bed. For slope angles below a critical value ?c, between 10° and 16°, the runout distance rf is proportional to the initial column height h0 and is unaffected by the presence of an erodible bed. On steeper slopes, the flow dynamics change fundamentally since a last phase of slow propagation develops at the end of the flow front deceleration, and prolongates significantly the flow duration. This phase has similar characteristics that steady, uniform flows. The slow propagation phase lasts longer for increasing slope angle, column volume, column inclination with respect to the slope, and channel width, and for decreasing column aspect ratio. It is however independent of the maximum front velocity and, on an erodible bed, of the maximum depth of excavation within the bed. Both on rigid and erodible beds, the increase of the slow propagation phase duration has a crucial effect on the granular flows dynamics and deposition. (i) Over a rigid bed, as the slow propagation phase lasts longer, the normalized runout distance rf/h0 is greater for a given slope angle and the front of the flow deposit becomes steeper. (ii) Over an erodible bed, increasing the duration of the slow phase causes the bed excavation to lasts longer and leads to the increase of the runout distance compared with the case on the rigid bed being greater; this is even more significant as the bed is less compact.

  18. Role of geology in diamond project development

    NASA Astrophysics Data System (ADS)

    Jakubec, Jaroslav

    2004-09-01

    For a mining operation to be successful, it is important to bring fundamental and applied science together. The mining engineer needs to understand the importance of geology, mineralogy and petrography, and how projects can benefit from the data collected during the exploration and pre-exploration stage. Geological scientists also need to understand the process of project development from the exploration stage through mine design and operation to mine closure. Kimberlite pipe or dyke emplacement, geology and petrology/mineralogy are three areas that illustrate how information obtained from the geological studies could directly influence the mining method selection and the project strategy and design. Kimberlite emplacement is one of the fundamental processes that rely on knowledge of the kimberlite body geology. Although the importance of the emplacement model is commonly recognized in the resource geology, mining engineers do not always appreciate its importance to the mine design. The knowledge of the orebody geometry, character of the contact zones, internal structures and distribution of inclusions could directly influence pit wall stability (thus strip ratio), underground mining method selection, dilution, treatability, and the dewatering strategy. Understanding the internal kimberlite geology mainly includes the geometry and character of individual phases, and the orientation and character of internal structures that transect the rock mass. For any mining method it is important to know "where the less and where the more competent rocks are located" to achieve stability. On the other hand, the detailed facies studies may not be important for the resource and mine design if the rock types have similar physical properties and diamond content. A good understanding of the kimberlite petrology and mineralogy could be crucial not only to the treatability (namely diamond damage and liberation), but also to the pit wall and underground excavation stability, support design, mine safety (mudrush risk assessment) and mine dewatering. There is no doubt that a better understanding of the kimberlite and country rock geology has a direct impact on the safety and economics of the mining operations. The process of mine design can start at the beginning of kimberlite discovery by incorporating the critical geological information without necessarily increasing the exploration budget. It is important to appreciate the usefulness of fundamental geological research and its impact on increased confidence in the mine design. Such studies should be viewed as worthwhile investments, not as cost items.

  19. Discussion of fundamental processes in dielectric barrier discharges used for soft ionization

    NASA Astrophysics Data System (ADS)

    Horvatic, Vlasta; Vadla, Cedomil; Franzke, Joachim

    2014-10-01

    Permanent need for simple to apply and efficient methods for molecular mass spectrometry resulted in the development of a variety of methods now commonly termed ambient desorption/ionization mass spectrometry (ADI-MS), which experienced a very rapid development during the last 10 years. The most widely used techniques are direct analysis in real time (DART), plasma assisted desorption/ionization (PADI), flowing afterglow-atmospheric pressure glow discharge ionization (FA-APGDI), low-temperature plasma probe (LTP) and dielectric barrier discharge ionization (DBDI). They all share the advantage of direct, ambient analysis of samples with little or no pretreatment, and employ some kind of electrical discharge to desorb and ionize the analyte species. However, the investigations focused on the characterization, examination and understanding of underlying ionization mechanisms of these discharges are relatively small in number. More efforts are clearly needed in this segment, since the understanding of the fundamentals of these discharges is a prerequisite for optimization of working parameters of ADI-MS sources with the aim of increasing ionization efficiency. Here, ADI-MS techniques will be overviewed, with the emphasis put on the review and the analysis of the recent progress in dielectric barrier discharges utilized for soft ionization.

  20. Fundamental processes in pair plasmas. [electron-positron relativistic plasmas in quasars and active galaxies

    NASA Technical Reports Server (NTRS)

    Lightman, A. P.

    1983-01-01

    The various processes that produce and destroy electron-positron pairs are reviewed, and the timescales of these processes are compared to thermalization, accretion, and cooling timescales. The various radiation spectra produced by relativistic, thermal plasmas are considered. Recent results for the equilibria available to finite, thermal relativistic plasmas with and without embedded magnetic fields are reviewed. Such plasmas, in steady state, have maximum temperatures, luminosities, and field strengths, useful diagnostics for interpreting quasars and active galaxies.

  1. IGIS (Interactive Geologic Interpretation System) computer-aided photogeologic mapping with image processing, graphics and CAD/CAM capabilities

    SciTech Connect

    McGuffie, B.A.; Johnson, L.F.; Alley, R.E.; Lang, H.R. (California Institute of Technology, Pasadena (USA))

    1989-10-01

    Advances in computer technology are changing the way geologists integrate and use data. Although many geoscience disciplines are absolutely dependent upon computer processing, photogeological and map interpretation computer procedures are just now being developed. Historically, geologists collected data in the field and mapped manually on a topographic map or aerial photographic base. New software called the interactive Geologic Interpretation System (IGIS) is being developed at the Jet Propulsion Laboratory (JPL) within the National Aeronautics and Space Administration (NASA)-funded Multispectral Analysis of Sedimentary Basins Project. To complement conventional geological mapping techniques, Landsat Thematic Mapper (TM) or other digital remote sensing image data and co-registered digital elevation data are combined using computer imaging, graphics, and CAD/CAM techniques to provide tools for photogeologic interpretation, strike/dip determination, cross section construction, stratigraphic section measurement, topographic slope measurement, terrain profile generation, rotatable 3-D block diagram generation, and seismic analysis.

  2. Some fundamental questions concerning healthcare from a process-based systems perspective

    Microsoft Academic Search

    Elisabeth Dostal; György G. Jįros; Barry Baker

    1998-01-01

    In this article various aspects of healthcare are discussed in terms of teleonics, which is a process-based systems framework developed by Jaros and Cloete (1987, 1991 and 1994). Various theoretical concepts of teleonics are introduced and discussed in relation to the nature of health and disease. Based on this discussion, some questions are raised that need to be answered in

  3. Role of fundamental defect processes in irradiation correlation in structural materials for nuclear energy systems

    NASA Astrophysics Data System (ADS)

    Ishino, Shiori

    A number of recent problems in structural materials for nuclear energy systems require quantitative and reliable predictions of materials behaviour in as yet unrealized operating conditions. An example is found in pressure vessel steels of a light water reactor, where prediction of embrittlement of the steel for extended period of service must be done with confidence, because the integrity of the pressure vessel is of vital importance for the safety of the light water reactor. Light water reactor fuel, cladding and wrapper of a fast breeder reactor and first wall and blanket structural materials of a fusion reactor are such examples that are briefly discussed. In such problems, we have either scarce data or limited and rather irrelevant data of the materials performance for the service conditions of the materials in question. The method used to predict the irradiation behaviour of materials from incomplete existing data is called irradiation correlation. The correlation methodology is discussed. To describe the materials behaviour, the component processes should be modelled in terms of elemental defect processes. These models are then integrated to describe the materials behaviour. Charged particle irradiations have been most successfully applied for the study of the component processes because the associated defect processes are studied with less ambiguity largely due to the controllability of experimental conditions. Systematically changing the single experimental parameter among various influencing parameters is vitally important. A successful example of the irradiation correlation is discussed.

  4. A COMPLETE FERREDOXIN/THIOREDOXIN SYSTEM REGULATES FUNDAMENTAL PROCESSES IN AMYLOPLASTS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A growing number of processes throughout biology are regulated by redox via thiol-disulfide exchange. This mechanism is particularly widespread in plants where almost 200 proteins have been linked to thioredoxin (Trx), a widely distributed small regulatory disulfide protein. The current study extend...

  5. Influence in the Policy Making Process: the Rise of Economics at the Expense of Geology

    NASA Astrophysics Data System (ADS)

    McCurdy, K. M.

    2007-12-01

    Scientific influence in resource policy making reached a zenith in the early 1970s during the legislative monopoly in the United States Congress that produced command and control regulatory protection policies. This congressional consensus began in 1879 with legislation producing the U.S. Geological Survey. Other scientific agencies followed. The Congresses of the first half of the 20th century merely strengthened the influence of science in policy outcomes that was present in the earliest congressional debates. What then happened at the turn of the 21st century when representatives in the administration frequently dismissed sound science in their policy deliberations? Policy monopolies arise from agreement in principle, and alternately decline as rival ideas gain hold in policy space. The science policy monopoly began to face competition from economics when cost benefit analysis was introduced into political parlance in 1936, again in the 1950s as a successful blocking tactic by the minority in opposition to western dams, and in 1961 when systems analysis was introduced to the Department of Defense under Robert McNamara. As businessmen replaced farmers as the modal profession of legislators, the language of politics increasingly contained economic terms and concepts. A ternary diagram and a budget simplex have the same shape, but have different theoretical meanings and imply different processes. Policy consensus is not dissimilar to a mineral phase diagram, with boundary conditions marked by election magnitudes and majority parties. The 1980 elections brought economic principles into all aspects of government decision-making, with a particular long-term interest in reducing the size and scope of government. Since then the shift in policy jargon from science to economics has been incremental. With the 1994 Republican legislative majority, scientists, their programs, and the funds required to maintain data collection projects became targets. The Conservative Consensus resulting from the 2000 elections has disregarded and even ridiculed scientific experts, their analyses, and their data. The first step in rebuilding an effective policy consensus based on sound science is recognizing the phase transition that privileges conservative policy solutions which minimize science and elevate economic principles.

  6. Lubrication-related residue as a fundamental process scaling limit to gravure printed electronics.

    PubMed

    Kitsomboonloha, Rungrot; Subramanian, Vivek

    2014-04-01

    In gravure printing, excess ink is removed from a patterned plate or roll by wiping with a doctor blade, leaving a thin lubrication film in the nonpatterned area. Reduction of this lubrication film is critical for gravure printing of electronics, since the resulting residue can lower device performance or even catastrophically impact circuit yield. We report on experiments and quantitative analysis of lubrication films in a highly scaled gravure printing process. We investigate the effects of ink viscosity, wiping speed, loading force, blade stiffness and blade angle on the lubrication film, and further, use the resulting data to investigate the relevant lubrication regimes associated with wiping during gravure printing. Based on this analysis, we are able to posit the lubrication regime associated with wiping during gravure printing, provide insight into the ultimate limits of residue reduction, and, furthermore, are able to provide process guidelines and design rules to achieve these limits. PMID:24625096

  7. LMIs - a fundamental tool in analysis and controller design for discrete linear repetitive processes

    Microsoft Academic Search

    K. Galkowski; Eric Rogers; S. Xu; J. Lam; D. H. Owens

    2002-01-01

    Discrete linear repetitive processes are a distinct class of two-dimensional (2-D) linear systems with applications in areas ranging from long-wall coal cutting through to iterative learning control schemes. The feature which makes them distinct from other classes of 2-D linear systems is that information propagation in one of the two distinct directions only occurs over a finite duration. This, in

  8. Signal-to-noise ratio: a fundamental and broad process performance measure

    Microsoft Academic Search

    Pathik Mandal

    2012-01-01

    The signal-to-noise (S\\/N) ratios proposed by Taguchi have attracted severe criticism from a large number of researchers. However, this article takes a different view. It is shown that these S\\/N ratios, when evaluated judiciously, can act as very useful process performance measures. The famous Wheatstone bridge example is reanalysed in detail and various thermodynamic models are constructed to establish the

  9. Geologic Maps

    NSDL National Science Digital Library

    Russell Graymer

    This web site provides an introduction to geologic maps. Topics covered include what is a geologic map, unique features of geologic maps, letter symbols, faults, and strike and dip. Users may click to view colored geologic maps, the geologic map of the United States and the geologic relief map of the United States.

  10. Fundamental Limits of Electronic Signal Processing in Direct-Detection Optical Communications

    NASA Astrophysics Data System (ADS)

    Franceschini, Michele; Bongiorni, Giorgio; Ferrari, Gianluigi; Raheli, Riccardo; Meli, Fausto; Castoldi, Andrea

    2007-07-01

    Electronic signal processing is becoming very attractive to overcome various impairments that affect optical communications, and electronic dispersion compensation (EDC) represents a typical application in the currently designed systems. However, the inherent limits in performance achievable by electronically processing the signal at the output of a nonlinear photodetector have not received the attention they deserve. In this paper, we investigate the information-theoretic limits of electronic signal processing in transmission systems employing direct photodetection and two possible modulation formats: 1) on off keying (OOK) with nonreturn-to-zero pulses; and 2) optical duobinary modulation (ODBM). The analysis is based on the computation of the information rate, i.e., the maximum achievable data transfer rate, and accounts for the modulation format as well as relevant parameters of the transmission scheme. In particular, we investigate the impact of sampling rate, uncompensated chromatic dispersion (CD), and quantization resolution of the electrical signal at the output of a direct photodetector. For OOK systems, the obtained results show that the optical signal-to-noise ratio penalty entailed by EDC can be limited to about 2 dB at most values of CD of interest in current applications. Moreover, ODBM systems at high values of CD can almost perform as OOK systems at zero CD. For all the considered modulation formats, the obtained results show that the received electrical signal can be sampled at a rate of two samples per bit interval and quantized with a precision of 3 bits per sample to practically achieve the ultimate performance limits.

  11. Combustion Fundamentals Research

    NASA Technical Reports Server (NTRS)

    1983-01-01

    Increased emphasis is placed on fundamental and generic research at Lewis Research Center with less systems development efforts. This is especially true in combustion research, where the study of combustion fundamentals has grown significantly in order to better address the perceived long term technical needs of the aerospace industry. The main thrusts for this combustion fundamentals program area are as follows: analytical models of combustion processes, model verification experiments, fundamental combustion experiments, and advanced numeric techniques.

  12. Thioredoxin targets fundamental processes in a methane-producing archaeon, Methanocaldococcus jannaschii

    PubMed Central

    Susanti, Dwi; Wong, Joshua H.; Vensel, William H.; Loganathan, Usha; DeSantis, Rebecca; Schmitz, Ruth A.; Balsera, Monica; Buchanan, Bob B.; Mukhopadhyay, Biswarup

    2014-01-01

    Thioredoxin (Trx), a small redox protein, controls multiple processes in eukaryotes and bacteria by changing the thiol redox status of selected proteins. The function of Trx in archaea is, however, unexplored. To help fill this gap, we have investigated this aspect in methanarchaea—strict anaerobes that produce methane, a fuel and greenhouse gas. Bioinformatic analyses suggested that Trx is nearly universal in methanogens. Ancient methanogens that produce methane almost exclusively from H2 plus CO2 carried approximately two Trx homologs, whereas nutritionally versatile members possessed four to eight. Due to its simplicity, we studied the Trx system of Methanocaldococcus jannaschii—a deeply rooted hyperthermophilic methanogen growing only on H2 plus CO2. The organism carried two Trx homologs, canonical Trx1 that reduced insulin and accepted electrons from Escherichia coli thioredoxin reductase and atypical Trx2. Proteomic analyses with air-oxidized extracts treated with reduced Trx1 revealed 152 potential targets representing a range of processes—including methanogenesis, biosynthesis, transcription, translation, and oxidative response. In enzyme assays, Trx1 activated two selected targets following partial deactivation by O2, validating proteomics observations: methylenetetrahydromethanopterin dehydrogenase, a methanogenesis enzyme, and sulfite reductase, a detoxification enzyme. The results suggest that Trx assists methanogens in combating oxidative stress and synchronizing metabolic activities with availability of reductant, making it a critical factor in the global carbon cycle and methane emission. Because methanogenesis developed before the oxygenation of Earth, it seems possible that Trx functioned originally in metabolic regulation independently of O2, thus raising the question whether a complex biological system of this type evolved at least 2.5 billion years ago. PMID:24505058

  13. Thioredoxin targets fundamental processes in a methane-producing archaeon, Methanocaldococcus jannaschii.

    PubMed

    Susanti, Dwi; Wong, Joshua H; Vensel, William H; Loganathan, Usha; DeSantis, Rebecca; Schmitz, Ruth A; Balsera, Monica; Buchanan, Bob B; Mukhopadhyay, Biswarup

    2014-02-18

    Thioredoxin (Trx), a small redox protein, controls multiple processes in eukaryotes and bacteria by changing the thiol redox status of selected proteins. The function of Trx in archaea is, however, unexplored. To help fill this gap, we have investigated this aspect in methanarchaea--strict anaerobes that produce methane, a fuel and greenhouse gas. Bioinformatic analyses suggested that Trx is nearly universal in methanogens. Ancient methanogens that produce methane almost exclusively from H2 plus CO2 carried approximately two Trx homologs, whereas nutritionally versatile members possessed four to eight. Due to its simplicity, we studied the Trx system of Methanocaldococcus jannaschii--a deeply rooted hyperthermophilic methanogen growing only on H2 plus CO2. The organism carried two Trx homologs, canonical Trx1 that reduced insulin and accepted electrons from Escherichia coli thioredoxin reductase and atypical Trx2. Proteomic analyses with air-oxidized extracts treated with reduced Trx1 revealed 152 potential targets representing a range of processes--including methanogenesis, biosynthesis, transcription, translation, and oxidative response. In enzyme assays, Trx1 activated two selected targets following partial deactivation by O2, validating proteomics observations: methylenetetrahydromethanopterin dehydrogenase, a methanogenesis enzyme, and sulfite reductase, a detoxification enzyme. The results suggest that Trx assists methanogens in combating oxidative stress and synchronizing metabolic activities with availability of reductant, making it a critical factor in the global carbon cycle and methane emission. Because methanogenesis developed before the oxygenation of Earth, it seems possible that Trx functioned originally in metabolic regulation independently of O2, thus raising the question whether a complex biological system of this type evolved at least 2.5 billion years ago. PMID:24505058

  14. Exploratory cell research and fundamental processes study in solid state electrochemical cells

    SciTech Connect

    Smyrl, W.H.; Owens, B.B.; White, H.S. (Minnesota Univ., Minneapolis, MN (USA). Dept. of Chemical Engineering and Materials Science)

    1990-06-01

    Last year this program demonstrated that alternative to lithium had some merit on which to base new polymer electrolyte batteries and other electrochemical devices. We reported that Na, Zn, and Cu electrolytes have modest conductivities at 100{degree}C. Some preliminary cell cycling data were reported with V{sub 6}O{sub 13} insertion cathodes, and the successful cell cycling suggested that N{sup +}, Zn{sup +2} could be inserted and removed reversibly in the cathode material. Also, thin-film polymer cathodes were shown by impedance measurements to have three characteristic regions of behavior. Each region had different controlling processes with relaxation time constants that could be separated with careful manipulation of film thickness, morphology, and charging level. The present report gives results of the continuation of these studies. In particular, the sodium system was studied more intensively with conductivity measurements on sodium triflate in poly(ethyleneoxide)(PEO), and cell studies with V{sub 6}O{sub 13} and poly(pyrrole)(PPY) cathodes. The impedance work was concluded and several directions of new work in that area were identified. The insertion studies with single crystal V{sub 6}O{sub 13} were concluded on this program and transferred to NSF funding. 29 refs., 6 figs., 6 tabs.

  15. Exploratory cell research and fundamental processes study in solid state electrochemical cells

    NASA Astrophysics Data System (ADS)

    Smyrl, William H.; Owens, Boone B.; White, Henry S.

    1990-06-01

    Last year this program demonstrated that some alternatives to lithium had some merit on which to base new polymer electrolyte batteries and other electrochemical devices. We reported that Na, Zn, and Cu electrolytes have modest conductivities at 100 C. Some preliminary cell cycling data were reported with V6 O13 insertion cathodes, and the successful cell cycling suggested that N(sup +), Zn(sup +2) could be inserted and removed reversibly in the cathode material. Also, thin-film polymer cathodes were shown by impedance measurements to have three characteristic regions of behavior. Each region had different controlling processes with relaxation time constants that could be separated with careful manipulation of film thickness, morphology, and charging level. The present report gives results of the continuation of these studies. In particular, the sodium system was studied more intensively with conductivity measurements on sodium triflate in poly(ethyleneoxide)(PEO), and cell studies with V6 O13 and poly(pyrrole)(PPY) cathodes. The impedance work was concluded and several directions of new work in that area were identified. The insertion studies with single crystal V6 O13 were concluded on this program.

  16. Hydrogel microparticles from lithographic processes: novel materials for fundamental and applied colloid science

    PubMed Central

    Helgeson, Matthew E.; Chapin, Stephen C.; Doyle, Patrick S.

    2011-01-01

    In recent years there has been a surge in methods to synthesize geometrically and chemically complex microparticles. Analogous to atoms, the concept of a “periodic table” of particles has emerged and continues to be expanded upon. Complementing the natural intellectual curiosity that drives the creation of increasingly intricate particles is the pull from applications that take advantage of such high-value materials. Complex particles are now being used in fields ranging from diagnostics and catalysis to self-assembly and rheology, where material composition and microstructure are closely linked with particle function. This is especially true of polymer hydrogels, which offer an attractive and broad class of base materials for synthesis. Lithography affords the ability to engineer particle properties a priori and leads to the production of homogenous ensembles of particles. This review summarizes recent advances in synthesizing hydrogel microparticles using lithographic processes and highlight a number of emerging applications. We discuss advantages and limitations of current strategies, and conclude with an outlook on future trends in the field. PMID:21516212

  17. Consideration of some fundamental erosion processes encountered in hypervelocity electromagnetic propulsion

    SciTech Connect

    Buckingham, A.C.; Hawke, R.S.

    1982-09-30

    Experimental and theoretical research has been conducted jointly at the Livermore and Los Alamos National laboratories on dc electromagnetic railgun Lorentz accelerators. Pellets weighing a few grams to tens of grams have been launched at velocities up to better than 11 km/s. The research is addressed to attaining repeated launches of samples at hypervelocity in target impact experiments. In these experiments, shock-induced pressures in the tens of megabars range are obtained for high pressure equation-of-state research. Primary energy sources of the order of several hundred kJ to a MJ and induction currents of the order of 1 or more MA are necessary for these launches. Erosion and deformation of the conductor rails and the accelerated sample material are continuing problems. The heating, stress, and erosion resulting from simultaneous imposition of rail induction current, dense plasma (armature) interaction, current distribution, magnetic field stresses and projectile/rail contact friction are examined. It is found that while frictional heating and consequent sliding contact erosion are minor contributors to the overall erosion process, the same cannot be said for plasma impingement, penetration, and almost simultaneous induction current (Joule) heating.

  18. Femtosecond dynamics of fundamental reaction processes in liquids: Proton transfer, geminate recombination, isomerization and vibrational relaxation

    SciTech Connect

    Schwartz, B.J.

    1992-11-01

    The fast excited state intramolecular proton transfer of 3-hydroxyflavone is measured and effects of external hydrogen-bonding interactions on the proton transfer are studied. The proton transfer takes place in {approximately}240 fsec in nonpolar environments, but becomes faster than instrumental resolution of 110 fsec in methanol solution. The dynamics following photodissociation of CH{sub 2}I{sub 2} and other small molecules provide the first direct observations of geminate recombination. The recombination of many different photodissociating species occurs on a {approximately}350 fsec time scale. Results show that recombination yields but not rates depend on the solvent environment and suggest that recombination kinetics are dominated by a single collision with surrounding solvent cage. Studies of sterically locked phenyl-substituted butadienes offer new insights into the electronic structure and isomerization behavior of conjugated polyenes. Data show no simple correlation between hinderance of specific large amplitude motions and signatures of isomerizative behavior such as viscosity dependent excited state lifetimes, implying that the isomerization does not provide a suitable for simple condensed phase reaction rate theories. The spectral dynamics of a photochromic spiropyran indicate that recombination, isomerization and vibrational relaxation all play important roles in photoreactivity of complex molecules. The interplay of these microscopic phenomena and their effect on macroscopic properties such as photochromism are discussed. All the results indicate that the initial steps of the photochromic reaction process occur extremely rapidly. Laser system and computer codes for data analysis are discussed.

  19. Advanced Small Rocket Chambers. Basic Program and Option 2: Fundamental Processes and Material Evaluation

    NASA Technical Reports Server (NTRS)

    Jassowski, Donald M.

    1993-01-01

    Propellants, chamber materials, and processes for fabrication of small high performance radiation cooled liquid rocket engines were evaluated to determine candidates for eventual demonstration in flight-type thrusters. Both storable and cryogenic propellant systems were considered. The storable propellant systems chosen for further study were nitrogen tetroxide oxidizer with either hydrazine or monomethylhydrazine as fuel. The cryogenic propellants chosen were oxygen with either hydrogen or methane as fuel. Chamber material candidates were chemical vapor deposition (CVD) rhenium protected from oxidation by CVD iridium for the chamber hot section, and film cooled wrought platinum-rhodium or regeneratively cooled stainless steel for the front end section exposed to partially reacted propellants. Laser diagnostics of the combustion products near the hot chamber surface and measurements at the surface layer were performed in a collaborative program at Sandia National Laboratories, Livermore, CA. The Material Sample Test Apparatus, a laboratory system to simulate the combustion environment in terms of gas and material temperature, composition, and pressure up to 6 Atm, was developed for these studies. Rocket engine simulator studies were conducted to evaluate the materials under simulated combustor flow conditions, in the diagnostic test chamber. These tests used the exhaust species measurement system, a device developed to monitor optically species composition and concentration in the chamber and exhaust by emission and absorption measurements.

  20. Fundamental Analysis of Piezocatalysis Process on the Surfaces of Strained Piezoelectric Materials

    PubMed Central

    Starr, Matthew B.; Wang, Xudong

    2013-01-01

    Recently, the strain state of a piezoelectric electrode has been found to impact the electrochemical activity taking place between the piezoelectric material and its solution environment. This effect, dubbed piezocatalysis, is prominent in piezoelectric materials because the strain state and electronic state of these materials are strongly coupled. Herein we develop a general theoretical analysis of the piezocatalysis process utilizing well-established piezoelectric, semiconductor, molecular orbital and electrochemistry frameworks. The analysis shows good agreement with experimental results, reproducing the time-dependent voltage drop and H2 production behaviors of an oscillating piezoelectric Pb(Mg1/3Nb2/3)O3-32PbTiO3 (PMN-PT) cantilever in deionized water environment. This study provides general guidance for future experiments utilizing different piezoelectric materials, such as ZnO, BaTiO3, PbTiO3, and PMN-PT. Our analysis indicates a high piezoelectric coupling coefficient and a low electrical conductivity are desired for enabling high electrochemical activity; whereas electrical permittivity must be optimized to balance piezoelectric and capacitive effects. PMID:23831736

  1. 468 IEEE JOURNAL OF SELECTED TOPICS IN SIGNAL PROCESSING, VOL. 4, NO. 3, JUNE 2010 Fundamental Limit of Sample Generalized Eigenvalue

    E-print Network

    468 IEEE JOURNAL OF SELECTED TOPICS IN SIGNAL PROCESSING, VOL. 4, NO. 3, JUNE 2010 Fundamental in statistical signal processing can be succinctly formulated: given (possibly) signal bearing, -dimensional spaced signals in sensor array processing, abrupt change detection in sensor networks, and clustering

  2. Fundamental studies on ultrasonic cavitation-assisted molten metal processing of A356-nanocomposites

    NASA Astrophysics Data System (ADS)

    Liu, Xiaoda

    The usage of lightweight high-performance components is expected to increase significantly as automotive, military and aerospace industries are required to improve the energy efficiency and the performance of their products. A356, which is much lighter than steel, is an attractive replacement material. Therefore, it is of great interest to enhance its properties. There is strong evidence that the microstructure and mechanical properties can be considerably improved if nanoparticles are used as reinforcement to form metal-matrix-nano-composite (MMNC). Several recent studies revealed that ultrasonic vibration is highly efficient in dispersing nanoparticles into the melt and producing MMNC. In this thesis, a detailed analysis of the microstructure and mechanical properties is provided for an A356 alloy enhanced with Al2O 3 and SiC nanoparticles via ultrasonic processing. Each type of the nanoparticles was inserted into the A356 molten metal and dispersed by ultrasonic cavitation and acoustic streaming technology (UST) to avoid agglomeration or coalescence. The results showed that microstructures were greatly refined and with the addition of nanoparticles, tensile strength, yield strength and elongation increased significantly. SEM and EDS analyses were also performed to analyze the dispersion of nanoparticles in the A356 matrix. Since the ultrasonic energy is concentrated in a small region under the ultrasonic probe, it is difficult to ensure proper cavitation and acoustic streaming for efficient dispersion of the nanoparticles (especially in larger UST systems) without to determine the suitable ultrasonic parameters via modeling and simulation. Accordingly, another goal of this thesis was to develop well-controlled UST experiments that can be used in the development and validation of a recently developed UST modeling and simulation tool.

  3. Geology of Kentucky

    NSDL National Science Digital Library

    This website contains geologic maps of Kentucky, with a discussion of geologic time in regards to the rocks, minerals, fossils, and economic deposits found there. There are also sections that describe strata and geologic structures beneath the surface (faults, basins, and arches), the structural processes (folding and faulting) that create stratigraphic units, the geomorphology of the state, geologic information by county, a general description of geologic time, fossil, rocks, and minerals of Kentucky, and a virtual field trip through Natural Bridges State Park. Links are provided for further information.

  4. Impact, and its implications for geology

    NASA Astrophysics Data System (ADS)

    Marvin, Ursula B.

    The publication of seminal texts on geology and on meteoritics in the 1790s, laid the groundwork for the emergence of each discipline as a modern branch of science. Within the past three decades, impact cratering has become universally accepted as a process that sculptures the surfaces of planets and satellites throughout the solar system. Nevertheless, one finds in-depth discussions of impact processes mainly in books on the Moon or in surveys of the Solar System. The historical source of the separation between meteoritics and geology is easy to identify. It began with Hutton. Meteorite impact is an extraordinary event acting instantaneously from outside the Earth. It violates Hutton's principles, which were enlarged upon and firmly established as fundamental to the geological sciences by Lyell. The split between meteoritics and geology surely would have healed as early as 1892 if the investigations conducted by Gilbert (1843-1918) at the crater in northern Arizona had yielded convincing evidence of meteorite impact. The 1950s and 1960s saw a burgeoning of interest in impact processes. The same period witnessed the so-called revolution in the Earth Sciences, when geologists yielded up the idea of fixed continents and began to view the Earth's lithosphere as a dynamic array of horizontally moving plates. Plate tectonics, however, is fully consistent with the geological concepts inherited from Hutton: the plates slowly split, slide, and suture, driven by forces intrinsic to the globe.

  5. The Preliminary Processing and Geological Interpretation of Lunar Penetrating Radar Channel-1 Data from Chang'E-3

    NASA Astrophysics Data System (ADS)

    Yuan, Y.; Zhu, P.; Zhao, N.; Guo, S.; Xiao, L.; Xiao, Z.

    2014-12-01

    This is the first time to obtain the subsurface profiles using the lunar penetrating radar (LPR) on the Moon surface. Two types of antennas, channel-1 and channel-2, with different resolutions were equipped on the LPR, which detected the lunar subsurface structure with low frequency and the thickness of regolith with high frequency, respectively. We focus on the study of the lunar subsurface structure using channel-1 data. Considering the propagation characteristics of radar wave, the processing of amplitude compensation and filtering are applied to improve the imaging quality, and the processed profile clearly represents deeper than 300 meters of layered information. Based on the geological background around landing site, we present the preliminary geological interpretation for the lunar subsurface structure. More than 5 obvious reflecting events should be concerned along the track of the Yutu rover, which infer different lava sequences, including the Eratosthenian basalts, paleo-regolith formed between Eratosthenian and Imbrium, and multistage infilled lavas formed inter-layers among the Imbrium basalts.

  6. Fundamentals of Image Processing

    E-print Network

    Erdem, Erkut

    A and phase f of the corresponding sine · How can F hold both? Complex number trick! )()()( iIRF += 22 · Method 0: filter the image with eye patch Input Filtered Image ],[],[],[ , lnkmflkgnmh lk ++= What in image · Method 1: filter the image with zero-mean eye Input Filtered Image (scaled) Thresholded

  7. Fundamentals of! Image Processing!

    E-print Network

    Erdem, Erkut

    can F hold both? Complex number trick! )()()( iIRF += 22 )()( IRA +±= )( )( tan 1 R I- = We can Correlation! Slide: Hoiem! Matching with filters" · Goal: find in image! · Method 0: filter the image with eye: find in image! · Method 1: filter the image with zero-mean eye! ! Input! Filtered Image (scaled

  8. Fundamentals of Image Processing

    E-print Network

    Erdem, Erkut

    can F hold both? Complex number trick! )()()( iIRF += 22 )()( IRA +±= )( )( tan 1 R I- = We can Slide: Hoiem #12;Matching with filters · Goal: find in image · Method 0: filter the image with eye: find in image · Method 1: filter the image with zero-mean eye Input Filtered Image (scaled

  9. USGS: Geology in the Parks

    NSDL National Science Digital Library

    The US Geological Survey Geology in the Parks Web site is a cooperative project of the USGS Western Earth Surface Processes Team and the National Park Service. This extensive site covers geologic maps, plate tectonics, rocks and minerals, geologic time, US geologic provinces, park geology of the Mojave, Sunset Crater, Lake Mead, North Cascades, Death Valley, Yosemite National Park, and much more. Descriptions, graphics, photographs, and animations all contribute to this informative and interesting Web site making it a one stop, all encompassing, resource for everything geology and US national park related.

  10. GIS-project: geodynamic globe for global monitoring of geological processes

    NASA Astrophysics Data System (ADS)

    Ryakhovsky, V.; Rundquist, D.; Gatinsky, Yu.; Chesalova, E.

    2003-04-01

    A multilayer geodynamic globe at the scale 1:10,000,000 was created at the end of the nineties in the GIS Center of the Vernadsky Museum. A special soft-and-hardware complex was elaborated for its visualization with a set of multitarget object directed databases. The globe includes separate thematic covers represented by digital sets of spatial geological, geochemical, and geophysical information (maps, schemes, profiles, stratigraphic columns, arranged databases etc.). At present the largest databases included in the globe program are connected with petrochemical and isotopic data on magmatic rocks of the World Ocean and with the large and supperlarge mineral deposits. Software by the Environmental Scientific Research Institute (ESRI), USA as well as ArcScan vectrorizator were used for covers digitizing and database adaptation (ARC/INFO 7.0, 8.0). All layers of the geoinformational project were obtained by scanning of separate objects and their transfer to the real geographic co-ordinates of an equiintermediate conic projection. Then the covers were projected on plane degree-system geographic co-ordinates. Some attributive databases were formed for each thematic layer, and in the last stage all covers were combined into the single information system. Separate digital covers represent mathematical descriptions of geological objects and relations between them, such as Earth's altimetry, active fault systems, seismicity etc. Some grounds of the cartographic generalization were taken into consideration in time of covers compilation with projection and co-ordinate systems precisely answered a given scale. The globe allows us to carry out in the interactive regime the formation of coordinated with each other object-oriented databases and thematic covers directly connected with them. They can be spread for all the Earth and the near-Earth space, and for the most well known parts of divergent and convergent boundaries of the lithosphere plates. Such covers and time series reflect in diagram form a total combination and dynamics of data on the geological structure, geophysical fields, seismicity, geomagnetism, composition of rock complexes, and metalloge-ny of different areas on the Earth's surface. They give us possibility to scale, detail, and develop 3D spatial visualization. Information filling the covers could be replenished as in the existing so in newly formed databases with new data. The integrated analyses of the data allows us more precisely to define our ideas on regularities in development of lithosphere and mantle unhomogeneities using some original technologies. It also enables us to work out 3D digital models for geodynamic development of tectonic zones in convergent and divergent plate boundaries with the purpose of integrated monitoring of mineral resources and establishing correlation between seismicity, magmatic activity, and metallogeny in time-spatial co-ordinates. The created multifold geoinformation system gives a chance to execute an integral analyses of geoinformation flows in the interactive regime and, in particular, to establish some regularities in the time-spatial distribution and dynamics of main structural units in the lithosphere, as well as illuminate the connection between stages of their development and epochs of large and supperlarge mineral deposit formation. Now we try to use the system for prediction of large oil and gas concentration in the main sedimentary basins. The work was supported by RFBR, (grants 93-07-14680, 96-07-89499, 99-07-90030, 00-15-98535, 02-07-90140) and MTC.

  11. Image Gallery for Geology

    NSDL National Science Digital Library

    Allen Glazner

    These images of geologic phenomena are used to supplement introductory geology classes at the University of North Carolina at Chapel Hill. The images are categorized under plutonic, volcanic and sedimentary rocks; structural geology; weathering; and coastlines. There are photographs of different kinds of volcanoes; lavas and pyroclastic rocks; volcanic hazards; different types of sedimentary rocks and sedimentary structures; folds and faults; beach processes; and barrier islands.

  12. Thermal Conduction - A Tool for Exploring Geological Processes on the Earth and Other Bodies in our Solar System

    NSDL National Science Digital Library

    Eric Grosfils

    Thermal conduction is a fundamental physical process, one which controls many aspects of the volcanic and tectonic evolution of bodies within our solar system. Using transmission of thermal energy through the crust of the Earth as an initial, physically intuitive conceptual model, the module's background material will (a) help students deduce the thermal conduction equation-a second order differential which can be constructed from first principles, (b) evaluate volume-adjusted conduction incorporating internal heat generation and temperature change, and (c) explore special forms of the equation such as steady state conduction and thermal diffusion.

  13. Geologic Explorations

    NSDL National Science Digital Library

    Alec Bodzin

    2002-04-01

    Geologic Explorations allows learners to explore a variety of unique geological formations of Utah using Quicktime Virtual Reality (QTVR) panoramas and digital still imagery. Spectacular panoramas and striking images capture Utah's unique geology and invite students to explore and learn interesting facts and concepts central to the study of geology.

  14. Geology of the Colorado Plateau

    NSDL National Science Digital Library

    Colorado Plateau Field Institute

    This web page provides a general description of the geology of the Colorado Plateau. Topics include information about the various geologic environments and processes active during the Precambrian and the Paleozoic, Mesozoic and Cenozoic Eras.

  15. Statistical pre-processing and analyses of hydro-meteorological time series in a geologic clay site (methodology and first results for Mont Terri’s PP experiment)

    NASA Astrophysics Data System (ADS)

    Fatmi, H.; Ababou, R.; Matray, J. M.

    This article presents a set of statistical methods for pre-processing (or pre-conditioning) and analyzing multivariate hydro-geologic time series, such as pore pressures and atmospheric pressure (temporal structures). The pre-processing methods are necessary to enhance or complete the signals due to defects in the observed time series (data gaps, spurious values, variable time steps). The statistical analyses aim, in fine, at characterizing the hydraulic behaviour of a clayey formation in the context of deep geologic disposal of radioactive waste. Pore water and atmospheric pressure time series from the Mont Terri rock laboratory (BPP-1 borehole) are taken as an example.

  16. Geologic Maps

    NSDL National Science Digital Library

    Geologic Maps are unique in that they show the distribution of geologic features on a landscape through specific symbols and colors. The United States Geological Survey's (USGS) site Geologic Maps provides visitors with a good introduction to these concepts, which include the unique features of a geologic map; the meaning of their lines, colors, and symbols; the location of faults; and more. Anyone working with geologic maps or just interested in learning a little about cartography or geology will find this site easy to explore and full of good information.

  17. In Situ Optical Observation of High-Temperature Geological Processes With the Moissanite Cell

    Microsoft Academic Search

    N. Walte; H. Keppler

    2005-01-01

    A major drawback of existing techniques in experimental earth and material sciences is the inability to observe ongoing high-temperature processes in situ during an experiment. Examples for important time-dependent processes include the textural development of rocks and oxide systems during melting and crystallization, solid-state and melt-present recrystallization and Ostwald ripening, and bubble nucleation and growth during degassing of glasses and

  18. Results From an International Simulation Study on Couples Thermal, Hydrological, and Mechanical (THM) Processes Near Geological Nuclear Waste Repositories

    SciTech Connect

    J. Rutqvist; D. Barr; J.T. Birkholzer; M. Chijimatsu; O. Kolditz; Q. Liu; Y. Oda; W. Wang; C. Zhang

    2006-08-02

    As part of the ongoing international DECOVALEX project, four research teams used five different models to simulate coupled thermal, hydrological, and mechanical (THM) processes near waste emplacement drifts of geological nuclear waste repositories. The simulations were conducted for two generic repository types, one with open and the other with back-filled repository drifts, under higher and lower postclosure temperatures, respectively. In the completed first model inception phase of the project, a good agreement was achieved between the research teams in calculating THM responses for both repository types, although some disagreement in hydrological responses is currently being resolved. In particular, good agreement in the basic thermal-mechanical responses was achieved for both repository types, even though some teams used relatively simplified thermal-elastic heat-conduction models that neglected complex near-field thermal-hydrological processes. The good agreement between the complex and simplified process models indicates that the basic thermal-mechanical responses can be predicted with a relatively high confidence level.

  19. Layer Cake Geology

    NSDL National Science Digital Library

    John Wagner

    This classroom activity uses a cake to demonstrate geologic processes and introduce geologic terms. Students will learn how folds and faults occur, recognize the difference in behavior between brittle and ductile rocks, and attempt to predict structures likely to result from application of various forces to layered rocks. They will also attempt to interpret 'core samples' to determine subsurface rock structure.

  20. Limitations on squeezing and formation of the superposition of two macroscopically distinguishable states at fundamental frequency in the process of second harmonic generation

    NASA Technical Reports Server (NTRS)

    Nikitin, S. P.; Masalov, A. V.

    1992-01-01

    The results of numerical simulations of quantum state evolution in the process of second harmonic generation (SHG) are discussed. It is shown that at a particular moment of time in the fundamental mode initially coherent state turns into a superposition of two macroscopically distinguished states. The question of whether this superposition exhibits quantum interference is analyzed.

  1. Dynamics of present-day geological processes from remotely sensed data

    NASA Astrophysics Data System (ADS)

    Kats, Ia. G.; Poletaev, A. I.; Rumiantseva, E. F.; Tevelev, A. V.

    Remotely sensed data on the dynamics of present-day exogenous and endogenous processes occurring at different depths and with different intensity and manifestations are discussed. Attention is given to the processes of continental-sediment accumulation at the Tedzhen and Murgab River deltas and the Amu-Daria River bed, deformation processes occurring in the Pamir-Alai region, and the deep-lying interactions of the Iranian and Turan platforms. It is noted that the presence of high-degree correlations among the lineament fields of the individual subregions of the Pamir-Alai region, the Gissar-Alai region, and the region of northern Pamir suggests that these regions belong to a single elongated dynamic zone.

  2. The Large Impact Process Inferred from the Geology of Lunar Multiring Basins

    NASA Technical Reports Server (NTRS)

    Spudis, Paul D.

    1994-01-01

    The study of the geology of multiring impact basins on the Moon over the past ten years has given us a rudimentary understanding of how these large structures have formed and evolved on the Moon and other bodies. Two-ring basins on the Moon begin to form at diameters of about 300 km; the transition diameter at which more than two rings appear is uncertain, but it appears to be between 400 and 500 km in diameter. Inner rings tend to be made up of clusters or aligned segments of massifs and are arranged into a crudely concentric pattern; scarp-like elements may or may not be present. Outer rings are much more scarp-like and massifs are rare to absent. Basins display textured deposits, interpreted as ejecta, extending roughly an apparent basin radius exterior to the main topographic rim. Ejecta may have various morphologies, ranging from wormy and hummocky deposits to knobby surfaces; the causes of these variations are not known, but may be related to the energy regime in which the ejecta are deposited. Outside the limits of the textured ejecta are found both fields of satellitic craters (secondaries) and light plains deposits. Impact melt sheets are observed on the floors of relatively unflooded basins. Samples of impact melts from lunar basins have basaltic major-element chemistry, characterized by K, rare-earth elements (REE), P, and other trace elements of varying concentration (KREEP); ages are between 3.8 and 3.9 Ga. These lithologies cannot be produced through the fusion of known pristine (plutonic) rock types, suggesting the occurrence of unknown lithologies within the Moon. These melts were probably generated at middle to lower crustal levels. Ejecta compositions, preservation of pre-basin topography, and deposit morphologies all indicate that the excavation cavity of multiring basins is between about 0.4 and 0.6 times the diameter of the apparent crater diameter. Basin depths of excavation can be inferred from the composition of basin ejecta. A variety of mechanisms has been proposed to account for the formation of basin rings but none of them are entirely plausible. Mechanisms can be divided into two broad groups: (1) forcible uplift due to fluidization of the target; (2) concentric, brittle, fracturing and failure of the target, on regional (megaterraces) to global scales (lithospheric fracturing). Most basin rings are spaced at a constant factor on all planets. Evidence supports divergent ringforming models, so it may be that the ring-locating mechanism differs from the ring-forming mechanism. Thus, large-scale crustal foundering (megaterracing) could occur along concentric zones of weakness created by some type of resonant wave mechanism (fluidization and uplift); such immediate crustal adjustment could then be followed by long-term adjustment of the fractured lithosphere.

  3. Processes of lunar crater degradation: Changes in style with geologic time

    Microsoft Academic Search

    James W. Head

    1975-01-01

    Lunar crater degradation can be divided into two time periods based on differing styles and rates of crater degradation processes.\\u000a Comparison of lunar radiometric age scales and the relative degradation of crater morphologic features for craters larger\\u000a than about 5 km diam shows that Period I, prior to about 3.85–3.95 b.y. ago, is characterized by a high influx rate and

  4. International Geology

    ERIC Educational Resources Information Center

    Hoover, Linn

    1977-01-01

    Briefly discusses recent international programs in various areas of geology, including land-use problems, coping with geological hazards, and conserving the environment while searching for energy and mineral resources. (MLH)

  5. Environmental Geology

    ERIC Educational Resources Information Center

    Dunn, James R.

    1977-01-01

    Discusses ways that geologic techniques can be used to help evaluate our environment, make economic realities and environmental requirements more compatible, and expand the use of geology in environmental analyses. (MLH)

  6. Archeological Geology

    ERIC Educational Resources Information Center

    Rapp, George

    1977-01-01

    Describes the rapid expansion of archeological geology, especially in the area of archeological excavations, where geologists use dating techniques and knowledge of geological events to interpret archeological sites. (MLH)

  7. In Situ Optical Observation of High-Temperature Geological Processes With the Moissanite Cell

    NASA Astrophysics Data System (ADS)

    Walte, N.; Keppler, H.

    2005-12-01

    A major drawback of existing techniques in experimental earth and material sciences is the inability to observe ongoing high-temperature processes in situ during an experiment. Examples for important time-dependent processes include the textural development of rocks and oxide systems during melting and crystallization, solid-state and melt-present recrystallization and Ostwald ripening, and bubble nucleation and growth during degassing of glasses and melts. The investigation of these processes by post-mortem analysis of a quenched microstructure is time consuming and often unsatisfactory. Here, we introduce the moissanite cell that allows optical in situ observation of long-term experiments at high temperatures. Moissanite is a transparent gem-quality type of SiC that is characterized by its hardness and superior chemical and thermal resistance. Two moissanite windows with a thickness and diameter of several millimeters are placed into sockets of fired pyrophyllite and fixed onto two opposite metal plates. The sockets are wrapped with heating wire and each window is connected to a thermocouple for temperature control. The sample is placed directly between the moissanite windows and the cell is assembled similarly to a large diamond anvil cell. In situ observation of the sample is done with a microscope through observation windows and movies are recorded with an attached digital camera. Our experiments with the new cell show that temperatures above 1200°C can be maintained and observed in a sample for several days without damaging the cell nor the windows. Time-lapse movies of melting and crystallizing natural and synthetic rocks and of degassing glasses and melts will be presented to show the potential of the new technique for experimental earth and material science.

  8. Quaternary geology and sedimentary processes in the vicinity of Six Mile Reef, eastern Long Island Sound

    USGS Publications Warehouse

    Poppe, L.J.; Williams, S.J.; Moser, M.S.; Forfinski, N.A.; Stewart, H.F.; Doran, E.F.

    2008-01-01

    Six Mile Reef, a sandy, 22-m-high shoal trending east-west and located about 7.8 km off the Connecticut coast, has a core of postglacial marine deltaic deposits mantled by tidally reworked modern sediments. Sedimentary environments off the eastern end of the shoal are characterized by processes associated with long-term erosion or nondeposition, a mobile-sediment-limited seafloor armored by gravelly sand, and scattered elongate fields of barchanoid sand waves. The barchanoid waves reach amplitudes of 20 m, are concave westward, and occur in individual and coalesced forms that become progressively more complex westward. The seafloor on and adjacent to the shoal is characterized by processes associated with coarse bedload transport and covered primarily with asymmetrical transverse sand waves. The transverse waves exceed 8 m in amplitude, have slip faces predominantly oriented to the west and southwest, and have straight, slightly sinuous, and curved crests. Megaripples, which mimic the asymmetry of the sand waves, are commonly present on stoss slopes and in troughs; current ripples are ubiquitous. The amplitude and abundance of large bedforms decrease markedly westward of Six Mile Reef. The seabed there is covered with small, degraded ripples, reflecting lower-energy environments and processes associated with sorting and reworking of seafloor sediments. Megaripples and current ripples on the sand waves suggest that transport is active and that the bedforms are propagating under the present hydraulic regime. Net bedload sediment transport is primarily to the west, as evidenced by textural trends of surficial sediments, orientation of the barchanoid waves, and asymmetry of the transverse waves and of the scour marks around bedrock outcrops, boulders, and shipwrecks. One exception occurs at the western tip of the shoal, where sand-wave morphology indicates long-term eastward transport, suggesting that countercurrents in this area shape the shoal and are important to its maintenance.

  9. Structural Geology

    NSDL National Science Digital Library

    Created by the University of Nebraska-Lincoln, this site describes the basics of structural geology with text and images. The page includes the discussion of stress, strain, strike and dip, faults, folds, mountain building, erosion, economic geology, and environmental geology. This is a nice introduction to the basic topics in geology. Images from the field help to enhance the topics on the site. Instructors can use this resource to help create or simply enhance their curriculum.

  10. Genesis of karren in Kentucky Lake, Tennessee: Interaction of geologic structure, weathering processes, and bioerosion

    SciTech Connect

    Gibson, M.A.; Smith, W.L. (Univ. of Tennessee, Martin, TN (United States))

    1993-03-01

    While karst features formed along marine coastlines are commonly reported, shoreline karst features produced within lacustrine systems have received little attention. The shoreline of Bond Island'' in Kentucky Lake has evolved a distinctive karren geomorphology not recognized elsewhere in the lake. The karren consist of well-developed clint and grike topography, trench formation, solution pits, flutes, and runnels, and pit and tunnel development. Two processes are responsible for the karren. First, freshwater dissolution and wave action on structurally fractured Decatur Limestone (Silurian) mechanically and chemically weaken the entire exposed surface. Second, a seasonal cycle of winter freeze-thaw and frost wedging followed by spring bioerosion overprints the first set of processes. Bioerosion by chemical dissolution involving a complex association of predominantly chironomids, algae, fungi, and bryozoa results in preferential dissolution along joints, stylolites, and bedding planes to form shallow spindle-shaped solution pits over the entire surface and sides of the karren. The solution pits average 1 cm length by 0.4 cm depth densely covering rock surfaces. This study suggests that seasonal bioerosion may constitute a more important geomorphic factor in lacustrine systems than previously recognized.

  11. Geological Time

    NSDL National Science Digital Library

    "Why do engineers need to know about geologic time?" That question is answered in this resource from the University of Saskatchewan's Department of Civil and Geological Engineering. Provided here is a discussion of the concepts of geological time; relative dating methods, such as correlation; and absolute dating methods, such as radiometric methods. Diagrams and charts are included to demonstrate these complex concepts.

  12. Occurrence of native silicon in a fulgurite and implications of extreme reduction as a geologic process

    SciTech Connect

    Essene, E.J.

    1985-01-01

    Native silicon was discovered in fulgurite recently formed on till near Winan's Lake, Michigan. Further examination of immiscible metallic globules in fulgurite glass reported by Essene and Fisher has revealed native silicon as euhedral crystals in metal and intergrown with SiO/sub 2/-rich glass in the fulgurite matrix. Although difficult to distinguish from moissanite (SiC), sinoite (Si/sub 2/N/sub 2/O) or silica (SiO/sub 2/) on the microprobe, the identity of silicon was confirmed by scans showing no N, C or O at 0.2% detection limits. X-ray powder data revealed the major peaks for Si, and confirmed its existence as a mineral. The native Si occurs in a highly reducing assemblage with Fe/sub 3/Si/sub 7/, FeSi, FeTiP and more rarely Au, Ag that unmixed as metallic liquid from silicate liquid at T > 2100/sup 0/K during a lightning strike. This remarkable process of reduction may also occur during other ultra-high temperature phenomena such as (extra)terrestrial meteoritic and cometary impacts, or even atomic-bomb blasts. Lightning strikes possibly involving carbon compounds in primitive stellar nebulae may have produced similar reduction. Asteroidal impacts may also yield similar results and impact glasses should be searched for highly reduced metals, carbides and silicides. Fulgurite and impact events may also be recorded by persistent reports of other highly reduced minerals, such as SiC, Al, Cr, Cr/sub 2/C, TaC, or Mg/sub 2/Si. Their identity as minerals should not be discounted a priori unless such ultra-high temperature events can be conclusively rejected.

  13. Discrete fracture modeling of hydro-mechanical damage processes in geological systems

    NASA Astrophysics Data System (ADS)

    Kim, K.; Rutqvist, J.; Houseworth, J. E.; Birkholzer, J. T.

    2014-12-01

    This study presents a modeling approach for investigating coupled thermal-hydrological-mechanical (THM) behavior, including fracture development, within geomaterials and structures. In the model, the coupling procedure consists of an effective linkage between two codes: TOUGH2, a simulator of subsurface multiphase flow and mass transport based on the finite volume approach; and an implementation of the rigid-body-spring network (RBSN) method, a discrete (lattice) modeling approach to represent geomechanical behavior. One main advantage of linking these two codes is that they share the same geometrical mesh structure based on the Voronoi discretization, so that a straightforward representation of discrete fracture networks (DFN) is available for fluid flow processes. The capabilities of the TOUGH-RBSN model are demonstrated through simulations of hydraulic fracturing, where fluid pressure-induced fracturing and damage-assisted flow are well represented. The TOUGH-RBSN modeling methodology has been extended to enable treatment of geomaterials exhibiting anisotropic characteristics. In the RBSN approach, elastic spring coefficients and strength parameters are systematically formulated based on the principal bedding direction, which facilitate a straightforward representation of anisotropy. Uniaxial compression tests are simulated for a transversely isotropic material to validate the new modeling scheme. The model is also used to simulate excavation fracture damage for the HG-A microtunnel in the Opalinus Clay rock, located at the Mont Terri underground research laboratory (URL) near Saint-Ursanne, Switzerland. The Opalinus Clay has transversely isotropic material properties caused by natural features such as bedding, foliation, and flow structures. Preferential fracturing and tunnel breakouts were observed following excavation, which are believed to be strongly influenced by the mechanical anisotropy of the rock material. The simulation results are qualitatively representative of the nonuniform fracture patterns observed in the HG-A microtunnel.

  14. Capacitor fundamentals

    Microsoft Academic Search

    W. J. Sarjeant; James Clerk Maxwell

    1989-01-01

    In this review of capacitor fundamentals, the author attempts to clarify the modes of operation of the broad spectrum of capacitors, including paper\\/polymeric films, electrolytics, and ceramics. How each class of capacitor performs in both low- and high-power electronics is discussed in detail, with emphasis upon delineating those factors affecting life, reliability, maintainability, and environmental compatibility of systems in which

  15. fundamental communication

    E-print Network

    Shor, Peter W.

    Quantum Channels Peter Shor MIT Cambridge, MA 1 #12; Claude Shannon, 1948 The fundamental problem than a number of special cases. 3 #12; Shannon Shannon's 1948 paper ``A mathematical theory is the Shannon entropy of the eigenvalues. (Recall Tr# = 1 = # i # i .) You can ask: is this the right definition

  16. Isotope Tracer Studies of Diffusion in Sillicates and of Geological Transport Processes Using Actinide Elements

    SciTech Connect

    Wasserburg, Gerald J

    2008-07-31

    The objectives were directed toward understanding the transport of chemical species in nature, with particular emphasis on aqueous transport in solution, in colloids, and on particles. Major improvements in measuring ultra-low concentrations of rare elements were achieved. We focused on two areas of studies: (1) Field, laboratory, and theoretical studies of the transport and deposition of U, Th isotopes and their daughter products in natural systems; and (2) Study of calcium isotope fractionation effects in marine carbonates and in carbonates precipitated in the laboratory, under controlled temperature, pH, and rates of precipitation. A major study of isotopic fractionation of Ca during calcite growth from solution has been completed and published. It was found that the isotopic shifts widely reported in the literature and attributed to biological processes are in fact due to a small equilibrium fractionation factor that is suppressed by supersaturation of the solution. These effects were demonstrated in the laboratory and with consideration of the solution conditions in natural systems, where [Ca{sup 2+}] >> [CO{sub 3}{sup 2-}] + [HCO{sub 3}{sup -}]. The controlling rate is not the diffusion of Ca, as was earlier proposed, but rather the rate of supply of [CO{sub 3}{sup 2-}] ions to the interface. This now opens the issues of isotopic fractionation of many elements to a more physical-chemical approach. The isotopic composition of Ca {Delta}({sup 44}Ca/{sup 40}Ca) in calcite crystals has been determined relative to that in the parent solutions by TIMS using a double spike. Solutions were exposed to an atmosphere of NH{sub 3} and CO{sub 2}, provided by the decomposition of (NH4)2CO3. Alkalinity, pH, and concentrations of CO{sub 3}{sup 2-}, HCO{sub 3}{sup -}, and CO{sub 2} in solution were determined. The procedures permitted us to determine {Delta}({sup 44}Ca/{sup 40}Ca) over a range of pH conditions, with the associated ranges of alkalinity. Two solutions with greatly different Ca concentrations were used, but, in all cases, the condition [Ca] >> [CO{sub 3}{sup 2-}] was met. A wide range in {Delta}({sup 44}Ca/{sup 40}Ca) was found for the calcite crystals, extending from 0.04 {+-} 0.13 to -1.34 {+-} 0.15 {per_thousand}, generally anticorrelating with the amount of Ca removed from the solution. The results show that {Delta}({sup 44}Ca/{sup 40}Ca) is a linear function of the saturation state of the solution with respect to calcite ({Omega}). The two parameters are very well correlated over a wide range in {Omega} for each solution with a given [Ca]. Solutions, which were vigorously stirred, showed a much smaller range in {Delta}({sup 44}Ca/{sup 40}Ca) and gave values of -0.42 {+-} 0.14 {per_thousand}, with the largest effect at low {Omega}. It is concluded that the diffusive flow of CO{sub 3}{sup 2-} into the immediate neighborhood of the crystal-solution interface is the rate-controlling mechanism and that diffusive transport of Ca{sup 2+} is not a significant factor. The data are simply explained by the assumptions that: (a) the immediate interface of the crystal and the solution is at equilibrium with {Delta}({sup 44}Ca/{sup 40}Ca) {approx} -1.5 {+-} 0.25 {per_thousand}, and (b) diffusive inflow of CO{sub 3}{sup 2-} causes supersaturation, thus precipitating Ca from the regions, exterior to the narrow zone of equilibrium. We consider this model to be a plausible explanation of the available data reported in the literature. The well-resolved but small and regular isotope fractionation shifts in Ca are thus not related to the diffusion of very large hydrated Ca complexes, but rather due to the ready availability of Ca in the general neighborhood of the crystal solution interface. The largest isotopic shift which occurs is a small equilibrium effect which is then subdued by supersaturation precipitation for solutions where [Ca{sup 2+}] >> [CO{sub 3}{sup 2-}] + [HCO{sub 3}{sup -}]. It is shown that there is a clear temperature dependence of the net isotopic shifts, which is simply due to changes in {Omega}

  17. Measuring Geologic Time on Mars

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Recent images from Mars show compelling evidence of near-surface flowing water, aeolian activity slope processes, and ice cap evolution that underscores the dynamic geologic history of the planet. Establishing an accurate chronology for Martian planetary features is critical for addressing fundamental questions about the evolution of the planet's surface and atmosphere and the differentiation of its interior. For example, how long was standing water on the surface? If life did evolve on Mars, did it occur before or after the evolution of life on Earth? These are arguably some of the most profound questions currently being asked by the planetary science community. Yet answers will not be forthcoming without an absolute chronology of Mars history, enabling the construction of a timescale comparable to Earth's. Discussion of methods for establishing such a chronology is particularly timely in light of new missions to Mars that are being planned to return in situ measurements or samples to Earth.

  18. Research on three-dimensional geological model construction and application of the open pit mine based on sections

    Microsoft Academic Search

    Wang Jinjin; Liu Guangwei; Bai Runcai; Zhao Hao

    2010-01-01

    Three-dimensional geological modeling (3DGM) is one of key issues to be solved in the three-dimensional geographic information system (3DGIS) and virtual mine technical research. Mine 3D geological modeling and visualization play a very significant role in the process of the mine exporting, designing and developing. Regarding the information of drilling hole and section charts as fundamental data, the author presents

  19. Geology Field Trips as Performance Evaluations

    ERIC Educational Resources Information Center

    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…

  20. Geologic influences on the in situ processing of tar sand at the Northwest Asphalt Ridge deposit, Utah

    SciTech Connect

    Sinks, D.J.

    1985-01-01

    The Laramie Energy Technology Center, Department of Energy, completed three in situ oil recovery field experiments, two combustion and one steamflood, in tar sand at Northwest Asphalt Ridge, Utah. Inadequate resource and site characterization prior to the field experiments contributed to process design and operation problems. The 10-acre field site is part of the Sohio Shale Oil Co. D tract located west of Vernal, Uintah County. The target zone, the middle portion of the Cretaceous Rim Rock Sandstone of the Mesaverde Group, varied from 300 to 500 feet deep. From petrographic analyses of the target zone, this portion is classified as a moderately sorted litharenite with an average visible porosity of 18%. Dominant constituents include quartz, rock fragments, chert, feldspars and clay minerals. X-ray analyses of selected core samples from the Rim Rock and Asphalt Ridge Sandstones indicate the presence of quartz, calcite, dolomite, ankerite, microcline, orthoclase, anorthite, kaolinite and muscovite. Carbonate mineral species were present only in the lower Rim Rock and Asphalt Ridge Sandstones. Reservoir characteristics of the target zone which adversely affected the field experiments include faulting at all three experiment areas, lateral and vertical heterogeneities of permeability and porosity, inadequate target zone confinement, rough surface texture of clastic grains, and oil-wet grains. Favorable target zone characteristics include high quartz content; absence of carbonates; lack of clay minerals bridging and cementing pore spaces; and sufficient porosity, initial oil saturation and overburden. Recommended geologic evaluation methods to aid in the identification of potentially suitable resources and sites for in situ oil recovery from tar sands include seismic surveys; well logging; coring and core analyses; petrographic, binocular, and scanning electron microscopy; and x-ray analyses. 54 references, 25 figures, 8 tables.

  1. Utah Geology

    NSDL National Science Digital Library

    Utah Geological Survey's Web site, Utah Geology, offers a variety of interesting geological information about the state. Good descriptions, illustrations, and photographs can be accessed on earthquakes and hazards, dinosaurs and fossils, rocks and minerals, oil and energy, and more. For example, the Rocks and Minerals page contains everything from how to stake a mining claim to downloadable summaries of mineral activity in the state. There is quite a bit of information within the site, and anyone interested in geology will find themselves exploring these pages for quite a while.

  2. Side-scan sonar along the north wall of the Hess Deep Rift: Processing, texture analysis, and geologic ground truth on an oceanic escarpment

    NASA Astrophysics Data System (ADS)

    Hurst, Stephen D.; Karson, Jeffrey A.

    2004-02-01

    Side-scan sonar data collected along the steep, faulted north wall of the Hess Deep Rift provide images of a cross section of the upper oceanic crust. These data are integrated with ground truth from the submersible Alvin and the Argo II remotely operated vehicle (ROV) to evaluate faulting and mass wasting associated with the opening of the rift and to help trace geologic contacts between widely spaced dives and ROV surveys. Initial shipboard and subsequently processed data show excellent backscatter returns with well-imaged textures and distinctive patterns corresponding to specific rock units and surficial deposits. Four backscatter textures are widely developed and found to correspond to outcrops of basaltic lavas, outcrops of sheeted dikes and gabbroic rocks, surficial talus and rubble deposits, and pelagic sedimentary material. Using test areas identified by Alvin dives, the side-scan sonar data were processed to automatically classify the backscatter returns in terms of major rock units. The resultant processed image is used for further manual and computer-aided classification of the scarp geology. These techniques are evaluated for mapping the geology in rugged terrains similar to the steep walls of Hess Deep Rift.

  3. Integration of geological remote-sensing techniques in subsurface analysis

    USGS Publications Warehouse

    Taranik, James V.; Trautwein, Charles M.

    1976-01-01

    Geological remote sensing is defined as the study of the Earth utilizing electromagnetic radiation which is either reflected or emitted from its surface in wavelengths ranging from 0.3 micrometre to 3 metres. The natural surface of the Earth is composed of a diversified combination of surface cover types, and geologists must understand the characteristics of surface cover types to successfully evaluate remotely-sensed data. In some areas landscape surface cover changes throughout the year, and analysis of imagery acquired at different times of year can yield additional geological information. Integration of different scales of analysis allows landscape features to be effectively interpreted. Interpretation of the static elements displayed on imagery is referred to as an image interpretation. Image interpretation is dependent upon: (1) the geologist's understanding of the fundamental aspects of image formation, and (2.) his ability to detect, delineate, and classify image radiometric data; recognize radiometric patterns; and identify landscape surface characteristics as expressed on imagery. A geologic interpretation integrates surface characteristics of the landscape with subsurface geologic relationships. Development of a geologic interpretation from imagery is dependent upon: (1) the geologist's ability to interpret geomorphic processes from their static surface expression as landscape characteristics on imagery, (2) his ability to conceptualize the dynamic processes responsible for the evolution 6f interpreted geologic relationships (his ability to develop geologic models). The integration of geologic remote-sensing techniques in subsurface analysis is illustrated by development of an exploration model for ground water in the Tucson area of Arizona, and by the development of an exploration model for mineralization in southwest Idaho.

  4. Geologic analyses of LANDSAT-1 multispectral imagery of a possible power plant site employing digital and analog image processing. [in Pennsylvania

    NASA Technical Reports Server (NTRS)

    Lovegreen, J. R.; Prosser, W. J.; Millet, R. A.

    1975-01-01

    A site in the Great Valley subsection of the Valley and Ridge physiographic province in eastern Pennsylvania was studied to evaluate the use of digital and analog image processing for geologic investigations. Ground truth at the site was obtained by a field mapping program, a subsurface exploration investigation and a review of available published and unpublished literature. Remote sensing data were analyzed using standard manual techniques. LANDSAT-1 imagery was analyzed using digital image processing employing the multispectral Image 100 system and using analog color processing employing the VP-8 image analyzer. This study deals primarily with linears identified employing image processing and correlation of these linears with known structural features and with linears identified manual interpretation; and the identification of rock outcrops in areas of extensive vegetative cover employing image processing. The results of this study indicate that image processing can be a cost-effective tool for evaluating geologic and linear features for regional studies encompassing large areas such as for power plant siting. Digital image processing can be an effective tool for identifying rock outcrops in areas of heavy vegetative cover.

  5. North Cascades Geology: Geologic Time

    NSDL National Science Digital Library

    This article describes the period of geologic time spanned by the rocks of the North Cascades area of Washington. Users can access a simplified geologic time scale that provides links to geologic events in the North Cascades region. These include the deposition of various terranes, periods of intrusion and metamorphism, the beginning of the Cascade volcanic arc, and periods of major glaciation. Links to related materials are also provided.

  6. Geological gyrocompass

    NASA Astrophysics Data System (ADS)

    McKeown, M. H.; Beason, S. C.

    1988-08-01

    The geological gyrocompass is an accurate, portable instrument useful for geologic mapping and surveying which employs an aircraft gyrocompass, strike reference bars, a pair of sights and levelling devices for horizontally levelling the instrument. A clinometer graduated in degrees indicates the dip of the surface being measured.

  7. Yosemite Geology

    NSDL National Science Digital Library

    The National Park Service maintains the Yosemite National Park Web site and the corresponding Geology page. This Web site gives an overview of the geologic history of the site, tells how the Sierra Nevada range formed, explains the basics of granitic rock, shows how glaciers carved out the canyons, and much more.[JAB

  8. Driver's various information process and multi-ruled decision-making mechanism: a fundamental of intelligent driving shaping model

    Microsoft Academic Search

    Wuhong Wang; Yan Mao; Jing Jin; Xiao Wang; Hongwei Guo; Xuemei Ren; Katsushi Ikeuchi

    2011-01-01

    The most difficult but important problem in advance driver assistance system development is how to measure and model the behavioral response of drivers with focusing on the cognition process. This paper describes driver's deceleration and acceleration behavior based on driving situation awareness in the car–following process, and then presents several driving models for analysis of driver's safety approaching behavior in

  9. The encyclopedia of applied geology

    SciTech Connect

    Finkl, C.W.

    1984-01-01

    This compendium of engineering geology data includes contributions by experts from many countries. Topics center around the field of engineering geology, with special focus on landscapes, earth materials, and the ''management'' of geological processes. How to use geology to serve man is given particular attention. More than 80 entries deal with hydrology, rock structure monitoring, soil mechanics, and engineering geology. Facts are provided on earth science information and sources, electrokinetics, forensic geology, geogryology, nuclear plant siting, photogrammetry, tunnels and tunneling, urban geomorphology, and well data systems. This guide explains the geology of alluvial plains, arid lands, beaches and coasts, delataic plains, cold regions, glacial landscapes, and urban environments. Detailed analyses are given of the geotechnical properties of caliche, clay, duricrust, soil, laterite, marine sediments, and rocks.

  10. Digital Geology of Idaho

    NSDL National Science Digital Library

    2012-02-17

    If you have ever wanted to learn about the geology of Idaho, this site is a great way to explore everything from Coeur d'Alene to the Sawtooth Mountains. This digital version of a course offered at Idaho State University systematically divides Idaho geology into a set of different teaching modules. The modules cover topics like the Idaho Batholith, the Columbia River Basalts, and the Lake Bonneville Flood. Each module contains maps, charts, diagrams, and photographs that illuminate the various geological processes that have formed, and continue to form, in each region of the state. Many of the modules also have fly-throughs that superimpose color-coded geology on 3-D topographic maps to provide a graphic visualization Idaho's rivers. Additionally, the site contains slide shows and a set of teaching exercises.

  11. Dissolved Organic Carbon Concentrations in Tempe Town Lake: biogDissolved Organic Carbon Concentrations in Tempe Town Lake: biogeochemical & hydrologic processeseochemical & hydrologic processes 1Department of Geological Sciences, 871404, Arizona State Un

    E-print Network

    Hall, Sharon J.

    Dissolved Organic Carbon Concentrations in Tempe Town Lake: biogDissolved Organic Carbon Concentrations in Tempe Town Lake: biogeochemical & hydrologic processeseochemical & hydrologic processes 1Department of Geological Sciences, 871404, Arizona State University, Tempe, AZ 85287-1404 2 Department

  12. Some Fundamental Experiments on Apparent Dissolution Rate of Gas Phase in the Groundwater Recovery Processes of the Geological Disposal System - 12146

    SciTech Connect

    Yoshii, Taiki; Niibori, Yuichi; Mimura, Hitoshi [Dept. of Quantum Science and Energy Engineering, Graduate School of Engineering, Tohoku University, 6-6-01-2, Aramaki, Aza-Aoba, Aoba-ku, Sendai 980-8579 (Japan)

    2012-07-01

    The apparent dissolution rates of gas phase in the co-presence of solid phase were examined by in-room experiments in this study. The apparent dissolution rate of gas phase q (mol/m{sup 3}.s) was generally defined by q=aK{sub L}(?P{sub g}-c), where a (1/m) is specific surface area of the interface between gas and liquid phases, K{sub L} (m/s) is overall mass transfer coefficient, ? (mol/(Pa.m{sup 3})) is reciprocal number of Henry constant, P{sub g} (Pa) is partial pressure of gas phase, and c (mol/m{sup 3}) is the concentration of gas component in liquid phase. As a model gas, CO{sub 2} gas was used. For evaluating the values of K{sub L}, this study monitored pH or the migration rate of the interface between water/gas phases, using some experiments such as the packed beds and the micro channel consisting of granite chip and rubber sheet including a slit. In the results, the values of K{sub L} were distributed in the range from 5.0x10{sup -6} m/s to 5.0x10{sup -7} m/s. These values were small, in comparison with that (7.8x10{sup -4} m/s) obtained from the bubbling test where gas phase was continually injected into deionized water without solid phase. This means that the solid phase limits the local mixing of water phase near gas-liquid interfaces. (authors)

  13. Fundamentals of artificial intelligence

    Microsoft Academic Search

    W. Bibel; P. Jorrand

    1986-01-01

    This book covers the following topics: knowledge representation; features of knowledge; knowledge processing; deduction and computation; an introduction to automated deduction; fundamental mechanisms in machine learning and inductive inference; methods of automated reasoning; knowledge programming; term rewriting as a basis for the design of a functional and parallel programming language; a case study: the language FP2; and concurrent PROLOG: a

  14. Geologic Time

    NSDL National Science Digital Library

    William L. Newman

    1997-01-01

    The Earth is very old -- 4.5 billion years or more -- according to recent estimates. This vast span of time, called geologic time by earth scientists, is difficult to comprehend in the familiar time units of months and years, or even centuries. How then do scientists reckon geologic time, and why do they believe the Earth is so old? A great part of the secret of the Earth's age is locked up in its rocks, and our centuries-old search for the key led to the beginning and nourished the growth of geologic science.

  15. Geologic time

    USGS Publications Warehouse

    Newman, William L.

    2000-01-01

    The Earth is very old 4 1/2 billion years or more according to recent estimates. This vast span of time, called geologic time by earth scientists, is difficult to comprehend in the familiar time units of months and years, or even centuries. How then do scientists reckon geologic time, and why do they believe the Earth is so old? A great part of the secret of the Earth's age is locked up in its rocks, and our centuries-old search for the key led to the beginning and nourished the growth of geologic science.

  16. Geologic History

    NSDL National Science Digital Library

    Philip Medina

    This unit introduces younger students to the concept of relative versus absolute time and how geologists determine the age of geologic events and features. Topics include the laws that determine relative age (superposition, cross-cutting relationships, included fragments, and others), and how to re-construct the geologic history of an area using these relationships. There is also information on geologic correlation and the use of index fossils to determine relative age. The section on absolute time discusses some ways of measurement (tree rings, radioactive dating) and introduces the concepts of natural selection and mass extinctions. A vocabulary and downloadable, printable student worksheets are provided.

  17. Geology of a complex kimberlite pipe (K2 pipe, Venetia Mine, South Africa): insights into conduit processes during explosive ultrabasic eruptions

    NASA Astrophysics Data System (ADS)

    Brown, R. J.; Tait, M.; Field, M.; Sparks, R. S. J.

    2009-01-01

    K2 is a steep-sided kimberlite pipe with a complex internal geology. Geological mapping, logging of drillcore and petrographic studies indicate that it comprises layered breccias and pyroclastic rocks of various grain sizes, lithic contents and internal structures. The pipe comprises two geologically distinct parts: K2 West is a layered sequence of juvenile- and lithic-rich breccias, which dip 20-45° inwards, and K2 East consists of a steep-sided pipe-like body filled with massive volcaniclastic kimberlite nested within the K2 pipe. The layered sequence in K2 West is present to > 900 m below present surface and is interpreted as a sequence of pyroclastic rocks generated by explosive eruptions and mass-wasting breccias generated by rock fall and sector collapse of the pipe walls: both processes occurred in tandem during the infill of the pipe. Several breccia lobes extend across the pipe and are truncated by the steep contact with K2 East. Dense pyroclastic rocks within the layered sequence are interpreted as welded deposits. K2 East represents a conduit that was blasted through the layered breccia sequence at a late stage in the eruption. This phase may have involved fluidisation of trapped pyroclasts, with loss of fine particles and comminution of coarse clasts. We conclude that the K2 kimberlite pipe was emplaced in several distinct stages that consisted of an initial explosive enlargement, followed by alternating phases of accumulation and ejection.

  18. Schoolyard Geology

    NSDL National Science Digital Library

    This set of lessons provides teachers with ideas on how to turn their schoolyards into a rich geologic experience that students will find familiar, easily accessible, and personally relevant. The three lesson plans feature materials on mapping, rock descriptions and geologic interpretations, ages of rocks, and dinosaur tracks. Lesson 1, "Map Your Schoolyard," teaches students what maps are, what they are used for, and some symbols used on maps (north arrow, scale bar, legend, etc.). Lesson 2, "Rock Stories," illustrates how to make geologic observations and what important properties of rocks to look for. Lesson 3, "GeoSleuth Schoolyard," teaches students that geology is a lot like detective work, in which geologists infer the sequence and timing of events by collecting evidence and making observations. Relevant California state science standards are also listed.

  19. Water in a Crowd In many situations, form biology to geology, water occurs not as the pure bulk

    E-print Network

    Fayer, Michael D.

    Water in a Crowd In many situations, form biology to geology, water occurs not as the pure bulk species, and interacting with large organic molecules. In such situations, water does not behave in the same manner as it does in the pure bulk liquid. Water dynamics are fundamental to many processes

  20. Spatial distribution of seafloor bio-geological and geochemical processes as proxies of fluid flux regime and evolution of a carbonate/hydrates mound, northern Gulf of Mexico

    NASA Astrophysics Data System (ADS)

    Macelloni, Leonardo; Brunner, Charlotte A.; Caruso, Simona; Lutken, Carol B.; D'Emidio, Marco; Lapham, Laura L.

    2013-04-01

    Woolsey Mound, a carbonate/hydrate complex of cold seeps, vents, and seafloor pockmarks in Mississippi Canyon Block 118, is the site of the Gulf of Mexico Hydrates Research Consortium's (GOMHRC) multi-sensor, multi-disciplinary, permanent seafloor observatory. In preparation for installing the observatory, the site has been studied through geophysical, biological, geological, and geochemical surveys. By integrating high-resolution, swath bathymetry, acoustic imagery, seafloor video, and shallow geological samples in a morpho-bio-geological model, we have identified a complex mound structure consisting of three main crater complexes: southeast, northwest, and southwest. Each crater complex is associated with a distinct fault. The crater complexes exhibit differences in morphology, bathymetric relief, exposed hydrates, fluid venting, sediment accumulation rates, sediment diagenesis, and biological community patterns. Spatial distribution of these attributes suggests that the complexes represent three different fluid flux regimes: the southeast complex seems to be an extinct or quiescent vent; the northwest complex exhibits young, vigorous activity; and the southwest complex is a mature, fully open vent. Geochemical evidence from pore-water gradients corroborates this model suggesting that upward fluid flux waxes and wanes over time and that microbial activity is sensitive to such change. Sulfate and methane concentrations show that microbial activity is patchy in distribution and is typically higher within the northwest and southwest complexes, but is diminished significantly over the southeast complex. Biological community composition corroborates the presence of distinct conditions at the three crater complexes. The fact that three different fluid flux regimes coexist within a single mound complex confirms the dynamic nature of the plumbing system that discharges gases into bottom water. Furthermore, the spatial distribution of bio-geological processes appears to be a valid indicator of multiple fluid flux regimes that coexist at the mound.

  1. Healthcare fundamentals.

    PubMed

    Kauk, Justin; Hill, Austin D; Althausen, Peter L

    2014-07-01

    In order for a trauma surgeon to have an intelligent discussion with hospital administrators, healthcare plans, policymakers, or any other physicians, a basic understanding of the fundamentals of healthcare is paramount. It is truly shocking how many surgeons are unable to describe the difference between Medicare and Medicaid or describe how hospitals and physicians get paid. These topics may seem burdensome but they are vital to all business decision making in the healthcare field. The following chapter provides further insight about what we call "the basics" of providing medical care today. Most of the topics presented can be applied to all specialties of medicine. It is broken down into 5 sections. The first section is a brief overview of government programs, their influence on care delivery and reimbursement, and past and future legislation. Section 2 focuses on the compliance, care provision, and privacy statutes that regulate physicians who care for Medicare/Medicaid patient populations. With a better understanding of these obligations, section 3 discusses avenues by which physicians can stay informed of current and pending health policy and provides ways that they can become involved in shaping future legislation. The fourth section changes gears slightly by explaining how the concepts of trade restraint, libel, antitrust legislation, and indemnity relate to physician practice. The fifth, and final, section ties all of components together by describing how physician-hospital alignment can be mutually beneficial in providing patient care under current healthcare policy legislation. PMID:24918828

  2. United States Geological Survey Geospatial Information Response

    E-print Network

    Torgersen, Christian

    1 United States Geological Survey Geospatial Information Response is comprised of numerous components within the United States Geological Survey (USGS requirements and deactivation process in supporting natural hazards events. 1.2 Scope

  3. Terminology of geological time: Establishment of a community standard

    E-print Network

    Christie-Blick, Nicholas

    Terminology of geological time: Establishment of a community standard Marie-Pierre Aubry1 , John A recommended that geological time be described in a single set of terms and according to metric or SI ("SystĆØme that fundamental differences between date and duration, in the way that our profession expresses geological time

  4. Geology of Mojave National Preserve

    NSDL National Science Digital Library

    This website of the United States Geological Survey (USGS) and the National Park Service (NPS) highlights the geology of the Mojave National Preserve in California. It includes a field trip describing areas of interest at the preserve, as well as a geologic time scale describing the history and development of this area. Processes that shaped this region include volcanism, tectonics, faulting, erosion, deposition, spreading, intrusions, and glaciation. There is a geologic map of the area with units and a legend, and links to maps and technical papers.

  5. Cari L. Johnson $ Department of Geological and Environmental Sciences, Building 320, Stanford

    E-print Network

    Johnson, Cari

    ecological processes and events deep in geologic time. J. Michael Moldowan $ Department of Geolog- icalAUTHORS Cari L. Johnson $ Department of Geological and Environmental Sciences, Building 320, Stanford University, Stanford, California, 94305-2115; current address: Department of Geology

  6. Reports of planetary geology program, 1983

    NASA Technical Reports Server (NTRS)

    Holt, H. E. (compiler)

    1984-01-01

    Several areas of the Planetary Geology Program were addressed including outer solar system satellites, asteroids, comets, Venus, cratering processes and landform development, volcanic processes, aeolian processes, fluvial processes, periglacial and permafrost processes, geomorphology, remote sensing, tectonics and stratigraphy, and mapping.

  7. The preparation of illustrations for reports of the United States Geological survey : with brief descriptions of processes of reproduction

    USGS Publications Warehouse

    Ridgway, John L.

    1920-01-01

    There has been an obvious need in the Geological Survey o£ a paper devoted wholly to illustrations. No complete paper on the character, use, and mode of preparation of illustration has been published by the Survey, though brief suggestions concerning certain features of their use have been printed in connection wit other suggestions pertaining to publications. The present paper includes matter which it is hoped will be of service to authors in their work of making up original drafts of illustrations and to drafsmen who are using these originals in preparing more finished drawing but it is not a technical treatise on drafting.

  8. The influence of random slowdown process and lock-step effect on the fundamental diagram of the nonlinear pedestrian dynamics: An estimating-correction cellular automaton

    NASA Astrophysics Data System (ADS)

    Fu, Zhijian; Zhou, Xiaodong; Chen, Yanqiu; Gong, Junhui; Peng, Fei; Yan, Zidan; Zhang, Taolin; Yang, Lizhong

    2015-03-01

    Random slowdown process and lock-step effect, observed from real-life observation and the experiments of other researchers, were investigated in the view of the pedestrian microscopic behaviors. Due to the limited controllability, repeatability and randomness of the pedestrian experiments, a new estimating-correction cellular automaton was established to research the influence of random slowdown process and lock-step effect on the fundamental diagram. The first step of the model is to estimate the next time-step status of the neighbor cell in front of the tracked pedestrian. The second step is to correct the status and confirm the position of the tracked pedestrian in the next time-step. It is found that the random slowdown process and lock-step have significant influence on the curve configuration and the characteristic parameters, including the concavity-convexity, the inflection point, the maximum flow rate and the critical density etc. The random slowdown process reduces the utilization of the available space between two adjacent pedestrians in the longitudinal direction, especially in the region of intermediate density. However, the lock-step effect enhances the utilization of the available space, especially in the region of high density.

  9. Femtosecond dynamics of fundamental reaction processes in liquids: Proton transfer, geminate recombination, isomerization and vibrational relaxation. [Spiropyrans

    SciTech Connect

    Schwartz, B.J.

    1992-11-01

    The fast excited state intramolecular proton transfer of 3-hydroxyflavone is measured and effects of external hydrogen-bonding interactions on the proton transfer are studied. The proton transfer takes place in [approximately]240 fsec in nonpolar environments, but becomes faster than instrumental resolution of 110 fsec in methanol solution. The dynamics following photodissociation of CH[sub 2]I[sub 2] and other small molecules provide the first direct observations of geminate recombination. The recombination of many different photodissociating species occurs on a [approximately]350 fsec time scale. Results show that recombination yields but not rates depend on the solvent environment and suggest that recombination kinetics are dominated by a single collision with surrounding solvent cage. Studies of sterically locked phenyl-substituted butadienes offer new insights into the electronic structure and isomerization behavior of conjugated polyenes. Data show no simple correlation between hinderance of specific large amplitude motions and signatures of isomerizative behavior such as viscosity dependent excited state lifetimes, implying that the isomerization does not provide a suitable for simple condensed phase reaction rate theories. The spectral dynamics of a photochromic spiropyran indicate that recombination, isomerization and vibrational relaxation all play important roles in photoreactivity of complex molecules. The interplay of these microscopic phenomena and their effect on macroscopic properties such as photochromism are discussed. All the results indicate that the initial steps of the photochromic reaction process occur extremely rapidly. Laser system and computer codes for data analysis are discussed.

  10. Structural Geology

    NASA Astrophysics Data System (ADS)

    Weber, John; Frankel, Kurt L.

    2011-05-01

    Structural geology and continental tectonics were ushered in to the modern quantitative age of geosciences with the arrival of the global plate tectonics paradigm (circa 1968), derived using new data from the oceans' depths, and John Ramsay's 1967 seminal work, Folding and Fracturing of Rocks. Fossen is to be applauded for crafting a unique, high-caliber, and accessible undergraduate textbook on structural geology that faithfully reflects this advance and the subsequent evolution of the discipline. This well-written text draws on Fossen's wealth of professional experience, including his broad and diverse academic research and experience in the petroleum industry. This book is beautifully illustrated, with excellent original color diagrams and with impressive color field photographs that are all keyed to locations and placed into geologic context.

  11. Schizophrenia: the fundamental questions.

    PubMed

    Andreasen, N C

    2000-03-01

    Identifying the correct phentotype of schizophrenia is perhaps the most important goal of modern research in schizophrenia. This identification is the necessary antecedent of indentifying the pathophysiology and etiology. A working model is proposed, which suggests that the phenotype should be defined on the basis of abnormalities in neural circuits and a fundamental cognitive process. This type of unitary model may be more heuristic than early ones that were based on heterogeneous signs and symptoms. PMID:10719138

  12. Geologic Time

    NSDL National Science Digital Library

    Timothy Heaton

    This site contains 24 questions on the topic of geologic time, which covers dating techniques and unconformities. This is part of the Principles of Earth Science course at the University of South Dakota. Users submit their answers and are provided immediate feedback.

  13. Progress on the development of a three-dimensional capability for simulating large-scale complex geologic processes

    SciTech Connect

    Argueello, J.G.; Stone, C.M.; Fossum, A.F.

    1998-02-01

    Significant progress has been made in developing a three-dimensional capability for predicting the mechanical response of rock over spatial and time scales of geologic interest to the Oil and Gas industry. An Advanced Computational Technology Initiative (ACTI) initiated three years ago to achieve such a computational technology breakthrough has made significant progress towards its goal by adapting and improving the unique advanced quasistatic finite element technology developed by Sandia National Laboratories to the mechanics applications important to exploration and production (E and P). This capability now gives the industry a powerful tool to help reduce risk on prospects, improve pre-project initial reserve estimates, and lower operating costs. Progress to date on this program is reported herein by presenting and discussing the enhancements and adaptations that have been made to the technology, with specific examples to illustrate their use on large E and P geomechanics problems.

  14. The Geology of Callisto

    NASA Technical Reports Server (NTRS)

    Schenk, Paul M.

    1995-01-01

    The geology of Callisto is not boring. Although cratered terrain dominates Callisto (a key end-member of the Jovian satellite system), a number of more interesting features are apparent. Cratered terrain is broken into irregular map-able bright and dark subunits that vary in albedo by a factor of 2, and several relatively smooth units are depleted of small craters. Some of these areas may have been volcanically resurfaced. Lineaments, including parallel and radial sets, may be evidence for early global tectonism. Frost deposition occurs in cold traps, and impact scars have formed from tidally disrupted comets. Geologic evidence suggests that Callisto does have a chemically differentiated crust. Central pit and central dome craters and palimpsests are common. The preferred interpretation is that a relatively ice-rich material, at depths of 5 km or more, has been mobilized during impact and exposed as domes or palimpsests. The close similarity in crater morphologies and dimensions indicates that the outermost 10 km or so of Callisto may be as differentiated as on Ganymede. The geology of cratered terrain on Callisto is simpler than that of cratered terrain on Ganymede, however. Orbital evolution and tidal heating may provide the answer to the riddle of why Callisto and Ganymede are so different (Malhotra, 1991). We should expect a few surprises and begins to answer some fundamental questions when Callisto is observed by Galileo in late 1996.

  15. FUNDAMENTALS OF PLATE TECTONICS Fall Semester 2012-13

    E-print Network

    Polly, David

    FUNDAMENTALS OF PLATE TECTONICS Fall Semester 2012-13 Geological Sciences G454/G554 Section 32565, paleomagnetism, petrology, and structural geology that led to the development of plate tectonic theory student will prepare a paper on some aspect or applica- tion of plate tectonic theory. The paper should

  16. Teaching Geology

    NSDL National Science Digital Library

    The study of geology at the University of Colorado has a long and distinguished history, and in recent years they have also become increasingly interested in providing online teaching resources in the field. Educators will be glad to learn about this site's existence, as they can scroll through a list of interactive demonstrations that can be utilized in the classroom. Specifically, these demonstrations include a shaded interactive topographical map of the western United States, a magnetic field of the Earth, and several animated maps of various National Park sites. The site comes to a compelling conclusion with the inclusion of the geology department's slide library, which can be used without a password or registration.

  17. Geological assessing of urban environments with a systematic mapping survey: The 1:5000 urban geological map of Catalonia

    NASA Astrophysics Data System (ADS)

    Vilą, Miquel; Pi, Roser; Cirés, Jordi; de Paz, Ana; Berįstegui, Xavier

    2010-05-01

    The ground features of urban areas and the geologic processes that operate on them are, in general, strongly altered from their natural original condition as a result of anthropogenic activities. Assessing the stability of the ground, the flooding areas, and, the health risk as a consequence of soil pollution, are, among others, fundamental topics of urban areas that require a better understanding. The development of systematic urban geological mapping projects provides valuable resources to address these issues. Since 2007, the Institut Geologic de Catalunya (IGC) runs an urban geological mapping project, to provide accurate geologic information of county capitals and towns of more than 10000 inhabitants of Catalonia. The urban zones of 131 towns will be surveyed for this project, totalizing an area of about 2200 km2 to be mapped in 15 years. According to the 2008 census, the 82 % of the population of Catalonia (7.242.458 inhabitants) lives in the areas to be mapped in this project. The mapping project integrates in a GIS environment the following subjects: - Data from pre-existing geotechnical reports, historical geological and topographical maps and, from historical aerial photographs. - Data from available borehole databases. - Geological characterization of outcrops inside the urban network and neighbouring areas. - Geological, chemical and physical characterisation of representative rocks, sediments and soils. - Ortophotographs (0.5 m pixel size) and digital elevation models (5 meter grid size) made from historical aerial photographs, to depict land use changes, artificial deposits and geomorphological elements that are either hidden or destroyed by urban sprawl. - Detailed geological mapping of quaternary sediments, subsurface bedrock and artificial deposits. - Data from subsurface prospection in areas with insufficient or confuse data. - 3D modelling of the main geological surfaces such as the top of the pre-quaternary basement. All the gathered data is harmonised and stored it in a database. The analysis of the database allows to compile and print the 1:5000 scale urban geological map according to the 1:5000 topographic grid of Catalonia. The map is composed by a principal map, geologic cross sections and several complementary maps, charts and tables. Regardless of the geological map units, the principal map also includes the main artificial deposits (such as infilled river valleys and road embankments), very recent or current superficial deposits, contours of outcropping areas, structural data and other relevant information gathered in stations, sampling points, boreholes indicating the thickness of artificial deposits and the depth of the pre-quaternary basement, contour lines of the top of the pre-quaternary basement surface and, water level data. The complementary maps and charts may change depending on the gathered data, the geological features of the area and the urban typology. However, the most representative complementary maps that includes the printed urban map are the quaternary subsurface bedrock map and the isopach map of thickness of quaternary and anthropogenic deposits. The map also includes charts and tables of relevant physical and chemical parameters of the geological materials, harmonised downhole lithological columns from selected boreholes, and, photographs and figures illustrating the geology of the mapped area and how urbanisation has changed the natural environment. The object of this systematic urban mapping survey is to provide a robust database to be used in targeted studies related to urban planning, geoengineering works, soil pollution and other important environmental issues that society should deal in the future.

  18. Physical Geology

    NSDL National Science Digital Library

    Stephen Nelson

    This Tulane University course covers the nature of the Earth, the development of its surficial features, and the results of the interaction of chemical, physical, and biological factors on the planet. Lecture notes are about energy and minerals; igneous, metamorphic and sedimentary rocks; weathering and soils; geologic time; mass wasting; streams; groundwater; wind action and deserts; oceans; deformation of rock; earthquakes and the interior of the Earth; global tectonics; planetary changes; and glaciers.

  19. Influence of introgression and geological processes on phylogenetic relationships of Western North American mountain suckers (Pantosteus, Catostomidae).

    PubMed

    Unmack, Peter J; Dowling, Thomas E; Laitinen, Nina J; Secor, Carol L; Mayden, Richard L; Shiozawa, Dennis K; Smith, Gerald R

    2014-01-01

    Intense geological activity caused major topographic changes in Western North America over the past 15 million years. Major rivers here are composites of different ancient rivers, resulting in isolation and mixing episodes between river basins over time. This history influenced the diversification of most of the aquatic fauna. The genus Pantosteus is one of several clades centered in this tectonically active region. The eight recognized Pantosteus species are widespread and common across southwestern Canada, western USA and into northern Mexico. They are typically found in medium gradient, middle-elevation reaches of rivers over rocky substrates. This study (1) compares molecular data with morphological and paleontological data for proposed species of Pantosteus, (2) tests hypotheses of their monophyly, (3) uses these data for phylogenetic inferences of sister-group relationships, and (4) estimates timing of divergence events of identified lineages. Using 8055 base pairs from mitochondrial DNA protein coding genes, Pantosteus and Catostomus are reciprocally monophyletic, in contrast with morphological data. The only exception to a monophyletic Pantosteus is P. columbianus whose mtDNA is closely aligned with C. tahoensis because of introgression. Within Pantosteus, several species have deep genetic divergences among allopatric sister lineages, several of which are diagnosed and elevated to species, bringing the total diversity in the group to 11 species. Conflicting molecular and morphological data may be resolved when patterns of divergence are shown to be correlated with sympatry and evidence of introgression. PMID:24619087

  20. Influence of Introgression and Geological Processes on Phylogenetic Relationships of Western North American Mountain Suckers (Pantosteus, Catostomidae)

    PubMed Central

    Unmack, Peter J.; Dowling, Thomas E.; Laitinen, Nina J.; Secor, Carol L.; Mayden, Richard L.; Shiozawa, Dennis K.; Smith, Gerald R.

    2014-01-01

    Intense geological activity caused major topographic changes in Western North America over the past 15 million years. Major rivers here are composites of different ancient rivers, resulting in isolation and mixing episodes between river basins over time. This history influenced the diversification of most of the aquatic fauna. The genus Pantosteus is one of several clades centered in this tectonically active region. The eight recognized Pantosteus species are widespread and common across southwestern Canada, western USA and into northern Mexico. They are typically found in medium gradient, middle-elevation reaches of rivers over rocky substrates. This study (1) compares molecular data with morphological and paleontological data for proposed species of Pantosteus, (2) tests hypotheses of their monophyly, (3) uses these data for phylogenetic inferences of sister-group relationships, and (4) estimates timing of divergence events of identified lineages. Using 8055 base pairs from mitochondrial DNA protein coding genes, Pantosteus and Catostomus are reciprocally monophyletic, in contrast with morphological data. The only exception to a monophyletic Pantosteus is P. columbianus whose mtDNA is closely aligned with C. tahoensis because of introgression. Within Pantosteus, several species have deep genetic divergences among allopatric sister lineages, several of which are diagnosed and elevated to species, bringing the total diversity in the group to 11 species. Conflicting molecular and morphological data may be resolved when patterns of divergence are shown to be correlated with sympatry and evidence of introgression. PMID:24619087

  1. Chip-off-the-old-rock: the study of reservoir-relevant geological processes with real-rock micromodels.

    PubMed

    Song, Wen; de Haas, Thomas W; Fadaei, Hossein; Sinton, David

    2014-11-21

    We present a real-rock micromodel approach whereby microfluidic channels are fabricated in a naturally occurring mineral substrate. The method is applied to quantify calcite dissolution which is relevant to oil/gas recovery, CO2 sequestration, and wastewater disposal in carbonate formations - ubiquitous worldwide. The key advantage of this method is the inclusion of both the relevant substrate chemistry (not possible with conventional microfluidics) and real-time pore-scale resolution (not possible with core samples). Here, microchannels are etched into a natural calcite crystal and sealed with a glass slide. The approach is applied to study acidified brine flow through a single channel and a two-dimensional micromodel. The single-channel case conforms roughly to a 1-D analytical description, with crystal orientation influencing the local dissolution rate an additional 25%. The two-dimensional experiments show highly flow-directed dissolution and associated positive feedback wherein acid preferentially invades high conductivity flow paths, resulting in higher dissolution rates ('wormholing'). These experiments demonstrate and validate the approach of microfabricating fluid structures within natural minerals for transport and geochemical studies. More broadly, real-rock microfluidics open the door to a vast array of lab-on-a-chip opportunities in geology, reservoir engineering, and earth sciences. PMID:25236399

  2. A Comparison of Multivariate and Pre-Processing Methods for Quantitative Laser-Induced Breakdown Spectroscopy of Geologic Samples

    NASA Technical Reports Server (NTRS)

    Anderson, R. B.; Morris, R. V.; Clegg, S. M.; Bell, J. F., III; Humphries, S. D.; Wiens, R. C.

    2011-01-01

    The ChemCam instrument selected for the Curiosity rover is capable of remote laser-induced breakdown spectroscopy (LIBS).[1] We used a remote LIBS instrument similar to ChemCam to analyze 197 geologic slab samples and 32 pressed-powder geostandards. The slab samples are well-characterized and have been used to validate the calibration of previous instruments on Mars missions, including CRISM [2], OMEGA [3], the MER Pancam [4], Mini-TES [5], and Moessbauer [6] instruments and the Phoenix SSI [7]. The resulting dataset was used to compare multivariate methods for quantitative LIBS and to determine the effect of grain size on calculations. Three multivariate methods - partial least squares (PLS), multilayer perceptron artificial neural networks (MLP ANNs) and cascade correlation (CC) ANNs - were used to generate models and extract the quantitative composition of unknown samples. PLS can be used to predict one element (PLS1) or multiple elements (PLS2) at a time, as can the neural network methods. Although MLP and CC ANNs were successful in some cases, PLS generally produced the most accurate and precise results.

  3. MER Field Geologic Traverse in Gusev Crater, Mars: Initial Results From the Perspective of Spirit

    NASA Technical Reports Server (NTRS)

    Crumpler, L.; Cabrol, N.; desMarais, D.; Farmer, J.; Golmbek, M.; Grant, J.; Greely, R.; Grotzinger, J.; Haskin, L.; Arvidson, R.

    2004-01-01

    This report casts the initial results of the traverse and science investigations by the Mars Exploration Rover (MER) Spirit at Gusev crater [1] in terms of data sets commonly used in field geologic investigations: Local mapping of geologic features, analyses of selected samples, and their location within the local map, and the regional context of the field traverse in terms of the larger geologic and physiographic region. These elements of the field method are represented in the MER characterization of the Gusev traverse by perspective-based geologic/morphologic maps, the placement of the results from Mossbauer, APXS, Microscopic Imager, Mini-TES and Pancam multispectral studies in context within this geologic/ morphologic map, and the placement of the overall traverse in the context of narrow-angle MOC (Mars Orbiter Camera) and descent images. A major campaign over a significance fraction of the mission will be the first robotic traverse of the ejecta from a Martian impact crater along an approximate radial from the crater center. The Mars Exploration Rovers have been conceptually described as 'robotic field geologists', that is, a suite of instruments with mobility that enables far-field traverses to multiple sites located within a regional map/image base at which in situ analyses may be done. Initial results from MER, where the field geologic method has been used throughout the initial course of the investigation, confirm that this field geologic model is applicable for remote planetary surface exploration. The field geologic method makes use of near-field geologic characteristics ('outcrops') to develop an understanding of the larger geologic context through continuous loop of rational steps focused on real-time hypothesis identification and testing. This poster equates 'outcrops' with the locations of in situ investigations and 'regional context' with the geology over distance of several kilometers. Using this fundamental field geologic method, we have identified the basic local geologic materials on the floor of Gusev at this site, their compositions and likely lithologies, origins, processes that have modified these materials, and their potential significance in the interpretation of the regional geology both spatially and temporally.

  4. Model Fundamentals - version 2

    NSDL National Science Digital Library

    2014-09-14

    Model Fundamentals, part of the Numerical Weather Prediction Professional Development Series and the "NWP Training Series: Effective Use of NWP in the Forecast Process", describes the components of an NWP model and how they fit into the forecast development process. It also explores why parameterization of many physical processes is necessary in NWP models. The module covers background concepts and terminology necessary for learning from the other modules in this series on NWP. Back in 2000, the subject matter expert for this module was Dr. Ralph Petersen of the National Centers for Environmental Prediction, Environmental Modeling Center (NCEP/EMC). Revisions to the module were made in 2009 by Drs. Bill Bua and Stephen Jascourt, from the NWP team at UCAR/COMET.

  5. Results from an International Simulation Study on Coupled Thermal,Hydrological, and Mechanical (THM) Processes near Geological NuclearWaste Repositories

    SciTech Connect

    Rutqvist, Jonny; Rutqvist, J.; Barr, D.; Birkholzer, J.T.; Chijimatsu, M.; Kolditz, O.; Liu, Q.-S; Oda, Y.; Wang, W.; Zhang, C.-Y.

    2007-10-23

    As part of the ongoing international DECOVALEX project, four research teams used five different models to simulate coupled thermal, hydrological, and mechanical (THM) processes near waste emplacement drifts of geological nuclear waste repositories. The simulations were conducted for two generic repository types, one with open and the other with back-filled repository drifts, under higher and lower postclosure temperatures, respectively. In the completed first model inception phase of the project, a good agreement was achieved between the research teams in calculating THM responses for both repository types, although some disagreement in hydrological responses is currently being resolved. In particular, good agreement in the basic thermal-mechanical responses was achieved for both repository types, even though some teams used relatively simplified thermal-elastic heat-conduction models that neglected complex near-field thermal-hydrological processes. The good agreement between the complex and simplified process models indicates that the basic thermal-mechanical responses can be predicted with a relatively high confidence level.

  6. Geologic Time

    NSDL National Science Digital Library

    This Classroom Connectors lesson plan discusses the characteristics of geologic time, including the law of superposition, fossil preservation, casts and molds, and various events through the history of the Earth. The site provides goals, objectives, an outline, time required, materials, activities, and closure ideas for the lesson. The Classroom Connectors address content with an activity approach while incorporating themes necessary to raise the activity to a higher cognition level. The major motivation is to employ instructional strategies that bring the students physically and mentally into touch with the science they are studying.

  7. Geological Mapping of Impact Melt Deposits at Lunar Complex Craters: New Insights into Morphological Diversity, Distribution and the Cratering Process

    NASA Astrophysics Data System (ADS)

    Dhingra, D.; Head, J. W., III; Pieters, C. M.

    2014-12-01

    We have completed high resolution geological mapping of impact melt deposits at the young lunar complex craters (<1 billion years) Copernicus, Jackson and Tycho using data from recent missions. Crater floors being the largest repository of impact melt, we have mapped their morphological diversity expressed in terms of varied surface texture, albedo, character and occurrence of boulder units as well as relative differences in floor elevation. Examples of wall and rim impact melt units and their relation to floor units have also been mapped. Among the distinctive features of these impact melt deposits are: 1) Impact Melt Wave Fronts: These are extensive (sometimes several kilometers in length) and we have documented their occurrence and distribution in different parts of the crater floor at Jackson and Tycho. These features emphasize melt mobility and style of emplacement during the modification stage of the craters. 2) Variations in Floor Elevations: Spatially extensive and coherent sections of crater floors have different elevations at all the three craters. The observed elevation differences could be caused by subsidence due to cooling of melt and/or structural failure, together with a contribution from regional slope. 3) Melt-Covered Megablocks: We also observe large blocks/rock-fragments (megablocks) covered in impact melt, which could be sections of collapsed wall or in some cases, subdued sections of central peaks. 4) Melt-Covered Central Peaks: Impact melt has also been mapped on the central peaks but varies in spatial extent among the craters. The presence of melt on peaks must be taken into account when interpreting peak mineralogy as exposures of deeper crust. 5) Boulder Distribution: Interesting trends are observed in the distribution of boulder units of various sizes; some impact melt units have spatially extensive boulders, while boulder distribution is very scarce in other units on the floor. We interpret these distributions to be influenced by a) the differential collapse of the crater walls during the modification stage, and b) the amount of relative melt volume retained in different parts of the crater floor. These observations provide important documentation of the morphological diversity and better understanding of the emplacement and final distribution of impact melt deposits.

  8. Marine Geology: Research Beneath the Sea

    NSDL National Science Digital Library

    Another informative offering from the US Geological Survey is the Marine Geology: Research Beneath the Sea Web site. Visitors can read about the agency's Marine Geology program which "strives to increase our understanding of the geology of the lands covered by water." Topics include methods and equipment used for the research, plate tectonics, resources in the marine realm, predicting effects of marine processes, new frontiers, and even images of marine geology. This interesting and unique site does a good job of explaining and educating the public on this important segment of the agency's research.

  9. Precise determination of ?88Sr in rocks, minerals, and waters by double-spike TIMS: A powerful tool in the study of chemical, geologic, hydrologic and biologic processes

    USGS Publications Warehouse

    Neymark, Leonid A.; Premo, Wayne R.; Mel'nikov, Nikolay N.; Emsbo, Poul

    2014-01-01

    We present strontium isotopic (88Sr/86Sr and 87Sr/86Sr) results obtained by 87Sr–84Sr double spike thermal ionization mass-spectrometry (DS-TIMS) for several standards as well as natural water samples and mineral samples of abiogenic and biogenic origin. The detailed data reduction algorithm and a user-friendly Sr-specific stand-alone computer program used for the spike calibration and the data reduction are also presented. Accuracy and precision of our ?88Sr measurements, calculated as permil (‰) deviations from the NIST SRM-987 standard, were evaluated by analyzing the NASS-6 seawater standard, which yielded ?88Sr = 0.378 ± 0.009‰. The first DS-TIMS data for the NIST SRM-607 potassium feldspar standard and for several US Geological Survey carbonate, phosphate, and silicate standards (EN-1, MAPS-4, MAPS-5, G-3, BCR-2, and BHVO-2) are also reported. Data obtained during this work for Sr-bearing solids and natural waters show a range of ?88Sr values of about 2.4‰, the widest observed so far in terrestrial materials. This range is easily resolvable analytically because the demonstrated external error (±SD, standard deviation) for measured ?88Sr values is typically ?0.02‰. It is shown that the “true” 87Sr/86Sr value obtained by the DS-TIMS or any other external normalization method combines radiogenic and mass-dependent mass-fractionation effects, which cannot be separated. Therefore, the “true” 87Sr/86Sr and the ?87Sr parameter derived from it are not useful isotope tracers. Data presented in this paper for a wide range of naturally occurring sample types demonstrate the potential of the ?88Sr isotope tracer in combination with the traditional radiogenic 87Sr/86Sr tracer for studying a variety of biological, hydrological, and geological processes.

  10. An evaluation of the ERTS data collection system as a potential operational tool. [automatic hydrologic data collection and processing system for geological surveys

    NASA Technical Reports Server (NTRS)

    Paulson, R. W.

    1974-01-01

    The Earth Resources Technology Satellite Data Collection System has been shown to be, from the users vantage point, a reliable and simple system for collecting data from U.S. Geological Survey operational field instrumentation. It is technically feasible to expand the ERTS system into an operational polar-orbiting data collection system to gather data from the Geological Survey's Hydrologic Data Network. This could permit more efficient internal management of the Network, and could enable the Geological Survey to make data available to cooperating agencies in near-real time. The Geological Survey is conducting an analysis of the costs and benefits of satellite data-relay systems.

  11. Illinois State Geological Survey

    NSDL National Science Digital Library

    The Illinois State Geological Survey (ISGS) homepage provides information on geologic mapping, earthquakes, fossils, groundwater, wetlands, glacial geology, bedrock geology, and Lake Michigan geology. Educational materials include field trip guides, short publications on Illinois geology for students and teachers, online tours, single-page maps, and a geologic column. Other materials include databases and collections of GIS data, well records, drill cores, and mining information; a bibliography of Illinois geology; online maps and data; and information on water and land use, resource development, and geologic hazards.

  12. Fundamental aspects of quantum theory

    Microsoft Academic Search

    V. Gorini; A. Frigerio

    1986-01-01

    This book presents information on the following topics: general problems and crucial experiments; the classical behavior of measuring instruments; quantum interference effect for two atoms radiating a single photon; quantization and stochastic processes; quantum Markov processes driven by Bose noise; chaotic behavior in quantum mechanics; quantum ergodicity and chaos; microscopic and macroscopic levels of description; fundamental properties of the ground

  13. Chemical Engineering Division fuel cycle programs. Quarterly progress report, April-June 1979. [Pyrochemical/dry processing; waste encapsulation in metal; transport in geologic media

    SciTech Connect

    Steindler, M.J.; Ader, M.; Barletta, R.E.

    1980-09-01

    For pyrochemical and dry processing materials development included exposure to molten metal and salt of Mo-0.5% Ti-0.07% Ti-0.01% C, Mo-30% W, SiC, Si/sub 2/ON/sub 2/, ZrB/sub 2/-SiC, MgAl/sub 2/O/sub 4/, Al/sub 2/O/sub 3/, AlN, HfB/sub 2/, Y/sub 2/O/sub 3/, BeO, Si/sub 3/N/sub 4/, nickel nitrate-infiltrated W, W-coated Mo, and W-metallized alumina-yttria. Work on Th-U salt transport processing included solubility of Th in liquid Cd, defining the Cd-Th and Cd-Mg-Th phase diagrams, ThO/sub 2/ reduction experiments, and electrolysis of CaO in molten salt. Work on pyrochemical processes and associated hardware for coprocessing U and Pu in spent FBR fuels included a second-generation computer model of the transport process, turntable transport process design, work on the U-Cu-Mg system, and U and Pu distribution coefficients between molten salt and metal. Refractory metal vessels are being service-life tested. The chloride volatility processing of Th-based fuel was evaluated for its proliferation resistance, and a preliminary ternary phase diagram for the Zn-U-Pu system was computed. Material characterization and process analysis were conducted on the Exportable Pyrochemical process (Pyro-Civex process). Literature data on oxidation of fissile metals to oxides were reviewed. Work was done on chemical bases for the reprocessing of actinide oxides in molten salts. Flowsheets are being developed for the processing of fuel in molten tin. Work on encapsulation of solidified radioactive waste in metal matrix included studies of leach rate of crystalline waste materials and of the impact resistance of metal-matrix waste forms. In work on the transport properties of nuclear waste in geologic media, adsorption of Sr on oolitic limestone was studied, as well as the migration of Cs in basalt. Fitting of data on the adsorption of iodate by hematite to a mathematical model was attempted.

  14. Modelling of Geological Structures Using Emergence

    NASA Astrophysics Data System (ADS)

    Hillier, M.; de Kemp, E. A.; Sprague, K.

    2009-05-01

    A complex system based approach is used to model geological structures. Preliminary work is presented to show how mutually interacting agents can be used to probe local regions and obtain emergent behaviour of its geometrical properties. Models are built bottom up from the smaller components to simulate regions from camp scales to regional scales. In nature, very complex structures exhibiting discontinuous and heterogeneous features are common. Modelling such regions using conventional methods is cumbersome and influences between close proximity zones are generally not considered. Agents are able to detect local and global features in the entire model space, as detailed as the data set allows. These features are incorporated into the interpolation of a modeled zone if those features are coupled to that location. We attempt to see if opportunities exist for exploiting complex systems approaches in what is a classical knowledge driven modelling domain with high emphasis on expert interpretive methods. Geological maps (2D, 3D or 4D) are fundamentally an emergent result of an iterative mental process which focuses on reconciling disparate data. The end goal of our research is to point a way forward in which complexity can support the simulation of maps and thus support the interpretive workflow.

  15. Total volume and latitudinal variations of the sedimentary trench-fill off Central and Southern Chile: A record of short and long-term geologic processes

    NASA Astrophysics Data System (ADS)

    Geersen, J.; Voelker, D.; Contreras Reyes, E.

    2012-12-01

    The amount and composition of trench sediment that is underthrust in a subduction zone impacts on the physical state of the shallow megathrust. Knowledge about the sedimentary and tectonic state and the geologic history of a trench system is therefore an important step towards understanding the structural and seismotectonic evolution of a convergent margin. The Chilean Trench south of 32°S is a sediment-filled basin that stretches in N-S direction. Variations in trench-fill are directly linked to and controlled by a number of sedimentary-tectonic processes and their interplay over space and time. In this work we unravel the individual processes for a ~1500 km long segment of the Chilean trench (32°S-46°S) and investigate their temporal and spatial significance. We use swath bathymetric and reflection seismic data to produce grids of the seafloor and the surface of the subducting oceanic plate buried beneath the trench sediments. The volume of the sedimentary trench-fill and its along-strike variations are derived from the difference between the two grids. Our results indicate that the volumetric sediment distribution can be best explained by high sediment input in the south and active northward sediment transport along the trench during glacial periods. However, during interglacial periods, small-scale factors that locally modify the sediment input seem to dominate. For the future along-strike variations in sediment volume will be compared with variations in structure and seismic behavior of the margin.

  16. Geological Time Scale

    NSDL National Science Digital Library

    This document describes how geologic time is approached in discussions of geologic topics. The uses of relative time and absolute time are compared, and a geologic time scale is provided to represent both concepts. References are provided.

  17. Geologic Technician New Curriculum

    ERIC Educational Resources Information Center

    Karp, Stanley E.

    1970-01-01

    Describes a developing two-year geologic technician program at Bakersfield College in which a student may major in five areas - geologic drafting, land and legal, geologic assistant, engineering or paleontology. (RR)

  18. Vesta: A Geological Overview

    NASA Astrophysics Data System (ADS)

    Jaumann, R.

    2012-04-01

    Observations from the Dawn spacecraft [1] enable the derivation of the asteroid 4Vesta's shape, facilitate mapping of the surface geology, and provide the first evidence for interpreting Vesta's geological evolution. Science data were acquired during the approach to Vesta, a circular polar (Survey) orbit at an altitude of 2700 km providing ~ 230 m/pix camera scale, and during a circular high-altitude mapping orbit (HAMO) at 700 km altitude with a camera scale of ~ 65 m/pixel. Currently Dawn is orbiting Vesta in a low-altitude mapping orbit (LAMO) at 210 km altitude, yielding a global image coverage of ~20 m/pixel at the time of EGU [2,3,4,5]. Geomorphology and distribution of surface features provide evidence for impact cratering, tectonic activity, and regolith and probable volcanic processes. Craters with dark rays, bright rays, and dark rim streaks have been observed, suggesting buried stratigraphy. The largest fresh craters retain a simple bowl-shaped morphology, with depth/diameter ratios roughly comparable to lunar values. The largest crater Rheasilvia, an ~500 km diameter depression at the south pole, includes an incomplete inward facing cuspate scarp and a large central mound surrounded by unusual complex arcuate ridge and groove patterns, and overlies an older ~400 km wide basin. A set of large equatorial troughs is related to these south polar structures. Vesta exhibits rugged topography ranging from -22 km to +19 km relative to a best fit ellipsoidal shape. Vesta's topography has a much greater range in elevation relative to its radius (15%) than do the Moon and Mars (1%) or the Earth (0.3%), but less than highly battered smaller asteroids like Lutetia (40%). This also identifies Vesta as a transitional body between asteroids and planets. The surface of Vesta exhibits very steep topographic slopes that are near the angle of repose. Impacts onto these steep surfaces, followed by slope failure, make resurfacing - due to impacts and their associated gravitational forces and seismic activity - an important geologic process on Vesta that significantly alters the morphology of geologic features and adds to the complexity of its geologic history. In general, Vesta's geology is more like the Moon and rocky planets than other asteroids.

  19. Geology of the Caribbean

    USGS Publications Warehouse

    Dillon, William P.; Edgar, N.T.; Scanlon, K.M.; Klitgord, Kim D.

    1987-01-01

    The Venezuelan and Colombian basins are located on the Caribbean Plate whilst the Yucatan basin is on the North American Plate. The processes occurring at the boundaries between the Caribbean Plate and the adjacent North American, South American and Cocos Plates, and the resulting surface features and patterns of volcanic and earthquake activity are described. Most of the Caribbean area is floored by atypical oceanic crust and its most valuable main geologic resources identified so far are petroleum, together with sand and gravel. Geological research is being carried out with techniques for broad-range swath imaging of the seafloor, such as GLORIA, and for directly measuring the movement between plates. -J.G.Harvey

  20. Geology of Wisconsin

    NSDL National Science Digital Library

    Steven Dutch

    1997-09-10

    This site contains geologic maps of Wisconsin including relief and topography maps; maps of the bedrock geology and elevation, Pleistocene geology, thickness of unconsolidated deposits, and soils; and atlases of geologic history. There is information on: rock types, Paleozoic formations, and the Pleistocene and Precambrian history of Wisconsin; how to obtain a geologic map of personal property; the Niagara Escarpment; castellated mounds; geologic field localities; and unusual weather events in Wisconsin. There is also a data table on earthquakes in Wisconsin.

  1. Geologic Mapping on Mars

    NSDL National Science Digital Library

    Germari De Villiers

    This lab is part of a Lunar and Planetary Geology course offered to both geology and non-geology majors, and it involves basic geological mapping of an area within the Tyrrhena Patera region on Mars. Students are encouraged to work in groups to prepare a geological map from a photomosaic map and to interpret the geologic stratigraphy from a geological map of the greater area. This activity reinforces mapping skills as well as group work skills, and aims to teach students more about Martian stratigraphy and geology through a hands-on activity.

  2. Physical Characteristics, Geologic Setting, and Possible Formation Processes of Spring Deposits on Mars Based on Terrestrial Analogs

    NASA Technical Reports Server (NTRS)

    Crumpler, L. S.

    2003-01-01

    Spring formation is a predicted consequence of the interaction of former Martian aquifers with structures common to Mars, including basin margins, Tharsis structures, and other structural deformation characteristics. The arid environment and high abundance of water soluble compounds in the crust will have likewise encouraged spring deposit formation at spring sites. Such spring deposits may be recognized from morphological criteria if the characteristics of formation and preservation are understood. An important first step in the current Mars exploration strategy [10] is the detection of sites where there is evidence for past or present near-surface water on Mars. This study evaluates the large-scale morphology of spring deposits and the physical processes of their formation, growth, and evolution in terms that relate to (1) their identification in image data, (2) their formation, evolution, and preservation in the environment of Mars, and (3) their potential as sites of long-term or late stage shallow groundwater emergence at the surface of Mars.

  3. MODFLOW-2000, the U.S. Geological Survey Modular Ground-Water Model--Documentation of the SEAWAT-2000 Version with the Variable-Density Flow Process (VDF) and the Integrated MT3DMS Transport Process (IMT)

    USGS Publications Warehouse

    Langevin, Christian D.; Shoemaker, W. Barclay; Guo, Weixing

    2003-01-01

    SEAWAT-2000 is the latest release of the SEAWAT computer program for simulation of three-dimensional, variable-density, transient ground-water flow in porous media. SEAWAT-2000 was designed by combining a modified version of MODFLOW-2000 and MT3DMS into a single computer program. The code was developed using the MODFLOW-2000 concept of a process, which is defined as ?part of the code that solves a fundamental equation by a specified numerical method.? SEAWAT-2000 contains all of the processes distributed with MODFLOW-2000 and also includes the Variable-Density Flow Process (as an alternative to the constant-density Ground-Water Flow Process) and the Integrated MT3DMS Transport Process. Processes may be active or inactive, depending on simulation objectives; however, not all processes are compatible. For example, the Sensitivity and Parameter Estimation Processes are not compatible with the Variable-Density Flow and Integrated MT3DMS Transport Processes. The SEAWAT-2000 computer code was tested with the common variable-density benchmark problems and also with problems representing evaporation from a salt lake and rotation of immiscible fluids.

  4. Fundamentals of Space Systems

    NASA Astrophysics Data System (ADS)

    Pisacane, Vincent L.

    2005-06-01

    Fundamentals of Space Systems was developed to satisfy two objectives: the first is to provide a text suitable for use in an advanced undergraduate or beginning graduate course in both space systems engineering and space system design. The second is to be a primer and reference book for space professionals wishing to broaden their capabilities to develop, manage the development, or operate space systems. The authors of the individual chapters are practicing engineers that have had extensive experience in developing sophisticated experimental and operational spacecraft systems in addition to having experience teaching the subject material. The text presents the fundamentals of all the subsystems of a spacecraft missions and includes illustrative examples drawn from actual experience to enhance the learning experience. It included a chapter on each of the relevant major disciplines and subsystems including space systems engineering, space environment, astrodynamics, propulsion and flight mechanics, attitude determination and control, power systems, thermal control, configuration management and structures, communications, command and telemetry, data processing, embedded flight software, survuvability and reliability, integration and test, mission operations, and the initial conceptual design of a typical small spacecraft mission.

  5. Old Geology and New Geology

    NASA Technical Reports Server (NTRS)

    2003-01-01

    [figure removed for brevity, see original site]

    Released 28 May 2003

    Mangala Vallis one of the large outflow channels that channeled large quantities of water into the northern lowlands, long ago on geological timescales. This valley is one of the few in the southern hemisphere, as well as one of the few west of the Tharsis bulge. A closer look at the channel shows more recent weathering of the old water channel: the walls of the channel show small, dark slope streaks that form in dusty areas; and much of the surrounding terrain has subtle linear markings trending from the upper left to the lower right, which are probably features sculpted and streamlined by the wind. Geology still shapes the surface of Mars today, but its methods over the eons have changed.

    Image information: VIS instrument. Latitude -6, Longitude 209.6 East (150.4 West). 19 meter/pixel resolution.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  6. Identifying and quantifying natural CO2 sequestration processes over geological timescales: The Jackson Dome CO2 Deposit, USA

    NASA Astrophysics Data System (ADS)

    Zhou, Zheng; Ballentine, Chris J.; Schoell, Martin; Stevens, Scott H.

    2012-06-01

    CO2 sources, sinks and migration mechanisms in natural CO2 gas fields provide critical analogues for developing the safe application of anthropogenic CO2 sequestration technologies. Here we use noble gas and carbon isotopes, together with other gases, to identify and quantify the origin, transport and trapping mechanisms of CO2 in the Late Cretaceous Jackson Dome CO2 gas deposit (98.75% to 99.38% CO2). Located in central Mississippi, USA, and producing from >5000 m, it is one of the deepest commercial CO2 gas fields in the world. 10 gas samples from producing wells were determined for their noble gas, chemical and stable carbon isotope composition. 3He/4He ratios range between 4.27Ra and 5.01Ra (where Ra is the atmospheric value of 1.4 × 10-6), indicating a strong mantle signature. Similar to CO2 deposits worldwide, CO2/3He decreases with increasing groundwater-derived 20Ne (and 4He). We model several different processes that could account for the Jackson Dome data, and conclude that, similar to other CO2 dominated deposits, a Groundwater Gas Stripping and Re-dissolution (GGS-R) process best accounts for observed 20Ne/36Ar, 84Kr/36Ar, CO2/3He, ?13C(CO2), 4He, 20Ne and 36Ar. In this context, crustal and magmatic CO2 components contribute 57% and 43%, respectively. Changes in CO2/3He across the field show that groundwater contact is responsible for up to 75% loss of original emplaced CO2. ?13C(CO2) variance limits the degree of precipitation to be less than 27%, with the remaining CO2 loss being accounted for by dissolution only. A higher degree of dissolution gas loss and evidence for water contact at the reservoir crest compared to the reservoir flanks is used to argue that CO2 in this system has not undergone subsequent loss to either dissolution or precipitation since shortly after reservoir filling at over 60 Ma.

  7. Colorado Geological Survey

    NSDL National Science Digital Library

    The Colorado Geological Survey (CGS) is an agency of state government within the Department of Natural Resources whose mission is to help reduce the impact of geologic hazards on the citizens of Colorado, to promote the responsible economic development of mineral and mineral fuel resources, to provide geologic insight into water resources, and to provide geologic advice and information to a variety of constituencies. This site contains extensive information about Colorado geology such as maps, a geologic time scale for the state, program information, and state field trip information. This site hosts the Avalanche Information Center which contains avalanche forecasting and education center details. Publications report on geologic hazards, land use, environmental geology, mineral resources, oil, gas, coal, geologic mapping and earthquake information for the state. There are online editions of RockTalk, which is a quarterly newsletter published by the Colorado Geological Survey dealing with all aspects of geology throughout the state of Colorado. Links are provided for more resources.

  8. PROCEEDINGS: JOINT SYMPOSIUM ON DRY SO2 AND SIMULTANEOUS SO2/NOX CONTROL TECHNOLOGIES (1ST). VOLUME 1. FUNDAMENTAL RESEARCH AND PROCESS DEVELOPMENT

    EPA Science Inventory

    Forty six papers describing recent advances in dry sorbent injection technologies for SO2 control were presented at the 1st Joint Symposium on Dry SO2 and Simultaneous SO2/NOx Control Technologies. These papers covered the following topics: fundamental research; pilot-scale devel...

  9. Exchange Rates and Fundamentals.

    ERIC Educational Resources Information Center

    Engel, Charles; West, Kenneth D.

    2005-01-01

    We show analytically that in a rational expectations present-value model, an asset price manifests near-random walk behavior if fundamentals are I (1) and the factor for discounting future fundamentals is near one. We argue that this result helps explain the well-known puzzle that fundamental variables such as relative money supplies, outputs,…

  10. Pristine Noachian crust and key geologic transitions in the lower walls of Valles Marineris: Insights into early igneous processes on Mars

    NASA Astrophysics Data System (ADS)

    Flahaut, Jessica; Quantin, Cathy; Clenet, Harold; Allemand, Pascal; Mustard, John F.; Thomas, Pierre

    2012-09-01

    Valles Marineris is a unique vertical section through the uppermost kilometers of the martian crust. Its location, east of the Tharsis bulge, and its water-related history, fuel a great diversity of rock types in this area (Carr, M.H., Head, J.W. [2010]. Earth Planet. Sci. Lett. 294, 185-203). HiRISE and CRISM data available over the walls of the canyon were analyzed to infer the importance of magmatic and sedimentary processes through time. This contribution provides a complete morphologic and mineralogic characterization of the cross-section of rocks exposed in the canyon walls. Low-calcium pyroxene and olivine are detected in the lower portion of the walls, in association with morphologically distinct outcrops, leading to the idea that pristine Noachian crust might be exposed. Phyllosilicates are also present within the walls, but they appear to correspond to an alteration product. No proper sedimentary layers were observed within the walls of Valles Marineris at the resolution available today. All these detections are limited to the eastern portion of Valles Marineris, especially Juventae, Coprates, Capri, and Ganges chasmata. Preserved Noachian crustal material is rare on the martian surface and is rarely exposed in its pristine geologic context. Such detections lend precious information about early igneous processes. This survey also supports observations from the nearby impact crater central peaks (Quantin, C., Flahaut, J., Allemand, P. [2009]. Lunar Planet. Sci. 10; Quantin, C., Flahaut, J., Clenet, H., Allemand, P., Thomas, P. [2011]. Icarus, submitted for publication) and suggests that the western part of Valles Marineris may be cut into another material, consistent with lavas or volcanic sediments.

  11. Geologic Maps and Mapping

    NSDL National Science Digital Library

    This portal provides access to resources on geologic mapping, and to sources of geologic maps. There is an introduction to geologic mapping, which summarizes its principles and practices, and a history of United States Geological Survey (USGS) mapping activities from 1879 to the present, as well as links to papers on the values and hazards associated with geologic maps and mapping. Online sources of maps include the USGS Geologic Map Database, other federal map products (FEDMAP), state geological survey products (STATEMAP), and university map products (EDMAP).

  12. Tennessee Division of Geology

    NSDL National Science Digital Library

    This is the homepage of the Geology Division of the Tennessee Department of Environment and Conservation. It provides information on the division's programs, including geologic hazards research, public service, education programs, basic and applied research on geology and mineral resources, publication of geologic information, permitting of oil and gas wells, and regulation of Tennessee's oil and gas industry. Materials include a catalog of publications, maps, geologic bulletins, and the Public Information series of pamphlets; the Geology Division Newsletter; and information on the state's mineral industry. There is also a section on the Gray Fossil Site, an unusual assemblage of fossils and sedimentary geology encountered during road construction near the town of Gray, Tenessee.

  13. Vermont Geological Survey

    NSDL National Science Digital Library

    The Vermont Geological Survey, also known as the Division of Geology and Mineral Resources in the Department of Environmental Conservation, conducts surveys and research relating to the geology, mineral resources and topography of the State. This site provides details about the states geology with a downloadable state geologic map and key, state rock information, gold in Vermont, fossils found in the state, bedrock mapping details, stream geomorphology, the Champlain thrust fault, earthquakes, radioactive waste and links for additional information.

  14. OneGeology-Europe - The Challenges and progress of implementing a basic geological infrastructure for Europe

    NASA Astrophysics Data System (ADS)

    Asch, Kristine; Tellez-Arenas, Agnes

    2010-05-01

    OneGeology-Europe is making geological spatial data held by the geological surveys of Europe more easily discoverable and accessible via the internet. This will provide a fundamental scientific layer to the European Plate Observation System Rich geological data assets exist in the geological survey of each individual EC Member State, but they are difficult to discover and are not interoperable. For those outside the geological surveys they are not easy to obtain, to understand or to use. Geological spatial data is essential to the prediction and mitigation of landslides, subsidence, earthquakes, flooding and pollution. These issues are global in nature and their profile has also been raised by the OneGeology global initiative for the International Year of Planet Earth 2008. Geology is also a key dataset in the EC INSPIRE Directive, where it is also fundamental to the themes of natural risk zones, energy and mineral resources. The OneGeology-Europe project is delivering a web-accessible, interoperable geological spatial dataset for the whole of Europe at the 1:1 million scale based on existing data held by the European geological surveys. Proof of concept will be applied to key areas at a higher resolution and some geological surveys will deliver their data at high resolution. An important role is developing a European specification for basic geological map data and making significant progress towards harmonising the dataset (an essential first step to addressing harmonisation at higher data resolutions). It is accelerating the development and deployment of a nascent international interchange standard for geological data - GeoSciML, which will enable the sharing and exchange of the data within and beyond the geological community within Europe and globally. The geological dataset for the whole of Europe is not a centralized database but a distributed system. Each geological survey implements and hosts an interoperable web service, delivering their national harmonized geological data. These datasets are registered in a multilingual catalogue, who is one the main part of this system. This catalogue and a common metadata profile allows the discovery of national geological and applied geological maps at all scapes, Such an architecture is facilitating re-use and addition of value by a wide spectrum of users in the public and private sector and identifying, documenting and disseminating strategies for the reduction of technical and business barriers to re-use. In identifying and raising awareness in the user and provider communities, it is moving geological knowledge closer to the end-user where it will have greater societal impact and ensure fuller exploitation of a key data resource gathered at huge public expense. The project is providing examples of best practice in the delivery of digital geological spatial data to users, e.g. in the insurance, property, engineering, planning, mineral resource and environmental sectors. The scientifically attributed map data of the project will provide a pan-European base for science research and, importantly, a prime geoscience dataset capable of integration with other data sets within and beyond the geoscience domain. This presentation will demonstrate the first results of this project and will indicate how OneGeology-Europe is ensuring that Europe may play a leading role in the development of a geoscience spatial data infrastructure (SDI) globally.

  15. GWM-a ground-water management process for the U.S. Geological Survey modular ground-water model (MODFLOW-2000)

    USGS Publications Warehouse

    Ahlfeld, David P.; Barlow, Paul M.; Mulligan, Anne E.

    2005-01-01

    GWM is a Ground?Water Management Process for the U.S. Geological Survey modular three?dimensional ground?water model, MODFLOW?2000. GWM uses a response?matrix approach to solve several types of linear, nonlinear, and mixed?binary linear ground?water management formulations. Each management formulation consists of a set of decision variables, an objective function, and a set of constraints. Three types of decision variables are supported by GWM: flow?rate decision variables, which are withdrawal or injection rates at well sites; external decision variables, which are sources or sinks of water that are external to the flow model and do not directly affect the state variables of the simulated ground?water system (heads, streamflows, and so forth); and binary variables, which have values of 0 or 1 and are used to define the status of flow?rate or external decision variables. Flow?rate decision variables can represent wells that extend over one or more model cells and be active during one or more model stress periods; external variables also can be active during one or more stress periods. A single objective function is supported by GWM, which can be specified to either minimize or maximize the weighted sum of the three types of decision variables. Four types of constraints can be specified in a GWM formulation: upper and lower bounds on the flow?rate and external decision variables; linear summations of the three types of decision variables; hydraulic?head based constraints, including drawdowns, head differences, and head gradients; and streamflow and streamflow?depletion constraints. The Response Matrix Solution (RMS) Package of GWM uses the Ground?Water Flow Process of MODFLOW to calculate the change in head at each constraint location that results from a perturbation of a flow?rate variable; these changes are used to calculate the response coefficients. For linear management formulations, the resulting matrix of response coefficients is then combined with other components of the linear management formulation to form a complete linear formulation; the formulation is then solved by use of the simplex algorithm, which is incorporated into the RMS Package. Nonlinear formulations arise for simulated conditions that include water?table (unconfined) aquifers or head?dependent boundary conditions (such as streams, drains, or evapotranspiration from the water table). Nonlinear formulations are solved by sequential linear programming; that is, repeated linearization of the nonlinear features of the management problem. In this approach, response coefficients are recalculated for each iteration of the solution process. Mixed?binary linear (or mildly nonlinear) formulations are solved by use of the branch and bound algorithm, which is also incorporated into the RMS Package. Three sample problems are provided to demonstrate the use of GWM for typical ground?water flow management problems. These sample problems provide examples of how GWM input files are constructed to specify the decision variables, objective function, constraints, and solution process for a GWM run. The GWM Process runs with the MODFLOW?2000 Global and Ground?Water Flow Processes, but in its current form GWM cannot be used with the Observation, Sensitivity, Parameter?Estimation, or Ground?Water Transport Processes. The GWM Process is written with a modular structure so that new objective functions, constraint types, and solution algorithms can be added.

  16. Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory; processing, taxonomy, and quality control of benthic macroinvertebrate samples

    USGS Publications Warehouse

    Moulton, Stephen R., II; Carter, James L.; Grotheer, Scott A.; Cuffney, Thomas F.; Short, Terry M.

    2000-01-01

    Qualitative and quantitative methods to process benthic macroinvertebrate (BMI) samples have been developed and tested by the U.S. Geological Survey?s National Water Quality Laboratory Biological Group. The qualitative processing method is based on visually sorting a sample for up to 2 hours. Sorting focuses on attaining organisms that are likely to result in taxonomic identifications to lower taxonomic levels (for example, Genus or Species). Immature and damaged organisms are also sorted when they are likely to result in unique determinations. The sorted sample remnant is scanned briefly by a second person to determine if obvious taxa were missed. The quantitative processing method is based on a fixed-count approach that targets some minimum count, such as 100 or 300 organisms. Organisms are sorted from randomly selected 5.1- by 5.1-centimeter parts of a gridded subsampling frame. The sorted remnant from each sample is resorted by a second individual for at least 10 percent of the original sort time. A large-rare organism search is performed on the unsorted remnant to sort BMI taxa that were not likely represented in the sorted grids. After either qualitatively or quantitatively sorting the sample, BMIs are identified by using one of three different types of taxonomic assessment. The Standard Taxonomic Assessment is comparable to the U.S. Environmental Protection Agency Rapid Bioassessment Protocol III and typically provides Genus- or Species-level taxonomic resolution. The Rapid Taxonomic Assessment is comparable to the U.S. Environmental Protection Agency Rapid Bioassessment Protocol II and provides Familylevel and higher taxonomic resolution. The Custom Taxonomic Assessment provides Species-level resolution whenever possible for groups identified to higher taxonomic levels by using the Standard Taxonomic Assessment. The consistent use of standardized designations and notes facilitates the interpretation of BMI data within and among water-quality studies. Taxonomic identifications are quality assured by verifying all referenced taxa and randomly reviewing 10 percent of the taxonomic identifications performed weekly by Biological Group taxonomists. Taxonomic errors discovered during this review are corrected. BMI data are reviewed for accuracy and completeness prior to release. BMI data are released phylogenetically in spreadsheet format and unprocessed abundances are corrected for laboratory and field subsampling when necessary.

  17. National Park Service: Tour of Park Geology

    NSDL National Science Digital Library

    The tour of Park geologic resources includes pages specific to individual National Parks, Monuments, Recreation Areas, Preserves, Seacoasts, Reserves, and Recreation Areas. These pages are indexed by park name, state, or by one of the following topics: basin and range, caves, Colorado Plateau, fossils, glaciers, hot springs, human use, mountain building, oldest rocks, plate tectonics, river systems, sand dunes, shoreline geology, or volcanoes. Organization of each of the pages typically follows a NPS template with categories for park geology, maps, photographs, geologic research, related links, visitor information, multimedia, and "teacher features" (educational resources and links for teaching geology with National Park examples.) Common subjects that are addressed at various park sites include: minerals, rocks, fossils, cave and karst systems, coastlines, glaciers, volcanoes, faults, landforms, landslides, structures, fluvial systems, sediments, soils, stratigraphic relations, processes that form or act on geologic features and their chemical compositions, and the history of the planet and its life forms.

  18. Chemical interaction of aqueous solutions with epidote-feldspar mineral assemblages in geologic systems. II. Equilibrium constraints in metamorphic/geothermal processes

    SciTech Connect

    Bird, D.K.; Helgeson, H.C.

    1981-05-01

    Thermodynamic analysis of the system Na/sub 2/O-K/sub 2/O-CaO-FeO-Fe/sub 2/O/sub 3/-Al/sub 2/O/sub 3/-SiO/sub 2/-H/sub 2/O-HCl-CO/sub 2/ at pressures and temperatures to 5 kb and 600/sup 0/C affords quantitative description and interpretation of phase relations among epidote, garnet, plagioclase, and alkali feldspar solid solutions in hydrothermal systems. Comparison of computed and observed compositions of these minerals and coexisting fluids suggests that the calculations afford close approximation of equilibrium and mass transfer in metamorphic/geothermal processes. The standard molal enthalpies of decomposition reactions for plagioclase are of the order of -4 to -50 kcal mole/sup -1/, which requires the activity of the anorthite component of plagioclase coexisting with epidote solid solutions to increase with increasing temperature at constant pressure. In contrast, because the standard molal volumes of these reactions are also negative, a/sub CaAl/sub 2/Si/sub 2/O/sub 8// decreases with increasing pressure at constant temperature. Either stoichiometric epidote or clinozoisite is compatible with plagioclase, quartz, calcite, and an aqueous phase, but only at X/sub CO/sub 2// less than or equal to 0.2. The complex zoning commonly exhibited by both plagioclase and epidote solid solutions in geologic systems can be attributed to minor isothermal/isobaric changes in the composition of coexisting aqueous solutions. Logarithmic activity and fugacity diagrams constructed with provision for solid solution permit documentation of such changes and facilitate thermodynamic interpretation of mineral and fluid compositions in metamorphic/geothermal systems.

  19. Geologic Mapping of Vesta

    NASA Technical Reports Server (NTRS)

    Yingst, R. A.; Mest, S. C.; Berman, D. C.; Garry, W. B.; Williams, D. A.; Buczkowski, D.; Jaumann, R.; Pieters, C. M.; De Sanctis, M. C.; Frigeri, A.; Le Corre, L.; Preusker, F.; Raymond, C. A.; Reddy, V.; Russell, C. T.; Roatsch, T.; Schenk, P. M.

    2014-01-01

    We report on a preliminary global geologic map of Vesta, based on data from the Dawn spacecraft's High- Altitude Mapping Orbit (HAMO) and informed by Low-Altitude Mapping Orbit (LAMO) data. This map is part of an iterative mapping effort; the geologic map has been refined with each improvement in resolution. Vesta has a heavily-cratered surface, with large craters evident in numerous locations. The south pole is dominated by an impact structure identified before Dawn's arrival. Two large impact structures have been resolved: the younger, larger Rheasilvia structure, and the older, more degraded Veneneia structure. The surface is also characterized by a system of deep, globe-girdling equatorial troughs and ridges, as well as an older system of troughs and ridges to the north. Troughs and ridges are also evident cutting across, and spiraling arcuately from, the Rheasilvia central mound. However, no volcanic features have been unequivocally identified. Vesta can be divided very broadly into three terrains: heavily-cratered terrain; ridge-and-trough terrain (equatorial and northern); and terrain associated with the Rheasilvia crater. Localized features include bright and dark material and ejecta (some defined specifically by color); lobate deposits; and mass-wasting materials. No obvious volcanic features are evident. Stratigraphy of Vesta's geologic units suggests a history in which formation of a primary crust was followed by the formation of impact craters, including Veneneia and the associated Saturnalia Fossae unit. Formation of Rheasilvia followed, along with associated structural deformation that shaped the Divalia Fossae ridge-and-trough unit at the equator. Subsequent impacts and mass wasting events subdued impact craters, rims and portions of ridge-and-trough sets, and formed slumps and landslides, especially within crater floors and along crater rims and scarps. Subsequent to the formation of Rheasilvia, discontinuous low-albedo deposits formed or were emplaced; these lie stratigraphically above the equatorial ridges that likely were formed by Rheasilvia. The last features to be formed were craters with bright rays and other surface mantling deposits. Executed progressively throughout data acquisition, the iterative mapping process provided the team with geologic proto-units in a timely manner. However, interpretation of the resulting map was hampered by the necessity to provide the team with a standard nomenclature and symbology early in the process. With regard to mapping and interpreting units, the mapping process was hindered by the lack of calibrated mineralogic information. Topography and shadow played an important role in discriminating features and terrains, especially in the early stages of data acquisition.

  20. Geologic mapping of Vesta

    NASA Astrophysics Data System (ADS)

    Yingst, R. A.; Mest, S. C.; Berman, D. C.; Garry, W. B.; Williams, D. A.; Buczkowski, D.; Jaumann, R.; Pieters, C. M.; De Sanctis, M. C.; Frigeri, A.; Le Corre, L.; Preusker, F.; Raymond, C. A.; Reddy, V.; Russell, C. T.; Roatsch, T.; Schenk, P. M.

    2014-11-01

    We report on a preliminary global geologic map of Vesta, based on data from the Dawn spacecraft's High-Altitude Mapping Orbit (HAMO) and informed by Low-Altitude Mapping Orbit (LAMO) data. This map is part of an iterative mapping effort; the geologic map has been refined with each improvement in resolution. Vesta has a heavily-cratered surface, with large craters evident in numerous locations. The south pole is dominated by an impact structure identified before Dawn's arrival. Two large impact structures have been resolved: the younger, larger Rheasilvia structure, and the older, more degraded Veneneia structure. The surface is also characterized by a system of deep, globe-girdling equatorial troughs and ridges, as well as an older system of troughs and ridges to the north. Troughs and ridges are also evident cutting across, and spiraling arcuately from, the Rheasilvia central mound. However, no volcanic features have been unequivocally identified. Vesta can be divided very broadly into three terrains: heavily-cratered terrain; ridge-and-trough terrain (equatorial and northern); and terrain associated with the Rheasilvia crater. Localized features include bright and dark material and ejecta (some defined specifically by color); lobate deposits; and mass-wasting materials. No obvious volcanic features are evident. Stratigraphy of Vesta's geologic units suggests a history in which formation of a primary crust was followed by the formation of impact craters, including Veneneia and the associated Saturnalia Fossae unit. Formation of Rheasilvia followed, along with associated structural deformation that shaped the Divalia Fossae ridge-and-trough unit at the equator. Subsequent impacts and mass wasting events subdued impact craters, rims and portions of ridge-and-trough sets, and formed slumps and landslides, especially within crater floors and along crater rims and scarps. Subsequent to the formation of Rheasilvia, discontinuous low-albedo deposits formed or were emplaced; these lie stratigraphically above the equatorial ridges that likely were formed by Rheasilvia. The last features to be formed were craters with bright rays and other surface mantling deposits. Executed progressively throughout data acquisition, the iterative mapping process provided the team with geologic proto-units in a timely manner. However, interpretation of the resulting map was hampered by the necessity to provide the team with a standard nomenclature and symbology early in the process. With regard to mapping and interpreting units, the mapping process was hindered by the lack of calibrated mineralogic information. Topography and shadow played an important role in discriminating features and terrains, especially in the early stages of data acquisition.

  1. GEOLOGY, August 2008 663 INTRODUCTION

    E-print Network

    Gilli, Adrian

    GEOLOGY, August 2008 663 INTRODUCTION Putative nanobacterial fossils and grainy textures have been confocal laser scanning microscopy (CLSM), scanning electron microscope equipped with cryogenic preparation to distinguish actual structures from arti- facts due to the sample preparation processes. CLSM and cryo

  2. Weird Geology: The Devil's Tower

    NSDL National Science Digital Library

    Lee Krystek

    This page features a brief introduction to the several theories about the geological processes that formed Devil's Tower, which rises 1,267 feet above the nearby Belle Fourche River and is still considered a sacred place by some Native American Tribes. Information on climbing the tower as well as images and a cross section are provided.

  3. Geological rhythms and cometary impacts

    NASA Technical Reports Server (NTRS)

    Rampino, M. R.; Strothers, R. B.

    1984-01-01

    Time series analysis reveals two dominant, long-term periodicities approximately equal to 32 and 260 million years in the known series of geological and biological upheavals during the Phanerozoic Eon. The cycles of these episodes agree in period and phase with the cycles of impact cratering on Earth, suggesting that periodic comet impacts strongly influence Earth processes.

  4. Fundamentals High Resolution

    E-print Network

    Simons, Jack

    Fundamentals of High Resolution Pulse and Fourier Transform NMR Spectroscopy #12;#12;iii 1. ........................................................................................... 10 5. The Effects of Radio Frequency Fields

  5. Glossary of Geologic Terms

    NSDL National Science Digital Library

    This page from Iowa State University presents a general glossary of geologic terms. The site would be a good reference for geology coursework. This glossary of geologic terms is based on the glossary in Earth: An Introduction to Geologic Change, by S. Judson and S.M. Richardson (Englewood Cliffs, NJ, Prentice Hall, 1995). Where possible, definitions conform generally, and in some cases specifically, to definitions given in Robert L Bates and Julia A Jackson (editors), Glossary of Geology, 3rd ed., American Geological Institute, Alexandria, Virginia, 1987.

  6. A Geological Wonder: Niagara Falls

    NSDL National Science Digital Library

    This lesson plan is part of the DiscoverySchool.com lesson plan library for grades 9-12. It focuses on the geological history of the Niagara Falls area, as well as the physical and geological processes that have formed this region. It includes objectives, materials, procedures, discussion questions, evaluation ideas, performing extensions, suggested readings, and vocabulary. There are videos available to order which complement this lesson, audio vocabulary, and links to teaching tools for making custom quizzes, worksheets, puzzles and lesson plans.

  7. Principles of Historical Geology Geology 331

    E-print Network

    Kammer, Thomas

    of a valley can be correlated. · This principle is used to trace coal seams from one mountain to the next in West Virginia. #12;Original Lateral Continuity #12;Geology Field Camp in the Badlands of South Dakota Rocks #12;James Hutton, 18th Century founder of Geology #12;Siccar Point, Scotland, where Hutton

  8. SURVEY GUIDE SURVEY FUNDAMENTALS

    E-print Network

    Shapiro, Vadim

    SURVEY GUIDE 1 SURVEY FUNDAMENTALS A GUIDE TO DESIGNING AND IMPLEMENTING SURVEYS #12;S U R V E Y GU I D E OFFICE OF QUALITY IMPROVEMENT SURVEY FUNDAMENTALS This guide describes in non-technical terms the underlying principles of good survey design and implementation. Clear, simple explanations lead the reader

  9. Utah Geological Survey: Teaching Geology Resources

    NSDL National Science Digital Library

    From Arches National Park to the towering cliffs at Castle Rock Campground, Utah has some remarkable geology on display. The Utah Geological Survey decided to draw on these fantastic "outdoor laboratories" and create a set of resources designed for science educators. While some of the resources are geared towards users in Utah, many of the sections contain helpful overviews that will help all educators remain on a steady foundation of geologic knowledge. One key area on the site is the "Earthquakes & Geologic Hazards" section. Here, visitors can find well-composed and straight forward summaries on topics like liquefaction, ground cracks, and fault lines. Moving on to the "Teacher Resources" area, visitors will find the delightful "Glad You Asked" articles and the very useful "Teacher's Corner" column which provides information on reading a stone wall and geologic stretching.

  10. Geology. Grade 6. Anchorage School District Elementary Science Program.

    ERIC Educational Resources Information Center

    Anchorage School District, AK.

    This resource book introduces sixth-grade children to the environment by studying rocks and other geological features. Nine lessons are provided on a variety of topics including: (1) geologic processes; (2) mountain building; (3) weathering; (4) geologic history and time; (5) plate tectonics; (6) rocks and minerals; (7) mineral properties; (8)…

  11. Unraveling Geological History: Glaciers and Faults at Discovery Park, Seattle

    NSDL National Science Digital Library

    Trileigh Tucker

    This introductory geology field exercise asks students to make individual observations about parts of an outcrop, then combine their observations in larger teams to interpret the overall geological history of the exposure. Content learning includes stratigraphy, faulting, and local geologic history; process learning includes data gathering and recording, hypothesis formation, and outlining helpful evidence that could be gathered in the future.

  12. GSA Geologic Time Scale

    NSDL National Science Digital Library

    1999-01-01

    This Geological Society of America (GSA) site contains a detailed geologic time scale as an educational resource. It may be downloaded to a larger size, and includes all Eras, Eons, Periods, Epochs and ages as well as magnetic polarity information.

  13. Geophysics & Geology Inspected.

    ERIC Educational Resources Information Center

    Neale, E. R. W.

    1981-01-01

    Summarizes findings of a recently published report of the Canadian Geoscience Council, which includes the following topics regarding college geology: facilities; teaching; undergraduate enrollments; postgraduate enrollments; geologic research; and integration of Canadian geoscience with other countries. (CS)

  14. Geologic spatial analysis

    SciTech Connect

    Thiessen, R.L.; Eliason, J.R.

    1989-01-01

    This report describes the development of geologic spatial analysis research which focuses on conducting comprehensive three-dimensional analysis of regions using geologic data sets that can be referenced by latitude, longitude, and elevation/depth. (CBS)

  15. Introduction Systems Engineering Fundamentals ENGINEERING

    E-print Network

    Rhoads, James

    Introduction Systems Engineering Fundamentals i SYSTEMS ENGINEERING FUNDAMENTALS January 2001;Systems Engineering Fundamentals Introduction ii #12;Introduction Systems Engineering Fundamentals iii ............................................................................................................................................. iv PART 1. INTRODUCTION Chapter 1. Introduction to Systems Engineering Management

  16. Physiography, geology, and land cover of four watersheds in eastern Puerto Rico: Chapter A in Water quality and landscape processes of four watersheds in eastern Puerto Rico

    USGS Publications Warehouse

    Murphy, Sheila F.; Stallard, Robert F.; Larsen, Matthew C.; Gould, William A.

    2012-01-01

    Four watersheds with differing geology and land cover in eastern Puerto Rico have been studied on a long-term basis by the U.S. Geological Survey to evaluate water, energy, and biogeochemical budgets. These watersheds are typical of tropical, island-arc settings found in many parts of the world. Two watersheds are located on coarse-grained granitic rocks that weather to quartz- and clay-rich, sandy soils, and two are located on fine-grained volcanic rocks and volcaniclastic sedimentary rocks that weather to quartz-poor, fine-grained soils. For each bedrock type, one watershed is covered with mature forest, and the other watershed, like most of Puerto Rico, has transformed from relatively undisturbed pre-European forest to intensive agriculture in the 19th and early 20th centuries, and further to ongoing reforestation that began in the middle of the 20th century. The comparison of water chemistry and hydrology in these watersheds allows an evaluation of the effects of land-use history and geology on hydrologic regimes and erosion rates. This chapter describes the physiography, geology, and land cover of the four watersheds and provides background information for the remaining chapters in this volume.

  17. South Dakota Geological Survey

    NSDL National Science Digital Library

    The mission of the geological survey is to conduct geologic studies, hydrologic studies, and research, and to collect, correlate, preserve, interpret, and disseminate information, leading to a better understanding of the geology and hydrology of South Dakota. Information includes maps of relief, geology, ground water, and earthquakes; projects such as well testing, hydrology, and aquifers; and searchable databases, such as lithologic logs, digital base, and water quality. Links are provided for more information.

  18. Louisiana Geological Survey

    NSDL National Science Digital Library

    The Louisiana Geological Survey, located at Louisiana State University, developed this website to promote its goal to provide geological and environmental data that will allow for environmentally sound natural resource development and economic decisions. Users can find general information about the Survey's mission, staff, plan, and history. The website features the research and publications of the Basin Research, Cartographic, Coastal, Geologic Mapping, and Water and Environmental sections. Researchers can discover stratigraphic charts of Louisiana, information on lignite resources, and other geologic data.

  19. South Carolina Geological Survey

    NSDL National Science Digital Library

    The South Carolina Geological Survey (SCGS) homepage contains information about state mapping, education and outreach programs, and recent news. For educators, there is the Earth Science education series of publications which includes presentations and page-size graphics on such topics as earthquakes, plate tectonics, geologic time, fossils, and others. Other materials include information on mineral resources, links to organizations in and about South Carolina geology, the South Carolina core repository, the Geologic Map of South Carolina, and others.

  20. Iowa Geological Survey Bureau

    NSDL National Science Digital Library

    The Iowa Geological Survey Bureau (GSB) homepage contains: general information about the geology of Iowa; the Natural Resources Geographic Information System, which is a collection of databases on geology and water wells; and information about GSB staff, geologic studies, water monitoring programs, and services. There are maps, photographs, general interest articles, technical abstracts, lists of available publications, and an on-line book about the natural resource history of Iowa.

  1. Geological Survey Program

    NSDL National Science Digital Library

    If your research or interests lie in the geology of South Dakota, then the state's Geological Survey Program Web site is for you. Offered are online publications and maps, a geologic reference database, a lithologic logs database, digital base maps, a water quality database, and several other quality information sources worth checking out.

  2. Co2 geological sequestration

    SciTech Connect

    Xu, Tianfu

    2004-11-18

    Human activities are increasingly altering the Earth's climate. A particular concern is that atmospheric concentrations of carbon dioxide (CO{sub 2}) may be rising fast because of increased industrialization. CO{sub 2} is a so-called ''greenhouse gas'' that traps infrared radiation and may contribute to global warming. Scientists project that greenhouse gases such as CO{sub 2} will make the arctic warmer, which would melt glaciers and raise sea levels. Evidence suggests that climate change may already have begun to affect ecosystems and wildlife around the world. Some animal species are moving from one habitat to another to adapt to warmer temperatures. Future warming is likely to exceed the ability of many species to migrate or adjust. Human production of CO{sub 2} from fossil fuels (such as at coal-fired power plants) is not likely to slow down soon. It is urgent to find somewhere besides the atmosphere to put these increased levels of CO{sub 2}. Sequestration in the ocean and in soils and forests are possibilities, but another option, sequestration in geological formations, may also be an important solution. Such formations could include depleted oil and gas reservoirs, unmineable coal seams, and deep saline aquifers. In many cases, injection of CO2 into a geological formation can enhance the recovery of hydrocarbons, providing value-added byproducts that can offset the cost of CO{sub 2} capture and sequestration. Before CO{sub 2} gas can be sequestered from power plants and other point sources, it must be captured. CO{sub 2} is also routinely separated and captured as a by-product from industrial processes such as synthetic ammonia production, H{sub 2} production, and limestone calcination. Then CO{sub 2} must be compressed into liquid form and transported to the geological sequestration site. Many power plants and other large emitters of CO{sub 2} are located near geological formations that are amenable to CO{sub 2} sequestration.

  3. Significant achievements in the planetary geology program

    NASA Technical Reports Server (NTRS)

    Head, J. W. (editor)

    1984-01-01

    Recent developments in planetology research are summarized. Important developments are summarized in topics ranging from solar system evolution, comparative planetology, and geologic processes active on other planetary bodies, to techniques and instrument development for exploration.

  4. Christopher U.S. Geological Survey

    E-print Network

    desalinization loop in Chula Vista, California. Hydrologist U.S. Geological Survey, Tucson, Arizona. May 2000-controlled rivers. · Analyzed debris flows and debris-flow processes in arid and mountainous regions from convective

  5. Effects of Rock Type and Geologic Process on the Structure and Evolution of Nano, Meso and Micro-Scale Porosity: A (U)SANS, SEM/BSE Analysis

    NASA Astrophysics Data System (ADS)

    Anovitz, L.; Wang, H.; Cole, D. R.; Rother, G.

    2012-12-01

    The microstructure and evolution of porosity in time and space play a critical role in many geologic processes, including the migration and retention of water, gas and hydrocarbons, the evolution of hydrothermal systems, weathering, diagenesis and metamorphism, as well as technological processes such as CO2 sequestration, shale gas and secondary oil recovery. The size, distribution and connectivity of these confined geometries collectively dictate how fluids migrate into and through these micro- and nanoenvironments, wet and react with mineral surfaces. (Ultra)small-angle neutron scattering and autocorrelations derived from SEM/BSE imaging provide a method of quantifying pore structures in a statistically significant manner from the nanometer to the centimeter scale. Data from this approach suggests that there are significant primary and evolutionary differences between the multiscale pore structures of carbonate and clastic rocks. Our work on the St. Peter sandstone shows total porosity correlates with changes in pores structure including pore size ratios, surface fractal dimensions, and lacunarity. There is no evidence of mass-fractal scattering and while previous scattering data from sandstones suggest scattering is dominated by surface fractal behavior over many orders of magnitude, our data show both fractal and pseudo-fractals. Larger pores fill at a faster rate than small pores as overgrowths form, leading to an increase in the small/large pore ratio. Overall, therefore, the relative importance of fluid reactions in confined geometries is likely to increase with increased silcrete formation. The changes observed with overgrowth formation in sandstones contrast with available data for metamorphism of chemical sediments (limestones) in both the Marble Canyon contact aureole, TX (Anovitz et al., 2009), and the Hatrurim Fm. (the Mottled Zone), Israel. The unmetamorphosed limestones both show distinct multifractal scattering patterns at larger scales, and true surface fractals at smaller scales. Total porosity increases with metamorphism, as does the surface area to volume ratio. The mass fractal dimension increases with metamorphic grade. In the Hatrurim the surface fractal dimension also increase suggesting that increases in pore mass density and formation of less branching pore networks are accompanied by a roughening of pore/grain interfaces. Ds changes are more complex at Marble Canyon, possibly due to hydrothermal processes. Pore evolution during combustion metamorphism is also characterized by reduced contributions from small-scale pores to the cumulative porosity in the high-grade rocks. The evolution of pore/grain microstructures may be correlated to the growth (nucleation) of high-temperature phases that preferentially close small pores, producing a rougher morphology with increasing temperature. The transition to a rough morphology may be a consequence of pore/grain surface free energies that are smaller than those that arise from heterogeneous phase contacts. Large-scale pores may also develop at the expense of small-scale pores. [1] Anovitz et al. (2009) Geochimica et Cosmochimica Acta 73, 7303-7324. Research sponsored by the Division of Chemical Sciences, Geosciences, and Biosciences, Office of Basic Energy Sciences, U.S. Department of Energy.

  6. Phylogeographic patterns of genetic diversity in eastern Mediterranean water frogs have been determined by geological processes and climate change in the Late Cenozoic.

    PubMed

    Ak?n, Ci?dem; Bilgin, C Can; Beerli, Peter; Westaway, Rob; Ohst, Torsten; Litvinchuk, Spartak N; Uzzell, Thomas; Bilgin, Metin; Hotz, Hansjürg; Guex, Gaston-Denis; Plötner, Jörg

    2010-11-01

    AIM: Our aims were to assess the phylogeographic patterns of genetic diversity in eastern Mediterranean water frogs and to estimate divergence times using different geological scenarios. We related divergence times to past geological events and discuss the relevance of our data for the systematics of eastern Mediterranean water frogs. LOCATION: The eastern Mediterranean region. METHODS: Genetic diversity and divergence were calculated using sequences of two protein-coding mitochondrial (mt) genes: ND2 (1038 bp, 119 sequences) and ND3 (340 bp, 612 sequences). Divergence times were estimated in a Bayesian framework under four geological scenarios representing alternative possible geological histories for the eastern Mediterranean. We then compared the different scenarios using Bayes factors and additional geological data. RESULTS: Extensive genetic diversity in mtDNA divides eastern Mediterranean water frogs into six main haplogroups (MHG). Three MHGs were identified on the Anatolian mainland; the most widespread MHG with the highest diversity is distributed from western Anatolia to the northern shore of the Caspian Sea, including the type locality of Pelophylax ridibundus. The other two Anatolian MHGs are restricted to south-eastern Turkey, occupying localities west and east of the Amanos mountain range. One of the remaining three MHGs is restricted to Cyprus; a second to the Levant; the third was found in the distribution area of European lake frogs (P. ridibundus group), including the Balkans. MAIN CONCLUSIONS: Based on geological evidence and estimates of genetic divergence we hypothesize that the water frogs of Cyprus have been isolated from the Anatolian mainland populations since the end of the Messinian salinity crisis (MSC), i.e. since c. 5.5-5.3 Ma, while our divergence time estimates indicate that the isolation of Crete from the mainland populations (Peloponnese, Anatolia) most likely pre-dates the MSC. The observed rates of divergence imply a time window of c. 1.6-1.1 million years for diversification of the largest Anatolian MHG; divergence between the two other Anatolian MHGs may have begun about 3.0 Ma, apparently as a result of uplift of the Amanos Mountains. Our mtDNA data suggest that the Anatolian water frogs and frogs from Cyprus represent several undescribed species. PMID:22473251

  7. Phylogeographic patterns of genetic diversity in eastern Mediterranean water frogs have been determined by geological processes and climate change in the Late Cenozoic

    PubMed Central

    Ak?n, Ēi?dem; Bilgin, C. Can; Beerli, Peter; Westaway, Rob; Ohst, Torsten; Litvinchuk, Spartak N.; Uzzell, Thomas; Bilgin, Metin; Hotz, Hansjürg; Guex, Gaston-Denis; Plötner, Jörg

    2010-01-01

    Aim Our aims were to assess the phylogeographic patterns of genetic diversity in eastern Mediterranean water frogs and to estimate divergence times using different geological scenarios. We related divergence times to past geological events and discuss the relevance of our data for the systematics of eastern Mediterranean water frogs. Location The eastern Mediterranean region. Methods Genetic diversity and divergence were calculated using sequences of two protein-coding mitochondrial (mt) genes: ND2 (1038 bp, 119 sequences) and ND3 (340 bp, 612 sequences). Divergence times were estimated in a Bayesian framework under four geological scenarios representing alternative possible geological histories for the eastern Mediterranean. We then compared the different scenarios using Bayes factors and additional geological data. Results Extensive genetic diversity in mtDNA divides eastern Mediterranean water frogs into six main haplogroups (MHG). Three MHGs were identified on the Anatolian mainland; the most widespread MHG with the highest diversity is distributed from western Anatolia to the northern shore of the Caspian Sea, including the type locality of Pelophylax ridibundus. The other two Anatolian MHGs are restricted to south-eastern Turkey, occupying localities west and east of the Amanos mountain range. One of the remaining three MHGs is restricted to Cyprus; a second to the Levant; the third was found in the distribution area of European lake frogs (P. ridibundus group), including the Balkans. Main conclusions Based on geological evidence and estimates of genetic divergence we hypothesize that the water frogs of Cyprus have been isolated from the Anatolian mainland populations since the end of the Messinian salinity crisis (MSC), i.e. since c. 5.5-5.3 Ma, while our divergence time estimates indicate that the isolation of Crete from the mainland populations (Peloponnese, Anatolia) most likely pre-dates the MSC. The observed rates of divergence imply a time window of c. 1.6-1.1 million years for diversification of the largest Anatolian MHG; divergence between the two other Anatolian MHGs may have begun about 3.0 Ma, apparently as a result of uplift of the Amanos Mountains. Our mtDNA data suggest that the Anatolian water frogs and frogs from Cyprus represent several undescribed species. PMID:22473251

  8. Arkansas Geological Survey

    NSDL National Science Digital Library

    The Arkansas Geological Survey (AGS) homepage aims to develop and provide knowledge of the geology and hydrogeology of the State, and to stimulate development and effective management and utilization of the mineral, fossil-fuel, and water resources of Arkansas while protecting the environment. The AGC collects and disperses geologic data consisting of geologic maps, historical data concerning resources, and various datasets concerning water, fossil-fuel, and mineral resources of Arkansas. The site contains publications that can be ordered, sections about Arkansas geology, a list of mineral producers of Arkansas, and reports on mineral resources.

  9. Virtual-Geology.Info

    NSDL National Science Digital Library

    At virtual-geology.info, Roger Suthren, a professor at Oxford Brookes University, offers educational materials on geologic phenomena throughout the world. Users can take virtual field trips to study the geology of Scotland, Alaska, and France. In the Regional Geology link, visitors can view wonderful pictures of the volcanoes of Germany, Italy, France, and Greece. Educators can find images of sediments and sedimentary rocks which can be used in a variety of classroom exercises. The website supplies descriptions and additional educational links about sedimentology and environmental geology.

  10. Fundamentals of Petroleum.

    ERIC Educational Resources Information Center

    Bureau of Naval Personnel, Washington, DC.

    Basic information on petroleum is presented in this book prepared for naval logistics officers. Petroleum in national defense is discussed in connection with consumption statistics, productive capacity, world's resources, and steps in logistics. Chemical and geological analyses are made in efforts to familiarize methods of refining, measuring,…

  11. Fundamental Thermodynamics of Actinide-Bearing Mineral Waste Forms

    Microsoft Academic Search

    Mark A

    2000-01-01

    The landmark record of decision in January 2000 by the US Department of Energy stated that at least 17 tons of surplus weapons plutonium will be converted to a mineral waste material and disposed of in a geological repository similar to the proposed Yucca Mountain nuclear waste site in Nevada. The need for fundamental thermodynamic properties (e.g., entropy, enthalpy and

  12. Streamflow and water-quality conditions including geologic sources and processes affecting selenium loading in the Toll Gate Creek watershed, Aurora, Arapahoe County, Colorado, 2007

    USGS Publications Warehouse

    Paschke, Suzanne S.; Runkel, Robert L.; Walton-Day, Katherine; Kimball, Briant A.; Schaffrath, Keelin R.

    2013-01-01

    Toll Gate Creek is a perennial stream draining a suburban area in Aurora, Colorado, where selenium concentrations have consistently exceeded the State of Colorado aquatic-life standard for selenium of 4.6 micrograms per liter since the early 2000s. In cooperation with the City of Aurora, Colorado, Utilities Department, a synoptic water-quality study was performed along an 18-kilometer reach of Toll Gate Creek extending from downstream from Quincy Reservoir to the confluence with Sand Creek to develop a detailed understanding of streamflow and concentrations and loads of selenium in Toll Gate Creek. Streamflow and surface-water quality were characterized for summer low-flow conditions (July–August 2007) using four spatially overlapping synoptic-sampling subreaches. Mass-balance methods were applied to the synoptic-sampling and tracer-injection results to estimate streamflow and develop spatial profiles of concentration and load for selenium and other chemical constituents in Toll Gate Creek surface water. Concurrent groundwater sampling determined concentrations of selenium and other chemical constituents in groundwater in areas surrounding the Toll Gate Creek study reaches. Multivariate principal-component analysis was used to group samples and to suggest common sources for dissolved selenium and major ions. Hydrogen and oxygen stable-isotope ratios, groundwater-age interpretations, and chemical analysis of water-soluble paste extractions from core samples are presented, and interpretation of the hydrologic and geochemical data support conclusions regarding geologic sources of selenium and the processes affecting selenium loading in the Toll Gate Creek watershed. Streamflow conditions observed and measured during the synoptic water-quality study represent summer base-flow conditions and rainfall conditions for July 2007. The lack of large tributary inflows and the spatial distribution of small tributary inflows, seeps, and springs indicate that diffuse and discrete groundwater inflow supports streamflow during low-flow conditions along the entire 18-kilometer stream reach. Concentrations of dissolved selenium within all subreaches of Toll Gate Creek exceeded the Colorado aquatic-life standard of 4.6 micrograms per liter in 2007. Concentrations of selenium in the upper portion of the Toll Gate Headwaters subreach (TGH) remained close to the aquatic-life standard at about 5 micrograms per liter. Downstream from a concrete-lined channel section, inflows with selenium concentrations greater than the stream contribute selenium load to surface water. However, stream selenium concentrations were less than 20 micrograms per liter all along Toll Gate Creek. Concentrations of selenium in groundwater were in general substantially greater than the Colorado aquatic-life standard of 4.6 micrograms per liter and at some locations were greater than the U.S. Environmental Protection Agency primary drinking-water standard for selenium of 50 micrograms per liter. The distribution of selenium concentrations in groundwater, springs, and the 11 inflows with the greatest selenium concentrations indicates that shallow groundwater in surficial materials and the Denver Formation bedrock is a source of selenium loading to Toll Gate Creek and that selenium loading is distributed along the entire length of the study reach downstream from the concrete-lined channel. Water-quality and solids-sampling results from this study indicate weathering processes release water-soluble selenium from the underlying Denver Formation claystone bedrock with subsequent cycling of selenium in the aquatic environment of Toll Gate Creek. Exposure of the Denver Formation selenium-bearing bedrock to oxidizing atmospheric conditions, surface water, and groundwater, oxidizes selenide, held as a trace element in pyrite or in complexes with organic matter, to selenite and selenate. Secondary weathering products including iron oxides and selenium-bearing salts have accumulated in the weathered zone in the semiarid climate and also can serve as sources or sinks of selenium. P

  13. Mitochondrial Morphology and Fundamental Parameters of the Mitochondrial Respiratory Chain Are Altered in Caenorhabditis elegans Strains Deficient in Mitochondrial Dynamics and Homeostasis Processes

    PubMed Central

    Luz, Anthony L.; Rooney, John P.; Kubik, Laura L.; Gonzalez, Claudia P.; Song, Dong Hoon; Meyer, Joel N.

    2015-01-01

    Mitochondrial dysfunction has been linked to myriad human diseases and toxicant exposures, highlighting the need for assays capable of rapidly assessing mitochondrial health in vivo. Here, using the Seahorse XFe24 Analyzer and the pharmacological inhibitors dicyclohexylcarbodiimide and oligomycin (ATP-synthase inhibitors), carbonyl cyanide 4-(trifluoromethoxy) phenylhydrazone (mitochondrial uncoupler) and sodium azide (cytochrome c oxidase inhibitor), we measured the fundamental parameters of mitochondrial respiratory chain function: basal oxygen consumption, ATP-linked respiration, maximal respiratory capacity, spare respiratory capacity and proton leak in the model organism Caenhorhabditis elegans. Since mutations in mitochondrial homeostasis genes cause mitochondrial dysfunction and have been linked to human disease, we measured mitochondrial respiratory function in mitochondrial fission (drp-1)-, fusion (fzo-1)-, mitophagy (pdr-1, pink-1)-, and electron transport chain complex III (isp-1)-deficient C. elegans. All showed altered function, but the nature of the alterations varied between the tested strains. We report increased basal oxygen consumption in drp-1; reduced maximal respiration in drp-1, fzo-1, and isp-1; reduced spare respiratory capacity in drp-1 and fzo-1; reduced proton leak in fzo-1 and isp-1; and increased proton leak in pink-1 nematodes. As mitochondrial morphology can play a role in mitochondrial energetics, we also quantified the mitochondrial aspect ratio for each mutant strain using a novel method, and for the first time report increased aspect ratios in pdr-1- and pink-1-deficient nematodes. PMID:26106885

  14. Ohio Geological Survey

    NSDL National Science Digital Library

    This is the homepage of the Ohio Geological Survey. Materials available through the site include a variety of publications, particularly the Survey's reports, bulletins, information circulars, guidebooks, and many others. There is an extensive selection of maps, including topographic maps in several scales, and downloadable geologic maps of several themes (drift thickness, bedrock geology, karst areas, glacial geology, and many others), as well as digital maps and data. The interactive maps section features online map viewers of abandoned mines, earthquake epicenters, surficial geology, geology of Lake Erie, and others. The educational resources page has links to the 'Hands On Earth' series of activities, GeoFacts (short bulletins on Ohio geological topics), nontechnical educational leaflets, field guides, and links to other publications, rock and mineral clubs, educational associations, and related websites. There is also a link to the Ohio Seismic Network, a network of seismograph stations located at colleges, universities, and other institutions that collects and disseminates information about earthquakes in Ohio.

  15. Fundamental Laws of Algebra

    NSDL National Science Digital Library

    Blohowiak, Chad

    2005-01-01

    This learning object from Wisc-Online covers the fundamental laws of algebra. The interactive activity includes slides which cover the following topics: the commutative, associative and distributive laws as applied to addition and multiplication.

  16. Fundamental strings in SFT

    E-print Network

    L. Bonora; C. Maccaferri; R. J. Scherer Santos; D. D. Tolla

    2005-01-14

    In this letter we show that vacuum string field theory contains exact solutions that can be interpreted as macroscopic fundamental strings. They are formed by a condensate of infinitely many completely space-localized solutions (D0-branes).

  17. Fundamental strings in SFT

    Microsoft Academic Search

    L. Bonora; C. Maccaferri; R. J. Scherer Santos; D. D. Tolla

    2005-01-01

    In this Letter we show that vacuum string field theory contains exact solutions that we propose to interpret as macroscopic fundamental strings. They are formed by a condensate of infinitely many completely space-localized solutions (D0-branes).

  18. Fundamental strings in SFT

    E-print Network

    Bonora, L; Santos, R J S; Tolla, D D

    2005-01-01

    In this letter we show that vacuum string field theory contains exact solutions that can be interpreted as macroscopic fundamental strings. They are formed by a condensate of infinitely many completely space-localized solutions (D0-branes).

  19. Fundamental Aeronautics Hypersonics Project

    E-print Network

    for the National Aeronautics and Space Administration (NASA) Aeronautics Research Mission Directorate (ARMDFundamental Aeronautics Hypersonics Project Reference Document Principal Investigator: James and detailed content of a comprehensive Fundamental Aeronautics Hypersonics research project. It contains

  20. Fundamentals of NMR

    NSDL National Science Digital Library

    James, Thomas L.

    This e-text presents an introduction to the fundamentals of NMR covering magnetic resonance, pulsed NMR, relaxation, chemical shift, spin-spin coupling, the nuclear Overhauser effect and chemical exchange. The document may be downloaded in PDF format.

  1. Fundamentals of traffic engineering

    SciTech Connect

    Homburger, W.S.; Kell, J.H.

    1984-01-01

    This book discusses the fundamentals of traffic engineering. It covers traffic engineering characteristics and studies, control devices and their application, planning and design, control systems and strategies, environmental energy aspects, human factors, traffic engineering administration.

  2. Map Showing Geology, Oil and Gas Fields and Geologic Provinces of Africa, Ver. 2.0

    NSDL National Science Digital Library

    Ahlbrandt, Thomas S.

    The US Geological Survey offers the Map Showing Geology, Oil and Gas Fields and Geologic Provinces of Africa Web site and report. The agency's goal for the pieces includes assessing the undiscovered and technically recoverable oil and gas resources of the world. The site includes various descriptions of what the map depicts and how data was processed using Geographic Information Systems. Once the interactive map is activated, users can search and click the map of Africa to view geologic provinces, oil and gas fields, as well as the various surface geological classifications. Although the interface is a bit cumbersome and works best with a fast Internet connection, the unique information provided should draw the attention of those interested in geology. [JAB

  3. Geological consequences of superplumes

    SciTech Connect

    Larson, R.L. (Univ. of Rhode Island, Narragansett (United States))

    1991-10-01

    Superplumes are suggested to have caused the period of constant normal magnetic polarity in mid-Cretaceous time (124-83 Ma) and, possibly, the period of constant reversed polarity in Pennsylvania-Permian time (323-248 Ma). These times coincide with increases in world temperature, deposition of black shales, oil generation, and eustatic sea level in the mid-Cretaceous, and increased coal generation and gas accumulation in the Pennsylvanian-Permian, accompanied by an intracratonic Pennsylvanian transgression of epicontinental seas. These geologic anomalies are associated with episodes of increased world-wide ocean-crust production and mantle outgassing, especially of carbon and nutrients. These superplumes originated just above the core-mantle boundary, significantly increased convection in the outer core, and stopped the magnetic field reversal process for 41 m.y. in the Cretaceous and 75 m.y. in Pennsylvanian-Permian time.

  4. Carbon dioxide reaction processes in a model brine aquifer at 200 °C and 200 bars: implications for geologic sequestration of carbon

    Microsoft Academic Search

    John P. Kaszuba; David R. Janecky; Marjorie G. Snow

    2003-01-01

    The reactive behavior of supercritical CO2 under conditions relevant to geologic storage and sequestration of C is largely unknown. Experiments were conducted in a flexible cell hydrothermal apparatus to determine the extent of fluid–rock reactions, in addition to carbonate mineral precipitation, that may occur in a brine aquifer–aquitard system that simulates a saline aquifer storage scenario. The system was held

  5. Contribution of seismic processing to put up the scaffolding for the 3-dimensional study of deep sedimentary basins: the fundaments of trans-national 3D modelling in the project GeoMol

    NASA Astrophysics Data System (ADS)

    Capar, Laure

    2013-04-01

    Within the framework of the transnational project GeoMol geophysical and geological information on the entire Molasse Basin and on the Po Basin are gathered to build consistent cross-border 3D geological models based on borehole evidence and seismic data. Benefiting from important progress in seismic processing, these new models will provide some answers to various questions regarding the usage of subsurface resources, as there are geothermal energy, CO2 and gas storage, oil and gas production, and support decisions-making to national and local administrations as well as to industries. More than 28 000 km of 2D seismic lines are compiled reprocessed and harmonized. This work faces various problems like the vertical drop of more than 700 meters between West and East of the Molasse Basin and to al lesser extent in the Po Plain, the heterogeneities of the substratum, the large disparities between the period and parameters of seismic acquisition, and depending of their availability, the use of two types of seismic data, raw and processed seismic data. The main challenge is to harmonize all lines at the same reference level, amplitude and step of signal processing from France to Austria, spanning more than 1000 km, to avoid misfits at crossing points between seismic lines and artifacts at the country borders, facilitating the interpretation of the various geological layers in the Molasse Basin and Po Basin. A generalized stratigraphic column for the two basins is set up, representing all geological layers relevant to subsurface usage. This stratigraphy constitutes the harmonized framework for seismic reprocessing. In general, processed seismic data is available on paper at stack stage and the mandatory information to take these seismic lines to the final stage of processing, the migration step, are datum plane and replacement velocity. However several datum planes and replacement velocities were used during previous processing projects. Our processing sequence is to first digitize the data, to have them in SEG-Y format. The second step is to apply some post-stack processing to obtain a good data quality before the final migration step. The third step is the final migration, using optimized migration velocities and the fourth step is the post-migration processing. In case of raw seismic data, the mandatory information for processing is made accessible, like from observer logs, coordinates and field seismic data. The processing sequence in order to obtain the final usable version of the seismic line is based on a pre-stack time migration. A complex processing sequence is applied. One main issue is to deal with the significant changes in the topography along the seismic lines and in the first twenty meter layer, this low velocity zone (LVZ) or weathered zone, where some lateral velocity variations occur and disturb the wave propagation, therefore the seismic signal. In seismic processing, this matter is solved by using the static corrections which allow removing these effects of lateral velocity variations and the effects of topography. Another main item is the good determination of root mean square velocities for migration, to improve the final result of seismic processing. Within GeoMol, generalized 3D velocity models of stack velocities are calculated in order to perform a rapid time-depth conversion. In final, all seismic lines of the project GeoMol will be at the same level of processing, the migration level. But to tie all these lines, a single appropriate datum plane and replacement velocity for the entire Molasse Basin and Po Plain, respectively, have to be carefully set up, to avoid misties at crossing points. The reprocessing and use of these 28 000 km of seismic lines in the project GeoMol provide the pivotal database to build a 3D framework model for regional subsurface information on the Alpine foreland basins (cf. Rupf et al. 2013, EGU2013-8924). The project GeoMol is co-funded by the Alpine Space Program as part of the European Territorial Cooperation 2007-2013. The project integrates partners from Austria, France

  6. Principle and geometric precision of photographic geological logging of tunnels

    NASA Astrophysics Data System (ADS)

    Li, Hao; Zhang, Rong-Chun; Yang, Biao; Wu, Ming-Fei

    2014-01-01

    Considering the problem of engineering geological logging technique by means of sketching at the work site, this paper presents a photographic geological logging technique based on photogrammetry as well as engineering geology. The principles, methods, and working process have been discussed, and the photographic geological logging precision of a tunnel and its estimation method have been researched. The theoretical and experimental analysis shows that the precision of the digital unfolded image map of tunnel automatically generated by the photographic geological logging method is sufficient for serving as the logging base map. Besides, the measurement precision of unfolded images or stereopairs meets the requirements of geological attitude measurement. The new technique of photographic geological logging proposed in this paper is expected to replace the current sketch way of engineering geological logging on site, with the operation mode converted from manual operation to computer-aided operation and informatized management.

  7. Geologic Observations and Numerical Modeling: A Combined Approach to Understanding Crater and Basin Formation and Structure

    NASA Astrophysics Data System (ADS)

    Potter, R. W. K.; Head, J. W., III

    2014-12-01

    Impact cratering is a fundamental geological process throughout the Solar System. The Moon is an ideal location to document the impact cratering process due to the number and excellent state of preservation of large craters and basins, and the wide range of geological, geophysical, topographic, mineralogic, remote sensing and returned sample data. Despite the number and excellent preservation state of many large complex craters and basins, their formation and the origin of their structural features and the stages in their evolution remain contentious. To more comprehensively document the final stage of lunar impact basin formation, we have compiled detailed topographic, geological and mineralogic maps of several type examples of peak-ring and multi-ring basins, including the Orientale basin. These data include the mineralogic characteristics of basin ring structures and assist in the interpretation of the target stratigraphy, and the depth of origin of basin rings. Data for the current structure of basins is compared to numerical model outputs of basin-forming impacts, which track formation to the conclusion of dynamic processes (2 to 3 hours after impact). We use the Orientale basin as an example and provide combined correlations and interpretations that assign rings to various stages in the numerical models, and compare these candidates to crustal stratigraphy, with the ultimate aim of producing a consistent model for large crater/basin formation. The shock physics code iSALE is used to numerically model the basin-scale impacts. Constitutive equations and equations of state for materials analogous to the lunar crust (gabbroic anorthosite) and mantle (dunite) are used. Aspects of the numerically-produced lunar basins (e.g., material distribution and accumulated stress) are compared and contrasted to remote observations and geological maps of the Orientale rings and geological units, including ejecta and impact melt deposits.

  8. Current status and future perspectives of electron interactions with molecules, clusters, surfaces, and interfaces [Workshop on Fundamental challenges in electron-driven chemistry; Workshop on Electron-driven processes: Scientific challenges and technological opportunities

    SciTech Connect

    Becker, Kurt H.; McCurdy, C. William; Orlando, Thomas M.; Rescigno, Thomas N.

    2000-09-01

    This report is based largely on presentations and discussions at two workshops and contributions from workshop participants. The workshop on Fundamental Challenges in Electron-Driven Chemistry was held in Berkeley, October 9-10, 1998, and addressed questions regarding theory, computation, and simulation. The workshop on Electron-Driven Processes: Scientific Challenges and Technological Opportunities was held at Stevens Institute of Technology, March 16-17, 2000, and focused largely on experiments. Electron-molecule and electron-atom collisions initiate and drive almost all the relevant chemical processes associated with radiation chemistry, environmental chemistry, stability of waste repositories, plasma-enhanced chemical vapor deposition, plasma processing of materials for microelectronic devices and other applications, and novel light sources for research purposes (e.g. excimer lamps in the extreme ultraviolet) and in everyday lighting applications. The life sciences are a rapidly advancing field where the important role of electron-driven processes is only now beginning to be recognized. Many of the applications of electron-initiated chemical processes require results in the near term. A large-scale, multidisciplinary and collaborative effort should be mounted to solve these problems in a timely way so that their solution will have the needed impact on the urgent questions of understanding the physico-chemical processes initiated and driven by electron interactions.

  9. Geology Before Pluto: Pre-encounter Considerations

    NASA Technical Reports Server (NTRS)

    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 in the form of tectonics and cryo-volcanism.

  10. Geology Before Pluto: Pre-encounter Considerations

    NASA Astrophysics Data System (ADS)

    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 prospects for endogenic activity in the form of tectonics and cryovolcanism.

  11. Making a Geologic Cross Section Name _____________________________ Geology 100 Harbor Section

    E-print Network

    Harbor, David

    of cross section A for help) 2. What symbols represent these formations and in what geologic time periodsp. 1 Making a Geologic Cross Section Name _____________________________ Geology 100 Ā­ Harbor Section Your task is to complete a cross section of geologic structures from a geologic map. Please do

  12. Monte Carlo fundamentals

    SciTech Connect

    Brown, F.B.; Sutton, T.M.

    1996-02-01

    This report is composed of the lecture notes from the first half of a 32-hour graduate-level course on Monte Carlo methods offered at KAPL. These notes, prepared by two of the principle developers of KAPL`s RACER Monte Carlo code, cover the fundamental theory, concepts, and practices for Monte Carlo analysis. In particular, a thorough grounding in the basic fundamentals of Monte Carlo methods is presented, including random number generation, random sampling, the Monte Carlo approach to solving transport problems, computational geometry, collision physics, tallies, and eigenvalue calculations. Furthermore, modern computational algorithms for vector and parallel approaches to Monte Carlo calculations are covered in detail, including fundamental parallel and vector concepts, the event-based algorithm, master/slave schemes, parallel scaling laws, and portability issues.

  13. Geologic Time: Online Edition

    NSDL National Science Digital Library

    1997-10-09

    Offered by the United States Geological Survey (USGS) as a general interest publication, this site is an online edition of a text by the same name, offering a concise overview of the concepts associated with the age of the Earth. The online edition was revised in October of 1997 to reflect current thinking on this topic. Section headers are Geologic Time, Relative Time Scale, Major Divisions of Geologic Time, Index Fossils, Radiometric Time Scale, and Age of the Earth.

  14. The Geology of Virginia

    NSDL National Science Digital Library

    From the College of William of Mary Department of Geology comes the Geology of Virginia Web site. From the Appalachian Plateau to the coastal plain, visitors can explore the geology and physical characteristics of the diverse landscape of the commonwealth of Virginia through simple descriptions and well designed graphics. Even if you don't live in the area, the site does a good job of capturing the interest of anyone looking for quality material on the presented subjects.

  15. Sedimentology and petroleum geology

    SciTech Connect

    Bjorlykke, K.O. (Oslo Univ. (Norway))

    1989-01-01

    This book presents an introduction to sedimentology as well as petroleum geology. It integrates both subjects, which are closely related but mostly treated separately. The author covers the basic aspects of sedimentology, sedimentary geochemistry and diagenesis. Principles of stratigraphy, seismic stratigraphy and basin modelling forms the base for the part on petroleum geology. Subjects discussed include the composition of kerogen and hydrocarbons, theories of migration and trapping of hydrocarbons and properties of reservoir rocks. Introductions to well logging and production geology are given.

  16. A program for mass spectrometer control and data processing analyses in isotope geology; written in BASIC for an 8K Nova 1120 computer

    USGS Publications Warehouse

    Stacey, J.S.; Hope, J.

    1975-01-01

    A system is described which uses a minicomputer to control a surface ionization mass spectrometer in the peak switching mode, with the object of computing isotopic abundance ratios of elements of geologic interest. The program uses the BASIC language and is sufficiently flexible to be used for multiblock analyses of any spectrum containing from two to five peaks. In the case of strontium analyses, ratios are corrected for rubidium content and normalized for mass spectrometer fractionation. Although almost any minicomputer would be suitable, the model used was the Data General Nova 1210 with 8K memory. Assembly language driver program and interface hardware-descriptions for the Nova 1210 are included.

  17. Reports of Planetary Geology Program, 1981

    NASA Technical Reports Server (NTRS)

    Holt, H. E. (compiler)

    1981-01-01

    Abstracts of 205 reports from Principal investigators of NASA's Planetary Geology Program succinctly summarize work conducted and reflect the significant accomplishments. The entries are arranged under the following topics: (1) Saturnian satellites; (2) asteroids, comets and Galilean satellites; (3) cratering processes and landform development; (4) volcanic processes and landforms; (5) Aerolian processes and landforms; (6) fluvial, preglacial, and other processes of landform development; (7) Mars polar deposits, volatiles, and climate; (8) structure, tectonics, and stratigraphy; (9) remote sensing and regolith chemistry; (10) cartography and geologic mapping; and (11) special programs.

  18. Fundamentals of fluid sealing

    NASA Technical Reports Server (NTRS)

    Zuk, J.

    1976-01-01

    The fundamentals of fluid sealing, including seal operating regimes, are discussed and the general fluid-flow equations for fluid sealing are developed. Seal performance parameters such as leakage and power loss are presented. Included in the discussion are the effects of geometry, surface deformations, rotation, and both laminar and turbulent flows. The concept of pressure balancing is presented, as are differences between liquid and gas sealing. Mechanisms of seal surface separation, fundamental friction and wear concepts applicable to seals, seal materials, and pressure-velocity (PV) criteria are discussed.

  19. Understanding Geologic Maps

    NSDL National Science Digital Library

    Cara Burberry

    This is an exercise in which students are reintroduced to geologic maps and encouraged to "deconstruct" the map into constituent elements in order to understand the geologic history of the area. The preceding lectures in the course have recapitulated material that the students have covered in Introduction to Physical Geology. During class, the students work through the maps that were part of lab exercises in the Intro level course, so that basic concepts are recalled (superposition, cross-cutting relationships, basic faults and folds). The final product is a geologic history of this map area.

  20. Geologic Mapping Exercise

    NSDL National Science Digital Library

    Andrew Smith

    This exercise is designed to simulate how a basic geological investigation of a site takes place. A basic geological investigation includes familiarizing yourself with the unconsolidated sediments, rocks, structural geology, and groundwater present at your site. As part of this exercise you will have to properly identify a variety of rock types and sediments, create maps that represent data you collected at each location, and complete a basic report of your findings (optional). Once completed, this exercise should give students a basic understanding of how the various concepts used throughout the semester are applied in the real world in the form of a geological investigation.

  1. Dione's spectral and geological properties

    USGS Publications Warehouse

    Stephan, K.; Jaumann, R.; Wagner, R.; Clark, R.N.; Cruikshank, D.P.; Hibbitts, C.A.; Roatsch, T.; Hoffmann, H.; Brown, R.H.; Filiacchione, G.; Buratti, B.J.; Hansen, G.B.; McCord, T.B.; Nicholson, P.D.; Baines, K.H.

    2010-01-01

    We present a detailed analysis of the variations in spectral properties across the surface of Saturn's satellite Dione using Cassini/VIMS data and their relationships to geological and/or morphological characteristics as seen in the Cassini/ISS images. This analysis focuses on a local region on Dione's anti-saturnian hemisphere that was observed by VIMS with high spatial resolution during orbit 16 in October 2005. The results are incorporated into a global context provided by VIMS data acquired within Cassini's first 50 orbits. Our results show that Dione's surface is dominated by at least one global process. Bombardment by magnetospheric particles is consistent with the concentration of dark material and enhanced CO2 absorption on the trailing hemisphere of Dione independent of the geology. Local regions within this terrain indicate a special kind of resurfacing that probably is related to large-scale impact process. In contrast, the enhanced ice signature on the leading side is associated with the extended ejecta of the fresh impact crater Creusa (???49??N/76??W). Although no geologically active regions could be identified, Dione's tectonized regions observed with high spatial resolution partly show some clean H2O ice implying that tectonic processes could have continued into more recent times. ?? 2009 Elsevier Inc. All rights reserved.

  2. Fundamental Materials Research and Advanced Process Development for Thin-Film CIS-Based Photovoltaics: Final Technical Report, 2 October 2001 - 30 September 2005

    SciTech Connect

    Anderson, T. J.; Li, S. S.; Crisalle, O. D.; Craciun, V.

    2006-09-01

    The objectives for this thin-film copper-indium-diselenide (CIS) solar cell project cover the following areas: Develop and characterize buffer layers for CIS-based solar cell; grow and characterize chemical-bath deposition of Znx Cd1-xS buffer layers grown on CIGS absorbers; study effects of buffer-layer processing on CIGS thin films characterized by the dual-beam optical modulation technique; grow epitaxial CuInSe2 at high temperature; study the defect structure of CGS by photoluminescence spectroscopy; investigate deep-level defects in Cu(In,Ga)Se2 solar cells by deep-level transient spectroscopy; conduct thermodynamic modeling of the isothermal 500 C section of the Cu-In-Se system using a defect model; form alpha-CuInSe2 by rapid thermal processing of a stacked binary compound bilayer; investigate pulsed non-melt laser annealing on the film properties and performance of Cu(In,Ga)Se2 solar cells; and conduct device modeling and simulation of CIGS solar cells.

  3. Fundamental study of the NOXSO combined NO/sub x//SO/sub 2/ flue gas treatment process: corrosion and its prevention

    SciTech Connect

    Perng, T.P.

    1984-07-31

    The high temperature corrosion behavior (oxidation, sulfidation, and hot corrosion) of a number of Ni-base and Fe-base alloys has been discussed. Ni-base alloys are found to be incompatible with the compounds involved in the NOXSO Process regeneration reactions. Austenitic stainless steels are susceptible to sensitization and to a limited extent, hot corrosion. Type 446 ferritic stainless steel with high Cr content and no Ni performs satisfactorily under the service conditions. Improvement of high temperature corrosion resistance can be achieved by surface coatings such as aluminizing, chromizing, MCrAlY overlay coatings, or ceramic coatings. Aluminized 316L stainless steel has proven effective against the corrosion attack. Other base materials such as low alloy steels, low Cr-content ferritic stainless steels, or low carbon austenitic stainless steels may also be considered, provided good surface coatings are applied. 11 references, 8 figures, 9 tables.

  4. Fundamentals of Diesel Engines.

    ERIC Educational Resources Information Center

    Marine Corps Inst., Washington, DC.

    This student guide, one of a series of correspondence training courses designed to improve the job performance of members of the Marine Corps, deals with the fundamentals of diesel engine mechanics. Addressed in the three individual units of the course are the following topics: basic principles of diesel mechanics; principles, mechanics, and…

  5. The Fundamental Property Relation.

    ERIC Educational Resources Information Center

    Martin, Joseph J.

    1983-01-01

    Discusses a basic equation in thermodynamics (the fundamental property relation), focusing on a logical approach to the development of the relation where effects other than thermal, compression, and exchange of matter with the surroundings are considered. Also demonstrates erroneous treatments of the relation in three well-known textbooks. (JN)

  6. Fundamentals of soil science

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study guide provides comments and references for professional soil scientists who are studying for the soil science fundamentals exam needed as the first step for certification. The performance objectives were determined by the Soil Science Society of America's Council of Soil Science Examiners...

  7. Oracle Developer Oracle Fundamentals

    E-print Network

    Alabama in Huntsville, University of

    Oracle Developer Oracle Fundamentals 21 hours, $945 Developers and database administrators gain a thorough grounding in technologies and concepts that form the foundation of the Oracle Database Server. Novice or experienced users come to fully understand the many facets of Oracle enabling them to handle

  8. Laser Fundamentals and Experiments.

    ERIC Educational Resources Information Center

    Van Pelt, W. F.; And Others

    As a result of work performed at the Southwestern Radiological Health Laboratory with respect to lasers, this manual was prepared in response to the increasing use of lasers in high schools and colleges. It is directed primarily toward the high school instructor who may use the text for a short course in laser fundamentals. The definition of the…

  9. DSMBs: Foundations and Fundamentals

    E-print Network

    Nguyen, Danh

    DSMBs: Foundations and Fundamentals Frederick W. Luthardt, M.A., M.A. Manager, Compliance for efficacy and risks · Overall regulatory compliance, Data QC Overall Project compliance #12;Research Ethics throughout industry sponsored trials · Foundations (e.g., Cystic Fibrosis Foundation) · FDA guidance on DMCs

  10. Fundamentals of solar cells

    Microsoft Academic Search

    A. L. Farhenbruch; R. H. Bube

    1983-01-01

    This text is addressed to upper level graduate students with background in solid state physics and to scientists and engineers involved in solar cell research. The author aims to present fundamental physical principles rather than the state-of-the-art. Specific devices are used to illustrate basic phenomena and to indicate possibilities for innovative design. Contents, abridged: Solar insolation. The calculation of solar

  11. Fundamentals of Geophysics

    Microsoft Academic Search

    William Lowrie; Ola M. Saether; A. A. Balkema; GEO ENV; Ian Lerche; M. C. R. Davies; M. Armstrong

    1997-01-01

    This unique textbook presents a comprehensive overview of the fundamental principles of geophysics. Unlike most geophysics textbooks, it combines both the applied and theoretical aspects to the subject. The author explains complex geophysical concepts using abundant diagrams, a simplified mathematical treatment, and easy-to-follow equations. After placing the Earth in the context of the solar system, he describes each major branch

  12. DNA Topology: Fundamentals

    E-print Network

    Mirkin, Sergei

    DNA Topology: Fundamentals Sergei M Mirkin, University of Illinois at Chicago, Illinois, USA Topological characteristics of DNA and specifically DNA supercoiling influence all major DNA transactions in living cells. DNA supercoiling induces the formation of unusual secondary structure by specific DNA

  13. Homeschooling and Religious Fundamentalism

    ERIC Educational Resources Information Center

    Kunzman, Robert

    2010-01-01

    This article considers the relationship between homeschooling and religious fundamentalism by focusing on their intersection in the philosophies and practices of conservative Christian homeschoolers in the United States. Homeschooling provides an ideal educational setting to support several core fundamentalist principles: resistance to…

  14. Fundamentals of Private Pensions

    Microsoft Academic Search

    Dan M. McGill; Kyle N. Brown; John J. Haley; Sylvester J. Schieber; Mark J. Warshawsky

    1996-01-01

    For almost five decades, Fundamentals of Private Pensions has been the most authoritative text and reference book on private pensions in the US in the world. The revised and updated eighth edition adds to past knowledge while providing exciting new perspectives on the provision of retirement income. This new edition is organized into six main sections dealing with a variety

  15. Food Service Fundamentals.

    ERIC Educational Resources Information Center

    Marine Corps Inst., Washington, DC.

    Developed as part of the Marine Corps Institute (MCI) correspondence training program, this course on food service fundamentals is designed to provide a general background in the basic aspects of the food service program in the Marine Corps; it is adaptable for nonmilitary instruction. Introductory materials include specific information for MCI…

  16. Blending geological observations and convection models to reconstruct mantle dynamics

    NASA Astrophysics Data System (ADS)

    Coltice, Nicolas; Bocher, Marie; Fournier, Alexandre; Tackley, Paul

    2015-04-01

    Knowledge of the state of the Earth mantle and its temporal evolution is fundamental to a variety of disciplines in Earth Sciences, from the internal dynamics to its many expressions in the geological record (postglacial rebound, sea level change, ore deposit, tectonics or geomagnetic reversals). Mantle convection theory is the centerpiece to unravel the present and past state of the mantle. For the past 40 years considerable efforts have been made to improve the quality of numerical models of mantle convection. However, they are still sparsely used to estimate the convective history of the solid Earth, in comparison to ocean or atmospheric models for weather and climate prediction. The main shortcoming is their inability to successfully produce Earth-like seafloor spreading and continental drift self-consistently. Recent convection models have begun to successfully predict these processes. Such breakthrough opens the opportunity to retrieve the recent dynamics of the Earth's mantle by blending convection models together with advanced geological datasets. A proof of concept will be presented, consisting in a synthetic test based on a sequential data assimilation methodology.

  17. Atomic-Scale Theoretical Studies of Fundamental Properties and Processes in CHNO Plastic-Bonded Explosive Constituent Materials under Static and Dynamic Compression

    NASA Astrophysics Data System (ADS)

    Sewell, Thomas

    2013-06-01

    The results of recent theoretical atomic-scale studies of CHNO plastic-bonded explosive constituent materials will be presented, emphasizing the effects of static and dynamic compression on structure, vibrational spectroscopy, energy redistribution, and dynamic deformation processes. Among the chemical compounds to be discussed are pentaerythritol tetranitrate (PETN), hexahydro-1,3,5-trinitro-1,3,5-s-triazine (RDX), nitromethane, and hydroxyl-terminated polybutadiene (HTPB). Specific topics to be discussed include pressure-dependent terahertz IR absorption spectra in crystalline PETN and RDX, microscopic material flow characteristics and energy localization during and after pore collapse in shocked (100)-oriented RDX, establishment of local thermodynamic temperature and the approach to thermal equilibrium in shocked (100)-oriented nitromethane, and structural changes and relaxation phenomena that occur in shocked amorphous cis-HTPB. In the case of shocked HTPB, comparisons will be made between results obtained using fully-atomic and coarse-grained (united atom) molecular dynamics force field models. Rather than attempting to discuss any given topic in extended detail, 3-4 vignettes will be presented that highlight outstanding scientific questions and the predictive methods and tools we are developing to answer them. The results of recent theoretical atomic-scale studies of CHNO plastic-bonded explosive constituent materials will be presented, emphasizing the effects of static and dynamic compression on structure, vibrational spectroscopy, energy redistribution, and dynamic deformation processes. Among the chemical compounds to be discussed are pentaerythritol tetranitrate (PETN), hexahydro-1,3,5-trinitro-1,3,5-s-triazine (RDX), nitromethane, and hydroxyl-terminated polybutadiene (HTPB). Specific topics to be discussed include pressure-dependent terahertz IR absorption spectra in crystalline PETN and RDX, microscopic material flow characteristics and energy localization during and after pore collapse in shocked (100)-oriented RDX, establishment of local thermodynamic temperature and the approach to thermal equilibrium in shocked (100)-oriented nitromethane, and structural changes and relaxation phenomena that occur in shocked amorphous cis-HTPB. In the case of shocked HTPB, comparisons will be made between results obtained using fully-atomic and coarse-grained (united atom) molecular dynamics force field models. Rather than attempting to discuss any given topic in extended detail, 3-4 vignettes will be presented that highlight outstanding scientific questions and the predictive methods and tools we are developing to answer them. The U.S. Defense Threat Reduction Agency and Office of Naval Research supported this research.

  18. Advances in planetary geology

    NASA Technical Reports Server (NTRS)

    Woronow, A. (editor)

    1981-01-01

    This second issue in a new series intended to serve the planetary geology community with a form for quick and thorough communications includes (1) a catalog of terrestrial craterform structures for northern Europe; (2) abstracts of results of the Planetary Geology Program, and (3) a list of the photographic holdings of regional planetary image facilities.

  19. Petroleum geology of Tunisia

    Microsoft Academic Search

    P. F. Burollet; A. B. Ferjami; F. Mejri

    1990-01-01

    Recent discoveries and important oil shows have proven the existence of hydrocarbons in newly identified depocenters and reservoirs. In general, except for some areas around the producing fields, Tunisia is largely underdrilled. The national company ETAP has decided to release data and to publish a synthesis on the petroleum geology of Tunisia. The geology of Tunisia provides a fine example

  20. External Resource: Geologic Time

    NSDL National Science Digital Library

    1900-01-01

    This NASA sponsored webpage, Center for Educational Technologies, teaches students about Geologic Time. The age of Earth is so long compared to all periods of time that we humans are familiar with, it has been given a special name: Geologic time. The age

  1. Geologic time scale bookmark

    USGS Publications Warehouse

    U.S. Geological Survey

    2012-01-01

    This bookmark, designed for use with U.S. Geological Survey activities at the 2nd USA Science and Engineering Festival (April 26–29, 2012), is adapted from the more detailed Fact Sheet 2010–3059 "Divisions of Geologic Time." The information that it presents is widely sought by educators and students.

  2. National Geologic Map Database

    NSDL National Science Digital Library

    1997-01-01

    The National Geologic Map Database (NGMDB) is an Internet-based system for query and retrieval of earth-science map information, created as a collaborative effort between the USGS and the Association of American State Geologists. Its functions include providing a catalog of available map information; a data repository; and a source for general information on the nature and intended uses of the various types of earth-science information. The map catalog is a comprehensive, searchable catalog of all geoscience maps of the United States, in paper or digital format. It includes maps published in geological survey formal series and open-file series, maps in books, theses and dissertations, maps published by park associations, scientific societies, and other agencies, as well as publications that do not contain a map but instead provide a geological description of an area (for example, a state park). The geologic-names lexicon (GEOLEX) is a search tool for lithologic and geochronologic unit names. It now contains roughly 90% of the geologic names found in the most recent listing of USGS-approved geologic names. Current mapping activities at 1:24,000- and 1:100,000-scale are listed in the Geologic Mapping in Progress Database. Information on how to find topographic maps and list of geology-related links is also available.

  3. Geology of the Caribbean.

    ERIC Educational Resources Information Center

    Dillon, William P.; And Others

    1988-01-01

    Describes some of the geologic characteristics of the Caribbean region. Discusses the use of some new techniques, including broad-range swath imaging of the sea floor that produces photograph-like images, and satellite measurement of crustal movements, which may help to explain the complex geology of the region. (TW)

  4. Geology of Caves

    NSDL National Science Digital Library

    This webpage of the United States Geological Survey (USGS) and National Park Service (NPS) describes the geology and features of caves. It discusses cave formation, features, minerals found in caves, uses of caves, and various investigations of caves. There is an educational activity on karst topography formation, and links for additional information.

  5. California Geological Survey - Landslides

    NSDL National Science Digital Library

    California Geological Survey

    This page from the CA Geological Survey (CGS) presents information on landslides as well as maps and products of various past and present CGS programs to map and respond to landslides in the state of California, including the Forest and Watershed Geology Program, the Seismic Hazards Zonation Program, the Caltrans Highway Corridor Mapping project, and the Landslide Map Index.

  6. Advances in Planetary Geology

    NASA Technical Reports Server (NTRS)

    Woronow, A. (editor)

    1982-01-01

    Advances in Planetary Geology is a new series intended to serve the planetary geology community with a form for quick and thorough communications. There are no set lists of acceptable topics or formats, and submitted manuscripts will not undergo a formal review. All submissions should be in a camera ready form, preferably spaced, and submitted to the editor.

  7. Earth Sciences Geology Option

    E-print Network

    Kurapov, Alexander

    Earth Sciences with Geology Option Geological sciences focus on understanding the Earth, from its, mountain building, land surface evolution, and mineral resource creation over the Earth's 4.6 billion-year history. A geologist contributes to society through the discovery of earth resources, such as metals

  8. Earthquakes and Geology

    NSDL National Science Digital Library

    David Ozsvath

    In this activity, students investigate the relationship between intensity of ground motion and type of rock or alluvium, as seen in the 1994 Northridge, California earthquake. They will examine a map of Mercalli intensity, a cross-section showing geologic structures and rock types, and a map of surficial geology, and answer questions pertaining to amplification of ground motion and S-wave velocities.

  9. Glossary of geology

    SciTech Connect

    Bates, R.L.; Jackson, J.A.

    1987-01-01

    This third edition of the Glossary of Geology contains approximately 37,000 terms, or 1,000 more than the second edition. New entries are especially numerous in the fields of carbonate sedimentology, hydrogeology, marine geology, mineralogy, ore deposits, plate tectonics, snow and ice, and stratigraphic nomenclature. Many of the definitions provide background information.

  10. British Geological Survey: Learning

    NSDL National Science Digital Library

    The British Geological Survey (BGS) has a wealth of information about the earth sciences, and they are quite willing to share it with others. This page contains information and resources for anyone interested in geology for educational or leisure purposes, and it is contained with four sections. First up is "Popular geology", which includes "Britain beneath our feet", an interactive atlas of geology, resources, and land quality. This section also contains graphics about climate change and earthquakes. The second section is titled "Educational resources". Here visitors can ask scientists at the BGS specific questions and they can also download several free posters. The third section is called "Educational news and events" and it features upcoming events at the BGS and links to their free magazine, "Earthwise". The site is rounded out by the fourth section titled "From the BGS Archives". Here visitors can view historic geological photographs and also view field sketches and watercolors by Alexander Henry Green, the celebrated Victorian geologist.

  11. Wyoming State Geological Survey

    NSDL National Science Digital Library

    This agency's mission is to study, examine, and seek an understanding of the geology, mineral resources, and physical features of the State; to prepare, publish, and distribute reports and maps of Wyoming's geology, mineral resources, and physical features; and to provide information, advice, and services related to the geology, mineral resources, and physical features of the State. This site contains details and reports about metals in Wyoming, earthquakes and other hazards, coal, industrial minerals, uranium, oil and gas. The field trip section contains details about various areas to visit with students and gives a general geologic description. There is also a searchable bibliography with publications about Wyoming geology. Links are provided for additional resources.

  12. Virtual Tour of Maine Geology

    NSDL National Science Digital Library

    This selection of slide shows provides a photographic tour of Maine geology. Users can choose slide shows on surficial, bedrock, and coastal geology; fossils, geologic hazards, groundwater and wells; or mineral collecting, mining, and quarrying.

  13. Essential Elements of Geologic Reports.

    ERIC Educational Resources Information Center

    Webb, Elmer James

    1988-01-01

    Described is a report outline for geologic reports. Essential elements include title; abstract; introduction; stratigraphy; petrography; geochemistry; petrology; geophysics; structural geology; geologic history; modeling; economics; conclusions; and recommendations. (Author/CW)

  14. Roadside Geology of Yosemite Valley

    NSDL National Science Digital Library

    A virtual geology field trip to Yosemite Valley. Includes a geologic map of Yosemite, numerous large pictures of the area and discussion of geological events and natural disasters which have occurred in Yosemite.

  15. A Fundamental Approach to Resin Cure Kinetics

    Microsoft Academic Search

    Leroy Chiao; Richard E. Lyon

    1990-01-01

    Thermoset polymer resins are an important class of materials, particularly when used as the matrix for advanced fiber composites. Because material performance is directly related to processing, it is useful to study the cure kinetics of these resins for use in process modeling, design and control. Several workers have attacked this problem using empirical rate laws. However, a fundamental approach

  16. Geologic studies: Executive summary report

    SciTech Connect

    Popenoe, P.

    1994-01-01

    The general objectives of the geological oceanography program in 1976-1977 were to (1) measure the rate, direction, and forcing mechanisms of sediment mobility over the sea bed, and to monitor resultant changes in bottom morphology or texture; (2) determine the concentration, distribution, and flux of suspended particulate matter in the water column; (3) determine the vertical distribution of trace metals in the near-surface sediment at selected locations; (4) evaluate potential geological hazards to oil and gas development due to surficial and intermediate depth structure and mass sediment transport events; (5) identify and evaluate the distribution and significance of outcrop and reefal structures; and (6) support the activities of the chemical/biological contractor by obtaining information on sediment texture and composition, particularly as it relates to the physical, biological, and chemical processes of the shelf. The report presents a summation of principal findings and conclusions from this initial effort.

  17. Fundamental Superstrings as Holograms

    E-print Network

    Atish Dabholkar; Sameer Murthy

    2007-09-07

    The worldsheet of a macroscopic fundamental superstring in the Green-Schwarz light-cone gauge is viewed as a possible boundary hologram of the near horizon region of a small black string. For toroidally compactified strings, the hologram has global symmetries of AdS_3 \\times S^{d-1} \\times T^{8-d}, (d =3,..,8), only some of which extend to local conformal symmetries. We construct the bulk string theory in detail for the particular case of d=3. The symmetries of the hologram are correctly reproduced from this exact worldsheet description in the bulk. Moreover, the central charge of the boundary Virasoro algebra obtained from the bulk agrees with the Wald entropy of the associated small black holes. This construction provides an exact CFT description of the near horizon region of small black holes both in Type-II and heterotic string theory arising from multiply wound fundamental superstrings.

  18. Fundamental Superstrings as Holograms

    E-print Network

    Dabholkar, Atish

    2008-01-01

    The worldsheet of a macroscopic fundamental superstring in the Green-Schwarz light-cone gauge is viewed as a possible boundary hologram of the near horizon region of a small black string. For toroidally compactified strings, the hologram has global symmetries of AdS_3 \\times S^{d-1} \\times T^{8-d}, (d =3,..,8), only some of which extend to local conformal symmetries. We construct the bulk string theory in detail for the particular case of d=3. The symmetries of the hologram are correctly reproduced from this exact worldsheet description in the bulk. Moreover, the central charge of the boundary Virasoro algebra obtained from the bulk agrees with the Wald entropy of the associated small black holes. This construction provides an exact CFT description of the near horizon region of small black holes both in Type-II and heterotic string theory arising from multiply wound fundamental superstrings.

  19. Fundamental Theorem of Calculus

    E-print Network

    Sobczyk, Garret

    2008-01-01

    A simple but rigorous proof of the Fundamental Theorem of Calculus is given in geometric calculus, after the basis for this theory in geometric algebra has been explained. Various classical examples of this theorem, such as the Green's and Stokes' theorem are discussed, as well as the new theory of monogenic functions, which generalizes the concept of an analytic function of a complex variable to higher dimensions.

  20. Fundamental studies in geodynamics

    NASA Technical Reports Server (NTRS)

    Anderson, D. L.; Hager, B. H.; Kanamori, H.

    1981-01-01

    Research in fundamental studies in geodynamics continued in a number of fields including seismic observations and analysis, synthesis of geochemical data, theoretical investigation of geoid anomalies, extensive numerical experiments in a number of geodynamical contexts, and a new field seismic volcanology. Summaries of work in progress or completed during this report period are given. Abstracts of publications submitted from work in progress during this report period are attached as an appendix.

  1. Digital Fundamentals: Course Materials

    NSDL National Science Digital Library

    This course provided by eSyst describes digital fundamentals. An introduction explains the traditional view and systems view of this topic. The course includes numerous instructor presentations and student guides. Topics for these include serial digital interfaces, circuit boards, and microprocessors. A detailed course outline, student learning outcomes, and links to additional online resources are also provided. Users must create a free, quick login in order to download the materials.

  2. Testing Fundamental Loads

    NSDL National Science Digital Library

    2014-09-18

    Students conduct several simple lab activities to learn about the five fundamental load types that can act on structures: tension, compression, shear, bending, and torsion. To learn the telltale marks of failure caused by these load types, they break foam insulation blocks by applying these five load types, carefully examine each type of fracture pattern (break in the material) and make drawings of the fracture patterns.

  3. Fundamentals of Radio Telescopes

    Microsoft Academic Search

    Jingquan Cheng

    \\u000a In this chapter, a brief review of radio astronomical telescopes is provided. The fundamental concepts of radio antennas,\\u000a including radiation pattern, antenna gain, antenna temperature, antenna efficiency, and polarization, are introduced. These\\u000a concepts are important for readers outside the radio antenna field. The emphasis of this chapter is placed on the parameter\\u000a design of reflector radio telescope antennas. These parameter

  4. Redefining the Fundamental Questions

    ERIC Educational Resources Information Center

    Crain, Margaret Ann

    2006-01-01

    Every researcher must make some fundamental questions. A researcher's questions should include the following: (1) What is the nature of the reality that I wish to study? (2) How will I know it? (3) What must I do to know it? (4) Who am I? (5) Where is God in this? and (6) For religious educators--How does my research lead to a world of peace and…

  5. Fundamental enabling issues in nanotechnology :

    SciTech Connect

    Floro, Jerrold Anthony; Foiles, Stephen Martin; Hearne, Sean Joseph; Hoyt, Jeffrey John; Seel, Steven Craig; Webb, Edmund Blackburn,; Morales, Alfredo Martin; Zimmerman, Jonathan A.

    2007-10-01

    To effectively integrate nanotechnology into functional devices, fundamental aspects of material behavior at the nanometer scale must be understood. Stresses generated during thin film growth strongly influence component lifetime and performance; stress has also been proposed as a mechanism for stabilizing supported nanoscale structures. Yet the intrinsic connections between the evolving morphology of supported nanostructures and stress generation are still a matter of debate. This report presents results from a combined experiment and modeling approach to study stress evolution during thin film growth. Fully atomistic simulations are presented predicting stress generation mechanisms and magnitudes during all growth stages, from island nucleation to coalescence and film thickening. Simulations are validated by electrodeposition growth experiments, which establish the dependence of microstructure and growth stresses on process conditions and deposition geometry. Sandia is one of the few facilities with the resources to combine experiments and modeling/theory in this close a fashion. Experiments predicted an ongoing coalescence process that generates signficant tensile stress. Data from deposition experiments also supports the existence of a kinetically limited compressive stress generation mechanism. Atomistic simulations explored island coalescence and deposition onto surfaces intersected by grain boundary structures to permit investigation of stress evolution during later growth stages, e.g. continual island coalescence and adatom incorporation into grain boundaries. The predictive capabilities of simulation permit direct determination of fundamental processes active in stress generation at the nanometer scale while connecting those processes, via new theory, to continuum models for much larger island and film structures. Our combined experiment and simulation results reveal the necessary materials science to tailor stress, and therefore performance, in nanostructures and, eventually, integrated nanocomponents.

  6. Natural Analogs for Geologic Storage of CO2: An Integrated Global Research Program

    Microsoft Academic Search

    A. A. J. Rigg

    Coordinated research efforts are underway on three continents (North America, Europe, Australia) to study naturally occurring carbon dioxide deposits, in order to address fundamental questions and concerns about the long-term storage of CO2 in geologic formations. Natural accumulations of carbon dioxide exist in many geologic basins. Some deposits are stored in secure and impermeable traps, whereas others are unstable and

  7. Geological research for public outreach and education in Lithuania

    NASA Astrophysics Data System (ADS)

    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 exposition at the Museum of Erratic Boulders in NW Lithuania is being rearranged for educational purposes, to show the major rock types and their origins more clearly. A new exhibition is supplemented with computer portals presenting geological processes, geological quizzes, animations etc. Magmatism, metamorphism, sedimentation and other geological processes are demonstrated using erratic boulders brought by glaciers from Scandinavia and northern Russia. A part of the exhibition is devoted to glaciation processes and arrival of ice sheets to Lithuania. Visitors are able to examine large erratic boulder groups in a surrounding park and to enjoy beautiful environment. The exhibition also demonstrates mineral resources of Lithuania, different fossils and stones from a human body. In all cases it was recognised that a lack of geological information limits the use of geology for public outreach. Ongoing scientific research is essential in many places as well as a mediator's job for interpreting the results of highly specialised research results and to adapt them for public consumption.

  8. Formation evaluation: Geological procedures

    SciTech Connect

    Whittaker, A.

    1985-01-01

    This volume goes beyond a discussion of petroleum geology and the techniques of hydrocarbon (oil and gas) logging as a reservoir evaluation tool. It provides the logging geologist with a review of geological techniques and classification systems that will ensure the maximum development of communicable geological information. Contents include: 1. Introduction--cuttings recovery, cutting sampling, core sampling, rock classification; 2. Detrital rocks--classification, description; 3. Carbonate rocks--classification, description; 4. Chemical rocks-introduction, siliceous rocks, ferruginous rocks, aluminous rocks, phosphatic rocks, aluminous rocks, carbonaceous rocks; 5. Igneous and metamorpbic rocks; Appendix; References and Index.

  9. Journal of Geology

    NSDL National Science Digital Library

    From the University of Chicago Press's Journals Division, the Journal of Geology is currently available online free of charge (note: subscription fees may soon apply, but no initiation date is provided). This first-rate technical journal, which publishes "research and theory in geophysics, geochemistry, sedimentology, geomorphology, petrology, plate tectonics, volcanology, structural geology, mineralogy, and planetary sciences" has been in print form since 1893. All of the 1999 issues of the Journal of Geology electronic edition are available here. Internet users can access full-text articles with internal links to references and figures (html, .pdf. .ps).

  10. Brine flow in heated geologic salt.

    SciTech Connect

    Kuhlman, Kristopher L.; Malama, Bwalya

    2013-03-01

    This report is a summary of the physical processes, primary governing equations, solution approaches, and historic testing related to brine migration in geologic salt. Although most information presented in this report is not new, we synthesize a large amount of material scattered across dozens of laboratory reports, journal papers, conference proceedings, and textbooks. We present a mathematical description of the governing brine flow mechanisms in geologic salt. We outline the general coupled thermal, multi-phase hydrologic, and mechanical processes. We derive these processes' governing equations, which can be used to predict brine flow. These equations are valid under a wide variety of conditions applicable to radioactive waste disposal in rooms and boreholes excavated into geologic salt.

  11. Planetary Geology and Geophysics Program

    NASA Technical Reports Server (NTRS)

    McGill, George E.

    2004-01-01

    Geological mapping and topical studies, primarily in the southern Acidalia Planitia/Cydonia Mensae region of Mars is presented. The overall objective was to understand geologic processes and crustal history in the northern lowland in order to assess the probability that an ocean once existed in this region. The major deliverable is a block of 6 1:500,000 scale geologic maps that will be published in 2004 as a single map at 1:1,000,000 scale along with extensive descriptive and interpretive text. A major issue addressed by the mapping was the relative ages of the extensive plains of Acidalia Planitia and the knobs and mesas of Cydonia Mensae. The mapping results clearly favor a younger age for the plains. Topical studies included a preliminary analysis of the very abundant small domes and cones to assess the possibility that their origins could be determined by detailed mapping and remote-sensing analysis. We also tested the validity of putative shorelines by using GIs to co-register full-resolution MOLA altimetry data and Viking images with these shorelines plotted on them. Of the 3 proposed shorelines in this area, one is probably valid, one is definitely not valid, and the third is apparently 2 shorelines closely spaced in elevation. Publications supported entirely or in part by this grant are included.

  12. Fundamental Limits to Cellular Sensing

    E-print Network

    Pieter Rein ten Wolde; Nils B. Becker; Thomas E. Ouldridge; A. Mugler

    2015-05-25

    In recent years experiments have demonstrated that living cells can measure low chemical concentrations with high precision, and much progress has been made in understanding what sets the fundamental limit to the precision of chemical sensing. Chemical concentration measurements start with the binding of ligand molecules to receptor proteins, which is an inherently noisy process, especially at low concentrations. The signaling networks that transmit the information on the ligand concentration from the receptors into the cell have to filter this noise extrinsic to the cell as much as possible. These networks, however, are also stochastic in nature, which means that they will also add noise to the transmitted signal. In this review, we will first discuss how the diffusive transport and binding of ligand to the receptor sets the receptor correlation time, and then how downstream signaling pathways integrate the noise in the receptor state; we will discuss how the number of receptors, the receptor correlation time, and the effective integration time together set a fundamental limit on the precision of sensing. We then discuss how cells can remove the receptor noise while simultaneously suppressing the intrinsic noise in the signaling network. We describe why this mechanism of time integration requires three classes of resources---receptors and their integration time, readout molecules, energy---and how each resource class sets a fundamental sensing limit. We also briefly discuss the scheme of maximum-likelihood estimation, the role of receptor cooperativity, and how cellular copy protocols differ from canonical copy protocols typically considered in the computational literature, explaining why cellular sensing systems can never reach the Landauer limit on the optimal trade-off between accuracy and energetic cost.

  13. Artificial Intelligence and Nature's Fundamental Process

    Microsoft Academic Search

    Peter Marcer; Peter Rowlands

    In order to address the central question at the heart of the concluding debate at the AAAI 07 Spring quantum interaction symposium, where it was proposed that other probabilistic and nondeterministic theories might replace quantum mechanics, even in relation to quantum physics, and in further explanation of our AAAI Spring 2007 paper 'How Intelligence Evolved?', we outline the derivation from

  14. Fundamental Properties and Processes of Energetic Materials 

    E-print Network

    Ojeda Mota, Oscar Ulises

    2012-10-19

    ............................................................................. 118 Effects of Temperature and Pressure .............................................. 120 VI PECULIAR BEHAVIOUR OF TATB UPON COMPRESSION ....... 127 Structural Changes.... .............................................................................................. 3 1.2 !-HMX unit cell ......................................................................................... 6 1.3 TATB unit cell. ........................................................................................... 10 1...

  15. Weather Observing Fundamentals

    NSDL National Science Digital Library

    COMET

    2014-03-11

    "Weather Observing Fundamentals" provides guidance for U.S. Navy Aerographer's Mates, Quartermasters, and civilian observers tasked with taking and reporting routine, special, and synoptic observations. Although the focus of this lesson is on shipboard observations, much of the content applies to land-based observing and reporting as well. The lesson details standard procedures for taking accurate weather observations and for encoding those observations on COMNAVMETOCCOM Report 3141/3. Exercises throughout the lesson and four weather identification drills at the end provide learners with opportunities to practice and build their skills. The lesson covers a large amount of content. You may wish to work through the material in multiple sessions.

  16. Mastercam Fundamentals Orientation

    NSDL National Science Digital Library

    Kraft, Patrick

    These zipped documents from MatEd provide information on designing a course titled Mastercam Fundamentals Orientation. At the end of the course, students will be able to apply understanding in the use of Mastercam CAD/CAM software to complete wire frame designs, create design of solid models using basic solid model functions, output CNC ā??Gā?¯ code, STL formatted files, and DXF formatted files, and apply knowledge of Mastercam on future projects. The documents include a draft syllabus, contact information for the author of the course, a sample new course proposal form, and a course outline.

  17. Geology and Human Health

    NSDL National Science Digital Library

    The link between geology and human health may not seem obvious, but it many ways geology can affect public health in a variety of crucial ways. Certainly, the relationship between geological factors and water and air quality is one that continues to interest policy makers and others. This site explores these issues, and it was created by the people at Carleton College's Professional Development for Geoscience Faculty initiative. Here visitors can make use of a wide range of educational and supporting materials, including classroom activities, key visualizations, and collections of external links. First-time users may wish to start at the "Resources for Educators" area, which includes a brief overview titled "Essential components of geology and human health" and several helpful posters. The remaining materials can be viewed in sections that include "Bookshelf", "Visualizations", and "Internet Resources".

  18. Devil's Tower Geology

    NSDL National Science Digital Library

    National Park Service (NPS)

    This site from the National Park Service briefly addresses the geology of Devil's Tower. The evolution of various theories on the formation of the tower are discussed. A slide show of the emplacement of the tower is also available.

  19. Bedrock Geology Mapping Exercise

    NSDL National Science Digital Library

    Jim Miller

    This field mapping and map-making exercise is a capstone project for a course on Geological Maps. Over a weekend (~12 hours of field work), students collect lithologic and structural data from outcrops scattered over a one square mile area. Back in the classroom, students digitally compile their field data (outcrop, structure measurements, traverse locations) into ArcMAP. They infer geologic linework (faults and contacts) and units from this data in ArcMAP and then export these data layers into Illustrator. In Illustrator, they add ancillary map components (a cross section, description of map units, correlation diagram, map symbol legend,...) to create a final map at a 1:10,000 scale. Their maps are printed out on 11"x17" paper and saved as a pdf file. This exercise helps the students to appreciate how field data is collected and how these geologic facts are interpretively organized into a four-dimensional picture that is a geologic map.

  20. Experiencing Structural Geology

    ERIC Educational Resources Information Center

    Davis, George H.

    1978-01-01

    Describes an undergraduate structural geology course that incorporates field lab time and research. Lectures, outside readings, and in-class experimentation are coordinated with the field work to prepare a scientific report. (MA)

  1. Stratigraphy and structural geology

    NASA Technical Reports Server (NTRS)

    Carr, M. H.; Wilhelms, D. E.; Greeley, R.; Guest, J. E.

    1976-01-01

    The immediate goal of stratigraphy and structural geology is to reduce the enormous complexity of a planetary surface to comprehensible proportions by dividing the near-surface rocks into units and mapping their distribution and attitude.

  2. Economic Geology and Education

    ERIC Educational Resources Information Center

    Geotimes, 1971

    1971-01-01

    Presents tabulated data of questionnaire responses from 207 colleges. More than 30 groups of data are included relating to various aspects of geology programs including enrollment, student and faculty data and courses. (PR)

  3. External Resource: Geology Jeopardy

    NSDL National Science Digital Library

    1900-01-01

    This interactive Geology Jeopardy game can by used by the individual to review concepts in earth science or in the classroom as a classroom activity. Topics: rocks, minerals, topography, plate tectonics, weathering, erosion, astronomy, meteorology.

  4. North Dakota Geological Survey

    NSDL National Science Digital Library

    This is the homepage of the North Dakota Geological Survey. Site materials include information on the state's oil, gas and coal resources, maps, publications, and regulations. The paleontology page features educational articles, information on fossil collecting, articles about fossil exhibits, and information on the state fossil collection. The state GIS hub creates and distributes digital spatial data that conforms to national mapping standards. The teaching tools page includes illustrations and descriptions of rocks and minerals found in the state, as well as information on meteorites and newsletter articles about teaching North Dakota geology. There are also links to landslide maps, surficial geology maps, and links to other survey publications such as reports, bulletins, field studies, other geological and topographic maps, and information on groundwater resources.

  5. Interactive Geologic Timeline Activity

    NSDL National Science Digital Library

    Environmental Literacy and Inquiry Working Group at Lehigh University

    In this learning activity, students use a web-based geologic timeline to examine temperature, CO2 concentration, and ice cover data to investigate how climate has changed during the last 715 million years.

  6. USGS Geologic Hazards

    NSDL National Science Digital Library

    The Geologic Hazards section of the US Geological Survey (USGS) conducts research into the causes of geological phenomena such as landslides and earthquakes. The homepage connects visitors to the Geologic Hazards team's three main areas of endeavor. Geomagnetism provides links to the National Geomagnetic Information Center; Magnetic Observatories, Models, and Charts; and the Geomagnetic Information Node, which receives geomagnetic observatory data from around the world. The Landslide group studies the "causes and mechanisms of ground failure" to prevent "long-term losses and casualties." Their section provides links to the program and information center, publications, events, and current projects. The Earthquakes department hosts a wealth of information, including neotectonics, engineering seismology, and paleoseismology. Interactive maps are also provided.

  7. Manitoba Geological Survey

    NSDL National Science Digital Library

    This site offers materials on Manitoba geology and minerals, mining and mineral exploration, a Digital Elevation Model of Southern Manitoba (DEMSM) landforms including oblique views, an interactive GIS map gallery of minerals and geology, a study of paleofloods in the Red River Basin including photographs illustrating how scientists delineated the paleofloods, and information on the Manitoba Protected Areas Initiative. Some maps and reports are available to download.

  8. Geologic Time Discussion Analogies

    NSDL National Science Digital Library

    Noah Fay

    The slides provide a fun way of discussing the immensity of geologic time and help to grasp the age of the earth, the time gaps between major geologic events, and the relative minuteness of humans time on earth. After the discussion with the class, students are given opportunity to develop their own analogies using "everyday" things (other than the calendar and money examples used in this activity).

  9. Interpreting Geologic Sections

    NSDL National Science Digital Library

    Paul Morris

    Athro, Limited is a for-profit corporation that publishes high school and college level biology, earth science, and geology course supplements and independent learning materials on the Web. This site provides instruction in interpreting the order of events in three hypothetical and one real geological section. For each section there is a list of events and an animation of the history of the section once the student has decided on the order of events.

  10. Geoscape Vancouver: Living with our Geological Landscape

    NSDL National Science Digital Library

    This site is about the geology and dynamic landscape of the Vancouver, British Columbia area. The people of Vancouver live where the Fraser River breaches the coastal mountains to reach the inland sea of the Strait of Georgia. This landscape is underlain by a variety of earth materials and is continually shaped by earth processes - a geological landscape or geoscape. The processes include colliding crustal plates and mountain-building, earthquakes, volcanic eruptions, landslides, and the work of water, and past glaciers. References are given to printed and web resources for additional information.

  11. Demystifying the Equations of Sedimentary Geology

    NSDL National Science Digital Library

    Larry Lemke

    One of the great challenges in teaching undergraduates is finding ways to get them to apply knowledge or skills learned in one class to problems encountered in subsequent classes. Case in point: the use of algebra, trig, and even rudimentary calculus in geology classes! This activity presents practical ways we can use to build student confidence in their ability to peer into the meaning of the equations they encounter in sedimentary geology. These techniques include: (1) Surgical Strike Reviewsā5 to 10-minute review of relevant math principles at the beginning of the appropriate lecture, (2) Unit Analysesāassigning fundamental units of Mass, Length, and Time to test whether an equation has been derived correctly or to explore the meaning of derivative units of measure that may be unfamiliar to students, and (3) Perturbation Interrogationāasking students to identify whether the quantity of interest described by an equation will increase or decrease when individual components of the equation increase or decrease.

  12. Connecting Soils and Glacial Geology

    NSDL National Science Digital Library

    Holly Dolliver

    The goal of this activity is to provide students an opportunity to connect soil science to surficial geology by using a Soil Surveys. By the end of the activity, students should be able to use a Soil Survey to identify and interpret landforms and surficial features. This activity can be adapted to variety of process (ex. eolian deposits, glacial deposits, bedrock weathering, etc.). County-level soil surveys are available in both paper and online formats for the majority of the United States. Designed for a geomorphology course Has minimal/no quantitative component

  13. Ore metals through geologic history.

    PubMed

    Meyer, C

    1985-03-22

    The ores of chromite, nickel, copper, and zinc show a wide distribution over geologic time, but those of iron, titanium, lead, uranium, gold, silver, molybdenum, tungsten, and tin are more restricted. Many of the limitations to specific time intervals are probably imposed by the evolving tectonic history of Earth interacting with the effects of the biomass on the evolution of the earth's s surface chemistry. Photosynthetic generation of free oxygen and "carbon" contributes significantlly to the diversity of redox potentials in both sedimentary and igneous-related processes of ore formation, influencing the selection of metals at the source, during transport, and at the site of ore deposition. PMID:17777763

  14. Illustrated Glossary of Geologic Terms

    NSDL National Science Digital Library

    Provided by the Geology Department at Iowa State University, this handy illustrated glossary of geological terms is an excellent quick reference resource for students. Continuously upgraded with links to illustrations and text, this geological lexicon is based on the glossary in the textbook Earth: An Introduction to Geological Change by S. Judson and S.M. Richardson. Alphabetical tabs and internal links to related terms let users move quickly around this useful aid for geology students.

  15. The Teacher-Friendly Guide to the Geology of Your Region

    NSDL National Science Digital Library

    2006-08-15

    The guides give teachers the background to make sense of regional and local geology in terms of a basic sequence of historical events and processes. The guides help teachers to meet national and state science standards by providing concrete examples of geologic processes that are closer to home than many classic textbook examples. The guides explain why geological features occur when and where they do in order to help students to remember and predict the nature of local geology.

  16. The Evolution of Dinosaurs Over Geologic Time

    NSDL National Science Digital Library

    This lesson plan asks high school students to combine their knowledge of evolution, geologic time, and dinosaurs into a discussion of how these three topics overlap with regard to dinosaur evolution in the Cretaceous period. Students will read about the work of paleontologist Paul Sereno and list the dinosaurs he has discovered as well as the locations in which they were found and the time periods in which they lived; review the periods of geologic time; review the theory of evolution and write a paragraph explaining how geographic isolation would contribute to the evolutionary process; write paragraphs describing the changes to the continental layout of the Earth during the Cretaceous period; write paragraphs relating geological changes to dinosaur evolution during the Cretaceous period; and create posters or computer presentations illustrating the Earth during the Cretaceous period and the evolution processes of dinosaur species during this time.

  17. Fundamentals, beliefs, and financial contagion

    Microsoft Academic Search

    Roberto Chang; Giovanni Majnoni

    2002-01-01

    We study contagion in a model in which financial crises can occur due to both weak fundamentals and adverse self-fulfilling expectations. Contagion emerges only if a crisis in one country leads international investors to rationally update beliefs about fundamentals in other countries. But purely expectational crises may be contagious, as investors may infer that fundamentals are weak. Hence, the structure

  18. Pitch Extraction and Fundamental Frequency

    E-print Network

    Regina, University of

    Pitch Extraction and Fundamental Frequency: History and Current Techniques David Gerhard Technical and Fundamental Frequency: History and Current Techniques David Gerhard Abstract: Pitch extraction (also called fundamental frequency estimation) has been a popular topic in many fields of research since the age

  19. Fundamentals of Carrier Transport

    NASA Astrophysics Data System (ADS)

    Lundstrom, Mark

    2000-11-01

    Fundamentals of Carrier Transport explores the behavior of charged carriers in semiconductors and semiconductor devices for readers without an extensive background in quantum mechanics and solid-state physics. This second edition contains many new and updated sections, including a completely new chapter on transport in ultrasmall devices and coverage of "full band" transport. Lundstrom also covers both low- and high-field transport, scattering, transport in devices, and transport in mesoscopic systems. He explains in detail the use of Monte Carlo simulation methods and provides many homework exercises along with a variety of worked examples. What makes this book unique is its broad theoretical treatment of transport for advanced students and researchers engaged in experimental semiconductor device research and development.

  20. Wall of fundamental constants

    SciTech Connect

    Olive, Keith A. [William I. Fine Theoretical Physics Institute, University of Minnesota, Minneapolis, Minnesota, 55455 (United States); School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota, 55455 (United States); Peloso, Marco [School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota, 55455 (United States); Uzan, Jean-Philippe [Institut d'Astrophysique de Paris, UMR-7095 du CNRS, Universite Pierre et Marie Curie, 98 bis bd Arago, 75014 Paris (France); Department of Mathematics and Applied Mathematics, Cape Town University, Rondebosch 7701 (South Africa); National Institute for Theoretical Physics (NITheP), Stellenbosch 7600 (South Africa)

    2011-02-15

    We consider the signatures of a domain wall produced in the spontaneous symmetry breaking involving a dilatonlike scalar field coupled to electromagnetism. Domains on either side of the wall exhibit slight differences in their respective values of the fine-structure constant, {alpha}. If such a wall is present within our Hubble volume, absorption spectra at large redshifts may or may not provide a variation in {alpha} relative to the terrestrial value, depending on our relative position with respect to the wall. This wall could resolve the contradiction between claims of a variation of {alpha} based on Keck/Hires data and of the constancy of {alpha} based on Very Large Telescope data. We derive the properties of the wall and the parameters of the underlying microscopic model required to reproduce the possible spatial variation of {alpha}. We discuss the constraints on the existence of the low-energy domain wall and describe its observational implications concerning the variation of the fundamental constants.

  1. OneGeology-Europe Plus Initiative

    NASA Astrophysics Data System (ADS)

    Capova, Dana; Kondrova, Lucie

    2014-05-01

    The Geological Surveys of the European countries hold valuable resources of geological data but, to discover, understand and use this data efficiently, a good level of standardization is essential. The OneGeology-Europe project had the aim of making geological maps at a scale 1:1M from Europe discoverable and accessible, available under a common data license and described by multilingual metainformation. A harmonized specification for basic geological map data was developed so that significant progress towards harmonizing the datasets was achieved. Responsibility for the management of the OneGeology-Europe portal has been taken by EuroGeoSurveys and provided by CGS and BRGM. Of the 34 members of EuroGeoSurveys (EGS), only 20 participated in the OneGeology-Europe project (Belgium, Czech Republic, Denmark, Estonia, Finland, France, Germany, Hungary, Ireland, Italy, Luxembourg, Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Sweden, Spain, United Kingdom), so the European area was not completely covered. At the 33rd General Meeting and Directors Workshop in 2012 it was therefore decided to establish a successor initiative OneGeology Europe Plus (1G-E+) with the purpose of extending the coverage by geological maps at a scale of 1:1 M to all the EGS member countries (including Albania, Austria, Bulgaria, Croatia, Cyprus, Greece, Iceland, Lithuania, Malta, Romania, Russia, Switzerland, Turkey, Ukraine) and also, if possible, to the other European countries (Belorussia, Bosnia and Herzegovina, Faeroe Islands, Kosovo, Latvia, Macedonia, Moldavia, Montenegro, Serbia). In order to achieve the desired result, it has been necessary for the new GSOs who intend to supply the additional 1G-E standardized services to carry out the work using their own staff and resources. The technical guidance and other support have been provided by the 1G-E+ Technical Support Team, funded from the internal budgets of their respective surveys. The team is coordinated by the Czech Geological Survey (CGS) working with the Bureau de Recherches Géologiques et Miničres (BRGM), the British Geological Survey (BGS), the Geological Survey of Denmark and Greenland (GEUS) and the Geological Survey of Slovenia (GeoZS). The Geological Survey of the Netherlands (TNO) decided to provide financial support for the initiative. The Technical Support Team has been providing the technical advice required to enable the inclusion of geological maps from new countries in the 1G-E Portal using the standards developed and accepted for 1G-E. Cookbooks, on-line help and a helpdesk are provided during the work. A technical workshop was organized at which all the technical steps required to reach the target solution were presented and discussed. All newcomers must agree the existing common license that was created for downloading the 1G-E data. It should be emphasized that the results will be displayed as part of the 1G-E project and metadata/portal infrastructures. The process is still ongoing because the harmonization work for most of the countries involved has been a demanding process. Some countries are facing difficulties because of the lack of expert personnel or insufficient resources of data. Despite some problems, the 1G-E+ initiative and the work involved has contributed to effective networking and technical cooperation between the GSOs across the wider European region.

  2. Geology and insolation-driven climatic history of Amazonian north polar materials on Mars.

    PubMed

    Tanaka, Kenneth L

    2005-10-13

    Mariner 9 and Viking spacecraft images revealed that the polar regions of Mars, like those of Earth, record the planet's climate history. However, fundamental uncertainties regarding the materials, features, ages and processes constituting the geologic record remained. Recently acquired Mars Orbiter Laser Altimeter data and Mars Orbiter Camera high-resolution images from the Mars Global Surveyor spacecraft and moderately high-resolution Thermal Emission Imaging System visible images from the Mars Odyssey spacecraft permit more comprehensive geologic and climatic analyses. Here I map and show the history of geologic materials and features in the north polar region that span the Amazonian period (approximately 3.0 Gyr ago to present). Erosion and redeposition of putative circumpolar mud volcano deposits (formed by eruption of liquefied, fine-grained material) led to the formation of an Early Amazonian polar plateau consisting of dark layered materials. Crater ejecta superposed on pedestals indicate that a thin mantle was present during most of the Amazonian, suggesting generally higher obliquity and insolation conditions at the poles than at present. Brighter polar layered deposits rest unconformably on the dark layers and formed mainly during lower obliquity over the past 4-5 Myr (ref. 20). Finally, the uppermost layers post-date the latest downtrend in obliquity <20,000 years ago. PMID:16222294

  3. Interpolation in digital modems. I. Fundamentals

    Microsoft Academic Search

    Floyd M. Gardner

    1993-01-01

    Timing adjustment in a digital modem must be performed by interpolation if sampling is not synchronized to the data symbols. The author describes the fundamental equation for interpolation, proposes a method for control, and outlines the signal-processing characteristics appropriate to an interpolator. A review of previous results and a tutorial exposition of the subject are given, along with new results

  4. Fundamental Cycles in Learning Algebra: An Analysis

    Microsoft Academic Search

    John Pegg

    Over the past 10 years a range of learning theories have appeared in which certain fundamental cycles of learning have been used to describe development of algebraic ideas. In this paper we consider the SOLO Model (Biggs & Collis, 1991) and compare and contrast it with various theories of process-object encapsulation (e.g., Dubinsky, 1991; Gray & Tall, 1994; Sfard, 1995).

  5. Progress of fundamental research in Wilms' tumor

    Microsoft Academic Search

    J. G. Wen; G. J. van Steenbrugge; R. M. Egeler; R. M. Nijman

    1997-01-01

    The progress of fundamental research on the histopathological and molecular genetic properties, model systems, growth factor involvement, and tumor markers of clinical nephroblastoma (Wilms' tumor) are reviewed. Histologically, Wilms' tumor (WT) has been found to reveal a disorganized renal developmental process in which blastema and epithelia are randomly interspersed in varying amounts of stroma. Anaplasia is the only criterion for

  6. State geological surveys: Their growing national role in policy

    USGS Publications Warehouse

    Gerhard, L.C.

    2000-01-01

    State geological surveys vary in organizational structure, but are political powers in the field of geology by virtue of their intimate knowledge of and involvement in legislative and political processes. Origins of state geological surveys lie in the recognition of society that settlement and prosperity depended on access to a variety of natural resources, resources that are most familiar to geologists. As the surveys adapt to modern societal pressures, making geology serve the public has become the new mission for many state geological surveys. Geologic mapping was the foundation of most early surveys, and the state surveys have brought mapping back into the public realm to meet today's challenges of growing population density, living environment desires, and resource access.

  7. Activities in planetary geology for the physical and earth sciences

    NASA Technical Reports Server (NTRS)

    Dalli, R.; Greeley, R.

    1982-01-01

    A users guide for teaching activities in planetary geology, and for physical and earth sciences is presented. The following topics are discussed: cratering; aeolian processes; planetary atmospheres, in particular the Coriolis Effect and storm systems; photogeologic mapping of other planets, Moon provinces and stratigraphy, planets in stereo, land form mapping of Moon, Mercury and Mars, and geologic features of Mars.

  8. The History of the Earth: Darwin, Geology and Landscape Art

    E-print Network

    of geological time, all of human history was but a fleeting moment. Charles Darwin surely had such ideas in mind necessary for what he believed to be the very slow process of evolution by natural selection. In Origin#12;2 The History of the Earth: Darwin, Geology and Landscape Art REBECCA BEDELL Nineteenth

  9. Geological and mathematical framework for failure modes in granular rock

    E-print Network

    Borja, Ronaldo I.

    Geological and mathematical framework for failure modes in granular rock Atilla Aydina, *, Ronaldo processes in granular rock and provide a geological framework for the corresponding structures. We describe show that sharp structures overlap older narrow tabular structures in the same rock. This switch

  10. Preliminary Surficial Geology of the Dove Spring Off-Highway Vehicle Open Area, Mojave Desert, California

    USGS Publications Warehouse

    Miller, David M.; Amoroso, Lee

    2007-01-01

    Introduction As part of a U.S. Geological Survey (USGS) monitoring plan to evaluate the environmental impact of off-highway vehicle (OHV) use on Bureau of Land Management (BLM) land in California, this report presents results of geologic studies in the Dove Spring OHV Open Area. This study produced baseline data, which when combined with historic and current patterns of land use, forms the basis for vegetation and wildlife monitoring designed to address the following questions: 1. Is the density and length of OHV routes increasing? 2. Are there cumulative effects of past and current OHV use associated with changes in the environmental integrity of soils, plants, and wildlife? 3. Is the spread of invasive species associated with levels of OHV use? 4. Is there a threshold of OHV impact that might be translated to management action by the BLM? The monitoring studies will be used to collect baseline environmental information to determine levels of environmental impact of OHV use. This approach will use a low-impact area as a proxy for pre-impact conditions (substituting space for time) to determine thresholds of OHV impacts beyond which environmental integrity is affected. Indicators of environmental integrity will emphasize factors that are fundamental to ecosystem structure and function and likely to be sensitive to OHV impacts. Surficial geology is studied because material properties such as texture and chemistry strongly control soil moisture and nutrient availability and therefore affect plant growth and distribution. An understanding of surficial geology can be used to predict and extrapolate soil properties and improve understanding of vegetation assemblages and their distribution. In the present study, vegetation associations may be examined as a function of surficial geology as well as other environmental variables such as slope, aspect, NRCS (National Resources Conservation Service) soil classification, elevation, and land-use history. Ground measurements of vegetation, biological soil crusts, compaction, and other information may be correlated with land use to identify possible ecological thresholds in OHV use that require monitoring. Surficial geology is relevant for several other studies of OHV impact, such as soil compaction, dust emissions, and acceleration of erosion. Compaction, reduced infiltration, and accelerated erosion have been documented in Dove Spring Canyon because of OHV use (Snyder and others, 1976) and elsewhere in the Mojave Desert (e.g., Webb, 1983; Langdon, 2000). A surficial geologic map enables the use of geomorphic process models, which when combined with measured soil properties, such as texture, nutrient chemistry, and bulk density, allows spatial extrapolation of the properties. Maps can be produced that predict compaction susceptibility, moisture conditions, dust emissions, flood hazards, and erodibility, among other applications.

  11. Geology Before Pluto: Pre-encounter Considerations

    NASA Astrophysics Data System (ADS)

    Moore, Jeffrey

    2014-05-01

    Jeffrey M. Moore (NASA Ames) and the New Horizons Science Team 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 prospects for endogenic activity in the form of tectonics and cryo-volcanism.

  12. NADM Conceptual Model 1.0 -- A Conceptual Model for Geologic Map Information

    USGS Publications Warehouse

    North American Geologic Map Data Model (NADM) Steering Committee Data Model Design Team

    2004-01-01

    Executive Summary -- The NADM Data Model Design Team was established in 1999 by the North American Geologic Map Data Model Steering Committee (NADMSC) with the purpose of drafting a geologic map data model for consideration as a standard for developing interoperable geologic map-centered databases by state, provincial, and federal geological surveys. The model is designed to be a technology-neutral conceptual model that can form the basis for a web-based interchange format using evolving information technology (e.g., XML, RDF, OWL), and guide implementation of geoscience databases in a common conceptual framework. The intended purpose is to allow geologic information sharing between geologic map data providers and users, independent of local information system implementation. The model emphasizes geoscience concepts and relationships related to information presented on geologic maps. Design has been guided by an informal requirements analysis, documentation of existing databases, technology developments, and other standardization efforts in the geoscience and computer-science communities. A key aspect of the model is the notion that representation of the conceptual framework (ontology) that underlies geologic map data must be part of the model, because this framework changes with time and understanding, and varies between information providers. The top level of the model distinguishes geologic concepts, geologic representation concepts, and metadata. The geologic representation part of the model provides a framework for representing the ontology that underlies geologic map data through a controlled vocabulary, and for establishing the relationships between this vocabulary and a geologic map visualization or portrayal. Top-level geologic classes in the model are Earth material (substance), geologic unit (parts of the Earth), geologic age, geologic structure, fossil, geologic process, geologic relation, and geologic event.

  13. Fundamental plasma emission involving ion sound waves

    NASA Technical Reports Server (NTRS)

    Cairns, Iver H.

    1987-01-01

    The theory for fundamental plasma emission by the three-wave processes L + or - S to T (where L, S and T denote Langmuir, ion sound and transverse waves, respectively) is developed. Kinematic constraints on the characteristics and growth lengths of waves participating in the wave processes are identified. In addition the rates, path-integrated wave temperatures, and limits on the brightness temperature of the radiation are derived.

  14. Geology By Lightplane

    NSDL National Science Digital Library

    Maher, Louis J.

    In 1966, Professor Louis J. Maher of the University of Wisconsin-Madison's Department of Geology and Geophysics piloted a department-owned Cessna over the continental US taking photos for use in his geology courses. As Maher flew, his trusty co-pilot and graduate assistant, Charles Mansfield, snapped the photos. The resulting collection is an assortment of breathtaking images of classic geological features, now available online for noncommercial use by educators (download via FTP). Maher gives us birds-eye views of structural features in Wyoming's Wind River Range, sedimentary strata in Arches National Park and the Grand Canyon, glacial landscapes in Northern Minnesota, and ancient lava flows in Arizona, to name just a few.

  15. The geology of Ganymede

    NASA Technical Reports Server (NTRS)

    Shoemaker, E. M.; Lucchitta, B. K.; Wilhelms, D. E.; Plescia, J. B.; Squyres, S. W.

    1982-01-01

    A broad outline of the geologic history of Ganymede is presented, obtained from a first attempt to map the geology on a global scale and to interpret the characteristics of the observed geologic units. Features of the ancient cratered terrain such as craters and palimpsests, furrows and troughs, are discussed. The grooved terrain is described, including its sulci and cells, and the age relation of these units is considered along with the structure and origin of this terrain. The Gilgamesh Basin and Western Equatorial Basin in the post grooved terrain are treated, as are the bright and dark ray craters and the regolith. The development of all these regions and features is discussed in context. For the regolith, this includes the effect of water migration, sputtering, and thermal annealing. The histories of the ancient cratered terrain, the grooved terrain, and the post grooved terrain are presented.

  16. Minnesota Geological Survey

    NSDL National Science Digital Library

    Established in 1872 by the State of Minnesota as part of the University of Minnesota, the Minnesota Geological Survey (MGS) serves the people of Minnesota by providing systematic geoscience information to support the stewardship of water, land, and mineral resources. This rather lovely digital collection brings together a record of all items published by the MGS since its creation. Here, visitors will find documents, reports, maps, and GIS data for online viewing or downloading as well. The thematic collections here include the Aeromagnetic Map Series, the annual reports of the Minnesota Geological and Natural History Survey, and the wonderful county atlas series. Visitors with a penchant for geology, natural history, and geography will find much to enjoy here.

  17. Sedimentology and petroleum geology

    SciTech Connect

    Bjorlykke, K.

    1989-01-01

    In this introduction to sedimentology and petroleum geology the subjects, which are closely related but mostly treated separately, are integrated. The first part covers the basic aspects of sedimentology, sedimentary geochemistry and diagenesis, including brief discussions of flow in rivers and channels, types of sediment transport, lake and river deposits, deltas (river-dominated, tide-dominated, and wave-dominated) and the water budget. Principles of stratigraphy, seismic stratigraphy and basin modeling form the basis for the last part on petroleum geology. Here subjects include the composition of kerogen and hydrocarbons, theories of migration and trapping of hydrocarbons and properties of reservoir rocks. Finally, short introductions to well logging and production geology are given.

  18. Global sedimentary geology program

    SciTech Connect

    Ginsburg, R.N.; Clifton, H.E.; Weimer, R.J.

    1986-07-01

    The Society of Economic Paleontologists and Mineralogists, in collaboration with the International Association of Sedimentologists and the International Union of Geological Sciences Committee on Sedimentology, is developing a new international study under the provisional title of Global Sedimentary Geology Program (GSGP). Initially, three research themes are being considered: (1) event stratigraphy-the documentation of examples of mass extinctions, eustatic fluctuations in sea level, major episodes of volcanisms, and changes in ocean composition; (2) facies models in time and space-an expansion of the existing data base of examples of facies models (e.G., deltas, fluvial deposits, and submarine fans) and global-scale study of the persistence of facies at various times in geologic history; and (3) sedimentary indices of paleogeography and tectonics-the use of depositional facies and faunas in paleogeography and in assessing the timing, locus, and characteristics of tectonism. Plans are being developed to organize pilot projects in each of these themes.

  19. Geological fakes and frauds

    NASA Astrophysics Data System (ADS)

    Ruffell, Alastair; Majury, Niall; Brooks, William E.

    2012-02-01

    Some geological fakes and frauds are carried out solely for financial gain (mining fraud), whereas others maybe have increasing aesthetic appeal (faked fossils) or academic advancement (fabricated data) as their motive. All types of geological fake or fraud can be ingenious and sophisticated, as demonstrated in this article. Fake gems, faked fossils and mining fraud are common examples where monetary profit is to blame: nonetheless these may impact both scientific theory and the reputation of geologists and Earth scientists. The substitution or fabrication of both physical and intellectual data also occurs for no direct financial gain, such as career advancement or establishment of belief (e.g. evolution vs. creationism). Knowledge of such fakes and frauds may assist in spotting undetected geological crimes: application of geoforensic techniques helps the scientific community to detect such activity, which ultimately undermines scientific integrity.

  20. Geology for Everyone

    NSDL National Science Digital Library

    This Geological Survey of Ireland website can increase the public's excitement about geology by offering simple, straightforward materials on the basics of geology. The website is divided into numerous themes such as Volcanoes, Rocks, Caves, and the Water Cycle. The links from each of the headings introduce the topic with simple descriptions and remarkable pictures and offer easy experiments when applicable. Students and educators can take virtual tours of the Ox Mountains, Killiney Beach, and other Irish landscapes. Everyone should visit the Landscapes for the Living link, which offers outstanding images of the diverse landscapes of Europe. While some of the themes are currently under construction, including Planet Earth, Plate Tectonics, and Earthquakes, the authors indicate that these materials will be added in the near future.

  1. Geologic guide to the island of Hawaii: A field guide for comparative planetary geology

    NASA Technical Reports Server (NTRS)

    Greeley, R. (editor)

    1974-01-01

    With geological data available for all inner planets except Venus, we are entering an era of true comparative planetary geology, when knowledge of the differences and similarities for classes of structures (e.g., shield volcanoes) will lead to a better understanding of general geological processes, regardless of planet. Thus, it is imperative that planetologists, particularly those involved in geological mapping and surface feature analysis for terrestrial planets, be familiar with volcanic terrain in terms of its origin, structure, and morphology. One means of gaining this experience is through field trips in volcanic terrains - hence, the Planetology Conference in Hawaii. In addition, discussions with volcanologists at the conference provide an important basis for establishing communications between the two fields that will facilitate comparative studies as more data become available.

  2. Lunar Crustal Magnetism: Correlations with Geology

    NASA Technical Reports Server (NTRS)

    Halekas, J. S.; Mitchell, D. L.; Lin, R. P.; Frey, S.; Acuna, M. H.; Hood, L. L.; Binder, A. B.

    2001-01-01

    With Lunar Prospector reflectometry data we now have sufficient surface coverage to allow detailed comparisons between crustal magnetism and geology. We find substantial evidence that lunar magnetism is dominated by the effects of impact processes. Additional information is contained in the original extended abstract.

  3. The Geology of Comet 19/P Borrelly

    NASA Technical Reports Server (NTRS)

    Britt, D. T.; Boice, D. C; Buratti, B. J.; Hicks, M. D.; Nelson, R. M.; Oberst, J.; Sandel, B. R.; Soderblom, L. A.; Stern, S. A.; Thomas, N.

    2002-01-01

    The Deep Space One spacecraft flew by Comet 19P/Borrelly on September 22, 2001 and returned a rich array of imagery with resolutions of up to 48 m/pixel. These images provide a window into the surface structure, processes, and geological history of a comet. Additional information is contained in the original extended abstract.

  4. Methods for probabilistic assessments of geologic hazards

    Microsoft Academic Search

    C. John Mann

    1988-01-01

    Although risk analysis today is considered to include three separate aspects (1) identifing sources of risk, (2) estimating probabilities quantitatively, and (3) evaluating consequences of risk, here only estimation of probabilities for natural geologic events, processes, and phenomena is addressed. Ideally, evaluation of potential future hazards includes an objective determination of probabilities that have been derived from past occurrences of

  5. Methods for probabilistic assessments of geologic hazards

    Microsoft Academic Search

    Mann

    1987-01-01

    Although risk analysis today is considered to include three separate aspects: (1) identifying sources of risk, (2) estimating probabilities quantitatively, and (3) evaluating consequences of risk, here, only estimation of probabilities for natural geologic events, processes, and phenomena is addressed. Ideally, evaluation of potential future hazards includes an objective determination of probabilities that has been derived from past occurrences of

  6. Ancient Martian Lakestands and Fluvial Processes in Iani Chaos: Geology of Light-Toned Layered Deposits and their Relationship to Ares Vallis Outflow Channels

    NASA Astrophysics Data System (ADS)

    Guallini, Luca; Gilmore, Martha; Marinangeli, Lucia; Thomas, Nicolas

    2015-04-01

    Iani Chaos is a ~30,000 square kilometers region that lies at the head of the Ares Vallis outflow channel system. Mapping of Ares Vallis reveals multiple episodes of erosion, probably linked to several discharge events from the Iani Chaos aquifer. We present the first detailed geomorphological map of the Iani region. Five chaos units have been distinguished with varying degrees of modification (primarily by erosion and fracturing), starting from a common terrain (Noachian highlands). We observe a general progressive decrease of their mean elevation from the Mesas, Mesas & Knobs and Hummocky (Hy) terrains to the Knobs and Knobby morphologies. This trend is consistent with an initial collapse of the original surface with an increase of the fracturing and/or of the erosion. Light-toned Layered Deposits (LLD) have been also mapped and described in Iani Chaos. These terrains are clearly distinguished by a marked light-toned albedo, high thermal inertia and a pervasively fractured morphology. LLD both fill the basins made by the collapsed chaotic terrains and are found to be partially modified by the chaos formation. LLD also overlap chaos mounds or are themselves eroded into mounds after deposition. These stratigraphic relationships demonstrate that LLD deposition occurred episodically in the Iani region and throughout the history of the development of the chaos. Water seems to have had an active role in the geological history of Iani. The composition and morphologies of the LLD are consistent with deposition in an evaporitic environment and with erosion by outflows, requiring stable water on the surface. For the first time, we have also mapped and analyzed potential fluvial features (i.e., channels, streamlined islands, terraces, grooved surfaces) on the surface of the LLD. These landforms describe a fluvial system that can be traced from central Iani and linked northward to Ares Vallis. Using topographic data, we have compared the elevation of the LLD and channel units and find that their altitudes are remarkably similar to the altitude of the floors of the major Ares Vallis channels. This is decisive evidence of 1) a possible fluvial system within Iani linked to the Ares Vallis outflow system, characterized by five episodes of outflow at least (S1 to S5), and 2) of the existence of the LLD within Iani during the occurrence of the outflows (i.e., the LLD are coeval with or postdate the Ares Vallis outflow channels). On the basis of our analysis, we propose the following formation model for Iani Chaos: 1) Initial fracturing and tectonic subsidence of the pristine Noachian materials and subsequent outflow erosion of the bedrock (Ares Vallis S1 channel origin); 2) Evaporitic deposition of older LLD units on top and between chaotic terrains. Layering suggests cyclic wetting and drying; 3) Tectonic subsidence and fluvial erosion of chaos and LLD (Ares Vallis S2 to S3 channels); 4) Deposition of younger LLD units in central and northern Iani; 5) Tectonic subsidence and outflows, erosion of chaos and LLD (Ares Vallis S4 to S5 channel origin and subsequent downdropping of NW and N(e) Iani).

  7. Roping Geologic Time

    NSDL National Science Digital Library

    Randall Richardson

    After having talked about the geologic time scale (Precambrian: prior to 570 Ma; Paleozoic: 570-245 Ma; Mesozoic: 245-65 Ma; Cenozoic: 65 Ma - Present), I ask for two volunteers from the class to hold a rope that is 50 feet long. I say that one end is the beginning of the Earth (4.6 billion years ago), and the other is today. I then give out 16 clothes pins and ask various students to put a cloths pin on the 'time line' at various 'geologic events'. For example, I ask them to put one where the dinosaurs died out (end of the Mesozoic). They almost invariably put it much too old (65 Ma is less than 2% of Earth history!). Then I ask them to put one on their birthday (they now laugh). Then I ask them to put one where we think hominoids (humans) evolved (~3-4 Ma), and they realize that we have not been here very long geologically. Then I ask them to put one at the end of the Precambrian, where life took off in terms of the numbers of species, etc. They are amazed that this only represents less than 15% of Earth history. Throughout the activity I have a quiz going on where the students calculate percentages of Earth History for major geologic events, and compare it to their own ages. On their time scale, the dinosaurs died only about two 'months' ago! The exercise is very effective at letting them get a sense of how long geologic time is, and how 'recently' some major geologic events happened when you consider a time scale that is the age of the earth.

  8. Reports of Planetary Geology and Geophysics Program, 1984

    NASA Technical Reports Server (NTRS)

    Holt, H. E. (compiler); Watters, T. R. (compiler)

    1985-01-01

    Topics include outer planets and satellites; asteroids and comets; Venus; lunar origin and solar dynamics; cratering process; planetary interiors, petrology, and geochemistry; volcanic processes; aeolian processes and landforms; fluvial processes; geomorphology; periglacial and permafrost processes; remote sensing and regolith studies; structure, tectonics, and stratigraphy; geological mapping, cartography, and geodesy; and radar applications.

  9. Fundamentals of Atmospheric Radiation

    NASA Astrophysics Data System (ADS)

    Bohren, Craig F.; Clothiaux, Eugene E.

    2006-02-01

    This textbook fills a gap in the literature for teaching material suitable for students of atmospheric science and courses on atmospheric radiation. It covers the fundamentals of emission, absorption, and scattering of electromagnetic radiation from ultraviolet to infrared and beyond. Much of the book applies to planetary atmosphere. The authors are physicists and teach at the largest meteorology department of the US at Penn State. Craig T. Bohren has taught the atmospheric radiation course there for the past 20 years with no book. Eugene Clothiaux has taken over and added to the course notes. Problems given in the text come from students, colleagues, and correspondents. The design of the figures especially for this book is meant to ease comprehension. Discussions have a graded approach with a thorough treatment of subjects, such as single scattering by particles, at different levels of complexity. The discussion of the multiple scattering theory begins with piles of plates. This simple theory introduces concepts in more advanced theories, i.e. optical thickness, single-scattering albedo, asymmetry parameter. The more complicated theory, the two-stream theory, then takes the reader beyond the pile-of-plates theory. Ideal for advanced undergraduate and graduate students of atmospheric science.

  10. Petroleum development geology

    SciTech Connect

    Dickey, P.A.

    1986-01-01

    An overview of geological concepts and reservoir engineering practices as they apply to the field of development (production) geology is presented. The author touches on nearly every aspect of the field in the 21 chapters of the book. He summarizes the basic depositional origin, sedimentary characteristics, and petrology of hydrocarbon-bearing rocks. He discusses physical properties, origin, and migration of subsurface oil and gas, oil field water, and their behavior, including subsurface pressures and fluid mechanics. Also covered are various methods of estimating reserves, the major tools of the trade and their limitations, and case histories.

  11. Introduction to Geology

    NSDL National Science Digital Library

    Jagoutz, Oliver

    If you are having difficulty remembering the details of the Earth's geological structure or the nature of major minerals and rock types, you can consult this excellent introductory course offered as part of MIT's OpenCourseWare initiative. The materials are drawn from Professors Perron and Jagoutz's 2011 "Introduction to Geology" course, and they include a number of lecture notes, available for download in PDF file format. The course is designed for undergraduates, though anyone can benefit from examining the materials. Visitors can make their way through lecture notes that cover metamorphic rocks, rock deformation, earthquakes, and the formation of continents.

  12. A generalized geologic map of Mars

    NASA Technical Reports Server (NTRS)

    Carr, M. H.; Masursky, H.; Saunders, R. S.

    1973-01-01

    A generalized geologic map of Mars has been constructed largely on the basis of differences in the topography of the surface. A number of topographic features on Mars whose form is highly diagnostic of their origin are shown. Of particular note are the shield volcanoes and lava plains. In some areas, the original features have been considerably modified by subsequent erosional and tectonic processes. These have not, however, resulted in homogenization of the planet's surface, but rather have emphasized its variegated character by leaving a characteristic imprint in specific areas. The topography of the planet, therefore, lends itself well to remote geologic interpretation.

  13. Geologic Maps and Structures Name ______________________________ Geology 100 Harbor section

    E-print Network

    Harbor, David

    in 3-D and to develop some facility in interpreting the nature of geologic structures from geologic maps and geologic cross sections. A big part of this task is developing a skill for thinking in 3-D shows the rocks that occur at the surface (or just below the soil) and is usually printed on top

  14. Solar astrophysical fundamental parameters

    NASA Astrophysics Data System (ADS)

    Meftah, M.; Irbah, A.; Hauchecorne, A.

    2014-08-01

    The accurate determination of the solar photospheric radius has been an important problem in astronomy for many centuries. From the measurements made by the PICARD spacecraft during the transit of Venus in 2012, we obtained a solar radius of 696,156±145 kilometres. This value is consistent with recent measurements carried out atmosphere. This observation leads us to propose a change of the canonical value obtained by Arthur Auwers in 1891. An accurate value for total solar irradiance (TSI) is crucial for the Sun-Earth connection, and represents another solar astrophysical fundamental parameter. Based on measurements collected from different space instruments over the past 35 years, the absolute value of the TSI, representative of a quiet Sun, has gradually decreased from 1,371W.m-2 in 1978 to around 1,362W.m-2 in 2013, mainly due to the radiometers calibration differences. Based on the PICARD data and in agreement with Total Irradiance Monitor measurements, we predicted the TSI input at the top of the Earth's atmosphere at a distance of one astronomical unit (149,597,870 kilometres) from the Sun to be 1,362±2.4W.m-2, which may be proposed as a reference value. To conclude, from the measurements made by the PICARD spacecraft, we obtained a solar photospheric equator-to-pole radius difference value of 5.9±0.5 kilometres. This value is consistent with measurements made by different space instruments, and can be given as a reference value.

  15. USGS Coastal and Marine Geology Infobank

    NSDL National Science Digital Library

    This clearinghouse provides organized access to U.S. Geological Survey (USGS) coastal and marine data and metadata. The facilities section features material on Coastal and Marine Geology (CMG) regional centers such as maps and information about staff, facilities, labs, research libraries and archives. The Atlas includes maps for specific geographic areas and information about specific types of data within the area such as bathymetry, gravity, magnetics, sampling, and others. The Field Activities section provides information about specific data collection activities (date, place, crew, equipment used, data collected, publications). The Field Activity Collection System (FACS) provides information about field activities (overviews, crew lists, equipment lists, and events). The "Geology School" provides general, broad-based information about earth science concepts, processes and terminology, indexed to keywords. There is also a set of links to additional databases, software tools and viewers, and to related topics.

  16. Wave Propagation in Jointed Geologic Media

    SciTech Connect

    Antoun, T

    2009-12-17

    Predictive modeling capabilities for wave propagation in a jointed geologic media remain a modern day scientific frontier. In part this is due to a lack of comprehensive understanding of the complex physical processes associated with the transient response of geologic material, and in part it is due to numerical challenges that prohibit accurate representation of the heterogeneities that influence the material response. Constitutive models whose properties are determined from laboratory experiments on intact samples have been shown to over-predict the free field environment in large scale field experiments. Current methodologies for deriving in situ properties from laboratory measured properties are based on empirical equations derived for static geomechanical applications involving loads of lower intensity and much longer durations than those encountered in applications of interest involving wave propagation. These methodologies are not validated for dynamic applications, and they do not account for anisotropic behavior stemming from direcitonal effects associated with the orientation of joint sets in realistic geologies. Recent advances in modeling capabilities coupled with modern high performance computing platforms enable physics-based simulations of jointed geologic media with unprecedented details, offering a prospect for significant advances in the state of the art. This report provides a brief overview of these modern computational approaches, discusses their advantages and limitations, and attempts to formulate an integrated framework leading to the development of predictive modeling capabilities for wave propagation in jointed and fractured geologic materials.

  17. Fundamentals of Airframe Repair

    NSDL National Science Digital Library

    On this site, visitors will find introductory materials to airframes and airframe repair for helicopters and airplanes. The resource is divided into two parts; part one discusses the basic components and processes of airframes, and part two covers airframe damage repair. Additionally, each part is broken down into four lessons, including Aviation Hardware, Structural Repair, and Metal-Working Processes. The text of the material is supplemented with helpful labeled drawings to illustrate each part of the airframe. This resource is useful for students who are just beginning in the field of airframe maintenance and repair, or the more general fields of aeronautics or aeronautical engineering.

  18. Plasma & RF Fundamentals

    NSDL National Science Digital Library

    This is a description for a learning module from Maricopa Advanced Technology Education Center. This PDF describes the module; access may be purchased by visiting the MATEC website. One third of modern semiconductor process steps and a variety of other applications employ plasma technology. RF energy is commonly used to generate and maintain a plasma which accelerates chemical processes or provides other desired outcomes such as light emission. This module is the first in a series that builds a knowledge foundation for understanding plasma technology and RF energy. Concepts and principles covered include particle behavior under plasma conditions, changes in electromagnetic wave forms, and related variables that affect RF/plasma applications.

  19. THE ASSESSMENT OF GEOLOGICAL HAZARDS AND DISASTERS IN NEWFOUNDLAND: AN UPDATE

    Microsoft Academic Search

    M. Batterson; D. G. E. Liverman; J. Ryan; D. Taylor

    A geological disaster occurs when natural geological processes impact on our activities, either through loss of life or injury, or through economic loss. A geological hazard is a potential disaster. Many Newfoundland communities have devel- oped at the base of steep slopes and are, therefore, prone to landslides and avalanches, or are built adjacent to the coast and are susceptible

  20. VISITORS' GEOLOGICAL CONCEPTIONS AND MEANING MAKING AT PETRIFIED FOREST NATIONAL PARK

    Microsoft Academic Search

    Nievita F. Bueno Watts; Steven Semken; Monica Pineda; Cheryl Alvarado

    When observing the natural landscape at National Parks, how do visitors make meaning of the geology? Interpretative geologic displays and programs here are typically uninformed by knowledge of visitor conceptions. Visitors' ideas about geological processes and landscape formation at Petrified Forest National Park in Arizona were investigated by interviewing 80 visitor groups (N= 235) at a landscape overlook and analyzing

  1. Planetary Geology: A Teacher's Guide with Activities in Physical and Earth Sciences.

    ERIC Educational Resources Information Center

    National Aeronautics and Space Administration, Washington, DC.

    This educator's guide discusses planetary geology. Exercises are grouped into five units: (1) introduction to geologic processes; (2) impact cratering activities; (3) planetary atmospheres; (4) planetary surfaces; and (5) geologic mapping. Suggested introductory exercises are noted at the beginning of each exercise. Each activity includes an…

  2. Advances in planetary geology

    NASA Technical Reports Server (NTRS)

    1984-01-01

    A wide variety of topics on planetary geology are presented. Subjects include stratigraphy and geomorphology of Copernicus, the Mamers valle region, and other selected regions of Mars and the Moon. Crater density and distribution are discussed for Callisto and the lunar surface. Spectroscopic analysis is described for Europa and Ganymede.

  3. IDAHO FLUVIAL GEOLOGY

    EPA Science Inventory

    Restricted availability. Major Attributes: Polygons described by geologic type codes & descriptions. May be incorporated into maps at the state/county/basin scale. Probably too coarse for use at the site scale. Scale: 1:500:000. Extent: Idaho. Projection: Albers. Source: ...

  4. Geology by Lightplane

    NSDL National Science Digital Library

    Louis J. Maher

    This site is a collection of aerial images of US geological features. Detailed 2000-pixel-wide JPEG versions of these photos (averaging 1MB in size and suitable for video projection or for slides) can be down-loaded from an FTP site. There are also text captions for the photographs.

  5. Geologic evolution of Arizona

    Microsoft Academic Search

    J. P. Penny; S. J. Reynolds

    1989-01-01

    Seven years in the making, the 35 papers in this volume summarize the stratigraphic, structural, and tectonic evolution of Arizona from Precambrian through Quaternary time. Intended as a compendium of current knowledge of Arizona geology, the papers synthesize previous work with new data, ideas, and concepts as well as identifying unresolved problems for future research. Emphasis is placed on the

  6. Geology of Wisconsin.

    ERIC Educational Resources Information Center

    Madison Public Schools, WI.

    Included are a teacher's guidebook and two filmstrips, "Geology of Wisconsin," and associated materials. The following are described: outline of objectives; suggested use of the filmstrips and guidebook; outline of the filmstrip content; four pages of illustrations suitable for duplication; a test for each filmstrip; and a list of additional…

  7. Soviet geology, 1976

    Microsoft Academic Search

    V. A. Vakhrameyev

    1976-01-01

    The geological history of the Jurassic period shows that the most abrupt change in physiogeographical, and particularly in climatic, conditions occured not at its lower or upper limit but at the boundary between the middle and late epochs. This is shown especially clearly by a study of the lacustral and continental sediments which form such a significant feature of the

  8. Geological and Inorganic Materials.

    ERIC Educational Resources Information Center

    Jackson, L. L.; And Others

    1989-01-01

    Presents a review focusing on techniques and their application to the analysis of geological and inorganic materials that offer significant changes to research and routine work. Covers geostandards, spectroscopy, plasmas, microbeam techniques, synchrotron X-ray methods, nuclear activation methods, chromatography, and electroanalytical methods.…

  9. Dinosaur Paleobiology Geology 331

    E-print Network

    Kammer, Thomas

    Dinosaur Paleobiology Geology 331 Paleontology #12;Dinosaurs are popular with the public #12;Jack Horner, Montana State Univ. #12;Field Work in Montana #12;A dinosaur "drumstick" in its field jacket. #12;Abundant vascular canals in dinosaur bone support the warm- blooded theory #12;Thin section of dinosaur

  10. Geological impacts on nutrition

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This chapter reviews the nutritional roles of mineral elements, as part of a volume on health implications of geology. The chapter addresses the absorption and post-absorptive utilization of the nutritionally essential minerals, including their physiological functions and quantitative requirements....

  11. Glacial Geology of Wisconsin.

    ERIC Educational Resources Information Center

    Madison Public Schools, WI.

    This publication is a teacher's resource and guidebook for the presentation of the three filmstrips in the "Glacial Geology of Wisconsin" series. The first filmstrip is subtitled, "Evidence of the Glaciers," the second "How the Glaciers Reshaped the Landscape," and the third "Fossils of the Ice Age." Included are a list of objectives, an outline…

  12. Appendix E: Geology

    SciTech Connect

    Reidel, Steve; Chamness, Mickie A.

    2008-01-17

    This appendix provides a detailed description of geology under the Central Plateau of the Hanford Site, emphasizing the areas around tank farms. It is to be published by client CH2M HILL Hanford Group, Inc., as part of a larger, multi-contractor technical report.

  13. American Geological Institute Homepage

    NSDL National Science Digital Library

    This is the homepage of the American Geological Institute (AGI). Visitors can access information about geoscience education, public policy, environmental geoscience, careers in geoscience, publications, news articles, and events. Materials presented here include databases, curriculum materials, legislation and appropriations information, and an image bank.

  14. Geological Time Machine

    NSDL National Science Digital Library

    Allen Collins

    This University of California site provides an interactive geologic time scale to explore the history of the Earth. Beginning in the Precambrian Eon (4.6 million years ago) and ending today (Holocene Epoch), each Epoch, Period, Era, and Eon are covered. Information provided includes ancient life, dates, descriptions of major events, localities, tectonics, and stratigraphy. Links to additional resources are also available.

  15. Analysis of geological events

    Microsoft Academic Search

    K. L. Burns

    1975-01-01

    Geological events, such as emplacement of granite or growth of slaty cleavage, may be ordered into a sequence by two methods. One is to assign each event a place in a time scale, such as years before the present, which amounts to assigning events an age designation from the set of real numbers. In ordering such a list, the algebra

  16. Geology Fieldnotes: Noatak National Monument

    NSDL National Science Digital Library

    This feature discusses the geologic framework, history, tectonic setting, and soil and rock types of Northwest Alaska, as seen in the Noatak National Monument. Links are also provided to maps, visitor information, and to geological and conservation organizations.

  17. Geology of California. Second Edition

    SciTech Connect

    Norris, R.M.; Webb, R.W.

    1990-01-01

    Two introductory chapters familiarize readers with basic geologic concepts. The following chapters describe the geology of each of California's 11 geomorphic provinces; the San Andreas fault and offshore geology are discussed in two separate chapters. Four appendices acquaint readers with technical words and terms, common minerals and rocks in California, geologic time, and geologic theories that pertain to California. During the 1960s evidence collected from the east Pacific sea floor off the western coast of North America gave scientists supporting data for Alfred Wegener's 1910 theory of continental drift. In addition to the confirmation of continental drift, since the 1960s scientists have discovered paleomagnetism, sea-floor spreading, exotic and suspect terranes, and polar wandering. These important concepts have had far reaching effects about how we understand the geology of California and how this region has evolved through geologic time. Improved investigative procedures enable earth scientists to comprehend previously puzzling aspects of California's geology.

  18. A Study of the Education of Geology

    NASA Astrophysics Data System (ADS)

    Berglin, R. S.; Baldridge, A. M.; Buxner, S.; Crown, D. A.

    2013-12-01

    An Evaluation and Assessment Method for Workshops in Science Education and Resources While many professional development workshops train teachers with classroom activities for students, Workshops in Science Education and Resources (WISER): Planetary Perspectives is designed to give elementary and middle school teachers the deeper knowledge necessary to be confident teaching the earth and space science content in their classrooms. Two WISER workshops, Deserts of the Solar System and Volcanoes of the Solar System, place an emphasis on participants being able to use learned knowledge to describe or 'tell the story of' a given rock. In order to understand how participants' knowledge and ability to tell the story changes with instruction, we are investigating new ways of probing the understanding of geologic processes. The study will include results from both college level geology students and teachers, focusing on their understanding of geologic processes and the rock cycle. By studying how new students process geologic information, teachers may benefit by learning how to better teach similar information. This project will help to transfer geologic knowledge to new settings and assess education theories for how people learn. Participants in this study include teachers participating in the WISER program in AZ and introductory level college students at St. Mary's College of California. Participants will be videotaped drawing out their thought process on butcher paper as they describe a given rock. When they are done, they will be asked to describe what they have put on the paper and this interview will be recorded. These techniques will be initially performed with students at St. Mary's College of California to understand how to best gather information. An evaluation of their prior knowledge and previous experience will be determined, and a code of their thought process will be recorded. The same students will complete a semester of an introductory college level Physical Geology course and then complete the assessment process, with the same rock again. Data will be compared to see how the thought process has changed. By studying the initial thought process, teachers can meet students at their level. At the end of the student research, this project will also be applied to elementary and middle school teachers in Tucson, Arizona at WISER workshops. This study will draw conclusions on how participants' thought processes change through WISER-type instruction.

  19. On Fundamental Groups Galois Closures

    E-print Network

    Rauhut, Holger

    . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57 Appendix to Section 5 . . . . . . . . . . . . . . . . . . . . . . . . . . 58 5.5 Group homology and complex projective curves the fundamental group determines the curve up to deformation of the complex

  20. Fundamental studies in geodynamics

    NASA Technical Reports Server (NTRS)

    Anderson, D. L.

    1980-01-01

    Progress in modeling instantaneous plate kinematics is reviewed, with emphasis on recently developed models of present day plate motions derived by the systematic inversion of globally distributed data sets. Rivera plate motions, the Caribbean South American boundary, Indian plate deformation, Pacific-North America, seismicity and subduction processes, and the study of slow earthquakes and free oscillations are discussed.

  1. The Geological Society Web Shop

    NSDL National Science Digital Library

    The Geological Society has launched an on-line bookshop, through which both Fellows and non-Fellows of the Society can purchase Geological Society books. Visitors can select books listed under the following headings: Tectonics, Economic Geology, Environmental, Petrology, Stratigraphy, Marine Studies, and Geophysics. The Geological Society Web Shop can be browsed or searched by keyword. Information on opening an account and purchasing books is available at the site.

  2. Earth Structure: An Introduction to Structural Geology and Tectonics

    NSDL National Science Digital Library

    Ben van der Pluijm

    This is the home page for Ben van der Pluijm's and Steve Marshak's structural geology textbook. This page contains a brief synopsis of each of the chapters in their text. The chapter summaries in total provide an overview of the basic principles of structural geology and tectonics. Section A. covers Fundamentals such as force, stress, deformation, strain and rheology; Section B. covers Brittle Structures (faults, veins and joints); Section C covers Ductile Structures (folds, fabrics, shear zones etc); and Section D. covers Tectonics and Regional Deformation. The page also contains structural and tectonic animations and links to numerous related web sites and professional organizations.

  3. The Belgian Research and Development Feasibility Programme for the Geological Disposal of High-Level and Long-Lived Radioactive Waste - 12338

    SciTech Connect

    Van Marcke, Philippe; Van Humbeeck, Hugues [ONDRAF/NIRAS (Belgium); Van Cotthem, Alain [TRACTEBEL GDF-Suez (Belgium)

    2012-07-01

    ONDRAF/NIRAS, the Belgian Agency for Radioactive Waste and Enriched Fissile Materials, considers geological disposal in the poorly indurated Boom Clay as the reference solution for the long-term management of high-level and/or long-lived radioactive waste. To develop a safety concept and design for geological disposal, ONDRAF/NIRAS follows an iterative process demonstrating that the repository will be both safe and feasible to implement. This process is called the safety strategy. A part of the safety strategy is the feasibility programme which aims at demonstrating, at a conceptual level, that the proposed geological disposal system can be constructed, operated and progressively closed. The followed methodology is based on the substantiation of a hierarchy of feasibility statements. These statements cover all activities from the removal of primary waste packages from interim storage buildings to the closure of the disposal site and a period of institutional control. They focus on engineering practicability, health and safety and environmental considerations, costs and quality assurance issues. A 4 year research project to support the R and D feasibility programme was launched in 2009 with several international partners coordinated by ONDRAF/NIRAS. It aims at confirming that there are no fundamental flaws or show-stoppers in the feasibility of building and operating the facilities for geological disposal in the Boom Clay. (authors)

  4. Structural Geology: Deformation of Rocks

    E-print Network

    Kammer, Thomas

    . · Rocks deform when applied stress exceeds rock strength. Deformation may be ductile flow or brittleStructural Geology: Deformation of Rocks Geology 200 Geology for Environmental Scientists #12;Major of Maine #12;Chevron folds in brittle rocks. An example of angle parallel folding. #12;Angle parallel

  5. Geologic Map of New Jersey

    NSDL National Science Digital Library

    This map displays the sedimentary rocks of the Cenozoic, Mesozoic, and Paleozoic eras as well as the igneous and metamorphic rocks of the Mesozoic and Precambrian eras. There is a pagesize copy of the geologic map, a brief description of the geology and physiographic provinces of New Jersey, and information on bedrock geologic maps of New Jersey (in CD-ROM format).

  6. The Second Flowering of Geology.

    ERIC Educational Resources Information Center

    Cloud, Preston

    1983-01-01

    Discusses two "golden" ages in geological investigations/inquiry. The first, extending from the late eighteenth century through the early nineteenth century, established geology as a science based on naturalistic principles. The second, beginning after World War II, is characterized by advances in geological specialities and explanations based on…

  7. Ordering Geologic Events and Interpreting Geologic History: The Grand Canyon

    NSDL National Science Digital Library

    Jennifer Wenner

    This activity is designed to help students recognize the connections among things like rock identification and map reading with the "story" that these things can tell us in terms of geologic history. Students have already learned about using observation to identify rocks and the principles of interpreting geologic cross-sections. The activity gives students practice in rock ID, topo map reading, geologic map reading and the aspects of geologic time. Students work with rock samples and a geologic map of the Grand Canyon to interpret a history for the area.

  8. USGS National Geologic Map Database: State-wide Geologic Maps

    NSDL National Science Digital Library

    This search tool provides descriptions and availability information for geologic maps of the 50 States, the District of Columbia, and Puerto Rico. These geologic maps are published by a variety of organizations, including State geologic agencies, the U.S. Geological Survey (USGS), universities, and private companies. Title, date, scale, publisher, series (where applicable), and basic ordering information is provided for each map. A place name search and an advanced search using geologic themes, areas, publishers and other criteria allow for more specific queries to the database.

  9. Significant achievements in the planetary geology program, 1980

    NASA Technical Reports Server (NTRS)

    Holt, H. E. (editor)

    1980-01-01

    Recent developments in planetology research as reported at the 1980 NASA Planetology Program Principal Investigators meeting are summarized. Important developments are summarized in topics ranging from solar system evolution and comparative planetology to geologic processes active on other planetary bodies.

  10. Significant achievements in the planetary geology program, 1981

    NASA Technical Reports Server (NTRS)

    Mouginis-Mark, P. J.

    1982-01-01

    Recent developments in planetology research are summarized. Important developments are summarized in topics ranging from solar system evolution, comparative planetology, and geologic processes, to techniques and instrument development for future exploration.

  11. 12.001 Introduction to Geology, Spring 2008

    E-print Network

    Elkins-Tanton, Lindy

    This undergraduate level course presents a basic study in geology. It introduces major minerals and rock types, rock-forming processes, and time scales; temperatures, pressures, compositions, structure of the Earth, and ...

  12. Significant achievements in the planetary geology program, 1975 - 1976

    NASA Technical Reports Server (NTRS)

    Head, J. W. (editor)

    1977-01-01

    Developments in planetology research as reported at the 1976 NASA Planetology Program Principal Investigators' meeting are summarized. Topics range from solar system evolution, comparative planetology, and geologic processes to techniques and instrument development for future exploration.

  13. Geologic Maps and Geologic Structures: A Texas Example

    NSDL National Science Digital Library

    Roger Steinberg

    This Historical Geology lab exercise is an accompaniment to lab class instruction about geologic structures (folding and faulting) and geologic maps. It also serves as an excellent introduction to the Geology of the state of Texas. "Coloring" geologic maps, an important part of the exercise, may seem like a very elementary learning technique. But this lab engages students actively, and since the subject is often already somewhat familiar to them, emphasizing both the geology and geography of Texas, students receive it enthusiastically. This activity could be adapted to other regions, since most states have color 8 1/2 by 11 geologic maps available. A color map could be scanned and modified in Photoshop to create a simplified black and white version as was done in the assignment handout.

  14. Fundamental investigation of duct/ESP phenomena

    SciTech Connect

    Brown, C.A. (Radian Corp., Austin, TX (United States)); Durham, M.D. (ADA Technologies, Inc., Englewood, CO (United States)); Sowa, W.A. (California Univ., Irvine, CA (United States). Combustion Lab.); Himes, R.M. (Fossil Energy Research Corp., Laguna Hills, CA (United States)); Mahaffey, W.A. (CHAM of North America, Inc., Huntsville, AL (United States))

    1991-10-21

    Radian Corporation was contracted to investigate duct injection and ESP phenomena in a 1.7 MW pilot plant constructed for this test program. This study was an attempt to resolve problems found in previous studies and answer remaining questions for the technology using an approach which concentrates on the fundamental mechanisms of the process. The goal of the study was to obtain a better understanding of the basic physical and chemical phenomena that control: (1) the desulfurization of flue gas by calcium-based reagent, and (2) the coupling of an existing ESP particulate collection device to the duct injection process. Process economics are being studied by others. (VC)

  15. SF STATE Extended Learning Fundamental

    E-print Network

    SF STATE Extended Learning 2013/2014 Fundamental Issues HUMAN RESOURCE MANAGEMENT www Extended Learning offers a: · Certificate in Human Resource Management: Fundamental Issues · Associate visit www.cel.sfsu.edu/hrm/ Please RSVP online at www.cel.sfsu.edu/hrm/events.cfm Program staff

  16. Fundamental physics with radio astronomy

    Microsoft Academic Search

    Michael Kramer

    2010-01-01

    Radio astronomy offers a unique way to study the fundamental forces in the Universe. We utilize this exciting window to probe fundamental physics on all scales -from the forces in super-dense matter, over precision tests of general relativity, to the large-scale cosmic magnetic fields. New technology promises to further revolutionize this field -as well as the rest of astronomy and

  17. Fundamental Neutron Physics at NIST

    NASA Astrophysics Data System (ADS)

    Arif, Muhammad

    2009-10-01

    The program in fundamental neutron physics at the National Institute of Standards and Technology (NIST) began nearly two decades ago. Currently, five neutron beam lines are dedicated to studies of fundamental neutron interactions. The neutrons are provided by the NIST Center for Neutron Research (NCNR), a national user facility for studies that include condensed matter physics, materials science, nuclear chemistry, and biological science. The beam lines for fundamental neutron physics experiments include a high intensity polychromatic beam, three monochromatic beams (0.496 nm, 0.89 nm, and .384 nm), and a neutron interferometer and optics facility (0.2 nm -- 0.49 nm). The presentation will discuss the broad program in fundamental neutron physics with a brief description of some of the experiments performed at the NCNR. In addition, the status of the new guide expansion project that includes a new neutron guide that will provide an additional very high intensity polychromatic beam for fundamental physics research will be presented.

  18. Information physics fundamentals of nanophotonics.

    PubMed

    Naruse, Makoto; Tate, Naoya; Aono, Masashi; Ohtsu, Motoichi

    2013-05-01

    Nanophotonics has been extensively studied with the aim of unveiling and exploiting light-matter interactions that occur at a scale below the diffraction limit of light, and recent progress made in experimental technologies--both in nanomaterial fabrication and characterization--is driving further advancements in the field. From the viewpoint of information, on the other hand, novel architectures, design and analysis principles, and even novel computing paradigms should be considered so that we can fully benefit from the potential of nanophotonics. This paper examines the information physics aspects of nanophotonics. More specifically, we present some fundamental and emergent information properties that stem from optical excitation transfer mediated by optical near-field interactions and the hierarchical properties inherent in optical near-fields. We theoretically and experimentally investigate aspects such as unidirectional signal transfer, energy efficiency and networking effects, among others, and we present their basic theoretical formalisms and describe demonstrations of practical applications. A stochastic analysis of light-assisted material formation is also presented, where an information-based approach provides a deeper understanding of the phenomena involved, such as self-organization. Furthermore, the spatio-temporal dynamics of optical excitation transfer and its inherent stochastic attributes are utilized for solution searching, paving the way to a novel computing paradigm that exploits coherent and dissipative processes in nanophotonics. PMID:23574991

  19. Fundamental Vocabulary Selection Based on Word Familiarity

    NASA Astrophysics Data System (ADS)

    Sato, Hiroshi; Kasahara, Kaname; Kanasugi, Tomoko; Amano, Shigeaki

    This paper proposes a new method for selecting fundamental vocabulary. We are presently constructing the Fundamental Vocabulary Knowledge-base of Japanese that contains integrated information on syntax, semantics and pragmatics, for the purposes of advanced natural language processing. This database mainly consists of a lexicon and a treebank: Lexeed (a Japanese Semantic Lexicon) and the Hinoki Treebank. Fundamental vocabulary selection is the first step in the construction of Lexeed. The vocabulary should include sufficient words to describe general concepts for self-expandability, and should not be prohibitively large to construct and maintain. There are two conventional methods for selecting fundamental vocabulary. The first is intuition-based selection by experts. This is the traditional method for making dictionaries. A weak point of this method is that the selection strongly depends on personal intuition. The second is corpus-based selection. This method is superior in objectivity to intuition-based selection, however, it is difficult to compile a sufficiently balanced corpora. We propose a psychologically-motivated selection method that adopts word familiarity as the selection criterion. Word familiarity is a rating that represents the familiarity of a word as a real number ranging from 1 (least familiar) to 7 (most familiar). We determined the word familiarity ratings statistically based on psychological experiments over 32 subjects. We selected about 30,000 words as the fundamental vocabulary, based on a minimum word familiarity threshold of 5. We also evaluated the vocabulary by comparing its word coverage with conventional intuition-based and corpus-based selection over dictionary definition sentences and novels, and demonstrated the superior coverage of our lexicon. Based on this, we conclude that the proposed method is superior to conventional methods for fundamental vocabulary selection.

  20. Extreme Events in the Geological Past

    NASA Astrophysics Data System (ADS)

    Herget, Jürgen

    Many Xevents in the geological past exceeded the strengths and intensities observed for modern-day natural events. The number of extraordinary events that occurred in the geological past is of course much larger than the number we witness today because the geological timescale covers millions of years. This contribution focuses on these Xevents from earth's geological history, including selected examples from plate tectonics, earth magnetism, ice age cycles, volcanism, earthquakes, meteorite impacts and floods. Events related to these processes occur on different timescales. For example, drastic modifications of atmospheric and oceanic circulation due to continental shift (which creates new mountain ranges and reshapes land masses and oceans) take millions of years, while meteorite impacts happen within seconds. However, any these processes can be the trigger for dramatic consequences, like mass extinctions of life, or global glaciations. An overview of a research program that considers historic and prehistoric flood events is given. Based on the water levels observed during floods, the palaeodischarge can be determined and used to improve the reliability of flood predictions. Investigations of Pleistocene ice-dammed lake outburst floods (the largest flood events in the Earth's history) are useful when developing new methods and techniques that can be applied to younger events of a smaller scale in other environments.