Science.gov

Sample records for geological events determining

  1. Techniques for determining probabilities of geologic events and processes

    SciTech Connect

    Hunter, R.L. ); Mann, C.J. )

    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.

  2. Techniques for determining probabilities of geologic events and processes

    SciTech Connect

    Hunter, R.L.; Mann, C.J.

    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.

  3. Discrete-event simulation of nuclear-waste transport in geologic sites subject to disruptive events. Final report

    SciTech Connect

    Aggarwal, S.; Ryland, S.; Peck, R.

    1980-06-19

    This report outlines a methodology to study the effects of disruptive events on nuclear waste material in stable geologic sites. The methodology is based upon developing a discrete events model that can be simulated on the computer. This methodology allows a natural development of simulation models that use computer resources in an efficient manner. Accurate modeling in this area depends in large part upon accurate modeling of ion transport behavior in the storage media. Unfortunately, developments in this area are not at a stage where there is any consensus on proper models for such transport. Consequently, our work is directed primarily towards showing how disruptive events can be properly incorporated in such a model, rather than as a predictive tool at this stage. When and if proper geologic parameters can be determined, then it would be possible to use this as a predictive model. Assumptions and their bases are discussed, and the mathematical and computer model are described.

  4. Seismic and geologic characteristics of drowning events on carbonate platforms

    SciTech Connect

    Erlich, R.N.; Barrett, S.E. )

    1990-05-01

    Carbonate platform drowning events were recorded in Late Jurassic-Early Cretaceous carbonates of the Baltimore Canyon area, and early Miocene carbonates of the Pearl River Mouth basin. Cursory examination of seismic data from both areas would suggest that the platforms appear to fit the classic definition of a drowning unconformity. Lithologic and paleontologic data however, indicate that depositional hiatuses vary widely in each area (from 0-25 Ma in the Baltimore Canyon area, to no hiatus, but a condensed section in the Pearl River Mouth basin). The sedimentary sequence produced during a drowning event (the drowning sequence) in both areas is gradational with underlying shallow platform carbonates and, in some places, overlying deeper marine limestones and shales. Facies models illustrate that drowning event, in general, can appear as instantaneous or gradual changes in lithologic and seismic data. However, evidence from platforms adjacent to continental margins (Baltimore Canyon) and isolated open ocean atolls and banks (Pearl River Mouth basin) indicates that their response to drowning is different. In addition, bypass/erosional and accretionary carbonate platforms also respond somewhat differently to drowning events. The geologic characteristics of drowning events on carbonate platforms include gradational lower (and sometimes upper) contacts, chemical sedimentation, open-marine shelf sediments, and variable loss of time at the upper boundary. Late-growth shelf margin reefs can also be a diagnostic feature of drowned platforms. Seismic characteristics include horizontal to subhorizontal basinal marine onlap and basin-parallel reflector continuity above the carbonate sequence boundary. Proper recognition of the seismic and geologic characteristics of drowning events can lead to better reservoir-seal predictions, and to correct reconstruction of the depositional and tectonic/eustatic history of an area.

  5. The Heavy Links between Geological Events and Vascular Plants Evolution: A Brief Outline.

    PubMed

    Piombino, Aldo

    2016-01-01

    Since the rise of photosynthesis, life has influenced terrestrial atmosphere, particularly the O2 and the CO2 content (the latter being originally more than 95%), changing the chemistry of waters, atmosphere, and soils. Billions of years after, a far offspring of these first unicellular forms conquered emerging lands, not only completely changing landscape, but also modifying geological cycles of deposition and erosion, many chemical and physical characteristics of soils and fresh waters, and, more, the cycle of various elements. So, there are no doubts that vascular plants modified geology; but it is true that also geology has affected (and, more, has driven) plant evolution. New software, PyRate, has determined vascular plant origin and diversification through a Bayesian analysis of fossil record from Silurian to today, particularly observing their origination and extinction rate. A comparison between PyRate data and geological history suggests that geological events massively influenced plant evolution and that also the rise of nonflowering seed plants and the fast diffusion of flowering plants can be explained, almost partly, with the environmental condition changes induced by geological phenomena.

  6. The Heavy Links between Geological Events and Vascular Plants Evolution: A Brief Outline

    PubMed Central

    Piombino, Aldo

    2016-01-01

    Since the rise of photosynthesis, life has influenced terrestrial atmosphere, particularly the O2 and the CO2 content (the latter being originally more than 95%), changing the chemistry of waters, atmosphere, and soils. Billions of years after, a far offspring of these first unicellular forms conquered emerging lands, not only completely changing landscape, but also modifying geological cycles of deposition and erosion, many chemical and physical characteristics of soils and fresh waters, and, more, the cycle of various elements. So, there are no doubts that vascular plants modified geology; but it is true that also geology has affected (and, more, has driven) plant evolution. New software, PyRate, has determined vascular plant origin and diversification through a Bayesian analysis of fossil record from Silurian to today, particularly observing their origination and extinction rate. A comparison between PyRate data and geological history suggests that geological events massively influenced plant evolution and that also the rise of nonflowering seed plants and the fast diffusion of flowering plants can be explained, almost partly, with the environmental condition changes induced by geological phenomena. PMID:26966609

  7. Geological Time, Biological Events and the Learning Transfer Problem

    ERIC Educational Resources Information Center

    Johnson, Claudia C.; Middendorf, Joan; Rehrey, George; Dalkilic, Mehmet M.; Cassidy, Keely

    2014-01-01

    Comprehension of geologic time does not come easily, especially for students who are studying the earth sciences for the first time. This project investigated the potential success of two teaching interventions that were designed to help non-science majors enrolled in an introductory geology class gain a richer conceptual understanding of the…

  8. Determination of carbonate carbon in geological materials by coulometric titration

    USGS Publications Warehouse

    Engleman, E.E.; Jackson, L.L.; Norton, D.R.

    1985-01-01

    A coulometric titration is used for the determination of carbonate carbon in geological materials. Carbon dioxide is evolved from the sample by the addition of 2 M perchloric acid, with heating, and is determined by automated coulometric titration. The coulometric titration showed improved speed and precision with comparable accuracy to gravimetric and gasometric techniques. ?? 1985.

  9. Geologic effects of the Greeley event, Nevada Test site

    USGS Publications Warehouse

    Dickey, Dayton Delbert; Jenkins, E.C.; McKeown, F.A.; Lee, W.H.

    1969-01-01

    The intermediate yield Greeley event, in which a nuclear device was detonated at a depth of 3,990 feet in Pahute Mesa at the Nevada Test Site, caused fracturing in rocks and spalling of rock from cliffs as far as 3 and 8 miles, respectively, from the detonation point.

  10. Flameless atomic-absorption determination of gold in geological materials

    USGS Publications Warehouse

    Meier, A.L.

    1980-01-01

    Gold in geologic material is dissolved using a solution of hydrobromic acid and bromine, extracted with methyl isobutyl ketone, and determined using an atomic-absorption spectrophotometer equipped with a graphite furnace atomizer. A comparison of results obtained by this flameless atomic-absorption method on U.S. Geological Survey reference rocks and geochemical samples with reported values and with results obtained by flame atomic-absorption shows that reasonable accuracy is achieved with improved precision. The sensitivity, accuracy, and precision of the method allows acquisition of data on the distribution of gold at or below its crustal abundance. ?? 1980.

  11. 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.

  12. Hydrological and Geological Features Contributing to a Seepage Event at Yucca Mountain

    NASA Astrophysics Data System (ADS)

    Fedors, R. W.; Smart, K. J.; Parrott, J. D.

    2006-05-01

    depressions or gullies). Analyses of the geological characteristics associated with the seepage location suggest the contributing factors that constrained seepage to this particular portion of the tunnel include (i) distance to the surface (i.e., ~60 m [200 ft]), (ii) gently dipping strata with distinct lithological contacts that may have laterally diverted water, (iii) faults and fractures, and (iv) downslope capping by rock units with different hydrological characteristics. This is an independent product of the CNWRA and does not necessarily reflect the views of regulatory positions of the NRC. The NRC staff views expressed herein are preliminary and do not constitute a final judgment or determination of the matters addressed or of the acceptability of a license application for a geologic repository at Yucca Mountain.

  13. Assessment of effectiveness of geologic isolation systems. Geologic factors in the isolation of nuclear waste: evaluation of long-term geomorphic processes and catastrophic events

    SciTech Connect

    Mara, S.J.

    1980-03-01

    SRI International has projected the rate, duration, and magnitude of geomorphic processes and events in the Southwest and Gulf Coast over the next million years. This information will be used by the Department of Energy`s Pacific Northwest Laboratory (PNL) as input to a computer model, which will be used to simulate possible release scenarios and the consequences of the release of nuclear waste from geologic containment. The estimates in this report, although based on best scientific judgment, are subject to considerable uncertainty. An evaluation of the Quaternary history of the two study areas revealed that each had undergone geomorphic change in the last one million years. Catastrophic events were evaluated in order to determine their significance to the simulation model. Given available data, catastrophic floods are not expected to occur in the two study areas. Catastrophic landslides may occur in the Southwest, but because the duration of the event is brief and the amount of material moved is small in comparison to regional denudation, such events need not be included in the simulation model. Ashfalls, however, could result in removal of vegetation from the landscape, thereby causing significant increases in erosion rates. Because the estimates developed during this study may not be applicable to specific sites, general equations were presented as a first step in refining the analysis. These equations identify the general relationships among the important variables and suggest those areas of concern for which further data are required. If the current model indicates that geomorphic processes (taken together with other geologic changes) may ultimately affect the geologic containment of nuclear waste, further research may be necessary to refine this analysis for application to specific sites.

  14. Beyond Hazards and Disasters--Teaching Students Geoscience by Probing the Underlying Influence of Geology on Human Events.

    ERIC Educational Resources Information Center

    Tewksbury, Barbara J.

    1999-01-01

    Describes a course that explores the ways in which geology can have an underlying influence on human events that is much deeper and more subtle than the distribution of resource wealth and geologic hazards. The course revolves around a series of geological topics that have direct relevance to particular prehistoric, historical, political, or…

  15. Retroactive Event Determination and Its Relativistic Roots

    NASA Astrophysics Data System (ADS)

    Nelson, Sky E.

    2011-11-01

    Quantum theory limits what we are allowed to say about the "true" state of a quantum system if that system is unobserved. But special relativity relies fundamentally on a universal assumption about what a light particle is doing at ALL times, regardless of being observed (namely, traveling at speed c relative to any inertial observer). This constitutes a fundamental conceptual gap between the theories. In resolving this impasse we show that the state of a light particle (and hence space and time) is not objective or continuous. Time dilation and length contraction become infinite for a photon, so light has no "experience" of event separation in space or time (Δt' = 0, Δx' = 0). The principle of simultaneity is applied between an inertial observer and a light particle, such that the relative speed of the two systems is c, and gamma = infinite/undefined. Although light experiences no separation between events, the Lorentz transform Δt' = γ (Δt-ΔLv/c2) implies that the inertial observer experiences a separation between those same events of exactly Δt = ΔL/c, a light-like separation. In other words, although light does not "register" time or space itself, light will always be measured by an inertial observer at a position and time exactly as if it had travelled at speed c continuously through the intervening medium. This fits nicely within the limitations set by quantum mechanics. This result is connected with previous work on retroactive event determination, suggesting the ubiquitous existence of "synchronicity".

  16. Retroactive Event Determination and Its Relativistic Roots

    SciTech Connect

    Nelson, Sky E.

    2011-11-29

    Quantum theory limits what we are allowed to say about the 'true' state of a quantum system if that system is unobserved. But special relativity relies fundamentally on a universal assumption about what a light particle is doing at ALL times, regardless of being observed (namely, traveling at speed c relative to any inertial observer). This constitutes a fundamental conceptual gap between the theories. In resolving this impasse we show that the state of a light particle (and hence space and time) is not objective or continuous. Time dilation and length contraction become infinite for a photon, so light has no 'experience' of event separation in space or time ({Delta}t' = 0, {Delta}x' = 0). The principle of simultaneity is applied between an inertial observer and a light particle, such that the relative speed of the two systems is c, and gamma = infinite/undefined. Although light experiences no separation between events, the Lorentz transform {Delta}t' = {gamma} ({Delta}t-{Delta}Lv/c{sup 2}) implies that the inertial observer experiences a separation between those same events of exactly {Delta}t = {Delta}L/c, a light-like separation. In other words, although light does not 'register' time or space itself, light will always be measured by an inertial observer at a position and time exactly as if it had travelled at speed c continuously through the intervening medium. This fits nicely within the limitations set by quantum mechanics. This result is connected with previous work on retroactive event determination, suggesting the ubiquitous existence of ''synchronicity''.

  17. Minimal geological methane emissions during the Younger Dryas-Preboreal abrupt warming event.

    PubMed

    Petrenko, Vasilii V; Smith, Andrew M; Schaefer, Hinrich; Riedel, Katja; Brook, Edward; Baggenstos, Daniel; Harth, Christina; Hua, Quan; Buizert, Christo; Schilt, Adrian; Fain, Xavier; Mitchell, Logan; Bauska, Thomas; Orsi, Anais; Weiss, Ray F; Severinghaus, Jeffrey P

    2017-08-23

    Methane (CH4) is a powerful greenhouse gas and plays a key part in global atmospheric chemistry. Natural geological emissions (fossil methane vented naturally from marine and terrestrial seeps and mud volcanoes) are thought to contribute around 52 teragrams of methane per year to the global methane source, about 10 per cent of the total, but both bottom-up methods (measuring emissions) and top-down approaches (measuring atmospheric mole fractions and isotopes) for constraining these geological emissions have been associated with large uncertainties. Here we use ice core measurements to quantify the absolute amount of radiocarbon-containing methane ((14)CH4) in the past atmosphere and show that geological methane emissions were no higher than 15.4 teragrams per year (95 per cent confidence), averaged over the abrupt warming event that occurred between the Younger Dryas and Preboreal intervals, approximately 11,600 years ago. Assuming that past geological methane emissions were no lower than today, our results indicate that current estimates of today's natural geological methane emissions (about 52 teragrams per year) are too high and, by extension, that current estimates of anthropogenic fossil methane emissions are too low. Our results also improve on and confirm earlier findings that the rapid increase of about 50 per cent in mole fraction of atmospheric methane at the Younger Dryas-Preboreal event was driven by contemporaneous methane from sources such as wetlands; our findings constrain the contribution from old carbon reservoirs (marine methane hydrates, permafrost and methane trapped under ice) to 19 per cent or less (95 per cent confidence). To the extent that the characteristics of the most recent deglaciation and the Younger Dryas-Preboreal warming are comparable to those of the current anthropogenic warming, our measurements suggest that large future atmospheric releases of methane from old carbon sources are unlikely to occur.

  18. Minimal geological methane emissions during the Younger Dryas-Preboreal abrupt warming event

    NASA Astrophysics Data System (ADS)

    Petrenko, Vasilii V.; Smith, Andrew M.; Schaefer, Hinrich; Riedel, Katja; Brook, Edward; Baggenstos, Daniel; Harth, Christina; Hua, Quan; Buizert, Christo; Schilt, Adrian; Fain, Xavier; Mitchell, Logan; Bauska, Thomas; Orsi, Anais; Weiss, Ray F.; Severinghaus, Jeffrey P.

    2017-08-01

    Methane (CH4) is a powerful greenhouse gas and plays a key part in global atmospheric chemistry. Natural geological emissions (fossil methane vented naturally from marine and terrestrial seeps and mud volcanoes) are thought to contribute around 52 teragrams of methane per year to the global methane source, about 10 per cent of the total, but both bottom-up methods (measuring emissions) and top-down approaches (measuring atmospheric mole fractions and isotopes) for constraining these geological emissions have been associated with large uncertainties. Here we use ice core measurements to quantify the absolute amount of radiocarbon-containing methane (14CH4) in the past atmosphere and show that geological methane emissions were no higher than 15.4 teragrams per year (95 per cent confidence), averaged over the abrupt warming event that occurred between the Younger Dryas and Preboreal intervals, approximately 11,600 years ago. Assuming that past geological methane emissions were no lower than today, our results indicate that current estimates of today’s natural geological methane emissions (about 52 teragrams per year) are too high and, by extension, that current estimates of anthropogenic fossil methane emissions are too low. Our results also improve on and confirm earlier findings that the rapid increase of about 50 per cent in mole fraction of atmospheric methane at the Younger Dryas-Preboreal event was driven by contemporaneous methane from sources such as wetlands; our findings constrain the contribution from old carbon reservoirs (marine methane hydrates, permafrost and methane trapped under ice) to 19 per cent or less (95 per cent confidence). To the extent that the characteristics of the most recent deglaciation and the Younger Dryas-Preboreal warming are comparable to those of the current anthropogenic warming, our measurements suggest that large future atmospheric releases of methane from old carbon sources are unlikely to occur.

  19. 10 CFR 950.22 - Covered event determination.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 4 2012-01-01 2012-01-01 false Covered event determination. 950.22 Section 950.22 Energy... Covered event determination. (a) Completeness review. Upon notification of a covered event from the... with paragraph (c) of this section. (b) Covered Event Determination. The Claims Administrator...

  20. 10 CFR 950.22 - Covered event determination.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 4 2013-01-01 2013-01-01 false Covered event determination. 950.22 Section 950.22 Energy... Covered event determination. (a) Completeness review. Upon notification of a covered event from the... with paragraph (c) of this section. (b) Covered Event Determination. The Claims Administrator...

  1. 10 CFR 950.22 - Covered event determination.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 4 2014-01-01 2014-01-01 false Covered event determination. 950.22 Section 950.22 Energy... Covered event determination. (a) Completeness review. Upon notification of a covered event from the... with paragraph (c) of this section. (b) Covered Event Determination. The Claims Administrator...

  2. Geology

    NASA Technical Reports Server (NTRS)

    Stewart, R. K.; Sabins, F. F., Jr.; Rowan, L. C.; Short, N. M.

    1975-01-01

    Papers from private industry reporting applications of remote sensing to oil and gas exploration were presented. Digitally processed LANDSAT images were successfully employed in several geologic interpretations. A growing interest in digital image processing among the geologic user community was shown. The papers covered a wide geographic range and a wide technical and application range. Topics included: (1) oil and gas exploration, by use of radar and multisensor studies as well as by use of LANDSAT imagery or LANDSAT digital data, (2) mineral exploration, by mapping from LANDSAT and Skylab imagery and by LANDSAT digital processing, (3) geothermal energy studies with Skylab imagery, (4) environmental and engineering geology, by use of radar or LANDSAT and Skylab imagery, (5) regional mapping and interpretation, and digital and spectral methods.

  3. Synergetic events in geological medium and nonlinear features of wave propagation.

    NASA Astrophysics Data System (ADS)

    Hachay, O. A.

    2009-04-01

    Geological medium is an open dynamical system, which is artificially and naturally influenced on different scale levels, which change it's state and which lead to a complicated many ranked hierarchic evolution. That is a topic of the synergetic theory (or science of self organization). The idea of physical meso mechanics which was elaborated by Russian academician Panin V.E., which includes the synergetic approach, is a constructive method for research of the state of heterogenic materials. That result had been obtained for specimens of different materials. In our investigations of time-dependent geological medium in the frame of natural experiments in real rock massive, which are hard man-caused influenced it had been showed, that the dynamics of the state can be revealed by using synergetic approach for hierarchic media. The important role for research of dynamic geological systems play the use of active and passive geophysical monitoring, which can be achieved with use of electromagnetic and seismic fields. As it had been showed by our experience the change of the system on the researched space bases and times can be revealed by parameters, linked with peculiarities of the medium of the second and higher rank. Thus the research of the state dynamics and the events of self organization we can provide with geophysical methods, oriented on the many ranked hierarchic time-dependent model of the medium. For fields of plastic deformation and stresses it had been considered a system of differential equations. The developing theory of modelling and interpretation of geophysical monitoring data must be active guided by the mathematical methods of nonlinear dynamics and control. The developing of that direction can allow us to forecast and prevent catastrophic man-made events (rock bursts). We had elaborated a new approach of forecasting such events using the method of constructing phase portraits using the data of electromagnetic monitoring and detailed seismological

  4. Determination of total mercury in biological and geological samples

    USGS Publications Warehouse

    Crock, James G.

    2005-01-01

    The analytical chemist is faced with several challenges when determining mercury in biological and geological materials. These challenges include widespread mercury contamination, both in the laboratory and the environment, possible losses of mercury during sample preparation and digestion, the wide range of mercury values commonly observed, ranging from the low nanogram per gram or per liter for background areas to hundreds of milligrams per kilogram in contaminated or ore-bearing areas, great matrix diversity, and sample heterogeneity1. These factors can be naturally occurring or anthropogenic, but must be addressed to provide a precise and accurate analysis. Although there are many instrumental methods available for the successful determination of mercury, no one technique will address all problems or all samples all of the time. The approach for the determination of mercury used at the U.S. Geological Survey, Crustal Imaging and Characterization Team, Denver Laboratories, utilizes a suite of complementary instrumental methods when approaching a study requiring mercury analyses. Typically, a study could require the analysis of waters, leachates or selective digestions of solids, vegetation, and biological materials such as tissue, bone, or shell, soils, rocks, sediments, coals, sludges, and(or) ashes. No one digestion or sample preparation method will be suitable for all of these matrices. The digestions typically employed at our laboratories include: (i) a closed-vessel microwave method using nitric acid and hydrogen peroxide, followed by digestion/dilution with a nitric acid/sodium dichromate solution, (ii) a robotic open test-tube digestion with nitric acid and sodium dichromate, (iii) a sealed Teflon? vessel with nitric acid and sodium dichromate, (iv) a sealed glass bottle with nitric acid and sodium dichromate, or (v) open test tube digestion with nitric and sulfuric acids and vanadium pentoxide. The common factor in all these digestions is that they are

  5. 10 CFR 950.32 - Final determination on covered events.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false Final determination on covered events. 950.32 Section 950... Process § 950.32 Final determination on covered events. (a) If the parties reach a Final Determination on Covered Events through mediation, or Summary Binding Decision as set forth in this subpart, the...

  6. 10 CFR 950.32 - Final determination on covered events.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 4 2013-01-01 2013-01-01 false Final determination on covered events. 950.32 Section 950... Process § 950.32 Final determination on covered events. (a) If the parties reach a Final Determination on Covered Events through mediation, or Summary Binding Decision as set forth in this subpart, the...

  7. 10 CFR 950.32 - Final determination on covered events.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 4 2014-01-01 2014-01-01 false Final determination on covered events. 950.32 Section 950... Process § 950.32 Final determination on covered events. (a) If the parties reach a Final Determination on Covered Events through mediation, or Summary Binding Decision as set forth in this subpart, the...

  8. 10 CFR 950.32 - Final determination on covered events.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 4 2012-01-01 2012-01-01 false Final determination on covered events. 950.32 Section 950... Process § 950.32 Final determination on covered events. (a) If the parties reach a Final Determination on Covered Events through mediation, or Summary Binding Decision as set forth in this subpart, the...

  9. Determining resistivity of a geological formation using circuitry located within a borehole casing

    DOEpatents

    Vail III, William Banning

    2006-01-17

    Geological formation resistivity is determined. Circuitry is located within the borehole casing that is adjacent to the geological formation. The circuitry can measure one or more voltages across two or more voltage measurement electrodes associated with the borehole casing. The measured voltages are used by a processor to determine the resistivity of the geological formation. A common mode signal can also be reduced using the circuitry.

  10. Current Events via Electronic Media: An Instructional Tool in a General Education Geology Course

    NASA Astrophysics Data System (ADS)

    Flood, T. P.

    2008-12-01

    St. Norbert College (SNC) is a liberal arts college in the Green Bay Metropolitan area with an enrollment of approximately 2100 students. All students are required to take one science course with a laboratory component as part of the general education program. Approximately 40% of all SNC students take introductory geology. Class size for this course is approximately 35 students. Each faculty member teaches one section per semester in a smart classroom A synthesis of current events via electronic media is an excellent pedagogical tool for the introductory geology course. An on-going informal survey of my introductory geology class indicates that between 75- 85% of all students in the class, mostly freshman and sophomores, do not follow the news on a regular basis in any format, i.e. print, internet, or television. Consequently, most are unaware of current scientific topics, events, trends, and relevancy. To address this issue, and develop a positive habit of the mind, a technique called In-the-News-Making-News (INMN) is employed. Each class period begins with a scientifically-related (mostly geology) online news article displayed on an overhead screen. The articles are drawn from a variety of sources that include international sites such as the BBC and CBC; national sites such as PBS, New York Times, and CNN; and local sites such as the Milwaukee Journal Sentinel and the Green Bay Press Gazette. After perusing the article, additional information is often acquired by "Google" to help supplement and clarify the original article. An interactive discussion follows. Topics that are typically covered include: global climate change, basic scientific and technological discoveries, paleontology/evolution, natural disasters, mineral/ energy/ water resources, funding for science, space exploration, and other. Ancillary areas that are often touched on in the conversation include ethics, politics, economics, philosophy, education, geography, culture, or other. INMN addresses

  11. 10 CFR 950.22 - Covered event determination.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false Covered event determination. 950.22 Section 950.22 Energy DEPARTMENT OF ENERGY STANDBY SUPPORT FOR CERTAIN NUCLEAR PLANT DELAYS Claims Administration Process § 950.22 Covered event determination. (a) Completeness review. Upon notification of a covered event from the...

  12. 10 CFR 950.22 - Covered event determination.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 4 2011-01-01 2011-01-01 false Covered event determination. 950.22 Section 950.22 Energy DEPARTMENT OF ENERGY STANDBY SUPPORT FOR CERTAIN NUCLEAR PLANT DELAYS Claims Administration Process § 950.22 Covered event determination. (a) Completeness review. Upon notification of a covered event from the...

  13. The role of climatic and geological events in generating diversity in Ethiopian grass frogs (genus Ptychadena)

    PubMed Central

    Colston, Timothy J.

    2017-01-01

    Ethiopia is a world biodiversity hotspot and harbours levels of biotic endemism unmatched in the Horn of Africa, largely due to topographic—and thus habitat—complexity, which results from a very active geological and climatic history. Among Ethiopian vertebrate fauna, amphibians harbour the highest levels of endemism, making amphibians a compelling system for the exploration of the impacts of Ethiopia's complex abiotic history on biotic diversification. Grass frogs of the genus Ptychadena are notably diverse in Ethiopia, where they have undergone an evolutionary radiation. We used molecular data and expanded taxon sampling to test for cryptic diversity and to explore diversification patterns in both the highland radiation and two widespread lowland Ptychadena. Species delimitation results support the presence of nine highland species and four lowland species in our dataset, and divergence dating suggests that both geologic events and climatic fluctuations played a complex and confounded role in the diversification of Ptychadena in Ethiopia. We rectify the taxonomy of the endemic P. neumanni species complex, elevating one formally synonymized name and describing three novel taxa. Finally, we describe two novel lowland Ptychadena species that occur in Ethiopia and may be more broadly distributed. PMID:28878964

  14. The role of climatic and geological events in generating diversity in Ethiopian grass frogs (genus Ptychadena).

    PubMed

    Smith, Megan L; Noonan, Brice P; Colston, Timothy J

    2017-08-01

    Ethiopia is a world biodiversity hotspot and harbours levels of biotic endemism unmatched in the Horn of Africa, largely due to topographic-and thus habitat-complexity, which results from a very active geological and climatic history. Among Ethiopian vertebrate fauna, amphibians harbour the highest levels of endemism, making amphibians a compelling system for the exploration of the impacts of Ethiopia's complex abiotic history on biotic diversification. Grass frogs of the genus Ptychadena are notably diverse in Ethiopia, where they have undergone an evolutionary radiation. We used molecular data and expanded taxon sampling to test for cryptic diversity and to explore diversification patterns in both the highland radiation and two widespread lowland Ptychadena. Species delimitation results support the presence of nine highland species and four lowland species in our dataset, and divergence dating suggests that both geologic events and climatic fluctuations played a complex and confounded role in the diversification of Ptychadena in Ethiopia. We rectify the taxonomy of the endemic P. neumanni species complex, elevating one formally synonymized name and describing three novel taxa. Finally, we describe two novel lowland Ptychadena species that occur in Ethiopia and may be more broadly distributed.

  15. Determinants of Adverse Events in Vascular Surgery

    PubMed Central

    Hernandez-Boussard, Tina; McDonald, Kathryn; Morton, John; Dalman, Ron L; Bech, Fritz R

    2016-01-01

    Background Patient safety is a national priority. Patient Safety Indicators (PSIs) monitor potential adverse events during hospital stays. Surgical specialty PSI benchmarks do not exist, which are needed to account for differences in the range of procedures performed, reasons for the procedure, and differences in patient characteristics. A comprehensive profile of adverse events in vascular surgery was created. Study Design The Nationwide Inpatient Sample was queried for 8 vascular procedures using ICD-9-CM codes from 2005–2009. Factors associated with PSI development were evaluated in univariate and multivariate analyses. Results A total of 1,412,703 patients underwent a vascular procedure and 5.2% developed a PSI. PSIs were more frequent in female, non-white patients with public payers (p<.01). Patients at mid and low volume hospitals had greater odds of developing a PSI (Odds Ratio [OR], 1.17; 95% Confidence Interval [CI], 1.10–1.23 and OR, 1.69; CI, 1.53–1.87). Amputations had highest PSI risk-adjusted rate (RAR) and carotid endarterectomy and endovascular abdominal aortic aneurysm (AAA) repair had lower RAR (p<.0001). PSI RAR increased linearly by severity of patient indication: claudicants (OR, 0.40, CI, 0.35–0.46), rest pain patients (OR, 0.78, CI 0.69–0.90), ulcer (OR: 1.20, CI: 1.07–1.34) and gangrene patients (OR:1.85, CI: 1.66–2.06). Conclusions Patient safety events in vascular surgery were high and varied by procedure, with amputations and open AAA having substantially more potential adverse events. PSIs were associated with black race, public payer, and procedure indication. It is important to note the overall higher rates of PSIs occurring in vascular patients and appropriately adjust benchmarks for this surgical specialty. PMID:22425449

  16. 10 CFR 950.32 - Final determination on covered events.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 4 2011-01-01 2011-01-01 false Final determination on covered events. 950.32 Section 950.32 Energy DEPARTMENT OF ENERGY STANDBY SUPPORT FOR CERTAIN NUCLEAR PLANT DELAYS Dispute Resolution Process § 950.32 Final determination on covered events. (a) If the parties reach a Final Determination on...

  17. Determination of precipitating events in the suicide of psychiatric patients.

    PubMed

    Maltsberger, John T; Hendin, Herbert; Haas, Ann Pollinger; Lipschitz, Alan

    2003-01-01

    Data from therapists who were treating patients when they killed themselves were used to provide information about precipitating events that was missing from accounts obtained from suicide victims' relatives and friends. Among 26 patient suicides studied, the therapists identified a precipitating event in 25 cases; in 19 of these, supporting evidence linked the identified event to the suicide. A schema was developed that identifies nine types of evidence provided by therapists in determining that an event precipitated the suicide. Use of the schema is likely to improve accurate identification of events that precipitate patient suicides, and distinguish them from unrelated coterminous events or suicide risk factors.

  18. A Methodology for Determining Training Event Cost.

    DTIC Science & Technology

    1983-06-01

    control scheme, the Jaehne model , is also presented. A~ model based on regression techniques is developed for determining the cost of battalion...CLASIICATION OF THIS PAGE tWbm pD E~eMQ Item 20 (Contd) are drawn on the applicability and promise of the model . This thesis presents an additional training...categories of training and the develcpuent of equiptent oferating cost factors. An additional training resource ccntrol scheme, the Jaehne model , is also

  19. The impact of Damaging Hydro Geological events on people in a Mediterranean region

    NASA Astrophysics Data System (ADS)

    Petrucci, O.; Pasqua, A. A.

    2012-04-01

    Bad weather periods are a source of multiple hazards, because they can trigger several types of damaging phenomena which may cause different types of impacts on several natural and manmade elements in a wide range of circumstances. The whole of all the phenomena triggered by bad weather periods have been defined as Damaging Hydro Geological Events (DHE). Phenomena which occur during DHEs can be roughly sorted in some main groups: landslides, floods, erosion processes and sea storms. Each type of phenomenon is characterized by a proper dynamic and, according to the social and economic framework in which it develops, can cause different impacts. Despite during bad weather periods all these phenomena occur at the same time (or in a short while), often strongly amplifying damage and hinting emergency management actions, the studies available in literature tend to analyse each type of phenomenon (and its impact) separately, thus supplying a fragmentary framework of the effects. In the present work, basing on a dataset concerning effects of DHEs in Calabria (southern Italy), a classification of the effects on people affected by the different types of triggered phenomena is attempted. The results is a classification of main circumstances during which the different types of phenomenon triggered can hit people. This kind of result can be useful in education programs for people living in risk prone areas, in order promote more conscious behaviours during DHEs and to avoid unnecessary risk-taking behaviour.

  20. Suspended sediment from different geological sources in a watershed determined by natural radionuclides

    NASA Astrophysics Data System (ADS)

    Mizugaki, S.; Abe, T.; Murakami, Y.; Kubo, M.; Maruyama, M.; Hamamoto, S.

    2011-12-01

    The geological setting is essential for occurrence of slope failure and landslide so that the geology may control the suspended sediment yield with different magnitude. In the Saru River watershed of central Hokkaido, northern Japan, the typhoon Etau in August 2003 brought heavy rainfall, causing the slope failure and landslide across the areas of various geologies and the highest sediment yield since 1960s. Prolonged sediment runoff has caused the serious problems in association with turbid water, sedimentation in the reservoir, and their impacts on fishery and ecology downstream. To clarify the suspended sediment sources within the Nukabira River watershed, a tributary of Saru River, hydrological monitoring of discharge and turbidity and fingerprinting technique using natural radionuclide were conducted during a heavy rainfall event in August 2010. GIS analysis for slope failure and landslide areas was also conducted to investigate the distribution of potential suspended sediment sources. The activity of radionuclides, including U-series, Th-series, cesium-137 and potassium-40 were determined by gamma ray spectrometry. Statistical analysis showed the best composite fingerprints of Pb-212, Ac-228 and K-40 to classify the suspended sediment sources into six geological units, which were sedimentary rock, plutonic rock, metamorphic rock and three types of cretaceous accretionary complex consist of sedimentary rock, basalt block and volcanic rock. The contribution of source group to suspended sediment was calculated according to the assumption that the Mahalanobis distance in tracer properties between sources and suspended sediment can represent relative contribution of the source. During the rainfall event on August 11, 2011, dominant source of suspended sediment was found to be the areas consist of metamorphic rock (31%), sedimentary rock (30%) and accretionary sedimentary rock (24%). GIS analysis showed the spatial distribution of slope failure and landslide within

  1. Determination of the number of ψ' events at BESIII

    NASA Astrophysics Data System (ADS)

    Ablikim, M.; N. Achasov, M.; Albayrak, O.; J. Ambrose, D.; F. An, F.; Q., An; Z. Bai, J.; Ban, Y.; Becker, J.; V. Bennett, J.; Berger, N.; Bertani, M.; M. Bian, J.; Boger, E.; Bondarenko, O.; Boyko, I.; A. Briere, R.; Bytev, V.; Cai, X.; Cakir, O.; Calcaterra, A.; F. Cao, G.; A. Cetin, S.; F. Chang, J.; Chelkov, G.; G., Chen; S. Chen, H.; C. Chen, J.; L. Chen, M.; J. Chen, S.; X., Chen; B. Chen, Y.; P. Cheng, H.; P. Chu, Y.; Cronin-Hennessy, D.; L. Dai, H.; P. Dai, J.; Dedovich, D.; Y. Deng, Z.; Denig, A.; Denysenko, I.; Destefanis, M.; M. Ding, W.; Y., Ding; Y. Dong, L.; Y. Dong, M.; X. Du, S.; J., Fang; S. Fang, S.; Fava, L.; Q. Feng, C.; B. Ferroli, R.; Friedel, P.; D. Fu, C.; Gao, Y.; C., Geng; Goetzen, K.; X. Gong, W.; Gradl, W.; Greco, M.; H. Gu, M.; T. Gu, Y.; H. Guan, Y.; Q. Guo, A.; B. Guo, L.; T., Guo; P. Guo, Y.; L. Han, Y.; A. Harris, F.; L. He, K.; M., He; Y. He, Z.; Held, T.; K. Heng, Y.; L. Hou, Z.; C., Hu; M. Hu, H.; F. Hu, J.; T., Hu; M. Huang, G.; S. Huang, G.; S. Huang, J.; L., Huang; T. Huang, X.; Y., Huang; P. Huang, Y.; Hussain, T.; S. Ji, C.; Q., Ji; P. Ji, Q.; B. Ji, X.; L. Ji, X.; L. Jiang, L.; S. Jiang, X.; B. Jiao, J.; Jiao, Z.; P. Jin, D.; S., Jin; F. Jing, F.; Kalantar-Nayestanaki, N.; Kavatsyuk, M.; Kopf, B.; Kornicer, M.; Kuehn, W.; Lai, W.; S. Lange, J.; Leyhe, M.; H. Li, C.; Cheng, Li; Cui, Li; M. Li, D.; F., Li; G., Li; B. Li, H.; C. Li, J.; K., Li; Lei, Li; J. Li, Q.; L. Li, S.; D. Li, W.; G. Li, W.; L. Li, X.; N. Li, X.; Q. Li, X.; R. Li, X.; B. Li, Z.; H., Liang; F. Liang, Y.; T. Liang, Y.; R. Liao, G.; T. Liao, X.; Lin(Lin, D.; J. Liu, B.; L. Liu, C.; X. Liu, C.; H. Liu, F.; Fang, Liu; Feng, Liu; H., Liu; B. Liu, H.; H. Liu, H.; M. Liu, H.; W. Liu, H.; P. Liu, J.; K., Liu; Y. Liu, K.; Kai, Liu; L. Liu, P.; Q., Liu; B. Liu, S.; X., Liu; B. Liu, Y.; A. Liu, Z.; Zhiqiang, Liu; Zhiqing, Liu; Loehner, H.; R. Lu, G.; J. Lu, H.; G. Lu, J.; W. Lu, Q.; R. Lu, X.; P. Lu, Y.; L. Luo, C.; X. Luo, M.; Luo, T.; L. Luo, X.; Lv, M.; L. Ma, C.; C. Ma, F.; L. Ma, H.; M. Ma, Q.; Ma, S.; Ma, T.; Y. Ma, X.; E. Maas, F.; Maggiora, M.; A. Malik, Q.; J. Mao, Y.; P. Mao, Z.; G. Messchendorp, J.; J., Min; J. Min, T.; E. Mitchell, R.; H. Mo, X.; C. Morales, Morales; Yu. Muchnoi, N.; Muramatsu, H.; Nefedov, Y.; Nicholson, C.; B. Nikolaev, I.; Z., Ning; L. Olsen, S.; Ouyang, Q.; Pacetti, S.; W. Park, J.; Pelizaeus, M.; P. Peng, H.; Peters, K.; L. Ping, J.; G. Ping, R.; Poling, R.; Prencipe, E.; M., Qi; Qian, S.; F. Qiao, C.; Q. Qin, L.; S. Qin, X.; Y., Qin; H. Qin, Z.; F. Qiu, J.; H. Rashid, K.; G., Rong; D. Ruan, X.; Sarantsev, A.; D. Schaefer, B.; Shao, M.; P. Shen, C.; Y. Shen, X.; Y. Sheng, H.; R. Shepherd, M.; Y. Song, X.; Spataro, S.; Spruck, B.; H. Sun, D.; X. Sun, G.; F. Sun, J.; S. Sun, S.; J. Sun, Y.; Z. Sun, Y.; J. Sun, Z.; T. Sun, Z.; J. Tang, C.; Tang, X.; Tapan, I.; H. Thorndike, E.; Toth, D.; Ullrich, M.; S. Varner, G.; Q. Wang, B.; D., Wang; Y. Wang, D.; K., Wang; L. Wang, L.; S. Wang, L.; M., Wang; P., Wang; L. Wang, P.; J. Wang, Q.; G. Wang, S.; F. Wang, X.; L. Wang, X.; F. Wang, Y.; Z., Wang; G. Wang, Z.; Y. Wang, Z.; H. Wei, D.; B. Wei, J.; Weidenkaff, P.; G. Wen, Q.; P. Wen, S.; M., Werner; Wiedner, U.; H. Wu, L.; N., Wu; X. Wu, S.; W., Wu; Z., Wu; G. Xia, L.; X Xia, Y.; J. Xiao, Z.; G. Xie, Y.; L. Xiu, Q.; F. Xu, G.; M. Xu, G.; J. Xu, Q.; N. Xu, Q.; P. Xu, X.; R. Xu, Z.; Xue, F.; Xue, Z.; L., Yan; B. Yan, W.; H. Yan, Y.; X. Yang, H.; Y., Yang; X. Yang, Y.; Ye, H.; Ye, M.; H. Ye, M.; X. Yu, B.; X. Yu, C.; W. Yu, H.; S. Yu, J.; P. Yu, S.; Z. Yuan, C.; Y., Yuan; A. Zafar, A.; Zallo, A.; Zeng, Y.; X. Zhang, B.; Y. Zhang, B.; Zhang, C.; C. Zhang, C.; H. Zhang, D.; H. Zhang, H.; Y. Zhang, H.; Q. Zhang, J.; W. Zhang, J.; Y. Zhang, J.; Z. Zhang, J.; Lili, Zhang; Zhang, R.; H. Zhang, S.; J. Zhang, X.; Y. Zhang, X.; Zhang, Y.; H. Zhang, Y.; P. Zhang, Z.; Y. Zhang, Z.; Zhenghao, Zhang; Zhao, G.; S. Zhao, H.; W. Zhao, J.; X. Zhao, K.; Lei, Zhao; Ling, Zhao; G. Zhao, M.; Zhao, Q.; Z. Zhao, Q.; J. Zhao, S.; C. Zhao, T.; B. Zhao, Y.; G. Zhao, Z.; Zhemchugov, A.; B., Zheng; P. Zheng, J.; H. Zheng, Y.; B., Zhong; Z., Zhong; L., Zhou; K. Zhou, X.; R. Zhou, X.; Zhu, C.; Zhu, K.; J. Zhu, K.; H. Zhu, S.; L. Zhu, X.; C. Zhu, Y.; M. Zhu, Y.; S. Zhu, Y.; A. Zhu, Z.; J., Zhuang; S. Zou, B.; H. Zou, J.

    2013-06-01

    The number of ψ' events accumulated by the BESIII experiment from March 3 through April 14, 2009, is determined by counting inclusive hadronic events. The result is 106.41×(1.00±0.81%)×106. The error is systematic dominant; the statistical error is negligible.

  2. Scale Determinants of Fiscal Investment in Geological Exploration: Evidence from China

    PubMed Central

    Lu, Linna; Lei, Yalin

    2013-01-01

    With the continued growth in demand for mineral resources and China's efforts in increasing investment in geological prospecting, fiscal investment in geological exploration becomes a research hotspot. This paper examines the yearly relationship among fiscal investment in geological exploration of the current term, that of the last term and prices of mining rights over the period 1999–2009. Hines and Catephores' investment acceleration model is applied to describe the scale determinants of fiscal investment in geological exploration which are value-added of mining rights, value of mining rights and fiscal investment in the last term. The results indicate that when value-added of mining rights, value of mining rights or fiscal investment in the last term moves at 1 unit, fiscal investment in the current term will move 0.381, 1.094 or 0.907 units respectively. In order to determine the scale of fiscal investment in geological exploration for the current year, the Chinese government should take fiscal investment in geological exploration for the last year and the capital stock of the previous investments into account. In practice, combination of government fiscal investment in geological exploration with its performance evaluation can create a virtuous circle of capital management mechanism. PMID:24204652

  3. Scale determinants of fiscal investment in geological exploration: evidence from China.

    PubMed

    Lu, Linna; Lei, Yalin

    2013-01-01

    With the continued growth in demand for mineral resources and China's efforts in increasing investment in geological prospecting, fiscal investment in geological exploration becomes a research hotspot. This paper examines the yearly relationship among fiscal investment in geological exploration of the current term, that of the last term and prices of mining rights over the period 1999-2009. Hines and Catephores' investment acceleration model is applied to describe the scale determinants of fiscal investment in geological exploration which are value-added of mining rights, value of mining rights and fiscal investment in the last term. The results indicate that when value-added of mining rights, value of mining rights or fiscal investment in the last term moves at 1 unit, fiscal investment in the current term will move 0.381, 1.094 or 0.907 units respectively. In order to determine the scale of fiscal investment in geological exploration for the current year, the Chinese government should take fiscal investment in geological exploration for the last year and the capital stock of the previous investments into account. In practice, combination of government fiscal investment in geological exploration with its performance evaluation can create a virtuous circle of capital management mechanism.

  4. An ion-selective electrode method for determination of chlorine in geological materials

    USGS Publications Warehouse

    Aruscavage, P. J.; Campbell, E.Y.

    1983-01-01

    A method is presented for the determination of chlorine in geological materials, in which a chloride-selective ion electrode is used after decomposition of the sample with hydrofluoric acid and separation of chlorine in a gas-diffusion cell. Data are presented for 30 geological standard materials. The relative standard deviation of the method is estimated to be better than 8% for amounts of chloride of 10 ??g and greater. ?? 1983.

  5. Localization of microseismic events and determination of source parameters

    NASA Astrophysics Data System (ADS)

    Mokshin, E. V.; Berezhnoi, D. V.

    2016-11-01

    We examine the problem of localization determining and a microseismic moment tensor of single microseismic event in the presence of strongly correlated noise. This is a typical problem occurring in monitoring of microseismic events from a daylight surface under conditions of a producing field or surface monitoring of hydraulic fracturing. We offer the solution to this problem based on the method of maximum likelihood. The article presents of decision of this problem and the results of numerical experiments. We discuss some features and problems of the proposed approach and estimate the required computing resources. We develop the problem of determination direction of fracture propagation from microseismic event.

  6. Geologic events coupled with Pleistocene climatic oscillations drove genetic variation of Omei treefrog (Rhacophorus omeimontis) in southern China.

    PubMed

    Li, Jun; Zhao, Mian; Wei, Shichao; Luo, Zhenhua; Wu, Hua

    2015-12-21

    Pleistocene climatic oscillations and historical geological events may both influence current patterns of genetic variation, and the species in southern China that faced unique climatic and topographical events have complex evolutionary histories. However, the relative contributions of climatic oscillations and geographical events to the genetic variation of these species remain undetermined. To investigate patterns of genetic variation and to test the hypotheses about the factors that shaped the distribution of this genetic variation in species of southern China, mitochondrial genes (cytochrome b and NADH dehydrogenase subunit 2) and nine microsatellite loci of the Omei tree frog (Rhacophorus omeimontis) were amplified in this study. The genetic diversity in the populations of R. omeimontis was high. The phylogenetic trees reconstructed from the mitochondrial DNA (mtDNA) haplotypes and the Bayesian genetic clustering analysis based on microsatellite data both revealed that all populations were divided into three lineages (SC, HG and YN). The two most recent splitting events among the lineages coincided with recent geological events (including the intense uplift of the Qinghai-Tibet Plateau, QTP and the subsequent movements of the Yun-Gui Plateau, YGP) and the Pleistocene glaciations. Significant expansion signals were not detected in mismatch analyses or neutrality tests. And the effective population size of each lineage was stable during the Pleistocene. Based on the results of this study, complex geological events (the recent dramatic uplift of the QTP and the subsequent movements of the YGP) and the Pleistocene glaciations were apparent drivers of the rapid divergence of the R. omeimontis lineages. Each diverged lineages survived in situ with limited gene exchanges, and the stable demographics of lineages indicate that the Pleistocene climatic oscillations were inconsequential for this species. The analysis of genetic variation in populations of R. omeimontis

  7. Event Coverage Detection and Event Source Determination in Underwater Wireless Sensor Networks.

    PubMed

    Zhou, Zhangbing; Xing, Riliang; Duan, Yucong; Zhu, Yueqin; Xiang, Jianming

    2015-12-15

    With the advent of the Internet of Underwater Things, smart things are deployed in the ocean space and establish underwater wireless sensor networks for the monitoring of vast and dynamic underwater environments. When events are found to have possibly occurred, accurate event coverage should be detected, and potential event sources should be determined for the enactment of prompt and proper responses. To address this challenge, a technique that detects event coverage and determines event sources is developed in this article. Specifically, the occurrence of possible events corresponds to a set of neighboring sensor nodes whose sensory data may deviate from a normal sensing range in a collective fashion. An appropriate sensor node is selected as the relay node for gathering and routing sensory data to sink node(s). When sensory data are collected at sink node(s), the event coverage is detected and represented as a weighted graph, where the vertices in this graph correspond to sensor nodes and the weight specified upon the edges reflects the extent of sensory data deviating from a normal sensing range. Event sources are determined, which correspond to the barycenters in this graph. The results of the experiments show that our technique is more energy efficient, especially when the network topology is relatively steady.

  8. Event Coverage Detection and Event Source Determination in Underwater Wireless Sensor Networks

    PubMed Central

    Zhou, Zhangbing; Xing, Riliang; Duan, Yucong; Zhu, Yueqin; Xiang, Jianming

    2015-01-01

    With the advent of the Internet of Underwater Things, smart things are deployed in the ocean space and establish underwater wireless sensor networks for the monitoring of vast and dynamic underwater environments. When events are found to have possibly occurred, accurate event coverage should be detected, and potential event sources should be determined for the enactment of prompt and proper responses. To address this challenge, a technique that detects event coverage and determines event sources is developed in this article. Specifically, the occurrence of possible events corresponds to a set of neighboring sensor nodes whose sensory data may deviate from a normal sensing range in a collective fashion. An appropriate sensor node is selected as the relay node for gathering and routing sensory data to sink node(s). When sensory data are collected at sink node(s), the event coverage is detected and represented as a weighted graph, where the vertices in this graph correspond to sensor nodes and the weight specified upon the edges reflects the extent of sensory data deviating from a normal sensing range. Event sources are determined, which correspond to the barycenters in this graph. The results of the experiments show that our technique is more energy efficient, especially when the network topology is relatively steady. PMID:26694394

  9. 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)

  10. 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)

  11. A large-scale phylogeny of Synodontis (Mochokidae, Siluriformes) reveals the influence of geological events on continental diversity during the Cenozoic.

    PubMed

    Pinton, Aurélie; Agnèse, Jean-François; Paugy, Didier; Otero, Olga

    2013-03-01

    To explain the spatial variability of fish taxa at a large scale, two alternative proposals are usually evoked. In recent years, the debate has centred on the relative roles of present and historical processes in shaping biodiversity patterns. In Africa, attempts to understand the processes that determine the large scale distribution of fishes and exploration of historical contingencies have been under-investigated given that most of the phylogenetic studies focus on the history of the Great Lakes. Here, we explore phylogeographic events in the evolutionary history of Synodontis (Mohokidae, Siluriformes) over Africa during the Cenozoic focusing on the putative role of historical processes. We discuss how known geological events together with hydrographical changes contributed to shape Synodontis biogeographical history. Synodontis was chosen on the basis of its high diversity and distribution in Africa: it consists of approximately 120 species that are widely distributed in all hydrographic basins except the Maghreb and South Africa. We propose the most comprehensive phylogeny of this catfish genus. Our results provide support for the 'hydrogeological' hypothesis, which proposes that palaeohydrological changes linked with the geological context may have been the cause of diversification of freshwater fish deep in the Tertiary. More precisely, the two main geological structures that participated to shape the hydrographical network in Africa, namely the Central African Shear zone and the East African rift system, appear as strong drivers of Synodontis diversification and evolution. Copyright © 2012 Elsevier Inc. All rights reserved.

  12. Learning about geological events in Vendée (west coast of France)

    NASA Astrophysics Data System (ADS)

    Bretaudeau, Florence; Lavigne, Bruno

    2015-04-01

    Our 70 pupils, aged from 17 to 18 had discovered an area of the west coast of France : Vendée. We studied rocks in order to tell the geological story of this area. Several characteristics were looked at : sedimentary and metamorphics rocks, minerals, fault, folding, unconformability... We took advantage of this geological journey to look at biodiversity in different ecosystems : rocky coast, dune, wood.

  13. Martian Dunite NWA 2737: Petrographic Constraints on Geological History, Shock Events, and Olivine Color

    SciTech Connect

    Treiman,A.; Dyar, M.; McCanta, M.; Noble, S.; Pieters, C.

    2007-01-01

    Meteorite Northwest Africa (NWA) 2737 is the second known chassignite, an olivine-rich igneous rock with mineral compositions and isotopic ratios that suggest it formed on Mars. NWA 2737 consists of ?85% vol. olivine (Mg, molar Mg/(Mg + Fe), of 78.3 {+-} 0.4%), which is notable because it is black in hand sample and brown in thin section. Other minerals include chromite, pyroxenes (augite, pigeonite, orthopyroxene), and diaplectic glass of alkali-feldspar composition. Aqueous alteration is minimal and appears only as slight dissolution of glass. NWA 2737 formed by accumulation of olivine and chromite from a basaltic magma; the other minerals represent magma trapped among the cumulus grains. Minerals are compositionally homogeneous, consistent with chemical equilibration in late and postigneous cooling. Two-pyroxene thermometry gives equilibration temperatures 1150 C, implying a significant time spent at the basalt solidus. Olivine-spinel-pyroxene equilibria give ?825 C (possibly the T of mesostasis crystallization) at an oxidation state of QMF-1. This oxidation state is consistent with low Fe3+ in olivine (determined by EMP, Moessbauer spectra, and synchrotron micro-XANES spectroscopy) and with {approx}10% of the iron in pyroxene being Fe3+. NWA 2737 experienced two shock events. The first shock, to stage S5-S6, affected the olivine by producing in it planar deformation features, intense mosaicism and lattice strain, and abundant droplets of iron-nickel metal, 5-15 nm in diameter. At this stage the olivine became deeply colored, i.e., strongly absorbing at visible and near-infrared (NIR) wavelengths. This shock event and its thermal pulse probably occurred at {approx}170 Ma, the Ar-Ar age of NWA 2737. The colored olivine is cut by ribbons of coarser, uncolored olivine with long axes along [100] and shorter axes on {l_brace}021{r_brace} planes: These are consistent with the easy slip law for olivine [100]{l_brace}021{r_brace}, which is activated at moderate strain

  14. Volcano!: An Event-Based Science Module. Teacher's Guide. Geology Module.

    ERIC Educational Resources Information Center

    Wright, Russell G.

    This book is designed for middle school earth science teachers to help their students learn scientific literacy through event-based science. Unlike traditional curricula, the event-based earth science module is a student-centered, interdisciplinary, inquiry-oriented program that emphasizes cooperative learning, teamwork, independent research,…

  15. Volcano!: An Event-Based Science Module. Student Edition. Geology Module.

    ERIC Educational Resources Information Center

    Wright, Russell G.

    This book is designed for middle school students to learn scientific literacy through event-based science. Unlike traditional curricula, the event-based earth science module is a student-centered, interdisciplinary, inquiry-oriented program that emphasizes cooperative learning, teamwork, independent research, hands-on investigations, and…

  16. Gold Rush!: An Event-Based Science Module. Teacher's Guide. Geology Module.

    ERIC Educational Resources Information Center

    Wright, Russell G.

    This book is designed for middle school earth science or general science teachers to help their students learn scientific literacy through event-based science. Unlike traditional curricula, the event- based earth science module is a student-centered, interdisciplinary, inquiry-oriented program that emphasizes cooperative learning, teamwork,…

  17. Volcano!: An Event-Based Science Module. Teacher's Guide. Geology Module.

    ERIC Educational Resources Information Center

    Wright, Russell G.

    This book is designed for middle school earth science teachers to help their students learn scientific literacy through event-based science. Unlike traditional curricula, the event-based earth science module is a student-centered, interdisciplinary, inquiry-oriented program that emphasizes cooperative learning, teamwork, independent research,…

  18. Gold Rush!: An Event-Based Science Module. Teacher's Guide. Geology Module.

    ERIC Educational Resources Information Center

    Wright, Russell G.

    This book is designed for middle school earth science or general science teachers to help their students learn scientific literacy through event-based science. Unlike traditional curricula, the event- based earth science module is a student-centered, interdisciplinary, inquiry-oriented program that emphasizes cooperative learning, teamwork,…

  19. Volcano!: An Event-Based Science Module. Student Edition. Geology Module.

    ERIC Educational Resources Information Center

    Wright, Russell G.

    This book is designed for middle school students to learn scientific literacy through event-based science. Unlike traditional curricula, the event-based earth science module is a student-centered, interdisciplinary, inquiry-oriented program that emphasizes cooperative learning, teamwork, independent research, hands-on investigations, and…

  20. Geological record of meltwater events at Qinghai Lake, China from the past 40 ka

    NASA Astrophysics Data System (ADS)

    Zhou, Weijian; Liu, Taibei; Wang, Hao; An, Zhisheng; Cheng, Peng; Zhu, Yizhi; Burr, G. S.

    2016-10-01

    We report here on a previously unpublished sediment core from Qinghai Lake, China, that preserves a continuous record of sedimentation for the past 40 ka. A striking feature of the record is a set of distinct meltwater events recorded at 35, 19 and 14 ka respectively. These events are manifest as distinct pulses of relatively old organic radiocarbon in the sediments. We interpret these as a signal of glacial melting in the Qinghai Lake watershed. The meltwater signals are closely correlated to temperature and precipitation records associated with deglaciation. The events at 19 ka and 14 ka correspond to well-established high latitude Melt Water Pulse (MWP) events during Marine Isotope Stage (MIS) 2, and the 35 ka event corresponds to a period of pervasive high lake levels in western China during late MIS 3. We interpret these anomalous dates as the result of relatively old carbon that was destabilized by the glaciers, and released into the lake as the glaciers melted. The data indicate that this process takes thousands of years. We expect that the approach employed here to identify these events is generally applicable to any lake system with a significant glacial meltwater component.

  1. The Tsunami Geology of the Bay of Bengal Shores and the Predecessors of the 2004 Indian Ocean Event

    NASA Astrophysics Data System (ADS)

    Rajendran, C.; Rajendran, K.; Seshachalam, S.; Andrade, V.

    2010-12-01

    The 2004 Aceh-Andaman earthquake exceeded the known Indian Ocean precedents by its 1,300-km long fault rupture and the height and reach of its tsunami. Literature of the ancient Chola dynasty (AD 9-11 centuries) of south India and the archeological excavations allude to a sea flood that crippled the historic port at Kaveripattinam, a trading hub for Southeast Asia. Here, we combine a variety of data from the rupture zone as well as the distant shores to build a tsunami history of the Bay of Bengal. A compelling set of geological proxies of possible tsunami inundation include boulder beds of Car Nicobar Island in the south and the East Island in the northernmost Andaman, a subsided fossil mangrove forest near Port Blair and a washover sedimentation identified in the Kaveripattinam coast of Tamil Nadu, south India. We have developed an extensive chronology for these geological proxies, and we analyze them in conjunction with the historical information culled from different sources for major sea surges along the Bay of Bengal shores. The age data and the depositional characteristics of these geological proxies suggest four major tsunamis in the last 2000 years in the Bay of Bengal, including the 1881 Car Nicobar tsunami. Among these, the evidence for the event of 800-1200 cal yr BP is fairly well represented on both sides of the Bay of Bengal shores. Thus, we surmise that the 800-1000-year old tsunami mimics the transoceanic reach of the 2004 Indian Ocean and the age constraints also agree with the sea surge during the Chola period. We also obtained clues for a possible medieval tsunami from the islands occurred probably a few hundred years after the Chola tsunami, but its size cannot constrained, nor its source. The convergence of ages and the multiplicity of sites would suggest at least one full size predecessor of the 2004 event 1000-800 years ago.

  2. Geological implications and controls on the determination of water saturation in shale gas reservoirs

    NASA Astrophysics Data System (ADS)

    Hartigan, David; Lovell, Mike; Davies, Sarah

    2014-05-01

    A significant challenge to the petrophysical evaluation of shale gas systems can be attributed to the conductivity behaviour of clay minerals and entrained clay bound waters. This is compounded by centimetre to sub-millimetre vertical and lateral heterogeneity in formation composition and structure. Where despite significant variation in formation geological and therefore petrophysical properties, we routinely rely on conventional resistivity methods for the determination of water saturation (Sw), and hence the free gas saturation (Sg) in gas bearing mudstones. The application of resistivity based methods is the subject of continuing debate, and there is often significant uncertainty in both how they are applied and the saturation estimates they produce. This is partly a consequence of the view that "the quantification of the behaviour of shale conductivity....has only limited geological significance" (Rider 1986). As a result, there is a separation between our geological understanding of shale gas systems and the petrophysical rational and methods employed to evaluate them. In response to this uncertainty, many petrophysicists are moving away from the use of more complex 'shaly-sand' based evaluation techniques and returning to traditional Archie methods for answers. The Archie equation requires various parameter inputs such as porosity and saturation exponents (m and n), as well as values for connate fluid resistivity (Rw). Many of these parameters are difficult to determine in shale gas systems, where obtaining a water sample, or carrying out laboratory experiments on recovered core is often technically impractical. Here we assess the geological implications and controls on variations in pseudo Archie parameters across two geological formations, using well data spanning multiple basinal settings for a prominent shale gas play in the northern Gulf of Mexico basin. The results, of numerical analysis and systematic modification of parameter values to minimise the

  3. Comparative study of activation analyses for the determination of trace halogens in geological and cosmochemical samples.

    PubMed

    Nakamoto, Tomoshi; Oura, Yasuji; Ebihara, Mitsuru

    2007-09-01

    Halogens (fluorine, chlorine, bromine and iodine) were determined by activation analyses (neutron activation analysis (NAA), photon activation analysis (PAA) and prompt gamma-ray analysis (PGA)) for geological and cosmochemical solid samples. We studied how each analytical method was for the determination of trace amounts of halogens in rock samples. Radiochemical NAA (RNAA) showed the highest analytical reliability for three halogens (chlorine, bromine and iodine), whereas a set of four halogens (fluorine, chlorine, bromine and iodine) could be determined in principle by radiochemical PAA (RPAA) from a single specimen. Although it is a non-destructive method, PGA showed an analytical sensitivity for chlorine comparable to those of RNAA and RPAA.

  4. Atomic absorption spectrometric determination of copper, zinc, and lead in geological materials

    USGS Publications Warehouse

    Sanzolone, R.F.; Chao, T.T.

    1976-01-01

    An atomic absorption spectrometric method is described for the determination of copper, zinc, and lead in geological materials. The sample is digested with HF-HCl-H2O2; the final solution for analysis is in 10 % (v/v) HCl. Copper and zinc are determined directly by aspirating the solution into an air-acetylene flame. A separate aliquot of the solution is used for determination of lead; lead is extracted into TOPO-MIBK from the acidic solution in the presence of iodide and ascorbic acid. For a 0.50-g sample, the limits of determination are 10-2000 p.p.m. for Cu and Zn, and 5-5000 p.p.m. for Pb. As much as 40 % Fe or Ca. and 10 % Al, Mg, or Mn in the sample do not interfere. The proposed method can be applied to the determination of copper, zinc, and lead in a wide range of geological materials including iron- and manganese-rich, calcareous and carbonate samples. ?? 1976.

  5. The K-PG boundary: how geological events lead to collapse of marine primary producers

    NASA Astrophysics Data System (ADS)

    Hir guillaume, Le; frederic, Fluteau; yves, Goddéris

    2017-04-01

    The cause(s) of Cretaceous/Paleogene (K-Pg) mass extinction event is a matter of debate since three decades. A first scenario connects the K-Pg crisis with the Chicxulub impact while the second scenario evokes the emplacement of the Deccan traps in India as the cause for the K-Pg biodiversity collapse. Pierazzo et al. (1998) estimated that the extraterrestrial bolide lead to an instantaneously CO2 degassing ranging from 880 Gt to 2,960 Gt into the atmosphere, together with a massive release of SO2 ranging from 150 to 460 Gt.. Self et al. (2006, 2008) and Chenet et al. (2009) suggested that the emplacement of the Deccan traps released 15,000 Gt to 35,000 Gt of CO2 and 6,800 Gt to 17,000 Gt of SO2 over a 250 kyr-long period (Schoene et al., 2015). To decipher and quantify the long term environmental consequences of both events, we tested different scenarios: a pulse-like magmatic degassing, a bolide impact, and a combination of both. To understand the environmental changes and quantify biodiversity responses, we improve GEOCLIM, a coupled climate-carbon numerical model, by implementing a biodiversity model in which marine species are described by specific death/born rates, sensitivity to abiotic factors (temperature, pH, dissolved O2, calcite saturation state) and feeding relationships, each of these characteristics is assigned randomly. Preliminary simulations accounting for the eruption of the Deccan traps show that successive cooling events (S-aerosols effect) combined with a progressive acidification of surface water (caused by CO2 and SO2 injections) cause a major collapse of the marine biomass. Additional simulations in which Chicxulub impact, different community structures of primary producers will be discussed.

  6. Estimating the duration of geologic intervals from a small number of age determinations: A challenge common to petrology and paleobiology

    NASA Astrophysics Data System (ADS)

    Glazner, Allen F.; Sadler, Peter M.

    2016-12-01

    The duration of a geologic interval, such as the time over which a given volume of magma accumulated to form a pluton, or the lifespan of a large igneous province, is commonly determined from a relatively small number of geochronologic determinations (e.g., 4-10) within that interval. Such sample sets can underestimate the true length of the interval by a significant amount. For example, the average interval determined from a sample of size n = 5, drawn from a uniform random distribution, will underestimate the true interval by 50%. Even for n = 10, the average sample only captures ˜80% of the interval. If the underlying distribution is known then a correction factor can be determined from theory or Monte Carlo analysis; for a uniform random distribution, this factor is n+1n-1. Systematic undersampling of interval lengths can have a large effect on calculated magma fluxes in plutonic systems. The problem is analogous to determining the duration of an extinct species from its fossil occurrences. Confidence interval statistics developed for species origination and extinction times are applicable to the onset and cessation of magmatic events.

  7. Iridium abundance measurements across bio-event horizons in the geological record

    NASA Technical Reports Server (NTRS)

    Orth, C. J.; Attrep, M., Jr.

    1988-01-01

    Geochemical studies have been performed on thousands of rock samples collected across bio-event horizons in the fossil record using INAA for about 40 common and trace elements and radiochemical isolation procedures for Os, Ir, Pt, and Au on selected samples. These studies were begun soon after the Alvarez team announced their discovery of the Cretaceous-Tertiary (K-T) Ir anomaly in marine rock sequences in Europe. With their encouragement the Authors searched for the anomaly in nearby continental (freshwater coal swamp) deposits. In collaboration with scientists from the U.S.G.S. in Denver, the anomaly was located and it was observed that a floral crisis occurred at the same stratigraphic position as the Ir spike. Further work in the Raton Basin has turned up numerous well-preserved K-T boundary sections. Although the Authors have continued to study the K-T boundary and provide geochemical measurements for other groups trying to precisely locate it, the primary effort was turned to examining the other bio-events in the Phanerozoic, especially to those that are older than the terminal Cretaceous. A list of horizons that were examined in collaboration with paleontologists and geologists is given. Results are also given and discussed.

  8. Geological and oceanographic perspectives on event bed formation during Hurricane Katrina

    NASA Astrophysics Data System (ADS)

    Keen, T. R.; Furukawa, Y.; Bentley, S. J.; Slingerland, R. L.; Teague, W. J.; Dykes, J. D.; Rowley, C. D.

    2006-12-01

    Storm deposits in ancient shelf sediments typically form thick sequences of interbedded sand and mud deposited during shoreline regression, whereas modern shelf sediments are generally thin veneers deposited during shoreline transgression. In this paper we present a preliminary comparison between ancient and modern storm beds deposited in these disparate contexts. Hurricane Katrina deposited a storm bed on the Louisiana shelf with a maximum observed thickness of 0.58 m, which thinned to approximately 0.1 m at 200 km west of landfall. This thickness is similar to event beds observed in both ancient and modern sediments. Using data for tropical cyclone landfalls in the Gulf of Mexico, we estimate the return time for a storm of this size to be 40-50 years in this region. This estimated frequency for deposition of storm beds is useful in evaluating ancient storm sequences that were deposited during similar climatic conditions.

  9. Determination of femtogram quantities of protactinium in geologic samples by thermal ionization mass spectrometry

    SciTech Connect

    Pickett, D.A.; Murrell, M.T.; Williams, R.W. )

    1994-04-01

    We describe a procedure for measurement of [sup 231]Pa in geologic samples by isotope dilution thermal ionization mass spectrometry, using [sup 233]Pa as a spike isotope, which provides marked improvements in precision and sample size relative to established decay counting techniques. This method allows determination of as little as a few tens of femtograms of [sup 231]Pa (approximately 10[sup 3] atoms) with a conservative estimated uncertainty of [+-]1% (95% confidence level). Applications of [sup 231]Pa-[sup 235]U systematics to uranium-series geochemistry and geochronology should be greatly enhanced by this approach. 31 refs., 4 figs., 1 tab.

  10. Geological events play a larger role than Pleistocene climatic fluctuations in driving the genetic structure of Quasipaa boulengeri (Anura: Dicroglossidae).

    PubMed

    Yan, Fang; Zhou, Weiwei; Zhao, Haitao; Yuan, Zhiyong; Wang, Yunyu; Jiang, Ke; Jin, Jieqiong; Murphy, Robert W; Che, Jing; Zhang, Yaping

    2013-02-01

    Paleoclimatic and paleogeological events have been identified as being the two main drivers of genetic structuring in extant organisms. We used a montane stream-dwelling frog, Quasipaa boulengeri, to explore the relative roles played by these drivers on species in southern China, a region needing thorough studies. We detected four major matrilines, and no broadly distributed haplotypes occurred. The complex orogenesis of south-western China drove matrilineal divergence in Q. boulengeri into highly structured geographical units. These matrilines subsequently persisted in situ with stable populations rather than undergoing expansions during glacial cycling. The unification of the upper and middle Yangtze River in the Three Gorges mountain region mediated downstream colonization of this frog. Analyses identified geological events as playing a larger role than climatic fluctuations in driving the population history of Q. boulengeri. Nuclear allele analyses indicated gene flow; this maintained genetic cohesion of the species. South-eastern Sichuan Basin was identified as the area of secondary contact for several matrilines, and this area deserves further study and special protection.

  11. Determination of gold in geologic materials by solvent extraction and atomic-absorption spectrometry

    USGS Publications Warehouse

    Huffman, Claude; Mensik, J.D.; Riley, L.B.

    1967-01-01

    The two methods presented for the determination of traces of gold in geologic materials are the cyanide atomic-absorption method and the fire-assay atomic-absorption method. In the cyanide method gold is leached with a sodium-cyanide solution. The monovalent gold is then oxidized to the trivalent state and concentrated by extracting into methyl isobutyl ketone prior to estimation by atomic absorption. In the fire-assay atomic-absorption method, the gold-silver bead obtained from fire assay is dissolved in nitric and hydrochloric acids. Gold is then concentrated by extracting into methyl isobutyl ketone prior to determination by atomic absorption. By either method concentrations as low as 50 parts per billion of gold can be determined in a 15-gram sample.

  12. An atomic-absorption method for the determination of gold in large samples of geologic materials

    USGS Publications Warehouse

    VanSickle, Gordon H.; Lakin, Hubert William

    1968-01-01

    A laboratory method for the determination of gold in large (100-gram) samples has been developed for use in the study of the gold content of placer deposits and of trace amounts of gold in other geologic materials. In this method the sample is digested with bromine and ethyl ether, the gold is extracted into methyl isobutyl ketone, and the determination is made by atomicabsorption spectrophotometry. The lower limit of detection is 0.005 part per million in the sample. The few data obtained so far by this method agree favorably with those obtained by assay and by other atomic-absorption methods. About 25 determinations can be made per man-day.

  13. A neutron activation analysis procedure for the determination of uranium, thorium and potassium in geologic samples

    USGS Publications Warehouse

    Aruscavage, P. J.; Millard, H.T.

    1972-01-01

    A neutron activation analysis procedure was developed for the determination of uranium, thorium and potassium in basic and ultrabasic rocks. The three elements are determined in the same 0.5-g sample following a 30-min irradiation in a thermal neutron flux of 2??1012 n??cm-2??sec-1. Following radiochemical separation, the nuclides239U (T=23.5 m),233Th (T=22.2 m) and42K (T=12.36 h) are measured by ??-counting. A computer program is used to resolve the decay curves which are complex owing to contamination and the growth of daughter activities. The method was used to determine uranium, throium and potassium in the U. S. Geological Survey standard rocks DTS-1, PCC-1 and BCR-1. For 0.5-g samples the limits of detection for uranium, throium and potassium are 0.7, 1.0 and 10 ppb, respectively. ?? 1972 Akade??miai Kiado??.

  14. Atomic-absorption determination of beryllium in geological materials by use of electrothermal atomization

    USGS Publications Warehouse

    Campbell, E.Y.; Simon, F.O.

    1978-01-01

    A method is described for the atomic-absorption determination of beryllium in geological materials, that utilizes electrothermal atomization after a separation by solvent extraction. Samples are decomposed with hydrofluoric acid and nitric acid in Teflon-lined pressure decomposition vessels. Beryllium is isolated by its extraction as beryllium acetylacetonate at pH 8 into xylene and back-extraction in 3M hydrochloric acid. The method has been successfully applied to the determination of beryllium in 14 U.S. Geological Survey standard rocks. Four subsamples from four bottles of each standard sample were analysed in random order. The mean beryllium contents (ppm) are: AGV-1, 1.98; PCC-1, 0.024; MAG-1, 2.84; BHVO-1, 0.90; DTS-1, 0.026; SCo-1, 1.74; SDC-1, 2.52; BCR-1, 1.44; GSP-1, 1.22; SGR-1, 0.86; QLO-1, 1.83; RGM-1, 2.21; STM-1, 8.75; G-2, 2.29. An analysis of variance shows that all the samples may be considered homogeneous at F0.95 except AGV-1 and DTS-1 which may be considered homogeneous at F0.99. ?? 1978.

  15. Phylogeographic patterns of the Aconitum nemorum species group (Ranunculaceae) shaped by geological and climatic events in the Tianshan Mountains and their surroundings

    Treesearch

    Xiao-Long Jiang; Ming-Li Zhang; Hong-Xiang Zhang; Stewart C. Sanderson

    2014-01-01

    To investigate the impacts of ancient geological and climatic events on the evolutionary history of the Aconitum nemorum species group, including A. nemorum s. str., A. karakolicum, and A. soongoricum; a total of 18 natural populations with 146 individuals were sampled, mainly from grassy slopes or the coniferous forest understory of the Tianshan Mountain Range and its...

  16. Determination of the rare-earth elements in geological materials by inductively coupled plasma mass spectrometry

    USGS Publications Warehouse

    Lichte, F.E.; Meier, A.L.; Crock, J.G.

    1987-01-01

    A method of analysis of geological materials for the determination of the rare-earth elements using the Inductively coupled plasma mass spectrometric technique (ICP-MS) has been developed. Instrumental parameters and factors affecting analytical results have been first studied and then optimized. Samples are analyzed directly following an acid digestion, without the need for separation or preconcentration with limits of detection of 2-11 ng/g, precision of ?? 2.5% relative standard deviation, and accuracy comparable to inductively coupled plasma emission spectrometry and instrumental neutron activation analysis. A commercially available ICP-MS instrument is used with modifications to the sample introduction system, torch, and sampler orifice to reduce the effects of high salt content of sample solutions prepared from geologic materials. Corrections for isobaric interferences from oxide ions and other diatomic and triatomic ions are made mathematically. Special internal standard procedures are used to compensate for drift in metahmetal oxide ratios and sensitivity. Reference standard values are used to verify the accuracy and utility of the method.

  17. Radon potential determination by a combination of geological mapping, geochemistry, groundwater investigations and airborne geophysics

    NASA Astrophysics Data System (ADS)

    Schubert, G.; Motschka, K.; Ahl, A.; Slapansky, P.; Finger, F.; Alletsgruber, I.; Gasser, V.; Supper, R.; Bieber, G.

    2009-04-01

    During the nineties comprehensive Radon investigations were carried out in Austria to determine the Radon exposure of the population (Ditto et al., 1999, Friedmann et al.,1997 and Friedmann et al., 2007). Friedmann (2007, p 16-17) came to the result that indoor measurements can be better used than geological methods to pinpoint areas with a high Radon hazard. Contrary to this conclusion, in the current presentation we intend to show that geological factors are the most important parameters for Radon potential evaluation and we demonstrate a new mapping method for determining the spatial distribution of the Radon potential by means of geological and airborne geophysical investigations. Within the last years, several test sites in the southern Bohemian Massive were investigated. Based on large scaled geological maps different types of Granites were analysed on Uranium content. Furthermore, in order to obtain the spatial distribution of Uranium, close-meshed airborne radiometric mapping was carried out. Additionally, ground water samples were analysed to derive representative Radon concentrations for the pore volume within the different Granite types. Final results concluded that there is a significant correlation between the Uranium content of the geological subsurface and the Radon concentration in the ground water (SCHUBERT et al., 2003, ALLETSGRUBER, 2007). As a consequence airborne radiometric mapping could be used as an effective tool to derive quick and detailed information on spatial distribution of the Radon potential. Furthermore this methodology could contribute to identify potential Radon hot spot areas as only airborne radiometric mapping could provide countrywide Uranium data coverage in high resolution. I. Alletsgruber(2007): Radongehalte in Grundwässern des Mühlviertels (Oberösterreich). Geologische und hydrogeologische Faktoren. - diploma thesis, Univ. Salzburg. PT M. Ditto, W. Fimml, V. Karg, M. Korner, J. Weisz (1999): Radon-222 im Grundwasser

  18. Determination of palladium, platinum and rhodium in geologic materials by fire assay and emission spectrography

    USGS Publications Warehouse

    Hapfty, J.; Riley, L.B.

    1968-01-01

    A method is described for the determination of palladium down to 4ppb (parts per billion, 109), platinum down to 10 ppb and rhodium down to 5 ppb in 15 g of sample. Fire-assay techniques are used to preconcentrate the platinum metals into a gold bead, then the bead is dissolved in aqua regia and diluted to volume with 1M hydrochloric acid. The solution is analysed by optical emission spectrography of the residue from 200 ??l of it evaporated on a pair of flat-top graphite electrodes. This method requires much less sample handling than most published methods for these elements. Data are presented for G-1, W-1, and six new standard rocks of the U.S. Geological Survey. The values for palladium in W-1 are in reasonable agreement with previously published data. ?? 1968.

  19. Emission spectrographic determination of volatile trace elements in geologic materials by a carrier distillation technique

    USGS Publications Warehouse

    Barton, H.N.

    1986-01-01

    Trace levels of chalcophile elements that form volatile sulfide minerals are determined in stream sediments and in the nonmagnetic fraction of a heavy-mineral concentrate of stream sediments by a carrier distillation emission spectrographic method. Photographically recorded spectra of samples are visually compared with those of synthetic standards for the two sample types. Rock and soil samples may also be analyzed by comparison with the stream-sediment standards. A gallium oxide spectrochemical carrier/buffer enhances the early emission of the volatile elements. Detection limits in parts per million attained are: Sb 5, As 20, Bi 0.1, Cd 1, Cu 1, Pb 2, Ag 0.1, Zn 2, and Sn 0.1. A comparison with other methods of analysis, total-burn emission and atomic absorption spectroscopy, shows good correlation for standard reference for materials and samples from a variety of geologic terranes. ?? 1986.

  20. Matrix effects on the determination of manganese in geological materials by atomic-absorption spectrophotometry under different flame conditions

    USGS Publications Warehouse

    Sanzolone, R.F.; Chao, T.T.

    1978-01-01

    Suppression caused by five of the seven matrix elements studied (Si, Al, Fe, Ca and Mg) was observed in the atomic-absorption determination of manganese in geological materials, when synthetic solutions and the recommended oxidizing air-acetylene flame were used. The magnitude of the suppression effects depends on (1) the kind and concentration of the interfering elements, (2) the type of acid medium, and (3) the concentration of manganese to be determined. All interferences noted are removed or alleviated by using a reducing nitrous oxide-acetylene flame. The atomic-absorption method using this flame can be applied to the determination of total and extractable manganese in a wide range of geological materials without interferences. Analyses of six U.S. Geological Survey rock standards for manganese gave results in agreement with the reported values. ?? 1978.

  1. Geological evidence of oxygenic photosynthesis and the biotic response to the 2400-2200 ma "great oxidation event".

    PubMed

    Schopf, J William

    2014-03-01

    Fossil evidence of photosynthesis, documented in the geological record by microbially laminated stromatolites, microscopic fossils, and carbon isotopic data consistent with the presence of Rubisco-mediated CO2-fixation, extends to ~3500 million years ago. Such evidence, however, does not resolve the time of origin of oxygenic photosynthesis from its anoxygenic photosynthetic evolutionary precursor. Though it is evident that cyanobacteria, the earliest-evolved O2-producing photoautotrophs, existed before ~2450 million years ago - the onset of the "Great Oxidation Event" (GOE) that forever altered Earth's environment - O2-producing photosynthesis seems certain to have originated hundreds of millions of years earlier. How did Earth's biota respond to the GOE? Four lines of evidence are here suggested to reflect this major environmental transition: (1) rRNA phylogeny-correlated metabolic and biosynthetic pathways document evolution from an anaerobic (pre-GOE) to a dominantly oxygen-requiring (post-GOE) biosphere; (2) consistent with the rRNA phylogeny of cyanobacteria, their fossil record evidences the immediately post-GOE presence of cyanobacterial nostocaceans characterized by specialized cells that protect their oxygen-labile nitrogenase enzyme system; (3) the earliest known fossil eukaryotes, obligately aerobic phytoplankton and putative algae, closely post-date the GOE; and (4) microbial sulfuretums are earliest known from rocks deposited during and immediately after the GOE, their apparent proliferation evidently spurred by an increase of environmental oxygen and a resulting upsurge of metabolically useable sulfate and nitrate. Though the biotic response to the GOE is a question new to paleobiology that is yet largely unexplored, additional evidence of its impact seems certain to be uncovered.

  2. The Siberian Traps and the end-Permian event: Geology, geochemistry and atmospheric modeling of gas release

    NASA Astrophysics Data System (ADS)

    Svensen, Henrik; Stordal, Frode; Roscher, Marco; Sokalska, Ewa; Planke, Sverre

    2013-04-01

    , under current conditions, about 25 times larger than from a similar mass of CO2, i.e. the Global Warming Potential (GWP) is ~25, the climate impact of a mixture containing 60% CH4 is strongly dominated by this compound. This effect increases with the amount of available H2S as it strongly influences the lifetime of CH4 in the atmosphere by reducing the oxidation potential. The method and geological model can be applied to other boundary events with LIPs, such as the Triassic-Jurassic boundary (~3.1°C), the Toarcian event (~2.9°C), and the Palaeocene-Eocene Thermal Maximum (~3.5°C).

  3. Neutron activation determination of iridium, gold, platinum, and silver in geologic samples

    USGS Publications Warehouse

    Millard, H.T.

    1987-01-01

    Low-level methods for the determination of iridium and other noble metals have become increasingly important in recent years due to interest in locating abundance anomalies associated with the Cretaceous and Tertiary (K-T) boundary. Typical iridium anomalies are in the range of 1 to 100 ??g/kg (ppb). Thus methods with detection limits near 0.1 ??g/kg should be adequate to detect K-T boundary anomalies. Radiochemical neutron activation analysis methods continue to be required although instrumental neutron activation analysis techniques employing elaborate gamma-counters are under development. In the procedure developed in this study samples irradiated in the epithermal neutron facility of the U. S. Geological Survey TRIGA Reactor (Denver, Colorado) are treated with a mini-fire assay technique. The iridium, gold, and silver are collected in a 1-gram metallic lead button. Primary contaminants at this stage are arsenic and antimony. These can be removed by heating the button with a mixture of sodium perioxide and sodium hydroxide. The resulting 0.2-gram lead bead is counted in a Compton suppression spectrometer. Carrier yields are determined by reirradiation of the lead beads. This procedure has been applied to the U.S.G.S. Standard Rock PCC-1 and samples from K-T boundary sites in the Western Interior of North America. ?? 1987 Akade??miai Kiado??.

  4. Geoid determination with density hypotheses from isostatic models and geological information

    NASA Astrophysics Data System (ADS)

    Kuhn, M.

    2003-05-01

    Geoid determination by Stokes's formula requires a complete knowledge of the topographical mass density distribution in order to perform gravity reductions to the geoid boundary. However, deeper masses are also of interest, in order to produce a smooth field of gravity anomalies which will improve results from interpolation procedures. Until now, in most cases a constant mass density has been considered, which is a very rough approximation of reality. The influence on the geoid height coming from different mass density hypotheses given by the isostatic models of Pratt/Hayford, Airy/Heiskanen and Vening Meinesz is studied. Apart from a constant mass density value, additional density information deduced from geological maps and thick sedimentary layers is considered. An overview of how mass density distributions act within Stokes's theory is given. The isostatic models are considered in spherical and planar approximation, as well as with constant and lateral variable mass density of the topographical and deeper masses. Numerical results in a test area in south-west Germany show that the differences in the geoid height due to different density hypotheses can reach a magnitude of more than 1 decimetre, which is not negligible in a precise geoid determination with centimetre accuracy.

  5. Determination of rare earth elements in geological materials by inductively coupled argon plasma/atomic emission spectrometry

    USGS Publications Warehouse

    Crock, J.G.; Lichte, F.E.

    1982-01-01

    Inductively coupled argon plasma/optical emission spectrometery (ICAP/OES) is useful as a simultaneous, multielement analytical technique for the determination of trace elements in geological materials. A method for the determination of trace-level rare earth elements (REE) in geological materials using an ICAP 63-channel emission spectrometer is described. Separation and preconcentration of the REE and yttrium from a sample digest are achieved by a nitric acid gradient cation exchange and hydrochloric acid anion exchange. Precision of 1-4% relative standard deviation and comparable accuracy are demonstrated by the triplicate analysis of three splits of BCR-1 and BHVO-1. Analyses of other geological materials including coals, soils, and rocks show comparable precision and accuracy.

  6. Quantitative modal determination of geological samples based on X-ray multielemental map acquisition.

    PubMed

    Cossio, Roberto; Borghi, Alessandro; Ruffini, Raffaella

    2002-04-01

    Multielemental X-ray maps collected by a remote scanning system of the electron beam are processed by a dedicated software program performing accurate modal determination of geological samples. The classification of different mineral phases is based on elemental concentrations. The software program Petromod loads the maps into a database and computes a matrix consisting of numerical values proportional to the elemental concentrations. After an initial calibration, the program can perform the chemical composition calculated on the basis of a fixed number of oxygens for a selected area. In this way, it is possible to identify all the mineral phases occurring in the sample. Up to three elements can be selected to calculate the modal percentage of the identified mineral. An automated routine scans the whole set of maps and assigns each pixel that satisfies the imposed requirements to the selected phase. Repeating this procedure for every mineral phase occurring in the mapped area, a modal distribution of the rock-forming minerals can be performed. The final output consists of a digitized image, which can be further analyzed by common image analysis software, and a table containing the calculated modal percentages. The method is here applied to a volcanic and a metamorphic rock sample.

  7. The possibility of standardless analysis in graphite furnace atomic absorption spectrometry: determination of gold in geological samples

    NASA Astrophysics Data System (ADS)

    Wei-min, Yang; Zhe-ming, Ni

    1996-01-01

    This paper investigates the possibility of standardless analysis for gold in geological samples using graphite furnace atomic absorption spectrometry. A simplex optimization method is employed to select the optimum experimental conditions for both the conventional and fast furnace programs. The atomization efficiency ( ɛA = 100 × m0(calc)/ m0(exp)) for gold appears to be temperature dependent and is found to be around at 100% at higher atomization temperature. The results show that the standardless determination of gold could be performed in geological samples with the use of palladium as the matrix modifier and the accuracy is better than 7%.

  8. 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.

  9. Determinants and Drivers of Infectious Disease Threat Events in Europe

    PubMed Central

    Lindgren, Elisabet; Balkanyi, Laszlo; Espinosa, Laura; Almqvist, My S.; Penttinen, Pasi; Rocklöv, Joacim

    2016-01-01

    Infectious disease threat events (IDTEs) are increasing in frequency worldwide. We analyzed underlying drivers of 116 IDTEs detected in Europe during 2008–2013 by epidemic intelligence at the European Centre of Disease Prevention and Control. Seventeen drivers were identified and categorized into 3 groups: globalization and environment, sociodemographic, and public health systems. A combination of >2 drivers was responsible for most IDTEs. The driver category globalization and environment contributed to 61% of individual IDTEs, and the top 5 individual drivers of all IDTEs were travel and tourism, food and water quality, natural environment, global trade, and climate. Hierarchical cluster analysis of all drivers identified travel and tourism as a distinctly separate driver. Monitoring and modeling such disease drivers can help anticipate future IDTEs and strengthen control measures. More important, intervening directly on these underlying drivers can diminish the likelihood of the occurrence of an IDTE and reduce the associated human and economic costs. PMID:26982104

  10. Determinants and Drivers of Infectious Disease Threat Events in Europe.

    PubMed

    Semenza, Jan C; Lindgren, Elisabet; Balkanyi, Laszlo; Espinosa, Laura; Almqvist, My S; Penttinen, Pasi; Rocklöv, Joacim

    2016-04-01

    Infectious disease threat events (IDTEs) are increasing in frequency worldwide. We analyzed underlying drivers of 116 IDTEs detected in Europe during 2008-2013 by epidemic intelligence at the European Centre of Disease Prevention and Control. Seventeen drivers were identified and categorized into 3 groups: globalization and environment, sociodemographic, and public health systems. A combination of >2 drivers was responsible for most IDTEs. The driver category globalization and environment contributed to 61% of individual IDTEs, and the top 5 individual drivers of all IDTEs were travel and tourism, food and water quality, natural environment, global trade, and climate. Hierarchical cluster analysis of all drivers identified travel and tourism as a distinctly separate driver. Monitoring and modeling such disease drivers can help anticipate future IDTEs and strengthen control measures. More important, intervening directly on these underlying drivers can diminish the likelihood of the occurrence of an IDTE and reduce the associated human and economic costs.

  11. Determining the magnitude, frequency and source of prehistoric events - Is there a Holy Grail?

    NASA Astrophysics Data System (ADS)

    Goff, James; Dominey-Howes, Dale; Chague-Goff, Catherine; Strotz, Luke; Anning, David; Bird, Deanne; Calgaro, Emma; Courtney, Claire

    2010-05-01

    Over the last five years there has been a growing body of literature on efforts to try and identify evidence for prehistoric precursors of the 2004 Indian Ocean Tsunami. Similar work is also being carried out in many parts of the World and evidence for palaeotsunamis is slowly emerging - this is commendable. In some cases extensive databases for individual events have been, and continue to be, assembled. The Storegga Slide off Norway is probably the most comprehensive dataset collated for a single event and provides an excellent example of how the source and magnitude of a prehistoric tsunami can be assessed. As an increasing amount of information is gathered a growing number of palaeotsunamis are being recognised as "hybrids" - events that are historic in one country and prehistoric in another. The 1700AD Cascadia event is probably the most well-known of these, although the 1575AD Chilean tsunami is another one of increasing importance. Hybrid tsunamis help us to better understand the nature and extent of palaeotsunamis in regions with short historical records - Pacific Island nations are an excellent example. Globally, we are recognising that the study of contemporary tsunamis is a multi-disciplinary field. Not surprisingly, the same applies to palaeotsunamis. The collation and interpretation of data for these prehistoric events however, is fraught with difficulties and currently nearly every palaeotsunami database that has been developed consists almost entirely of geological data. In an increasingly multidisciplinary field this is severely limiting. We provide three examples from the New Zealand palaeotsunami database - one includes a range of multidisciplinary data for a local event, another is a distantly sourced hybrid, and the final one looks at regional source identification using multiple contemporaneous deposits. This is quite a remarkable dataset, but it throws up some interesting issues. To be able to effectively identify regional and distant

  12. In Situ Spectrophotometric Determination of pH under Geologic CO2 Sequestration Conditions: Method Development and Application

    SciTech Connect

    Shao, Hongbo; Thompson, Christopher J.; Qafoku, Odeta; Cantrell, Kirk J.

    2013-02-25

    Injecting massive amounts of CO2 into deep geologic formations will cause a range of coupled thermal, hydrodynamic, mechanical, and chemical changes. A significant perturbation in water-saturated formations is the pH drop in the reservoir fluids due to CO2 dissolution. Knowing the pH under geological CO2 sequestration conditions is important for a better understanding of the short- and long-term risks associated with geological CO2 sequestration and will help in the design of sustainable sequestration projects. Most previous studies on CO2-rock-brine interactions have utilized thermodynamic modeling to estimate the pH. In this work, a spectrophotometric method was developed to determine the in-situ pH in CO2-H2O-NaCl systems in the presence and absence of reservoir rock by observing the spectra of a pH indicator, bromophenol blue, with a UV-visible spectrophotometer. Effects of temperature, pressure, and ionic strength on the pH measurement were evaluated. Measured pH values in CO2-H2O-NaCl systems were compared with several thermodynamic models. Results indicate that bromophenol blue can be used to accurately determine the pH of brine in contact with supercritical CO2 under geologic CO2 sequestration conditions.

  13. An analysis of dinosaurian biogeography: evidence for the existence of vicariance and dispersal patterns caused by geological events.

    PubMed Central

    Upchurch, Paul; Hunn, Craig A; Norman, David B

    2002-01-01

    As the supercontinent Pangaea fragmented during the Mesozoic era, dinosaur faunas were divided into isolated populations living on separate continents. It has been predicted, therefore, that dinosaur distributions should display a branching ('vicariance') pattern that corresponds with the sequence and timing of continental break-up. Several recent studies, however, minimize the importance of plate tectonics and instead suggest that dispersal and regional extinction were the main controls on dinosaur biogeography. Here, in order to test the vicariance hypothesis, we apply a cladistic biogeographical method to a large dataset on dinosaur relationships and distributions. We also introduce a methodological refinement termed 'time-slicing', which is shown to be a key step in the detection of ancient biogeographical patterns. These analyses reveal biogeographical patterns that closely correlate with palaeogeography. The results provide the first statistically robust evidence that, from Middle Jurassic to mid-Cretaceous times, tectonic events had a major role in determining where and when particular dinosaur groups flourished. The fact that evolutionary trees for extinct organisms preserve such distribution patterns opens up a new and fruitful direction for palaeobiogeographical research. PMID:11916478

  14. An analysis of dinosaurian biogeography: evidence for the existence of vicariance and dispersal patterns caused by geological events.

    PubMed

    Upchurch, Paul; Hunn, Craig A; Norman, David B

    2002-03-22

    As the supercontinent Pangaea fragmented during the Mesozoic era, dinosaur faunas were divided into isolated populations living on separate continents. It has been predicted, therefore, that dinosaur distributions should display a branching ('vicariance') pattern that corresponds with the sequence and timing of continental break-up. Several recent studies, however, minimize the importance of plate tectonics and instead suggest that dispersal and regional extinction were the main controls on dinosaur biogeography. Here, in order to test the vicariance hypothesis, we apply a cladistic biogeographical method to a large dataset on dinosaur relationships and distributions. We also introduce a methodological refinement termed 'time-slicing', which is shown to be a key step in the detection of ancient biogeographical patterns. These analyses reveal biogeographical patterns that closely correlate with palaeogeography. The results provide the first statistically robust evidence that, from Middle Jurassic to mid-Cretaceous times, tectonic events had a major role in determining where and when particular dinosaur groups flourished. The fact that evolutionary trees for extinct organisms preserve such distribution patterns opens up a new and fruitful direction for palaeobiogeographical research.

  15. Determination of the Strike and Dip of Planar Geological Structures: A Computer Solution.

    ERIC Educational Resources Information Center

    Pizarro, Antonio

    1988-01-01

    Explains the use of the 3-dimensional analytic geometry method to find values for a field geology problem. Gives a description of the mathematical theory for this method which can be applied to data obtained by drilling as well as open surfaces, and a computer program. (RT)

  16. Fast-track extreme event attribution: General methods and techniques to determine the dynamic contribution to an event.

    NASA Astrophysics Data System (ADS)

    Otto, F. E. L.; Haustein, K.; Uhe, P.; Massey, N.; Rimi, R.; Allen, M. R.; Cullen, H. M.

    2016-12-01

    Extreme weather event attribution has become an accepted part of the atmospheric sciences with numerous methods having been put forward over the last decade. We have recently established a new framework which allows for event attribution in quasi-real-time. Here we present the methodology with which we can assess the fraction of attributable risk (FAR) of a severe weather event due to an external driver (Haustein et al. 2016). The method builds on a large ensemble of atmosphere-only GCM simulations forced by seasonal forecast SSTs (actual conditions) that are contrasted with ensembles forced by counterfactual SSTs (natural conditions). Having an associated 30 year actual and natural climatology in place, we are able to put the current event into a climatological context and determine the dynamic contribution that lead to the event as opposed to the thermodynamic contribution which would have made such an event more likely regardless of the synoptic situation. As a second independent method (also applicable in near-real-time), we apply pattern correlation to separate thermodynamic and dynamic contributions. Finally, using reanalysis data, we test whether our attributed dynamic contribution is also detectable in the observations. Despite the high monthly variability, ENSO related teleconnection patterns can be detected fairly robustly as we will demonstrate with a recent example during El Nino. The more consistent the 3 methods are, the more robust our results will be. We note that the choice of time scale matters a lot when determining the dynamic contribution as well as estimating the FAR (Uhe et al. 2016). The weather@home ensemble prediction approach is accompanied by two more methods based on observational data and the CMIP5 ensemble. If the FAR across 3 methods is consistent, we have reason to trust our central attribution statement. Two recent examples will be shown in order to demonstrate the feasibility (van Oldenborgh et al. 2016a/2016b), complemented by

  17. Determination of arsenic, antimony, bismuth, cadmium, copper, lead, molybdenum, silver and zinc in geological materials by atomic-absorption spectrometry

    USGS Publications Warehouse

    Viets, J.G.; O'Leary, R. M.; Clark, Robert J.

    1984-01-01

    Arsenic, antimony, bismuth, cadmium, copper, lead, molybdenum, silver and zinc are very useful elements in geochemical exploration. In the proposed method, geological samples are fused with potassium pyrosulphate and the fusate is dissolved in a solution of hydrochloric acid, ascorbic acid and potassium iodide. When this solution is shaken with a 10% V/V Aliquat 336 - isobutyl methyl ketone organic phase, the nine elements of interest are selectively partitioned in the organic phase. All nine elements can then be determined in the organic phase using flame atomic-absorption spectrometry. The method is rapid and allows the determination of Ag and Cd at levels down to 0.1 p.p.m., Cu, Mo, and Zn down to 0.5 p.p.m., Pb, Bi and Sb down to 1 p.p.m. and As down to 5 p.p.m. in geological materials.

  18. Determination of Mercury in Aqueous and Geologic Materials by Continuous Flow-Cold Vapor-Atomic Fluorescence Spectrometry (CVAFS)

    USGS Publications Warehouse

    Hageman, Philip L.

    2007-01-01

    New methods for the determination of total mercury in geologic materials and dissolved mercury in aqueous samples have been developed that will replace the methods currently (2006) in use. The new methods eliminate the use of sodium dichromate (Na2Cr2O7 ?2H2O) as an oxidizer and preservative and significantly lower the detection limit for geologic and aqueous samples. The new methods also update instrumentation from the traditional use of cold vapor-atomic absorption spectrometry to cold vapor-atomic fluorescence spectrometry. At the same time, the new digestion procedures for geologic materials use the same size test tubes, and the same aluminum heating block and hot plate as required by the current methods. New procedures for collecting and processing of aqueous samples use the same procedures that are currently (2006) in use except that the samples are now preserved with concentrated hydrochloric acid/bromine monochloride instead of sodium dichromate/nitric acid. Both the 'old' and new methods have the same analyst productivity rates. These similarities should permit easy migration to the new methods. Analysis of geologic and aqueous reference standards using the new methods show that these procedures provide mercury recoveries that are as good as or better than the previously used methods.

  19. Early events in alphavirus replication determine the outcome of infection.

    PubMed

    Frolov, Ilya; Akhrymuk, Maryna; Akhrymuk, Ivan; Atasheva, Svetlana; Frolova, Elena I

    2012-05-01

    Alphaviruses are a group of important human and animal pathogens. They efficiently replicate to high titers in vivo and in many commonly used cell lines of vertebrate origin. They have also evolved effective means of interfering with development of the innate immune response. Nevertheless, most of the alphaviruses are known to induce a type I interferon (IFN) response in vivo. The results of this study demonstrate that the first hours postinfection play a critical role in infection spread and development of the antiviral response. During this window, a balance is struck between virus replication and spread in vertebrate cells and IFN response development. The most important findings are as follows: (i) within the first 2 to 4 h postinfection, alphavirus-infected cells become unable to respond to IFN-β, and this occurs before the virus-induced decrease in STAT1 phosphorylation in response to IFN treatment. (ii) Most importantly, very low, subprotective doses of IFN-β, which do not induce the antiviral response in uninfected cells, have a very strong stimulatory effect on the cells' ability to express type I IFN and activate interferon-stimulated genes during subsequent infection with Sindbis virus (SINV). (iii) Small changes in SINV nsP2 protein affect its ability to inhibit cellular transcription and IFN release. Thus, the balance between type I IFN induction and the ability of the virus to develop further rounds of infection is determined in the first few hours of virus replication, when only low numbers of cells and infectious virus are involved.

  20. Detailed 40Ar/39Ar dating of geologic events associated with the Mantos Blancos copper deposit, northern Chile

    NASA Astrophysics Data System (ADS)

    Oliveros, Verónica; Féraud, Gilbert; Aguirre, Luis; Ramírez, Luis; Fornari, Michel; Palacios, Carlos; Parada, Miguel

    2008-03-01

    The 40Ar/39Ar geochronological method was applied to date magmatic and hydrothermal alteration events in the Mantos Blancos mining district in the Coastal Cordillera of northern Chile, allowing the distinction of two separate mineralization events. The Late Jurassic Mantos Blancos orebody, hosted in Jurassic volcanic rocks, is a magmatic-hydrothermal breccia-style Cu deposit. Two superimposed mineralization events have been recently proposed. The first event is accompanied by a phyllic hydrothermal alteration affecting a rhyolitic dome. The second mineralization event is related to the intrusion of bimodal stocks and sills inside the deposit. Because of the superposition of several magmatic and hydrothermal events, the obtained 40Ar/39Ar age data are complex; however, with a careful interpretation of the age spectra, it is possible to detect complex histories of successive emplacement, alteration, mineralization, and thermal resetting. The extrusion of Jurassic basic to intermediate volcanic rocks of the La Negra Formation is dated at 156.3 ± 1.4 Ma (2 σ) using plagioclase from an andesitic lava flow. The first mineralization event and associated phyllic alteration affecting the rhyolitic dome occurred around 155-156 Ma. A younger bimodal intrusive event, supposed to be equivalent to the bimodal stock and sill system inside the deposit, is probably responsible for the second mineralization event dated at ca. 142 Ma. Other low-temperature alteration events have been dated on sericitized plagioclase at ca. 145-146, 125, and 101 Ma. This is the first time that two distinct mineralization events have been documented from radiometric data for a copper deposit in the metallogenic belt of the Coastal Cordillera of northern Chile.

  1. Do people's goals for mass participation sporting events matter? A self-determination theory perspective.

    PubMed

    Coleman, S J; Sebire, S J

    2016-09-27

    Non-elite mass participation sports events (MPSEs) may hold potential as a physical activity promotion tool. Research into why people participate in these events and what goals they are pursuing is lacking. Grounded in self-determination theory, this study examined the associations between MPSE participants' goals, event experiences and physical activity. A prospective cohort study was conducted; pre-event, participants reported their goals for the event. Four weeks post-event, participants reported their motivation for exercise, perceptions of their event achievement and moderate-to-vigorous intensity physical activity (MVPA). Bivariate correlations and path analysis were performed on data from 114 adults. Intrinsic goals (e.g. health, skill and social affiliation) for the event were positively associated with perceptions of event achievement, whereas extrinsic goals (e.g. appearance or social recognition) were not. Event achievement was positively associated with post-event autonomous motivation, which in turn was positively associated with MVPA. Pursuing intrinsic but not extrinsic goals for MPSEs is associated with greater perceptions of event achievement, which in turn is associated with post-event autonomous motivation and MVPA. © The Author 2016. Published by Oxford University Press on behalf of Faculty of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  2. From flood-event to climate in an alpine context (Arve valley, France): methodological issues toward the confrontation of historical documentation and geological records

    NASA Astrophysics Data System (ADS)

    Mélo, Alain; Ployon, Estelle; Wilhelm, Bruno; Arnaud, Fabien

    2014-05-01

    various flood types. We were hence able to distinguish different types of flood events from localised thunderstorms, generalised thunderstorm activity in uppermost catchment areas toward generalised heavy precipitation affecting the whole river Arve Catchment area (~ 2500 km²).We hence point the diversity of meteorological situations susceptible to lead to the recording of flood events. In order to properly confront historical documents- and geological archives-based flood chronicles this diversity must thus be taken into account. In that aim, using time geography-based representations may help in attributing a given record to a given meteorological context.

  3. The kinematics of northern South Island, New Zealand, determined from geologic strain rates

    NASA Astrophysics Data System (ADS)

    Holt, William E.; Haines, A. J.

    1995-09-01

    Relative motions within the distributed plate boundary zone of northern South Island, New Zealand, are determined through an inversion of geologic strain rate estimates. The Quaternary fault slip rate estimates define the shear strain rates, and rock uplift rates provide information on the horizontal divergence rates. An erosion rate to rock uplift rate ratio along with a crustal compensation factor is estimated in order to convert rock uplift rates to horizontal divergence rates. Because of the uncertainty in erosion rates, horizontal divergence rates σ˙ are given a large standard error of ± σ˙. The three horizontal strain rate components obtained from these data completely define the horizontal velocity gradient tensor. Strain rate distributions are matched with spline polynomial functions, which can be constrained to behave rigidly within specified regions, such as the Pacific or Australian plates. Inversion of the strain rate distribution, assuming uniform erosion rates across the northern South Island, yields a velocity field that has small differences in both magnitude (10% larger) and direction with the NUVEL-1A plate motion model between Pacific and Australian plates. A revised strain rate data set, obtained from a variable erosion model in which erosion rates are a linear function of the log of the average annual rainfall magnitudes, yields a velocity field with expected directions that are indistinguishable from the NUVEL-1A plate motion model between Pacific and Australian plates, but velocity magnitudes are still 10-15% higher than the plate motion model. Therefore the average values of slip rate on strike-slip faults in Marlborough, required by the NUVEL-1A plate motion model, are typically close to the low end of the published range of slip values for those structures. The major strike-slip structures within the Marlborough region are accommodating 80-100% of the total plate motion between Australia and Pacific plates on northern South Island; as

  4. Hypocenter Determination Using a Non-Linear Method for Events in West Java, Indonesia: A Preliminary Result

    NASA Astrophysics Data System (ADS)

    Rosalia, Shindy; Widiyantoro, Sri; Nugraha, Andri Dian; Ash Shiddiqi, Hasbi; Supendi, Pepen; Wandono

    2017-04-01

    West Java, part of the Sunda Arc, has relatively high seismicity due to subduction activity and faulting. The first step of tomography study in order to infer the geometry of the structure beneath West Java is to conduct precise earthquake hypocenter determination. In this study, we used earthquake waveform data taken from the regional Meteorological, Climatological, Geophysical Agency (BMKG) network from South Sumatra to central Java. We have repicked P and S arrival times from about 800 events in the period from April 2009 to December 2015. We selected the events which have azimuthal gap < 210° and phase more than 8. The non-linear method employed in this study used the oct-tree sampling algorithm from NonLinLoc program to determine the earthquake hypocenters. The hypocenter location results give better clustering earthquakes which are correlated well with geological structure in the study region. We also compared our results with BMKG catalog data and found that the average hypocenter location difference is about 12 km in latitude direction, 9.5 km in longitude direction, and the average focal depth difference is about 19.5 km. For future studies, we will conduct tomographic imaging to invert 3-D seismic velocity structure beneath the western part of Java.

  5. Quaternary Geologic History of the Rio Tambo, Southern Peru: Repeated Mass-Wasting Events in Western Cordillera Drainages

    NASA Astrophysics Data System (ADS)

    Davis, M. W.; Hall, S. R.; Farber, D. L.; Audin, L.; Finkel, R.

    2007-12-01

    The amount and timing of river incision along the western margin of the Altiplano can provide insight into the climatic, volcanic, and tectonic history of this region. While many studies have focused on the Tertiary geologic history of the western margin of the Altiplano, the Quaternary geologic history of this margin remains largely unstudied. The Pacific draining Rio Tambo river valley in the forearc of southern Peru is one of the large drainages of the western margin. While much of this river is presently cutting bedrock, many locations within the main and tributary channels contain lacustrian, landslide, and volcanic ash deposits of Quaternary age (?). While geomorphologic features such as active and abandoned alluvial fans, fluvial terraces (strath and fill), and pediment surfaces exist along multiple segments of this drainage current geologic maps of the area lack the spatial resolution to effectively use these deposits for constructing the geomorphic evolution of the area. Thus, we have mapped the Quaternary (?) features through field measurements using a theodolite, as well as from remotely sensed data including SRTM DEMs, stereo-pair aerial photos, and ASTER images. Using cosmogenic 10Be to date the surfaces, we are able to place bounds on the age of terrace, lacustrian, and landslide deposits. Although fluvial incision is an important erosive process, which has resulted in this high-relief landscape, we find extensive evidence that mass-wasting is here extremely effective at facilitating the rapid movement of large amounts of material. At numerous times throughout the Quaternary, huge debris flows have dammed the steep fluvial valleys producing vast lakes and thick (up to ~100m ) lacustrian deposits upstream of the landslide deposits. At present, the landslide and lacustrian deposits have been re-incised, in many cases, to bedrock, and only stranded lake and landslide deposits remain high on valley walls. Thus, a large amount of material has been

  6. Geological units and Moho depth determination in the Western Balkans exploiting GOCE data

    NASA Astrophysics Data System (ADS)

    Sampietro, D.

    2015-08-01

    In the present work we illustrate a new local inversion algorithm to retrieve the Moho depth from GOCE (Gravity field and steady-state Ocean Circulation Explorer) gravity field. In details the proposed procedure can be divided into two main steps: the first one consists in recognizing and isolating the different geological provinces in the study area by exploiting information coming from the GOCE global gravity field model. Once the main geological provinces are defined, a function relating the crust density of each province with depth is built and used to reduce the data. The gravitational effects of sediments, topography, bathymetry and upper mantle are also removed. In the second step the residual gravitational field is inverted to retrieve the Moho depth and some information on the crustal density. In particular, the clustering of geological province is performed by means of an automatic Bayesian classification algorithm while the inversion of GOCE residual field is performed by adapting the global algorithm developed in the framework of the GEMMA project to the local scale. The procedure, based on an iterative Wiener filter, allows to compute the Moho depth considering lateral as well as radial variations of crustal density. The algorithm has been applied to the fifth release of GOCE time-wise global gravity field model to infer information on the crustal structure in the Western Balkan area, that is, the region laying between Bulgaria and the Adriatic Sea. This region is one of the most complex and active, from the tectonic point of view, in the whole Europe and it is characterized by the presence of the Alpine-Himalayan orogenic belt, formed by the collision between the African and Eurasian plates, and by the opening of the Pannonian Basin. Results show a good agreement between the obtained geological provinces with the actual knowledge on the region. The resulting Moho depth ranges between about 20 km beneath the Adriatic Sea and 45 km in the Dinarides

  7. Method and apparatus for detecting and determining event characteristics with reduced data collection

    NASA Technical Reports Server (NTRS)

    Totman, Peter D. (Inventor); Everton, Randy L. (Inventor); Egget, Mark R. (Inventor); Macon, David J. (Inventor)

    2007-01-01

    A method and apparatus for detecting and determining event characteristics such as, for example, the material failure of a component, in a manner which significantly reduces the amount of data collected. A sensor array, including a plurality of individual sensor elements, is coupled to a programmable logic device (PLD) configured to operate in a passive state and an active state. A triggering event is established such that the PLD records information only upon detection of the occurrence of the triggering event which causes a change in state within one or more of the plurality of sensor elements. Upon the occurrence of the triggering event, the change in state of the one or more sensor elements causes the PLD to record in memory which sensor element detected the event and at what time the event was detected. The PLD may be coupled with a computer for subsequent downloading and analysis of the acquired data.

  8. Determination of total tin in geological materials by electrothermal atomic-absorption spectrophotometry using a tungsten-impregnated graphite furnace

    USGS Publications Warehouse

    Zhou, L.; Chao, T.T.; Meier, A.L.

    1984-01-01

    An electrothermal atomic-absorption spectrophotometric method is described for the determination of total tin in geological materials, with use of a tungsten-impregnated graphite furnace. The sample is decomposed by fusion with lithium metaborate and the melt is dissolved in 10% hydrochloric acid. Tin is then extracted into trioctylphosphine oxide-methyl isobutyl ketone prior to atomization. Impregnation of the furnace with a sodium tungstate solution increases the sensitivity of the determination and improves the precision of the results. The limits of determination are 0.5-20 ppm of tin in the sample. Higher tin values can be determined by dilution of the extract. Replicate analyses of eighteen geological reference samples with diverse matrices gave relative standard deviations ranging from 2.0 to 10.8% with an average of 4.6%. Average tin values for reference samples were in general agreement with, but more precise than, those reported by others. Apparent recoveries of tin added to various samples ranged from 95 to 111% with an average of 102%. ?? 1984.

  9. Linear geologic structure and magic rock discrimination as determined from infrared data

    NASA Technical Reports Server (NTRS)

    Offield, T. W.; Rowan, L. C.; Watson, R. D.

    1970-01-01

    Color infrared photographs of the Beartooth Mountains, Montana show the distribution of mafic dikes and amphibolite bodies. Lineaments that cross grassy plateaus can be identified as dikes by the marked constrast between the dark rocks and the red vegetation. Some amphibolite bodies in granitic terrain can also be detected by infrared photography and their contacts can be accurately drawn due to enchanced contrast of the two types of rock in the near infrared. Reflectance measurements made in the field for amphibolite and granite show that the granite is 25% to 50% more reflective in the near infrared than in the visible region. Further enhancement is due to less atmospheric scattering than in the visible region. Thermal infrared images of the Mill Creek, Oklahoma test site provided information on geologic faults and fracture systems not obtainable from photographs. Subtle stripes that cross outcrop and intervening soil areas and which probably record water distribution are also shown on infrared photographs.

  10. Linear geologic structure and magic rock discrimination as determined from infrared data

    NASA Technical Reports Server (NTRS)

    Offield, T. W.; Rowan, L. C.; Watson, R. D.

    1970-01-01

    Color infrared photographs of the Beartooth Mountains, Montana show the distribution of mafic dikes and amphibolite bodies. Lineaments that cross grassy plateaus can be identified as dikes by the marked constrast between the dark rocks and the red vegetation. Some amphibolite bodies in granitic terrain can also be detected by infrared photography and their contacts can be accurately drawn due to enchanced contrast of the two types of rock in the near infrared. Reflectance measurements made in the field for amphibolite and granite show that the granite is 25% to 50% more reflective in the near infrared than in the visible region. Further enhancement is due to less atmospheric scattering than in the visible region. Thermal infrared images of the Mill Creek, Oklahoma test site provided information on geologic faults and fracture systems not obtainable from photographs. Subtle stripes that cross outcrop and intervening soil areas and which probably record water distribution are also shown on infrared photographs.

  11. Relating Nearshore Algal Blooms Determined Using Satellite Imagery to Nutrient Loading, Watershed Land Use, and Storm Events

    NASA Astrophysics Data System (ADS)

    Stevenson, R. J.; Hyndman, D. W.; Qi, J.; Esselman, P.; Novitski, L.; Kendall, A. D.; Martin, S. L.; Lin, S.

    2014-12-01

    The overarching goal of our project was to relate algal biomass in the coastal zone of the Great Lakes, nutrient concentrations, watershed land use, and storm events. Algal biomass was determined using MODIS and Landsat remote sensing images. Nutrient loading from rivers into coastal zones was estimated with watershed land use, soils, geology, size and precipitation records. Our models of chlorophyll a based on remote sensing images (RS inferred chl a) and nutrient loading in coastal zones were validated with measured chlorophyll concentrations in the Great Lakes and nutrients in rivers. RS-inferred chl a was related to nutrient loading from rivers, which was dependent upon recent storm events and land use in watersheds. RS-inferred chl a was more related to nutrient loads during the week preceeding measurement of chl a than other periods before or during chl measurement. This lag time is presumably related to algal growth following nutrient loading, and was non-linearly related to nutrient loading. Our results indicate that these tools will improve understanding of land use effects on algal blooms in coastal zones of the Great Lakes and will help identify priority watersheds for restoration.

  12. Global Geologic Map of Europa

    NASA Technical Reports Server (NTRS)

    Doggett, T.; Figueredo, P.; Greeley, R.; Hare, T.; Kolb, E.; Mullins, K.; Senske, D.; Tanaka, K.; Weiser, S.

    2008-01-01

    Europa, with its indications of a sub-ice ocean, is of keen interest to astrobiology and planetary geology. Knowledge of the global distribution and timing of Europan geologic units is a key step for the synthesis of data from the Galileo mission, and for the planning of future missions to the satellite. The first geologic map of Europa was produced at a hemisphere scale with low resolution Voyager data. Following the acquisition of higher resolution data by the Galileo mission, researchers have identified surface units and determined sequences of events in relatively small areas of Europa through geologic mapping using images at various resolutions acquired by Galileo's Solid State Imaging camera. These works provided a local to subregional perspective and employed different criteria for the determination and naming of units. Unified guidelines for the identification, mapping and naming of Europan geologic units were put forth by and employed in regional-to-hemispheric scale mapping which is now being expanded into a global geologic map. A global photomosaic of Galileo and Voyager data was used as a basemap for mapping in ArcGIS, following suggested methodology of all-stratigraphy for planetary mapping. The following units have been defined in global mapping and are listed in stratigraphic order from oldest to youngest: ridged plains material, Argadnel Regio unit, dark plains material, lineaments, disrupted plains material, lenticulated plains material and Chaos material.

  13. Mid Holocene Evidence of High Energy Events in the Geological Record: Sedimentary Deposits from Cauvery Delta Coast, SE Coast of India.

    NASA Astrophysics Data System (ADS)

    Karthikeyan, A.; Seshachalam, S.; Jonathan, M. P.; Roy, P. D.

    2014-12-01

    The Cauvery Basin is one of the important sedimentary basins of southern India and provides information on geological processes since the Cretaceous. Most of the studies in the basin have been carried out on the sediments representing Cretaceous with less emphasis on the Quaternary period with marine high energy event. In the present study, we present the sedimentological and micro fauna assemblages in the 150 cm long trench from the Kameshwaram village, Nagapattinam District, South East Coast of India, in order to reconstruct the past event. OSL and Carbon dating of sand layer sediments from the Cauvery Basin provide the first proxy-record of marine event from the region over the Mid Holocene. A multi proxy approach using trench sediments from Cauvery Delta Coast, East coast of Tamil Nadu provides a high resolution record of high energy event. The dating of the event layer indicates 6 and 8 kyrs also below the layer shell layer was preserved, the radio carbon date of the shell layer was 6545 BC. A combination of sedimentological parameters of grain size, sorting, geochemical analysis (XRF) of Fe, Mn, Ti, Cr, Cu, Ni, Sr, Zr and foraminifera species like Ammonia beccarri, Ammonia dentate and Asterorotalia trispinosa were identified. The sediment layers have thinning-up sequences and it starts from 130 cm to the bottom of the layer 150 cm which included shell debris, and rip-up clasts. In addition, characteristic variations in elemental content at the bottom units of Zr, Ti, Ca is showing higher concentration, which is an indicator of high-energy depositional event often associated with an increase in Ti (2.08 % to 16.016 %) and Sr (116 ppm to 275 ppm). Ca on the other hand suggests a marine influence and Fe, Mn, Cr, Ni values are showing lower concentration indicating that the high marine energy event had inundated the Nagapattinam district in SE coast of India. Based on the multiproxy evidences, we conclude that this could be a major marine event during the Mid

  14. Sample Size Determination in Shared Frailty Models for Multivariate Time-to-Event Data

    PubMed Central

    Chen, Liddy M.; Ibrahim, Joseph G.; Chu, Haitao

    2014-01-01

    The frailty model is increasingly popular for analyzing multivariate time-to-event data. The most common model is the shared frailty model. Although study design consideration is as important as analysis strategies, sample size determination methodology in studies with multivariate time-to-event data is greatly lacking in the literature. In this paper, we develop a sample size determination method for the shared frailty model to investigate the treatment effect on multivariate event times. We analyzed the data using both a parametric model and a piecewise model with unknown baseline hazard, and compare the empirical power with the calculated power. Last, we discuss the formula for testing the treatment effect on recurrent events. PMID:24697252

  15. Sample size determination in shared frailty models for multivariate time-to-event data.

    PubMed

    Chen, Liddy M; Ibrahim, Joseph G; Chu, Haitao

    2014-01-01

    The frailty model is increasingly popular for analyzing multivariate time-to-event data. The most common model is the shared frailty model. Although study design consideration is as important as analysis strategies, sample size determination methodology in studies with multivariate time-to-event data is greatly lacking in the literature. In this article, we develop a sample size determination method for the shared frailty model to investigate the treatment effect on multivariate event times. We analyzed the data using both a parametric model and a piecewise model with unknown baseline hazard, and compare the empirical power with the calculated power. Last, we discuss the formula for testing the treatment effect on recurrent events.

  16. Using a Geographic Information System to determine the relation between stream quality and geology in the Roberts Creek watershed, Clayton County, Iowa

    USGS Publications Warehouse

    Kalkhoff, Stephen J.

    1993-01-01

    A geographic information system (GIS) was used to determine the relation between the stream-water quality and underlying geology in Roberts Creek watershed, Clayton County, Iowa, for base-flow conditions during the spring and summer of 1988–90. Geologic, stream, basin and subbasin boundaries, and water-quality sampling-site coverages were created by digitizing available maps. A contour coverage was created from digital line-graph data. The areal extent of geologic units subcropping in each subbasin was quantified with GIS, and the results then were output and joined with the discharge and water-quality data for statistical analyses. Illustrations showing the geology of the study area and the results of the study were prepared using GIS. By using GIS and a statistical software package, a weak but statistically significant relation was found between the water temperature, pH, and nitrogen concentrations in Roberts Creek and the underlying geology during base-flow conditions.

  17. A Deep Space Orbit Determination Software: Overview and Event Prediction Capability

    NASA Astrophysics Data System (ADS)

    Kim, Youngkwang; Park, Sang-Young; Lee, Eunji; Kim, Minsik

    2017-06-01

    This paper presents an overview of deep space orbit determination software (DSODS), as well as validation and verification results on its event prediction capabilities. DSODS was developed in the MATLAB object-oriented programming environment to support the Korea Pathfinder Lunar Orbiter (KPLO) mission. DSODS has three major capabilities: celestial event prediction for spacecraft, orbit determination with deep space network (DSN) tracking data, and DSN tracking data simulation. To achieve its functionality requirements, DSODS consists of four modules: orbit propagation (OP), event prediction (EP), data simulation (DS), and orbit determination (OD) modules. This paper explains the highest-level data flows between modules in event prediction, orbit determination, and tracking data simulation processes. Furthermore, to address the event prediction capability of DSODS, this paper introduces OP and EP modules. The role of the OP module is to handle time and coordinate system conversions, to propagate spacecraft trajectories, and to handle the ephemerides of spacecraft and celestial bodies. Currently, the OP module utilizes the General Mission Analysis Tool (GMAT) as a third-party software component for highfidelity deep space propagation, as well as time and coordinate system conversions. The role of the EP module is to predict celestial events, including eclipses, and ground station visibilities, and this paper presents the functionality requirements of the EP module. The validation and verification results show that, for most cases, event prediction errors were less than 10 millisec when compared with flight proven mission analysis tools such as GMAT and Systems Tool Kit (STK). Thus, we conclude that DSODS is capable of predicting events for the KPLO in real mission applications.

  18. Deformation rates across the San Andreas Fault system, central California determined by geology and geodesy

    NASA Astrophysics Data System (ADS)

    Titus, Sarah J.

    The San Andreas fault system is a transpressional plate boundary characterized by sub-parallel dextral strike-slip faults separating internally deformed crustal blocks in central California. Both geodetic and geologic tools were used to understand the short- and long-term partitioning of deformation in both the crust and the lithospheric mantle across the plate boundary system. GPS data indicate that the short-term discrete deformation rate is ˜28 mm/yr for the central creeping segment of the San Andreas fault and increases to 33 mm/yr at +/-35 km from the fault. This gradient in deformation rates is interpreted to reflect elastic locking of the creeping segment at depth, distributed off-fault deformation, or some combination of these two mechanisms. These short-term fault-parallel deformation rates are slower than the expected geologic slip rate and the relative plate motion rate. Structural analysis of folds and transpressional kinematic modeling were used to quantify long-term distributed deformation adjacent to the Rinconada fault. Folding accommodates approximately 5 km of wrench deformation, which translates to a deformation rate of ˜1 mm/yr since the start of the Pliocene. Integration with discrete offset on the Rinconada fault indicates that this portion of the San Andreas fault system is approximately 80% strike-slip partitioned. This kinematic fold model can be applied to the entire San Andreas fault system and may explain some of the across-fault gradient in deformation rates recorded by the geodetic data. Petrologic examination of mantle xenoliths from the Coyote Lake basalt near the Calaveras fault was used to link crustal plate boundary deformation at the surface with models for the accommodation of deformation in the lithospheric mantle. Seismic anisotropy calculations based on xenolith petrofabrics suggest that an anisotropic mantle layer thickness of 35-85 km is required to explain the observed shear wave splitting delay times in central

  19. Atomic-absorption spectrometric determination of cobalt, nickel, and copper in geological materials with matrix masking and chelation-extraction

    USGS Publications Warehouse

    Sanzolone, R.F.; Chao, T.T.; Crenshaw, G.L.

    1979-01-01

    An atomic-absorption spectrometric method is reported for the determination of cobalt, nickel, and copper in a variety of geological materials including iron- and manganese-rich, and calcareous samples. The sample is decomposed with HP-HNO3 and the residue is dissolved in hydrochloric acid. Ammonium fluoride is added to mask iron and 'aluminum. After adjustment to pH 6, cobalt, nickel, and copper are chelated with sodium diethyl-dithiocarbamate and extracted into methyl isobutyl ketone. The sample is set aside for 24 h before analysis to remove interferences from manganese. For a 0.200-g sample, the limits of determination are 5-1000 ppm for Co, Ni, and Cu. As much as 50% Fe, 25% Mn or Ca, 20% Al and 10% Na, K, or Mg in the sample either individually or in various combinations do not interfere. Results obtained on five U.S. Geological Survey rock standards are in general agreement with values reported in the literature. ?? 1979.

  20. Determination of microseismic event azimuth from S-wave splitting analysis

    NASA Astrophysics Data System (ADS)

    Yuan, Duo; Li, Aibing

    2017-02-01

    P-wave hodogram analysis has been the only reliable method to obtain microseismic event azimuths for one-well monitoring. However, microseismic data usually have weak or even no P-waves due to near double-couple focal mechanisms and limited ray path coverage, which causes large uncertainties in determined azimuths and event locations. To solve this problem, we take advantage of S-waves, which are often much stronger than P waves in microseismic data, and determine event azimuths by analyzing S-wave splitting data. This approach utilizes the positive correlation between the accuracy of event azimuth and the effectiveness of measuring S-wave splitting parameters and finds the optimal azimuth through a grid search. We have demonstrated that event azimuths can be well constrained from S-wave splitting analysis using both synthetic and field microseismic data. This method is less sensitive to noise than the routine P-wave hodogram method and provides a new way of determining microseismic event azimuths.

  1. Cold dissolution method for the determination of uranium in various geological materials at trace levels by laser fluorimetry.

    PubMed

    Ramdoss, K; Amma, B G; Umashankar, V; Rangaswamy, R

    1997-06-01

    A cold dissolution procedure for the determination of uranium in various geological materials like rocks, minerals, soils etc., has been described. Samples are allowed to react with HF and HNO(3) at room temperature overnight. Boric acid is added to complex excess fluoride ions. From the clear solution thus obtained, uranium is determined directly in laser fluorimeter after the addition of fluorescence enhancing reagents. The results of few standard reference materials analysed by the present method agree with the certified values. This methodology does not require platinum or teflon ware, exhaust system and time consuming solvent extraction step. Hazardous acid vapours are not left in air, so there is no air pollution. Chemicals consumption is minimal. Therefore the method is economical. The method can be employed for high sample throughput which is the prerequisite for exploration geochemists.

  2. Combined palaeomagnetic secular variation and petrophysical records to time-constrain geological and hazardous events: An example from the eastern Tyrrhenian Sea over the last 120 ka

    NASA Astrophysics Data System (ADS)

    Iorio, Marina; Liddicoat, Joseph; Budillon, Francesca; Incoronato, Alberto; Coe, Robert S.; Insinga, Donatella D.; Cassata, William S.; Lubritto, Carmine; Angelino, Antimo; Tamburrino, Stella

    2014-02-01

    Long-term change of Earth's magnetic field (palaeomagnetic secular variation, PSV) during much of the last approximately 120 ka was recorded in cored sediment from the slope margin of the eastern Tyrrhenian Sea. The PSV record has been correlated to master curves of global palaeomagnetic field intensity and PSV records for western Europe. Tephrochronology and radiometric dating (14C and 40Ar/39Ar) have also been used to constrain the age of the PSV record. The combination of the new data with prior PSV and petrophysical data from the area provides a chronological framework for geological events such as large-scale submarine slumps, stratigraphic gaps and short-term changes in deposition rate on the continental margin. These latter changes are linked to the combined action of relative sea-level oscillations, climate events, and consequent variations in land exposure through time. Moreover, new data concerning the thickness and dispersal of Campanian Plain pyroclastic deposits in the marine setting enable volcanic-hazard evaluation. Finally, a pyroclastic deposit (tephra X-6) found offshore in the Southern Campanian marine environment was 40Ar/39Ar dated for the first time at 108.9 ± 1.8 ka BP.

  3. Re-Evaluating the Geological Evidence for Late Holocene Marine Incursion Events along the Guerrero Seismic Gap on the Pacific Coast of Mexico.

    PubMed

    Bianchette, Thomas A; McCloskey, Terrence A; Liu, Kam-Biu

    2016-01-01

    Despite the large number of tsunamis that impact Mexico's Pacific coast, stratigraphic studies focusing on geological impacts are scanty, making it difficult to assess the long-term risks for this vulnerable region. Surface samples and six cores were taken from Laguna Mitla near Acapulco to examine sedimentological and geochemical evidence for marine incursion events. Sediment cores collected from behind the beach barrier are dominated by intercalated layers of peat and inorganic sediments, mostly silt and clay, with little or no sand. Sand- and shell-rich clastic layers with high levels of sulfur, calcium, and strontium only occur adjacent to the relict beach ridge remnants near the center of the lagoon. With the exception of one thin fine sand layer, the absence of sand in the near-shore cores and the predominance of the terrigenous element titanium in the inorganic layers, evidently eroded from the surrounding hillslopes, suggests that these large-grained intervals do not represent episodic marine incursions, but rather were likely formed by the erosion and redeposition of older marine deposits derived from the beach ridge remnants when water levels were high. These results do not support the occurrence of a large tsunami event at Laguna Mitla during the Late Holocene.

  4. Re-Evaluating the Geological Evidence for Late Holocene Marine Incursion Events along the Guerrero Seismic Gap on the Pacific Coast of Mexico

    PubMed Central

    Bianchette, Thomas A.

    2016-01-01

    Despite the large number of tsunamis that impact Mexico’s Pacific coast, stratigraphic studies focusing on geological impacts are scanty, making it difficult to assess the long-term risks for this vulnerable region. Surface samples and six cores were taken from Laguna Mitla near Acapulco to examine sedimentological and geochemical evidence for marine incursion events. Sediment cores collected from behind the beach barrier are dominated by intercalated layers of peat and inorganic sediments, mostly silt and clay, with little or no sand. Sand- and shell-rich clastic layers with high levels of sulfur, calcium, and strontium only occur adjacent to the relict beach ridge remnants near the center of the lagoon. With the exception of one thin fine sand layer, the absence of sand in the near-shore cores and the predominance of the terrigenous element titanium in the inorganic layers, evidently eroded from the surrounding hillslopes, suggests that these large-grained intervals do not represent episodic marine incursions, but rather were likely formed by the erosion and redeposition of older marine deposits derived from the beach ridge remnants when water levels were high. These results do not support the occurrence of a large tsunami event at Laguna Mitla during the Late Holocene. PMID:27571270

  5. Rare earth elements content in geological samples from eastern desert, Egypt, determined by instrumental neutron activation analysis.

    PubMed

    El-Taher, A

    2010-09-01

    Twenty representative geological samples (tonalite, granodiorite, adamellite, syenogranite, rapakivi syenogranite, alkali feldspar granite and monzogranite) were collected from G. Kattar area in Eastern Desert, Egypt, for analysis by instrumental neutron activation as a sensitive nondestructive analytical tool for the determination of 14 rare earth elements (REEs) and to find out the following: (1) what information could be obtained about the REEs and distribution patterns of REEs in geological samples under investigation, (2) to estimate the accuracy, reproducibility and detection limit of the INAA method in case of the given samples. The samples were properly prepared together with standard reference material and simultaneously irradiated in a neutron flux of 7x10(11)n/cm(2)s in the TRIGA Mainz research reactor facilities. The gamma spectra were collected by an HPGe detector and the analysis was done by means of a computerized multichannel analyzer. The choice of the nuclear reaction, irradiation and decay times, and of the proper gamma radiation in counting are presented and discussed. The results are found to be in good agreement with certified values.

  6. A reevaluation of TDR propagation time determination in soils and geological media

    USDA-ARS?s Scientific Manuscript database

    Time domain reflectometry (TDR) is an established method for the determination of apparent dielectric permittivity and water content in soils. Using current waveform interpretation procedures, signal attenuation and variation in dielectric media properties along the transmission line can significant...

  7. Combined analysis of passive and active seismic measurements using additional geologic data for the determination of shallow subsurface structures

    NASA Astrophysics Data System (ADS)

    Horstmann, Tobias; Brüstle, Andrea; Spies, Thomas; Schlittenhardt, Jörg; Schmidt, Bernd

    2016-04-01

    A detailed knowledge of subsurface structure is essential for geotechnical projects and local seismic hazard analyses. Passive seismic methods like microtremor measurements are widely used in geotechnical practice, but limitations and developments are still in focus of scientific discussion. The presentation outlines microtremor measurements in the context of microzonation in the scale of districts or small communities. H/V measurements are used to identify zones with similar underground properties. Subsequently a shear wave velocity (Vs) depth profile for each zone is determined by array measurements at selected sites. To reduce possible uncertainties in dispersion curve analyses of passive array measurements and ambiguities within the inversion process, we conducted an additional active seismic experiment and included available geological information. The presented work is realized in the framework of the research project MAGS2 ("Microseismic Activity of Geothermal Systems") and deals with the determination of seismic hazard analysis at sites near deep geothermal power plants in Germany. The measurements were conducted in the Upper Rhine Graben (URG) and the Bavarian molasses, where geothermal power plants are in operation. The results of the H/V- and array-measurements in the region of Landau (URG) are presented and compared to known geological-tectonic structures. The H/V measurements show several zones with similar H/V-curves which indicate homogenous underground properties. Additionally to the passive seismic measurements an active refraction experiment was performed and evaluated using the MASW method („Multichannel Analysis of Surface Waves") to strengthen the determination of shear-wave-velocity depth profile. The dispersion curves for Rayleigh-waves of the active experiment support the Rayleigh-dispersion curves from passive measurements and therefore provide a valuable supplement. Furthermore, the Rayleigh-wave ellipticity was calculated to reduce

  8. Determination of indium in geological materials by electrothermal-atomization atomic absorption spectrometry with a tungsten-impregnated graphite furance

    USGS Publications Warehouse

    Zhou, L.; Chao, T.T.; Meier, A.L.

    1984-01-01

    The sample is fused with lithium metaborate and the melt is dissolved in 15% (v/v) hydrobromic acid. Iron(III) is reduced with ascorbic acid to avoid its coextraction with indium as the bromide into methyl isobutyl ketone. Impregnation of the graphite furnace with sodium tungstate, and the presence of lithium metaborate and ascorbic acid in the reaction medium improve the sensitivity and precision. The limits of determination are 0.025-16 mg kg-1 indium in the sample. For 22 geological reference samples containing more than 0.1 mg kg-1 indium, relative standard deviations ranged from 3.0 to 8.5% (average 5.7%). Recoveries of indium added to various samples ranged from 96.7 to 105.6% (average 100.2%). ?? 1984.

  9. Separation of climate- and geology-induced variations in the hydrological response of a regional karstified aquifer: determination of a geologic transfer function

    NASA Astrophysics Data System (ADS)

    Slimani, S.; Massei, N.; Dupont, J.-P.; Mesquita, J.; Laignel, B.

    2009-04-01

    Worldwide, karst hydrosystems represent a great potential in terms of water ressources. However, such heterogenous systems are characterized by a highly non-linear response to input signals. In the region of Upper Normandy (Northwestern France), where almost 100% of drinking water supply comes from ground water, the Chalk karst aquifer is characterized by the presence of a thick surficial formations cover which is unequally distributed over the area according to the regional geological context. This structural context also implies a significant spatial variability of the aquifer thickness. To assess the overall hydrologic variability of this aquifer, we use long-term hydraulic head and precipitation time series (20 years) to analyse their relationships according to such specific geological conditions. By continuous wavelet transform, the hydraulic head time series were found to exhibit long-term variations that represented a great amount of variance in some locations, what we could eventually relate to climate-induced oscillations. This was particularly the case of those locations where the aquifer thickness was important. The climate-induced oscillations found were of the order of 2-3-yr and 5-6-yr which would well correspond to some modes of oscillation linked to the positive/negative regimes of the North Atlantic Oscillation. In addition, the corresponding variations in hydrological time series exhibited a clear increase in the explanation of total variance from the early 90's up to the end of the series. In a second time, in order to assess the role of the geological medium in the precipitation/head relationship, we proposed to filter out those long-term spectral components inherent to climate fluctuations. This allowed identification of the head response to precipitation throughout the entire 20-yr period of study for short-term infra-annual time scales. Cross-correlation between the input and output signals after filtering out of long-term components showed

  10. Is our Future Written in the Geological Record of Oceanic Anoxic Events? The Calcareous Nannoplankton Perspective (Invited)

    NASA Astrophysics Data System (ADS)

    Erba, E.

    2013-12-01

    The topical emergence of climate change as a crucial issue for society and governments has urged the understanding of the future state of the planet within the context of increasing carbon dioxide concentrations. In the near future, the ocean's uptake of CO2 is expected to rapidly decline because of surface warming, increased vertical stratification, and slowed thermohaline circulation. The Anthropocene CO2 emissions are inferred to be the cause of global warming and alteration of ocean chemistry, triggering unknown responses of marine biota in terms of extinction, innovation and/or temporary adaptations. During the Mesozoic under excess CO2 and greenhouse conditions, the ocean became depleted of oxygen, promoting the burial of massive amounts of organic matter. These episodes are named Oceanic Anoxic Events (OAEs) and might provide guidance as to the response of marine biota to massive CO2 releases and how and at what rate pre-perturbation conditions are eventually restored. After over three decades of research on OAEs, an impressive amount of data has been generated: there is a general consensus on the role of Large Igneous Provinces (LIPs) inducing CO2 increases, greenhouse climate and profound variations in chemical, physical and trophic characteristics of the ocean. OAEs can be studied to decipher the complexity of drivers and of responses within and among different organisms to CO2 pulses, extreme warmth, weathering changes, ocean fertilization and acidification to add the long-term and large-scale prospective to investigations on current, very-short-term and local responses. In Jurassic and Cretaceous oceans, coccolithophores were already a most efficient carbonate-forming group and OAEs offer the opportunity of characterizing variations in their abundance, diversity, and morphology to trace ecological affinities and adaptations to oceanic ecosystem perturbations. We quantitatively investigated the Toarcian OAE, the early Aptian OAE1a and the latest

  11. High plasma omentin predicts cardiovascular events independently from the presence and extent of angiographically determined atherosclerosis.

    PubMed

    Saely, Christoph H; Leiherer, Andreas; Muendlein, Axel; Vonbank, Alexander; Rein, Philipp; Geiger, Kathrin; Malin, Cornelia; Drexel, Heinz

    2016-01-01

    No prospective data on the power of the adipocytokine omentin to predict cardiovascular events are available. We aimed at investigating i) the association of plasma omentin with cardiometabolic risk markers, ii) its association with angiographically determined coronary atherosclerosis, and iii) its power to predict cardiovascular events. We measured plasma omentin in 295 patients undergoing coronary angiography for the evaluation of established or suspected stable coronary artery disease (CAD), of whom 161 had significant CAD with coronary artery stenoses ≥50% and 134 did not have significant CAD. Over 3.5 years, 17.6% of our patients suffered cardiovascular events, corresponding to an annual event rate of 5.0%. At baseline, plasma omentin was not significantly associated with metabolic syndrome stigmata and did not differ significantly between patients with and subjects without significant CAD (17.2 ± 13.6 ng/ml vs. 17.5 ± 15.1 ng/ml; p = 0.783). Prospectively, however, cardiovascular event risk significantly increased over tertiles of omentin (12.1%, 13.8%, and 29.5%, for tertiles 1 through 3; ptrend = 0.003), and omentin as a continuous variable significantly predicted cardiovascular events after adjustment for age, gender, BMI, diabetes, hypertension, LDL cholesterol, HDL cholesterol, and smoking (standardized adjusted hazard ratio (HR) 1.41 [95% CI 1.16-1.72]; p < 0.001), as well as after additional adjustment for the presence and extent of significant CAD at baseline (HR 1.59 [95% CI 1.29-1.97, p < 0.001). From this first prospective evaluation of the cardiovascular risk associated with omentin we conclude that elevated plasma omentin significantly predicts cardiovascular events independently from the presence and extent of angiographically determined baseline CAD. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  12. Flame and flameless atomic-absorption determination of tellurium in geological materials

    USGS Publications Warehouse

    Chao, T.T.; Sanzolone, R.F.; Hubert, A.E.

    1978-01-01

    The sample is digested with a solution of hydrobromic acid and bromine and the excess of bromine is expelled. After dilution of the solution to approximately 3 M in hydrobromic acid, ascorbic acid is added to reduce iron(III) before extraction of tellurium into methyl isobutyl ketone (MIBK). An oxidizing air-acetylene flame is used to determine tellurium in the 0.1-20 ppm range. For samples containing 4-200 ppb of tellurium, a carbon-rod atomizer is used after the MIBK extract has been washed with 0.5 M hydrobromic acid to remove the residual iron. The flame procedure is useful for rapid preliminary monitoring, and the flameless procedure can determine tellurium at very low concentrations. ?? 1978.

  13. Determination of trace amounts of tin in geological materials by atomic absorption spectrometry

    USGS Publications Warehouse

    Welsch, E.P.; Chao, T.T.

    1976-01-01

    An atomic absorption method is described for the determination of traces of tin in rocks, soils, and stream sediments. A dried mixture of the sample and ammonium iodide is heated to volatilize tin tetraiodide -which is then dissolved in 5 % hydrochloric acid, extracted into TOPO-MIBK, and aspirated into a nitrous oxide-acetylene flame. The limit of determination is 2 p.p.m. tin and the relative standard deviation ranges from 2 to 14 %. Up to 20 % iron and 1000 p.p.m. Cu, Pb, Zn, Mn, Hg, Mo, V, or W in the sample do not interfere. As many as 50 samples can be easily analyzed per man-day. ?? 1976.

  14. Determination of Event-Dependent Depth of Closure for the South Florida Atlantic Coast Using Airborne Laser Bathymetry

    NASA Astrophysics Data System (ADS)

    Robertson, W.; Zhang, K.; Finkl, C.; Whitman, D.

    2007-12-01

    Depth of closure (DOC) is an important concept in coastal engineering that defines the seaward limit of significant net sediment transport along a wave-dominated sandy beach profile. Few surveys measured the DOC over large areas because traditional methods for measuring DOC are time consuming and cost prohibitive. With a dramatic increase in airborne laser bathymetric data in recent years, it has become possible to measure DOC over many kilometers. Reported here is a new method that identifies the DOC using airborne laser bathymetric (ALB) data. The horizontal location of the DOC was determined by differencing 2004 pre- and post-hurricane airborne laser data sets along Palm Beach, Broward, and Miami-Dade counties. Noise in the ALB data were approximately +/- 0.3 m, thus bathymetric variations greater than +/- 0.3 m were considered significant change. The seaward depth where change was less than +/- 0.3 m was interpreted as the DOC. The measured DOC was compared horizontally and vertically to DOC positions that were calculated based on wave data and to geomorphic units at 1046 locations spaced 100 m along the coastline. Calculated DOC values were on average within 2.8 m vertically to the measured DOC in the northern end of the study area. In the southern segment of the study area, however, the calculated DOC was on average deeper than the measured DOC. Small horizontal differences (90 m, on average) between geomorphic boundaries (rock outcrop, hardgrounds) and measured DOC suggest geologic control south of Hillsboro Inlet. Diabathic channel fields match the measured DOC to the north, with a vertical difference of 0.3 m and a horizontal difference of 161 m, on average. Because diabathic channels are hydrodynamically formed (hydromorphodynamic forms), the northern study area appears to be hydrodynamically controlled. Given the ALB data represent a before and after surface for the 2004 hurricane season, the DOC extracted from ALB data in this study is event

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

    NASA Astrophysics Data System (ADS)

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

    2016-12-01

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

  16. Determination of the parameters of plasticity models of geological media on the base of computer simulation

    NASA Astrophysics Data System (ADS)

    Astafurov, S. V.; Shilko, E. V.; Dimaki, A. V.; Psakhie, S. G.

    2016-11-01

    The paper is devoted to theoretical investigation of peculiarities of inelastic deformation of porous brittle materials in constrained conditions. The study was based on computer-aided simulation by movable cellular automaton method. Analysis of the simulation results allowed to estimate values of some rheological parameters of porous brittle materials and to determine the limits of applicability of Mises-Schleicher equation for description of the inelastic deformation of such materials under axial compression in constrained conditions.

  17. Determination of arsenic in geological materials by electrothermal atomic-absorption spectrometry after hydride generation

    USGS Publications Warehouse

    Sanzolone, R.F.; Chao, T.T.; Welsch, E.P.

    1979-01-01

    Rock and soil samples are decomposed with HClO4-HNO3; after further treatment, arsine is generated and absorbed in a dilute silver nitrate solution. Aliquots of this solution are injected into a carbon rod atomizer. Down to 1 ppm As in samples can be determined and there are no significant interferences, even from chromium in soils. Good results were obtained for geochemical reference samples. ?? 1979.

  18. Determination of elements in National Bureau of Standards' geological Standard Reference Materials by neutron activation analysis

    SciTech Connect

    Graham, C.C.; Glascock, M.D.; Carni, J.J.; Vogt, J.R.; Spalding, T.G.

    1982-08-01

    Instrumental neutron activation analysis (INAA) and prompt gamma neutron activation analysis (PGNAA) have been used to determine elemental concentrations in two recently issued National Bureau of Standards (NBS) Standard Reference Materials (SRM's). The results obtained are in good agreement with the certified and information values reported by NBS for those elements in each material for which comparisons are available. Average concentrations of 35 elements in SRM 278 obsidian rock and 32 elements in SRM 688 basalt rock are reported for comparison with results that may be obtained by other laboratories.

  19. Extreme event archived in the geological record of the Japan Trench: New results from R/V Sonne Cruise SO-251 towards establishing J-TRACK paleoseismology

    NASA Astrophysics Data System (ADS)

    Strasser, Michael; Kopf, Achim; Kanamatsu, Toshyia; Moernaut, Jasper; Ikehara, Ken; McHugh, Cecila

    2017-04-01

    Our perspective of subduction zonés earthquake magnitude and recurrence is limited by short historical records. Examining prehistoric extreme events preserved in the geological record is essential towards understanding large earthquakes and assessing the geohazard potential associated with such rare events. The research field of "subaquatic paleoseismology" is a promising approach to investigate deposits from the deep sea, where earthquakes leave traces preserved in stratigraphic succession. However, at present we lack comprehensive data set that allow conclusive distinctions between quality and completeness of the paleoseismic archives as they may relate to different sediment transport, erosion and deposition processes vs. variability of intrinsic seismogenic behavior across different segments. Initially building on what sedimentary deposits were generated from the 2011 Magnitude 9 Tohoku-oki earthquake, the Japan Trench is a promising study area to investigate earthquake-triggered sediment remobilization processes and how they become embedded in the stratigraphic record. Here we present new results from the recent R/V Sonne expedition SO251 that acquired a complete high-resolution bathymetric map of the trench axis and nearly 2000 km of subbottom Parasound profiles, covering the entire along-strike extent of the Japan Trench from 36° to 40.3° N, and groundtruthed by several nearly 10m long piston cores retrieved from the very deep waters (7 to 8 km below sea level): Several smaller submarine landslide (up to several 100's m of lateral extent) can be identified along the trench axis in the new bathymetric data set. These features were either not yet present, or not resolved in the lower-resolution bathymetric dataset acquired before 2011. Sub-bottom acoustic reflection data reveals striking, up to several meter thick, acoustically transparent bodies interbedded in the otherwise parallel reflection pattern of the trench fill basins, providing a temporal and

  20. Mathematical programming (MP) model to determine optimal transportation infrastructure for geologic CO2 storage in the Illinois basin

    NASA Astrophysics Data System (ADS)

    Rehmer, Donald E.

    Analysis of results from a mathematical programming model were examined to 1) determine the least cost options for infrastructure development of geologic storage of CO2 in the Illinois Basin, and 2) perform an analysis of a number of CO2 emission tax and oil price scenarios in order to implement development of the least-cost pipeline networks for distribution of CO2. The model, using mixed integer programming, tested the hypothesis of whether viable EOR sequestration sites can serve as nodal points or hubs to expand the CO2 delivery infrastructure to more distal locations from the emissions sources. This is in contrast to previous model results based on a point-to- point model having direct pipeline segments from each CO2 capture site to each storage sink. There is literature on the spoke and hub problem that relates to airline scheduling as well as maritime shipping. A large-scale ship assignment problem that utilized integer linear programming was run on Excel Solver and described by Mourao et al., (2001). Other literature indicates that aircraft assignment in spoke and hub routes can also be achieved using integer linear programming (Daskin and Panayotopoulos, 1989; Hane et al., 1995). The distribution concept is basically the reverse of the "tree and branch" type (Rothfarb et al., 1970) gathering systems for oil and natural gas that industry has been developing for decades. Model results indicate that the inclusion of hubs as variables in the model yields lower transportation costs for geologic carbon dioxide storage over previous models of point-to-point infrastructure geometries. Tabular results and GIS maps of the selected scenarios illustrate that EOR sites can serve as nodal points or hubs for distribution of CO2 to distal oil field locations as well as deeper saline reservoirs. Revenue amounts and capture percentages both show an improvement over solutions when the hubs are not allowed to come into the solution. Other results indicate that geologic

  1. Dimension determination of precursive stall events in a single stage high speed compressor

    NASA Astrophysics Data System (ADS)

    Bright, Michelle M.; Qammar, Helen K.; Hartley, Tom T.

    1996-06-01

    This paper presents a study of the dynamics for a single-stage, axial-flow, high speed compressor core, specifically, the NASA Lewis rotor stage 37. Due to the overall blading design for this advanced core compressor, each stage has considerable tip loading and higher speed than most compressor designs, thus, the compressor operates closer to the stall margin. The onset of rotating stall is explained as bifurcations in the dynamics of axial compressors. Data taken from the compressor during a rotating stall event is analyzed. Through the use of a box-assisted correlation dimension methodology, the attractor dimension is determined during the bifurcations leading to rotating stall. The intent of this study is to examine the behavior of precursive stall events so as to predict the entrance into rotating stall. This information may provide a better means to identify, avoid or control the undersireable event of rotating stall formation in high speed compressor cores.

  2. Dimension Determination of Precursive Stall Events in a Single Stage High Speed Compressor

    NASA Technical Reports Server (NTRS)

    Bright, Michelle M.; Qammar, Helen K.; Hartley, Tom T.

    1996-01-01

    This paper presents a study of the dynamics for a single-stage, axial-flow, high speed compressor core, specifically, the NASA Lewis rotor stage 37. Due to the overall blading design for this advanced core compressor, each stage has considerable tip loading and higher speed than most compressor designs, thus, the compressor operates closer to the stall margin. The onset of rotating stall is explained as bifurcations in the dynamics of axial compressors. Data taken from the compressor during a rotating stall event is analyzed. Through the use of a box-assisted correlation dimension methodology, the attractor dimension is determined during the bifurcations leading to rotating stall. The intent of this study is to examine the behavior of precursive stall events so as to predict the entrance into rotating stall. This information may provide a better means to identify, avoid or control the undesirable event of rotating stall formation in high speed compressor cores.

  3. Determination of thorium in geological materials by x-ray fluorescence spectrometry after anion exchange extraction

    SciTech Connect

    Roelandts, I.

    1983-08-01

    The exchange capacity of the resin was determined to be 1 m equiv of Th/g dry resin. Synthetic calibration standards of thorium were prepared over a large concentration range, for use as an independent method of calibration. The advantages and disadvantages of direct x-ray fluorescence analysis are discussed. The lower limit of detection has been calculated according to Currie's convention and was found to be equal to 13 ..mu..g of Th/250 mg of resin, sufficient for the range of concentrations found in Th bearing minerals and ores. Results using Canadian syenite rocks and a suite of South African reference minerals show that the proposed method appears to be relatively precise and accurate for exploration geochemistry. 1 figure, 2 tables.

  4. Geological events and Pliocene climate fluctuations explain the phylogeographical pattern of the cold water fish Rhynchocypris oxycephalus (Cypriniformes: Cyprinidae) in China.

    PubMed

    Yu, Dan; Chen, Ming; Tang, Qiongying; Li, Xiaojuan; Liu, Huanzhang

    2014-10-25

    Rhynchocypris oxycephalus is a cold water fish with a wide geographic distribution including the relatively warm temperate regions of southern China. It also occurs in second- and third-step geomorphic areas in China. Previous studies have postulated that high-altitude populations of R. oxycephalus in southern China are Quaternary glacial relics. In this study, we used the mitochondrial gene Cytb and the nuclear gene RAG2 to investigate the species phylogeographical patterns and to test two biogeographic hypotheses: (1) that divergence between lineages supports the three-step model and (2) climatic fluctuations during the Quaternary resulted in the present distribution in southern China. Phylogenetic analysis detected three major matrilines (A, B, and C); with matrilines B and C being further subdivided into two submatrilines. Based on genetic distances and morphological differences, matriline A potentially represents a cryptic subspecies. The geographic division between matrilines B and C coincided with the division of the second and third geomorphic steps in China, suggesting a historical vicariance event. Pliocene climatic fluctuations might have facilitated the southwards dispersal of R. oxycephalus in matriline C, with the subsequent warming resulting in its split into submatrilines C1 and C2, leaving submatriline C2 as a relic in southern China. Our study demonstrates that geological events (three steps orogenesis) and climate fluctuations during the Pliocene were important factors in shaping phylogeographical patterns in R. oxycephalus. Notably, no genetic diversity was detected in several populations, all of which possessed unique genotypes. This indicates the uniqueness of local populations and calls for a special conservation plan for the whole species at the population level.

  5. An integrated geochemical and geological approach for determining hydrocarbon generation-migration patterns: Central Gulf Coast Basin

    SciTech Connect

    Echols, J.B.; Zimmerman, R.K.; Goddard, D.A.

    1994-12-31

    New geochemical, geological, and well-production data indicate a Mesozoic hydrocarbon source for many younger reservoirs in central Louisiana and southwest Mississippi. A Jurassic source has been determined for several Cretaceous reservoirs in oil and gas fields of northeast Louisiana. The characteristic Wilcox, Sparta, and Frio biomarker, Bisnorhopane, identified in Austin Chalk oils from southwest Mississippi, links these Mesozoic and Tertiary oils. Cross-plots of {delta}{sup 13}C{sub AROM} versus {delta}{sup 13}C{sub SAT} indicate an Upper Jurassic (Smackover) and Lower Cretaceous source for certain Upper Cretaceous and Tertiary oils. However, the pristane/C{sub 17} ratio versus {delta}{sup 13}C{sub SAT} cross-plot indicates Wilcox and Sparta oils are heavily biodegraded Mesozoic (Lower Cretaceous) oils. There is an absence of gas accumulations in central Louisiana and southwest Mississippi in Midway, Wilcox, and Sparta reservoirs updip from coeval gas-prone source rocks. This is an indication of (1) a sealing regional fault system and/or stratigraphic migration barrier paralleling the Paleocene-Eocene shelf edge or (2) an earlier selective escape via vertical migration pathways. Vertical migration of hydrocarbons in northeast Louisiana, central Louisiana, and southwest Mississippi was accomplished primarily through fracture systems caused by wrench faulting; to the south and west, salt tectonics and related normal faulting played significant roles in the process. In onshore and offshore south Louisiana, normal faulting and salt-related tectonics created primary migration pathways. Regional hydrocarbon generation-migration patterns differ conceptually from those illustrated in previous models employing long-range migration based primarily on geochemical considerations. This new interpretation integrates geochemical, geological, and production data useful in identifying new exploration plays in north and central Louisiana and in southwest Mississippi.

  6. An integrated geochemical and geological approach for determining hydrocarbon generation-migration patterns: Central Gulf Coast Basin

    SciTech Connect

    Echols, J.B.; Zimmerman, R.K.; Goddard, D.A.

    1994-09-01

    New geochemical, geological, and well-production data indicate a Mesozoic hydrocarbon source for many younger reservoirs in central Louisiana and southwest Mississippi. A Jurassic source has been determined for several oil and gas fields in northeast Louisiana. The characteristic Wilcox and Sparta biomarker, bisnorhopane, identified in Austin Chalk oils from southwest Mississippi, links these Mesozoic and Tertiary oils. Cross-plots of {delta}{sup 13}C{sub AROM} vs. {delta}{sup 13}C{sub SAT} indicate a lower Cretaceous source for certain upper Cretaceous and Tertiary oils, while crossplots of pristane/nC{sub 17} ratio vs. {delta}{sup 13}C{sub SAT} crossplots indicate that Wilcox and Sparta oils are heavily biodegraded Mesozoic (lower Cretaceous) oils. There is an absence of gas accumulations in central Louisiana and southwest Mississippi in Midway, Wilcox, and Sparta reservoirs updip from coeval gas-prone source rocks. This is an indication of a sealing regional fault system and/or stratigraphic migration barrier paralleling the Paleocene-Eocene shelf edge. Vertical migration of hydrocarbons in northeast Louisiana, central Louisiana, and southwest Mississippi was accomplished primarily through fracture systems caused by wrench faulting; to the south and west, salt tectonics and related normal faulting played significant roles in the process. In onshore and offshore south Louisiana, normal faulting and salt-related tectonics created primary migration pathways. Regional hydrocarbon generation-migration patterns differ conceptually from those illustrated in previous models employing long-range migration based primarily on geochemical considerations. This new interpretation integrates geochemical, geological, and production data especially useful in identifying new exploration plays in north and central Louisiana and in southwest Mississippi.

  7. Determination of Vertical Borehole and Geological Formation Properties using the Crossed Contour Method.

    PubMed

    Leyde, Brian P; Klein, Sanford A; Nellis, Gregory F; Skye, Harrison

    2017-03-01

    This paper presents a new method called the Crossed Contour Method for determining the effective properties (borehole radius and ground thermal conductivity) of a vertical ground-coupled heat exchanger. The borehole radius is used as a proxy for the overall borehole thermal resistance. The method has been applied to both simulated and experimental borehole Thermal Response Test (TRT) data using the Duct Storage vertical ground heat exchanger model implemented in the TRansient SYstems Simulation software (TRNSYS). The Crossed Contour Method generates a parametric grid of simulated TRT data for different combinations of borehole radius and ground thermal conductivity in a series of time windows. The error between the average of the simulated and experimental bore field inlet and outlet temperatures is calculated for each set of borehole properties within each time window. Using these data, contours of the minimum error are constructed in the parameter space of borehole radius and ground thermal conductivity. When all of the minimum error contours for each time window are superimposed, the point where the contours cross (intersect) identifies the effective borehole properties for the model that most closely represents the experimental data in every time window and thus over the entire length of the experimental data set. The computed borehole properties are compared with results from existing model inversion methods including the Ground Property Measurement (GPM) software developed by Oak Ridge National Laboratory, and the Line Source Model.

  8. Determinants of the Price of High-Tech Metals: An Event Study

    SciTech Connect

    Wanner, Markus Gaugler, Tobias; Gleich, Benedikt; Rathgeber, Andreas

    2015-06-15

    The growing demand for high-tech products has resulted in strong growth in demand for certain minor metals. In combination with production concentrated in China, this caused strong and unpredicted price movements in recent years. As a result, manufacturing companies have to cope with additional risks. However, the detailed reasons for the price development are only partially understood. Therefore, we analyzed empirically which determinants can be assigned to price movements and performed an event study on the high-tech metals neodymium, indium, and gallium. Based on our dataset of news items, we were able to find coinciding events to almost 90% of all price jumps (recall). We showed that if any information about these events occurred with a probability of over 50% there would also be a price jump within 10 days (precision). However, the classical set of price determinants has to be extended for these specific markets, as we found unorthodox factors like holidays or weather that may be indicators for price movements. Therefore, we hope that our study supports industry for instance in performing more informed short-term planning of metals purchasing based on information about specific events.

  9. Determining the parameters of high amplification microlensing events by means of statistical machine learning techniques

    NASA Astrophysics Data System (ADS)

    Fedorova, Elena

    2017-06-01

    Strong gravitational microlensing (GM) events provide us a possibility to determine both the parameters of microlensed source and microlens. GM can be an important clue to understand the nature of dark matter on comparably small spatial and mass scales (i.e. substructure), especially when speaking about the combination of astrometrical and photometrical data about high amplification microlensing events (HAME). In the same time, fitting of HAME lightcurves of microlensed sources is quite time-consuming process. That is why we test here the possibility to apply the statistical machine learning techniques to determine the source and microlens parameters for the set of HAME lightcurves, using the simulated set of amplification curves of sources microlensed by point masses and clumps of DM with various density profiles.

  10. [Determination of Sb and Bi in 24 international geological reference materials by using pressurized acid digestion-ICP-MS].

    PubMed

    Hu, Zhao-chu; Gao, Shan; Liu, Xiao-ming; Yuan, Hong-lin; Liu, Ye; Diwu, Chun-rong

    2007-12-01

    The authors studied in detail the memory effect of Bi, Sb, As and Te in ICP-MS. The produced memory effects of these element were in the order of Bi>Sb>Te>As. Bi was seriously adsorbed by the polypropylene sample storing bottle and the sample introduction system in the low nitric acid medium (0.01%-1% HNO3). The washout effect of 0.1% HF was found to be better than those of 6% HNO3 and 0.1% HClO4. Under the given experiment conditions, the instrumental limit of detection was 0.001 and 0.0001 ng x mL(-1) for Sb and Bi, respectively. The authors report the determination of Sb and Bi in 24 international geological reference materials by using pressurized acid digestion-ICP-MS (including AGV-2, BHVO-2, BCR-2, etc.). Most of the results were found to be in reasonable agreement with the reported values in the literature. The authors' determined values of Sb for GSR-1 (granite; 0.30 microg x g(-1)) and JP-1 (peridotite; 0.045 microg x g(-1)) are obviously higher than those reported values. This is attributed to the efficient pressurized acid digestion, which is generally much more efficient than conventional wet digestions for insoluble minerals.

  11. Determining the significance of associations between two series of discrete events : bootstrap methods /

    SciTech Connect

    Niehof, Jonathan T.; Morley, Steven K.

    2012-01-01

    We review and develop techniques to determine associations between series of discrete events. The bootstrap, a nonparametric statistical method, allows the determination of the significance of associations with minimal assumptions about the underlying processes. We find the key requirement for this method: one of the series must be widely spaced in time to guarantee the theoretical applicability of the bootstrap. If this condition is met, the calculated significance passes a reasonableness test. We conclude with some potential future extensions and caveats on the applicability of these methods. The techniques presented have been implemented in a Python-based software toolkit.

  12. On the determination of iridium in diverse geological samples employing HPGe-coincidence/NaI(Tl)-anticoincidence spectrometry

    NASA Technical Reports Server (NTRS)

    Murali, A. V.; Parekh, P. P.; Cumming, J. B.

    1990-01-01

    This paper reports the Ir content of a variety of geological samples determined by the high-purity Ge-coincidence/NaI(Tl)-anticoincidence gamma-ray spectrometry (henceforth referred to as coincidence/anticoincidence technique) and by the conventional INAA. The advantages of this technique are: (1) the Ir content of the samples is obtained (ppm to a fraction of ppb ranges) not only by the 468.1 keV peak as in the conventional INAA but also by the 784.6 keV and 920.9 keV sum peaks, which gives more confidence in the values obtained; and (2) it is well suited for the samples with high Compton background for which it is difficult to measure the Ir content by the conventional INAA technique. The practical sensitivity of this technique depends on the sample matrix. Under present experimental conditions, it varied from 0.1 ng for Mn nodules and 0.004 ng for Libyan Desert Glass. Iridium values obtained on small (about 1 microg) olivine grains demonstrate the potential application of this new technique to microsamples. The principle and methodology of this new technique as well as its advantages and disadvantages over the conventional INAA are discussed.

  13. On the determination of iridium in diverse geological samples employing HPGe-coincidence/NaI(Tl)-anticoincidence spectrometry

    NASA Technical Reports Server (NTRS)

    Murali, A. V.; Parekh, P. P.; Cumming, J. B.

    1990-01-01

    This paper reports the Ir content of a variety of geological samples determined by the high-purity Ge-coincidence/NaI(Tl)-anticoincidence gamma-ray spectrometry (henceforth referred to as coincidence/anticoincidence technique) and by the conventional INAA. The advantages of this technique are: (1) the Ir content of the samples is obtained (ppm to a fraction of ppb ranges) not only by the 468.1 keV peak as in the conventional INAA but also by the 784.6 keV and 920.9 keV sum peaks, which gives more confidence in the values obtained; and (2) it is well suited for the samples with high Compton background for which it is difficult to measure the Ir content by the conventional INAA technique. The practical sensitivity of this technique depends on the sample matrix. Under present experimental conditions, it varied from 0.1 ng for Mn nodules and 0.004 ng for Libyan Desert Glass. Iridium values obtained on small (about 1 microg) olivine grains demonstrate the potential application of this new technique to microsamples. The principle and methodology of this new technique as well as its advantages and disadvantages over the conventional INAA are discussed.

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

    ERIC Educational Resources Information Center

    Nicholas, Frank W.

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

  15. Contextual determinants of condom use among female sex exchangers in East Harlem, NYC: an event analysis.

    PubMed

    McMahon, James M; Tortu, Stephanie; Pouget, Enrique R; Hamid, Rahul; Neaigus, Alan

    2006-11-01

    Recent studies have revealed a variety of contexts involving HIV risk behaviors among women who exchange sex for money or drugs. Event analysis was used to identify the individual, relationship, and contextual factors that contribute to these high-risk sex exchange practices. Analyses were conducted on data obtained from 155 drug-using women who reported details of their most recent sex exchange event with male clients. The majority of sex exchange encounters (78%) involved consistent condom use. In multivariable analysis, protective behavior was associated primarily with situational and relationship variables, such as exchange location, substance use, sexual practices, and respondent/client discussion and control. In order to inform HIV prevention programs targeted to women sex exchangers, further research is needed on the contextual determinants of risk, especially with regard to condom-use negotiation and factors involving substance use that adversely affect women's ability to manage protective behavior in the context of sex exchange.

  16. An Improved Method for Seismic Event Depth and Moment Tensor Determination: CTBT Related Application

    NASA Astrophysics Data System (ADS)

    Stachnik, J.; Rozhkov, M.; Baker, B.

    2016-12-01

    According to the Protocol to CTBT, International Data Center is required to conduct expert technical analysis and special studies to improve event parameters and assist State Parties in identifying the source of specific event. Determination of seismic event source mechanism and its depth is a part of these tasks. It is typically done through a strategic linearized inversion of the waveforms for a complete or subset of source parameters, or similarly defined grid search through precomputed Greens Functions created for particular source models. We show preliminary results using the latter approach from an improved software design and applied on a moderately powered computer. In this development we tried to be compliant with different modes of CTBT monitoring regime and cover wide range of source-receiver distances (regional to teleseismic), resolve shallow source depths, provide full moment tensor solution based on body and surface waves recordings, be fast to satisfy both on-demand studies and automatic processing and properly incorporate observed waveforms and any uncertainties a priori as well as accurately estimate posteriori uncertainties. Implemented HDF5 based Green's Functions pre-packaging allows much greater flexibility in utilizing different software packages and methods for computation. Further additions will have the rapid use of Instaseis/AXISEM full waveform synthetics added to a pre-computed GF archive. Along with traditional post processing analysis of waveform misfits through several objective functions and variance reduction, we follow a probabilistic approach to assess the robustness of moment tensor solution. In a course of this project full moment tensor and depth estimates are determined for DPRK 2009, 2013 and 2016 events and shallow earthquakes using a new implementation of waveform fitting of teleseismic P waves. A full grid search over the entire moment tensor space is used to appropriately sample all possible solutions. A recent method by

  17. Determination of the event collision time with the ALICE detector at the LHC

    NASA Astrophysics Data System (ADS)

    Adam, J.; Adamová, D.; Aggarwal, M. M.; Aglieri Rinella, G.; Agnello, M.; Agrawal, N.; Ahammed, Z.; Ahmad, S.; Ahn, S. U.; Aiola, S.; Akindinov, A.; Alam, S. N.; Albuquerque, D. S. D.; Aleksandrov, D.; Alessandro, B.; Alexandre, D.; Alfaro Molina, R.; Alici, A.; Alkin, A.; Alme, J.; Alt, T.; Altinpinar, S.; Altsybeev, I.; Alves Garcia Prado, C.; An, M.; Andrei, C.; Andrews, H. A.; Andronic, A.; Anguelov, V.; Anson, C.; Antičić, T.; Antinori, F.; Antonioli, P.; Anwar, R.; Aphecetche, L.; Appelshäuser, H.; Arcelli, S.; Arnaldi, R.; Arnold, O. W.; Arsene, I. C.; Arslandok, M.; Audurier, B.; Augustinus, A.; Averbeck, R.; Azmi, M. D.; Badalà, A.; Baek, Y. W.; Bagnasco, S.; Bailhache, R.; Bala, R.; Balasubramanian, S.; Baldisseri, A.; Baral, R. C.; Barbano, A. M.; Barbera, R.; Barile, F.; Barnaföldi, G. G.; Barnby, L. S.; Barret, V.; Bartalini, P.; Barth, K.; Bartke, J.; Bartsch, E.; Basile, M.; Bastid, N.; Basu, S.; Bathen, B.; Batigne, G.; Batista Camejo, A.; Batyunya, B.; Batzing, P. C.; Bearden, I. G.; Beck, H.; Bedda, C.; Behera, N. K.; Belikov, I.; Bellini, F.; Bello Martinez, H.; Bellwied, R.; Beltran, L. G. E.; Belyaev, V.; Bencedi, G.; Beole, S.; Bercuci, A.; Berdnikov, Y.; Berenyi, D.; Bertens, R. A.; Berzano, D.; Betev, L.; Bhasin, A.; Bhat, I. R.; Bhati, A. K.; Bhattacharjee, B.; Bhom, J.; Bianchi, L.; Bianchi, N.; Bianchin, C.; Bielčík, J.; Bielčíková, J.; Bilandzic, A.; Biro, G.; Biswas, R.; Biswas, S.; Bjelogrlic, S.; Blair, J. T.; Blau, D.; Blume, C.; Bock, F.; Bogdanov, A.; Boldizsár, L.; Bombara, M.; Bonora, M.; Book, J.; Borel, H.; Borissov, A.; Borri, M.; Botta, E.; Bourjau, C.; Braun-Munzinger, P.; Bregant, M.; Broker, T. A.; Browning, T. A.; Broz, M.; Brucken, E. J.; Bruna, E.; Bruno, G. E.; Budnikov, D.; Buesching, H.; Bufalino, S.; Buhler, P.; Buitron, S. A. I.; Buncic, P.; Busch, O.; Buthelezi, Z.; Butt, J. B.; Buxton, J. T.; Cabala, J.; Caffarri, D.; Caines, H.; Caliva, A.; Calvo Villar, E.; Camerini, P.; Carena, F.; Carena, W.; Carnesecchi, F.; Castillo Castellanos, J.; Castro, A. J.; Casula, E. A. R.; Ceballos Sanchez, C.; Cepila, J.; Cerello, P.; Cerkala, J.; Chang, B.; Chapeland, S.; Chartier, M.; Charvet, J. L.; Chattopadhyay, S.; Chattopadhyay, S.; Chauvin, A.; Chelnokov, V.; Cherney, M.; Cheshkov, C.; Cheynis, B.; Chibante Barroso, V.; Chinellato, D. D.; Cho, S.; Chochula, P.; Choi, K.; Chojnacki, M.; Choudhury, S.; Christakoglou, P.; Christensen, C. H.; Christiansen, P.; Chujo, T.; Chung, S. U.; Cicalo, C.; Cifarelli, L.; Cindolo, F.; Cleymans, J.; Colamaria, F.; Colella, D.; Collu, A.; Colocci, M.; Conesa Balbastre, G.; Conesa del Valle, Z.; Connors, M. E.; Contreras, J. G.; Cormier, T. M.; Corrales Morales, Y.; Cortés Maldonado, I.; Cortese, P.; Cosentino, M. R.; Costa, F.; Crkovská, J.; Crochet, P.; Cruz Albino, R.; Cuautle, E.; Cunqueiro, L.; Dahms, T.; Dainese, A.; Danisch, M. C.; Danu, A.; Das, D.; Das, I.; Das, S.; Dash, A.; Dash, S.; De, S.; De Caro, A.; de Cataldo, G.; de Conti, C.; de Cuveland, J.; De Falco, A.; De Gruttola, D.; De Marco, N.; De Pasquale, S.; De Souza, R. D.; Deisting, A.; Deloff, A.; Deplano, C.; Dhankher, P.; Di Bari, D.; Di Mauro, A.; Di Nezza, P.; Di Ruzza, B.; Diaz Corchero, M. A.; Dietel, T.; Dillenseger, P.; Divià, R.; Djuvsland, Ø.; Dobrin, A.; Domenicis Gimenez, D.; Dönigus, B.; Dordic, O.; Drozhzhova, T.; Dubey, A. K.; Dubla, A.; Ducroux, L.; Duggal, A. K.; Dupieux, P.; Ehlers, R. J.; Elia, D.; Endress, E.; Engel, H.; Epple, E.; Erazmus, B.; Erhardt, F.; Espagnon, B.; Esumi, S.; Eulisse, G.; Eum, J.; Evans, D.; Evdokimov, S.; Eyyubova, G.; Fabbietti, L.; Fabris, D.; Faivre, J.; Fantoni, A.; Fasel, M.; Feldkamp, L.; Feliciello, A.; Feofilov, G.; Ferencei, J.; Fernández Téllez, A.; Ferreiro, E. G.; Ferretti, A.; Festanti, A.; Feuillard, V. J. G.; Figiel, J.; Figueredo, M. A. S.; Filchagin, S.; Finogeev, D.; Fionda, F. M.; Fiore, E. M.; Floris, M.; Foertsch, S.; Foka, P.; Fokin, S.; Fragiacomo, E.; Francescon, A.; Francisco, A.; Frankenfeld, U.; Fronze, G. G.; Fuchs, U.; Furget, C.; Furs, A.; Fusco Girard, M.; Gaardhøje, J. J.; Gagliardi, M.; Gago, A. M.; Gajdosova, K.; Gallio, M.; Galvan, C. D.; Gangadharan, D. R.; Ganoti, P.; Gao, C.; Garabatos, C.; Garcia-Solis, E.; Garg, K.; Garg, P.; Gargiulo, C.; Gasik, P.; Gauger, E. F.; Gay Ducati, M. B.; Germain, M.; Ghosh, P.; Ghosh, S. K.; Gianotti, P.; Giubellino, P.; Giubilato, P.; Gladysz-Dziadus, E.; Glässel, P.; Goméz Coral, D. M.; Gomez Ramirez, A.; Gonzalez, A. S.; Gonzalez, V.; González-Zamora, P.; Gorbunov, S.; Görlich, L.; Gotovac, S.; Grabski, V.; Graczykowski, L. K.; Graham, K. L.; Greiner, L.; Grelli, A.; Grigoras, C.; Grigoriev, V.; Grigoryan, A.; Grigoryan, S.; Grion, N.; Gronefeld, J. M.; Grosse-Oetringhaus, J. F.; Grosso, R.; Gruber, L.; Guber, F.; Guernane, R.; Guerzoni, B.; Gulbrandsen, K.; Gunji, T.; Gupta, A.; Gupta, R.; Guzman, I. B.; Haake, R.; Hadjidakis, C.; Hamagaki, H.; Hamar, G.; Hamon, J. C.; Harris, J. W.; Harton, A.; Hatzifotiadou, D.; Hayashi, S.; Heckel, S. T.; Hellbär, E.; Helstrup, H.; Herghelegiu, A.; Herrera Corral, G.; Herrmann, F.; Hess, B. A.; Hetland, K. F.; Hillemanns, H.; Hippolyte, B.; Hladky, J.; Horak, D.; Hosokawa, R.; Hristov, P.; Hughes, C.; Humanic, T. J.; Hussain, N.; Hussain, T.; Hutter, D.; Hwang, D. S.; Ilkaev, R.; Inaba, M.; Ippolitov, M.; Irfan, M.; Isakov, V.; Islam, M. S.; Ivanov, M.; Ivanov, V.; Izucheev, V.; Jacak, B.; Jacazio, N.; Jacobs, P. M.; Jadhav, M. B.; Jadlovska, S.; Jadlovsky, J.; Jahnke, C.; Jakubowska, M. J.; Janik, M. A.; Jayarathna, P. H. S. Y.; Jena, C.; Jena, S.; Jimenez Bustamante, R. T.; Jones, P. G.; Jusko, A.; Kalinak, P.; Kalweit, A.; Kang, J. H.; Kaplin, V.; Kar, S.; Karasu Uysal, A.; Karavichev, O.; Karavicheva, T.; Karayan, L.; Karpechev, E.; Kebschull, U.; Keidel, R.; Keijdener, D. L. D.; Keil, M.; Mohisin Khan, M.; Khan, P.; Khan, S. A.; Khanzadeev, A.; Kharlov, Y.; Khatun, A.; Khuntia, A.; Kileng, B.; Kim, D. W.; Kim, D. J.; Kim, D.; Kim, H.; Kim, J. S.; Kim, J.; Kim, M.; Kim, M.; Kim, S.; Kim, T.; Kirsch, S.; Kisel, I.; Kiselev, S.; Kisiel, A.; Kiss, G.; Klay, J. L.; Klein, C.; Klein, J.; Klein-Bösing, C.; Klewin, S.; Kluge, A.; Knichel, M. L.; Knospe, A. G.; Kobdaj, C.; Kofarago, M.; Kollegger, T.; Kolojvari, A.; Kondratiev, V.; Kondratyeva, N.; Kondratyuk, E.; Konevskikh, A.; Kopcik, M.; Kour, M.; Kouzinopoulos, C.; Kovalenko, O.; Kovalenko, V.; Kowalski, M.; Koyithatta Meethaleveedu, G.; Králik, I.; Kravčáková, A.; Krivda, M.; Krizek, F.; Kryshen, E.; Krzewicki, M.; Kubera, A. M.; Kučera, V.; Kuhn, C.; Kuijer, P. G.; Kumar, A.; Kumar, J.; Kumar, L.; Kumar, S.; Kundu, S.; Kurashvili, P.; Kurepin, A.; Kurepin, A. B.; Kuryakin, A.; Kushpil, S.; Kweon, M. J.; Kwon, Y.; La Pointe, S. L.; La Rocca, P.; Lagana Fernandes, C.; Lakomov, I.; Langoy, R.; Lapidus, K.; Lara, C.; Lardeux, A.; Lattuca, A.; Laudi, E.; Lazaridis, L.; Lea, R.; Leardini, L.; Lee, S.; Lehas, F.; Lehner, S.; Lehrbach, J.; Lemmon, R. C.; Lenti, V.; Leogrande, E.; León Monzón, I.; Lévai, P.; Li, S.; Li, X.; Lien, J.; Lietava, R.; Lindal, S.; Lindenstruth, V.; Lippmann, C.; Lisa, M. A.; Ljunggren, H. M.; Llope, W.; Lodato, D. F.; Loenne, P. I.; Loginov, V.; Loizides, C.; Lopez, X.; López Torres, E.; Lowe, A.; Luettig, P.; Lunardon, M.; Luparello, G.; Lupi, M.; Lutz, T. H.; Maevskaya, A.; Mager, M.; Mahajan, S.; Mahmood, S. M.; Maire, A.; Majka, R. D.; Malaev, M.; Maldonado Cervantes, I.; Malinina, L.; Mal'Kevich, D.; Malzacher, P.; Mamonov, A.; Manko, V.; Manso, F.; Manzari, V.; Mao, Y.; Marchisone, M.; Mareš, J.; Margagliotti, G. V.; Margotti, A.; Margutti, J.; Marín, A.; Markert, C.; Marquard, M.; Martin, N. A.; Martinengo, P.; Martínez, M. I.; Martínez García, G.; Martinez Pedreira, M.; Mas, A.; Masciocchi, S.; Masera, M.; Masoni, A.; Mastroserio, A.; Matyja, A.; Mayer, C.; Mazer, J.; Mazzilli, M.; Mazzoni, M. A.; Meddi, F.; Melikyan, Y.; Menchaca-Rocha, A.; Meninno, E.; Mercado Pérez, J.; Meres, M.; Mhlanga, S.; Miake, Y.; Mieskolainen, M. M.; Mikhaylov, K.; Milano, L.; Milosevic, J.; Mischke, A.; Mishra, A. N.; Mishra, T.; Miśkowiec, D.; Mitra, J.; Mitu, C. M.; Mohammadi, N.; Mohanty, B.; Molnar, L.; Montes, E.; Moreira De Godoy, D. A.; Moreno, L. A. P.; Moretto, S.; Morreale, A.; Morsch, A.; Muccifora, V.; Mudnic, E.; Mühlheim, D.; Muhuri, S.; Mukherjee, M.; Mulligan, J. D.; Munhoz, M. G.; Münning, K.; Munzer, R. H.; Murakami, H.; Murray, S.; Musa, L.; Musinsky, J.; Myers, C. J.; Naik, B.; Nair, R.; Nandi, B. K.; Nania, R.; Nappi, E.; Naru, M. U.; Natal da Luz, H.; Nattrass, C.; Navarro, S. R.; Nayak, K.; Nayak, R.; Nayak, T. K.; Nazarenko, S.; Nedosekin, A.; Negrao De Oliveira, R. A.; Nellen, L.; Ng, F.; Nicassio, M.; Niculescu, M.; Niedziela, J.; Nielsen, B. S.; Nikolaev, S.; Nikulin, S.; Nikulin, V.; Noferini, F.; Nomokonov, P.; Nooren, G.; Noris, J. C. C.; Norman, J.; Nyanin, A.; Nystrand, J.; Oeschler, H.; Oh, S.; Ohlson, A.; Okubo, T.; Olah, L.; Oleniacz, J.; Oliveira Da Silva, A. C.; Oliver, M. H.; Onderwaater, J.; Oppedisano, C.; Orava, R.; Oravec, M.; Ortiz Velasquez, A.; Oskarsson, A.; Otwinowski, J.; Oyama, K.; Ozdemir, M.; Pachmayer, Y.; Pacik, V.; Pagano, D.; Pagano, P.; Paić, G.; Pal, S. K.; Palni, P.; Pan, J.; Pandey, A. K.; Papikyan, V.; Pappalardo, G. S.; Pareek, P.; Park, J.; Park, W. J.; Parmar, S.; Passfeld, A.; Paticchio, V.; Patra, R. N.; Paul, B.; Pei, H.; Peitzmann, T.; Peng, X.; Pereira Da Costa, H.; Peresunko, D.; Perez Lezama, E.; Peskov, V.; Pestov, Y.; Petráček, V.; Petrov, V.; Petrovici, M.; Petta, C.; Piano, S.; Pikna, M.; Pillot, P.; Pimentel, L. O. D. L.; Pinazza, O.; Pinsky, L.; Piyarathna, D. B.; Płoskoń, M.; Planinic, M.; Pluta, J.; Pochybova, S.; Podesta-Lerma, P. L. M.; Poghosyan, M. G.; Polichtchouk, B.; Poljak, N.; Poonsawat, W.; Pop, A.; Poppenborg, H.; Porteboeuf-Houssais, S.; Porter, J.; Pospisil, J.; Pozdniakov, V.; Prasad, S. K.; Preghenella, R.; Prino, F.; Pruneau, C. A.; Pshenichnov, I.; Puccio, M.; Puddu, G.; Pujahari, P.; Punin, V.; Putschke, J.; Qvigstad, H.; Rachevski, A.; Raha, S.; Rajput, S.; Rak, J.; Rakotozafindrabe, A.; Ramello, L.; Rami, F.; Rana, D. B.; Raniwala, R.; Raniwala, S.; Räsänen, S. S.; Rascanu, B. T.; Rathee, D.; Ratza, V.; Ravasenga, I.; Read, K. F.; Redlich, K.; Rehman, A.; Reichelt, P.; Reidt, F.; Ren, X.; Renfordt, R.; Reolon, A. R.; Reshetin, A.; Reygers, K.; Riabov, V.; Ricci, R. A.; Richert, T.; Richter, M.; Riedler, P.; Riegler, W.; Riggi, F.; Ristea, C.; Rodríguez Cahuantzi, M.; Røed, K.; Rogochaya, E.; Rohr, D.; Röhrich, D.; Ronchetti, F.; Ronflette, L.; Rosnet, P.; Rossi, A.; Roukoutakis, F.; Roy, A.; Roy, C.; Roy, P.; Rubio Montero, A. J.; Rui, R.; Russo, R.; Ryabinkin, E.; Ryabov, Y.; Rybicki, A.; Saarinen, S.; Sadhu, S.; Sadovsky, S.; Šafařík, K.; Sahlmuller, B.; Sahoo, B.; Sahoo, P.; Sahoo, R.; Sahoo, S.; Sahu, P. K.; Saini, J.; Sakai, S.; Saleh, M. A.; Salzwedel, J.; Sambyal, S.; Samsonov, V.; Sandoval, A.; Sano, M.; Sarkar, D.; Sarkar, N.; Sarma, P.; Sas, M. H. P.; Scapparone, E.; Scarlassara, F.; Scharenberg, R. P.; Schiaua, C.; Schicker, R.; Schmidt, C.; Schmidt, H. R.; Schmidt, M.; Schukraft, J.; Schutz, Y.; Schwarz, K.; Schweda, K.; Scioli, G.; Scomparin, E.; Scott, R.; Šefčík, M.; Seger, J. E.; Sekiguchi, Y.; Sekihata, D.; Selyuzhenkov, I.; Senosi, K.; Senyukov, S.; Serradilla, E.; Sett, P.; Sevcenco, A.; Shabanov, A.; Shabetai, A.; Shadura, O.; Shahoyan, R.; Shangaraev, A.; Sharma, A.; Sharma, A.; Sharma, M.; Sharma, M.; Sharma, N.; Sheikh, A. I.; Shigaki, K.; Shou, Q.; Shtejer, K.; Sibiriak, Y.; Siddhanta, S.; Sielewicz, K. M.; Siemiarczuk, T.; Silvermyr, D.; Silvestre, C.; Simatovic, G.; Simonetti, G.; Singaraju, R.; Singh, R.; Singhal, V.; Sinha, T.; Sitar, B.; Sitta, M.; Skaali, T. B.; Slupecki, M.; Smirnov, N.; Snellings, R. J. M.; Snellman, T. W.; Song, J.; Song, M.; Song, Z.; Soramel, F.; Sorensen, S.; Sozzi, F.; Spiriti, E.; Sputowska, I.; Srivastava, B. K.; Stachel, J.; Stan, I.; Stankus, P.; Stenlund, E.; Steyn, G.; Stiller, J. H.; Stocco, D.; Strmen, P.; Suaide, A. A. P.; Sugitate, T.; Suire, C.; Suleymanov, M.; Suljic, M.; Sultanov, R.; Šumbera, M.; Sumowidagdo, S.; Suzuki, K.; Swain, S.; Szabo, A.; Szarka, I.; Szczepankiewicz, A.; Szymanski, M.; Tabassam, U.; Takahashi, J.; Tambave, G. J.; Tanaka, N.; Tarhini, M.; Tariq, M.; Tarzila, M. G.; Tauro, A.; Tejeda Muñoz, G.; Telesca, A.; Terasaki, K.; Terrevoli, C.; Teyssier, B.; Thakur, D.; Thomas, D.; Tieulent, R.; Tikhonov, A.; Timmins, A. R.; Toia, A.; Tripathy, S.; Trogolo, S.; Trombetta, G.; Trubnikov, V.; Trzaska, W. H.; Tsuji, T.; Tumkin, A.; Turrisi, R.; Tveter, T. S.; Ullaland, K.; Umaka, E. N.; Uras, A.; Usai, G. L.; Utrobicic, A.; Vala, M.; Van Der Maarel, J.; Van Hoorne, J. W.; van Leeuwen, M.; Vanat, T.; Vande Vyvre, P.; Varga, D.; Vargas, A.; Vargyas, M.; Varma, R.; Vasileiou, M.; Vasiliev, A.; Vauthier, A.; Vázquez Doce, O.; Vechernin, V.; Veen, A. M.; Velure, A.; Vercellin, E.; Vergara Limón, S.; Vernet, R.; Vértesi, R.; Vickovic, L.; Vigolo, S.; Viinikainen, J.; Vilakazi, Z.; Villalobos Baillie, O.; Villatoro Tello, A.; Vinogradov, A.; Vinogradov, L.; Virgili, T.; Vislavicius, V.; Vodopyanov, A.; Völkl, M. A.; Voloshin, K.; Voloshin, S. A.; Volpe, G.; von Haller, B.; Vorobyev, I.; Voscek, D.; Vranic, D.; Vrláková, J.; Wagner, B.; Wagner, J.; Wang, H.; Wang, M.; Watanabe, D.; Watanabe, Y.; Weber, M.; Weber, S. G.; Weiser, D. F.; Wessels, J. P.; Westerhoff, U.; Whitehead, A. M.; Wiechula, J.; Wikne, J.; Wilk, G.; Wilkinson, J.; Willems, G. A.; Williams, M. C. S.; Windelband, B.; Winn, M.; Witt, W. E.; Yalcin, S.; Yang, P.; Yano, S.; Yin, Z.; Yokoyama, H.; Yoo, I.-K.; Yoon, J. H.; Yurchenko, V.; Zaccolo, V.; Zaman, A.; Zampolli, C.; Zanoli, H. J. C.; Zaporozhets, S.; Zardoshti, N.; Zarochentsev, A.; Závada, P.; Zaviyalov, N.; Zbroszczyk, H.; Zhalov, M.; Zhang, H.; Zhang, X.; Zhang, Y.; Zhang, C.; Zhang, Z.; Zhao, C.; Zhigareva, N.; Zhou, D.; Zhou, Y.; Zhou, Z.; Zhu, H.; Zhu, J.; Zichichi, A.; Zimmermann, A.; Zimmermann, M. B.; Zinovjev, G.; Zmeskal, J.

    2017-02-01

    Particle identification is an important feature of the ALICE detector at the LHC. In particular, for particle identification via the time-of-flight technique, the precise determination of the event collision time represents an important ingredient of the quality of the measurement. In this paper, the different methods used for such a measurement in ALICE by means of the T0 and the TOF detectors are reviewed. Efficiencies, resolution and the improvement of the particle identification separation power of the methods used are presented for the different LHC colliding systems (pp, p-Pb and Pb-Pb) during the first period of data taking of LHC (RUN 1).

  18. Post-processing of seismic parameter data based on valid seismic event determination

    DOEpatents

    McEvilly, Thomas V.

    1985-01-01

    An automated seismic processing system and method are disclosed, including an array of CMOS microprocessors for unattended battery-powered processing of a multi-station network. According to a characterizing feature of the invention, each channel of the network is independently operable to automatically detect, measure times and amplitudes, and compute and fit Fast Fourier transforms (FFT's) for both P- and S- waves on analog seismic data after it has been sampled at a given rate. The measured parameter data from each channel are then reviewed for event validity by a central controlling microprocessor and if determined by preset criteria to constitute a valid event, the parameter data are passed to an analysis computer for calculation of hypocenter location, running b-values, source parameters, event count, P- wave polarities, moment-tensor inversion, and Vp/Vs ratios. The in-field real-time analysis of data maximizes the efficiency of microearthquake surveys allowing flexibility in experimental procedures, with a minimum of traditional labor-intensive postprocessing. A unique consequence of the system is that none of the original data (i.e., the sensor analog output signals) are necessarily saved after computation, but rather, the numerical parameters generated by the automatic analysis are the sole output of the automated seismic processor.

  19. Dimension determination of precursive stall events in a single stage high speed compressor

    SciTech Connect

    Bright, M.M.; Qammar, H.K.; Hartley, T.T.

    1996-06-01

    This paper presents a study of the dynamics for a single-stage, axial-flow, high speed compressor core, specifically, the NASA Lewis rotor stage 37. Due to the overall blading design for this advanced core compressor, each stage has considerable tip loading and higher speed than most compressor designs, thus, the compressor operates closer to the stall margin. The onset of rotating stall is explained as bifurcations in the dynamics of axial compressors. Data taken from the compressor during a rotating stall event is analyzed. Through the use of a box-assisted correlation dimension methodology, the attractor dimension is determined during the bifurcations leading to rotating stall. The intent of this study is to examine the behavior of precursive stall events so as to predict the entrance into rotating stall. This information may provide a better means to identify, avoid or control the undersireable event of rotating stall formation in high speed compressor cores. {copyright} {ital 1996 American Institute of Physics.}

  20. Differences in the determinants of posttraumatic stress disorder and depression after a mass traumatic event

    PubMed Central

    Tracy, Melissa; Norris, Fran H.; Galea, Sandro

    2011-01-01

    Background Hurricane Ike struck the Galveston Bay area of Texas on September 13, 2008, leaving substantial destruction and a number of deaths in its wake. We assessed differences in the determinants of posttraumatic stress disorder (PTSD) and depression after this event, including the particular hurricane experiences, including post-event non-traumatic stressors, that were associated with these pathologies. Methods 658 adults who had been living in Galveston and Chambers counties, Texas in the month before Hurricane Ike were interviewed 2-5 months after the hurricane. We collected information on experiences during and after Hurricane Ike, PTSD and depressive symptoms in the month prior to the interview, and socio-demographic characteristics. Results The prevalence of past month hurricane-related PTSD and depression was 6.1% and 4.9%, respectively. Hurricane experiences, but not socio-demographic characteristics, were associated with Ike-related PTSD. By contrast, lower education and household income, and more lifetime stressors were associated with depression, as were hurricane exposures and hurricane-related stressors. When looking at specific hurricane-related stressors, loss or damage of sentimental possessions was associated with both PTSD and depression; however, health problems related to Ike were associated only with PTSD, whereas financial loss as a result of the hurricane was associated only with depression. Conclusions PTSD is indeed a disorder of event exposure, whereas risk of depression is more clearly driven by personal vulnerability and exposure to stressors. The role of non-traumatic stressors in shaping risk of both pathologies suggests that alleviating stressors after disasters has clear potential to mitigate the psychological sequelae of these events. PMID:21618672

  1. The Precise Determination of Cd Isotope Ratio in Geological Samples by MC-ICP-MS with Ion Exchange Separation

    NASA Astrophysics Data System (ADS)

    Du, C.; Hu, S.; Wang, D.; Jin, L.; Guo, W.

    2014-12-01

    Cadmium (Cd) is a trace element which occurs at μg g-1 level abundances in the crust. Cd isotopes have great prospects in the study of the cosmogony, the trace of anthropogenic sources, the micronutrient cycling and the ocean productivity. This study develops an optimized technique for the precise and accurate determination of Cd isotopic compositions. Cd was separated from the matrix by elution with AG-MP-1 anionic exchange chromatographic resin. The matrix elements (K, Na, Ca, Al, Fe, and Mg etc.), polyatomic interfered elements (Ge, Ga, Zr, Nb, Ru, and Mo), and isobaric interfered elements (In, Pd and most of Sn) were eluted using HCl with gradient descent concentrations (2, 0.3, 0.06, 0.012 and 0.0012 mol L-1). The same elution procedure was repeated to eliminate the residuel Sn (Sn/Cd < 0.018). The collected Cd was analyzed using MC-ICP-MS, in which the instrumental mass fractionation was controlled by a "sample-standard bracketing" technique. The recovery of Cd larger than 96.85%, and the δ114/110Cd are in the range of -1.43~+0.20‰ for ten geological reference materials (GSD-3a, GSD-5a, GSD-7a, GSD-6, GSD-9, GSD-10, GSD-11, GSD-12, GSD-23, and GSS-1). The δ114/110Cd obtained for GSS-1 soil sample relative to the NIST SRM 3108 Cd solution was 0.20, which was coherent with the literature values (0.08±0.23). This method had a precision of 0.001~0.002% (RSD), an error range of 0.06~0.14 (δ114/110Cd, 2σ), and a long-term reproducibility of 0.12 (δ114/110Cd, 2σ).

  2. Laboratory investigations of the effects of geologic heterogeneity on groundwater salinization and flush-out times from a tsunami-like event.

    PubMed

    Vithanage, M; Engesgaard, P; Jensen, K H; Illangasekare, T H; Obeysekera, J

    2012-08-01

    This intermediate scale laboratory experimental study was designed to improve the conceptual understanding of aquifer flushing time associated with diffuse saltwater contamination of coastal aquifers due to a tsunami-like event. The motivation comes from field observations made after the tsunami in December, 2004 in South Asia. The focus is on the role and effects of heterogeneity on flushing effectiveness. A scheme that combines experimentation in a 4.8m long laboratory tank and numerical modeling was used. To demonstrate the effects of geologic heterogeneity, plume migration and flushing times were analyzed in both homogeneous and layered media and under different boundary conditions (ambient flow, saltwater infiltration rate, freshwater recharge). Saltwater and freshwater infiltrations imitate the results of the groundwater salinization from the tsunami and freshening from the monsoon rainfall. The saltwater plume behavior was monitored both through visual observations (digital photography) of the dyed salt water and using measurements taken from several electrical conductivity sensors installed through the tank walls. The variable-density, three dimensional code HST3D was used to simulate the tank experiments and understand the fate and movement of the saltwater plume under field conditions. The results from the tank experiments and modeling demonstrated that macro-scale heterogeneity significantly influenced the migration patterns and flushing times of diffuse saltwater contamination. Ambient flow had a direct influence on total flush-out time, and heterogeneity impacted flush-out times for the top part of the tank and total flush-out times. The presence of a continuous low-permeability layer caused a 40% increase in complete flush-out time due to the slower flow of salt water in the low-permeability layer. When a relatively small opening was introduced in the low-permeability layer, salt water migrated quickly into a higher-permeable layer below causing a

  3. Determination of gold and silver in geological samples by focused infrared digestion: A re-investigation of aqua regia digestion.

    PubMed

    Wang, Yong; Baker, Laura A; Brindle, Ian D

    2016-02-01

    Focused infrared radiation-based digestions, for the determination of gold and silver, can be achieved in a timeframe as short as 10-15 min, making it an attractive candidate technology for the mining industry, where very large numbers of samples are analyzed on a daily basis. An investigation was carried out into gold and silver dissolution chemistry from geological samples using this novel digestion technique. This study investigated in-depth the issue of low recoveries of gold from aqua regia (AR) digestions, reported by a number of researchers. Conventional AR digestions consistently delivered gold recoveries in a range of 69-80% of the certified values for the four certified reference materials (CRM) employed (CCU-1d, SN26, OREAS 62c, and AMiS 0274), while silver recoveries were satisfactory. By gradually shifting the HCl:HNO3 ratio (v/v) from 3:1 to a reversed 1:3 ratio, recoveries of gold and silver exhibited inverse trends. At a HCl:HNO3 ratio of 1:3, complete recovery of gold was achieved with excellent reproducibility in all CRMs. Meanwhile, silver recoveries plunged significantly at this ratio in samples with higher silver concentrations. Silver values were recovered, however, when the silver was re-solubilized by adding a small volume of concentrated HCl to the cooled reverse aqua regia digests. Recoveries of base metals, such as Fe and Cu, were satisfactory throughout and were much less sensitive to changes in the digestion medium. Using four CRMs and five real-world gold/silver containing samples, the utility of the proposed reverse aqua regia was systematically studied. The uncomplicated nature of the digestion methods reported here, that are fast, effective and inexpensive, may be useful to analysts developing/optimizing their methods for the rapid determination of Au and Ag in a variety of mineral phases, particularly where rapid results are desirable, such as in prospecting and mine development. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. Determination of tungsten in niobium-tantalum, vanadium and molybdenum bearing geological samples using derivative spectrophotometry and ICP-AES.

    PubMed

    Padmasubashini, V; Ganguly, M K; Satyanarayana, K; Malhotra, R K

    1999-10-01

    Two different procedures, one using derivative spectrophotometry and another using inductively coupled plasma atomic emission spectrometry (ICP-AES) have been developed for the determination of tungsten in niobate-tantalates, tin slag samples, ores, concentrates and vanadium and molybdenum bearing geological materials. In the first method involving derivative spectrophotometry, 0.05-0.5 g of the sample is fused with sodium hydroxide, the tungsten is extracted by leaching the melt with distilled water and estimated as thiocyanate using a second derivative spectrophotometric method in the presence of interferents, i.e. Nb, Mo and V, without separating them. Mixtures of tungsten with V, Nb and Mo are used for standardizing the various parameters like zero-crossing wavelength, wavelength range, etc. Tolerance limits for V, Nb and Mo have also been evaluated. In the second method involving ICP-AES, 0.05-0.5 g of sample is fused with KHSO(4) to a clear melt and dissolved in ammonium oxalate solution. Ammonium hydroxide precipitation is then carried out to separate Nb and Ta as hydroxides and the filtrate is boiled with nitric acid to destroy the oxalates before aspiration into the plasma for measurement of tungsten values by ICP-AES using the 207.911 nm emission line. Both methods have been applied to niobate-tantalate and tin slag samples and the results obtained are reported in this paper. The values obtained by both methods are in good agreement with each other. The proposed methods have also been applied to the determination of tungsten in two Canadian Certified Reference Standards (CT-1 and MP-2) and the values obtained are in good agreement with the certified values and the R.S.D.% in case of the ICP-AES method varied from 1-2% at >1000 mug g(-1) level to 9.4% at the 20 mug g(-1) level whereas the R.S.D.% in case of the derivative method varied from 1 to 7.8%.

  5. Orbit Determination and Navigation of the Time History of Events and Macroscale Interactions during Substorms (THEMIS)

    NASA Technical Reports Server (NTRS)

    Morinelli, Patrick; Cosgrove, jennifer; Blizzard, Mike; Nicholson, Ann; Robertson, Mika

    2007-01-01

    This paper provides an overview of the launch and early orbit activities performed by the NASA Goddard Space Flight Center's (GSFC) Flight Dynamics Facility (FDF) in support of five probes comprising the Time History of Events and Macroscale Interactions during Substorms (THEMIS) spacecraft. The FDF was tasked to support THEMIS in a limited capacity providing backup orbit determination support for validation purposes for all five THEMIS probes during launch plus 30 days in coordination with University of California Berkeley Flight Dynamics Center (UCB/FDC). The FDF's orbit determination responsibilities were originally planned to be as a backup to the UCB/FDC for validation purposes only. However, various challenges early on in the mission and a Spacecraft Emergency declared thirty hours after launch placed the FDF team in the role of providing the orbit solutions that enabled contact with each of the probes and the eventual termination of the Spacecraft Emergency. This paper details the challenges and various techniques used by the GSFC FDF team to successfully perform orbit determination for all five THEMIS probes during the early mission. In addition, actual THEMIS orbit determination results are presented spanning the launch and early orbit mission phase. Lastly, this paper enumerates lessons learned from the THEMIS mission, as well as demonstrates the broad range of resources and capabilities within the FDF for supporting critical launch and early orbit navigation activities, especially challenging for constellation missions.

  6. Orbit Determination and Navigation of the Time History of Events and Macroscale Interactions during Substorms (THEMIS)

    NASA Technical Reports Server (NTRS)

    Morinelli, Patrick; Cosgrove, Jennifer; Blizzard, Mike; Robertson, Mike

    2007-01-01

    This paper provides an overview of the launch and early orbit activities performed by the NASA Goddard Space Flight Center's (GSFC) Flight Dynamics Facility (FDF) in support of five probes comprising the Time History of Events and Macroscale Interactions during Substorms (THEMIS) spacecraft. The FDF was tasked to support THEMIS in a limited capacity providing backup orbit determination support for validation purposes for all five THEMIS probes during launch plus 30 days in coordination with University of California Berkeley Flight Dynamics Center (UCB/FDC)2. The FDF's orbit determination responsibilities were originally planned to be as a backup to the UCB/FDC for validation purposes only. However, various challenges early on in the mission and a Spacecraft Emergency declared thirty hours after launch placed the FDF team in the role of providing the orbit solutions that enabled contact with each of the probes and the eventual termination of the Spacecraft Emergency. This paper details the challenges and various techniques used by the GSFC FDF team to successfully perform orbit determination for all five THEMIS probes during the early mission. In addition, actual THEMIS orbit determination results are presented spanning the launch and early orbit mission phase. Lastly, this paper enumerates lessons learned from the THEMIS mission, as well as demonstrates the broad range of resources and capabilities within the FDF for supporting critical launch and early orbit navigation activities, especially challenging for constellation missions.

  7. 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)

  8. 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)

  9. Engineering Geology.

    ERIC Educational Resources Information Center

    Ivey, John B.

    1983-01-01

    Engineering geology activities in government and the private sector are highlighted. Also highlighted are conferences in this field, awards presented at conferences (including an award to an undergraduate geology student), and a new publication "Geotechnology in Massachusetts." (JN)

  10. 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)

  11. Mathematical Geology.

    ERIC Educational Resources Information Center

    Jones, Thomas A.

    1983-01-01

    Mathematical techniques used to solve geological problems are briefly discussed (including comments on use of geostatistics). Highlights of conferences/meetings and conference papers in mathematical geology are also provided. (JN)

  12. Differences in the determinants of posttraumatic stress disorder and depression after a mass traumatic event.

    PubMed

    Tracy, Melissa; Norris, Fran H; Galea, Sandro

    2011-08-01

    Hurricane Ike struck the Galveston Bay area of Texas on September 13, 2008, leaving substantial destruction and a number of deaths in its wake. We assessed differences in the determinants of posttraumatic stress disorder (PTSD) and depression after this event, including the particular hurricane experiences, including postevent nontraumatic stressors, that were associated with these pathologies. 658 adults who had been living in Galveston and Chambers counties, TX in the month before Hurricane Ike were interviewed 2-5 months after the hurricane. We collected information on experiences during and after Hurricane Ike, PTSD and depressive symptoms in the month before the interview, and socio-demographic characteristics. The prevalence of past month hurricane-related PTSD and depression was 6.1 and 4.9%, respectively. Hurricane experiences, but not socio-demographic characteristics, were associated with Ike-related PTSD. By contrast, lower education and household income, and more lifetime stressors were associated with depression, as were hurricane exposures and hurricane-related stressors. When looking at specific hurricane-related stressors, loss or damage of sentimental possessions was associated with both PTSD and depression; however, health problems related to Ike were associated only with PTSD, whereas financial loss as a result of the hurricane was associated only with depression. PTSD is indeed a disorder of event exposure, whereas risk of depression is more clearly driven by personal vulnerability and exposure to stressors. The role of nontraumatic stressors in shaping risk of both pathologies suggests that alleviating stressors after disasters has clear potential to mitigate the psychological sequelae of these events. © 2011 Wiley-Liss, Inc.

  13. DETERMINING THE PHYSICAL LENS PARAMETERS OF THE BINARY GRAVITATIONAL MICROLENSING EVENT MOA-2009-BLG-016

    SciTech Connect

    Hwang, K.-H.; Han, C.; Bond, I. A.; Lin, W.; Ling, C. H.; Miyake, N.; Abe, F.; Fukui, A.; Furusawa, K.; Hayashi, F.; Hosaka, S.; Itow, Y.; Kamiya, K.; Makita, S.; Masuda, K.; Bennett, D. P.; Botzler, C. S.; Hearnshaw, J. B.; Kilmartin, P. M.; Korpela, A.

    2010-07-01

    We report the result of the analysis of the light curve of the microlensing event MOA-2009-BLG-016. The light curve is characterized by a short-duration anomaly near the peak and an overall asymmetry. We find that the peak anomaly is due to a binary companion to the primary lens and the asymmetry of the light curve is explained by the parallax effect caused by the acceleration of the observer over the course of the event due to the orbital motion of the Earth around the Sun. In addition, we detect evidence for the effect of the finite size of the source near the peak of the event, which allows us to measure the angular Einstein radius of the lens system. The Einstein radius combined with the microlens parallax allows us to determine the total mass of the lens and the distance to the lens. We identify three distinct classes of degenerate solutions for the binary lens parameters, where two are manifestations of the previously identified degeneracies of close/wide binaries and positive/negative impact parameters, while the third class is caused by the symmetric cycloid shape of the caustic. We find that, for the best-fit solution, the estimated mass of the lower-mass component of the binary is (0.04 {+-} 0.01) M{sub sun}, implying a brown-dwarf companion. However, there exists a solution that is worse only by {Delta}{chi}{sup 2} {approx} 3 for which the mass of the secondary is above the hydrogen-burning limit. Unfortunately, resolving these two degenerate solutions will be difficult as the relative lens-source proper motions for both are similar and small ({approx}1 mas yr{sup -1}) and thus the lens will remain blended with the source for the next several decades.

  14. Direct determination of platinum group elements and their distributions in geological and environmental samples at the ng g(-1) level using LA-ICP-IDMS.

    PubMed

    Boulyga, Sergei F; Heumann, Klaus G

    2005-10-01

    Laser ablation inductively coupled plasma isotope dilution mass spectrometry (LA-ICP-IDMS) was applied to the direct and simultaneous determination of the platinum group elements (PGEs) Pt, Pd, Ru, and Ir in geological and environmental samples. A special laser ablation system with high ablation rates was used, along with sector field ICP-MS. Special attention was paid to deriving the distributions of PGEs in the pulverized samples. IDMS could not be applied to the (mono-isotopic) Rh, but the similar ablation behavior of Ru and Rh allowed Rh to be simultaneously determined via relative sensitivity coefficients. The laser ablation process produces hardly any oxide ions (which usually cause interference in PGE analysis with liquid sample injection), so the ICP-MS can be run in its low mass resolution but high-sensitivity mode. The detection limits obtained for the geological samples were 0.16 ng g(-1), 0.14 ng g(-1), 0.08 ng g(-1), 0.01 ng g(-1) and 0.06 ng g(-1) for Ru, Rh, Pd, Ir and Pt, respectively. LA-ICP-IDMS was applied to different geological reference materials (TDB-1, WGB-1, UMT-1, WMG-1, SARM-7) and the road dust reference material BCR-723, which are only certified for some of the PGEs. Comparisons with certified values as well as with indicative values from the literature demonstrated the validity of the LA-ICP-IDMS method. The PGE concentrations in subsamples of the road dust reference material correspond to a normal distribution, whereas the distributions in the geological reference materials TDB-1, WGB-1, UMT-1, WMG-1, and SARM-7 are more complex. For example, in the case of Ru, a logarithmic normal distribution best fits the analyzed concentrations in TDB-1 subsamples, whereas a pronounced nugget effect was found for Pt in most geological samples.

  15. Geologic nozzles

    USGS Publications Warehouse

    Werner, Kieffer S.

    1989-01-01

    The importance of the low characteristic velocities of geologic fluids has not been widely recognized, and as a result, the importance of supercritical and supersonic flow in geological processes has generally been underestimated. The lateral blast at Mount St. Helens, Washington, propelled a gas heavily laden with dust into the atmosphere. Because of the low sound speed in this gas (about 100 m/s), the flow was internally supersonic. Old Faithful Geyser, Wyoming, is a converging-diverging nozzle in which liquid water refilling the conduit during the recharge cycle changes during eruption into a two-phase liquid-vapor mixture with a very low sound velocity. The high sound speed of liquid water determines the characteristics of harmonic tremor observed at the geyser during the recharge interval, whereas the low sound speed of the liquid-vapor mixture influences the fluid flow characteristics of the eruption. At the rapids of the Colorado River in the Grand Canyon, Arizona, the channel is constricted into the shape of a converging-diverging nozzle by the debris flows that enter from tributary canyons. Both subcritical and supercritical flow occur within the rapids. -from Author

  16. Joint probabilistic determination of earthquake location and velocity structure: application to local and regional events

    NASA Astrophysics Data System (ADS)

    Beucler, E.; Haugmard, M.; Mocquet, A.

    2016-12-01

    The most widely used inversion schemes to locate earthquakes are based on iterative linearized least-squares algorithms and using an a priori knowledge of the propagation medium. When a small amount of observations is available for moderate events for instance, these methods may lead to large trade-offs between outputs and both the velocity model and the initial set of hypocentral parameters. We present a joint structure-source determination approach using Bayesian inferences. Monte-Carlo continuous samplings, using Markov chains, generate models within a broad range of parameters, distributed according to the unknown posterior distributions. The non-linear exploration of both the seismic structure (velocity and thickness) and the source parameters relies on a fast forward problem using 1-D travel time computations. The a posteriori covariances between parameters (hypocentre depth, origin time and seismic structure among others) are computed and explicitly documented. This method manages to decrease the influence of the surrounding seismic network geometry (sparse and/or azimuthally inhomogeneous) and a too constrained velocity structure by inferring realistic distributions on hypocentral parameters. Our algorithm is successfully used to accurately locate events of the Armorican Massif (western France), which is characterized by moderate and apparently diffuse local seismicity.

  17. Health priorities and perceived health determinants among South Australians attending GLBTI festival events.

    PubMed

    Rogers, Gary

    2007-04-01

    Health differentials related to the social position of people whose sexual attraction or gender identity differs from that of the majority may be the 'forgotten inequity' in contemporary Australian discourses on health inequalities and social inclusion. What sexually- and gender-diverse communities see as health priorities and the social determinants of their health have been little studied in Australia. This survey explored the experience and opinions of a convenience sample of gay, lesbian, bisexual, trangender and intersex (GLBTI) people in South Australia. A pencil and paper survey was administered to people attending events associated with the Feast GLBTI festival in Adelaide in 2004 and good participation rates were obtained. Two hundred and fifty-three people completed the survey, of which 122 identified as female, 124 as male and seven as other genders. Depression, HIV, suicide, family relationship problems and alcohol problems were seen as the most important health issues for these communities, while discrimination under the law and in daily life were rated the most important health determinants. GLBTI South Australians surveyed identified priority health issues for their communities and identified legal and personal discrimination as significant determinants of their health.

  18. Using geologic conditions and multiattribute decision analysis to determine the relative favorability of selected areas for siting a high-level radioactive waste repository

    SciTech Connect

    Harrison, W.; Edgar, D.E.; Baker, C.H.; Buehring, W.A.; Whitfield, R.G.; Van Luik, A.E.J.; Sood, M.K.; Flower, M.F.J.; Warren, M.F.; Jusko, M.J.; Peerenboom, J.P.; Bogner, J.E.

    1988-05-01

    A method is presented for determining the relative favorability of geologically complex areas for isolating high-level radioactive wastes. In applying the method to the northeastern region of the United States, seismicity and tectonic activity were the screening criteria used to divide the region into three areas of increasing seismotectonic risk. Criteria were then used to subdivide the area of lowest seismotectonic risk into six geologically distinct subareas including characteristics, surface-water and groundwater hydrology, potential human intrusion, site geometry, surface characteristics, and tectonic environment. Decision analysis was then used to identify the subareas most favorable from a geologic standpoint for further investigation, with a view to selecting a site for a repository. Three subareas (parts of northeastern Vermont, northern New Hampshire, and western Maine) were found to be the most favorable, using this method and existing data. However, because this study assessed relative geologic favorability, no conclusions should be drawn concerning the absolute suitability of individual subareas for high-level radioactive waste isolation. 34 refs., 7 figs., 20 tabs.

  19. The determination of observed atmospheric differences between heavy and light precipitation events in New Jersey, USA

    NASA Astrophysics Data System (ADS)

    Harnack, Robert; Apffel, Kirk; Georgescu, Matei; Baines, Shaun

    2001-10-01

    The climatology of a limited sample of heavy precipitation events occurring in New Jersey, USA, is studied via statistical averaging and frequency histograms of environmental conditions at the event location. Also, the spatial distribution of related circulation features is examined. In addition, statistical differences between conditions accompanying the heavy (HEAVY) and a selected sample of light (LIGHT) precipitation events is determined. A large number of surface, standard level, stability and wind shear variables are employed as well as synoptic-scale circulation features. Variables that are identified as statistically significant, after a Student's t-test is applied to a sample mean and standard deviation are listed by season. In addition, scatter plot and composite maps are produced to illustrate conditions concurrent with the onset of heavy precipitation.In general, there are only slight differences between values obtained for the HEAVY sample and the LIGHT sample. However, the differences are large enough for some variables in some seasons that the forecaster may be able to use these results to advantage. In particular: (i) a significantly warmer and moister atmosphere at selected levels is indicated for the HEAVY sample for Autumn and Winter but not for Spring and Summer; (ii) upper-tropospheric divergence is significantly greater in all seasons except Summer; and (iii) wind shear is significantly larger in all seasons except Summer.There is much similarity in the mean position of examined synoptic features such as troughs, vorticity maxima, jet axes and jet streaks for the two samples. However, the amplitude of circulation in the troposphere is much larger for the HEAVY sample, especially in the lower troposphere. In addition, the 850-hPa wind maximum axis (low-level jet indication) is much more often oriented from south to north and located within 300 km of the event location for the HEAVY cases. There was surprisingly no significant sample difference

  20. Determination of the number of J/ψ events with inclusive J/ψ decays

    NASA Astrophysics Data System (ADS)

    Ablikim, M.; Achasov, M. N.; Ai, X. C.; Albayrak, O.; Albrecht, M.; Ambrose, D. J.; Amoroso, A.; An, F. F.; An, Q.; Bai, J. Z.; Baldini Ferroli, R.; Ban, Y.; Bennett, D. W.; Bennett, J. V.; Bertani, M.; Bettoni, D.; Bian, J. M.; Bianchi, F.; Boger, E.; Boyko, I.; Briere, R. A.; Cai, H.; Cai, X.; Cakir, O.; Calcaterra, A.; Cao, G. F.; Cetin, S. A.; Chang, J. F.; Chelkov, G.; Chen, G.; Chen, H. S.; Chen, H. Y.; Chen, J. C.; Chen, M. L.; Chen, S. J.; Chen, X.; Chen, X. R.; Chen, Y. B.; Cheng, H. P.; Chu, X. K.; Cibinetto, G.; Dai, H. L.; Dai, J. P.; Dbeyssi, A.; Dedovich, D.; Deng, Z. Y.; Denig, A.; Denysenko, I.; Destefanis, M.; De Mori, F.; Ding, Y.; Dong, C.; Dong, J.; Dong, L. Y.; Dong, M. Y.; Dou, Z. L.; Du, S. X.; Duan, P. F.; Fan, J. Z.; Fang, J.; Fang, S. S.; Fang, X.; Fang, Y.; Farinelli, R.; Fava, L.; Fedorov, O.; Feldbauer, F.; Felici, G.; Feng, C. Q.; Fioravanti, E.; Fritsch, M.; Fu, C. D.; Gao, Q.; Gao, X. L.; Gao, X. Y.; Gao, Y.; Gao, Z.; Garzia, I.; Goetzen, K.; Gong, L.; Gong, W. X.; Gradl, W.; Greco, M.; Gu, M. H.; Gu, Y. T.; Guan, Y. H.; Guo, A. Q.; Guo, L. B.; Guo, Y.; Guo, Y. P.; Haddadi, Z.; Hafner, A.; Han, S.; Hao, X. Q.; Harris, F. A.; He, K. L.; Held, T.; Heng, Y. K.; Hou, Z. L.; Hu, C.; Hu, H. M.; Hu, J. F.; Hu, T.; Hu, Y.; Huang, G. S.; Huang, J. S.; Huang, X. T.; Huang, Y.; Hussain, T.; Ji, Q.; Ji, Q. P.; Ji, X. B.; Ji, X. L.; Jiang, L. W.; Jiang, X. S.; Jiang, X. Y.; Jiao, J. B.; Jiao, Z.; Jin, D. P.; Jin, S.; Johansson, T.; Julin, A.; Kalantar-Nayestanaki, N.; Kang, X. L.; Kang, X. S.; Kavatsyuk, M.; Ke, B. C.; Kiese, P.; Kliemt, R.; Kloss, B.; Kolcu, O. B.; Kopf, B.; Kornicer, M.; Kupsc, A.; Kühn, W.; Lange, J. S.; Lara, M.; Larin, P.; Leng, C.; Li, C.; Li, Cheng; Li, D. M.; Li, F.; Li, F. Y.; Li, G.; Li, H. B.; Li, J. C.; Li, Jin; Li, K.; Li, K.; Li, Lei; Li, P. R.; Li, Q. Y.; Li, T.; Li, W. D.; Li, W. G.; Li, X. L.; Li, X. N.; Li, X. Q.; Li, Z. B.; Liang, H.; Liang, Y. F.; Liang, Y. T.; Liao, G. R.; Lin, D. X.; Liu, B. J.; Liu, C. X.; Liu, D.; Liu, F. H.; Liu, Fang; Liu, Feng; Liu, H. B.; Liu, H. H.; Liu, H. H.; Liu, H. M.; Liu, J.; Liu, J. B.; Liu, J. P.; Liu, J. Y.; Liu, K.; Liu, K. Y.; Liu, L. D.; Liu, P. L.; Liu, Q.; Liu, S. B.; Liu, X.; Liu, Y. B.; Liu, Z. A.; Liu, Zhiqing; Loehner, H.; Lou, X. C.; Lu, H. J.; Lu, J. G.; Lu, Y.; Lu, Y. P.; Luo, C. L.; Luo, M. X.; Luo, T.; Luo, X. L.; Lyu, X. R.; Ma, F. C.; Ma, H. L.; Ma, L. L.; Ma, Q. M.; Ma, T.; Ma, X. N.; Ma, X. Y.; Ma, Y. M.; Maas, F. E.; Maggiora, M.; Mao, Y. J.; Mao, Z. P.; Marcello, S.; Messchendorp, J. G.; Min, J.; Min, T. J.; Mitchell, R. E.; Mo, X. H.; Mo, Y. J.; Morales Morales, C.; Muchnoi, N. Yu.; Muramatsu, H.; Nefedov, Y.; Nerling, F.; Nikolaev, I. B.; Ning, Z.; Nisar, S.; Niu, S. L.; Niu, X. Y.; Olsen, S. L.; Ouyang, Q.; Pacetti, S.; Pan, Y.; Patteri, P.; Pelizaeus, M.; Peng, H. P.; Peters, K.; Pettersson, J.; Ping, J. L.; Ping, R. G.; Poling, R.; Prasad, V.; Qi, H. R.; Qi, M.; Qian, S.; Qiao, C. F.; Qin, L. Q.; Qin, N.; Qin, X. S.; Qin, Z. H.; Qiu, J. F.; Rashid, K. H.; Redmer, C. F.; Ripka, M.; Rong, G.; Rosner, Ch.; Ruan, X. D.; Santoro, V.; Sarantsev, A.; Savrié, M.; Schoenning, K.; Schumann, S.; Shan, W.; Shao, M.; Shen, C. P.; Shen, P. X.; Shen, X. Y.; Sheng, H. Y.; Song, W. M.; Song, X. Y.; Sosio, S.; Spataro, S.; Sun, G. X.; Sun, J. F.; Sun, S. S.; Sun, Y. J.; Sun, Y. Z.; Sun, Z. J.; Sun, Z. T.; Tang, C. J.; Tang, X.; Tapan, I.; Thorndike, E. H.; Tiemens, M.; Ullrich, M.; Uman, I.; Varner, G. S.; Wang, B.; Wang, B. L.; Wang, D.; Wang, D. Y.; Wang, K.; Wang, L. L.; Wang, L. S.; Wang, M.; Wang, P.; Wang, P. L.; Wang, W.; Wang, W. P.; Wang, X. F.; Wang, Y. D.; Wang, Y. F.; Wang, Y. Q.; Wang, Z.; Wang, Z. G.; Wang, Z. H.; Wang, Z. Y.; Weber, T.; Wei, D. H.; Weidenkaff, P.; Wen, S. P.; Wiedner, U.; Wolke, M.; Wu, L. H.; Wu, Z.; Xia, L.; Xia, L. G.; Xia, Y.; Xiao, D.; Xiao, H.; Xiao, Z. J.; Xie, Y. G.; Xiu, Q. L.; Xu, G. F.; Xu, L.; Xu, Q. J.; Xu, Q. N.; Xu, X. P.; Yan, L.; Yan, W. B.; Yan, W. C.; Yan, Y. H.; Yang, H. J.; Yang, H. X.; Yang, L.; Yang, Y. X.; Ye, M.; Ye, M. H.; Yin, J. H.; Yu, B. X.; Yu, C. X.; Yu, J. S.; Yuan, C. Z.; Yuan, W. L.; Yuan, Y.; Yuncu, A.; Zafar, A. A.; Zallo, A.; Zeng, Y.; Zeng, Z.; Zhang, B. X.; Zhang, B. Y.; Zhang, C.; Zhang, C. C.; Zhang, D. H.; Zhang, H. H.; Zhang, H. Y.; Zhang, J. J.; Zhang, J. L.; Zhang, J. Q.; Zhang, J. W.; Zhang, J. Y.; Zhang, J. Z.; Zhang, K.; Zhang, L.; Zhang, X. Y.; Zhang, Y.; Zhang, Y. H.; Zhang, Y. N.; Zhang, Y. T.; Zhang, Yu; Zhang, Z. H.; Zhang, Z. P.; Zhang, Z. Y.; Zhao, G.; Zhao, J. W.; Zhao, J. Y.; Zhao, J. Z.; Zhao, Lei; Zhao, Ling; Zhao, M. G.; Zhao, Q.; Zhao, Q. W.; Zhao, S. J.; Zhao, T. C.; Zhao, Y. B.; Zhao, Z. G.; Zhemchugov, A.; Zheng, B.; Zheng, J. P.; Zheng, W. J.; Zheng, Y. H.; Zhong, B.; Zhou, L.; Zhou, X.; Zhou, X. K.; Zhou, X. R.; Zhou, X. Y.; Zhu, K.; Zhu, K. J.; Zhu, S.; Zhu, S. H.; Zhu, X. L.; Zhu, Y. C.; Zhu, Y. S.; Zhu, Z. A.; Zhuang, J.; Zotti, L.; Zou, B. S.; Zou, J. H.; BESIII Collaboration

    2017-01-01

    A measurement of the number of J/ψ events collected with the BESIII detector in 2009 and 2012 is performed using inclusive decays of the J/ψ. The number of J/ψ events taken in 2009 is recalculated to be (223.7 ± 1.4) × 106, which is in good agreement with the previous measurement, but with significantly improved precision due to improvements in the BESIII software. The number of J/ψ events taken in 2012 is determined to be (1086.9 ± 6.0) × 106. In total, the number of J/ψ events collected with the BESIII detector is measured to be (1310.6 ± 7.0) × 106, where the uncertainty is dominated by systematic effects and the statistical uncertainty is negligible. Supported by National Key Basic Research Program of China (2015CB856700), National Natural Science Foundation of China (NSFC) (10805053, 11125525, 11175188, 11235011, 11322544, 11335008, 11425524), Chinese Academy of Sciences (CAS) Large-Scale Scientific Facility Program, the CAS Center for Excellence in Particle Physics (CCEPP), Collaborative Innovation Center for Particles and Interactions (CICPI), Joint Large-Scale Scientific Facility Funds of NSFC and CAS (11179007, U1232201, U1232107, U1332201), CAS (KJCX2-YW-N29, KJCX2-YW-N45), 100 Talents Program of CAS, INPAC and Shanghai Key Laboratory for Particle Physics and Cosmology, German Research Foundation DFG (Collaborative Research Center CRC-1044), Istituto Nazionale di Fisica Nucleare, Italy; Ministry of Development of Turkey (DPT2006K-120470), Russian Foundation for Basic Research (14-07-91152), U. S. Department of Energy (DE-FG02-04ER41291, DE-FG02-05ER41374, DE-FG02-94ER40823, DESC0010118), U.S. National Science Foundation, University of Groningen (RuG) and the Helmholtzzentrum fuer Schwerionenforschung GmbH (GSI), Darmstadt; WCU Program of National Research Foundation of Korea (R32-2008-000-10155-0)

  1. A tool to determine financial impact of adverse events in health care: healthcare quality calculator.

    PubMed

    Yarbrough, Wendell G; Sewell, Andrew; Tickle, Erin; Rhinehardt, Eric; Harkleroad, Rod; Bennett, Marc; Johnson, Deborah; Wen, Li; Pfeiffer, Matthew; Benegas, Manny; Morath, Julie

    2014-12-01

    Hospital leaders lack tools to determine the financial impact of poor patient outcomes and adverse events. To provide health-care leaders with decision support for investments to improve care, we created a tool, the Healthcare Quality Calculator (HQCal), which uses institution-specific financial data to calculate impact of poor patient outcomes or quality improvement on present and future margin. Excel and Web-based versions of the HQCal were based on a cohort study framework and created with modular components including major drivers of cost and reimbursement. The Healthcare Quality Calculator (HQCal) compares payment, cost, and profit/loss for patients with and without poor outcomes or quality issues. Cost and payment information for groups with and without quality issues are used by the HQCal to calculate profit or loss. Importantly, institution-specific payment and cost data are used to calculate financial impact and attributable cost associated with poor patient outcomes, adverse events, or quality issues. Because future cost and reimbursement changes can be forecast, the HQCal incorporates a forward-looking component. The flexibility of the HQCal was demonstrated using surgical site infections after abdominal surgery and postoperative surgical airway complications. The Healthcare Quality Calculator determines financial impact of poor patient outcomes and the benefit of initiatives to improve quality. The calculator can identify quality issues that would provide the largest financial benefit if improved; however, it cannot identify specific interventions. The calculator provides a tool to improve transparency regarding both short- and long-term financial consequences of funding, or failing to fund, initiatives to close gaps in quality or improve patient outcomes.

  2. 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

    Akın, Çiğdem; 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

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

    PubMed

    Akın, Ciğdem; 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

  4. Experimental determination of trace element mobility in UK North Sea sandstones under conditions of geological CO2 storage

    NASA Astrophysics Data System (ADS)

    Carruthers, Kit; Wilkinson, Mark; Butler, Ian B.

    2016-04-01

    Offshore UK geological formations have the capacity to store > 100 years' worth of UK CO2 output from industry and power generation, if utilised for carbon capture and storage (CCS) schemes. During CO2 storage or CO2-Enhanced Oil Recovery (CO2-EOR), formation waters may be produced at the surface to be disposed of into the marine environment. Laboratory and field scale studies, with an emphasis on the effects on onshore shallow potable groundwaters, have shown that CO2 dissolution in formation waters during injection and storage acidifies the waters and promotes mobilisation from the reservoir sandstones of major and trace elements into solution. Of relevance to the UK context, eight of these elements are specifically identified as potentially hazardous to the marine environment: As, Cd, Cr, Cu, Hg, Ni, Pb, Zn. Batch experiments using simple borosilicate flasks sat on heating mantles were used in this study to determine concentrations of these 8 elements which could be leached from selected North Sea sandstones with bubbled CO2 and saline solutions, at formation temperatures. These concentration data were compared with produced water data from current UK offshore hydrocarbon extraction activities. The comparison showed that, taking the North Sea as a whole, the experimental results fall within the range of concentrations of current oil and gas activities. However, on a field-by-field basis, concentrations may be enhanced with CO2 storage, such that they are higher than waters normally produced from a particular field. Lead, nickel and zinc showed the greatest concentration increases in the experiments with the addition of CO2, with the other five elements of interest not showing any strong trends with respect to enhanced CO2. The origin of the increased trace element concentrations was investigated using sequential leaching experiments. A six step method of increasingly aggressive leaching was developed, based on modification of methods outlined by Tessier et al

  5. Determining the Return Period of Storm Surge Events in the Philippines

    NASA Astrophysics Data System (ADS)

    Santiago, Joy; Suarez, John Kenneth; Lapidez, John Phillip; Mendoza, Jerico; Caro, Carl Vincent; Tablazon, Judd; Ladiero, Christine; Mahar Francisco Lagmay, Alfredo

    2015-04-01

    The devastating damages generated by the Tropical Cyclone Haiyan storm surges in Eastern Samar, Philippines prompted the Department of Science and Technology-Project NOAH (Nationwide Operational Assessment of Hazards) to calculate the return period and storm surge exceedance probability of these events. The recurrence interval or the period of return of a storm surge event is the estimated likelihood that that event would occur again. Return periods are measured through historical data denoting the interval of recurrence in average over a period of time. The exceedance probability however, is a graphical representation that describes the probability that some various levels of loss will be exceeded over a future time period or will be surpassed over a given time. DOST-Project NOAH simulates storm surge height time series using JMA storm surge model which is a numerical model based on shallow water equations. To determine the period of recurrence of storm surges with this type of intensity, the agency intends to compute the estimation of storm surge heights generated by tropical cyclones for 2-year, 5-year, 10-year, 25-year, 50-year and 100-year return periods for the Philippine coast. The storm surge time series generated from JMA combined with WXTide simulation, a software containing archives/catalogues of world-wide astronomical tides, and 5-meter resolution DEM were used as input parameters for the inundation model, which shows probable extent of flooding at a specific storm surge return period. Flo-2D two-dimensional flood routing model, a GIS integrated software tool that facilitates the creation of the flood model grid system, was used for flood hazard model. It is a simple volume conservation model composed of processor program that facilitate graphical editing and mapping of flooding details which uses continuity equation and the dynamic wave momentum equations. The measurements of storm surge return period and probable extent of coastal flooding in the

  6. Determination of maximal lactate steady state response in selected sports events.

    PubMed

    Beneke, R; von Duvillard, S P

    1996-02-01

    Maximal lactate steady state (MLSS) refers to the upper limit of blood lactate concentration indicating an equilibrium between lactate production and lactate elimination during constant workload. The aim of the present study was to investigate whether different levels of MLSS may explain different blood lactate concentration (BLC) levels at submaximal workload in the sports events of rowing, cycling, and speed skating. Eleven rowers (mean +/- SD, age 20.1 +/- 1.5 yr, height 188.7 +/- 6.2 cm, weight 82.7 +/- 8.0 kg), 16 cyclists and triathletes (age 23.6 +/- 3.0 yr, height 181.4 +/- 5.6 cm, weight 72.5 +/- 6.2 kg), and 6 speed skaters (age 23.3 +/- 6.6 yr, height 179.5 +/- 7.5 cm, weight 73.2 +/- 5.6 kg) performed an incremental load test to determine maximal workload and several submaximal 30-min constant workloads for MLSS measurement on a rowing ergometer, a cycle ergometer, and on a speed-skating track. Maximal workload was higher (P < or = 0.05) in rowing (416.8 +/- 46.2 W) than in cling (358.6 +/- 34.4 W) and speed skating (383.5 +/- 40.9 W). The level of MLSS differed (P < or = 0.001) in rowing (3.1 +/- 0.5 mmol.l-1), cycling (5.4 +/- 1.0 mmol.l-1), and in speed skating (6.6 +/- 0.9 mmol.l-1). MLSS workload was higher (P < or = 0.05) in rowing (316.2 +/- 29.9 W) and speed skating (300.5 +/- 43.8 W) than in cycling (257.8 +/- 34.6 W). No differences (P > 0.05) in MLSS workload were found between speed skating and rowing. MLSS workload intensity as related to maximal workload was independent (P > 0.05) of the sports event: 76.2% +/- 5.7% in rowing, 71.8% +/- 4.1% in cycling, and 78.1% +/- 4.4% in speed skating. Changes in MLSS do not respond with MLSS workload, the MLSS workload intensity, or with the metabolic profile of the sports event. The observed differences in MLSS and MLSS workload may correspond to the sport-specific mass of working muscle.

  7. Determination of sub-microgram amounts of selenium in geological materials by atomic-absorption spectrophotometry with electrothermal atomisation after solvent extraction

    USGS Publications Warehouse

    Sanzolone, R.F.; Chao, T.T.

    1981-01-01

    An atomic-absorption spectrophotometric method with electrothermal atomisation has been developed for the determination of selenium in geological materials. The sample is decomposed with a mixture of nitric, perchloric and hydrofluoric acids and heated with hydrochloric acid to reduce selenium to selenium (IV). Selenium is then extracted into toluene from a hydrochloric acid - hydrobromic acid medium containing iron. A few microlitres of the toluene extract are injected into a carbon rod atomiser, using a nickel solution as a matrix modifier. The limits of determination are 0.2-200 p.p.m. of selenium in a geological sample. For concentrations between 0.05 and 0.2 p.p.m., back-extraction of the selenium into dilute hydrochloric acid is employed before atomisation. Selenium values for reference samples obtained by replicate analysis are in general agreement with those reported by other workers, with relative standard deviations ranging from 4.1 to 8.8%. Recoveries of selenium spiked at two levels were 98-108%. Major and trace elements commonly encountered in geological materials do not interfere. Arsenic has a suppressing effect on the selenium signals, but only when its concentration is greater than 1000 p.p.m. Nitric acid interferes seriously with the extraction of selenium and must be removed by evaporation in the sample-digestion step.

  8. High resolution chronology of late Cretaceous-early Tertiary events determined from 21,000 yr orbital-climatic cycles in marine sediments

    NASA Technical Reports Server (NTRS)

    Herbert, Timothy D.; Dhondt, Steven

    1988-01-01

    A number of South Atlantic sites cored by the Deep Sea Drilling Project (DSDP) recovered late Cretaceous and early Tertiary sediments with alternating light-dark, high-low carbonate content. The sedimentary oscillations were turned into time series by digitizing color photographs of core segments at a resolution of about 5 points/cm. Spectral analysis of these records indicates prominent periodicity at 25 to 35 cm in the Cretaceous intervals, and about 15 cm in the early Tertiary sediments. The absolute period of the cycles that is determined from paleomagnetic calibration at two sites is 20,000 to 25,000 yr, and almost certainly corresponds to the period of the earth's precessional cycle. These sequences therefore contain an internal chronometer to measure events across the K/T extinction boundary at this scale of resolution. The orbital metronome was used to address several related questions: the position of the K/T boundary within magnetic chron 29R, the fluxes of biogenic and detrital material to the deep sea immediately before and after the K/T event, the duration of the Sr anomaly, and the level of background climatic variability in the latest Cretaceous time. The carbonate/color cycles that were analyzed contain primary records of ocean carbonate productivity and chemistry, as evidenced by bioturbational mixing of adjacent beds and the weak lithification of the rhythmic sequences. It was concluded that sedimentary sequences that contain orbital cyclicity are capable of providing resolution of dramatic events in earth history with much greater precision than obtainable through radiometric methods. The data show no evidence for a gradual climatic deterioration prior to the K/T extinction event, and argue for a geologically rapid revolution at this horizon.

  9. An improved method for the determination of trace levels of arsenic and antimony in geological materials by automated hydride generation-atomic absorption spectroscopy

    USGS Publications Warehouse

    Crock, J.G.; Lichte, F.E.

    1982-01-01

    An improved, automated method for the determination of arsenic and antimony in geological materials is described. After digestion of the material in sulfuric, nitric, hydrofluoric and perchloric acids, a hydrochloric acid solution of the sample is automatically mixed with reducing agents, acidified with additional hydrochloric acid, and treated with a sodium tetrahydroborate solution to form arsine and stibine. The hydrides are decomposed in a heated quartz tube in the optical path of an atomic absorption spectrometer. The absorbance peak height for arsenic or antimony is measured. Interferences that exist are minimized to the point where most geological materials including coals, soils, coal ashes, rocks and sediments can be analyzed directly without use of standard additions. The relative standard deviation of the digestion and the instrumental procedure is less than 2% at the 50 ??g l-1 As or Sb level. The reagent-blank detection limit is 0.2 ??g l-1 As or Sb. ?? 1982.

  10. How events determine spreading patterns: information transmission via internal and external influences on social networks

    NASA Astrophysics Data System (ADS)

    Liu, Chuang; Zhan, Xiu-Xiu; Zhang, Zi-Ke; Sun, Gui-Quan; Hui, Pak Ming

    2015-11-01

    Recently, information transmission models motivated by the classical epidemic propagation, have been applied to a wide-range of social systems, generally assume that information mainly transmits among individuals via peer-to-peer interactions on social networks. In this paper, we consider one more approach for users to get information: the out-of-social-network influence. Empirical analyzes of eight typical events’ diffusion on a very large micro-blogging system, Sina Weibo, show that the external influence has significant impact on information spreading along with social activities. In addition, we propose a theoretical model to interpret the spreading process via both internal and external channels, considering three essential properties: (i) memory effect; (ii) role of spreaders; and (iii) non-redundancy of contacts. Experimental and mathematical results indicate that the information indeed spreads much quicker and broader with mutual effects of the internal and external influences. More importantly, the present model reveals that the event characteristic would highly determine the essential spreading patterns once the network structure is established. The results may shed some light on the in-depth understanding of the underlying dynamics of information transmission on real social networks.

  11. Stoichiometric Determination of Nitrate Fate in Agricultural Ecosystems during Rainfall Events

    PubMed Central

    Wang, Yiyao

    2015-01-01

    Ecologists have found a close relationship between the concentrations of nitrate (NO3-) and dissolved organic carbon (DOC) in ecosystems. However, it is difficult to determine the NO3- fate exactly because of the low coefficient in the constructed relationship. In the present paper, a negative power-function equation (r2 = 0.87) was developed by using 411 NO3- data points and DOC:NO3- ratios from several agricultural ecosystems during different rainfall events. Our analysis of the stoichiometric method reveals several observations. First, the NO3- concentration demonstrated the largest changes when the DOC:NO3- ratio increased from 1 to 10. Second, the biodegradability of DOC was an important factor in controlling the NO3- concentration of agricultural ecosystems. Third, sediment was important not only as a denitrification site, but also as a major source of DOC for the overlying water. Fourth, a high DOC concentration was able to maintain a low NO3- concentration in the groundwater. In conclusion, this new stoichiometric method can be used for the accurate estimation and analysis of NO3- concentrations in ecosystems. PMID:25849210

  12. Field Geology/Processes

    NASA Technical Reports Server (NTRS)

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

    1996-01-01

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

  13. Engineering Geology

    ERIC Educational Resources Information Center

    Hatheway, Allen W.

    1978-01-01

    Engineering geology remains a potpourri of applied classical geology, and 1977 witnessed an upswing in demand for these services. Traditional foundation-related work was slight, but construction related to national needs increased briskly. Major cities turned to concerns of transit waste-water treatment and solid-waste disposal. (Author/MA)

  14. 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.

  15. Physical geology

    SciTech Connect

    Skinner, B.; Porter, S.

    1987-01-01

    The book integrates current thinking on processes (plate techtonics, chemical cycles, changes throughout geologic time). It is an introduction to investigations into the way the earth works, how mountains are formed, how the atmosphere, hydrosphere, crust and mantle interact with each other. Treatments on climate, paleoclimatology and landscape evolution are included, as is a discussion on how human activity affects geological interactions.

  16. Engineering Geology

    ERIC Educational Resources Information Center

    Hatheway, Allen W.

    1978-01-01

    Engineering geology remains a potpourri of applied classical geology, and 1977 witnessed an upswing in demand for these services. Traditional foundation-related work was slight, but construction related to national needs increased briskly. Major cities turned to concerns of transit waste-water treatment and solid-waste disposal. (Author/MA)

  17. Geologic Time.

    ERIC Educational Resources Information Center

    Newman, William L.

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

  18. Using Earthquake Intensity Data to Determine Earthquake Locations and Magniitudes of PRE-1966 Events in the Rio Grande Rift Region

    NASA Astrophysics Data System (ADS)

    Galvan, P.; Castro, J.; Doser, D. I.

    2012-12-01

    Prior to the use of modern seismographs beginning in the mid-1960's, not much information exists on the location and magnitudes of earthquakes in the Rio Grande rift and surrounding regions of Colorado, New Mexico, west Texas, and Chihuahua, Mexico. However, a fair amount of intensity information is available for these earthquakes. Using procedures originally developed by Bakun and Wentworth (1997) we can use intensity information for well located, recent earthquakes as calibration events to develop intensity-distance attenuation models. The intensity attenuation models can then be used to determine the epicenters and magnitudes for the older events. Preliminary analysis of intensity data for recent events in the Rio Grande rift-southeastern Rocky Mountains area suggest this region has a similar intensity attenuation relationship to that determined by Bakun (2006) for the Basin and Range province. Intensity data for recent events in the eastern Colorado Plateau and westernmost Great Plains appears consistent with intensity attenuation models developed by Bakun and Hopper (2004) for eastern North America. We will use these attenuation models to determine the magnitudes and locations of pre-1966 events, with special emphasis on events occurring in the central Rio Grande rift between 1905 and 1950.

  19. A new determination of radii and limb parameters for Pluto and Charon from mutual event lightcurves

    NASA Technical Reports Server (NTRS)

    Young, Eliot F.; Binzel, Richard P.

    1994-01-01

    Over the past several years Pluto-Charon mutual events have yielded progressively more accurate estimates of Charon's orbital elements and the radii of Pluto and Charon (e.g., Buie, Tholen, and Horne, 1992). Analysis of the 1988 stellar occultation by Pluto indicates a radius for Pluto that is about 4%, or 50 km, larger than the mutual event radius of 1151 km. One possible explanation for the discrepancy is that the mutual event modeling treats Pluto and Charon as uniformly bright disks. If they are limb-darkened, the mutual event fits could underestimate their radii. In this paper we use an independent mutual event data set (Young and Binzel, 1992) to fit for Pluto and Charon's radii in a manner independent of either object's limb profile or albedo distribution. Our least-squares solution indicates that Pluto's radius is 1164 +/- 22.9 km and Charon's radius is 621 +/- 20.6 km.

  20. A new determination of radii and limb parameters for Pluto and Charon from mutual event lightcurves

    NASA Technical Reports Server (NTRS)

    Young, Eliot F.; Binzel, Richard P.

    1994-01-01

    Over the past several years Pluto-Charon mutual events have yielded progressively more accurate estimates of Charon's orbital elements and the radii of Pluto and Charon (e.g., Buie, Tholen, and Horne, 1992). Analysis of the 1988 stellar occultation by Pluto indicates a radius for Pluto that is about 4%, or 50 km, larger than the mutual event radius of 1151 km. One possible explanation for the discrepancy is that the mutual event modeling treats Pluto and Charon as uniformly bright disks. If they are limb-darkened, the mutual event fits could underestimate their radii. In this paper we use an independent mutual event data set (Young and Binzel, 1992) to fit for Pluto and Charon's radii in a manner independent of either object's limb profile or albedo distribution. Our least-squares solution indicates that Pluto's radius is 1164 +/- 22.9 km and Charon's radius is 621 +/- 20.6 km.

  1. Determination of aluminium, silicon and magnesium in geological matrices by delayed neutron activation analysis based on k0 instrumental neutron activation analysis.

    PubMed

    Baidoo, I K; Dampare, S B; Opata, N S; Nyarko, B J B; Akaho, E H K; Quagraine, R E

    2013-12-01

    In this work, concentrations of silicon, aluminium and magnesium in geological matrices were determined by Neutron Activation Analysis based on k0-IAEA software. The optimum activation and delay times were found to be 5 min and 15-20 min respectively for the determination of Si via (29)Si (n,p) (29)Al reaction. The adopted irradiation scheme did not work for the determination of magnesium. Each sample was irradiated under a thermal neutron flux density of 5.0 × 10(11) ncm(-2)s(-1). Cadmium covered activation indicated that a permanent epithermal irradiation site for research reactors would be very useful for routine determination of silicon in environmental samples.

  2. Exploring Geology

    NASA Astrophysics Data System (ADS)

    Geissman, John W.

    2008-09-01

    I am willing to bet a nice bottle of chardonnay that much of the Eos readership has lugged around, fondled, and fumbled through an introductory physical geology textbook of some form or another, once upon a time. Mine, in 1970, was Physical Geology, by Longwell, Flint, and Sanders, which I still have, by the way. Most of us know how ``classical'' physical geology textbooks have been organized: first, a broad overview of Earth processes, then several sections devoted to groups of more specific subjects (e.g., mineralogy, sedimentary rocks, and environments, with one chapter per subject), then several sections devoted to a synthesis of geologic processes in the context of plate tectonics, and finally, typically, a discussion of Earth resources and environment- related issues. Some relatively new textbooks have ventured into new pedagogical formats, for example, emphasizing how we know what we know (e.g., How Does Earth Work: Physical Geology and the Process of Science by Smith and Pun).

  3. Germline methylation patterns determine the distribution of recombination events in the dog genome.

    PubMed

    Berglund, Jonas; Quilez, Javier; Arndt, Peter F; Webster, Matthew T

    2014-12-19

    The positive-regulatory domain containing nine gene, PRDM9, which strongly associates with the location of recombination events in several vertebrates, is inferred to be inactive in the dog genome. Here, we address several questions regarding the control of recombination and its influence on genome evolution in dogs. First, we address whether the association between CpG islands (CGIs) and recombination hotspots is generated by lack of methylation, GC-biased gene conversion (gBGC), or both. Using a genome-wide dog single nucleotide polymorphism data set and comparisons of the dog genome with related species, we show that recombination-associated CGIs have low CpG mutation rates, and that CpG mutation rate is negatively correlated with recombination rate genome wide, indicating that nonmethylation attracts the recombination machinery. We next use a neighbor-dependent model of nucleotide substitution to disentangle the effects of CpG mutability and gBGC and analyze the effects that loss of PRDM9 has on these rates. We infer that methylation patterns have been stable during canid genome evolution, but that dog CGIs have experienced a drastic increase in substitution rate due to gBGC, consistent with increased levels of recombination in these regions. We also show that gBGC is likely to have generated many new CGIs in the dog genome, but these mostly occur away from genes, whereas the number of CGIs in gene promoter regions has not increased greatly in recent evolutionary history. Recombination has a major impact on the distribution of CGIs that are detected in the dog genome due to the interaction between methylation and gBGC. The results indicate that germline methylation patterns are the main determinant of recombination rates in the absence of PRDM9. © The Author(s) 2014. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  4. Germline Methylation Patterns Determine the Distribution of Recombination Events in the Dog Genome

    PubMed Central

    Berglund, Jonas; Quilez, Javier; Arndt, Peter F.; Webster, Matthew T.

    2015-01-01

    The positive-regulatory domain containing nine gene, PRDM9, which strongly associates with the location of recombination events in several vertebrates, is inferred to be inactive in the dog genome. Here, we address several questions regarding the control of recombination and its influence on genome evolution in dogs. First, we address whether the association between CpG islands (CGIs) and recombination hotspots is generated by lack of methylation, GC-biased gene conversion (gBGC), or both. Using a genome-wide dog single nucleotide polymorphism data set and comparisons of the dog genome with related species, we show that recombination-associated CGIs have low CpG mutation rates, and that CpG mutation rate is negatively correlated with recombination rate genome wide, indicating that nonmethylation attracts the recombination machinery. We next use a neighbor-dependent model of nucleotide substitution to disentangle the effects of CpG mutability and gBGC and analyze the effects that loss of PRDM9 has on these rates. We infer that methylation patterns have been stable during canid genome evolution, but that dog CGIs have experienced a drastic increase in substitution rate due to gBGC, consistent with increased levels of recombination in these regions. We also show that gBGC is likely to have generated many new CGIs in the dog genome, but these mostly occur away from genes, whereas the number of CGIs in gene promoter regions has not increased greatly in recent evolutionary history. Recombination has a major impact on the distribution of CGIs that are detected in the dog genome due to the interaction between methylation and gBGC. The results indicate that germline methylation patterns are the main determinant of recombination rates in the absence of PRDM9. PMID:25527838

  5. Determination of traces of Mo in soils and geological materials by solvent extraction of the molybdenum-thiocyanate complex and atomic absorption.

    PubMed

    Kim, C H; Owens, C M; Smythe, L E

    1974-06-01

    Comprehensive studies of the extraction of the molybdenum-thiocyanate complex with methyl isobutyl ketone have resulted in an improved method for the determination of traces of molybdenum in soils and geological materials by atomic-absorption spectroscopy. The method is applicable in the range 1-500 ppm Mo, with 1-g samples, giving relative standard deviations not exceeding about 8% at a level of 1 ppm. The limit of detection is 0.1 ppm. There are few interferences, and large quantities of iron are without effect.

  6. Mountain permafrost and recent Alpine rock-fall events: a GIS-based approach to determine critical factors and runout zones

    NASA Astrophysics Data System (ADS)

    Noetzli, J.; Hoelzle, M.; Haeberli, W.:

    2003-04-01

    Glacier retreat and permafrost changes, as related to climate change, are supposed to affect stability conditions of steep rock walls in cold mountain ranges. Several rock-fall events that have occurred in the European Alps during the 20th century (for example, the Brenva Glacier rock avalanches of 1920 and 1997 in the Aosta Valley or the recently developed instability in the Monte-Rosa east wall in the Anzasca Valley, both in the Italian Alps) are possibly related to warm permafrost. The presence of unfrozen water in partially ice-filled bedrock fissures is likely to lead to reduced shearing resistance. However, available knowledge about thermal, topographic and geological conditions under which such instabilities develop remains limited and needs quantitative investigation. Corresponding data can be used as a basis for GIS-based spatial modeling of critical factors or of combinations of factors. Such spatial models of critical rock-fall factors then serve as a basis for assessing hazard potentials that may evolve from periglacial rock falls in case of continued or even accelerated atmospheric temperature rise. In order to proceed into this direction, parameters are determined in a systematic study of known rock-fall events in the Alps. Surface temperatures of historically documented starting zones are estimated either by applying the ärules of thumb“ earlier developed for the Swiss Alps, by applying GIS-based spatial models such as PERMAMAP or by using the data of a 2001/2002 rock-temperature measurement campaign. Topographic factors such as slope, altitude or aspect are derived from DTMs. Altitude difference, length, overall slope and surface characteristics (glacier, moraines, turns etc.) of runout paths are also inventoried. Despite the relatively small number of events documented (around 20), first results can be given and first model runs of spatial patterns and potential runout zones can be presented from a selected test area in the Valais Alps

  7. Determining the hydraulic properties of saturated, low-permeability geological materials in the laboratory: Advances in theory and practice

    USGS Publications Warehouse

    Zhang, M.; Takahashi, M.; Morin, R.H.; Endo, H.; Esaki, T.; ,

    2002-01-01

    The accurate hydraulic characterization of low-permeability subsurface environments has important practical significance. In order to examine this issue from the perspective of laboratory-based approaches, we review some recent advancements in the theoretical analyses of three different laboratory techniques specifically applied to low-permeability geologic materials: constant-head, constant flow-rate and transient-pulse permeability tests. Some potential strategies for effectively decreasing the time required to confidently estimate the permeability of these materials are presented. In addition, a new and versatile laboratory system is introduced that can implement any of these three test methods while simultaneously subjecting a specimen to high confining pressures and pore pressures, thereby simulating in situ conditions at great depths. The capabilities and advantages of this innovative system are demonstrated using experimental data derived from Shirahama sandstone and Inada granite, two rock types widely encountered in Japan.

  8. Individual differences in visual imagery determine how event information is remembered.

    PubMed

    Sheldon, Signy; Amaral, Robert; Levine, Brian

    2017-03-01

    Individuals differ in how they mentally imagine past events. When reminiscing about a past experience, some individuals remember the event accompanied by rich visual images, while others will remember it with few of these images. In spite of the implications that these differences in the use of imagery have to the understanding of human memory, few studies have taken them into consideration. We examined how imagery interference affecting event memory retrieval was differently modulated by spatial and object imagery ability. We presented participants with a series of video-clips depicting complex events. Participants subsequently answered true/false questions related to event, spatial, or feature details contained in the videos, while simultaneously viewing stimuli that interfered with visual imagery processes (dynamic visual noise; DVN) or a control grey screen. The impact of DVN on memory accuracy was related to individual differences in spatial imagery ability. Individuals high in spatial imagery were less accurate at recalling details from the videos when simultaneously viewing the DVN stimuli compared to those low in spatial imagery ability. This finding held for questions related to the event and spatial details but not feature details. This study advocates for the inclusion of individual differences when studying memory processes.

  9. 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.

  10. A modification of the U.S. Geological Survey one-sixth order semiquantitative spectrographic method for the analysis of geologic materials that improves limits of determination of some volatile to moderately volatile elements

    USGS Publications Warehouse

    Detra, D.E.; Cooley, Elmo F.

    1988-01-01

    A modification of the one-sixth order semi-quantitative emission spectrographic method for the analysis of 30 elements in geologic materials (Grimes and Marranzino 1968) improves the limits of determination of some volatile to moderately volatile elements. The modification uses a compound-pendulum-mounted filter to regulate the amount of emitted light passing into the spectrograph. One hundred percent transmission of emitted light is allowed during the initial 20 seconds of the burn, then continually reduced to 40 percent over the next 32 seconds using the pendulum-mounted filter, and followed by an additional 68 seconds of burn time. The reduction of light transmission during the latter part of the burn decreases spectral background and the line emission of less volatile elements commonly responsible for problem-causing interferences. The sensitivity of the method for some geochemically important trace elements commonly determined in mineral exploration (Ag, As, Au, Be, Bi, Cd, Cr, Cu, Pb, Sb, Sn, and Zn) is improved up to five-fold under ideal conditions without compromising precision or accuracy

  11. Potential for timing high-energy marine inundation events in the recent geological past through age-dating of reef boulders in Fiji

    NASA Astrophysics Data System (ADS)

    Terry, James P.; Etienne, Samuel

    2014-12-01

    Transported coastal boulders have increasingly come to represent a valuable element of investigations within the broader framework of multi-proxy approaches applied to coastal hazard studies. Through a case study on Taveuni Island in Fiji, this paper outlines some approaches and hindrances to effective timing of prehistorical high-energy marine inundation events (storms and tsunamis) on tropical coastlines from the evidence of reef-platform carbonate boulders. Various sources of errors are outlined that investigators must consider when attempting to use carbonate boulder ages as a surrogate for timing past events. On Taveuni, uranium : thorium dates with a high level of precision (1-7 years) suggest that major inundation events have a return period of approximately 40-45 years since 1650 AD. Of particular importance, considerably different age dates are provided by coral samples sourced from the top and bottom (i.e. opposite faces) of individual boulders, so highlighting interpretation biases that must be avoided.

  12. Mathematical Geology.

    ERIC Educational Resources Information Center

    McCammon, Richard B.

    1979-01-01

    The year 1978 marked a continued trend toward practical applications in mathematical geology. Developments included work in interactive computer graphics, factor analysis, the vanishing tons problem, universal kriging, and resource estimating. (BB)

  13. Engineering Geology

    ERIC Educational Resources Information Center

    Lee, Fitzhugh T.

    1974-01-01

    Briefly reviews the increasing application of geologic principles, techniques and data to engineering practices in the areas of land use and zoning controls, resource management energy programs and other fields. (BR)

  14. Engineering Geology

    ERIC Educational Resources Information Center

    Lee, Fitzhugh T.

    1974-01-01

    Briefly reviews the increasing application of geologic principles, techniques and data to engineering practices in the areas of land use and zoning controls, resource management energy programs and other fields. (BR)

  15. Dynamics of pollutant discharge in combined sewer systems during rain events: chance or determinism?

    PubMed

    Hannouche, A; Chebbo, G; Joannis, C

    2014-01-01

    A large database of continuous flow and turbidity measurements cumulating data on hundreds of rain events and dry weather days from two sites in Paris (called Quais and Clichy) and one in Lyon (called Ecully) is presented. This database is used to characterize and compare the behaviour of the three sites at the inter-events scale. The analysis is probed through three various variables: total volumes and total suspended solids (TSS) masses and concentrations during both wet and dry weather periods in addition to the contributions of diverse-origin sources to event flow volume and TSS load values. The results obtained confirm the previous findings regarding the spatial consistency of TSS fluxes and concentrations between both sites in Paris having similar land uses. Moreover, masses and concentrations are proven to be correlated between Parisian sites in a way that implies the possibility of some deterministic processes being reproducible from one catchment to another for a particular rain event. The results also demonstrate the importance of the contribution of wastewater and sewer deposits to the total events' loads and show that such contributions are not specific to Paris sewer networks.

  16. Geology, summary

    NASA Technical Reports Server (NTRS)

    Sabins, F. F., Jr.

    1975-01-01

    Trends in geologic application of remote sensing are identified. These trends are as follows: (1) increased applications of orbital imagery in fields such as engineering and environmental geology - some specific applications include recognition of active earthquake faults, site location for nuclear powerplants, and recognition of landslide hazards; (2) utilization of remote sensing by industry, especially oil and gas companies, and (3) application of digital image processing to mineral exploration.

  17. Determination of Os by isotope dilution-inductively coupled plasma-mass spectrometry with the combination of laser ablation to introduce chemically separated geological samples

    NASA Astrophysics Data System (ADS)

    Sun, Yali; Ren, Minghao; Xia, Xiaoping; Li, Congying; Sun, Weidong

    2015-11-01

    A method was developed for the determination of trace Os in geological samples by laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) with the combination of chemical separation and preconcentration. Samples are digested using aqua regia in Carius tubes, and the Os analyte is converted into volatile OsO4, which is distilled and absorbed with HBr. The HBr solution is concentrated for further Os purification using the microdistillation technique. The purified Os is dissolved in 10 μl of 0.02% sucrose-0.005% H3PO4 solution and then evaporated on pieces of perfluoroalkoxy (PFA) film, resulting in the formation of a tiny object (< 3 × 104 μm2 superficial area). Using LA-ICP-MS measurements, the object can give Os signals at least 100 times higher than those provided by routine solution-ICP-MS while successfully avoiding the memory effect. The procedural blank and detection limit in the developed technique are 3.0 pg and 1.8 pg for Os, respectively when 1 g of samples is taken. Reference materials (RM) are analyzed, and their Os concentrations obtained by isotope dilution are comparable to reference or literature values. Based on the individual RM results, the precision is estimated within the range of 0.6 to 9.4% relative standard deviation (RSD), revealing that this method is applicable to the determination of trace Os in geological samples.

  18. Solid sampling high-resolution continuum source graphite furnace atomic absorption spectrometry for gold determination in geological samples after preconcentration onto carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Dobrowolski, Ryszard; Mróz, Agnieszka; Dąbrowska, Marzena; Olszański, Piotr

    2017-06-01

    A novelty method for the determination of gold in geological samples by solid sampling high-resolution continuum source graphite furnace atomic absorption spectrometry (SS HR CS GF AAS) after solid-phase extraction onto modified carbon nanotubes (CNT) was described. The methodology developed is based on solid phase extraction of Au(III) ions from digested samples to eliminate strong interference caused by iron compounds and problems related to inhomogeneities of the samples. The use of aqueous or solid standard for calibration was studied and the slope of calibration curve was the same for both of these modes. This statement indicates the possibility to perform the calibration of the method using aqueous standard solutions. Under optimum conditions the absolute detection limit for gold was equal to 2.24 · 10- 6 μg g- 1 while the adsorption capacity of modified carbon nanotubes was 264 mg g- 1. The proposed procedure was validated by the application of certified reference materials (CRMs) with different content of gold and different matrix, the results were in good agreement with certified values. The method was successfully applied for separation and determination of gold ions in complex geological samples, with precision generally better than 8%.

  19. [Evaluation of usefulness of summarised and weighted scale of negative life events to examine the determinants of adolescent health].

    PubMed

    Supranowicz, Piotr

    2011-01-01

    Numerous studies have shown that the occurrence of negative life events, especially in childhood and adolescence, increases the risk of developing mental and somatic disorders in future. The purpose of presented paper was to assess to what extent the severity of events determines health disorders and risk behaviours among adolescents. The study was conducted on a randomly selected sample of ten secondary school students in Warsaw in the three-year period. A questionnaire for data gathering was elaborated in Health Promotion and Postgraduate Education of the National Institute of Public Health - National Institute of Hygiene. The scale of negative life events consisted of 32 items covering: 1) changes in live and health of closed persons, 2) contact with the acts of a crime or incorrect, 3) problems concerning biological maturation, 4) interpersonal relations in the nearest surrounding, 5) financial and living conditions and 6) problems of learning. The average severity of events evaluated by the students was used to determine the weights of individual item. Weighted scale as well as summarised scale were applied to analysis. In addition, the questionnaire included questions on health, well-being, and risk behaviours and attitudes, as criterial indicators. Our study did not provide evidence that only the severity of negative life events determines the health disorders and taking risk behaviours. The both scales showed similar moderate correlation with most criterial indicators and explained 10% - 20% of variance of subjectively experienced health indicators (self-assessment of health status, physical, psychical and social well-being), 10% - 25% of risk behaviours and attitudes and only 1% - 7% of health disorders measured by objective indicators (sickness absence, staying at home or in hospital due to health disorders, contact with physician, taking medication). It seems that not the severity of negative life events but their cumulating determines health and

  20. Force Balance at the Magnetopause Determined with MMS: Application to Flux Transfer Events

    NASA Technical Reports Server (NTRS)

    Zhao, C.; Russell, C. T.; Strangeway, R. J.; Petrinec, S. M.; Paterson, W. R.; Zhou, M.; Anderson, B. J.; Baumjohann, W.; Bromund, K. R.; Chutter, M.; hide

    2016-01-01

    The Magnetospheric Multiscale mission (MMS) consists of four identical spacecraft forming a closely separated (less than or equal to 10 km) and nearly regular tetrahedron. This configuration enables the decoupling of spatial and temporal variations and allows the calculation of the spatial gradients of plasma and electromagnetic field quantities. We make full use of the well cross-calibrated MMS magnetometers and fast plasma instruments measurements to calculate both the magnetic and plasma forces in flux transfer events (FTEs) and evaluate the relative contributions of different forces to the magnetopause momentum variation. This analysis demonstrates that some but not all FTEs, consistent with previous studies, are indeed force-free structures in which the magnetic pressure force balances the magnetic curvature force. Furthermore, we contrast these events with FTE events that have non-force-free signatures.

  1. Albedos and spectral signatures determination and it connection to geological processes: Simile between Earth and other solar system bodies

    NASA Astrophysics Data System (ADS)

    Suarez, J.; Ochoa, L.; Saavedra, F.

    2017-07-01

    Remote sensing has always been the best investigation tool for planetary sciences. In this research have been used data of Surface albedo, electromagnetic spectra and satelital imagery in search of understanding glacier dynamics in some bodies of the solar system, and how it's related to their compositions and associated geological processes, this methodology is very common in icy moons studies. Through analytic software's some albedos map's and geomorphological analysis were made that allow interpretation of different types of ice in the glacier's and it's interaction with other materials, almost all the images were worked in the visible and infrared ranges of the spectrum; spectral data were later used to connect the reflectance whit chemical and reologic properties of the compounds studied. It have been concluded that the albedo analysis is an effective tool to differentiate materials in the bodies surfaces, but the application of spectral data is necessary to know the exact compounds of the glaciers and to have a better understanding of the icy bodies.

  2. Determination of selenium at trace levels in geologic materials by energy-dispersive X-ray fluorescence spectrometry

    USGS Publications Warehouse

    Wahlberg, J.S.

    1981-01-01

    Low levels of selenium (0.1-500 ppm) in both organic and inorganic geologic materials can be semiquantitatively measured by isolating Se as a thin film for presentation to an energy-dispersive X-ray fluorescence spectrometer. Suitably pulverized samples are first digested by fusing with a mixture of Na2CO3 and Na2O2. The fusion cake is dissolved in distilled water, buffered with NH4Cl, and filtered to remove Si and the R2O3 group. A carrier solution of Na2TeO4, plus solid KI, hydrazine sulfate and Na2SO3, is added to the filtrate. The solution is then vacuum-filtered through a 0.45-??m pore-size filter disc. The filter, with the thin film of precipitate, is supported between two sheets of Mylar?? film for analysis. Good agreement is shown between data reported in this study and literature values reported by epithermal neutron-activation analysis and spectrofluorimetry. The method can be made quantitative by utilizing a secondary precipitation to assure complete recovery of the Se. The X-ray method offers fast turn-around time and a reasonably high production rate. ?? 1981.

  3. 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.

  4. Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory : determination of nonpurgeable suspended organic carbon by wet-chemical oxidation and infrared spectrometry

    USGS Publications Warehouse

    Burkhardt, Mark R.; Kammer, James A.; Jha, Virendra K.; O'Mara-Lopez, Peggy G.; Woodworth, Mark T.

    1997-01-01

    Precision and accuracy results are described for the determination of nonpurgeable suspended organic carbon (SOC) by silver-filter filtration, wet-chemical oxidation, and infrared determination of hte resulting carbon dioxide (CO2) used at the U.S. Geological Survey's nationalWater Quality Laboratory. An aliquot of raw water isfiltered through a 0.45-micrometer silver filter. The trapped organic material is oxidized using phosphoric acid and potassium persulfate in a scaled glass ampule,and the rseulting CO2 is measured by an infrared CO2 detector. The amount of CO3 is proportional to the concentration of chemically oxidizable nonpurgeable organic carbon in the sample. The SOC method detection limit for routine analysis is 0.2 milligram per liter. The average percent recovery is 97.1 percent and the average standard deviation is 11 percent.

  5. A tool for determining duration of mortality events in archaeological assemblages using extant ungulate microwear

    PubMed Central

    Rivals, Florent; Prignano, Luce; Semprebon, Gina M.; Lozano, Sergi

    2015-01-01

    The seasonality of human occupations in archaeological sites is highly significant for the study of hominin behavioural ecology, in particular the hunting strategies for their main prey-ungulates. We propose a new tool to quantify such seasonality from tooth microwear patterns in a dataset of ten large samples of extant ungulates resulting from well-known mass mortality events. The tool is based on the combination of two measures of variability of scratch density, namely standard deviation and coefficient of variation. The integration of these two measurements of variability permits the classification of each case into one of the following three categories: (1) short events, (2) long-continued event and (3) two separated short events. The tool is tested on a selection of eleven fossil samples from five Palaeolithic localities in Western Europe which show a consistent classification in the three categories. The tool proposed here opens new doors to investigate seasonal patterns of ungulate accumulations in archaeological sites using non-destructive sampling. PMID:26616864

  6. A tool for determining duration of mortality events in archaeological assemblages using extant ungulate microwear.

    PubMed

    Rivals, Florent; Prignano, Luce; Semprebon, Gina M; Lozano, Sergi

    2015-11-30

    The seasonality of human occupations in archaeological sites is highly significant for the study of hominin behavioural ecology, in particular the hunting strategies for their main prey-ungulates. We propose a new tool to quantify such seasonality from tooth microwear patterns in a dataset of ten large samples of extant ungulates resulting from well-known mass mortality events. The tool is based on the combination of two measures of variability of scratch density, namely standard deviation and coefficient of variation. The integration of these two measurements of variability permits the classification of each case into one of the following three categories: (1) short events, (2) long-continued event and (3) two separated short events. The tool is tested on a selection of eleven fossil samples from five Palaeolithic localities in Western Europe which show a consistent classification in the three categories. The tool proposed here opens new doors to investigate seasonal patterns of ungulate accumulations in archaeological sites using non-destructive sampling.

  7. Features, Events, and Processes: Disruptive Events

    SciTech Connect

    J. King

    2004-03-31

    The primary purpose of this analysis is to evaluate seismic- and igneous-related features, events, and processes (FEPs). These FEPs represent areas of natural system processes that have the potential to produce disruptive events (DE) that could impact repository performance and are related to the geologic processes of tectonism, structural deformation, seismicity, and igneous activity. Collectively, they are referred to as the DE FEPs. This evaluation determines which of the DE FEPs are excluded from modeling used to support the total system performance assessment for license application (TSPA-LA). The evaluation is based on the data and results presented in supporting analysis reports, model reports, technical information, or corroborative documents that are cited in the individual FEP discussions in Section 6.2 of this analysis report.

  8. Late Paleoproterozoic-Neoproterozoic multi-rifting events in the North China Craton and their geological significance: A study advance and review

    NASA Astrophysics Data System (ADS)

    Zhai, Mingguo; Hu, Bo; Zhao, Taiping; Peng, Peng; Meng, Qingren

    2015-11-01

    An important Paleoproterozoic mobile belt event took place in the North China Craton (NCC), termed the Hutuo Movement. This event has been interpreted to represent cratonic reworking characterized by rifting-subduction-collision processes. The NCC then evolved into a stable platform or para-platform tectonic setting in Earth's middle age period more than ~ 1.0 Ga. Thick Late Paleoproterozoic-Neoproterozoic sedimentary sequences were extensively deposited on the early metamorphic basement. The major sedimentary basins include the Xiong'er aulacogen system in the south-central NCC, the Yan-Liao aulacogen system in the north-central NCC, the Northern marginal rift system in the northwestern NCC and the Eastern marginal rift system in the eastern NCC. The following four stages of magmatic activity are recognized in the Late Paleoproterozoic to Neoproterozoic interval: (1) ~ 1800 to 1780 Ma Xiong'er igneous province (XIP), (2) ~ 1720 to 1620 Ma anorogenic magmatic association, (3) ~ 1350 to 1320 Ma diabase sill swarms, and (4) ~ 900 Ma mafic dyke swarms. These four magmatic events suggest that the NCC was situated in an intra-plate setting for a long time from ~ 1.8 Ga to ~ 0.7 Ga or even younger, and the magmatic events were associated with multi-stage rifting activities. We document that the NCC was in a long-term extensional tectonic setting during Late Paleoproterozoic-Neoproterozoic era. The main ore deposits in this period are magmatic type iron deposits related to anorthosite-gabbro bodies, REE-Nb-Fe and Pb-Zn-Cu-Fe deposits related to Mesoproterozoic-Neoproterozoic rifts. Orogenic metal deposits are absent. There is no evidence indicating that the Grenville or other orogenic events affected the NCC. The reason for the absence of Grenvillian aged events in the NCC is probably because it was far from the edge of the Nuna supercontinent, if such a supercontinent did exist. There is another possibility that the Earth's middle age represented a particular tectonic

  9. Aspirin resistance in patients with acute coronary events: risk factors and prevalence as determined by whole blood multiple electrode aggregometry.

    PubMed

    Ibrahim, O; Maskon, O; Darinah, Noor; Raymond, A A; Rahman, M M

    2013-11-01

    To determine the prevalence of aspirin resistance and associated risk factors based on biochemical parameters using whole blood multiple electrode aggregometry. The study was conducted at the outpatients cardiology clinic of the Universiti Kebangsaan Malaysia Medical Centre (UKMMC) from August 2011 to February 2012. Subjects on aspirin therapy were divided into two groups; first-ever coronary event and recurrent coronary event. Aspirin resistance was measured by a Multiplate(®) platelet analyser. A total of 74 patients (63 male, 11 female), with a mean age of 57.93 ± 74.1years were enrolled in the study. The patients were divided into two groups -first-ever coronary event group (n=52) and recurrent coronary event group (n=22). Aspirin resistance was observed in 12 out of 74 (16%) of the study patients, which consisted of 11 patients from the first-ever coronary event group and one patient from the recurrent coronary event group. There were significant correlations between aspirin resistance and age (r = -0.627; p = 0.029), total cholesterol (r = 0.608; p = 0.036) and LDL (r = 0.694; p = 0.012). LDL was the main predictor for area under the curve (AUC) for aspirin resistance. However, there was no association between aspirin resistance and cardiovascular events in both groups in this study. Aspirin resistance was observed in 16% of the study population. LDL was the major predictor of aspirin resistance. No association was found in the study between aspirin resistance with recurrent coronary events.

  10. Geology and geochemistry of the Macheng Algoma-type banded iron-formation, North China Craton: Constraints on mineralization events and genesis of high-grade iron ores

    NASA Astrophysics Data System (ADS)

    Wu, Huaying; Niu, Xianglong; Zhang, Lianchang; Pirajno, Franco; Luo, Huabao; Qin, Feng; Cui, Minli; Wang, Changle; Qi, Min

    2015-12-01

    The Macheng iron deposit is located in the eastern Hebei province of the North China Craton (NCC). It is hosted in Neoarchean metamorphic rocks of Baimiaozi formation in the Dantazi Group, consisting of biotite-leptynite, plagioclase-gneiss, plagioclase-amphibolite, migmatite, migmatitic granite and quartz schist. Geochemical analyses of the host biotite leptynite and plagioclase amphibolites show that their protoliths are both volcanics, inferred to be trachytic basalt and basaltic andesite, respectively. Based on the geochemical signature of the host rocks, together with geology of the iron deposit, it is inferred that the Macheng BIF is an Algoma-type iron exhalative formation, formed in an arc-related basin in the Neoarchean. Post-Archean Australian Shale (PAAS)-normalized rare earth elements (REEs) plus yttrium (Y) concentrations of different BIF ores with gneissic, striated and banded structure in the Macheng deposit, show similar patterns with depletions in light rare earth elements (LREEs) and middle rare earth elements (MREEs) relative to heavy rare earth elements (HREEs) and with apparently positive La, Y and Eu anomalies. Y/Ho ratios of the gneissic, striated and banded BIF ores vary from 37 to 56. These geochemical features of the BIF ores reveal their affinity with the sea water and the presence of a high-temperature hydrothermal component, indicating that both the seawater and high temperature hydrothermal fluids derived from alteration of oceanic basalts and komatiites may contribute to formation of the Macheng BIF. Geological, mineralogical and geochemical studies of the Macheng deposit recognized two kinds of high-grade iron ores. One is massive oxidized high-grade ore (Fe2O3T = 74.37-86.20 wt.%), mainly consisting of hematite with some magnetite, which shows geochemical characteristics of the gneissic, striated and banded BIF ores. The other type is magnetite high-grade ore, also massive and consisting of magnetite, with distinct characteristics

  11. Sexual partnership types as determinant of HIV risk in South African MSM: an event-level cluster analysis.

    PubMed

    Sandfort, Theo; Yi, Huso; Knox, Justin; Reddy, Vasu

    2013-05-01

    While individual determinants of HIV risk among MSM have been widely studied, there is limited understanding of how relational characteristics determine sexual risk. Based on data collected among 300 South African men who have sex with men (MSM) and using cluster analysis, this study developed a typology of four partnership types: the "Race-Economic Similar," "Age-Race-Economic Discordant," "Non-regular Neighbourhood," and "Familiar" partnership types. Support for the meaningfulness of these types was found through associations of these partnership types with participant characteristics and characteristics of the last anal sex event. Furthermore, in a multivariate analysis, only partnership type independently predicted whether the last anal sex event was unprotected. Findings of the study illustrate the importance of taking into account the relational context in understanding unprotected sexual practices and present ways to target intervention efforts as well as identify relationship specific determinants of unprotected sex.

  12. Tsunami geology in paleoseismology

    USGS Publications Warehouse

    Yuichi Nishimura,; Jaffe, Bruce E.

    2015-01-01

    The 2004 Indian Ocean and 2011 Tohoku-oki disasters dramatically demonstrated the destructiveness and deadliness of tsunamis. For the assessment of future risk posed by tsunamis it is necessary to understand past tsunami events. Recent work on tsunami deposits has provided new information on paleotsunami events, including their recurrence interval and the size of the tsunamis (e.g. [187–189]). Tsunamis are observed not only on the margin of oceans but also in lakes. The majority of tsunamis are generated by earthquakes, but other events that displace water such as landslides and volcanic eruptions can also generate tsunamis. These non-earthquake tsunamis occur less frequently than earthquake tsunamis; it is, therefore, very important to find and study geologic evidence for past eruption and submarine landslide triggered tsunami events, as their rare occurrence may lead to risks being underestimated. Geologic investigations of tsunamis have historically relied on earthquake geology. Geophysicists estimate the parameters of vertical coseismic displacement that tsunami modelers use as a tsunami's initial condition. The modelers then let the simulated tsunami run ashore. This approach suffers from the relationship between the earthquake and seafloor displacement, the pertinent parameter in tsunami generation, being equivocal. In recent years, geologic investigations of tsunamis have added sedimentology and micropaleontology, which focus on identifying and interpreting depositional and erosional features of tsunamis. For example, coastal sediment may contain deposits that provide important information on past tsunami events [190, 191]. In some cases, a tsunami is recorded by a single sand layer. Elsewhere, tsunami deposits can consist of complex layers of mud, sand, and boulders, containing abundant stratigraphic evidence for sediment reworking and redeposition. These onshore sediments are geologic evidence for tsunamis and are called ‘tsunami deposits’ (Figs. 26

  13. Destination: Geology?

    NASA Astrophysics Data System (ADS)

    Price, Louise

    2016-04-01

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

  14. Geological "Ground Truth" of Sea-level Highstand Events During Warm Interglaciations (MIS 11 and 5e): Taking the Punch out of Proxy Precision

    NASA Astrophysics Data System (ADS)

    Hearty, P. J.

    2005-12-01

    High-resolution sea-level records for marine isotope stages (MIS) 11 and 5e from coastal outcrops in Bahamas, Bermuda, Hawaii, and Western Australia provide physical confirmation of extreme ice-melting events during Pleistocene interglacials. Field evidence indicates MIS 11 sea level rose in a series of oscillations to c. +20 m, while that of MIS 5e reached its maximum of +6-10 m. Because these were brief events (100s yrs), their true magnitude is generally muted or obscured in deep-sea oxygen isotope records; generally averaged over thousands of years by the combined effects of sampling, bioturbation, and sedimentation rates. Further unresolvable variables such as temperature and salinity further cloud the isotope proxy record. Thus, the tangible rock record is of greatest importance in understanding the nature of these extreme events. Geomorphology, sedimentary structures, taphonomy of and dating of organisms, and petrology provide ground truth at field sites. Sea-level highstands preserve terraces and benches by erosion and subsequent deposition of sub- and intertidal sediments. Fenestral porosity is a measure of intertidal wetting and drying of sand, while decimetre-scale, high-angle cross beds of poorly-sorted sand and gravel indicate shallow subtidal conditions. In situ coral heads describe similar subtidal conditions. Delicate, sometimes partially articulated skeletons of birds and reptiles in sea caves reveal a protected shoreline. An early generation of isopachous, fibrous cement verifies the presence of marine phreatic water over a sustained period of time. These features, often misinterpreted (McMurtry, 2004, AGU Fall Meeting, OS21E-06), categorically exclude emplacement by tsunami waves. Oceanic isotope records cannot produce an equivalent level of resolution of short, extreme events via (in terms of age, duration, rates of sea-level and ice-volume changes), thus shifting the `burden of proof' to proxy methods to identify such events. In our quest to

  15. Stratigraphy and geologic history of Mercury

    NASA Technical Reports Server (NTRS)

    Spudis, Paul D.; Guest, John E.

    1988-01-01

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

  16. Potential role of the ocean thermostat in determining regional differences in coral reef bleaching events

    NASA Astrophysics Data System (ADS)

    Kleypas, Joan A.; Danabasoglu, Gokhan; Lough, Janice M.

    2008-02-01

    Several negative feedback mechanisms have been proposed by others to explain the stability of maximum sea surface temperature (SST) in the western Pacific warm pool (WPWP). If these ``ocean thermostat'' mechanisms effectively suppress warming in the future, then coral reefs in this region should be less exposed to conditions that favor coral reef bleaching. In this study we look for regional differences in reef exposure and sensitivity to increasing SSTs by comparing reported coral reef bleaching events with observed and modeled SSTs of the last fifty years. Coral reefs within or near the WPWP have had fewer reported bleaching events relative to reefs in other regions. Analysis of SST data indicate that the warmest parts of the WPWP have warmed less than elsewhere in the tropical oceans, which supports the existence of thermostat mechanisms that act to depress warming beyond certain temperature thresholds.

  17. Methods for probabilistic assessments of geologic hazards

    SciTech Connect

    Mann, C.J.

    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 identical events or components contributing to complex processes or phenomena. In practice, however, data which would permit objective estimation of those probabilities of interest may not be adequate, or may not even exist. Another problem that arises normally, regardless of the extent of data, is that risk assessments involve estimating extreme values. Rarely are extreme values accurately predictable even when an empirical frequency distribution is established well by data. In the absence of objective methods for estimating probabilities of natural events or processes, subjective probabilities for the hazard must be established through Bayesian methods, expert opinion, or Delphi methods. Uncertainty of every probability determination must be stated for each component of an event, process, or phenomenon. These uncertainties also must be propagated through the quantitative analysis so that a realistic estimate of total uncertainty can be associated with each final probability estimate for a geologic hazard.

  18. Testing the global capabilities of the Antelope software suite: fast location and Mb determination of teleseismic events using the ASAIN and GSN seismic networks

    NASA Astrophysics Data System (ADS)

    Pesaresi, D.; Russi, M.; Plasencia, M.; Cravos, C.

    2009-04-01

    The Italian National Institute for Oceanography and Experimental Geophysics (Istituto Nazionale di Oceanografia e di Geofisica Sperimentale, OGS) is running the Antarctic Seismographic Argentinean Italian Network (ASAIN), made of 5 seismic stations located in the Scotia Sea region in Antarctica and in Argentina: data from these stations are transferred in real time to the OGS headquarters in Trieste (Italy) via satellite links. OGS is also running, in close cooperation with the Friuli-Venezia Giulia Civil Defense, the North East (NI) Italy seismic network, making use of the Antelope commercial software suite from BRTT as the main acquisition system. As a test to check the global capabilities of Antelope, we set up an instance of Antelope acquiring data in real time from both the regional ASAIN seismic network in Antarctica and a subset of the Global Seismic Network (GSN) funded by the Incorporated Research Institution for Seismology (IRIS). The facilities of the IRIS Data Management System, and specifically the IRIS Data Management Center, were used for real time access to waveform required in this study. Preliminary results over 1 month period indicated that about 82% of the earthquakes with magnitude M>5.0 listed in the PDE catalogue of the National Earthquake Information Center (NEIC) of the United States Geological Survey (USGS) were also correctly detected by Antelope, with an average location error of 0.05 degrees and average body wave magnitude Mb estimation error below 0.1. The average time difference between event origin time and the actual time of event determination by Antelope was of about 45': the comparison with 20', the IASPEI91 P-wave travel time for 180 degrees distance, and 25', the estimate of our test system data latency, indicate that Antelope is a serious candidate for regional and global early warning systems. Updated figures calculated over a longer period of time will be presented and discussed.

  19. Lithospheric Models of the Middle East to Improve Seismic Source Parameter Determination/Event Location Accuracy

    DTIC Science & Technology

    2012-09-01

    structure of Saudi Arabia through data collection from broadband stations. Figure 2. (Left) Map of Arabian Plate showing major tectonic ...State Award Nos. DE-AC52-07NA27344/24.2.3.2 and DOS_SIAA-11-AVC/NMA-1 ABSTRACT The Middle East is a tectonically complex and seismically...active region. The ability to accurately locate earthquakes and other seismic events in this region is complicated by tectonics , the uneven

  20. Do morphometric parameters and geological conditions determine chemistry of glacier surface ice? Spatial distribution of contaminants present in the surface ice of Spitsbergen glaciers (European Arctic).

    PubMed

    Lehmann, Sara; Gajek, Grzegorz; Chmiel, Stanisław; Polkowska, Żaneta

    2016-12-01

    The chemism of the glaciers is strongly determined by long-distance transport of chemical substances and their wet and dry deposition on the glacier surface. This paper concerns spatial distribution of metals, ions, and dissolved organic carbon, as well as the differentiation of physicochemical parameters (pH, electrical conductivity) determined in ice surface samples collected from four Arctic glaciers during the summer season in 2012. The studied glaciers represent three different morphological types: ground based (Blomlibreen and Scottbreen), tidewater which evolved to ground based (Renardbreen), and typical tidewater glacier (Recherchebreen). All of the glaciers are functioning as a glacial system and hence are subject to the same physical processes (melting, freezing) and the process of ice flowing resulting from the cross-impact force of gravity and topographic conditions. According to this hypothesis, the article discusses the correlation between morphometric parameters, changes in mass balance, geological characteristics of the glaciers and the spatial distribution of analytes on the surface of ice. A strong correlation (r = 0.63) is recorded between the aspect of glaciers and values of pH and ions, whereas dissolved organic carbon (DOC) depends on the minimum elevation of glaciers (r = 0.55) and most probably also on the development of the accumulation area. The obtained results suggest that although certain morphometric parameters largely determine the spatial distribution of analytes, also the geology of the bed of glaciers strongly affects the chemism of the surface ice of glaciers in the phase of strong recession.

  1. Moderately to Poorly Welded Tuff, Bishop, California: Geophysical and Geological Characterization to Determine the Source of Radar Scattering

    NASA Astrophysics Data System (ADS)

    Dinwiddie, C. L.; Grimm, R. E.; McGinnis, R. N.; Stillman, D. E.; Heggy, E.

    2006-12-01

    The National Research Council Decadal Study on Terrestrial Analogs to Mars recommended the Bishop Tuff exposed in the Volcanic Tableland (Bishop, California) as an analog site because some Martian volcanoes and the Stealth region of southwestern Tharsis are thought to be composed of pyroclastic deposits [1,2]. Contrary to our previous forecasts, which were based solely upon combined use of transient electromagnetic and vertical electrical soundings [3], the water table >100 m below the moderately welded, electrically resistive Bishop Tuff caprock cannot be imaged by low-frequency (12.5-50 MHz) ground penetrating radar (GPR) because of strong scattering and absorption attenuation [4,5]. We returned to the Volcanic Tableland to assess the source of near-surface scattering using differential GPS- based structural mapping, multielectrode resistivity profiling, rock and alluvium sample collection for specific gravity and EM property analyses, and higher-frequency GPR profiling. We used the 10-channel, 96 electrode Syscal Pro (IRIS) resistivity meter and the Sensors &Software pE 100 GPR and the GSSI SIR 3000 GPR with 50, 100, 200 MHz, and 270, 500, and 900 MHz antennas, respectively, to scan five 100-m-long parallel transects that were separated laterally by no more than 3.5 m. Initial results suggest that deformation in the form of polygonal cooling joints and at least one geologically mappable fault in the moderately welded caprock may be sources of near-surface scattering in radar profiles. These features, exposed at the surface, may be interpreted in the subsurface and should provide fluid pathways to pond percolating water or promote conduit flow. Discrete, subhorizontal signatures in radargrams may be indicative of localized primary cooling joints or secondary unloading joints. Ponding of water will promote erosion and dissolution both vertically and horizontally, ultimately further segmenting joint-bounded blocks of tuff. We observe these signatures in both

  2. 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.

  3. Geological Gyrocompass

    NASA Astrophysics Data System (ADS)

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

    1990-10-01

    The invention relates to a new and improved geologic mapping and surveying apparatus for providing accurate, dependable, and portable measurement of attitudes of planar surfaces in situations where magnetic compasses will not work. The invention provides a unique arrangement of the gyrocompass and power supply in a portable carrying case. A gyroscope is not dependent on the earth's magnetic field for a reference as is a magnetic compass. Therefore, the invention of a geological gyrocompass is immune to disturbances in the earth's magnetic field and nearly duplicates the Brunton compass accuracy but does not require an environment free of magnetic anomalies.

  4. Geology and petrology of the plutonic complexes in the Wadi Fizh area: Multiple magmatic events and segment structure in the northern Oman ophiolite

    NASA Astrophysics Data System (ADS)

    Adachi, Yoshiko; Miyashita, Sumio

    2003-09-01

    Multiple magmatic events are recorded in the gabbroic unit in the Fizh area of the northern Oman ophiolite. Gabbroic blocks intruded by sheeted dike complex and upper gabbros of the main crustal sequence show the oldest event. Gabbronorite sills in the gabbroic blocks are nearly coeval with the host gabbro. Wehrlitic intrusions (wehrlite I) mark the third event of magmatism. These three magmatic events occurred at the retreating (dying) ridge axis because all these rocks are intruded by dolerite dike swarm, which is generally regarded as a precursor of advancing ridge axis. The next stage of magmatism is a main phase of oceanic crust generation in this area. Wehrlite II and then gabbronorite dikes intrude the still hot main gabbro unit. All of these above rocks have similar signatures with respect to clinopyroxene compositions and covariations between plagioclase and mafic minerals, though slight differences are present in the compositional ranges and clinopyroxene compositions of each unit. After considerable cooling of the main gabbro unit, primitive basalt dikes intrude the main gabbro unit, which may correspond to the Lasail unit. Finally, the Fizh-South complex intrudes into considerably cooled crustal sequence, being below the brittle-plastic transition temperatures. The Fizh-South complex, which was regarded as a common wehrlitic intrusion, is significantly different from all of the above mentioned rocks, with respect to the covariation between plagioclase and associating mafic minerals, crystallization order, and clinopyroxene compositions. The clinopyroxenes are characterized by extremely low Ti and Na contents, comparable with those of the V2 unit (Alley volcanics), suggesting that the Fizh-South complex correlates with the plutonic facies of the V2 unit during arc stage. Layered gabbros in the Wadi Zabin area, about 10 km north of the Fizh area, may be a northern extension of the gabbro blocks of the Fizh area, because they are intruded by numerous

  5. Core evidence of paleoseismic events in Paleogene deposits of the Shulu Sag in the Bohai Bay Basin, east China, and their petroleum geologic significance

    NASA Astrophysics Data System (ADS)

    Zheng, Lijing; Jiang, Zaixing; Liu, Hui; Kong, Xiangxin; Li, Haipeng; Jiang, Xiaolong

    2015-10-01

    The Shulu Sag, located in the southwestern corner of the Jizhong Depression, Bohai Bay Basin of east China, is a NE-SW trending, elongate Cenozoic half-graben basin. The lowermost part of the third member of the Shahejie Formation in this basin is characterized by continental rudstone and calcilutite to calcisiltite facies. Based on core observation and regional geologic analysis, seismites are recognized in these lacustrine deposits, which include soft-sediment deformation structures (sedimentary dikes, hydraulic shattering, diapir structures, convolute lamination, load-flame structures, ball-and-pillow structures, loop bedding, and subsidence structures), synsedimentary faults, and seismoturbidites. In addition, mixed-source rudstones, consisting of the Paleozoic carbonate clasts and in situ calcilutite clasts in the lowermost submember of Shahejie 3, appear in the seismites, suggesting an earthquake origin. A complete representative vertical sequence in the lowermost part of the third member found in well ST1H located in the central part of the Shulu Sag shows, from the base to the top: underlying undeformed layers, synsedimentary faults, liquefied carbonate rocks, allogenetic seismoturbidites, and overlying undeformed layers. Seismites are widely distributed around this well and there are multiple sets of stacked seismites separated by undeformed sediment. The nearby NW-trending Taijiazhuang fault whose fault growth index is from 1.1 to 1.8 and the NNE-trending Xinhe fault with a fault growth index of 1.3-1.9 may be the source of the instability to create the seismites. These deformed sedimentary layers are favorable for the accumulation of oil and gas; for example, sedimentary dikes can cut through many layers and serve as conduits for fluid migration. Sedimentary faults and fractures induced by earthquakes can act as oil and gas migration channels or store petroleum products as well. Seismoturbidites and mixed-source rudstones are excellent reservoirs due to

  6. Determination of the QCD color factor ratio CA/CF from the scale dependence of multiplicity in three jet events

    NASA Astrophysics Data System (ADS)

    Gary, J. William

    2000-06-01

    I examine the determination of the QCD color factor ratio CA/CF from the scale evolution of particle multiplicity in e+e- three jet events. I fit an analytic expression for the multiplicity in three jet events to event samples generated with QCD multihadronic event generators. I demonstrate that a one parameter fit of CA/CF yields the expected result CA/CF=2.25 in the limit of asymptotically large energies if energy conservation is included in the calculation. In contrast, a two parameter fit of CA/CF and a constant offset to the gluon jet multiplicity, proposed in a recent study, does not yield CA/CF=2.25 in this limit. I apply the one parameter fit method to recently published data of the DELPHI experiment at the e+e- collider LEP at CERN and determine the effective value of CA/CF from this technique, at the finite energy of the Z0 boson, to be 1.74+/-0.03+/-0.10, where the first uncertainty is statistical and the second is systematic.

  7. Determination of silver, bismuth, cadmium, copper, lead, and zinc in geologic materials by atomic absorption spectrometry with tricaprylylmethylammonium chloride

    USGS Publications Warehouse

    Viets, J.G.

    1978-01-01

    Interferences commonly encountered in the determination of silver, bismuth, cadmium, copper, lead, and zinc at crustal abundance levels are effectively eliminated using a rapid, sensitive, organic extraction technique. A potassium chlorate-hydrochloric acid digestion solubilizes the metals not tightly bound in the silicate lattice of rocks, soils, and stream sediments. The six metals are selectively extracted into a 10% Aliquat 336-MIBK organic phase in the presence of ascorbic acid and potassium iodide. Metals in the organic extract are determined by flame atomic absorption spectrometry to the 0.02-ppm level for silver, cadmium, copper, and zinc and to the 0.2-ppm level for bismuth and lead with a maximum relative standard deviation of 18.8% for known reference samples. An additional hydrofluoric acid digestion may be used to determine metals substituted in the silicate lattice.

  8. Theoretical geology

    NASA Astrophysics Data System (ADS)

    Mikeš, Daniel

    2010-05-01

    Theoretical geology Present day geology is mostly empirical of nature. I claim that geology is by nature complex and that the empirical approach is bound to fail. Let's consider the input to be the set of ambient conditions and the output to be the sedimentary rock record. I claim that the output can only be deduced from the input if the relation from input to output be known. The fundamental question is therefore the following: Can one predict the output from the input or can one predict the behaviour of a sedimentary system? If one can, than the empirical/deductive method has changes, if one can't than that method is bound to fail. The fundamental problem to solve is therefore the following: How to predict the behaviour of a sedimentary system? It is interesting to observe that this question is never asked and many a study is conducted by the empirical/deductive method; it seems that the empirical method has been accepted as being appropriate without question. It is, however, easy to argument that a sedimentary system is by nature complex and that several input parameters vary at the same time and that they can create similar output in the rock record. It follows trivially from these first principles that in such a case the deductive solution cannot be unique. At the same time several geological methods depart precisely from the assumption, that one particular variable is the dictator/driver and that the others are constant, even though the data do not support such an assumption. The method of "sequence stratigraphy" is a typical example of such a dogma. It can be easily argued that all the interpretation resulting from a method that is built on uncertain or wrong assumptions is erroneous. Still, this method has survived for many years, nonwithstanding all the critics it has received. This is just one example of the present day geological world and is not unique. Even the alternative methods criticising sequence stratigraphy actually depart from the same

  9. Extracting mineral system event histories from geophysical and geochemical data in geologically complex terrain - an example from the southeastern Fennoscandian Shield.

    NASA Astrophysics Data System (ADS)

    Sorjonen-Ward, Peter; Kontinen, Asko; Lerssi, Jouni; Mertanen, Satu; Molnar, Ferenc; O'Brien, Hugh; Pohjolainen, Esa; Halla, Jaana; Korhonen, Fawna; Mattila, Jussi

    2015-04-01

    The mineral systems concept is intended to extend and inform exploration capability, through understanding processes of metal extraction, transport and precipitation within a well-defined architectural framework, as opposed to simple - or even sophisticated - targeting of geophysical or geochemical anomalies. Given that geophysical and geochemical data represent a summation of all events and processes that have affected a body of rock, the use of advanced inversion techniques could be impeded unless we can extract an accurate event history and derive a comprehensive understanding of the history of hydrothermal events and their structural framework, even in a qualitative sense. In ideal cases, we may be able to place age constraints using isotopes or paleomagnetism, if hydrothermal mineral reactions enhance (or disperse) geochemical and geophysical signals. Given a the tendency for deformation in the brittle regime to occur preferentially by reactivation of existing zones of weakness, we might also expect a progressive linear enhancement or dilution of anomalies, where fluid-flow is focused within permeable fault zones. We illustrate these issues through an analysis of event histories and their relationship to diverse mineralization styles and episodes in the southeastern part of the Fennoscandian Shield, where the oldest mineral systems are represented by orogenic gold deposits in Neoarchean greenstone belts and the youngest events are recorded locally by Paleozoic crystallization of uraninite in repeatedly reactivated fault zones. The Neoarchean Karelian craton was subjected to thermal reworking as the foreland terrain to the 1.9-1.8 Ga Svecofennian Orogeny, as demonstrated by resetting of K-Ar, Ar-Ar, Rb-Sr and locally Pb-Pb isotopic systems in feldspars and pyrite, both within gold deposits, and regionally. However, retention of Archean strain patterns and observations of the strain state of Proterozoifc dyke swarms indicate an essentially brittle response, with

  10. Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory; determination of methylene blue active substances by spectrophotometry

    USGS Publications Warehouse

    Burkhardt, Mark R.; Cinotto, Pete J.; Frahm, Galen W.; Woodworth, Mark T.; Pritt, Jeffrey W.

    1995-01-01

    A method for the determination of methylene blue active substances in whole-water samples by liquid-liquid extraction and spectrophotometric detection is described. Sulfate and sulfonate-based surfectants are reacted with methylene blue to form a blue-colored complex. The complex is extracted into chloroform, back-washed with an acidified phosphate-based buffer solution, and measured against external standards with a probe spectrophotometer. The method detection limt for routine analysis is 0.02 milligram per liter. The precision is plus/minus 10 percent relative standard deviation. The positive bias from nitrate and chloride and U.S. Geological Survey method O-3111-83 for methylene blue active substances is minized by adding a back-washing step.

  11. Determination of gold, indium, tellurium and thallium in the same sample digest of geological materials by atomic-absorption spectroscopy and two-step solvent extraction

    USGS Publications Warehouse

    Hubert, A.E.; Chao, T.T.

    1985-01-01

    A rock, soil, or stream-sediment sample is decomposed with hydrofluoric acid, aqua regia, and hydrobromic acid-bromine solution. Gold, thallium, indium and tellurium are separated and concentrated from the sample digest by a two-step MIBK extraction at two concentrations of hydrobromic add. Gold and thallium are first extracted from 0.1M hydrobromic acid medium, then indium and tellurium are extracted from 3M hydrobromic acid in the presence of ascorbic acid to eliminate iron interference. The elements are then determined by flame atomic-absorption spectrophotometry. The two-step solvent extraction can also be used in conjunction with electrothermal atomic-absorption methods to lower the detection limits for all four metals in geological materials. ?? 1985.

  12. Species interactions determine the spatial mortality patterns emerging in plant communities after extreme events.

    PubMed

    Liao, Jinbao; Bogaert, Jan; Nijs, Ivan

    2015-06-08

    Gap disturbance is assumed to maintain species diversity by creating environmental heterogeneity. However, little is known about how interactions with neighbours, such as competition and facilitation, alter the emerging gap patterns after extreme events. Using a spatially explicit community model we demonstrate that negative interactions, especially intraspecific competition, greatly promote both average gap size and gap-size diversity relative to positive interspecific interaction. This suggests that competition would promote diversity maintenance but also increase community invasibility, as large gaps with a wide size variety provide more diverse niches for both local and exotic species. Under interspecific competition, both gap metrics interestingly increased with species richness, while they were reduced under intraspecific competition. Having a wider range of species interaction strengths led to a smaller average gap size only under intraspecific competition. Increasing conspecific clumping induced larger gaps with more variable sizes under intraspecific competition, in contrast to interspecific competition. Given the range of intraspecific clumping in real communities, models or experiments based on randomly synthesized communities may yield biased estimates of the opportunities for potential colonizers to fill gaps. Overall, our "static" model on gap formation offers perspectives to better predict recolonization opportunity and thus community secondary succession under extreme event regimes.

  13. Species interactions determine the spatial mortality patterns emerging in plant communities after extreme events

    PubMed Central

    Liao, Jinbao; Bogaert, Jan; Nijs, Ivan

    2015-01-01

    Gap disturbance is assumed to maintain species diversity by creating environmental heterogeneity. However, little is known about how interactions with neighbours, such as competition and facilitation, alter the emerging gap patterns after extreme events. Using a spatially explicit community model we demonstrate that negative interactions, especially intraspecific competition, greatly promote both average gap size and gap-size diversity relative to positive interspecific interaction. This suggests that competition would promote diversity maintenance but also increase community invasibility, as large gaps with a wide size variety provide more diverse niches for both local and exotic species. Under interspecific competition, both gap metrics interestingly increased with species richness, while they were reduced under intraspecific competition. Having a wider range of species interaction strengths led to a smaller average gap size only under intraspecific competition. Increasing conspecific clumping induced larger gaps with more variable sizes under intraspecific competition, in contrast to interspecific competition. Given the range of intraspecific clumping in real communities, models or experiments based on randomly synthesized communities may yield biased estimates of the opportunities for potential colonizers to fill gaps. Overall, our “static” model on gap formation offers perspectives to better predict recolonization opportunity and thus community secondary succession under extreme event regimes. PMID:26054061

  14. Geologic Time.

    ERIC Educational Resources Information Center

    Albritton, Claude C., Jr.

    1984-01-01

    Discusses the historical development of the concept of geologic time. Develops the topic by using the major discoveries of geologists, beginning with Steno and following through to the discovery and use of radiometric dating. An extensive reference list is provided. (JM)

  15. City Geology.

    ERIC Educational Resources Information Center

    Markle, Sandra

    1989-01-01

    This article provides information on the evolution of the building material, concrete, and suggests hands-on activities that allow students to experience concrete's qualities, test the heat absorbency of various ground surface materials, discover how an area's geology changes, and search for city fossils. A reproducible activity sheet is included.…

  16. Geologic Time.

    ERIC Educational Resources Information Center

    Albritton, Claude C., Jr.

    1984-01-01

    Discusses the historical development of the concept of geologic time. Develops the topic by using the major discoveries of geologists, beginning with Steno and following through to the discovery and use of radiometric dating. An extensive reference list is provided. (JM)

  17. Mantle exhumation and sequence of magmatic events in the Magnaghi-Vavilov Basin (Central Tyrrhenian, Italy): New constraints from geological and geophysical observations

    NASA Astrophysics Data System (ADS)

    Prada, M.; Ranero, C. R.; Sallarès, V.; Zitellini, N.; Grevemeyer, I.

    2016-10-01

    The Tyrrhenian basin opened in the Neogene following the E-SE retreat of the Appenines-Calabrian subduction system and the subsequent back-arc extension of an orogenic crust. The resultant crustal structure includes a complex distribution of continental, back-arc magmatism, and mantle-exhumation domains. A clear example of this complex structure is found in the central and deepest part of the basin (i.e. Magnaghi-Vavilov sub-basin) where geophysical data supported that the bulk of the basement is composed of partially serpentinised peridotite representing exhumed mantle rocks, and intruded by basalts forming low ridges and volcanic edifices. However, those data sets cannot univocally demonstrate the widespread presence of serpentinised mantle rocks, let alone the percentage of serpentinisation. Here, we use S-wave arrivals and available geological information to further constrain the presence of mantle serpentinisation. Travel times of converted S-waves were used to derive the overall Vp/Vs and Poisson's ratio (σ), as well as S-wave velocity of the basement in the Magnaghi-Vavilov Basins. This analysis reveals Vp/Vs ≈ 1.9 (σ ≈ 0.3) that strongly supports a serpentinised peridotite forming the basement under the basins, rather than oceanic-type gabbro/diabase. P-wave velocity models is later used to quantify the amount of serpentinisation from fully serpentinised (up to 100%) at the top of the basement to < 10% at 5-7 km deep, with a depth distribution similar to continent-ocean Transition zones at magma-poor rifted margins. Seismic reflection profiles show normal faulting at either flank of the Magnaghi-Vavilov Basin that is potentially responsible for the onset of serpentinisation and later mantle exhumation. These results, together with basement sampling information in the area, suggests that the late stage of mantle exhumation was accompanied or soon followed by the emplacement of MOR-type basalts forming low ridges that preceded intraplate volcanism

  18. Late Quaternary environmental and human events at En Gedi, reflected by the geology and archaeology of the Moringa Cave (Dead Sea area, Israel)

    NASA Astrophysics Data System (ADS)

    Lisker, Sorin; Porat, Roi; Davidovich, Uri; Eshel, Hanan; Lauritzen, Stein-Erik; Frumkin, Amos

    2007-09-01

    The Moringa Cave within Pleistocene sediments in the En Gedi area of the Dead Sea Fault Escarpment contains a sequence of various Pleistocene lacustrine deposits associated with higher-than-today lake levels at the Dead Sea basin. In addition it contains Chalcolithic remains and 5th century BC burials attributed to the Persian period, cemented and covered by Late Holocene travertine flowstone. These deposits represent a chain of Late Pleistocene and Holocene interconnected environmental and human events, echoing broader scale regional and global climate events. A major shift between depositional environments is associated with the rapid fall of Lake Lisan level during the latest Pleistocene. This exposed the sediments, providing for cave formation processes sometime between the latest Pleistocene (ca. 15 ka) and the Middle Holocene (ca. 4500 BC), eventually leading to human use of the cave. The Chalcolithic use of the cave can be related to a relatively moist desert environment, probably related to a shift in the location of the northern boundary of the Saharo-Arabian desert belt. The travertine layer was U-Th dated 2.46 ± 0.10 to 2.10 ± 0.04 ka, in agreement with the archaeological finds from the Persian period. Together with the inner consistency of the dating results, this strongly supports the reliability of the radiometric ages. The 2.46-2.10 ka travertine deposition within the presently dry cave suggests a higher recharge of the Judean Desert aquifer, correlative to a rising Dead Sea towards the end of the 1st millennium BC. This suggests a relatively moist local and regional climate facilitating human habitation of the desert.

  19. Chronostratigraphic calibration of late Neogene, northeast pacific Planktic foraminiferal events: Geological applications to the Plio-Pleistocene of the Ventura basin, California

    SciTech Connect

    Lagoe, M.B. )

    1990-05-01

    An integrated chronostratigraphy of late Neogene active margin basins of the northeastern Pacific Ocean is developed by calibrating the temperature of north Pacific planktic foraminiferal evolutionary datums and paleoclimatically controlled coiling shifts of Neogloboquadrina pachyderma with paleomagnetic, radiometric, and isotopic stratigraphies. This regional chronostratigraphic framework is then adapted to individual sedimentary basins. Ongoing work in the Ventura basin illustrates such an application. Planktic foraminiferal events at Balcom, Wheeler, and Santa Paula canyons are calibrated against paleomagnetic stratigraphy and radiometrically dated ash layers. This calibration agrees with and supplements previously derived regional calibrations. In particular, several coiling shifts of N. pachyderma and the last occurrence datums of Neogloboquadrina asanoi and Neogloboquadrina humerosa appear most useful in this area. These events provide high-resolution chronostratigraphic control between approximately 2.6 and 0.7 Ma in the central Ventura basin. Such chronostratigraphic control is an integral part of geohistory analysis, an application of which is presented to illustrate the utility of the integrated chronostratigraphic framework. Geohistory analysis of the Balcom and Wheeler canyon sections is used to reconstruct stratigraphic evolution north and south of the Oakridge Fault during deposition of the Pico Formation. Both sections show rapid subsidence during the Repettian, slower subsidence or possible uplift during the Venturian, and renewed subsidence during the Wheelerian. These histories do differ in several respects and a comparison of subsidence, uplift, and rock accumulation rates indicates that the fault was a normal fault, down to the north, through most of its Pliocene-Pleistocene history, being reactivated as a high-angle reverse fault only during the late Pleistocene.

  20. Chronostratigraphic calibration of late Neogene, northeast pacific planktic foraminiferal events: Geological applications to the Pliocene-Pleistocene of the Ventura basin, California

    SciTech Connect

    Lagoe, M.B. )

    1990-05-01

    An integrated chronostratigraphy of late Neogene active margin basins of the northeastern Pacific Ocean is developed by calibrating temperature north Pacific planktic foraminiferal evolutionary datums and paleoclimatically controlled coiling shifts of Neogloboquadrina pachyderma with paleomagnetic, radiometric, and isotopic stratigraphies. This regional chronostratigraphic framework is then adapted to individual sedimentary basins. Ongoing work in the Ventura basin illustrates such an application. Planktic foraminiferal events at Balcom, Wheeler, and Santa Paula canyons are calibrated against paleomagnetic stratigraphy and radiometrically dated ash layers. This calibration agrees with and supplements previously derived regional calibrations. In particular, several coiling shifts of N. pachyderma and the last occurrence datums of Neogloboquadrina asanoi and Noeglobouadrina humerosa appear most useful in this area. These events provide high-resolution chronostratigraphic control between approximately 2.6 and 0.7 Ma in the central Ventura basin. Such chronostratigraphic control is an integral part of geohistory analysis, an application of which is presented to illustrate the utility of the integrated chronostratigraphic framework. Geohistory analysis of the Balcom and Wheeler Canyon sections is used to reconstruct stratigraphic evolution north and south of the Oakridge fault during deposition of the Pico Formation. Both sections show rapid subsidence during the Repettian, slower subsidence or possible uplift during the Venturian, and renewed subsidence during the Wheelarian. These histories do differ in several respects and a comparison of subsidence, uplift, and rock accumulation rates indicates that the fault was a normal fault, down to the north, through most of its Pliocene-Pleistocene history, being reactivated as a high-angle reverse fault only during the late Pleistocene.

  1. Determination of arsenic in geological materials by x-ray fluorescence spectrometry after solvent extraction and deposition on a filter

    USGS Publications Warehouse

    Hubert, A.E.

    1983-01-01

    Rock, soil, or sediment samples are decomposed with a mixture of nitric and sulphuric adds. After reduction from arsenic(V) with ammonium thiosulphate, arsenic(III) is extracted as the chlorocomplex into benzene from a sulphuric-hydrochloric acid medium. The benzene solution is transferred onto a filter-paper disc impregnated with a solution of sodium bicarbonate and potassium sodium tartrate, and the benzene allowed to evaporate. The arsenic present is determined by X-ray fluorescence. In a 0.5-g sample, 1-1000 ppm of arsenic can be determined. The close proximity of the lead L?? peak (2?? 48.73??), to the arsenic K?? peak (2?? 48.83??) does not cause any interference, because lead is not extracted under the experimental conditions. Arsenic values obtained are in agreement with those reported for various reference samples. ?? 1983.

  2. Determination of platinum and palladium in geological materials by neutron-activation analysis after fire-assay preconcentration

    USGS Publications Warehouse

    Rowe, J.J.; Simon, F.O.

    1971-01-01

    Fire-asay preconcentration followed by neutron-activation analysis permits the determination of as little as 0.5 ppM of platinum and 0.5 ppM of palladium on a 20-g sample. Platinum and palladium are separated with carriers and beta-counted. Results for the platinum and palladium content of seven U.S.G.S. standard rocks are presented. ?? 1971.

  3. Expressions to determine temperatures and emission measures for solar X-ray events from GOES measurements

    NASA Technical Reports Server (NTRS)

    Thomas, R. J.; Starr, R.; Crannell, C. J.

    1984-01-01

    Expressions which give the effective color temperatures and corresponding emission measures for solar X-ray events observed with instruments onboard any of the GOES satellites are developed. Theoretical spectra were used to simulate the solar X-ray input at a variety of plasma temperatures. These spectra were folded through the wavelength dependent transfer functions for the two GOES detectors. The resulting detector responses and their ratio as a function of plasma temperature were then fit with simple analytic curves. Over the entire range between 5 and 30 million degrees, these fits reproduce the calculated color temperatures within 2% and the calculated emission measures within 5%. With the theoretical spectra, similar expressions for any pair of broadband X-ray detectors whose sensitivities are limited to wavelengths between 0.2 and 100 A are calculable.

  4. Contrasting Flow Events in Chryse and Acidalia Planitiae, Mars, as Determined Through Landform Mapping and Spatial Analyses

    NASA Astrophysics Data System (ADS)

    Skinner, J. A.; Fergason, R. L.

    2010-12-01

    The formation of “mottled” albedo surfaces in the Martian northern plains have remained enigmatic since their initial observation in Mariner 9 and Viking Orbiter data sets. We re-assess the geologic evolution of these materials in Chryse and Acidalia Planitiae by mapping and analyzing the spatial distribution of their characteristic landforms, including lobate margins and pitted cone fields. Bright lobes are defined by thin, concentric margins that abut, surround, and link decameter high knobs. These lobes range from 5.4 to 129.7 km long (24.3 km mean) and are located marginal to Chryse Planitia between -3291 and -5009 m elevation (-4050 m mean). Dark lobes are defined by thick, digitate margins that are discontinuous, self-overlapping, and often levee-bound. These lobes range from 6.5 to 95.5 km long (28.0 km mean) and are located near the center of Acidalia Planitia between -3602 and -5169 m elevation (-4627 m mean). Lobe orientations are strongly bi-modal, with bright lobes facing west-southwest (245°) and the dark lobes facing northeast (41°). Two populations of pitted cones pervasively occur in smooth to undulating bright plains adjacent to (or northward of) bright lobes. High-density fields are defined by irregularly-shaped, coalesced pitted cones that stand <10 m above surrounding plains, and occur ~1 per km2. Low-density fields are defined by quasi-circular, smooth-sided domes and cones that stand >20 m above surrounding plains, and occur ~0.1 per km2. The latter occur in plains units that embay and bury lower standing, high-density fields. Thermal radiance, morphology, spatial orientation, and cross-cutting relationships clearly discriminate two discrete and overlapping (though unrelated) geologic units that were emplaced through contrasting processes. We interpret dark lobes as vestige digitate terminations of debris flows sourced from circum-Chryse fractures and channels and light lobes as overlapping layers of relatively block-free sediment

  5. Simplified method for the determination of Ru, Pd, Re, Os, Ir and Pt in chromitites and other geological materials by isotope dilution ICP-MS and acid digestion.

    PubMed

    Meisel, T; Moser, J; Fellner, N; Wegscheider, W; Schoenberg, R

    2001-03-01

    A method for the determination of low Ru, Pd, Re, Os, Ir and Pt abundances in geological reference materials by isotope dilution inductively coupled plasma mass spectrometry (ICP-MS) after acid digestion in a high pressure asher (HPA-S) is presented. The digestion technique is similar to that using Carius tubes but easier to handle and reaches higher temperatures. Osmium can be determined as OsO4 with ICP-MS directly after digestion through a sparging technique. The remaining elements are preconcentrated by means of anion column chromatography. The resin is digested directly without elution leading to high yields but this causes problems if Zr is present at higher levels in the silicate rich materials. The analytical results for international platinum group element (PGE) reference materials, chromitite CHR-Bkg, basalt TDB-1 and gabbro WGB-1, are presented and compared with literature data, demonstrating the validity of the described method. Although higher in concentration, PGEs determined for reference material WGB-1 were worse than for TDB-1 indicating a more inhomogeneous distribution of the platinum group mineral phases. The low PGE abundance chromitite standard, CHR-Bkg, is likely to be homogeneous for Ru, Re, Os and Ir and is recommended as a reference material for the study of chromitites. Detection limits (3s x total procedure blank) range from 0.012 ng (Re and Os) to 0.77 ng (Pt), which could be further improved by applying higher quality acids.

  6. In situ Th and U isotope determinations of low-U geological samples using laser ablation single-collector sector-field ICPMS

    NASA Astrophysics Data System (ADS)

    Mertz-Kraus, R.; Jochum, K. P.; Sharp, W. D.; Stoll, B.; Weis, U.; Andreae, M. O.

    2009-12-01

    In situ spatially resolved U-series dating of geological and biological silicates, phosphates and carbonates (e.g., bone, speleothem, coral, and pedogenic silica and carbonate), facilitates measurement of the rates of natural processes (e.g., precipitation, crystallization) during the past 500,000 years. We present a LA-ICPMS technique for precise and accurate determination of Th and U isotopic ratios applicable to samples with U concentrations as low as 0.4 µg/g. Previously, in situ U-series determinations have been done using multi-collector ICPMS. We use a single-collector sector-field ICPMS connected to a 213 Nd:YAG laser ablation system. Precision and accuracy were determined for different matrices, such as synthetic NIST SRM 612, diverse silicate MPI-DING and USGS reference glasses, 91500 zircon, and a travertine previously analyzed by TIMS.230Th and 234U (~0.00001 to 0.0001 µg/g), required laser tracks up to 1800 µm long, rastering over a 400 x 400 µm square and measurement times of 5 to 25 minutes. We applied corrections for background (< 0.2 cps), the tails of 232Th, 235U and 238U peaks on 230Th and 234U (0.1 to 6 cps corresponding to a proportion of 0.3 to 30 % of the measured peak for 232Th and 238U concentrations of 0.003 to 10 µg/g), instrumental mass fractionation (~1 % per atomic mass unit), and differences in element sensitivity of Th and U using the certified values of the reference glasses.230Th/238U and 234U/238U determinations varies between 1.6 and 5 % depending on the extent of peak tailing corrections. We obtained 230Th/238U = 1.65 x 10-5 and 234U/238U = 5.29 x 10-5 for BCR-2G (1.7 µg/g U, 5.9 µg/g Th) which agree within 2 % and 4 %, respectively, with TIMS values (Matthews et al., 2008). For the travertine (2.5 µg/g U, 0.003 µg/g Th) the mean values for four scans (~0.14 mg sample each) are 230Th/238U = 2.47 x 10-5 and 234U/238U = 7.49 x 10-5, within 2 % of TIMS values. Matthews K. et al. (2008), Evaluation of Solid Geologic

  7. Microwave-assisted extraction and ultrasonic slurry sampling procedures for cobalt determination in geological samples by electrothermal atomic absorption spectroscopy.

    PubMed

    Felipe-Sotelo, M; Carlosena, A; Fernández, E; López-Mahía, P; Muniategui, S; Prada, D

    2004-06-17

    Slurry sampling is compared to microwave-assisted acid digestion for cobalt determination in soil/sediment samples by electrothermal atomic absorption spectrometry (ETAAS). Furnace temperature programs and appropriate amounts of three chemical modifiers were optimised in order to get the highest signals and good separations between the atomic and background signals. Using nitric acid (0.5% (v/v)) as liquid medium, no chemical modifier was needed. The detection limit, based on integrated absorbance, was 0.04mugg(-1) for digests and slurries. Within-batch precision and analytical recoveries were satisfactory for both procedures. Accuracy was tested by analysing a reference soil and a sediment from IRMM. The methods were further compared employing a set of roadside soils and estuarine sediments. As no significant differences (95% confidence) were found, practical analytical properties were suggested in order to select one of them.

  8. Ages of igneous and hydrothermal events in the Round Mountain and Manhattan gold districts, Nye County, Nevada.

    USGS Publications Warehouse

    Shawe, D.R.; Marvin, R.F.; Andriessen, P.A.M.; Mehnert, H.H.; Merritt, V.M.

    1986-01-01

    Isotopic age determinations of rocks and minerals separated from them are applied to refining and correlating the geological history of igneous and mineralizing events in a part of the Basin and Range province. -G.J.N.

  9. Effect of weather and time on trauma events determined using emergency medical service registry data.

    PubMed

    Lin, Li-Wei; Lin, Hsiao-Yu; Hsu, Chien-Yeh; Rau, Hsiao-Hsien; Chen, Ping-Ling

    2015-09-01

    Trauma admissions are associated with weather and temporal factors; however, previous study results regarding these factors are contradictory. We hypothesised that weather and temporal factors have different effects on specific trauma events in an emergency medical service (EMS) system. EMS data from January 1, 2009, to December 31, 2010, were obtained from the fire department of Taipei City and associated with the local weather data. EMS trauma events were categorised into total trauma, traffic accidents (TAs), motorbike accidents (MBAs), and falls. Hourly data on trauma patients were analysed using the zero-inflated Poisson model. The hourly incidence of total trauma increased with the magnitude of precipitation (incidence rate ratio [IRR]=1.06, 1.09, and 1.11 in light, moderate, and heavy rain, respectively), and this effect was more prominent in fall patients than in patients with other injuries (IRR=1.07, 1.21, and 1.32). However, the hourly incidence of TAs and MBAs was associated only with light rain (IRR=1.11 and 1.06, respectively). An hour of sunshine exposure was associated with an increase in the hourly incidence of all groups, and higher temperatures were associated with an increased hourly incidence of total trauma, TAs, and MBAs, but not falls. The hourly incidence of falls increased only in late fall and winter. Compared with the hourly incidence between 3 am and 7 am, the hourly incidence of all groups plateaued between 7 am and 11 pm and declined from 11 pm to 3 am. During the plateau period, 2 peaks in the incidence of TAs (IRR=5.03 and 5.07, respectively) and MBAs (IRR=5.81 and 5.51, respectively) were observed during 7-11 am and 3-7 pm. The hourly incidence of total trauma, TAs, and MBAs plateaued during workdays, peaked on Fridays, declined on Saturdays, and troughed on Sundays. The incidence of falls increased only on Mondays (IRR=1.09). Weather and temporal factors had different impacts on the incidence of traffic-related accidents and falls

  10. Instrument for determining coincidence and elapse time between independent sources of random sequential events

    NASA Technical Reports Server (NTRS)

    Clemmons, J. I., Jr. (Inventor)

    1983-01-01

    An instrument that receives pulses from a primary external source and one or more secondary external sources and determines when there is coincidence between the primary and one of the secondary sources is described. The instrument generates a finite time window (coincidence aperture) during which coincidence is defined to have occurred. The time intervals between coincidence apertures in which coincidences occur are measured.

  11. Geology Fulbrights

    NASA Astrophysics Data System (ADS)

    Fulbright grants in geology for 1988-89 remain open. Specific opportunities are available in Egypt, German Democratic Republic, Hungary, Iceland, Iraq, Kuwait, Morocco, Mozambique, Oman, Poland, Sudan, Syria, Tanzania, Turkey, U.S.S.R., West Bank, Yemen, and Zimbabwe. Other countries are also open to applications in any discipline, and geology is among their preferred fields.The grants are available until awarded and are open only to U.S. citizens. In Central and South America and French-speaking Africa, knowledge of host-country language is required. For more information, contact the Council for International Exchange of Scholars (CIES), 11 Dupont Circle N.W., Suite 300, Washington, DC 20036; tel. 202-939-5401.

  12. Geology team

    NASA Technical Reports Server (NTRS)

    1982-01-01

    Evaluating of the combined utility of narrowband and multispectral imaging in both the infrared and visible for the lithologic identification of geologic materials, and of the combined utility of multispectral imaging in the visible and infrared for lithologic mapping on a global bases are near term recommendations for future imaging capabilities. Long term recommendations include laboratory research into methods of field sampling and theoretical models of microscale mixing. The utility of improved spatial and spectral resolutions and radiometric sensitivity is also suggested for the long term. Geobotanical remote sensing research should be conducted to (1) separate geological and botanical spectral signatures in individual picture elements; (2) study geobotanical correlations that more fully simulate natural conditions; and use test sites designed to test specific geobotanical hypotheses.

  13. Determining the role of phonology in silent reading using event-related brain potentials.

    PubMed

    Newman, Randy Lynn; Connolly, John F

    2004-09-01

    The goal of the present study was to delineate phonology's role in silent reading using event-related brain potential (ERP) techniques. Terminal endings of high cloze sentences were manipulated in four conditions in which the terminal word was: (1) the high cloze ending and thus orthographically, phonologically and semantically congruent (e.g., The gambler had a streak of bad luck.); (2) a pseudohomophone that was orthographically incongruent, but was phonologically congruent to the anticipated ending (e.g., The ship disappeared into the thick phog [fog].); (3) a word that was orthographically, phonologically and semantically incongruent to expectations (e.g., The dog chased the cat up the Queen [tree].); or (4) a nonword and consequently orthographically, phonologically and semantically incongruent to expectations (e.g., The gas station is about two miles down the bole [road].). A N270 was elicited by orthographically incongruent words and nonwords (conditions 2, 3 and 4), likely reflecting violations of orthographic form expectations, while the presence of the N400 to semantically incongruent words and nonwords (conditions 3 and 4) reflected violations of semantic expectations. The relative absence of the N400 response to pseudohomophones (condition 3) indicates that integrating word meaning with sentential context is influenced by the phonological representation of the presented letter string. The implication of these results for theories of word recognition is discussed.

  14. Genetic Determinants of Target and Novelty Related Event-related Potentials in the Auditory Oddball Response

    PubMed Central

    Liu, Jingyu; Kiehl, Kent A.; Pearlson, Godfrey; Perrone-Bizzozero, Nora I.; Eichele, Tom; Calhoun, Vince D.

    2009-01-01

    Processing of novel and target stimuli in the auditory target detection or ‘oddball’ task encompasses the chronometry of perception, attention and working memory and is reflected in scalp recorded event-related potentials (ERPs). A variety of ERP components related to target and novelty processing have been described and extensively studied, and linked to deficits of cognitive processing. However, little is known about associations of genotypes with ERP endophenotypes. Here we sought to elucidate the genetic underpinnings of auditory oddball ERP components using a novel data analysis technique. A parallel independent component analysis of the electrophysiology and single nucleotide polymorphism (SNP) data was used to extract relations between patterns of ERP components and SNP associations purely based on an analysis incorporating higher order statistics. The method allows for broader associations of genotypes with phenotypes than traditional hypothesis-driven univariate correlational analyses. We show that target detection and processing of novel stimuli are both associated with a shared cluster of genes linked to the adrenergic and dopaminergic pathways. These results provide evidence of genetic influences on normal patterns of ERP generation during auditory target detection and novelty processing at the SNP association level. PMID:19285141

  15. Biomechanical events of swallowing are determined more by bolus consistency than by age or gender.

    PubMed

    van den Engel-Hoek, Lenie; de Groot, Imelda J M; Esser, Eva; Gorissen, Birthe; Hendriks, Jan C M; de Swart, Bert J M; Geurts, Alexander C H

    2012-05-15

    The biomechanics of swallowing saliva and substances of different consistencies were investigated in healthy children and adults. To this end, the duration and mean amplitude value (MAV) of surface electromyography (sEMG) of the submental muscle group (SMG) activity, the maximum anterior tongue pressure (ATP), and the rise and release slopes of ATP were measured while participants (39 female and 39 male participants, age 5-65 years) swallowed saliva, 5 mL water (reference), 5 mL thick liquid, and 5 mL solid food. Mean outcome parameters varied with the consistency of the liquid or food swallowed, with the exception of the rise slope of ATP. Moreover, outcome variables were not substantially affected by age with children of 5 years and older showing similar biomechanical events to those of adults. It is important to gain insight into the biomechanics of swallowing saliva and substances of different consistencies in order to understand the underlying mechanisms of dysphagia children and adults. Copyright © 2012 Elsevier Inc. All rights reserved.

  16. The frequency and duration of Salmonella-macrophage adhesion events determines infection efficiency.

    PubMed

    Achouri, Sarra; Wright, John A; Evans, Lewis; Macleod, Charlotte; Fraser, Gillian; Cicuta, Pietro; Bryant, Clare E

    2015-02-05

    Salmonella enterica causes a range of important diseases in humans and a in a variety of animal species. The ability of bacteria to adhere to, invade and survive within host cells plays an important role in the pathogenesis of Salmonella infections. In systemic salmonellosis, macrophages constitute a niche for the proliferation of bacteria within the host organism. Salmonella enterica serovar Typhimurium is flagellated and the frequency with which this bacterium collides with a cell is important for infection efficiency. We investigated how bacterial motility affects infection efficiency, using a combination of population-level macrophage infection experiments and direct imaging of single-cell infection events, comparing wild-type and motility mutants. Non-motile and aflagellate bacterial strains, in contrast to wild-type bacteria, collide less frequently with macrophages, are in contact with the cell for less time and infect less frequently. Run-biased Salmonella also collide less frequently with macrophages but maintain contact with macrophages for a longer period of time than wild-type strains and infect the cells more readily. Our results suggest that uptake of S. Typhimurium by macrophages is dependent upon the duration of contact time of the bacterium with the cell, in addition to the frequency with which the bacteria collide with the cell.

  17. Population as a proxy for infrastructure in the determination of event response and recovery resource allocations

    SciTech Connect

    Stamber, Kevin L.; Unis, Carl J.; Shirah, Donald N.; Gibson, Jessica A.; Fogleman, William E.; Kaplan, Paul

    2016-04-01

    Research into modeling of the quantification and prioritization of resources used in the recovery of lifeline critical infrastructure following disruptive incidents, such as hurricanes and earthquakes, has shown several factors to be important. Among these are population density and infrastructure density, event effects on infrastructure, and existence of an emergency response plan. The social sciences literature has a long history of correlating the population density and infrastructure density at a national scale, at a country-to-country level, mainly focused on transportation networks. This effort examines whether these correlations can be repeated at smaller geographic scales, for a variety of infrastructure types, so as to be able to use population data as a proxy for infrastructure data where infrastructure data is either incomplete or insufficiently granular. Using the best data available, this effort shows that strong correlations between infrastructure density for multiple types of infrastructure (e.g. miles of roads, hospital beds, miles of electric power transmission lines, and number of petroleum terminals) and population density do exist at known geographic boundaries (e.g. counties, service area boundaries) with exceptions that are explainable within the social sciences literature. Furthermore, the correlations identified provide a useful basis for ongoing research into the larger resource utilization problem.

  18. Population as a proxy for infrastructure in the determination of event response and recovery resource allocations

    DOE PAGES

    Stamber, Kevin L.; Unis, Carl J.; Shirah, Donald N.; ...

    2016-04-01

    Research into modeling of the quantification and prioritization of resources used in the recovery of lifeline critical infrastructure following disruptive incidents, such as hurricanes and earthquakes, has shown several factors to be important. Among these are population density and infrastructure density, event effects on infrastructure, and existence of an emergency response plan. The social sciences literature has a long history of correlating the population density and infrastructure density at a national scale, at a country-to-country level, mainly focused on transportation networks. This effort examines whether these correlations can be repeated at smaller geographic scales, for a variety of infrastructure types,more » so as to be able to use population data as a proxy for infrastructure data where infrastructure data is either incomplete or insufficiently granular. Using the best data available, this effort shows that strong correlations between infrastructure density for multiple types of infrastructure (e.g. miles of roads, hospital beds, miles of electric power transmission lines, and number of petroleum terminals) and population density do exist at known geographic boundaries (e.g. counties, service area boundaries) with exceptions that are explainable within the social sciences literature. Furthermore, the correlations identified provide a useful basis for ongoing research into the larger resource utilization problem.« less

  19. Direct determination of halogens in powdered geological and environmental samples using isotope dilution laser ablation ICP-MS

    NASA Astrophysics Data System (ADS)

    Boulyga, Sergei F.; Heumann, Klaus G.

    2005-04-01

    Laser ablation inductively coupled plasma isotope dilution mass spectrometry (LA-ICP-IDMS) with a special laser ablation system for bulk analyses (LINA-Spark(TM)-Atomiser) was applied for direct determinations of chlorine, bromine, and iodine in rock and sediment samples. Special attention was focused on possible inter-halogen fractionations and analyte/spike isotope fractionations by using LA-ICP-MS and LA-ICP-IDMS, respectively. A variation of Br/Cl and I/Cl element intensity ratios by a factor of 1.3-3 was observed when changing the nebulizer gas flow rate in the range of 0.84-1.0 L min-1 and the laser power density in the range of 2-10 GW cm-2, respectively. When using an internal standard for halogen quantification in LA-ICP-MS, this inter-element fractionation can cause systematic errors, which can be avoided by applying the isotope dilution technique. However, at high laser power densities (>5.7 GW cm-2 for iodine and >4.0 GW cm-2 for bromine and chlorine) the corresponding measured isotope ratio of the isotope-diluted sample deviates significantly from the target value. Under optimised conditions concentrations in the range of 30 [mu]g g-1-16 × 103 [mu]g g-1 for chlorine, <2-140 [mu]g g-1 for bromine, and <0.1-31 [mu]g g-1 for iodine were determined by LA-ICP-IDMS in two sediment reference materials (SRM 1646, SRM 2704) and three rock reference samples (GS-N, Granite; BX-N, Bauxite; DT-N, Disthene), which have not been certified for these halogens. The sediment results agree well within the given uncertainties with indicative values by different methods and the results of the rock samples with those obtained by negative thermal ionisation isotope dilution mass spectrometry. The detection limits of LA-ICP-IDMS are 8 [mu]g g-1 for chlorine, 1.7 [mu]g g-1 for bromine, and 0.1 [mu]g g-1 for iodine.

  20. Boron isotope determinations in waters and other geological materials: analytical techniques and inter-calibration of measurements.

    PubMed

    Tonarini, Sonia; Pennisi, Maddalena; Gonfiantini, Roberto

    2009-06-01

    The (11)B/(10)B ratio exhibits wide variations in nature; thus, boron isotopes have found numerous applications in geochemistry, hydrology, and environmental studies. The main analytical techniques used are as follows: positive thermal ionisation mass spectrometry is the most precise (about 0.2 per thousand of the boron isotope ratio), but requires complex and laborious sample preparation; negative thermal ionisation mass spectrometry is less precise (about 0.5 per thousand), but rapid and suitable for water samples, whereas total evaporation-NTIMS allows for identification of the precise boron isotope composition of marine carbonates. It is expected that multi-collection system inductively coupled plasma mass spectrometry (MC-ICPMS) will eventually combine high precision with simple analytical procedures. Secondary ion mass spectrometry and laser ablation (LA)-MC-ICPMS allow in situ determinations on solid samples, but require the availability of calibration materials which are chemically and mineralogically similar to samples. These features of boron isotope measurement techniques were confirmed by the results of the first inter-laboratory comparison of measurements, organised by the Istituto di Geoscienze e Georisorse in Pisa. Finally, two examples of boron isotope applications in groundwater investigations are reported.

  1. Three-dimensional geologic modeling to determine the spatial attributes of hydrocarbon contamination, Noval Facility Fuel Farm, El Centro, California

    SciTech Connect

    Johnson, C.; Mutch, S.; Padgett, D.; Roche, L. )

    1994-04-01

    An investigation was conducted at the Naval Air Facility located in El Centro (NAFEC), to determine the vertical and horizontal extent of hydrocarbon contamination at the facilities fuel farm. The fuel products are the result of tank and pipeline leakage, past tank cleaning, and past disposal of fuel dispensing and filter cleaning practices. Subsurface soil and groundwater data was collected via soil borings, monitoring wells, and CPT probes. Soil, groundwater, and analytical data were integrated using the LYNX geoscience modeling system (GMS). Interactive sessions with the data visualizer helped guide the modeling and identify data gaps. Modeling results indicate a continuous surface confining clay layer to a depth of about 12 to 15 ft. Groundwater is confined beneath this clay layer and monitoring wells indicate about 3 to 5 ft of artesian head. Hydrocarbon contamination is concentrated within this clay layer from about 5 to 12 ft below the ground surface. Residual fuel products located in the groundwater are attributed to slow leakage through the confirming clay layer. LYNX was also used to compute volumes of contaminated soil to aid in remediation cost analysis. Preliminary figures indicate about 60,000 yards[sup 3] of contaminated soil. Since the contamination is primarily confined to relatively impermeable clayey soils, site remediation will likely be ex-situ land farming.

  2. Guidelines for sample collecting and analytical methods used in the U.S. Geological Survey for determining chemical composition of coal

    USGS Publications Warehouse

    Swanson, Vernon Emanuel; Huffman, Claude

    1976-01-01

    This report is intended to meet the many requests for information on current U.S. Geological Survey procedures in handling coal samples. In general, the exact type and number of samples of coal and associated rock to be collected are left to the best judgment of the geologist. Samples should be of unweathered coal or rock and representative of the bed or beds sampled; it is recommended that two channel samples, separated by 10 to 100 yards (10 to 100 metres) and weighing 4 to 5 pounds ( 1.8 to 2.3 kilograms) each, be collected of each 5 feet ( 1.5 metres) of vertical section. Care must be taken to avoid any sample contamination, and to record the exact locality, thickness, and stratigraphic information for each sample. Analytical methods are described for the determination of major, minor, and trace elements in coal. Hg, As, Sb, F, Se, U, and Th are determined in the raw coal, and the following 34 elements are determined after ashing the coal: Si, Al, Ca, Mg, Na, K, Fe (total), Cl, Ti, Mn, P, S (total), Cd, Li, Cu, Zn, Pb, B, Ba, Be, Co, Cr, Ga, La, Mo, Nb, Ni, Sc, Sr, Ti, V, Y, Yb, and Zr. The methods used to determine these elements include atomic absorption spectroscopy, X-ray fluorescence spectroscopy, optical emission spectroscopy, spectrophotometry, selective-ion electrode, and neutron activation analysis. A split of representative coal samples is submitted to the U.S. Bureau of Mines for proximate, ultimate, forms of sulfur, and Btu determinations.

  3. Spectroscopic determination of thermal impulse in sub-second heating events using lanthanide-doped oxide precursors and phenomenological modeling

    SciTech Connect

    Anderson, Benjamin R. Gunawidjaja, Ray; Price, Patrick; Eilers, Hergen

    2016-08-28

    Using a mixture of crystalline-Ho:ZrO{sub 2}, precursor-Dy:Y{sub 2}O{sub 3}, and precursor-Eu:ZrO{sub 2} nanoparticles we develop thermal impulse sensors capable of measuring equivalent isothermal temperatures and durations during a heating event, with response times of <100 ms, and a temperature range of at least 673 K to 1173 K. In order to determine the temperature and duration from the sensors after the heating event we measure the sensors' fluorescence spectrum, which is then compared with lab based calibration data. By using two precursor materials with different reaction kinetics we are able to extract both temperature and duration. Based on blind sample testing we find that the sensors and calculation method are accurate for measuring temperature and duration, but currently suffer a lack of precision due to difficulties in producing homogeneously heated samples.

  4. Determination of rare earth elements, uranium and thorium in geological samples by ICP-MS, using an automatic fusion machine as an alkaline digestion tool.

    NASA Astrophysics Data System (ADS)

    Granda, Luis; Rivera, Maria; Velasquez, Colon; Barona, Diego; Carpintero, Natalia

    2014-05-01

    At the present time, rare earth elements deposits have became in strategic resources for extraction of raw materials in order to manufacture high tech devices (computers, LCD, cell phones, batteries for hybrid vehicles, fiber optics and wind turbines) (1).The appropriate analytical determination of the REE ( rare earth elements) in sediment and rock samples , is important to find potential deposits and to recognize geological environments for identifying possible alterations and mineral occurrences. The alkaline fusion, which aim is to move the entire sample from solid to liquid state by forming water soluble complexes of boron and lithium, as a previous procedure for the determination of these elements, usually takes a lot of time due to the complexity of the analysis phase and by the addition of other reagents (Tm and HF ) (2) to compensate the lack of strict temperature control. The objective of this work is to develop an efficient alternative to alkaline digestion using an electrical fusion machine, which allows to create temperature programs with advanced process control and supports up to 5 samples simultaneously, which generates a reproducibility of the method and results during the melting step. Additionally, this new method permits the processing of a larger number of samples in a shorter time. The samples analyzed in this method were weighed into porcelain crucibles and subjected to calcination for 4 hours at 950 ° C in order to determine the Lost on Ignition (LOI ) , that serves to adjust the analytical results and to preserve the shelf life of the platinum ware. Subsequently, a fraction of the calcined sample was weighed into platinum crucibles and mixed with ultra-pure lithium metaborate ( flux ) 1:4 . The crucible was then placed in the fusion machine, which was programmed to take the sample from room temperature to 950 ° C in five minutes, make a small ramp to 970 ° C maintain that temperature for five minutes and download the melt in a 10 % v / v

  5. Determination of Fluorine in Fourteen Microanalytical Geologic Reference Materials using SIMS, EPMA, and Proton Induced Gamma Ray Emission (PIGE) Analysis

    NASA Astrophysics Data System (ADS)

    Guggino, S. N.; Hervig, R. L.

    2010-12-01

    Fluorine (F) is a volatile constituent of magmas and hydrous minerals, and trace amounts of F are incorporated into nominally anhydrous minerals such as olivine and clinopyroxene. Microanalytical techniques are routinely used to measure trace amounts of F at both high sensitivity and high spatial resolution in glasses and crystals. However, there are few well-established F concentrations for the glass standards routinely used in microanalytical laboratories, particularly standards of low silica, basaltic composition. In this study, we determined the F content of fourteen commonly used microanalytical glass standards of basaltic, intermediate, and rhyolitic composition. To serve as calibration standards, five basaltic glasses with ~0.2 to 2.5 wt% F were synthesized and characterized. A natural tholeiite from the East Pacific Rise was mixed with variable amounts of CaF2. The mixture was heated in a 1 atmosphere furnace to 1440 °C at fO2 = NNO for 30 minutes and quenched in water. Portions of the run products were studied by electron probe microanalysis (EPMA) and secondary ion mass spectrometry (SIMS). The EPMA used a 15 µm diameter defocused electron beam with a 15 kV accelerating voltage and a 25 nA primary current, a TAP crystal for detecting FKα X-rays, and Biotite 3 as the F standard. The F contents by EPMA agreed with the F added to the basalts after correction for mass loss during melting. The SIMS analyses used a primary beam of 16O- and detection of low-energy negative ions (-5 kV) at a mass resolution that resolved 18OH. Both microanalytical techniques confirmed homogeneity, and the SIMS calibration defined by EPMA shows an excellent linear trend with backgrounds of 2 ppm or less. Analyses of basaltic glass standards based on our synthesized calibration standards gave the following F contents and 2σ errors (ppm): ALV-519 = 83 ± 3; BCR-2G = 359 ± 6; BHVO-2G = 322 ± 15; GSA-1G = 10 ± 1; GSC-1G = 11 ± 1; GSD-1G = 19 ± 2; GSE-1G = 173 ± 1; KL2G (MPI

  6. The siting record: An account of the programs of federal agencies and events that have led to the selection of a potential site for a geologic respository for high-level radioactive waste

    SciTech Connect

    Lomenick, T.F.

    1996-03-01

    This record of siting a geologic repository for high-level radioactive wastes (HLW) and spent fuel describes the many investigations that culminated on December 22, 1987 in the designation of Yucca Mountain (YM), as the site to undergo detailed geologic characterization. It recounts the important issues and events that have been instrumental in shaping the course of siting over the last three and one half decades. In this long task, which was initiated in 1954, more than 60 regions, areas, or sites involving nine different rock types have been investigated. This effort became sharply focused in 1983 with the identification of nine potentially suitable sites for the first repository. From these nine sites, five were subsequently nominated by the U.S. Department of Energy (DOE) as suitable for characterization and then, in 1986, as required by the Nuclear Waste Policy Act of 1982 (NWPA), three of these five were recommended to the President as candidates for site characterization. President Reagan approved the recommendation on May 28, 1986. DOE was preparing site characterization plans for the three candidate sites, namely Deaf Smith County, Texas; Hanford Site, Washington; and YM. As a consequence of the 1987 Amendment to the NWPA, only the latter was authorized to undergo detailed characterization. A final Site Characterization Plan for Yucca Mountain was published in 1988. Prior to 1954, there was no program for the siting of disposal facilities for high-level waste (HLW). In the 1940s and 1950s, the volume of waste, which was small and which resulted entirely from military weapons and research programs, was stored as a liquid in large steel tanks buried at geographically remote government installations principally in Washington and Tennessee.

  7. Carbonate "Clumped" Isotope Determination of Seawater Temperature During the End-Triassic Extinction Event

    NASA Astrophysics Data System (ADS)

    Gammariello, R. T., Jr.; Petryshyn, V. A.; Ibarra, Y.; Greene, S. E.; Corsetti, F. A.; Bottjer, D. J.; Tripati, A.

    2014-12-01

    Stromatolites are laminated sedimentary structures that are commonly thought to be created by cyanobacteria, either through the trapping and binding of sediment, or through metabolically-induced precipitation. However, stromatolite formation is poorly understood. In general, stromatolite abundance was higher in the Proterozoic than the Phanerozoic, but notable increases in stromatolite abundance occur in association with Phanerozoic mass extinction events. Here, we focus on stromatolites from the latest Triassic Cotham Marble (United Kingdom) that are associated with the extinction interval. The end-Triassic mass extinction is coincident with large-scale volcanism in the Central Atlantic Magmatic Province (CAMP) and the associated breakup of Pangea. Some hypothesize that CAMP-associated increases in atmospheric CO2 led to a rise in global temperatures and ocean acidification that caused or enhanced the extinction. In order to quantify the role of climate change with respect to the end-Triassic mass extinction, we applied the carbonate "clumped" isotope paleothermometer to the well-preserved Cotham Marble stromatolites. The stromatolites were deposited in the shallow Tethys Sea, and today occur in several localities across the southwestern UK. The stromatolites alternate on the cm scale between laminated and dendrolitic microstructures and each was microdrilled for clumped isotope analysis. The two microstructures display different temperatures of formation, where the dendrolitic portions apparently grew under cooler conditions than laminated layers, and younger layers grew in cooler conditions than older layers. Our results suggest that temperature fluctuated and potentially trended towards amelioration of the warm temperatures during the deposition of the Cotham Marble.

  8. Two Cenozoic tectonic events of N-S and E-W extension in the Lhasa Terrane: Evidence from geology and geochronology

    NASA Astrophysics Data System (ADS)

    Huang, Feng; Xu, Ji-Feng; Chen, Jian-Lin; Wu, Jian-Bin; Zeng, Yun-Chuan; Xiong, Qiu-Wei; Chen, Xue-Feng; Yu, Hong-Xia

    2016-02-01

    Cenozoic active structures in the Tibetan Plateau are mainly regional N-S trending extensional faults and grabens, and E-W trending extensional tracks that are related to the transition from syn- to post-collision between India and Asia. E-W trending tracks are parallel to the direction of Neo-Tethyan oceanic convergence and consist of extensional volcanic-sedimentary basins and magmatic dykes in the southern Lhasa Terrane, Tibet. N-S trending tracks comprise faults and grabens, which are widely developed in Tibet. It remains unknown how and when the geodynamic transition from E-W to N-S trending tectonic tracks occurred. This study describes both E-W and N-S trending tectonic tracks identified at Dazi area of southern Lhasa Terrane, where E-W trending mafic dykes intruded a granitoid and late-stage N-S trending felsic dykes cut across E-W trending mafic dykes. Zircons from four granitoid samples yield consistent crystallization ages of ca. 60 Ma and positive εHf(t) values (~+ 9). An altered dioritic vein, which cuts the mafic dykes, yields an age of ca. 53 Ma. These new dating results indicate that E-W trending dykes, which formed due to regional N-S extension, were emplaced between 60 and 53 Ma. In addition, two N-S trending monzonitic porphyritic dykes, which cut the mafic dykes, yield U-Pb zircon ages of ca. 17 Ma with moderate positive εHf(t) values (+ 3 to + 9.6), as well as a NNE-SSW trending quartz monzonitic dyke, which cuts all other types of dykes, yields U-Pb ages of ca. 13 Ma. This suggests that E-W extension took place between 17 and 13 Ma. These results, in combination with existing age data for Gangdese granitoids and mafic magmatism, indicate the occurrence of two major extensional events at 60-53 Ma and 17-13 Ma. In turn, this implies that the transition from E-W to N-S trending tectonic and the onset of E-W extension occurred at ca. 17 Ma or slightly earlier. Paleocene granitoids have geochemical characteristics that are indicative of both

  9. Determination of Barium and selected rare-earth elements in geological materials employing a HpGe detector by radioisotope excited x-ray fluorescence

    SciTech Connect

    LaBrecque, J.J.; Preiss, I.L.

    1984-01-01

    The laterite material (geological) from Cerro Impacto was first studied by air radiometric techniques in the 1970's and was found to have an abnormally high radioactive background. Further studies showed this deposit to be rich in thorium, columbium, barium and rare-earth elements (mostly La, Ce, Pr and Nd). A similar work has been reported for the analysis of Brazil's lateritic material from Morro do Ferro to determine elemental compositions (including barium and rare-earth elements) and its relationship to the mobilization of thorium from the deposit using a Co-57 radioisotope source. The objective of this work was to develop an analytical method to determine barium and rare-earth element present in Venezuelan lateritic material from Cerro Impacto. We have employed a method before, employing a Si(Li) detector, but due to the low detection efficiencies in the rare-earth K-lines region (about 30 KeV - 40 KeV), we have decided to study the improvement in sensitivities and detection limits using an hyperpure germanium detector.

  10. MGR External Events Hazards Analysis

    SciTech Connect

    L. Booth

    1999-11-06

    The purpose and objective of this analysis is to apply an external events Hazards Analysis (HA) to the License Application Design Selection Enhanced Design Alternative 11 [(LADS EDA II design (Reference 8.32))]. The output of the HA is called a Hazards List (HL). This analysis supersedes the external hazards portion of Rev. 00 of the PHA (Reference 8.1). The PHA for internal events will also be updated to the LADS EDA II design but under a separate analysis. Like the PHA methodology, the HA methodology provides a systematic method to identify potential hazards during the 100-year Monitored Geologic Repository (MGR) operating period updated to reflect the EDA II design. The resulting events on the HL are candidates that may have potential radiological consequences as determined during Design Basis Events (DBEs) analyses. Therefore, the HL that results from this analysis will undergo further screening and analysis based on the criteria that apply during the performance of DBE analyses.

  11. Ischemic event characteristics determine the extent of myocardial stunning in conscious dogs.

    PubMed

    Wouters, P F; Van de Velde, M; Van Aken, H; Flameng, W

    1996-01-01

    Both the severity and duration of postischemic myocardial dysfunction ("stunned" myocardium) are unpredictable and may vary considerably between subjects that underwent apparently similar ischemic insults. To explain this heterogeneous response of the heart to ischemia and reperfusion, we investigated the determinants of stunning in conscious dogs. Twenty-five dogs were chronically instrumented for measurement of global and regional myocardial performance (wall thickening) and myocardial perfusion (coloured microspheres). A hydraulic occluder was positioned around the LAD coronary artery. Conscious dogs were subjected to acute coronary artery occlusions of predetermined duration (2, 5 and 10 min), followed by complete reperfusion. Multiple regression analysis identified the following variables as determinants of postischemic contractile recovery: 1) the duration of ischemia (p < 0.01),2) the amount of collateral perfusion (p = 0.01) and 3) left ventricular end-diastolic pressure during ischemia (p < 0.01). Neither the severity of regional dyskinesia during ischemia nor indices of global systolic hemodynamic performance correlated with the rate of recovery. Our data confirm that myocardial stunning relates primarily to the intensity of preceding ischemia. Variations in the preexisting level of collateral perfusion may result in markedly different recovery profiles. Except for LV end-diastolic pressure during ischemia, indices of global and regional cardiac performance fail to predict the severity of postischemic contractile failure.

  12. Experimental determination of single-event upset (SEU) as a function of collected charge in bipolar integrated circuits

    NASA Technical Reports Server (NTRS)

    Zoutendyk, J. A.; Malone, C. J.; Smith, L. S.

    1984-01-01

    Single-Event Upset (SEU) in bipolar integrated circuits (ICs) is caused by charge collection from ion tracks in various regions of a bipolar transistor. This paper presents experimental data which have been obtained wherein the range-energy characteristics of heavy ions (Br) have been utilized to determine the cross section for soft-error generation as a function of charge collected from single-particle tracks which penetrate a bipolar static RAM. The results of this work provide a basis for the experimental verification of circuit-simulation SEU modeling in bipolar ICs.

  13. Discrimination Analysis of Earthquakes and Man-Made Events Using ARMA Coefficients Determination by Artificial Neural Networks

    SciTech Connect

    AllamehZadeh, Mostafa

    2011-12-15

    A Quadratic Neural Networks (QNNs) model has been developed for identifying seismic source classification problem at regional distances using ARMA coefficients determination by Artificial Neural Networks (ANNs). We have devised a supervised neural system to discriminate between earthquakes and chemical explosions with filter coefficients obtained by windowed P-wave phase spectra (15 s). First, we preprocess the recording's signals to cancel out instrumental and attenuation site effects and obtain a compact representation of seismic records. Second, we use a QNNs system to obtain ARMA coefficients for feature extraction in the discrimination problem. The derived coefficients are then applied to the neural system to train and classification. In this study, we explore the possibility of using single station three-component (3C) covariance matrix traces from a priori-known explosion sites (learning) for automatically recognizing subsequent explosions from the same site. The results have shown that this feature extraction gives the best classifier for seismic signals and performs significantly better than other classification methods. The events have been tested, which include 36 chemical explosions at the Semipalatinsk test site in Kazakhstan and 61 earthquakes (mb = 5.0-6.5) recorded by the Iranian National Seismic Network (INSN). The 100% correct decisions were obtained between site explosions and some of non-site events. The above approach to event discrimination is very flexible as we can combine several 3C stations.

  14. RETRIEVAL EVENTS EVALUATION

    SciTech Connect

    T. Wilson

    1999-11-12

    The purpose of this analysis is to evaluate impacts to the retrieval concept presented in the Design Analysis ''Retrieval Equipment and Strategy'' (Reference 6), from abnormal events based on Design Basis Events (DBE) and Beyond Design Basis Events (BDBE) as defined in two recent analyses: (1) DBE/Scenario Analysis for Preclosure Repository Subsurface Facilities (Reference 4); and (2) Preliminary Preclosure Design Basis Event Calculations for the Monitored Geologic Repository (Reference 5) The objective of this task is to determine what impacts the DBEs and BDBEs have on the equipment developed for retrieval. The analysis lists potential impacts and recommends changes to be analyzed in subsequent design analyses for developed equipment, or recommend where additional equipment may be needed, to allow retrieval to be performed in all DBE or BDBE situations. This analysis supports License Application design and therefore complies with the requirements of Systems Description Document input criteria comparison as presented in Section 7, Conclusions. In addition, the analysis discusses the impacts associated with not using concrete inverts in the emplacement drifts. The ''Retrieval Equipment and Strategy'' analysis was based on a concrete invert configuration in the emplacement drift. The scope of the analysis, as presented in ''Development Plan for Retrieval Events Evaluation'' (Reference 3) includes evaluation and criteria of the following: Impacts to retrieval from the emplacement drift based on DBE/BDBEs, and changes to the invert configuration for the preclosure period. Impacts to retrieval from the main drifts based on DBE/BDBEs for the preclosure period.

  15. Mineralogy and geochemistry of claystones from the Guadalupian-Lopingian boundary at Penglaitan, South China: Insights into the pre-Lopingian geological events

    NASA Astrophysics Data System (ADS)

    Zhong, Yu-Ting; He, Bin; Xu, Yi-Gang

    2013-01-01

    The Guadalupian-Lopingian (G/L) boundary, at a stratigraphically well-documented outcrop in Penglaitan, Guangxi Autonomous Region, South China, has been approved as the Global Stratotype Section and Point (GSSP). Several volcanic ashes or tuffs occur at this boundary, but their mineralogy and geochemistry are not available yet and no reliable age for this boundary has been obtained. A combined study of mineralogy, geochemistry and geochronology has been carried out in this study on six layers of claystones collected below (Group 1) and above (Group 2) the G/L boundary at the Penglaitan section. Both Group 1 and Group 2 claystones are likely clastic in origin, rather than volcanic ashes as previously thought. Thus the Penglaitan claystones are not suitable for age determination of the G/L boundary. They are significantly different in terms of mineralogy and geochemistry. Specifically, Group 1 claystones are likely derived from a mafic source which is genetically related to the Emeishan large igneous province, therefore providing additional evidence for the synchroneity between the G/L boundary mass extinction and the Emeishan volcanism. Group 2 samples were derived from a felsic source, of which zircons yield an age spectrum peaked at 262 ± 3 Ma, undistinguishable within the uncertainty from the currently accepted G/L boundary age (260.4 ± 0.4 Ma). Nevertheless, Group 2 samples are not related to Emeishan volcanism, because their negative zircon ɛHf(t) values differ significantly from those of Emeishan magmas and trace element compositions of zircons are indicative of an arc source, rather than a within-plate source. In consideration of paleogeographic reconstruction, we propose that the Group 2 claystones may have been derived from continental arcs during the palaeo-Tethys evolution. This is the first sedimentary evidence for Permian continental arc in the northern margin of palaeo-Tethys.

  16. Using Student-Created Metaphors to Comprehend Geologic Time.

    ERIC Educational Resources Information Center

    Ritger, Scott David; Cummins, Robert Hays

    1991-01-01

    Presents an activity for introducing students to geologic time. Students choose their own metaphor for geologic time, selecting milestones in Earth history and scaling these events to their metaphors.(PR)

  17. Using Student-Created Metaphors to Comprehend Geologic Time.

    ERIC Educational Resources Information Center

    Ritger, Scott David; Cummins, Robert Hays

    1991-01-01

    Presents an activity for introducing students to geologic time. Students choose their own metaphor for geologic time, selecting milestones in Earth history and scaling these events to their metaphors.(PR)

  18. Results from exploratory drill hole UE2ce, Northwest Yucca Flat, Nevada Test Site, near the NASH Event

    SciTech Connect

    Pawloski, G.A.

    1982-03-03

    Exploratory drill hole UE2ce was drilled in January 1977 to determine geologic and geophysical characteristics of this site. This report presents geophysical logs, lithology, geologic structure, water table measurements, and physical properties for this drill hole. The data are then extrapolated to the NASH site, an event in U2ce, 55.6 m due north of UE2ce.

  19. A fast and robust method for moment tensor and depth determination of shallow seismic events in CTBT related studies.

    NASA Astrophysics Data System (ADS)

    Baker, Ben; Stachnik, Joshua; Rozhkov, Mikhail

    2017-04-01

    International Data Center is required to conduct expert technical analysis and special studies to improve event parameters and assist State Parties in identifying the source of specific event according to the protocol to the Protocol to the Comprehensive Nuclear Test Ban Treaty. Determination of seismic event source mechanism and its depth is closely related to these tasks. It is typically done through a strategic linearized inversion of the waveforms for a complete or subset of source parameters, or similarly defined grid search through precomputed Greens Functions created for particular source models. In this presentation we demonstrate preliminary results obtained with the latter approach from an improved software design. In this development we tried to be compliant with different modes of CTBT monitoring regime and cover wide range of source-receiver distances (regional to teleseismic), resolve shallow source depths, provide full moment tensor solution based on body and surface waves recordings, be fast to satisfy both on-demand studies and automatic processing and properly incorporate observed waveforms and any uncertainties a priori as well as accurately estimate posteriori uncertainties. Posterior distributions of moment tensor parameters show narrow peaks where a significant number of reliable surface wave observations are available. For earthquake examples, fault orientation (strike, dip, and rake) posterior distributions also provide results consistent with published catalogues. Inclusion of observations on horizontal components will provide further constraints. In addition, the calculation of teleseismic P wave Green's Functions are improved through prior analysis to determine an appropriate attenuation parameter for each source-receiver path. Implemented HDF5 based Green's Functions pre-packaging allows much greater flexibility in utilizing different software packages and methods for computation. Further additions will have the rapid use of Instaseis

  20. The costs associated with adverse event procedures for an international HIV clinical trial determined by activity-based costing.

    PubMed

    Chou, Victoria B; Omer, Saad B; Hussain, Hamidah; Mugasha, Christine; Musisi, Maria; Mmiro, Francis; Musoke, Philippa; Jackson, J Brooks; Guay, Laura A

    2007-12-01

    To determine costs for adverse event (AE) procedures for a large HIV perinatal trial by analyzing actual resource consumption using activity-based costing (ABC) in an international research setting. The AE system for an ongoing clinical trial in Uganda was evaluated using ABC techniques to determine costs from the perspective of the study. Resources were organized into cost categories (eg, personnel, patient care expenses, laboratory testing, equipment). Cost drivers were quantified, and unit cost per AE was calculated. A subset of time and motion studies was performed prospectively to observe clinic personnel time required for AE identification. In 18 months, there were 9028 AEs, with 970 (11%) reported as serious adverse events. Unit cost per AE was $101.97. Overall, AE-related costs represented 32% ($920,581 of $2,834,692) of all study expenses. Personnel ($79.30) and patient care ($11.96) contributed the greatest proportion of component costs. Reported AEs were predominantly nonserious (mild or moderate severity) and unrelated to study drug(s) delivery. Intensive identification and management of AEs to conduct clinical trials ethically and protect human subjects require expenditure of substantial human and financial resources. Better understanding of these resource requirements should improve planning and funding of international HIV-related clinical trials.

  1. Confirmation of the Planetary Microlensing Signal and Star and Planet Mass Determinations for Event OGLE-2005-BLG-169

    NASA Astrophysics Data System (ADS)

    Bennett, D. P.; Bhattacharya, A.; Anderson, J.; Bond, I. A.; Anderson, N.; Barry, R.; Batista, V.; Beaulieu, J.-P.; DePoy, D. L.; Dong, Subo; Gaudi, B. S.; Gilbert, E.; Gould, A.; Pfeifle, R.; Pogge, R. W.; Suzuki, D.; Terry, S.; Udalski, A.

    2015-08-01

    We present Hubble Space Telescope (HST) Wide Field Camera 3 (WFC3) observations of the source and lens stars for planetary microlensing event OGLE-2005-BLG-169, which confirm the relative proper motion prediction due to the planetary light curve signal observed for this event. This (and the companion Keck result) provide the first confirmation of a planetary microlensing signal, for which the deviation was only 2%. The follow-up observations determine the flux of the planetary host star in multiple passbands and remove light curve model ambiguity caused by sparse sampling of part of the light curve. This leads to a precise determination of the properties of the OGLE-2005-BLG-169Lb planetary system. Combining the constraints from the microlensing light curve with the photometry and astrometry of the HST/WFC3 data, we find star and planet masses of {M}*=0.69+/- 0.02{M}⊙ and {m}{{p}}=14.1+/- 0.9{M}\\oplus . The planetary microlens system is located toward the Galactic bulge at a distance of {D}L=4.1+/- 0.4 kpc and the projected star-planet separation is {a}\\perp =3.5+/- 0.3 AU, corresponding to a semimajor axis of a={4.0}-0.6+2.2 AU.

  2. Effective damage zone volume of fault zones and initial salinity distribution determine intensity of shallow aquifer salinization in geological underground utilization

    NASA Astrophysics Data System (ADS)

    Langer, M.; Tillner, E.; Kempka, T.; Kühn, M.

    2015-06-01

    Injection of fluids into deep saline aquifers causes a pore pressure increase in the storage formation, and thus displacement of resident brines. Via hydraulically conductive faults, brine may migrate upwards into shallower aquifers, and lead to unwanted salinization of potable groundwater resources. In the present study, we investigated different scenarios for a prospective storage site close to the city of Beeskow in the Northeast German Basin by using a 3-D regional scale model (100 km × 100 km × 1.34 km) that includes four ambient fault zones. The focus was on assessing the impact of fault length and the effect of an overlying secondary reservoir as well as model boundary conditions on the potential salinization of shallow groundwater resources. We employed numerical simulations of brine injection as a representative fluid using the simulator TOUGH2-MP. Our simulation results demonstrate that pressure build-up within the reservoir determines the intensity and duration of fluid flow through the faults, and hence salinization of shallower aquifers. Application of different boundary conditions proved that these have a crucial impact on reservoir fluid displacement. If reservoir boundaries are closed, the fluid migrated upwards into the shallow aquifer, corresponds to the overall injected fluid mass. In that case, a short hydraulically conductive fault length and the presence of an overlying secondary reservoir leads only to retardation in brine displacement up to a factor of five and three, respectively. If the reservoir boundaries are open, salinization is considerably reduced: in the presence of a secondary reservoir, 33% of equivalent brine mass migrates into the shallow aquifer, if all four faults are hydraulically open over their entire length, whereas the displaced equivalent brine mass is only 12% for a single fault of two kilometres length. Taking into account the considered geological boundary conditions, the brine originates in maximum from the upper 4

  3. Determination of source parameters and full moment tensors of seismic events in a very heterogeneous mining environment

    NASA Astrophysics Data System (ADS)

    Vavrycuk, V.; Kuehn, D.

    2012-04-01

    Using seismic data from 5 blasts and 5 induced events recorded in the Pyhasalmi ore mine, Finland, we propose and test a strategy for the inversion of moment tensors from waveforms in a very heterogeneous mining environment. The heterogeneities are caused not only by presence of the ore body in the host rock, but especially by presence of a system of tunnels and by large excavation areas in the mines. We show that the moment tensor inversion is feasible even in such a complex velocity model. First, locations of events needed in the inversion can be determined using the eikonal solver, provided a detailed geometry of the tunnels and the cavities is well documented and the velocities of rocks are known with a good accuracy. The solver takes into account refractions and diffractions and it is applicable even in strongly heterogeneous media where ray tracing may be problematic. Second, the Green's functions needed for the waveform moment tensor inversion can be calculated by the full waveform modelling capable to reproduce complex interactions of waves with the structure. We use the 3-D finite difference viscoelastic code and run it on a model specified using the spatial grid of 2 m and with the sampling frequency of 10 kHz. The computational time is reduced using the reciprocity principle. Third, the moment tensor inversion is performed in the time domain using the generalized linear inversion. Compared to the computation of the Green's functions, the inversion is computationally undemanding. To suppress the sensitivity of the inversion to inaccuracies in the locations and in the velocity model, we analyse data in the frequency range from 30 to 80 Hz. The analysis of 5 blasts and 5 induced microseismic events proved that the moment tensor inversion was successful. As expected the blasts display high percentage of the positive ISO components attaining values from 60 to 80%. However, we cannot exclude that some minor shear faulting was triggered during the blasting. On

  4. Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory; determination of selected carbamate pesticides in water by high-performance liquid chromatography

    USGS Publications Warehouse

    Werner, S.L.; Johnson, S.M.

    1994-01-01

    As part of its primary responsibility concerning water as a national resource, the U.S. Geological Survey collects and analyzes samples of ground water and surface water to determine water quality. This report describes the method used since June 1987 to determine selected total-recoverable carbamate pesticides present in water samples. High- performance liquid chromatography is used to separate N-methyl carbamates, N-methyl carbamoyloximes, and an N-phenyl carbamate which have been extracted from water and concentrated in dichloromethane. Analytes, surrogate compounds, and reference compounds are eluted from the analytical column within 25 minutes. Two modes of analyte detection are used: (1) a photodiode-array detector measures and records ultraviolet-absorbance profiles, and (2) a fluorescence detector measures and records fluorescence from an analyte derivative produced when analyte hydrolysis is combined with chemical derivatization. Analytes are identified and confirmed in a three-stage process by use of chromatographic retention time, ultraviolet (UV) spectral comparison, and derivatization/fluorescence detection. Quantitative results are based on the integration of single-wavelength UV-absorbance chromatograms and on comparison with calibration curves derived from external analyte standards that are run with samples as part of an instrumental analytical sequence. Estimated method detection limits vary for each analyte, depending on the sample matrix conditions, and range from 0.5 microgram per liter to as low as 0.01 microgram per liter. Reporting levels for all analytes have been set at 0.5 microgram per liter for this method. Corrections on the basis of percentage recoveries of analytes spiked into distilled water are not applied to values calculated for analyte concentration in samples. These values for analyte concentrations instead indicate the quantities recovered by the method from a particular sample matrix.

  5. Stable water isotopes and Rn-222 to determine dam and groundwater contribution to baseflow and event flow in a small agricultural catchment

    NASA Astrophysics Data System (ADS)

    Hughes, C. E.; Scarff, S. A.; Morrison, T.; Fischer, M. J.; Adams, G. A.; Hart, M. R.

    2009-04-01

    In order to improve local water managers understanding of nutrient inputs into Sydney's drinking water catchments, a detailed study of nutrients in streamflow has been carried out in the headwaters of Kellys Ck in the New South Wales southern highlands, Australia. One component of this study attempted to determine the flow pathways contributing to baseflow and to runoff generation during a rainfall event over a 128 ha catchment area. Rainfall, stream, shallow groundwater, spring and dam samples were collected during baseflow (pre-event), flow event and post event periods around a 4 day rainfall event in July 2008. Samples were analysed for stable water isotopes, Rn-222, DOC, nutrients and major ions. Hydrograph separation and transit time distribution modelling were used to examine the contribution of event water, dam water and pre-event water to streamflow for a 9 day period encompassing the rain event. The results show that pre-event and event water contribute equally to streamflow with the pre-event contribution dominated by evaporated water (pre-event dam storage and soil water) rather than the more depleted shallow groundwater and spring water. Rn-222 was also used to understand the spatial variation of groundwater contribution during baseflow conditions.

  6. Marine Geology

    NASA Astrophysics Data System (ADS)

    van Andel, Tjeerd H.

    Marine geology was blessed early, about 30 years ago, with two great textbooks, one by P.H. Kuenen, the other by Francis P. Shepard, but in more recent years, no one has dared synthesize a field that has become so diverse and is growing so rapidly. There are many texts written for the beginning undergraduate student, mostly by marine geologists, but none can be handed conveniently to a serious advanced student or given to a colleague interested in what the field has wrought. The reason for this regrettable state is obvious; only an active, major scholar could hope to write such a book well, but the years would pass, his students dwindle, his grants vanish. He himself might be out of date before his book was. Kennett has earned a large measure of gratitude for his attempt to undertake this task. His personal price must have been high but so are our rewards.

  7. Core rotational dynamics and geological events

    PubMed

    Greff-Lefftz; Legros

    1999-11-26

    A study of Earth's fluid core oscillations induced by lunar-solar tidal forces, together with tidal secular deceleration of Earth's axial rotation, shows that the rotational eigenfrequency of the fluid core and some solar tidal waves were in resonance around 3.0 x 10(9), 1.8 x 10(9), and 3 x 10(8) years ago. The associated viscomagnetic frictional power at the core boundaries may be converted into heat and would destabilize the D" thermal layer, leading to the generation of deep-mantle plumes, and would also increase the temperature at the fluid core boundaries, perturbing the core dynamo process. Such phenomena could account for large-scale episodes of continental crust formation, the generation of flood basalts, and abrupt changes in geomagnetic reversal frequency.

  8. Geologic Map of the Thaumasia Region, Mars

    USGS Publications Warehouse

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

    2001-01-01

    objective is to determine the distribution and ages of valleys. In our study, we incorporated detailed photogeologic mapping, comprehensive crater statistics (table 1), and geologic, paleotectonic, and paleoerosional Geographic Information System (GIS) databases. Sheets 1–3 show geologic units, faults and other significant structures, and valleys, respectively. To help unravel the complex geologic history of the Thaumasia region, we transferred the highly detailed geologic unit, paleotectonic, and paleoerosional information of sheets 1–3 into a multilayered GIS database for comparative analysis. The geologic information was transferred from hard copy into a digital format by scanning at 25 micron resolution on a drum scanner. The 2-bit scanned image was then converted to an x,y coordinate system using ARC/INFO's vectorization routine. The geologic unit, structural, and erosional data were transformed into the original map projection, Lambert Conformal. The average transformation root mean square error was 0.25 km (acceptable for the Thaumasia map base at 1:5,000,000 scale). After transformation, the features were properly attributed and tediously checked. Once digitized, the map data can be transformed into any map projection depending on the type of data analysis. For example, the equal-area sinusoidal projection was used for determining the precise area of geologic units (table 1). In addition to the geologic map and its attendant stratigraphic section, correlation chart, and description of map units, we include text sections that clarify the histories and temporal, spatial, and causal relations of the various geologic units and landforms of the Thaumasia region. The geologic summary section defines the sequence of major geologic events.

  9. Determination of the steam volume fraction in the event of loss of cooling of the spent fuel storage pool

    NASA Astrophysics Data System (ADS)

    Sledkov, R. M.; Galkin, I. Yu.; Stepanov, O. E.; Strebnev, N. A.

    2017-01-01

    When one solves engineering problems related to the cooling of fuel assemblies (FAs) in a spent fuel storage pool (SFSP) and the assessment of nuclear safety of FA storage in an SFSP in the initial event of loss of SFSP cooling, it is essential to determine the coolant density and, consequently, steam volume fractions φ in bundles of fuel elements at a pressure of 0.1-0.5 MPa. Such formulas for calculating φ that remain valid in a wide range of operating parameters and geometric shapes of channels and take the conditions of loss of SFSP cooling into account are currently almost lacking. The results of systematization and analysis of the available formulas for φ are reported in the present study. The calculated values were compared with the experimental data obtained in the process of simulating the conditions of FA cooling in an SFSP in the event of loss of its cooling. Six formulas for calculating the steam volume fraction, which were used in this comparison, were chosen from a total of 11 considered relations. As a result, the formulas producing the most accurate values of φ in the conditions of loss of SFSP cooling were selected. In addition, a relation that allows one to perform more accurate calculations of steam volume fractions in the conditions of loss of SFSP cooling was derived based on the Fedorov formula in the two-group approximation.

  10. Okinawa, Japan: Geologic Battleground

    NASA Astrophysics Data System (ADS)

    Waymack, S. W.; Carrington, M. P.; Harpp, K. S.

    2005-12-01

    One of our main goals as instructors, particularly in introductory courses, is to impart students with an appreciation of how geology has influenced the course of human events. Despite the apparent accessibility of such topics, communicating this in a lively, relevant, and effective way often proves difficult. We use a series of historical events, the Pacific island hopping campaign of WWII, to engage students in an active, guided inquiry exercise to explore how terrain and the underlying geology of an area can shape historical events. Teams of students are assigned the role of planning either the defense or occupation of Okinawa Island, in the Ryukyu arc, in a theoretical version of the 1945 conflict. Students are given a package of information, including geologic and topographic maps, a list of military resources available to them at the time, and some historical background. Students also have access to "reconnaissance" images, 360o digital panoramas of the landscape of Okinawa, keyed to their maps. Each team has a week to plan their strategies and carry out additional research, which they subsequently bring to the table in the form of a written battle plan. With an instructor as arbiter, teams alternate drawing their maneuvers on a map of the island, to which the other team then responds. This continues one move at a time, until the instructor declares a victor. Throughout the exercise, the instructor guides students through analysis of each strategic decision in light of the island's structure and topography, with an emphasis on the appropriate interpretation of the maps. Students soon realize that an understanding of the island's terrain literally meant the difference between life and death for civilians and military participants alike in 1945. The karst landscape of Okinawa posed unique obstacles to both the Japanese and the American forces, including difficult landing sites, networks of natural caves, and sequences of hills aligned perpendicular to the

  11. 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

  12. 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

  13. Determination of Hydraulically Activated Fractures and Field Stress Tensors in the Barnett Shale Using Microseismic Events Data

    NASA Astrophysics Data System (ADS)

    Busetti, S.

    2012-12-01

    Seismic moment and stress tensor inversions are applied to microseismic events data to investigate the mechanical behavior of activated fractures during hydraulic fracturing in tight reservoirs. The goal is to understand the likelihood of different mechanisms for induced microseismicity, including low pressure fluid leak-off or stress shadowing adjacent to bi-wing parent hydraulic fractures, and pressurized network flow with no parent fracture. The data includes 7,444 microseismic events generated from 18 sequential pumping stages in two adjacent horizontal wells in the Barnett Shale, recorded from two down-hole monitor wells. A tensile source model is used to derive parameters such as nodal plane orientations and slip vectors from the six component moment tensor for each microseismic event. Three-dimensional stress analysis techniques and a linearized stress inversion scheme are used to calculate geomechanical parameters. Four scenarios are considered. The first case considers fractures seismically activated in the in-situ stress field, which is determined from wellbore break-out data in the vertical wells. Fracture activation is assumed to occur by minor stress perturbations with no stress rotation. The second case also considers that the most unstable fractures in the wellbore state of stress activated, but to determine the induced stress state, stress inversion on only the unstable fractures is used. The third case assumes that all of the nodal planes are mechanically valid but that the plane with the lowest misfit, the angle between the observed and predicted slip vector, is the correct one. In this case, the wellbore stress state is ignored entirely and stress inversion on all of the nodal planes is used to solve for the activation stress. The fourth case expands case three by selecting the correct fault plane as the one with the highest instability in the inversion stress state and a second inversion is used on only the unstable fractures. Preliminary

  14. Sag-ponding and its Significance in determining Paleo-seismic events along the active strike- slip fault

    NASA Astrophysics Data System (ADS)

    Li, C.; Zhang, P.; Yuan, D.

    2007-12-01

    , associated with the slipping of the fault. 3. Faulting pattern of the sag-ponding Observations indicate that the deposition rhythm is concerned with the periodic behavior of the faulting. During the long-term activity of the fault, when the strain accumulates to some extent, the fault will move suddenly and violently, then come into a relative quiet period. This leads to the grains courser downside and finer upside in one rhythm in the sag-pond. If the fault acts like this several times, it will form a sequence composed of several deposition rhythms. 4. Slip amounts estimated by transverse variations of the depositional rhythm. One rhythm in a sag-pond represents a sag-ponding process. As a result of the strike-slipping, the pre-formed deposition center migrates with the movement of the fault in a direction parallel to the strike of the fault trace. By measuring the location variation of each of the deposition centers, we can determine the amounts of horizontal displacements of sag-ponding sediments in each pond. 5. Paleo-seismic events reflected by vertical variations of depositional rhythms Every rhythm of the deposition is the product of one slip event of the fault. These rhythmic structures actually reflect the abruptness and periodicity of the movement of the fault, which are really paleoearthquake events and their reoccur intervals. It can be inferred that each sag-ponding rhythm corresponds to a paleoearthquake event, thus the sag-ponding deposition sequence can be discussed in contrast with the paleoearthquake event sequence.

  15. Determining the Probability that a Small Event in Brazil (magnitude 3.5 to 4.5 mb) will be Followed by a Larger Event

    NASA Astrophysics Data System (ADS)

    Assumpcao, M.

    2013-05-01

    A typical earthquake story in Brazil: A swarm of small earthquakes starts to occur near a small town, reaching magnitude 3.5, causing some alarm but no damage. The freightened population, not used to feeling earthquakes, calls the seismology experts who set up a local network to study the seismicity. To the usual and inevitable question "Are we going to have a larger earthquake?", the usual and standard answer "It is not possible to predict earthquakes; larger earthquakes are possible". Fearing unecessary panic, seismologists often add that "however, large earthquakes are not very likely". This vague answer has proven quite inadequate. "Not very likely" is interpreted by the population and authorities as "not going to happen, and there is not need to do anything". Before L'Aquila 2009, one case of magnitude 3.8 in Eastern Brazil was followed seven months later by a magnitude 4.9 causing serious damage to poorly built houses. One child died and the affected population felt deceived by the seismologists. In order to provide better answers than just a vague "not likely", we examined the Brazilian catalog of earthquakes for all cases of moderate magnitude (3.4 mb or larger) that were followed, up to one year later, by a larger event. We found that the chance of an event with magnitude 3.4 or larger being the foreshock of a larger magntitude is roughly 1/6. The probability of an event being a foreshock varies with magnitude from about 20% for a 3.5 mb to about 5% for a 4.5 mb. Also, given that an event in the range 3.4 to 4.3 is a foreshock, the probability that the mainshock will be 4.7 or larger is 1/6. The probability for a larger event to occur decreases with time after the occurrence of the possible foreshock with a time constant of ~70 days. Perhaps, by giving the population and civil defense a more quantitative answer (such as "the chance of a larger even is like rolling a six in a dice") may help the decision to reinforce poor houses or even evacuate people from

  16. Streptococcus pneumoniae R6 interspecies transformation: genetic analysis of penicillin resistance determinants and genome-wide recombination events.

    PubMed

    Sauerbier, Julia; Maurer, Patrick; Rieger, Martin; Hakenbeck, Regine

    2012-11-01

    Interspecies gene transfer has been implicated as the major driving force for the evolution of penicillin resistance in Streptococcus pneumoniae. Genomic alterations of S. pneumoniae R6 introduced during four successive transformations with DNA of the high-level penicillin-resistant Streptococcus mitis B6 with beta-lactam selection have now been determined and the contribution of genes to high resistance levels was analysed genetically. Essential for high level resistance to penicillins of the transformant CCCB was the combination of murM(B) (6) and the 3' region of pbp2b(B) (6) . Sequences of both genes were detected in clinical isolates of S. pneumoniae, confirming the participation of S. mitis in the global gene pool of beta-lactam resistance determinants. The S. mitis PBP1b gene which contains an authentic stop codon within the transpeptidase domain is now shown to contribute only marginal to resistance, but it is possible that the presence of its transglycosylase domain is important in the context of cognate PBPs. The genome sequence of CCCB revealed 36 recombination events, including deletion and acquisition of genes and repeat elements. A total of 78 genes were affected representing 67 kb or 3.3% of the genome, documenting extensive alterations scattered throughout the genome.

  17. Knob heights within circum-Caloris geologic units on Mercury: Interpretations of the geologic history of the region

    NASA Astrophysics Data System (ADS)

    Ackiss, S. E.; Buczkowski, D. L.; Ernst, C. M.; McBeck, J. A.; Seelos, K. D.

    2015-11-01

    The circum-Caloris geologic units show morphology consistent with ejecta-derived formation, however crater counts suggest the units formed after the basin. To determine if the surrounding units are directly related to basin formation or products of later volcanic resurfacing events, we measured the heights and densities of knobs in 22 study regions to the east of the Caloris basin in three geologic units circumferential to the basin: the Odin Formation, the Van Eyck Formation, and the Smooth Plains Formation. In these study regions the size and concentration of ejecta blocks generally decrease away from the crater rim. The morphology that superposes the knobs and the distribution of knob heights within each study region suggests that the knobs were deposited as ejecta and later embayed by one or multiple volcanic events. The distribution of knob height and concentration indicates that the knobs within the circum-Caloris units are related to the formation of the basin.

  18. 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)

  19. 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)

  20. ATP binding and hydrolysis-driven rate-determining events in the RFC-catalyzed PCNA clamp loading reaction.

    PubMed

    Sakato, Miho; Zhou, Yayan; Hingorani, Manju M

    2012-02-17

    The multi-subunit replication factor C (RFC) complex loads circular proliferating cell nuclear antigen (PCNA) clamps onto DNA where they serve as mobile tethers for polymerases and coordinate the functions of many other DNA metabolic proteins. The clamp loading reaction is complex, involving multiple components (RFC, PCNA, DNA, and ATP) and events (minimally: PCNA opening/closing, DNA binding/release, and ATP binding/hydrolysis) that yield a topologically linked clamp·DNA product in less than a second. Here, we report pre-steady-state measurements of several steps in the reaction catalyzed by Saccharomyces cerevisiae RFC and present a comprehensive kinetic model based on global analysis of the data. Highlights of the reaction mechanism are that ATP binding to RFC initiates slow activation of the clamp loader, enabling it to open PCNA (at ~2 s(-1)) and bind primer-template DNA (ptDNA). Rapid binding of ptDNA leads to formation of the RFC·ATP·PCNA(open)·ptDNA complex, which catalyzes a burst of ATP hydrolysis. Another slow step in the reaction follows ATP hydrolysis and is associated with PCNA closure around ptDNA (8 s(-1)). Dissociation of PCNA·ptDNA from RFC leads to catalytic turnover. We propose that these early and late rate-determining events are intramolecular conformational changes in RFC and PCNA that control clamp opening and closure, and that ATP binding and hydrolysis switch RFC between conformations with high and low affinities, respectively, for open PCNA and ptDNA, and thus bookend the clamp loading reaction.

  1. Effect of a Founder Event on Variation in the Genetic Sex-Determining System of the Fire Ant Solenopsis Invicta

    PubMed Central

    Ross, K. G.; Vargo, E. L.; Keller, L.; Trager, J. C.

    1993-01-01

    Effects of a recent founder event on genetic diversity in wild populations of the fire ant Solenopsis invicta were studied, with particular attention given to the genetic sex-determining system. Diploid males are far more common relative to haploid males in introduced populations than in native populations of fire ants, and queens that produce diploid males account for a significantly larger proportion of the mated queens in introduced than in native populations. Differences between native and introduced populations in attributes of the mating systems (i.e., queen mating frequency or level of inbreeding) can be excluded as factors contributing to these different levels of diploid male production. Thus, we conclude that diploid males have increased in frequency in introduced populations because of a loss of allelic diversity at the sex-determining locus (loci). This loss of sex alleles has generated a substantial increase in the estimated segregational genetic load associated with production of sterile diploid males in introduced populations over the load in native populations. The loss of allelic diversity in the sex-determining system in introduced S. invicta is paralleled by a loss of electrophoretically detectable rare alleles at protein-encoding loci. Such concordance between these different types of markers is predicted because each of the many sex alleles present in the native populations is expected to be rare. Estimates of expected heterozygosity (H(exp)) based on 76 electrophoretic loci do not differ significantly between the native and introduced fire ant populations, illustrating the lack of sensitivity of this measure for detecting many types of bottlenecks. PMID:8293983

  2. A model for a drug distribution system in remote Australia as a social determinant of health using event structure analysis.

    PubMed

    Rovers, John P; Mages, Michelle D

    2017-09-25

    The social determinants of health include the health systems under which people live and utilize health services. One social determinant, for which pharmacists are responsible, is designing drug distribution systems that ensure patients have safe and convenient access to medications. This is critical for settings with poor access to health care. Rural and remote Australia is one example of a setting where the pharmacy profession, schools of pharmacy, and regulatory agencies require pharmacists to assure medication access. Studies of drug distribution systems in such settings are uncommon. This study describes a model for a drug distribution system in an Aboriginal Health Service in remote Australia. The results may be useful for policy setting, pharmacy system design, health professions education, benchmarking, or quality assurance efforts for health system managers in similarly remote locations. The results also suggest that pharmacists can promote access to medications as a social determinant of health. The primary objective of this study was to propose a model for a drug procurement, storage, and distribution system in a remote region of Australia. The secondary objective was to learn the opinions and experiences of healthcare workers under the model. Qualitative research methods were used. Semi-structured interviews were performed with a convenience sample of 11 individuals employed by an Aboriginal health service. Transcripts were analyzed using Event Structure Analysis (ESA) to develop the model. Transcripts were also analyzed to determine the opinions and experiences of health care workers. The model was comprised of 24 unique steps with seven distinct components: choosing a supplier; creating a list of preferred medications; budgeting and ordering; supply and shipping; receipt and storage in the clinic; prescribing process; dispensing and patient counseling. Interviewees described opportunities for quality improvement in choosing suppliers, legal issues and

  3. Determining Nurse Aide Staffing Requirements to Provide Care Based on Resident Workload: A Discrete Event Simulation Model.

    PubMed

    Schnelle, John F; Schroyer, L Dale; Saraf, Avantika A; Simmons, Sandra F

    2016-11-01

    Nursing aides provide most of the labor-intensive activities of daily living (ADL) care to nursing home (NH) residents. Currently, most NHs do not determine nurse aide staffing requirements based on the time to provide ADL care for their unique resident population. The lack of an objective method to determine nurse aide staffing requirements suggests that many NHs could be understaffed in their capacity to provide consistent ADL care to all residents in need. Discrete event simulation (DES) mathematically models key work parameters (eg, time to provide an episode of care and available staff) to predict the ability of the work setting to provide care over time and offers an objective method to determine nurse aide staffing needs in NHs. This study had 2 primary objectives: (1) to describe the relationship between ADL workload and the level of nurse aide staffing reported by NHs; and, (2) to use a DES model to determine the relationship between ADL workload and nurse aide staffing necessary for consistent, timely ADL care. Minimum Data Set data related to the level of dependency on staff for ADL care for residents in over 13,500 NHs nationwide were converted into 7 workload categories that captured 98% of all residents. In addition, data related to the time to provide care for the ADLs within each workload category was used to calculate a workload score for each facility. The correlation between workload and reported nurse aide staffing levels was calculated to determine the association between staffing reported by NHs and workload. Simulations to project staffing requirements necessary to provide ADL care were then conducted for 65 different workload scenarios, which included 13 different nurse aide staffing levels (ranging from 1.6 to 4.0 total hours per resident day) and 5 different workload percentiles (ranging from the 5th to the 95th percentile). The purpose of the simulation model was to determine the staffing necessary to provide care within each workload

  4. [Determination of blood alcohol level of people who are involved in a judicial event of medical importance (case report)].

    PubMed

    Alkan, N; Demircan, T

    2001-10-01

    In some cases, determination of blood alcohol level is very important. The alcohol level at the time of an event, can affect the court decision and may lead to aggravate the penalty or on the contrary an acquittal. In this article, a criminal action, in one of Turkish High Criminal Court is examined. The case was about the death of a drunk person who had fallen down from the window of his girl friend's house which is on the third floor of an apartment. This person's parent applied to public prosecutor saying that their child did not fall down but was murdered by his girl friend. During this trial, in the victim's autopsy, no alcohol detected in blood in contrast with his girl friend's testimony. Because of this contradiction, a reasonable doubt has emerged that she was the murderer in this suspicious death. However, in the further stages of trial, the reasons of no alcohol detection in the autopsy is investigated. In the basis of this case, the importance and techniques of alcohol detection in blood is discussed with literature.

  5. Predicting post-event processing in social anxiety disorder following two prototypical social situations: state variables and dispositional determinants.

    PubMed

    Kiko, Sonja; Stevens, Stephan; Mall, Anna Katharina; Steil, Regina; Bohus, Martin; Hermann, Christiane

    2012-10-01

    This study investigated self-reported state (anxiety, physical symptoms, cognitions, internally focused attention, safety behaviors, social performance) and trait (social anxiety, depressive symptoms, dysfunctional self-consciousness) predictors of post-event processing (PEP) subsequent to two social situations (interaction, speech) in participants with a primary diagnosis of social anxiety disorder (SAD) and healthy controls (HC). The speech triggered significantly more intense PEP, especially in SAD. Regardless of the type of social situation, PEP was best predicted by situational anxiety and dysfunctional cognitions among the state variables. If only trait variables were considered, PEP following both situations was accounted for by trait social anxiety. In addition, dysfunctional self-consciousness contributed to PEP-speech. If state and trait variables were jointly considered, for both situations, situational anxiety and dysfunctional cognitions were confirmed as the most powerful PEP predictors above and beyond trait social anxiety (interaction) and dysfunctional self-consciousness (speech). Hence, PEP as assessed on the day after a social situation seems to be mainly determined by state variables. Trait social anxiety and dysfunctional self-consciousness also significantly contribute to PEP depending on the type of social situation. The present findings support dysfunctional cognitions as a core cognitive mechanism for the maintenance of SAD. Implications for treatment are discussed.

  6. Integrating geology and perforating

    SciTech Connect

    Araujo, P.F. de; Souza Padilha, S.T.C. de

    1997-02-01

    Perforating is a very common well completion operation. Usually, it is considered to be as simple as making holes in casing. Actually, perforating is one of the most critical tasks for establishing a path from reservoir rock to borehole form which hydrocarbons can flow to surface. The objective of this article is to relate perforating technology with geological aspects and completion type to determine the best shooting equipment (gun type, charge and differential pressure) to perform the most efficient perforating job. Several subjects related to formation geology are taken into account for a shooting job, such as: compressive strength, reservoir pressure and thickness, lithology type, porosity and permeability, ratio between horizontal and vertical permeabilities, and fluid type. Gun geometry used in the oil industry incorporates several parameters, including shot density, hole entrance diameter, gun phase and jet penetration. API tests are done on perforating guns to define applicability and performance. A new geometrical parameter is defined as the relative angle of the jet, which is the angle between the jet tunnel and formation dip. GEOCAN is a methodology which relates geology to gun geometry and type to define the most efficient gun system for perforated completions. It uses the intelligent perforating technique with the SPAN (Schlumberger Perforating Analysis) program to confirm optimum gun choice.

  7. History of Geology.

    ERIC Educational Resources Information Center

    Greene, Mott T.

    1985-01-01

    Discusses: (1) geologists and the history of geology; (2) American historians and the history of geology; (3) history of geology in the 1980s; (4) sources for the history of geology (bibliographies, dictionaries, encyclopedias, handbooks, periodicals, public/official histories, compilations, and books); (5) research opportunities; and (6) other…

  8. Direct determination of the ionic charge distribution of helium and iron in He-3-rich solar energetic particle events

    NASA Technical Reports Server (NTRS)

    Klecker, B.; Hovestadt, D.; Scholer, M.; Gloeckler, G.; Ipavich, F. M.; Fan, C. Y.; Fisk, L. A.

    1984-01-01

    The first direct measurement of the ionic charge distribution of the helium isotopes and of iron in (He-3)-Fe-rich solar energetic particle events is reported. No significant contribution of singly ionized helium to the events is found. The two-sigma upper limits for the He-3(+)/He-3(2+) and He-4(+)/He-4(2+) ratios are 0.02 and 0.03, respectively. The mean charge state of iron found by averaging five (He-3)-Fe-rich solar energetic particle events is 19 + or -2, significantly larger than the iron charge state for energetic solar particles in normal composition events. These results appear to favor the resonant heating model proposed by Fisk (1978). It is concluded that temperatures in the source region exceed 5 million K in the events under study.

  9. The onset of childhood amnesia in childhood: a prospective investigation of the course and determinants of forgetting of early-life events.

    PubMed

    Bauer, Patricia J; Larkina, Marina

    2014-01-01

    The present research was an examination of the onset of childhood amnesia and how it relates to maternal narrative style, an important determinant of autobiographical memory development. Children and their mothers discussed unique events when the children were 3 years of age. Different subgroups of children were tested for recall of the events at ages 5, 6, 7, 8, and 9 years. At the later session they were interviewed by an experimenter about the events discussed 2 to 6 years previously with their mothers (early-life events). Children aged 5, 6, and 7 remembered 60% or more of the early-life events. In contrast, children aged 8 and 9 years remembered fewer than 40% of the early-life events. Overall maternal narrative style predicted children's contributions to mother-child conversations at age 3 years; it did not have cross-lagged relations to memory for early-life events at ages 5 to 9 years. Maternal deflections of the conversational turn to the child predicted the amount of information children later reported about the early-life events. The findings have implications for our understanding of the onset of childhood amnesia and the achievement of an adult-like distribution of memories in the school years. They highlight the importance of forgetting processes in explanations of the amnesia.

  10. The onset of childhood amnesia in childhood: A prospective investigation of the course and determinants of forgetting of early-life events

    PubMed Central

    Bauer, Patricia J.; Larkina, Marina

    2013-01-01

    The present research was an examination of the onset of childhood amnesia and how it relates to maternal narrative style, an important determinant of autobiographical memory development. Children and their mothers discussed unique events when the children were 3 years of age. Different subgroups of children were tested for recall of the events at ages 5, 6, 7, 8, and 9 years. At the later session, they were interviewed by an experimenter about the events discussed 2 to 6 years previously with their mothers (early-life events). Children ages 5, 6, and 7 remembered 60% or more of the early-life events. In contrast, children ages 8 and 9 years remembered fewer than 40% of the early-life events. Overall maternal narrative style predicted children's contributions to mother-child conversations at age 3 years; it did not have cross-lagged relations to memory for early-life events at ages 5 to 9 years. Maternal deflections of the conversational turn to the child predicted the amount of information children later reported about the early-life events. The findings have implications for our understanding of the onset of childhood amnesia and the achievement of an adult-like distribution of memories in the school years. They highlight the importance of forgetting processes in explanations of the amnesia. PMID:24236647

  11. 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

  12. 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.; hide

    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

  13. Diagnostic Utility of Systematic Aquaporin-4 Antibodies Determination in the First Event of Immune-Mediated Optic Neuritis.

    PubMed

    Carnero Contentti, Edgar; De Virgiliis, Mariana; Hryb, Javier Pablo; Leguizamon, Felisa; Celso, Julia; Di Pace, José Luis; Perassolo, Mónica

    2016-01-01

    Antibodies against aquaporin-4 (AQP4-ab) have diagnostic and prognostic value. However, little is known to date about their utility in the first event of optic neuritis (ON). To evaluate the utility of systematic AQP4-ab determination in a retrospective cohort of patients with a first onset of ON. All patients (n = 42) were tested for AQP4-ab in the following context: typical ON (TON) and atypical ON (AON). Clinical, radiological and biochemical data were collected; patients with TON vs. AON and AQP4-ab positive vs. negative were compared. The proportion of AQP4-ab seropositive patients was 40% in the TON group vs. 40.9% in the AON group. Visual acuity (VA) at baseline was poor in AON patients (p = 0.02) and these patients were associated with worse VA outcome (p < 0.001) at 6 months compared with TON patients, with a median follow-up of 3.27 ± 1.79 years. Brain MRI with dissemination in space criteria (p < 0.001), spinal cord partial lesions (p < 0.001) and oligoclonal bands (p = 0.02) were associated with the initial stages of TON. VA severity, number of myelitis attacks and ON relapses did not differ significantly between seropositive and seronegative patients. AQP4-ab were detected only in neuromyelitis optica spectrum disorders patients. This study showed a high seropositivity for AQP4-ab in TON patients, suggesting that it could diagnostic utility at the onset of ON. © 2016 S. Karger AG, Basel.

  14. Value of epidemiologic studies in determining the true incidence of adverse events. The nonsteroidal anti-inflammatory drug story.

    PubMed

    Miwa, L J; Jones, J K; Pathiyal, A; Hatoum, H

    1997-10-13

    Evidence supporting differential toxic effects of nonsteroidal anti-inflammatory drugs (NSAIDs) often is derived from spontaneous reports of adverse events to the US Food and Drug Administration (FDA). These reports represent observations from an undefined, exposed population that are not collected in a standardized manner and therefore are subject to reporting biases. Epidemiologic studies, in which the numbers of patients experiencing an adverse event and exposed to the drug are known, provide more reliable measures of risk and can place spontaneous reports in perspective. To compare both data sources with regard to NSAID-associated gastrointestinal, liver, and skin events. We obtained spontaneous reports of these adverse events for diclofenac, nabumetone, naproxen, and piroxicam. Published epidemiologic studies of these events were reviewed. Spontaneous reports did not mirror reliably the results of epidemiologic studies. Spontaneous reports showed higher associations of gastrointestinal and skin events with nabumetone and piroxicam and hepatic events with diclofenac. Epidemiologic studies generally did not show differential risk among these NSAIDs. When the 4 NSAIDs are compared in epidemiologic studies, there is no quantitative basis for identifying 1 as more or less toxic than the others, underlining the hazard of deriving quantitative conclusions from spontaneous reports. Spontaneous reports are an unreliable measure of risk; rather, they may provide evidence of the relative awareness of specific toxic effects among physicians.

  15. Comparison of hypocenters and their uncertainties determined by three location methods: A case study on hydro-fracturing microseismic events recorded at a dense sub-surface array

    NASA Astrophysics Data System (ADS)

    Woo, J. U.; Rhie, J.; Kim, J. H.

    2015-12-01

    The hypocenters of microseismic events induced by hydro-fracturing for developing shale gas provide important information on the characteristics of the fracture networks. This information is crucial to evaluate the production rate and also make a plan for efficient hydro-fracturing design. Therefore, the accurate hypocenter determination of microseismic events is very important from the economic point of view and the tolerable location error should be only dozens of meters for this purpose. In this study, we test three methods, which are widely used for locating earthquakes in seismology, to determine the hypocenters of microseismic events generated during the commercial shale gas development and recorded at a dense sub-surface array. We selected 1-hour time window and applied automatic picking algorithm to identify events and measure P and S arrival times of them. Our automatic picking algorithm identified 84 events in given time window and 73 of them are reliably located by all three methods. The first method is based on linear and iterative inversion and locates individual events separately. The second method simultaneously locates clustered events and reduces location errors due to incorrect velocity model by introducing the station terms. The third method locates only relative rather than absolute locations of clustered events using double difference algorithm. 1D P and S-wave velocity models are constructed based on well-logging data. Automatically measured P and S arrival times are used for determining absolute locations and relative arrival times measured by waveform cross-correlation are utilized for relative locations. Our preliminary result indicates that double difference method combined with waveform cross-correlations is more applicable than other two methods in that it satisfies the required accuracy for the microseismic monitoring.

  16. Standardless determination of Nd and Sr isotope ratios in geological samples using LA-MC-ICP-MS with a low-oxide molecular yield interface setup

    NASA Astrophysics Data System (ADS)

    Kimura, J.; Chang, Q.; Takahashi, T.; Kawabata, H.

    2013-12-01

    We investigated an appropriate instrumental setup for a laser-ablation multiple-collector inductively coupled plasma mass spectrometer (LA-MC-ICP-MS) and found that a reduced oxide setting allowed accurate and precise analyses of Sr and Nd isotope ratios in geological samples with concomitant interfering elements (Kr and Rb on Sr and Sm on Nd). We used an Aridus II solution-excimer laser dual-intake system. The ICP interface used normal sample and skimmer cones with torch shield switched-OFF and an additional large interface rotary pump. The setting accomplished reduced oxide levels NdO+/Nd+ <0.01%, without significant sacrifice of the instrumental sensitivity (c.a. 70%). Oxide molecular ions for the lighter elements were negligible and accurate internal mass bias corrections were achieved for Sr, Sm, and Nd using isotopic ratios derived from thermal ionization mass spectrometry measurements. However, elemental fractionation between Rb and Sr and Nd and Sm still exists due perhaps to elemental fractionation in the ICP preventing standardless determination of parent-daughter ratios. For Sr isotope measurement, a new analytical protocol was developed for correcting Kr baseline-induced biases. Residual analytical biases of 84Sr/86Sr and 87Sr/86Sr were observed after applying on-peak background subtractions and mass-fractionation corrections using internal normalization. The residual biases occurred only for samples analysed with LA and not for solution analyses using Aridus II with the same instrumental setup. We concluded that this was due to suppression and enhancement of the Kr baseline by loading of the LA sample aerosols and by the introduction of Kr from the samples, respectively. We found that both the 84Sr/86Sr and 87Sr/86Sr isotope ratios were affected proportionally by the baseline biases of the LA analyses of an isotopically homogeneous anorthite plagioclase, and similar result were seen in theoretical calculations. A theoretical bias correction for the 87

  17. Applications of ISES for geology

    NASA Technical Reports Server (NTRS)

    Bowker, David E.

    1990-01-01

    The principal applications for onboard data processing and real-time data transmission in the geological sciences are the detection of early warning signs of potential catastrophic events and the rapid assessment of impact and damage following major events. Also, the opportunity for quick look and supporting data during field investigations should not be disregarded. The Eos platforms are ideal for these applications because of the variety of earth sensing instruments and their differing modes of operation. Further study is required to define the role for each instrument and to assess how they can aid each other in establishing an improved output product.

  18. Transport, vertical structure and radiative properties of dust events in southeast China determined from ground and space sensors

    SciTech Connect

    Liu, Jianjun; Zheng, Y.; Li, Zhanqing; Flynn, Connor J.; Welton, Ellsworth J.; Cribb, Maureen

    2011-11-01

    Two dust events were detected over the Yangtze Delta region of China during March 14-17 and April 25-26 in 2009 where such dust events are uncommon. The transport behavior, spatio-temporal evolution, vertical structure, direct radiative effects, as well as induced heating rates, are investigated using a combination of ground-based and satellite-based measurements, a back-trajectory analysis, an aerosol model and a radiative transfer model.

  19. Native American Students' Understanding of Geologic Time Scale: 4th-8th Grade Ojibwe Students' Understanding of Earth's Geologic History

    ERIC Educational Resources Information Center

    Nam, Younkyeong; Karahan, Engin; Roehrig, Gillian

    2016-01-01

    Geologic time scale is a very important concept for understanding long-term earth system events such as climate change. This study examines forty-three 4th-8th grade Native American--particularly Ojibwe tribe--students' understanding of relative ordering and absolute time of Earth's significant geological and biological events. This study also…

  20. Geologic Mapping of Mars

    NASA Astrophysics Data System (ADS)

    Price, Katherine H.

    1998-05-01

    Planetary geologic mapping involves integrating a terrestrial-based understanding of surface and subsurface processes and mapping principles to investigate scientific questions. Mars mappers must keep in mind that physical processes, such as wind and flowing water on Mars, are or were different from terrestrial processes because the planetary atmospheres have changed differently over time. Geologic mapping of Mars has traditionally been done by hand using overlays on photomosaics of Viking Orbiter and Mariner images. Photoclinometry and shadow measurements have been used to determine elevations, and the distribution and size of craters have been used to determine the relative ages of surfaces- more densely cratered surfaces are older. Some mappers are now using computer software (ranging from Photoshop to ArcInfo) to facilitate mapping, though their applications must be carefully executed so that registration of the images remains true. Images and some mapping results are now available on the internet, and new data from recent missions to Mars (Pathfinder and Surveyor) will offer clarifying information to mapping efforts. This paper consists chiefly of pictures and diagrams.

  1. Bringing Field Geology to a High School Audience: Connecting to the Next Generation of Scientific Minds through Science Olympiad

    NASA Astrophysics Data System (ADS)

    Baker, A. M.; Schroeder, D. M.; Van Hecke, M.

    2011-12-01

    with a number of related questions or tasks that would require them to interpret and integrate the data from those sources. Some example tasks could include the creation of topographic profiles, converting between map projections, creating geologic cross-sections, determining relative ages of a set of deposits, or assessing a specific location for potential geohazard risk. The implementation of this event in competitions across the country is an excellent opportunity for early career scientists to get involved by hosting the event at regional- or state-level competitions. We will provide information and resources for interested early career and other scientists to get involved with their local regional or state competitions as writers, proctors, mentors, etc.

  2. Comparative determinants of 4-year cardiovascular event rates in stable outpatients at risk of or with atherothrombosis.

    PubMed

    Bhatt, Deepak L; Eagle, Kim A; Ohman, E Magnus; Hirsch, Alan T; Goto, Shinya; Mahoney, Elizabeth M; Wilson, Peter W F; Alberts, Mark J; D'Agostino, Ralph; Liau, Chiau-Suong; Mas, Jean-Louis; Röther, Joachim; Smith, Sidney C; Salette, Geneviève; Contant, Charles F; Massaro, Joseph M; Steg, Ph Gabriel

    2010-09-22

    Clinicians and trialists have difficulty with identifying which patients are highest risk for cardiovascular events. Prior ischemic events, polyvascular disease, and diabetes mellitus have all been identified as predictors of ischemic events, but their comparative contributions to future risk remain unclear. To categorize the risk of cardiovascular events in stable outpatients with various initial manifestations of atherothrombosis using simple clinical descriptors. Outpatients with coronary artery disease, cerebrovascular disease, or peripheral arterial disease or with multiple risk factors for atherothrombosis were enrolled in the global Reduction of Atherothrombosis for Continued Health (REACH) Registry and were followed up for as long as 4 years. Patients from 3647 centers in 29 countries were enrolled between 2003 and 2004 and followed up until 2008. Final database lock was in April 2009. Rates of cardiovascular death, myocardial infarction, and stroke. A total of 45,227 patients with baseline data were included in this 4-year analysis. During the follow-up period, a total of 5481 patients experienced at least 1 event, including 2315 with cardiovascular death, 1228 with myocardial infarction, 1898 with stroke, and 40 with both a myocardial infarction and stroke on the same day. Among patients with atherothrombosis, those with a prior history of ischemic events at baseline (n = 21,890) had the highest rate of subsequent ischemic events (18.3%; 95% confidence interval [CI], 17.4%-19.1%); patients with stable coronary, cerebrovascular, or peripheral artery disease (n = 15,264) had a lower risk (12.2%; 95% CI, 11.4%-12.9%); and patients without established atherothrombosis but with risk factors only (n = 8073) had the lowest risk (9.1%; 95% CI, 8.3%-9.9%) (P < .001 for all comparisons). In addition, in multivariable modeling, the presence of diabetes (hazard ratio [HR], 1.44; 95% CI, 1.36-1.53; P < .001), an ischemic event in the previous year (HR, 1.71; 95% CI, 1

  3. Social Determinants of Depression: Social Cohesion, Negative Life Events, and Depression Among People Living with HIV/Aids in Nigeria, West Africa.

    PubMed

    Shittu, Rasaki O; Issa, Baba A; Olanrewaju, Ganiyu T; Mahmoud, Abdulraheem O; Odeigah, Louis O; Sule, Abdullateef G

    2014-01-01

    People Living with HIV/AIDS (PLWHA) continue to face persistent and deep rooted social barriers. Incidentally, studies in social determinants of depression are very limited, necessitating this study, which examined social determinants of depression and the impact of these determinants on depression. This was a hospital based, cross sectional descriptive study of three hundred adult HIV/AIDS patients, attending the HIV clinic of Kwara State Specialist Hospital, Sobi, Ilorin, Nigeria. Depressive symptoms were measured by the PHQ-9 rating scale. Three variables of social determinants of depression: socio-economic status (years of school and self-reported economic status of family), social cohesion, and negative life events were examined. The self-reported economic status of the family varied from good 35(11.7%), average 162(54%), and poor among 103(34.3%) of the respondents. Social cohesion was low in 199(66.3%), fair in 65(21.7%) and high among 36(12%) of the respondents. There was significant association between social cohesion, negative life events, and depression. Income was the most significant socio-economic determinant. Majority had very low social cohesion and more negative life events, while those with below average years of schooling were more depressed. These are statistically significant. Social determinants of depression should be given a lot of emphasis, when addressing the issue of depression, if we are to meaningfully tackle this increasing scourge in our society.

  4. Social Determinants of Depression: Social Cohesion, Negative Life Events, and Depression Among People Living with HIV/Aids in Nigeria, West Africa

    PubMed Central

    Shittu, Rasaki O.; Issa, Baba A.; Olanrewaju, Ganiyu T.; Mahmoud, Abdulraheem O.; Odeigah, Louis O.; Sule, Abdullateef G.

    2014-01-01

    Background: People Living with HIV/AIDS (PLWHA) continue to face persistent and deep rooted social barriers. Incidentally, studies in social determinants of depression are very limited, necessitating this study, which examined social determinants of depression and the impact of these determinants on depression. Methods: This was a hospital based, cross sectional descriptive study of three hundred adult HIV/AIDS patients, attending the HIV clinic of Kwara State Specialist Hospital, Sobi, Ilorin, Nigeria. Depressive symptoms were measured by the PHQ-9 rating scale. Three variables of social determinants of depression: socio-economic status (years of school and self-reported economic status of family), social cohesion, and negative life events were examined. Results: The self-reported economic status of the family varied from good 35(11.7%), average 162(54%), and poor among 103(34.3%) of the respondents. Social cohesion was low in 199(66.3%), fair in 65(21.7%) and high among 36(12%) of the respondents. There was significant association between social cohesion, negative life events, and depression. Conclusion and Global Health Implications: Income was the most significant socio-economic determinant. Majority had very low social cohesion and more negative life events, while those with below average years of schooling were more depressed. These are statistically significant. Social determinants of depression should be given a lot of emphasis, when addressing the issue of depression, if we are to meaningfully tackle this increasing scourge in our society. PMID:27621970

  5. 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)

  6. 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)

  7. Geology for the Masses

    ERIC Educational Resources Information Center

    Dickinson, William R.

    1970-01-01

    Describes environmental geology as including planning to avoid natural hazards, acquire natural resources, and use land wisely. Describes philosophy and strategies for developing interdisciplinary, environmental geology education at the high school, college, professional graduate, and doctoral research levels. (PR)

  8. Neutron Absorption in Geological Material

    NASA Astrophysics Data System (ADS)

    Løvhøiden, G.; Andersen, E.

    1990-01-01

    Thermal neutron absorption cross section of geological samples is determined with the steady state neutron source method. Cross section measurements of North Sea sediments demonstrate that also materials with high contents of clay minerals may be investigated with the steady state method.

  9. Historical sketch: Radar geology

    NASA Technical Reports Server (NTRS)

    Macdonald, H.

    1980-01-01

    A chronological assessment is given of the broad spectra of technology associated with radar geology. Particular attention is given to the most recent developments made in the areas of microwave Earth resources applications and geologic remote sensing from aircraft and satellite. The significance of space derived radar in geologic investigations is discussed and the scientific basis for exploiting the sensitivity of radar signals to various aspects of geologic terrain is given.

  10. Skylab ATM/S-056 X-ray event analyzer: Instrument description, parameter determination, and analysis example (15 June 1973 1B/M3 flare)

    NASA Technical Reports Server (NTRS)

    Wilson, R. M.

    1976-01-01

    The Skylab ATM/S-056 X-Ray Event Analyzer, part of an X-ray telescope experiment, is described. The techniques employed in the analysis of its data to determine electron temperatures and emission measures are reviewed. The analysis of a sample event - the 15 June 1973 1B/M3 flare - is performed. Comparison of the X-Ray Event Analyzer data with that of the SolRad 9 observations indicates that the X-Ray Event Analyzer accurately monitored the sun's 2.5 to 7.25 A X-ray emission and to a lesser extent the 6.1 to 20 A emission. A mean average peak temperature of 15 million K at 1,412 UT and a mean average peak electron density (assuming a flare volume of 10 to the 13 power cu km) of 27 million/cu mm at 1,416 to 1,417 UT are deduced for the event. The X-Ray Event Analyzer data, having a 2.5 s time resolution, should be invaluable in comparisons with other high-time resolution data (e.g., radio bursts).

  11. Simultaneous Determination of Structure and Event Location Using Body and Surface Wave Measurements at a Single Station: Preparation for Mars Data from the InSight Mission

    NASA Astrophysics Data System (ADS)

    Panning, M. P.; Banerdt, W. B.; Beucler, E.; Blanchette-Guertin, J. F.; Boese, M.; Clinton, J. F.; Drilleau, M.; James, S. R.; Kawamura, T.; Khan, A.; Lognonne, P. H.; Mocquet, A.; van Driel, M.

    2015-12-01

    An important challenge for the upcoming InSight mission to Mars, which will deliver a broadband seismic station to Mars along with other geophysical instruments in 2016, is to accurately determine event locations with the use of a single station. Locations are critical for the primary objective of the mission, determining the internal structure of Mars, as well as a secondary objective of measuring the activity of distribution of seismic events. As part of the mission planning process, a variety of techniques have been explored for location of marsquakes and inversion of structure, and preliminary procedures and software are already under development as part of the InSight Mars Quake and Mars Structure Services. One proposed method, involving the use of recordings of multiple-orbit surface waves, has already been tested with synthetic data and Earth recordings. This method has the strength of not requiring an a priori velocity model of Mars for quake location, but will only be practical for larger events. For smaller events where only first orbit surface waves and body waves are observable, other methods are required. In this study, we implement a transdimensional Bayesian inversion approach to simultaneously invert for basic velocity structure and location parameters (epicentral distance and origin time) using only measurements of body wave arrival times and dispersion of first orbit surface waves. The method is tested with synthetic data with expected Mars noise and Earth data for single events and groups of events and evaluated for errors in both location and structural determination, as well as tradeoffs between resolvable parameters and the effect of 3D crustal variations.

  12. Using Vertical electrical sounding survey and refraction seismic survey for determining the geological layers depths, the structural features and assessment groundwater in Aqaba area in South Jordan.

    NASA Astrophysics Data System (ADS)

    Akawwi, Emad; Alzoubi, Abdallah; Ben Abraham, Zvi; Rahamn Abo Alades, Abdel; Alrzouq, Rami; Tiber, Gidon; Neimi, Tina

    2010-05-01

    The study area is the Aqaba region (Southern wadi Araba basin). Aqaba region area located at 87900 and 89000 North and 147000 and 158000 East (Palestine grid). Tectonically Aqaba area lies within the tectonic plate boundary along the Arabian and African plate slide. This plate boundary comprises numerous and shot fault segments. The main aims of this study are to assessing the groundwater potential and its quality, to explain the subsurface geological conditions and support the ongoing geological, environmental and hydrogeological studies. Therefore, it was anticipated that the results of the geophysical surveying will give many different important parameters as The subsurface geological features, thicknesses of the different lithological units, depth to the bed rocks and depth to the water table. The groundwater can apply an important role in ensuring sustainable water supply in the area. This study was carried out in order to assess groundwater condition, geological layers thicknesses and structural features in Aqaba area by using vertical electrical sounding (VES) surveys and refraction seismic techniques. There are three geoelectrical cross section were carried out at different sites by using the Schlumberger array. The first cross section indicated three layers of different resistivity. The second cross section indicated four layers of different resistivity. The third geoelectrical cross sections indicated three layers. The refraction seismic method also has been conducted in the same area as VES. About 12 refraction seismic profiles have been carried out in the study area. The length of the first profile was 745 m at the direction N-S. This profile indicated two different layers with a different velocities. The length of the second profile was 1320 m with E-W direction. This profile indicated two different layers. The length of the third profile was about 515 m with a direction SE-NW. It recognized two different layers with a different velocities. The fourth

  13. The "Large" in Large Igneous Provinces: Using Digital Geological Maps to Determine the Area, Magma Flux, and Potential Environmental Impact of the Wrangellia Flood Basalts

    NASA Astrophysics Data System (ADS)

    Scoates, J. S.; Greene, A. R.; Weis, D. A.

    2010-12-01

    Large igneous provinces (LIPs), such as continental flood basalts and oceanic plateaus, are formed by relatively short duration, massive outpourings of basalt in intraplate settings. Their emplacement has been associated with global climatic and biotic change (e.g., end-Permian Siberian LIP). The magmatic products of a LIP typically cover an area >1 Mkm2, however erosion and exhumation may substantially reduce the original area and volume of a LIP, especially oceanic plateaus that have been tectonically dispersed during accretion (e.g., Caribbean, Wrangellia). The availability of digital geologic maps from government geologic surveys now allows for measuring the precise areal distribution of remnant LIP-products, which is essential information for estimating total volumes and ultimately potential environmental effects. The Wrangellia flood basalts represent one of the best-exposed accreted oceanic plateaus on Earth. This Triassic LIP is exposed in numerous fault-bound blocks in a belt extending discontinuously for 2300 km in the Pacific Northwest of North America. It contains exposures of submarine and subaerial volcanic rocks representing composite stratigraphic thicknesses of 3.5-6 km. From recently compiled digital geologic maps (British Columbia, Yukon, Alaska), the mapped exposures of the Wrangellia flood basalts are relatively small (25,256 km2 with 75% from Vancouver Island), which leads to minimum calculated erupted volumes of up to 1.4 x 105 km3 and an estimated magma flux of 0.03 km3/yr. The original areal distribution was substantially greater, perhaps by an order of magnitude or more, as the outcrop extent does not include regions covered by younger strata and surficial deposits nor does it account for the volcanic component of the terrane that may have been subducted. However, even this minimum volumetric output rate is comparable to recent estimates of long-term volumetric eruption rates for ocean islands such as Iceland (0.02-0.04 km3/yr) and Hawaii

  14. Atomic-absorption determination of mercury in geological materials by flame and carbon-rod atomisation after solvent extraction and using co-extracted silver as a matrix modifier

    USGS Publications Warehouse

    Sanzolone, R.F.; Chao, T.T.

    1983-01-01

    Based on modifications and expansion of the original Tindall's solvent extraction flame atomic-absorption procedure, an atomic-absorption spectrophotometric method has been developed for the determination of mercury in geological materials. The sample is digested with nitric and hydrochloric acids in a boiling water-bath. The solution is made ammoniacal and potassium iodide and silver nitrate are added. The mercury is extracted into isobutyl methyl ketone as the tetraiodomercurate(ll). Added silver is co-extracted with mercury and serves as a matrix modifier in the carbon-rod atomiser. The mercury in the isobutyl methyl ketone extract may be determined by either the flame- or the carbon-rod atomisation method, depending on the concentration level. The limits of determination are 0.05-10 p.p.m. of mercury for the carbon-rod atomisation and 1 -200 p.p.m. of mercury for the flame atomisation. Mercury values for reference samples obtained by replicate analyses are in good agreement with those reported by other workers, with relative standard deviations ranging from 2.3 to 0.9%. Recoveries of mercury spiked at two levels were 93-106%. Major and trace elements commonly found in geological materials do not interfere.

  15. Shuttle Imaging Radar - Geologic applications

    NASA Technical Reports Server (NTRS)

    Macdonald, H.; Bridges, L.; Waite, W.; Kaupp, V.

    1982-01-01

    The Space Shuttle, on its second flight (November 12, 1981), carried the first science and applications payload which provided an early demonstration of Shuttle's research capabilities. One of the experiments, the Shuttle Imaging Radar-A (SIR-A), had as a prime objective to evaluate the capability of spaceborne imaging radars as a tool for geologic exploration. The results of the experiment will help determine the value of using the combination of space radar and Landsat imagery for improved geologic analysis and mapping. Preliminary analysis of the Shuttle radar imagery with Seasat and Landsat imagery from similar areas provides evidence that spaceborne radars can significantly complement Landsat interpretation, and vastly improve geologic reconnaissance mapping in those areas of the world that are relatively unmapped because of perpetual cloud cover.

  16. Geological Survey research 1978

    USGS Publications Warehouse

    ,

    1978-01-01

    This U.S. Geological Survey activities report includes a summary of 1978 fiscal year scientific and economic results accompanied by a list of geologic and hydrologic investigations in progress and a report on the status of topographic mapping. The summary of results includes: (1) Mineral and water resources, (2) Engineering geology and hydrology, (3) Regional geology, (4) Principles and processes, (5) Laboratory and field methods, (6) Topographic surveys and mapping, (7) Management of resources on public lands, (8) Land information and analysis, and (9) Investigations in other countries. Also included are lists of cooperating agencies and Geological Survey offices. (Woodard-USGS)

  17. Geological Survey research 1976

    USGS Publications Warehouse

    ,

    1976-01-01

    This U.S. Geological Survey activities report includes a summary of recent (1976 fiscal year) scientific and economic results accompanied by a list of geologic and hydrologic investigations in progress and a report on the status of topographic mapping. The summary of results includes: (1) Mineral resources, Water resources, (2) Engineering geology and hydrology, (3) Regional geology, (4) Principles and processes, (5) Laboratory and field methods, (6) Topographic surveys and mapping, (7) Management of resources on public lands, (8) Land information and analysis, and (9) Investigations in other countries. Also included are lists of cooperating agencies and Geological Survey offices. (Woodard-USGS)

  18. Source parameters for small events associated with the 1986 North Palm Springs, California, earthquake determined using empirical Green functions

    USGS Publications Warehouse

    Mori, J.; Frankel, A.

    1990-01-01

    Using small events as empirical Green functions, source parameters were estimated for 25 ML 3.4 to 4.4 events associated with the 1986 North Palm Springs earthquake. The static stress drops ranged from 3 to 80 bars, for moments of 0.7 to 11 ?? 1021 dyne-cm. There was a spatial pattern to the stress drops of the aftershocks which showed increasing values along the fault plane toward the northwest compared to relatively low values near the hypocenter of the mainshock. The highest values were outside the main area of slip, and are believed to reflect a loaded area of the fault that still has an higher level of stress which was not released during the main shock. -from Authors

  19. Forensic geology exhumed

    NASA Astrophysics Data System (ADS)

    Martinez, Joseph Didier

    Forensic geology binds applied geology to the world of legal controversy and action. However, the term “forensic” is often misconstrued. Although even some attorneys apply it only to the marshalling of evidence in criminal cases, it has a much broader definition. One dictionary defines it as “pertaining to, connected with, or used in courts of law or public discussion and debate.” The American Geological Institute's Glossary of Geology defines forensic geology as “the application of the Earth sciences to the law.” The cited reference to Murray and Tedrow [1975], however, deals mostly if not exclusively with the gathering and use of evidence in criminal cases, despite the widespread involvement of geologists in more general legal matters. It seems appropriate to “exhume” geology's wider application to the law, which is encompassed by forensic geology.

  20. Geology orbiter comparison study

    NASA Technical Reports Server (NTRS)

    Cutts, J. A. J.; Blasius, K. R.; Davis, D. R.; Pang, K. D.; Shreve, D. C.

    1977-01-01

    Instrument requirements of planetary geology orbiters were examined with the objective of determining the feasibility of applying standard instrument designs to a host of terrestrial targets. Within the basic discipline area of geochemistry, gamma-ray, X-ray fluorescence, and atomic spectroscopy remote sensing techniques were considered. Within the discipline area of geophysics, the complementary techniques of gravimetry and radar were studied. Experiments using these techniques were analyzed for comparison at the Moon, Mercury, Mars and the Galilean satellites. On the basis of these comparative assessments, the adaptability of each sensing technique was judged as a basic technique for many targets, as a single instrument applied to many targets, as a single instrument used in different mission modes, and as an instrument capability for nongeoscience objectives.

  1. Geological terrain models

    NASA Technical Reports Server (NTRS)

    Kaupp, V. H.; Macdonald, H. C.; Waite, W. P.

    1981-01-01

    The initial phase of a program to determine the best interpretation strategy and sensor configuration for a radar remote sensing system for geologic applications is discussed. In this phase, terrain modeling and radar image simulation were used to perform parametric sensitivity studies. A relatively simple computer-generated terrain model is presented, and the data base, backscatter file, and transfer function for digital image simulation are described. Sets of images are presented that simulate the results obtained with an X-band radar from an altitude of 800 km and at three different terrain-illumination angles. The simulations include power maps, slant-range images, ground-range images, and ground-range images with statistical noise incorporated. It is concluded that digital image simulation and computer modeling provide cost-effective methods for evaluating terrain variations and sensor parameter changes, for predicting results, and for defining optimum sensor parameters.

  2. Spacecraft Solar Particle Event (SPE) Shielding: Shielding Effectiveness as a Function of SPE model as Determined with the FLUKA Radiation Transport Code

    NASA Technical Reports Server (NTRS)

    Koontz, Steve; Atwell, William; Reddell, Brandon; Rojdev, Kristina

    2010-01-01

    Analysis of both satellite and surface neutron monitor data demonstrate that the widely utilized Exponential model of solar particle event (SPE) proton kinetic energy spectra can seriously underestimate SPE proton flux, especially at the highest kinetic energies. The more recently developed Band model produces better agreement with neutron monitor data ground level events (GLEs) and is believed to be considerably more accurate at high kinetic energies. Here, we report the results of modeling and simulation studies in which the radiation transport code FLUKA (FLUktuierende KAskade) is used to determine the changes in total ionizing dose (TID) and single-event environments (SEE) behind aluminum, polyethylene, carbon, and titanium shielding masses when the assumed form (i. e., Band or Exponential) of the solar particle event (SPE) kinetic energy spectra is changed. FLUKA simulations have fully three dimensions with an isotropic particle flux incident on a concentric spherical shell shielding mass and detector structure. The effects are reported for both energetic primary protons penetrating the shield mass and secondary particle showers caused by energetic primary protons colliding with shielding mass nuclei. Our results, in agreement with previous studies, show that use of the Exponential form of the event

  3. Determination of (alpha)-dialkylamino acids and their Enantiomers in Geological Samples by High-Performance Liquid Chromatography after Dervatization with a Chiral Adduct of (omicron)-Phthaldialdehyde

    NASA Technical Reports Server (NTRS)

    Zhoa, Meixun; Bada, Jeffrey L.

    1995-01-01

    Derivatization with (omicron)-phthaldialdehyde (OPA) and the chiral thiol N-acetyl-L-cysteine (NAC) is a convenient and sensitive technique for the HPLC detection and resolution of protein amino acid enantiomers. The kinetics of the reaction of OPA-NAC with (alpha)-dialkylamino acids was investigated. The fluorescence yield of (alpha)-dialkylamino acids was only about 10% of that of protein amino acids when the derivatization was carried out at room temperature for 1-2 min, which is the procedure generally used for protein amino acid analyses. The fluorescence yield of (alpha)-dialkylamino acids can be enhanced by up to ten-fold when the derivatization reaction time is increased to 15 min at room temperature. The OPA-NAC technique was optimized for the detection and enantiomeric resolution of a-dialkylamino acids in geological samples which contain a large excess of protein amino acids. The estimated detection limit for a-dialkylamino acids is 1-2 pmol, comparable to that for protein amino acids.

  4. Determination of porosity and facies trends in a complex carbonate reservoir, by using 3-D seismic, borehole tools, and outcrop geology

    SciTech Connect

    Zacharakis, T.G. Jr.; Comet, J.N.; Murillo, A.A.

    1996-08-01

    Mesozoic carbonate reservoirs are found in the Mediterranean Sea, off the east coast of Spain. A wide variation of porosities are found in the core samples and logs: vuggy, breccia, fractures, and cavern porosity. In addition, complex Tertiary carbonate geometries include olistostromes, breccia bodies, and reef buildups, which are found on top of Mesozoic carbonates. Predicting the porosity trends within these oil productive reservoirs requires an understanding of how primary porosity was further enhanced by secondary processes, including fractures, karstification, and dolomitization in burial conditions. Through an extensive investigation of field histories, outcrop geology, and seismic data, a series of basic reservoir styles have been identified and characterized by well log signature and seismic response. The distribution pattern of the different reservoirs styles is highly heterogeneous, but by integrating subsurface data and outcrop analogs, it is possible to distinguish field-scale and local patterns of both vertical and local variations in reservoir properties. Finally, it is important to quantify these reservoir properties through the study of seismic attributes, such as amplitude variations, and log responses at the reservoir interval. By incorporating 3-D seismic data, through the use of seismic inversion, it is possible to predict porosity trends. Further, the use of geostatistics can lead to the prediction of reservoir development within the carbonate facies.

  5. Simultaneous determination of major to ultratrace elements in geological samples by fusion-dissolution and inductively coupled plasma mass spectrometry techniques.

    PubMed

    García de Madinabeitia, S; Sánchez Lorda, M E; Ibarguchi, J I Gil

    2008-09-12

    A method has been developed for the simultaneous quantification of major to ultratrace elements in geological samples using quadrupole ICP-MS techniques. The sample preparation involves fusion with LiBO2 and dilution in HNO3-HF which allows complete decomposition of refractory minerals and quantification of the elements of interest. The effects of high Total Dissolved Solids (TDS) and Li in the solution are minimized using a matrix-tolerant interface and conditioning the instrument with LiBO2 solution. The signal drift is moreover controlled using conventional internal standards and specific Drift Correction Standards (DCS). A key issue of the technique is the external calibration using selected Certified Reference Materials (CRM). Depending on the sample type and analytes of interest three optimized programmable modes are used sequentially: Standard, Collision Cell (CCT) and Kinetic Energy Discrimination (KED) mode. The method allows to quantify more than 40 elements in concentrations from tens-of-percent to <0.1 ppm levels during a single experiment. The method has been validated through the analysis of different CRMs with recovery factors of ca. 100% and typical 2sigma errors of <10%.

  6. Preliminary applications of Landsat images and aerial photography for determining land-use, geologic, and hydrologic characteristics, Yampa River basin, Colorado and Wyoming

    USGS Publications Warehouse

    Heimes, F.J.; Moore, G.K.; Steele, T.D.

    1978-01-01

    Expanded energy- and recreation-related activities in the Yampa River basin, Colorado and Wyoming, have caused a rapid increase in economic development which will result in increased demand and competition for natural resources. In planning for efficient allocation of the basin 's natural resources, Landsat images and small-scale color and color-infrared photographs were used for selected geologic, hydrologic and land-use applications within the Yampa River basin. Applications of Landsat data included: (1) regional land-use classification and mapping, (2) lineament mapping, and (3) areal snow-cover mapping. Results from the Landsat investigations indicated that: (1) Landsat land-use classification maps, at a regional level, compared favorably with areal land-use patterns that were defined from available ground information, (2) lineaments were mapped in sufficient detail using recently developed techniques for interpreting aerial photographs, (3) snow cover generally could be mapped for large areas with the exception of some densely forested areas of the basin and areas having a large percentage of winter-season cloud cover. Aerial photographs were used for estimation of turbidity for eight stream locations in the basin. Spectral reflectance values obtained by digitizing photographs were compared with measured turbidity values. Results showed strong correlations (variances explained of greater than 90 percent) between spectral reflectance obtained from color photographs and measured turbidity values. (Woodard-USGS)

  7. Synthesis of a new molecularly imprinted polymer for sorption of the silver ions from geological and antiseptic samples for determination by flame atomic absorption spectrometry.

    PubMed

    Hashemi-Moghaddam, Hamid; Yahyazadeh, Faegheh; Vardini, Mohammad Taghi

    2014-01-01

    A new molecularly imprinted polymer (MIP) was synthesized using methacrylic acid (functional monomer), ethylene glycol dimethacrylate (crosslinker), 2,2'-azobisisobutironitril (initiator), silver (Ag) dithizone complex (template), and chloroform (porogenic solvent). This process was a noncovalent, bulk, thermal radical-polymerization. To compare the performance of this polymer, control polymer (nonimprinted polymer) was prepared under well-defined conditions without the use of a template. Extraction experiments were performed on the MIP and a nonimprinted polymer. Then, various parameters were optimized, such as pH, time, concentration of sample, and type of eluent for elution of Ag from polymer. In addition, interfering effects were investigated on the absorption of Ag by the MIP. This polymer was used for the rapid extraction and preconcentration of Ag from an antiseptic and geological sample. Finally, the amount of Ag was measured by flame atomic absorption spectrometry after preconcentration by the synthesized MIP, and results were compared with a direct inductively coupled plasma method. The results showed high performance of this method in preconcentration of Ag.

  8. Is what goes in what comes out? Encoding and retrieval event-related potentials together determine memory outcome.

    PubMed

    Chen, Yvonne Y; Lithgow, Kirstie; Hemmerich, Jumjury A; Caplan, Jeremy B

    2014-10-01

    Understanding memory function amounts to identifying how events (cognitive and neural) at study eventually influence events at test. Many of the proposed cognitive correlates of memory-related event-related potentials (ERPs) at study resemble proposed cognitive correlates of other memory-related ERPs, recorded at test. We wondered whether a given known ERP feature at study might in fact reflect an effective-encoding process that is, in turn, tapped by another specific ERP feature, recorded at test. To this end, we asked which pairs of known memory-related ERP features explain common variance across a large sample of participants, while they perform a word-recognition task. Two early ERP features, the Late Positive Component (study) and the FN400 (test), covaried significantly. These features also correlated with memory success (d' and response time). Two later ERP features, the Slow Wave (study) and the Late Parietal Positivity (test), also covaried when lures were incorporated into the analysis. Interestingly, these later features were uncorrelated with memory outcome. This novel approach, exploiting naturally occurring subject variability (in strategy and ERP amplitudes), informs our understanding of the memory functions of ERP features in several ways. Specifically, they strengthen the argument that the earlier ERP features may drive old/new recognition (but perhaps not the later features). Our findings suggest the Late Positive Component at study, in some degree, may cause the FN400 to increase at test, together producing effective recognition memory. The Slow Wave at study appears to relate the Left Parietal Positivity at test, but these may play roles in more complex memory judgments and may be less critical for simple old/new recognition.

  9. Single-Event Upset (SEU) model verification and threshold determination using heavy ions in a bipolar static RAM

    NASA Technical Reports Server (NTRS)

    Zoutendyk, J. A.; Smith, L. S.; Soli, G. A.; Thieberger, P.; Wegner, H. E.

    1985-01-01

    Single-Event Upset (SEU) response of a bipolar low-power Schottky-diode-clamped TTL static RAM has been observed using Br ions in the 100-240 MeV energy range and O ions in the 20-100 MeV range. These data complete the experimental verification of circuit-simulation SEU modeling for this device. The threshold for onset of SEU has been observed by the variation of energy, ion species and angle of incidence. The results obtained from the computer circuit-simulation modeling and experimental model verification demonstrate a viable methodology for modeling SEU in bipolar integrated circuits.

  10. Single-Event Upset (SEU) model verification and threshold determination using heavy ions in a bipolar static RAM

    NASA Technical Reports Server (NTRS)

    Zoutendyk, J. A.; Smith, L. S.; Soli, G. A.; Thieberger, P.; Wegner, H. E.

    1985-01-01

    Single-Event Upset (SEU) response of a bipolar low-power Schottky-diode-clamped TTL static RAM has been observed using Br ions in the 100-240 MeV energy range and O ions in the 20-100 MeV range. These data complete the experimental verification of circuit-simulation SEU modeling for this device. The threshold for onset of SEU has been observed by the variation of energy, ion species and angle of incidence. The results obtained from the computer circuit-simulation modeling and experimental model verification demonstrate a viable methodology for modeling SEU in bipolar integrated circuits.

  11. An Investigation into Understanding of Geological Time among 10- and 11-Year-Old Children.

    ERIC Educational Resources Information Center

    Trend, Roger

    1998-01-01

    Focuses on the understanding of British children (N=189) of geologic time as they participate in related activities. Indicates that 10- and 11-year-old children lack a clear chronology of geologic events. Contains 22 references. (DDR)

  12. Geologic mapping of MTM quads 40292 and 40297: In the Utopian lowlands north of the Nilosyrtis Mensae, Mars

    NASA Technical Reports Server (NTRS)

    Williams, Steven H.; Zimbelman, James R.

    1991-01-01

    Geologic mapping at 1:500,000 scale of the Mars transverse Mercator (MTM) quads 40292 and 40297 is being conducted under the auspices of the Mars Geologic Mapping Program. The study area is located in the southwestern portion of Utopia Planitia immediately north of the Nilosyrtis Mensae, between latitudes 37.5 and 42.5 degrees and longitudes 290 and 300 degrees. The goals of the mapping are to identify the major geologic features in the study area and to determine the sequence and scope of the geologic events that have modified the lowland side of the global dichotomy boundary in this region in order to at least partially constrain models of dichotomy boundary origin and evolution. The progress made towards achieving these goals is reported.

  13. Hydromechanical coupling in geologic processes

    USGS Publications Warehouse

    Neuzil, C.E.

    2003-01-01

    Earth's porous crust and the fluids within it are intimately linked through their mechanical effects on each other. This paper presents an overview of such "hydromechanical" coupling and examines current understanding of its role in geologic processes. An outline of the theory of hydromechanics and rheological models for geologic deformation is included to place various analytical approaches in proper context and to provide an introduction to this broad topic for nonspecialists. Effects of hydromechanical coupling are ubiquitous in geology, and can be local and short-lived or regional and very long-lived. Phenomena such as deposition and erosion, tectonism, seismicity, earth tides, and barometric loading produce strains that tend to alter fluid pressure. Resulting pressure perturbations can be dramatic, and many so-called "anomalous" pressures appear to have been created in this manner. The effects of fluid pressure on crustal mechanics are also profound. Geologic media deform and fail largely in response to effective stress, or total stress minus fluid pressure. As a result, fluid pressures control compaction, decompaction, and other types of deformation, as well as jointing, shear failure, and shear slippage, including events that generate earthquakes. By controlling deformation and failure, fluid pressures also regulate states of stress in the upper crust. Advances in the last 80 years, including theories of consolidation, transient groundwater flow, and poroelasticity, have been synthesized into a reasonably complete conceptual framework for understanding and describing hydromechanical coupling. Full coupling in two or three dimensions is described using force balance equations for deformation coupled with a mass conservation equation for fluid flow. Fully coupled analyses allow hypothesis testing and conceptual model development. However, rigorous application of full coupling is often difficult because (1) the rheological behavior of geologic media is complex

  14. Age-specific vibrissae growth rates: a tool for determining the timing of ecologically important events in Steller sea lions

    USGS Publications Warehouse

    Rea, L.D.; Christ, A.M.; Hayden, A.B.; Stegall, V.K.; Farley, S.D.; Stricker, Craig A.; Mellish, J.E.; Maniscalco, John M.; Waite, J.N.; Burkanov, V.N.; Pitcher, K.W.

    2015-01-01

    Steller sea lions (SSL; Eumetopias jubatus) grow their vibrissae continually, providing a multiyear record suitable for ecological and physiological studies based on stable isotopes. An accurate age-specific vibrissae growth rate is essential for registering a chronology along the length of the record, and for interpreting the timing of ecologically important events. We utilized four methods to estimate the growth rate of vibrissae in fetal, rookery pup, young-of-the-year (YOY), yearling, subadult, and adult SSL. The majority of vibrissae were collected from SSL live-captured in Alaska and Russia between 2000 and 2013 (n = 1,115), however, vibrissae were also collected from six adult SSL found dead on haul-outs and rookeries during field excursions to increase the sample size of this underrepresented age group. Growth rates of vibrissae were generally slower in adult (0.44 ± 0.15 cm/mo) and subadult (0.61 ± 0.10 cm/mo) SSL than in YOY (0.87 ± 0.28 cm/mo) and fetal (0.73 ± 0.05 cm/mo) animals, but there was high individual variability in these growth rates within each age group. Some variability in vibrissae growth rates was attributed to the somatic growth rate of YOY sea lions between capture events (P = 0.014, r2 = 0.206, n = 29).

  15. Method of analysis at the U.S. Geological Survey California Water Science Center, Sacramento Laboratory - determination of haloacetic acid formation potential, method validation, and quality-control practices

    USGS Publications Warehouse

    Zazzi, Barbara C.; Crepeau, Kathryn L.; Fram, Miranda S.; Bergamaschi, Brian A.

    2005-01-01

    An analytical method for the determination of haloacetic acid formation potential of water samples has been developed by the U.S. Geological Survey California Water Science Center Sacramento Laboratory. The haloacetic acid formation potential is measured by dosing water samples with chlorine under specified conditions of pH, temperature, incubation time, darkness, and residual-free chlorine. The haloacetic acids formed are bromochloroacetic acid, bromodichloroacetic acid, dibromochloroacetic acid, dibromoacetic acid, dichloroacetic acid, monobromoacetic acid, monochloroacetic acid, tribromoacetic acid, and trichloroacetic acid. They are extracted, methylated, and then analyzed using a gas chromatograph equipped with an electron capture detector. Method validation experiments were performed to determine the method accuracy, precision, and detection limit for each of the compounds. Method detection limits for these nine haloacetic acids ranged from 0.11 to 0.45 microgram per liter. Quality-control practices include the use of blanks, quality-control samples, calibration verification standards, surrogate recovery, internal standard, matrix spikes, and duplicates.

  16. Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory; determination of organochlorine pesticides and polychlorinated biphenyls in bottom sediment by dual capillary-column gas chromatography with electron-capture detection

    USGS Publications Warehouse

    Foreman, William T.; Connor, Brooke F.; Furlong, Edward T.; Vaught, Deborah G.; Merten, Leslie M.

    1995-01-01

    A method for the determination of 30 individual organochlorine pesticides, total toxaphene, and total polychlorinated biphenyls (PCBs) in bottom sediment is described. The method isolates the pesticides and PCBs by solvent extraction with dichlorobenzene, removes inorganic sulfur, large naturally occurring molecules, and other unwanted interferences by gel permeation chromatography, and further cleans up and class fractionates the extract using adsorption chromatography. The com- pounds then are instrumentally determined using dual capillary-column gas chromatography with electron-capture detection. Reporting limits range from 1 to 5 micrograms per kilogram for 30 individual pesticides, 50 micrograms per kilogram for total PCBs, and 200 micrograms per kilogram for total toxaphene. The method also is designed to allow the simultaneous isolation of 79 other semivolatile organic compounds from the sediment, which are separately quantified using gas chromatography with mass spectrometric detection. The method was developed in support of the U.S. Geological Survey's National Water-Quality Assessment program.

  17. Geomorphology in North American Geology Departments, 1971

    ERIC Educational Resources Information Center

    White, Sidney E.; Malcolm, Marshall D.

    1972-01-01

    Presents results of a 1970-71 survey of 350 geomorphologists and geology departments to determine what sort of geomorphology is being taught in the colleges and universities of the United States and Canada. (PR)

  18. Geomorphology in North American Geology Departments, 1971

    ERIC Educational Resources Information Center

    White, Sidney E.; Malcolm, Marshall D.

    1972-01-01

    Presents results of a 1970-71 survey of 350 geomorphologists and geology departments to determine what sort of geomorphology is being taught in the colleges and universities of the United States and Canada. (PR)

  19. Preliminary Stratigraphic Basis for Geologic Mapping of Venus

    NASA Technical Reports Server (NTRS)

    Basilevsky, A. T.; Head, J. W.

    1993-01-01

    The age relations between geologic formations have been studied at 36 1000x1000 km areas centered at the dark paraboloid craters. The geologic setting in all these sites could be characterized using only 16 types of features and terrains (units). These units form a basic stratigraphic sequence (from older to younger: (1) Tessera (Tt); (2-3) Densely fractured terrains associated with coronae (COdf) and in the form of remnants among plains (Pdf); (4) Fractured and ridged plains (Pfr); (5) Plains with wrinkle ridges (Pwr); (6-7) Smooth and lobate plains (Ps/Pl); and (8) Rift-associated fractures (Fra). The stratigraphic position of the other units is determined by their relation with the units of the basic sequence: (9) Ridge bells (RB), contemporary with Pfr; (10-11) Ridges of coronae and arachnoids annuli (COar/Aar), contemporary with wrinkle ridges of Pwr; (12) Fractures of coronae annuli (COaf) disrupt Pwr and Ps/Pl; (13) Fractures (F) disrupt Pwr or younger units; (14) Craters with associated dark paraboloids (Cdp), which are on top of all volcanic and tectonic units except the youngest episodes of rift-associated fracturing and volcanism; (15-16) Surficial streaks (Ss) and surficial patches (Sp) are approximately contemporary with Cdp. These units may be used as a tentative basis for the geologic mapping of Venus including VMAP. This mapping should test the stratigraphy and answer the question of whether this stratigraphic sequence corresponds to geologic events which were generally synchronous all around the planet or whether the sequence is simply a typical sequence of events which occurred in different places at diffferent times.

  20. Geologic age: using radioactive decay to determine geologic age

    USGS Publications Warehouse

    ,

    1997-01-01

    At the close of the 18th century, the haze of fantasy and mysticism that tended to obscure the true nature of the Earth was being swept away. Careful studies by scientists showed that rocks had diverse origins. Some rock layers, containing clearly identifiable fossil remains of fish and other forms of aquatic animal and plant life, originally formed in the ocean. Other layers, consisting of sand grains winnowed clean by the pounding surf, obviously formed as beach deposits that marked the shorelines of ancient seas. Certain layers are in the form of sand bars and gravel banks -- rock debris spread over the land by streams. Some rocks were once lava flows or beds of cinders and ash thrown out of ancient volcanoes; others are portions of large masses of once-molten rock that cooled very slowly far beneath the Earth's surface. Other rocks were so transformed by heat and pressure during the heaving and buckling of the Earth's crust in periods of mountain building that their original features were obliterated.

  1. Arrhythmia burden in elderly patients with severe aortic stenosis as determined by continuous electrocardiographic recording: toward a better understanding of arrhythmic events after transcatheter aortic valve replacement.

    PubMed

    Urena, Marina; Hayek, Salim; Cheema, Asim N; Serra, Vicenç; Amat-Santos, Ignacio J; Nombela-Franco, Luis; Ribeiro, Henrique B; Allende, Ricardo; Paradis, Jean-Michel; Dumont, Eric; Thourani, Vinod H; Babaliaros, Vasilis; Francisco Pascual, Jaume; Cortés, Carlos; Del Blanco, Bruno García; Philippon, François; Lerakis, Stamatios; Rodés-Cabau, Josep

    2015-02-03

    This study sought to evaluate the prevalence of previously undiagnosed arrhythmias in candidates for transcatheter aortic valve replacement (TAVR) and to determine the impact on therapy changes and arrhythmic events after the procedure. A total of 435 candidates for TAVR underwent 24-hour continuous ECG monitoring the day before the procedure. Newly diagnosed arrhythmias were observed in 70 patients (16.1%) before TAVR: paroxysmal atrial fibrillation (AF)/atrial tachycardia (AT) in 28, advanced atrioventricular block or severe bradycardia in 24, nonsustained ventricular tachycardia in 26, and intermittent left bundle-branch block in 3 patients. All arrhythmic events but one were asymptomatic and led to a therapy change in 43% of patients. In patients without known AF/AT, the occurrence of AF/AT during 24-hour ECG recording was associated with a higher rate of 30-day cerebrovascular events (7.1% versus 0.4%; P=0.030). Among the 53 patients with new-onset AF/AT after TAVR, 30.2% had newly diagnosed paroxysmal AF/AT before the procedure. In patients who needed permanent pacemaker implantation after the procedure (n=35), 31.4% had newly diagnosed advanced atrioventricular block or severe bradycardia before TAVR. New-onset persistent left bundle-branch block after TAVR occurred in 37 patients, 8.1% of whom had intermittent left bundle-branch block before the procedure. Newly diagnosed arrhythmias were observed in approximately a fifth of TAVR candidates, led to a higher rate of cerebrovascular events, and accounted for a third of arrhythmic events after the procedure. This high arrhythmia burden highlights the importance of an early diagnosis of arrhythmic events in such patients to implement the appropriate therapeutic measures earlier. © 2014 American Heart Association, Inc.

  2. The geology and geophysics of Mars

    NASA Technical Reports Server (NTRS)

    Saunders, R. S.

    1976-01-01

    The current state of knowledge concerning the regional geology and geophysics of Mars is summarized. Telescopic observations of the planet are reviewed, pre-Mariner models of its interior are discussed, and progress achieved with the Mariner flybys, especially that of Mariner 9, is noted. A map of the Martian geological provinces is presented to provide a summary of the surface geology and morphology. The contrast between the northern and southern hemispheres is pointed out, and the characteristic features of the surface are described in detail. The global topography of the planet is examined along with its gravitational field, gravity anomalies, and moment of inertia. The general sequence of events in Martian geological history is briefly outlined.

  3. Cloud and Stability Characteristics of Mid-latitude Continental Convective Snow Events as Determined From Serial Radiosonde Ascents

    NASA Astrophysics Data System (ADS)

    Market, P.; Heymsfield, A.; Bodner, M.; Podzimek, J.; Pettegrew, B.; Melick, C.; Smith, L.

    2005-05-01

    A field experiment is currently underway that seeks to document the evolution of tropospheric stability as well as the microphysical characteristics of the parent cloud during mid-latitude, continental convective snow events. A mobile sounding system, using radiosondes outfitted with an ice crystal replicator, is being deployed in the Midwestern United States during February and March 2005 in support of this study. Intense observing periods (IOP) involve transporting the mobile sounding system to a location where convective snowfall has been predicted. Each IOP features hourly radiosonde ascents for durations of up to 12 hours, with convective snowfall occurring near the middle of this period. Additionally, we expect to launch ice crystal replicators on one or two balloons closest to the time of convective snow occurrence. Data and analysis from these field campaigns will be presented.

  4. Sedimentology and petroleum geology

    SciTech Connect

    Bjorlykke, K.O. )

    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.

  5. Geological Survey research 1981

    USGS Publications Warehouse

    ,

    1982-01-01

    This U.S. Geological Survey activities report includes a summary of 1981 fiscal year scientific and economic results accompanied by a list of geologic, hydrologic, and cartographic investigations in progress. The summary of results includes: (1) Mineral, (2) Water resources, (3) Engineering geology and hydrology, (4) Regional geology, (5) Principles and processes, (6) Laboratory and field methods, (7) Topographic surveys and mapping, (8) Management of resources on public lands, (9) Land information and analysis, and (10) Investigations in other countries. Also included are lists of investigations in progress.

  6. PHOTOMICROPHOTOGRAPHY- GEOLOGY ( SEM)

    NASA Image and Video Library

    1972-10-13

    PHOTOMICROPHOTOGRAPHY -GEOLOGY (SEM) High magnification and resolution views of lunar, meteorite and terrestrial materials using the Scanning Electron MIcroscope (SEM), Bldg. 31 Planetary and Earth Science Laboratory.

  7. Alaska geology revealed

    USGS Publications Warehouse

    Wilson, Frederic H.; Labay, Keith A.

    2016-11-09

    This map shows the generalized geology of Alaska, which helps us to understand where potential mineral deposits and energy resources might be found, define ecosystems, and ultimately, teach us about the earth history of the State. Rock units are grouped in very broad categories on the basis of age and general rock type. A much more detailed and fully referenced presentation of the geology of Alaska is available in the Geologic Map of Alaska (http://dx.doi.org/10.3133/sim3340). This product represents the simplification of thousands of individual rock units into just 39 broad groups. Even with this generalization, the sheer complexity of Alaskan geology remains evident.

  8. Surficial geologic map of the southeast Memphis Quadrangle, Shelby County, Tennessee

    USGS Publications Warehouse

    Moore, David W.; Diehl, Sharon F.

    2004-01-01

    The depiction of geology on this map is designed to aid in urban planning and analysis of potential damage in the event of strong earthquake motion. The geologic map by itself does not analyze potential earthquake damage, but is designed to be used by seismologists who perform such analyses. Wind-deposited silt and clayey silt (loess) is the predominant surficial deposit. Loess entirely covers the upland (everyplace in the map area that is not a valley occupied by a stream) to depths of 4.5-16 m. The second most abundant deposit is silty alluvium, which is confined to the narrow floodplains and is 1-10 m thick. Sparse, unconsolidated, pebbly sand alluvium is 0.5-3 m thick and is confined to point bars and channel deposits in the narrow, incised channel of Nonconnah Creek. The nature of geologic materials to a degree determines the severity of damage to infrastructure sustained during a strong earthquake.

  9. Geology explorer: virtual geologic mapping and interpretation

    NASA Astrophysics Data System (ADS)

    Saini-Eidukat, Bernhardt; Schwert, Donald P.; Slator, Brian M.

    2002-12-01

    We are developing internet-based freeware for virtual mapping and geologic interpretation. This takes the form of a synthetic, virtual world, Planet Oit, where students are given the means and the equipment to carry out geologic investigation and interpretation as a geologist would in the field. The environment is designed to give students an authentic experience that includes elements of: (1) exploration of a spatially oriented, virtual, world; (2) practical, field oriented, expedition planning and decision-making; and (3) scientific problem solving (i.e. a "hands on" approach to mapping, geologic investigation, data acquisition, and interpretation). The game-like environment is networked, multi-player, and simulation-based. Planet Oit can be visited on the Internet at http://oit.cs.ndsu.nodak.edu/

  10. Rheology and density of glucose syrup and honey: Determining their suitability for usage in analogue and fluid dynamic models of geological processes

    NASA Astrophysics Data System (ADS)

    Schellart, W. P.

    2011-06-01

    glucose syrup and honey, respectively. The new results demonstrate that glucose syrups and (to a lesser degree) honeys are well suited for usage in analogue and fluid dynamic experiments to represent linear-viscous strain independent and shear rate independent rheologies to model geological processes. Glucose syrups have the added advantage of being more transparent than honeys, allowing for accurately resolving and quantifying flow patterns in the fluid during a model run.

  11. Geologic Map of the Umiat Quadrangle, Alaska

    USGS Publications Warehouse

    Mull, Charles G.; Houseknecht, David W.; Pessel, G.H.; Garrity, Christopher P.

    2004-01-01

    This geologic map of the Umiat quadrangle is a compilation of previously published USGS geologic maps and unpublished mapping done for the Richfield Oil Corporation. Geologic mapping from these three primary sources was augmented with additional unpublished map data from British Petroleum Company. This report incorporates recent revisions in stratigraphic nomenclature. Stratigraphic and structural interpretations were revised with the aid of modern high-resolution color infrared aerial photographs. The revised geologic map was checked in the field during the summers of 2001 and 2002. The geologic unit descriptions on this map give detailed information on thicknesses, regional distributions, age determinations, and depositional environments. The paper version of this map is available for purchase from the USGS Store.

  12. Drug Use and Other Determinants of Premarital Pregnancy and Its Outcome: A Dynamic Analysis of Competing Life Events.

    ERIC Educational Resources Information Center

    Yamaguchi, Kazuo; Kandel, Denise

    1987-01-01

    Examined determinants of occurrence and outcomes of premarital pregnancy. Found cohabitation, being black, poor grades and high peer activity in high school, use of illicit drugs other than marijuana and dropping out to be associated with increased risk of premarital pregnancy. Premarital births were overrepresented among blacks, as were abortions…

  13. Drug Use and Other Determinants of Premarital Pregnancy and Its Outcome: A Dynamic Analysis of Competing Life Events.

    ERIC Educational Resources Information Center

    Yamaguchi, Kazuo; Kandel, Denise

    1987-01-01

    Examined determinants of occurrence and outcomes of premarital pregnancy. Found cohabitation, being black, poor grades and high peer activity in high school, use of illicit drugs other than marijuana and dropping out to be associated with increased risk of premarital pregnancy. Premarital births were overrepresented among blacks, as were abortions…

  14. Geology's Impact on Culture

    NASA Astrophysics Data System (ADS)

    Pizzorusso, Ann

    2017-04-01

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

  15. Human immunodeficiency virus type 1 T-cell tropism is determined by events prior to provirus formation.

    PubMed Central

    Cann, A J; Zack, J A; Go, A S; Arrigo, S J; Koyanagi, Y; Green, P L; Koyanagi, Y; Pang, S; Chen, I S

    1990-01-01

    Different strains of human immunodeficiency virus type 1 (HIV-1) vary in the ability to replicate in cells that bear the HIV-1 receptor, CD4. The mechanism responsible for these cell tropism differences is unknown. We examined different isolates of HIV-1 with regard to replication in specific tumor-derived CD4-positive T-cell lines and normal peripheral blood lymphocytes. To investigate early events in the virus life cycle at low multiplicities of infection, we used a modification of the polymerase chain reaction method. Use of a molecularly cloned primary HIV-1 isolate, HIV-1 JR-CSF, restricted for replication in T-cell lines, demonstrated that little or no viral DNA or RNA was synthesized in nonpermissive cells after infection. However, transfection of proviral DNA resulted in efficient transient virus production from these cells. Therefore, we conclude that at least one block to infection for HIV-1 strains in nonpermissive T cells occurs at a point in entry or uncoating before provirus formation. Images PMID:2398528

  16. An innovative method for automatic determination of time of arrival for Lamb waves excited by impact events

    NASA Astrophysics Data System (ADS)

    Zhu, Junxiao; Parvasi, Seyed Mohammad; Ho, Siu Chun Michael; Patil, Devendra; Ge, Maochen; Li, Hongnan; Song, Gangbing

    2017-05-01

    Lamb waves have great potential as a diagnostic tool in the application of structural health monitoring. Propagation properties of Lamb waves are affected by the state of the structure that the waves are traveling upon. Thus Lamb waves can carry information about the structure as they travel across a structure. However, the dispersive, multimodal and attenuation characteristics of Lamb waves make it difficult to determine the time of arrival of Lamb waves. To deal with these characteristics, an innovative method to automatically determine the time of arrival for impact-induced Lamb waves without human intervention is proposed in this paper. Lead zirconate titanate sensors mounted on the surface of an aluminum plate were used to measure the Lamb waves excited by an impact. The time of arrival was determined based on wavelet decomposition, Hilbert transform and statistics (Grubbs’ test and maximum likelihood estimation). Both of numerical analysis and physical measurements have verified the accuracy of this method for impacts on an aluminum plate.

  17. Oligocene to Recent tectonic history of the Central Solomon intra-arc basin as determined from marine seismic reflection data and compilation of onland geology

    NASA Astrophysics Data System (ADS)

    Cowley, Shane; Mann, Paul; Coffin, M. F.; Shipley, Thomas H.

    2004-10-01

    Systematic analysis of a grid of 3450 km of multichannel seismic reflection lines from the Solomon Islands constrains the late Tertiary sedimentary and tectonic history of the Solomon Island arc and its convergent interaction with the Cretaceous Ontong Java oceanic plateau (OJP). The OJP, the largest oceanic plateau on Earth, subducted beneath the northern edge of the Solomon arc in the late Neogene, but the timing and consequences of this obliquely convergent event and its role in the subduction polarity reversal process remain poorly constrained. The Central Solomon intra-arc basin (CSB), which developed in Oligocene to Recent time above the Solomon arc, provides a valuable record of the tectonic environment prior to and accompanying the OJP convergent event and the subsequent arc polarity reversal. Recognition of regionally extensive stratigraphic sequences—whose ages can be inferred from marine sedimentary sections exposed onland in the Solomon Islands—indicate four distinct tectonic phases affecting the Solomon Island arc. Phase 1: Late Oligocene-Late Miocene rifting of the northeast-facing Solomon Island arc produced basal, normal-fault-controlled, asymmetrical sequences of the CSB; the proto-North Solomon trench was probably much closer to the CSB and is inferred to coincide with the trace of the present-day Kia-Kaipito-Korigole (KKK) fault zone; this protracted period of intra-arc extension shows no evidence for interruption by an early Miocene period of convergent "soft docking" of the Ontong Java Plateau as proposed by previous workers. Phase 2: Late Miocene-Pliocene oblique convergence of the Ontong Java Plateau at the proto-North Solomon trench (KKK fault zone) and folding of the CSB and formation of the Malaita accretionary prism (MAP); the highly oblique and diachronous convergence between the Ontong Java plateau and the Solomon arc terminates intra-arc extension first in the southeast (Russell subbasin of the CSB) during the Late Miocene and

  18. Radiometric Dating in Geology.

    ERIC Educational Resources Information Center

    Pankhurst, R. J.

    1980-01-01

    Described are several aspects and methods of quantitatively measuring geologic time using a constant-rate natural process of radioactive decay. Topics include half lives and decay constants, radiogenic growth, potassium-argon dating, rubidium-strontium dating, and the role of geochronology in support of geological exploration. (DS)

  19. People and Geology.

    ERIC Educational Resources Information Center

    Naturescope, 1987

    1987-01-01

    Provides background information on the many natural resources we extract from the earth's crust, including metals, graphite, and other minerals, as well as fossil fuels. Contains teaching activities such as a geologic scavenger hunt, a geology chronology, and the recycling of aluminum. Includes a reproducible handout for the activity on aluminum.…

  20. 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)

  1. 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.

  2. People and Geology.

    ERIC Educational Resources Information Center

    Naturescope, 1987

    1987-01-01

    Provides background information on the many natural resources we extract from the earth's crust, including metals, graphite, and other minerals, as well as fossil fuels. Contains teaching activities such as a geologic scavenger hunt, a geology chronology, and the recycling of aluminum. Includes a reproducible handout for the activity on aluminum.…

  3. Interpreting Urban Geology.

    ERIC Educational Resources Information Center

    Hannibal, Joseph Timothy; Schmidt, Mark Thomas

    1991-01-01

    Describes field trips to urban locations for geological instruction. The program was developed by the Cleveland Museum of Natural History. Authors claim these field trips have been an effective and enjoyable way of conveying a wide variety of geological information to participants at all levels and backgrounds and have created favorable publicity.…

  4. 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)

  5. 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.

  6. 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.

  7. Radiometric Dating in Geology.

    ERIC Educational Resources Information Center

    Pankhurst, R. J.

    1980-01-01

    Described are several aspects and methods of quantitatively measuring geologic time using a constant-rate natural process of radioactive decay. Topics include half lives and decay constants, radiogenic growth, potassium-argon dating, rubidium-strontium dating, and the role of geochronology in support of geological exploration. (DS)

  8. Geologic remote sensing

    USGS Publications Warehouse

    Goetz, A.F.H.; Rowan, L.C.

    1981-01-01

    Remote-sensing techniques are now being used routinely in geologic interpretation for mineral and energy exploration, plant siting, waste disposal, and the development of models for regional and continental tectonics. New spaceborne methods and associated technologies are being developed to produce data from which geologic information about large areas can be derived much more rapidly than by conventional techniques. Copyright ?? 1981 AAAS.

  9. Women in Early Geology.

    ERIC Educational Resources Information Center

    Elder, Eleanor S.

    1982-01-01

    Biographical sketches are given for several women who made early contributions to the science of geology. A short biography of Inge Lehmann is also included as a more recent example of a woman who has made a notable contribution to the geological field. (Author)

  10. Determining the concentration of individual eruptive events of the CAMP: Distinguishing interflow hiatuses from subterranean alteration and void infilling.

    NASA Astrophysics Data System (ADS)

    Olsen, P. E.; Kent, D. V.; Et-Touhami, M.

    2012-04-01

    -filled cracks in the flow and spread laterally at its base; 3) footprints of small subterranean animals. Features that could identify a significant temporal hiatus between flows absolutely require being produced at the land surface including: 1) terrestrial animal footprints too big to fit in the void; and 2) features requiring sunlight, such as in situ above-ground parts of plants, a root or possibly soil profiles terminating upward at paleohorizonatal surfaces, and possibly stromatolites. Using the above critera, most interflow and cross-cutting features in the Moroccan and eastern North America CAMP prove to be post-emplacement subterranean void fillings and alteration phenomena. There is a residuum of hiatuses that correspond to previously recognized geochemical boundaries between flow sequences or paleosecular magnetic directional groups. This weeding out of spurious hiatuses magnifies the concentration of eruptive events by reducing the inferred duration by one or two orders of magnitudes. For example the more than 30 or so individual basalt flows of the Argana and Central High Atlas basins of Morocco can be reduced to perhaps as few as 4 giant eruptions each lasting less than a hundred years or so. It is the magnitude of these events not the total volume that is most relevant CAMP kill mechanisms.

  11. Geological maps of the European seas - the EMODNET-Geology project.

    NASA Astrophysics Data System (ADS)

    Stevenson, Alan

    2014-05-01

    To support its objectives to achieve Good Environmental Status in Europe's seas by 2020, the European Commission established the European Marine Observation and Data Network (EMODNET) to assemble existing but fragmented and inaccessible marine data and to create interoperable, contiguous and publicly available information layers which encompass whole marine basins. EMODNET is a network of existing and developing European observation systems linked by a data management structure covering all European coastal waters, shelf seas and surrounding ocean basins. The marine departments of the European Geological Surveys form the basis of a partnership that implements the EMODNET-Geology project, part of a suite of EMODNET studies that also cover bathymetry, marine chemistry, marine biology, seabed habitats, physics and human activities in the marine environment. The EMODnet-Geology project will deliver integrated geological map products through the One Geology-Europe portal. EMODNET-Geology will have a distributed map service with each of the work packages delivering a specified layer that include seafloor geology, seabed sediments, mineral resources and geological events such as submarine slides and earthquakes. Further information about the EMODNET project can be found at: http://www.emodnet.eu/

  12. Physicochemical characteristics of structurally determined metabolite-protein and drug-protein binding events with respect to binding specificity

    PubMed Central

    Korkuć, Paula; Walther, Dirk

    2015-01-01

    To better understand and ultimately predict both the metabolic activities as well as the signaling functions of metabolites, a detailed understanding of the physical interactions of metabolites with proteins is highly desirable. Focusing in particular on protein binding specificity vs. promiscuity, we performed a comprehensive analysis of the physicochemical properties of compound-protein binding events as reported in the Protein Data Bank (PDB). We compared the molecular and structural characteristics obtained for metabolites to those of the well-studied interactions of drug compounds with proteins. Promiscuously binding metabolites and drugs are characterized by low molecular weight and high structural flexibility. Unlike reported for drug compounds, low rather than high hydrophobicity appears associated, albeit weakly, with promiscuous binding for the metabolite set investigated in this study. Across several physicochemical properties, drug compounds exhibit characteristic binding propensities that are distinguishable from those associated with metabolites. Prediction of target diversity and compound promiscuity using physicochemical properties was possible at modest accuracy levels only, but was consistently better for drugs than for metabolites. Compound properties capturing structural flexibility and hydrogen-bond formation descriptors proved most informative in PLS-based prediction models. With regard to diversity of enzymatic activities of the respective metabolite target enzymes, the metabolites benzylsuccinate, hypoxanthine, trimethylamine N-oxide, oleoylglycerol, and resorcinol showed very narrow process involvement, while glycine, imidazole, tryptophan, succinate, and glutathione were identified to possess broad enzymatic reaction scopes. Promiscuous metabolites were found to mainly serve as general energy currency compounds, but were identified to also be involved in signaling processes and to appear in diverse organismal systems (digestive and nervous

  13. Determination of snowmaking efficiency on a ski slope from observations and modelling of snowmaking events and seasonal snow accumulation

    NASA Astrophysics Data System (ADS)

    Spandre, Pierre; François, Hugues; Thibert, Emmanuel; Morin, Samuel; George-Marcelpoil, Emmanuelle

    2017-04-01

    The production of Machine Made (MM) snow is now generalized in ski resorts and represents the most common method of adaptation for mitigating the impact of a lack of snow on skiing. Most investigations of correlations between snow conditions and the ski industry's economy focus on the production of MM snow though not one of these has taken into account the efficiency of the snowmaking process. The present study consists of observations of snow conditions (depth and mass) using a Differential GPS method and snow density coring, following snowmaking events and seasonal snow accumulation in Les Deux Alpes ski resort (French Alps). A detailed physically based snowpack model accounting for grooming and snowmaking was used to compute the seasonal evolution of the snowpack and compared to the observations. Our results show that approximately 30 % of the water mass can be recovered as MM snow within 10 m from the center of a MM snow pile after production and 50 % within 20 m. Observations and simulations on the ski slope were relatively consistent with 60 % (±10 %) of the water mass used for snowmaking within the limits of the ski slope. Losses due to thermodynamic effects were estimated in the current case example to be less than 10 % of the total water mass. These results suggest that even in ideal conditions for production a significant fraction of the water used for snowmaking can not be found as MM snow within the limits of the ski slope with most of the missing fraction of water. This is due to site dependent characteristics (e.g. meteorological conditions, topography).

  14. Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory; a method supplement for the determination of Fipronil and degradates in water by gas chromatography/mass spectrometry

    USGS Publications Warehouse

    Madsen, James F.; Sandstrom, Mark W.; Zaugg, Steven D.

    2002-01-01

    A method for the isolation and detemrination of fipronil and four of its degradates has been developed. This method adapts an analytical method created by the U.S. Geological Survey National Water Quality Laboratory in 1995 for the determination of a broad range of high-use pesticides typically found in filtered natural-water samples. In 2000, fipronil and four of its degradates were extracted, analyzed, and validated using this method. The recoveries for these five compounds in reagent-water samples fortified at 1 microgram per liter (ug/L) avereraged 98 percent. Initial method detection limits averaged 0.0029 ug/L. The performance of these five new compounds is consistent with the performance of the compounds in the initial method, making it possible to include them in addition to the other 41 pesticides and pesticide degradates in the original method.

  15. Reconnaissance for determining effects of land use and surficial geology on concentrations of selected elements on streambed materials from the coal-mining region, southwestern Indiana, October 1979 to March 1980

    USGS Publications Warehouse

    Wilber, W.G.; Boje, Rita R.

    1982-01-01

    Streambed materials were collected in October 1979 from 69 watersheds in Southwest Indiana having predominantly forested, agricultural, reclaimed, and unreclaimed mined land use to determine whether concentrations of sorbed and acid-soluble metals and trace elements were affected by land use and surficial geology. Analysis of variance indicated that 10% or more of the total variation in aluminum, arsenic, cobalt, iron, nickel, selenium, and zinc concentrations on streambed materials was accounted for by differences in land use. Concentrations of aluminum, cobalt, iron, nickel, selenium, and zinc on streambed materials smaller than 0.062-millimeter from mined watersheds were significantly greater than the concentrations of these elements on streambed materials from agricultural and forested watersheds. The greater concentrations of these elements on streambed materials are due to (1) their concentrations in mine drainage and their subsequent absorption and (or) copecipitation with the oxides and hydroxides of aluminum and iron and (2) their concentrations in coal and pyritic material in streambed materials. (USGS)

  16. Spacecraft Solar Particle Event (SPE) Shielding: Shielding Effectiveness as a Function of SPE Model as Determined with the FLUKA Radiation Transport Code

    NASA Astrophysics Data System (ADS)

    Koontz, S. L.; Atwell, W. A.; Reddell, B.; Rojdev, K.

    2010-12-01

    In the this paper, we report the results of modeling and simulation studies in which the radiation transport code FLUKA (FLUktuierende KAskade) is used to determine the changes in total ionizing dose (TID) and single-event effect (SEE) environments behind aluminum, polyethylene, carbon, and titanium shielding masses when the assumed form (i.e., Band or Exponential) of the solar particle event (SPE) kinetic energy spectra is changed. FLUKA simulations are fully three dimensional with an isotropic particle flux incident on a concentric spherical shell shielding mass and detector structure. FLUKA is a fully integrated and extensively verified Monte Carlo simulation package for the interaction and transport of high-energy particles and nuclei in matter. The effects are reported of both energetic primary protons penetrating the shield mass and secondary particle showers caused by energetic primary protons colliding with shielding mass nuclei. SPE heavy ion spectra are not addressed. Our results, in agreement with previous studies, show that use of the Exponential form of the event spectra can seriously underestimate spacecraft SPE TID and SEE environments in some, but not all, shielding mass cases. The SPE spectra investigated are taken from four specific SPEs that produced ground-level events (GLEs) during solar cycle 23 (1997-2008). GLEs are produced by highly energetic solar particle events (ESP), i.e., those that contain significant fluences of 700 MeV to 10 GeV protons. Highly energetic SPEs are implicated in increased rates of spacecraft anomalies and spacecraft failures. High-energy protons interact with Earth’s atmosphere via nuclear reaction to produce secondary particles, some of which are neutrons that can be detected at the Earth’s surface by the global neutron monitor network. GLEs are one part of the overall SPE resulting from a particular solar flare or coronal mass ejection event on the sun. The ESP part of the particle event, detected by spacecraft

  17. Use of Ga for mass bias correction for the accurate determination of copper isotope ratio in the NIST SRM 3114 Cu standard and geological samples by MC-ICP MS

    NASA Astrophysics Data System (ADS)

    Zhang, T.; Zhou, L.; Tong, S.

    2015-12-01

    The absolute determination of the Cu isotope ratio in NIST SRM 3114 based on a regression mass bias correction model is performed for the first time with NIST SRM 944 Ga as the calibrant. A value of 0.4471±0.0013 (2SD, n=37) for the 65Cu/63Cu ratio was obtained with a value of +0.18±0.04 ‰ (2SD, n=5) for δ65Cu relative to NIST 976.The availability of the NIST SRM 3114 material, now with the absolute value of the 65Cu/63Cu ratio and a δ65Cu value relative to NIST 976 makes it suitable as a new candidate reference material for Cu isotope studies. In addition, a protocol is described for the accurate and precise determination of δ65Cu values of geological reference materials. Purification of Cu from the sample matrix was performed using the AG MP-1M Bio-Rad resin. The column recovery for geological samples was found to be 100±2% (2SD, n=15).A modified method of standard-sample bracketing with internal normalization for mass bias correction was employed by adding natural Ga to both the sample and the solution of NIST SRM 3114, which was used as the bracketing standard. An absolute value of 0.4471±0.0013 (2SD, n=37) for 65Cu/63Cu quantified in this study was used to calibrate the 69Ga/71Ga ratio in the two adjacent bracketing standards of SRM 3114,their average value of 69Ga/71Ga was then used to correct the 65Cu/63Cu ratio in the sample. Measured δ65Cu values of 0.18±0.04‰ (2SD, n=20),0.13±0.04‰ (2SD, n=9),0.08±0.03‰ (2SD, n=6),0.01±0.06‰(2SD, n=4) and 0.26±0.04‰ (2SD, n=7) were obtained for five geological reference materials of BCR-2,BHVO-2,AGV-2,BIR-1a,and GSP-2,respectively,in agreement with values obtained in previous studies.

  18. Meteorites, the Moon and the History of Geology.

    ERIC Educational Resources Information Center

    Marvin, Ursula B.

    1986-01-01

    Traces the historical events that linked geology with the planetary sciences. Reviews the origins of meteorities as a modern science and highlights the advances made in this area. Discusses lunar related theories and research. (ML)

  19. Meteorites, the Moon and the History of Geology.

    ERIC Educational Resources Information Center

    Marvin, Ursula B.

    1986-01-01

    Traces the historical events that linked geology with the planetary sciences. Reviews the origins of meteorities as a modern science and highlights the advances made in this area. Discusses lunar related theories and research. (ML)

  20. Determination of depths to centroids of three-dimensional sources of potential-field anomalies with examples from environmental and geologic applications

    NASA Astrophysics Data System (ADS)

    Ravat, D.; Taylor, Patrick T.

    1998-09-01

    A method is developed for determining the depth to the centroid (the geometric center) of `semi-compact' sources. The method, called the anomaly attenuation rate (AAR) method, involves computing radial averages of AARs with increasing distances from a range of assumed source centers. For well-isolated magnetic anomalies from `semi-compact' sources, the theoretical AARs range from ˜2 (close to the sources) to ˜3 (in the far-field region); the corresponding theoretical range of AARs for gravity anomalies is ˜1 to ˜2. When the estimated source centroid is incorrect, the AARs either exceed or fall short of the theoretical values. The levelling-off of the far-field AARs near their theoretical maximum values indicates the upper (deeper) bound of the centroid location. Similarly, near-field AARs lower than the theoretical minimum indicate the lower (shallower) bound of the centroid location. It is not always possible to determine usable upper and lower bounds of the centroids because the method depends on characteristics of sources/anomalies and the noise level of the data. For the environmental magnetic examples considered in this study, the determined deeper bounds were within 4% of the true centroid-to-observation distance. For the case of the gravity anomaly from the Bloomfield Pluton, Missouri, USA, determination of only the shallower bound of the centroid location (˜7 km) was possible. This estimate agrees closely with the centroid of a previously determined three-dimensional model of the Bloomfield Pluton. For satellite magnetic anomalies, the method is appropriate only for high-amplitude, near-circular anomalies due to the inherent low signal-to-noise ratio of satellite magnetic anomalies. Model studies indicate that the AAR method is able to place depths within ±20-30 km of actual center locations from a 400-km observation altitude. Thus, the method may be able to discriminate between upper crustal, lower crustal, and mantle magnetic sources. The results

  1. The Geologic Time Spiral - A Path to the Past

    USGS Publications Warehouse

    Graham, Joseph; Newman, William; Stacy, John

    2008-01-01

    The Earth is very old - 4.5 billion years or more according to scientific estimates. Most of the evidence for an ancient Earth is contained in the rocks that form the Earth's crust. The rock layers themselves - like pages in a long and complicated history - record the events of the past, and buried within them are the remains of life - the plants and animals that evolved from organic structures that existed 3 billion years ago. Also contained in rocks once molten are radioactive elements whose isotopes provide Earth with an atomic clock. Within these rocks, 'parent' isotopes decay at a predictable rate to form 'daughter' isotopes. By determining the relative amounts of parent and daughter isotopes, the age of these rocks can be calculated. Thus, the scientific evidence from rock layers, from fossils, and from the ages of rocks as measured by atomic clocks attests to a very old Earth. See USGS Fact Sheet 2007-3015 at http://pubs.usgs.gov/fs/2007/3015/ for ages of geologic time periods. Ages in the spiral have been rounded from the age estimates in the Fact Sheet. B.Y., billion years; M.Y., million years. For more information, see the booklet on Geologic Time at http://pubs.usgs.gov/gip/geotime/. The Geologic Time Spiral poster is available for purchase from the USGS Store.

  2. Inductively coupled plasma atomic emission spectroscopic determination of rare earth elements in geological samples after preconcentration by countercurrent chromatography—I

    NASA Astrophysics Data System (ADS)

    Pukhovskaya, V. M.; Maryutina, T. A.; Grebneva, O. N.; Kuz'min, N. M.; Spivakov, B. Ya.

    1993-09-01

    Countercurrent chromatography (CCC) was applied to group pre-separation of rare earth elements (REE) in rocks. A 0.5 mol/l solution of di-2-ethylhexylphosphoric acid (D2EHPA) in n-decane as stationary phase, and aqueous HC1 solution as mobile phase were used. Experimental conditions were found for quantitative separation of REE from the rock constituents that interfere with their inductively coupled plasma atomic emission spectrometry (ICP-AES) determination. The complete preseparation procedure takes 40 min at a mobile phase pumping rate of 2 ml/min. Interelement and off-peak background corrections were applied to compensate for the contributions of mutual spectral interferences to the analyte line and background intensities. Standard reference rock materials and samples of different composition with well known REE contents were analysed. The data obtained are in good agreement with certified and previously determined values, except for "heavy" REE such as Tm, Yb and Lu.

  3. Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory; determination of low-level silver by graphite furnace atomic absorption spectrophotometry

    USGS Publications Warehouse

    Damrau, D.L.

    1993-01-01

    Increased awareness of the quality of water in the United States has led to the development of a method for determining low levels (0.2-5.0 microg/L) of silver in water samples. Use of graphite furnace atomic absorption spectrophotometry provides a sensitive, precise, and accurate method for determining low-level silver in samples of low ionic-strength water, precipitation water, and natural water. The minimum detection limit determined for low-level silver is 0.2 microg/L. Precision data were collected on natural-water samples and SRWS (Standard Reference Water Samples). The overall percent relative standard deviation for natural-water samples with silver concentrations more than 0.2 microg/L was less than 40 percent throughout the analytical range. For the SRWS with concentrations more than 0.2 microg/L, the overall percent relative standard deviation was less than 25 percent throughout the analytical range. The accuracy of the results was determined by spiking 6 natural-water samples with different known concentrations of the silver standard. The recoveries ranged from 61 to 119 percent at the 0.5-microg/L spike level. At the 1.25-microg/L spike level, the recoveries ranged from 92 to 106 percent. For the high spike level at 3.0 microg/L, the recoveries ranged from 65 to 113 percent. The measured concentrations of silver obtained from known samples were within the Branch of Quality Assurance accepted limits of 1 1/2 standard deviations on the basis of the SRWS program for Inter-Laboratory studies.

  4. Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory; preparation procedure for aquatic biological material determined for trace metals

    USGS Publications Warehouse

    Hoffman, Gerald L.

    1996-01-01

    A method for the chemical preparation of tissue samples that are subsequently analyzed for 22 trace metals is described. The tissue-preparation procedure was tested with three National Institute of Standards and Technology biological standard reference materials and two National Water Quality Laboratory homogenized biological materials. A low-temperature (85 degrees Celsius) nitric acid digestion followed by the careful addition of hydrogen peroxide (30-percent solution) is used to decompose the biological material. The solutions are evaporated to incipient dryness, reconstituted with 5 percent nitric acid, and filtered. After filtration the solutions were diluted to a known volume and analyzed by inductively coupled plasma-mass spectrometry (ICP-MS), inductively coupled plasma-atomic emission spectrometry (ICP-AES), and cold vapor-atomic absorption spectrophotometry (CV-AAS). Many of the metals were determined by both ICP-MS and ICP-AES. This report does not provide a detailed description of the instrumental procedures and conditions used with the three types of instrumentation for the quantitation of trace metals determined in this study. Statistical data regarding recovery, accuracy, and precision for individual trace metals determined in the biological material tested are summarized.

  5. Investigation of novel rapidly synergistic cloud point extraction pattern for bismuth in water and geological samples coupling with flame atomic absorption spectrometry determination.

    PubMed

    Wen, Xiaodong; Zhao, Yu; Deng, Qingwen; Ji, Shoulian; Zhao, Xia; Guo, Jie

    2012-04-01

    Rapidly synergistic cloud point extraction (RS-CPE) greatly simplified and accelerated the procedure of traditional cloud point extraction (CPE). In order to expand the application of RS-CPE, this work was carried out after the establishment of the improved extraction technique. The new established extraction method was firstly applied for bismuth extraction and determination coupled with flame atomic absorption spectrometry (FAAS) in this work. The improved RS-CPE was accomplished in the room temperature in 1 min. Non-ionic surfactant Triton X-100 (TX-100) was used as extractant. Octanol worked as cloud point revulsant and synergic reagent. TX-100 has a relatively high cloud point temperature (CPT), which limited its application in CPE. In this work, TX-100 accomplished the RS-CPE procedure in room temperature successfully. The factors influencing RS-CPE, such as concentrations of reagents, pH, conditions of phase separation, effect of environmental temperatures, salt effect and instrumental conditions, were studied systematically. Under the optimal conditions, the limit of detection (LOD) for bismuth was 4.0 μg L(-1), with sensitivity enhancement factor (EF) of 43. The proposed method greatly improved the sensitivity of FAAS for the determination of bismuth and was applied to the determination of trace bismuth in real and certified samples with satisfactory analytical results. The proposed method was rapid, simple, and sensitive.

  6. Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory; determination of the total phosphorus by a Kjeldahl digestion method and an automated colorimetric finish that includes dialysis

    USGS Publications Warehouse

    Patton, Charles J.; Truitt, Earl P.

    1992-01-01

    A method to determine total phosphorus (TP) in the same digests prepared for total Kjeldahl nitrogen (TKN) determinations is desribed. The batch, high-temperature (block digester), HG(II)-catalyzed digestion step is similar to U.S. Geological Survey methods I-2552-85/I-4552-85 and U.S. Environmental Protection Agency method 365.4 except that sample and reagent volumes are halved. Prepared digests are desolvated at 220 degrees Celsius and digested at 370 degrees Celsius in separate block digesters set at these temperatures, rather than in a single, temperature-programmed block digester. This approach is used in the method escribed here, which permits 40 calibrants, reference waters, and smaples to be digested and resolvated in about an hour. Orthophosphate ions originally present in samples, along with those released during the digestion step, are determined colorimetrically at a rate of 90 tests per hour by an automated version of the phosphoantimonylmolybdenum blue procedure. About 100 microliters of digest are required per determination. The upper concentration limit is 2 milligrams per liter (mg/L) with a method detection limt of 0.01 mg/L. Repeatability for a sample containing approximately 1.6 mg/L of TP in a high suspended-solids matrix is 0.7 percent. Between-day precision for the same sample is 5.0 percent. A dialyzer in the air-segmented continuous flow analyzer provides on-line digest cleanup, eliminated particulates that otherwise would interfere in the colorimetric finish. An single-channel analyzer can process the resolvated digests from two pairs of block digesters each hour. Paired t-test analysis of TP concentrations for approximately 1,600 samples determined by the new method (U.S. Geologial Survey methods I-2610-91 and I-4610-91) and the old method (U.S. Geological Survey methods I-2600-85 and I-4600-85) revealed positive bias in the former of 0.02 to 0.04 mg/L for surface-water samples in agreement with previous studies. Concentrations of total

  7. Volcanic and geologic database projects of the Geological Survey of Japan (Invited)

    NASA Astrophysics Data System (ADS)

    Takarada, S.; Nakano, S.; Hoshizumi, H.; Itoh, J.; Urai, M.; Nishiki, K.

    2009-12-01

    Geological Survey of Japan (GSJ) is presently implementing the GEO-DB project, which aims to integrate all kinds of geological information in GSJ. GSJ published more than 50 CD-ROM series and established more than 20 databases at the Research Information Database (RIO-DB) of the National Institute of Advanced Industrial Science and Technology (AIST). Presently, four volcanic databases are open to the public: (1) Quaternary volcano database (RIO-DB), (2) Active volcano database (RIO-DB), and (3) ASTER satellite image database of major volcanoes. The Quaternary volcano database contains information such as volcanic type, history, age and pictures of more than 300 Quaternary volcanoes in Japan. More detailed volcanic information will be added to the database in the near future. The active volcano database contains information of active volcanoes in Japan such as the catalog of eruptive events during the last 10,000 years and geological maps of active volcanoes. The ASTER satellite image database provides sequential ASTER satellite image datasets of major volcanoes in the world. Collaboration between Quaternary and active volcano databases and the VOGRIPA project is the next important activity at the Geological Survey of Japan. The Geological Survey of Japan introduced the Integrated Geological Map Database (GeoMapDB) in 2006. The GeoMapDB is based on a WebGIS technology, which makes it possible to browse, overlay and search geological maps online. The database contains geological maps with scales ranging from 1:2 million to 1:25,000. Links to aforementioned volcanic database and active fault database in RIO-DB are also available. OneGeology is an international initiative of the geological surveys of the world and a flagship project of the ‘International Year of Planet Earth’. It aims to create dynamic geological map of the world available at the world wide web. Geological Surveys from 109 countries of the world are participating in this project. The Geological

  8. Determination of trace elements in calcium rich carbonate rocks by Wavelength Dispersive X-ray Fluorescence Spectrometry for environmental and geological studies.

    PubMed

    Cherkashina, T Yu; Shtel'makh, S I; Pashkova, G V

    2017-09-23

    A simple, rapid and non destructive Wavelength Dispersive X-ray Fluorescence Spectrometry (WDXRFS) was developed for the determination of trace elements such as V, Cr, Co, Ni, Cu, Zn, Pb, Ba, La, Ce, Nd, Rb, Sr, Y, Zr, and Nb in carbonate rocks with high calcium content. Samples of marble, limestone, fluorite ore and carbonatite-like rocks were chosen as objects under investigation. These samples have wide ranges of major and trace element contents, and high concentration of calcite (70-98%) in calcium rich carbonates. The sample mass required for infinite thickness was calculated for each element. In order to determine V, Cr, Co, Ni, Cu, Zn, Ba, La, Nd, Ce, sample weighting 1g was pressed with a pressure of 100kN. For the determination of Rb, Sr, Y, Zr, Nb, Pb, the sample mass was increased up to 5g. The calibration curves were constructed by employing the International Certified reference materials (ICRMs) and in-house standard reference materials (HSRMs) of various types of rocks and sediments, and the matrix effects were taken into account using the influence coefficients (α-correction equations). Analytical figures of merit have also been assessed. The calculated values of the instrumental limit of the detection were within the interval from 0.5 to 4.0mgkg(-1). The repeatability and reproducibility were found to be satisfactory with the relative standard deviations lower than 5%. The accuracy was evaluated by the analysis of two reference materials and the comparison with the ICP-MS results. A good agreement was achieved between the reference and measured values with recoveries ranging from 85% to 115%. The relative disagreements between the XRF and ICP-MS results were less than 10%. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Method of Analysis by the U.S. Geological Survey California District Sacramento Laboratory?Determination of Trihalomethane Formation Potential, Method Validation, and Quality-Control Practices

    USGS Publications Warehouse

    Crepeau, Kathryn L.; Fram, Miranda S.; Bush, Noel

    2004-01-01

    An analytical method for the determination of the trihalomethane formation potential of water samples has been developed. The trihalomethane formation potential is measured by dosing samples with chlorine under specified conditions of pH, temperature, incubation time, darkness, and residual-free chlorine, and then analyzing the resulting trihalomethanes by purge and trap/gas chromatography equipped with an electron capture detector. Detailed explanations of the method and quality-control practices are provided. Method validation experiments showed that the trihalomethane formation potential varies as a function of time between sample collection and analysis, residual-free chlorine concentration, method of sample dilution, and the concentration of bromide in the sample.

  10. Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory; determination of inorganic and organic constituents in water and fluvial sediments

    USGS Publications Warehouse

    Fishman, M. J.

    1993-01-01

    Methods to be used to analyze samples of water, suspended sediment and bottom material for their content of inorganic and organic constituents are presented. Technology continually changes, and so this laboratory manual includes new and revised methods for determining the concentration of dissolved constituents in water, whole water recoverable constituents in water-suspended sediment samples, and recoverable concentration of constit- uents in bottom material. For each method, the general topics covered are the application, the principle of the method, interferences, the apparatus and reagents required, a detailed description of the analytical procedure, reporting results, units and significant figures, and analytical precision data. Included in this manual are 30 methods.

  11. Geological hazard monitoring system in Georgia

    NASA Astrophysics Data System (ADS)

    Gaprindashvili, George

    2017-04-01

    Georgia belongs to one of world's most complex mountainous regions according to the scale and frequency of Geological processes and damage caused to population, farmlands, and Infrastructure facilities. Geological hazards (landslide, debrisflow/mudflow, rockfall, erosion and etc.) are affecting many populated areas, agricultural fields, roads, oil and gas pipes, high-voltage electric power transmission towers, hydraulic structures, and tourist complexes. Landslides occur almost in all geomorphological zones, resulting in wide differentiation in the failure types and mechanisms and in the size-frequency distribution. In Georgia, geological hazards triggered by: 1. Activation of highly intense earthquakes; 2. Meteorological events provoking the disaster processes on the background of global climatic change; 3. Large-scale Human impact on the environment. The prediction and monitoring of Geological Hazards is a very wide theme, which involves different researchers from different spheres. Geological hazard monitoring is essential to prevent and mitigate these hazards. In past years in Georgia several monitoring system, such as Ground-based geodetic techniques, Debrisflow Early Warning System (EWS) were installed on high sensitive landslide and debrisflow areas. This work presents description of Geological hazard monitoring system in Georgia.

  12. Fundamentals of Structural Geology

    NASA Astrophysics Data System (ADS)

    Pollard, David D.; Fletcher, Raymond C.

    2005-09-01

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

  13. Determining the source of strong LF/VLF TIPP events: Implications for association with NPBPs and NNBPs

    NASA Astrophysics Data System (ADS)

    Zuelsdorf, R. S.; Franz, R. C.; Strangeway, R. J.; Russell, C. T.

    2000-08-01

    Transionospheric pulse pairs (TIPPs) as detected by the Blackbeard VHF radio instrument onboard the ALEXIS satellite have been shown to correlate with pulses detected by stations in the National Lightning Detection Network (NLDN). The short peak-to-zero time of these NLDN-detected pulses (<10 μs) are indicative of interior cloud processes, as opposed to the longer pulses associated with cloud-to-ground discharges. TIPPs are most probably generated by the same discharge responsible for narrow bipolar pulses (NBPs), which have been detected on the ground but are also believed to be generated entirely inside the cloud. Here we report on five TIPPs detected by Blackbeard that are correlated with cloud-generated pulses detected by multiple stations in the NLDN during powerful storms. Previously, a maximum of two stations at a time showed such a correlation. Given the greater area of detection, these pulses radiate more powerfully in the LF/VLF frequencies than those previously detected as TIPPs by Blackbeard. We are able to place the sources of the TIPPs in Hurricane Fausto off the coast of Mexico, and in a remnant of the same storm eight days later over Texas. The heights of the sources are higher than those previously determined for TIPPs. The higher altitudes and the greater power of the TIPP-correlating signals may be related to the intensity of the storms. Two of these five TIPPs were also correlated with the ground detection of HF signals, and the TIPPs and HF signals were determined to originate from the same source region. These HF signals are similar to those previously recorded with the field change signature of narrow positive bipolar pulses (NPBPs), but we find that both polarities are detected, four out of the five being negative. This indicates that TIPPs correlate with narrow negative bipolar pulses (NNBPs) as well as NPBPs. The detection of NNBPs, which has previously been much rarer than NPBPs, may also be related to the intensity of the storms and the

  14. Direct ICP-MS determination of trace and ultratrace elements in geological materials after decomposition in a microwave oven. I. Quantitation of Y, Th, U and the lanthanides.

    PubMed

    Gupta, J G; Bertrand, N B

    1995-11-01

    A microwave digestion technique using a mixture of HF + HNO(3) + HCl + H(3)BO(3) was found to be effective for the rapid dissolution of various silicate rock and sediment reference samples. From the solutions thus prepared, it was possible to determine quantitatively trace and ultratrace amounts of yttrium, thorium, uranium and the lanthanides by inductively coupled plasma-mass spectrometry (ICP-MS) without any separation of matrix elements or preconcentration. In the ICP-MS determinations, oxide and non-spectral interferences on individual masses of the rare earth element ions were corrected by the method of algebraic approach of elimination and dilution, respectively, and measurement drift was controlled by ruthenium and rhenium internal standards. The method yielded excellent results comparable with "recommended", "consensus" and "working" values of the literature for the specified elements on various well-known international reference materials such as andesite (AGV-1), basalts (BCR-1, BHVO-1, BIR-1 and BE-N), granites (G-2 and NIM-G), syenite (SY-2), gabbro (MRG-1), diabase (W-2 and DNC-1), marine mud (MAG-1), river sediment (NBS 1645), lake sediments (LKSD-1-LKSD-4) and stream sediment (GSD-1, GSD-5, GSD-6 and STSD-1-STSD-4)). New values for Er, Gd, Ho, Pr and Tm in LKSD-1-LKSD-4 and STSD-1-STSD-4, and Er, Ho, Lu, Nd, Pr, Tb, Tm and Yb in NBS 1645 are first reported in this work.

  15. Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory; determination of chromium in water by graphite furnace atomic absorption spectrophotometry

    USGS Publications Warehouse

    McLain, B.J.

    1993-01-01

    Graphite furnace atomic absorption spectrophotometry is a sensitive, precise, and accurate method for the determination of chromium in natural water samples. The detection limit for this analytical method is 0.4 microg/L with a working linear limit of 25.0 microg/L. The precision at the detection limit ranges from 20 to 57 percent relative standard deviation (RSD) with an improvement to 4.6 percent RSD for concentrations more than 3 microg/L. Accuracy of this method was determined for a variety of reference standards that was representative of the analytical range. The results were within the established standard deviations. Samples were spiked with known concentrations of chromium with recoveries ranging from 84 to 122 percent. In addition, a comparison of data between graphite furnace atomic absorption spectrophotometry and direct-current plasma atomic emission spectrometry resulted in suitable agreement between the two methods, with an average deviation of +/- 2.0 microg/L throughout the analytical range.

  16. Interference effect of iron on the determination of gold in geological samples using the vapor generation technique and preconcentration in a graphite furnace.

    PubMed

    Ertaş, Gülay; Ataman, O Yavuz

    2006-04-01

    A vapor generation procedure for the production of volatile species of Au was studied using electrothermal atomic absorption spectrometry (ETAAS). The interference effects of iron in solution and in the gas phase in a quartz T-tube were studied for the first time in detail. A dual vapor generation system was used for a single heated quartz tube atomizer, so that it was possible to study interferences and classify them regarding their origins. Results show that both gas-phase and liquid-phase interferences are present. It was also concluded that since the total interference effect causes the Au signal to be lower as compared to only the presence of gas-phase interactions in the experiment, the net liquid-phase interference from Fe should be suppressed. The method described in this study was used for the determination of gold in an ore reference material, Carlin Ore Mine, for the purpose of demonstrating the ability of the reported method to determine Au without any extraction procedure.

  17. Determination of rare earth elements in geological samples by inductively coupled plasma atomic emission spectrometry with flow injection liquid-liquid extraction.

    PubMed

    Xu, Zhifang; Liu, Congqiang; Zhang, Hongxiang; Ma, Yingjun; Lin, Soulin

    2003-12-01

    A direct sampling with organic solvent extracts for simultaneous multi-element determination implemented with inductively coupled plasma atomic emission spectrometry (ICP-AES) associated with a flow injection liquid-liquid extraction (FI-LLE) sample preconcentration method was studied. The "robustness" of the plasma discharge with tributyl phosphate (TBP) loading was diagnosed by using the Mg II 279.55 nm and Mg I 285.21 nm lines intensity ratio. A FI-LLE preconcentration system for rare earth elements (REEs)-nitrate-TBP was established by using a laboratory-designed phase separator. For these elements, an average sensitivity enhancement factor of 64 was obtained with respect to ICP-AES sampling with aqueous solutions. The precision of the method was characterized by a relative standard deviation (%RSD) of 1.8 - 5.2%. A throughput of 27 samples per hour can be achieved with an organic solvent consumption of less than 200 microl per determination. Good results were obtained for the analysis of standard reference materials.

  18. Geologic Mapping of the Meridiani Region, Mars

    NASA Technical Reports Server (NTRS)

    Hynek, B. M.

    2008-01-01

    The light toned bedrock that has been observed at the Mars Exploration Rover Opportunity landing site is an upper layer in a sequence >600 m thick in places. These outcrops contain mineral and textural signatures that require interaction of, and possibly formation from, water. Many distinct layers are visible in the remote sensing data (e.g. Figure 1) and no work has ever characterized the full set of these materials that cover an area >3 105 km2 spanning 20 of longitude. Thus, whatever water-related process( es?) altered, and possibly formed, the rocks at the Opportunity landing site extended over a vast region of Mars. Yet many questions remain to be answered, such as: (1) in what capacity did water form and alter the deposits?, (2) what are the temporal and spatial relations with other major events known from ancient Mars?, and (3) would this type of environment have been conducive to the development of life? To address these questions we are completing a detailed geologic, stratigraphic, and thermophysical properties study of this widespread terrain. Specifically, we are drafting a 1:2M-scale geological map covering the full extent of these water-related deposits. In tandem with the mapping, Hynek and Phillips [1] have conducted a preliminary stratigraphic analysis of the stack of materials. After mapping is complete, we will study the thermophysical properties of the varied layers to derive possible compositional information of the materials. These tasks serve several purposes including gaining an understanding of the complex nature of these materials, their potential source region(s), and their timing of emplacement. All of these efforts are necessary to place the observations by the Opportunity Rover in a broader context and prepare for potential future landed missions to the region. Understanding the large-scale paleohydrology of Mars is central to NASA s goals and vital for determining if life ever arose on the planet.

  19. Quaternary Geologic Map of Connecticut and Long Island Sound Basin

    USGS Publications Warehouse

    Stone, Janet Radway; Schafer, John P.; London, Elizabeth Haley; DiGiacomo-Cohen, Mary L.; Lewis, Ralph S.; Thompson, Woodrow B.

    2005-01-01

    The Quaternary geologic map (sheet 1) and explanatory figures and cross sections (sheet 2) portray the geologic features formed in Connecticut during the Quaternary Period, which includes the Pleistocene (glacial) and Holocene (postglacial) Epochs. The Quaternary Period has been a time of development of many details of the landscape and of all the surficial deposits. At least twice in the late Pleistocene, continental ice sheets swept across Connecticut. Their effects are of pervasive importance to the present occupants of the land. The Quaternary geologic map illustrates the geologic history and the distribution of depositional environments during the emplacement of glacial and postglacial surficial deposits and the landforms resulting from those events.

  20. Geologic Map of Nevada

    USGS Publications Warehouse

    Crafford, A. Elizabeth Jones

    2007-01-01

    The purpose of the Geologic Map of Nevada is to provide an integrated set of digital geologic information that can be used for regional geologic and rigorous spatial analysis. Two components of this map represent new information that has not been published in this form before. The new geology layer was created by merging into a single file individual digital Nevada county geologic maps (Hess and Johnson, 1997), published at a scale of 1:250,000. A new regional interpretation was created to unify all of the different county rock units, and then appropriate edits and modifications were made to the file to reflect additional geologic information and more current geologic interpretations. All possible sources of information were not utilized in the scope of this project, but rather the goal was to create a consistent Statewide 1:250,000-scale map that would facilitate regional geologic interpretation and be a foundation for future spatial analyses of digital data. Secondly, a new database of conodont biostratigraphic data compiled and analyzed by Anita Harris is also incorporated into the map. Information about many, but not all, of these conodont samples have been published separately elsewhere over the years, but they have not been presented together in a single digital database. Other previously published data layers are used in this map to enhance the usefulness of the geologic information. These layers include mineral deposit locations, oil well locations, and cartographic layers such as county boundaries, roads, towns, cities, rivers, water bodies, township, range and section grids, quadrangle grids, and topography. A summary of these components is given below, and complete descriptions of each layer are provided in the digital metadata.

  1. 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)

  2. 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)

  3. 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.

  4. Geology of caves

    USGS Publications Warehouse

    Morgan, I.M.

    1991-01-01

    A cave is a natural opening in the ground extending beyond the zone of light and large enough to permit the entry of man. Occurring in a wide variety of rock types and caused by widely differing geological processes, caves range in size from single small rooms to intercorinecting passages many miles long. The scientific study of caves is called speleology (from the Greek words spelaion for cave and logos for study). It is a composite science based on geology, hydrology, biology, and archaeology, and thus holds special interest for earth scientists of the U.S. Geological Survey.

  5. Glossary of Geology

    NASA Astrophysics Data System (ADS)

    Jackson, Julia A.

    The Glossary has expanded coverage particularly in such active fields as carbonate sedimentology, environmental geology and geophysics, GIS, GPS, hydrology and hydraulics, marine and coastal geology, organic geochemistry, paleoecology, seismology, stratigraphic nomenclature, speleology and karst, and structural geology and tectonics. Many definitions provide a syllabification guide and background information. Thus a reader will learn the difference between look-alike pairs, such as sylvanite (a mineral) and sylvinite (a rock); the origin of terms; the meaning of abbreviations and acronyms common in the geosciences vocabulary; the dates many terms were first used; the meaning of certain prefixes; and the preferred term of two or more synonyms.

  6. Computer image processing: Geologic applications

    NASA Technical Reports Server (NTRS)

    Abrams, M. J.

    1978-01-01

    Computer image processing of digital data was performed to support several geological studies. The specific goals were to: (1) relate the mineral content to the spectral reflectance of certain geologic materials, (2) determine the influence of environmental factors, such as atmosphere and vegetation, and (3) improve image processing techniques. For detection of spectral differences related to mineralogy, the technique of band ratioing was found to be the most useful. The influence of atmospheric scattering and methods to correct for the scattering were also studied. Two techniques were used to correct for atmospheric effects: (1) dark object subtraction, (2) normalization of use of ground spectral measurements. Of the two, the first technique proved to be the most successful for removing the effects of atmospheric scattering. A digital mosaic was produced from two side-lapping LANDSAT frames. The advantages were that the same enhancement algorithm can be applied to both frames, and there is no seam where the two images are joined.

  7. Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory; determination of antimony by automated-hydride atomic absorption spectrophotometry

    USGS Publications Warehouse

    Brown, G.E.; McLain, B.J.

    1994-01-01

    The analysis of natural-water samples for antimony by automated-hydride atomic absorption spectrophotometry is described. Samples are prepared for analysis by addition of potassium and hydrochloric acid followed by an autoclave digestion. After the digestion, potassium iodide and sodium borohydride are added automatically. Antimony hydride (stibine) gas is generated, then swept into a heated quartz cell for determination of antimony by atomic absorption spectrophotometry. Precision and accuracy data are presented. Results obtained on standard reference water samples agree with means established by interlaboratory studies. Spike recoveries for actual samples range from 90 to 114 percent. Replicate analyses of water samples of varying matrices give relative standard deviations from 3 to 10 percent.

  8. Impact process: an important geological phenomenon.

    PubMed

    Skala, R

    1996-01-01

    The impact process was for a long period of time, even after a wider acceptance among the geological community, considered to be a marginal phenomenon in the Earth sciences. The first decade or two have showed an importance of the process itself and consequent events only too clearly. The present paper is a review describing the history and development of the impact hypothesis, structure and origin of impact craters, influence of huge impacts on the living environment and other aspects of the impact process from the point of view of geology s.l.

  9. Preliminary geologic mapping of Arsia Mons, Mars

    NASA Technical Reports Server (NTRS)

    Zimbelman, James R.

    1991-01-01

    Geologic mapping of the Tharsis Montes at a scale of 1:500,000 was recently initiated as part of the Mars Geologic Mapping Program of NASA. Detailed mapping of the three large shield volcanoes and their surroundings will help to clarify the sequence of events which led to the formation of these features, as well as provide a basis for comparing the complex histories of the three related yet distinctive volcanic centers. Preliminary mapping of Arsia Mons at a scale of 1:2 M was carried out in preparation for detailed mapping. A map is presented along with a discussion of its contents.

  10. The Determining and Communicating the Role of Urban Fuels in Structure Loss During Large California Fire Events

    NASA Astrophysics Data System (ADS)

    Fotheringham, C. J.; Keeley, J. E.

    2010-12-01

    The relatively new focus of fire management in California on the Wildland-Urban Interface (WUI) has a greater potential to decrease losses of property relative to the previous focus on wildland landscapes. However, many of the modifications continue to occur on the wildland side of the interface in the form of fuel breaks and clearing/type-converting native vegetation around or near urban developments. There are guidelines for landscaping and irrigation in various zones around both individual structures and urban areas as a whole but a scientific basis for these guidelines is weak and[space]their effectiveness untested. In addition, although there are suggested lists of plants, standards for urban landscape are largely lacking. Planners, developers and the public in general sometimes lack sufficient information to make informed decisions about fire safety and no[no space]where is this more evident than with landscaping. Currently as part of the USGS MultiHazards Demonstration Project we are investigating the attributes of homes and associated landscaping associated with houses destroyed in recent wildfires. In this study we focused primarily[space]on the urban side of the interface to determine factors contributing to structure loss. This is[space]a post-hoc study of houses that were loss in large fires over the last decade throughout southern California. Houses were assessed with historical oblique aerial photos for adjacent vegetation characteristics, structural traits such as decks, patios and outbuildings, and location characteristics such as adjacent slope angle. Findings indicate that slope to the north and east, tree canopy overlap of structures, decks, and presence of ornamental acacia heavily impact whether a structure will survive. Information from this study will be communicated to community organizations such as fire safe councils to facilitate homeowner ability to improve fire safety in existing structures. In addition, guidelines for future

  11. Ultrasound- and microwave-assisted extractions followed by hydride generation inductively coupled plasma optical emission spectrometry for lead determination in geological samples.

    PubMed

    Welna, Maja; Borkowska-Burnecka, Jolanta; Popko, Malgorzata

    2015-11-01

    Followed the current idea of simplified sample pretratmet before analysis we evaluated the procedure for the determination of Pb in calcium-rich materials such as dolomites after ultrasound- or microwave- assisted extraction with diluted acids using hydride generation inductively coupled plasma optical emission spectrometry (HG-ICP-OES). Corresponding Pb hydride was generated in the reaction of an acidified sample solution with NaBH4 after pre-oxidation of Pb(II) to Pb(IV) by K3[Fe(CN)6]. Several chemical (acidic media: HCl, HNO3 or CH3COOH, concentration of the reductant as well as type and concentration of oxidazing agents) and physical (reagents flow rates, reaction coil length) parameters affecting the efficiency of plumbane formation were optimized in order to improve the detectability of Pb using HG-ICP-OES. Limitation of the method derived from the matrix effects was pointed out. Employing Pb separation by HG technique allows the significant reduction of interferences caused by sample matrix constituents (mainly Ca and Mg), nevertheless they could not be overcame at all, hence calibration based on the standard addition method was recommended for Pb quantification in dolomites. Under the selected conditions, i.e. 0.3 mol L(-1) HCl, HNO3 or CH3COOH, 1.5% NaBH4 and 3.0% K3[Fe(CN)6] the limits of detection (LODs) between 2.3-5.6 μg L(-1) (3.4-6.8 μg L(-1) considering matrix effects) and the precision below 5% were achieved. The accuracy of the procedure was verified by analysis of certified reference materials (NCS DC70308 (Carbonate Rock) and NIST 14000 (Bone Ash)) and recovery test with satisfactory results of Pb recoveries ranging between 94-108% (CRMs analysis) and 92-114% (standard addition method). The applicability of the proposed method was demonstrated by the determination of Pb in dolomites used by different fertiliser factories.

  12. Economic Geology (Oil & Gas)

    ERIC Educational Resources Information Center

    Geotimes, 1972

    1972-01-01

    Briefly reviews the worldwide developments in petroleum geology in 1971, including exploration, new fields, and oil production. This report is condensed from the October Bulletin of the American Association of Petroleum Geologists. (PR)

  13. 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)

  14. 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)

  15. 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.

  16. Geologic evolution of Arizona

    SciTech Connect

    Penny, J.P.; Reynolds, S.J.

    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 geologic evolution of the state as a whole rather than specific local areas. The papers are organized in terms of geologic eras: Proterozoic, Paleozoic, Mesozoic, and Cenozoic. The concluding section offers topical studies in the areas of geophysics, industrial minerals, uranium, oil and gas, geothermal resources, hydrogeology, and environmental geology. California readers will find much of interest in this research volume because many of the tectonic processes that formed Arizona also affected the development of this state.

  17. Economic Geology (Oil & Gas)

    ERIC Educational Resources Information Center

    Geotimes, 1972

    1972-01-01

    Briefly reviews the worldwide developments in petroleum geology in 1971, including exploration, new fields, and oil production. This report is condensed from the October Bulletin of the American Association of Petroleum Geologists. (PR)

  18. Scaling the Geologic Past

    ERIC Educational Resources Information Center

    Gerritts, Mary

    1975-01-01

    Describes construction of a Geologic Time Scale on a 100 foot roll of paper and suggests activities concerning its use. Includes information about fossils and suggestions for conducting a fossil field trip with students. (BR)

  19. The commensurability of environmental geology and petroleum geology

    SciTech Connect

    Argen, R.J.

    1990-05-01

    Environmental geology and petroleum geology are practical applications of pure geology. These two applied sciences differ with respect to their philosophical and ethical mandates. A good petroleum geologist finds hydrocarbons, but the role of a good environmental geologist is not well defined. If the good environmental geologist's role is not simply to protect the environment from the good petroleum geologist then how do the mandates of these geologists differ, yet remain compatible If the mandate of a good environmental geologist were to protect every natural resource from all managed use, then the good environmental geologist and the good petroleum geologist would forever be at war. This mandate provides no framework for agreement because it assumes the inherent worth of each natural resource is discoverable. If the mandate of a good environmental geologist is to discover how to maximize the long-term benefits of the managed use of natural resource, then both the good environmental geologist and the good petroleum geologist would agree that no natural resource has inherent worth. The value of a natural resource is not determined by what it is, but by how it enhances the quality of life for a particular class of sentient creatures. An instrumental theory of value will provide a medium for interim disagreement on how to enhance the quality of life for sentient creatures, and also will provide the means for a long-term agreement that the managed use of natural resources enhances the long-term quality of life for sentient creatures.

  20. Advances in Planetary Geology

    NASA Technical Reports Server (NTRS)

    Grant, John A., III; Nedell, Susan S.

    1987-01-01

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

  1. Geologic exploration of Mars

    NASA Technical Reports Server (NTRS)

    Plescia, J. B.

    1990-01-01

    The scientific objectives and methods involved in a geologic exploration of Mars from a manned outpost are discussed. The constraints on outpost activities imposed by the limited crew size, limited amount of time available for science, the limited diversity of scientific expertise, and the competition between scientific disciplines are addressed. Three examples of possible outpost locations are examined: the Olympus Mons aureole, Mangala Valles/Daedalia Planum, and Candor Chasma. The geologic work that could be done at each site is pointed out.

  2. United States Geological Survey Yearbook, fiscal year 1980

    USGS Publications Warehouse

    ,

    1981-01-01

    It is not very often that a single event is so overwhelming that it changes public perceptions of natural hazards for generations. Perhaps for the U.S. Geological Survey, the explosive volcanic activity of Mount St. Helens began such a change. After 101 years of careful science of the Earth's past and meticulous observations and assessments of the present, predictive earth science was in full public view. However vague and faint the glimpse of the future made possible by earth science, it was enough. Warnings were issued, thousands of lives were saved, and the age of real-time geology began. The Survey's basic mission has not changed, but the power of our analytical tools has increased by several orders of magnitude. The Survey's efforts to understand Earth processes and hydrologic principles continued with the collection, during fiscal year 1980, of valuable new data on the geologic origin and framework, seismicity, and mineral and energy resources of the United States. The Survey is also responsible for classification of the leasable minerals on Federal lands and the regulation of mineral exploration and development activities on Federal and Indian lands. As the principal earth science fact-gathering agency, the Survey provides information for sound decisionmaking by government and private industry. Industry uses the Survey's information in exploring for energy and minerals and improving their efforts to make development of energy and minerals compatible with environmental protection standards. Government uses the Survey's information in conducting leasing operations on public lands, in regulating the safe design and siting of nuclear plants, and in establishing guidelines for determining and locating areas that are subject to geologic hazards such as landslides, earthquakes, and volcanic eruptions. The Yearbook reports a broad range of the Survey's accomplishments during the past fiscal year and provides an overview of future directions. Many of the topics

  3. The geologic mapping of asteroid Vesta

    NASA Astrophysics Data System (ADS)

    Williams, D.; Yingst, A.; Garry, B.

    2014-07-01

    the resulting time-stratigraphic system and geologic timescale. Key results from the geologic mapping of Vesta include: 1) surface units are dominated by features and materials produced by two major impact events, the older Veneneia and younger Rheasilvia impacts at the south pole 2) both impacts produced a ridge-and-trough terrain as a tectonic response to the impacts, mapped as the Saturnalia Fossae and the Divalia Fossae Formations, respectively 3) stratigraphic analysis of Vesta's heavily cratered terrains show that portions of the original crust are preserved and predate the Veneneia impact 4) the Marcia impact event marks the beginning of Vesta's final stratigraphic period, including exposure of fresh bright and dark material and preservation of young bright-rayed and dark-rayed craters. We conclude that a geologic mapping campaign, including both global and regional mapping, can be conducted during the limited planetary nominal mission timeline, and is an excellent way to engage younger team members (graduate students and postdocs) in mission data analysis activities.

  4. Quaternary geology and geomorphology of the lower Deschutes River Canyon, Oregon.

    Treesearch

    Jim E. O' Connor; Janet H. Curran; Robin A. Beebee; Gordon E. Grant; Andrei. Sarna-Wojcicki

    2003-01-01

    The morphology of the Deschutes River canyon downstream of the Pelton-Round Butte dam complex is the product of the regional geologic history, the composition of the geologic units that compose the valley walls, and Quaternary processes and events. Geologic units within the valley walls and regional deformation patterns control overall valley morphology. Valley bottom...

  5. Students' Understanding of Large Numbers as a Key Factor in Their Understanding of Geologic Time

    ERIC Educational Resources Information Center

    Cheek, Kim A.

    2012-01-01

    An understanding of geologic time is comprised of 2 facets. Events in Earth's history can be placed in relative and absolute temporal succession on a vast timescale. Rates of geologic processes vary widely, and some occur over time periods well outside human experience. Several factors likely contribute to an understanding of geologic time, one of…

  6. Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory : determination of polycyclic aromatic hydrocarbon compounds in sediment by gas chromatography/mass spectrometry

    USGS Publications Warehouse

    Olson, Mary C.; Iverson, Jana L.; Furlong, Edward T.; Schroeder, Michael P.

    2004-01-01

    A method for the determination of 28 polycyclic aromatic hydrocarbons (PAHs) and 25 alkylated PAH homolog groups in sediment samples is described. The compounds are extracted from sediment by solvent extraction, followed by partial isolation using high-performance gel permeation chromatography. The compounds are identified and uantitated using capillary-column gas chromatography/mass spectrometry. The report presents performance data for full-scan ion monitoring. Method detection limits in laboratory reagent matrix samples range from 1.3 to 5.1 micrograms per kilogram for the 28 PAHs. The 25 groups of alkylated PAHs are homologs of five groups of isomeric parent PAHs. Because of the lack of authentic standards, these homologs are reported semiquantitatively using a response factor from a parent PAH or a specific alkylated PAH. Precision data for the alkylated PAH homologs are presented using two different standard reference manuals produced by the National Institute of Standards and Technology: SRM 1941b and SRM 1944. The percent relative standard deviations for identified alkylated PAH homolog groups ranged from 1.55 to 6.98 for SRM 1941b and from 6.11 to 12.0 for SRM 1944. Homolog group concentrations reported under this method include the concentrations of individually identified compounds that are members of the group. Organochlorine (OC) pesticides--including toxaphene, polychlorinated biphenyls (PCBs), and organophosphate (OP) pesticides--can be isolated simultaneously using this method. In brief, sediment samples are centrifuged to remove excess water and extracted overnight with dichloromethan (95 percent) and methanol (5 percent). The extract is concentrated and then filtered through a 0.2-micrometer polytetrafluoroethylene syringe filter. The PAH fraction is isolated by quantitatively injecting an aliquot of sample onto two polystyrene-divinylbenzene gel-permeation chromatographic columns connected in series. The compounds are eluted with dichloromethane

  7. Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory; determination of dissolved arsenic, boron, lithium, selenium, strontium, thallium, and vanadium using inductively coupled plasma-mass spectrometry

    USGS Publications Warehouse

    Garbarino, John R.

    1999-01-01

    The inductively coupled plasma?mass spectrometric (ICP?MS) methods have been expanded to include the determination of dissolved arsenic, boron, lithium, selenium, strontium, thallium, and vanadium in filtered, acidified natural water. Method detection limits for these elements are now 10 to 200 times lower than by former U.S. Geological Survey (USGS) methods, thus providing lower variability at ambient concentrations. The bias and variability of the method was determined by using results from spike recoveries, standard reference materials, and validation samples. Spike recoveries at 5 to 10 times the method detection limit and 75 micrograms per liter in reagent-water, surface-water, and groundwater matrices averaged 93 percent for seven replicates, although selected elemental recoveries in a ground-water matrix with an extremely high iron sulfate concentration were negatively biased by 30 percent. Results for standard reference materials were within 1 standard deviation of the most probable value. Statistical analysis of the results from about 60 filtered, acidified natural-water samples indicated that there was no significant difference between ICP?MS and former USGS official methods of analysis.

  8. Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory; determination of whole-water recoverable arsenic, boron, and vanadium using inductively coupled plasma-mass spectrometry

    USGS Publications Warehouse

    Garbarino, John R.

    2000-01-01

    Analysis of in-bottle digestate by using the inductively coupled plasma?mass spectrometric (ICP?MS) method has been expanded to include arsenic, boron, and vanadium. Whole-water samples are digested by using either the hydrochloric acid in-bottle digestion procedure or the nitric acid in-bottle digestion procedure. When the hydrochloric acid in-bottle digestion procedure is used, chloride must be removed from the digestate by subboiling evaporation before arsenic and vanadium can be accurately determined. Method detection limits for these elements are now 10 to 100 times lower than U.S. Geological Survey (USGS) methods using hydride generation? atomic absorption spectrophotometry (HG? AAS) and inductively coupled plasma? atomic emission spectrometry (ICP?AES), thus providing lower variability at ambient concentrations. The bias and variability of the methods were determined by using results from spike recoveries, standard reference materials, and validation samples. Spike recoveries in reagent-water, surface-water, ground-water, and whole-water recoverable matrices averaged 90 percent for seven replicates; spike recoveries were biased from 25 to 35 percent low for the ground-water matrix because of the abnormally high iron concentration. Results for reference material were within one standard deviation of the most probable value. There was no significant difference between the results from ICP?MS and HG?AAS or ICP?AES methods for the natural whole-water samples that were analyzed.

  9. DIGITAL GEOLOGIC MAP OF SHERMAN QUADRANGLE, NORTH CENTRAL TEXAS (CD-ROM)

    EPA Science Inventory

    This compact disc contains digital data sets of the surficial geology and geologic faults for the 1:250,000-scale Sherman quadrangle, North Central Texas, and can be used to make geologic maps, and determine approximate areas and locations of various geologic units. The source d...

  10. DIGITAL GEOLOGIC MAP OF SHERMAN QUADRANGLE, NORTH CENTRAL TEXAS (CD-ROM)

    EPA Science Inventory

    This compact disc contains digital data sets of the surficial geology and geologic faults for the 1:250,000-scale Sherman quadrangle, North Central Texas, and can be used to make geologic maps, and determine approximate areas and locations of various geologic units. The source d...

  11. Surficial Geology of Mount Rainier National Park, Washington

    USGS Publications Warehouse

    Crandell, Dwight Raymond

    1969-01-01

    Much of the ground surface around Mount Rainier volcano is directly underlain by loose geologic deposits that veneer the hard rock formations. Examples of these deposits are sand and gravel bars along the rivers, ridges of loose rock debris beside the glaciers, and sloping aprons of rock fragments beneath almost every cliff. Even though they are generally thin and inconspicuous when compared with the rock formations, these surficial deposits are clues to geologic events that have profoundly influenced the shape of the park's landscape. Thus, from the character and extent of glacial deposits one can judge the age and size of former glaciers that carved the cirques and deep canyons of the park; from the mudflows which streamed down nearly every valley one can infer the age and size of huge landslides of the past that helped determine Mount Rainier's present shape; and from the pumice deposits some of the volcano's recent eruptive activity can be reconstructed. The map (plate 1, in pocket) that accompanies this description of the surficial deposits of Mount Rainier National Park shows the location of the various geologic formations, and the explanation shows the formations arranged in order of their relative age, with the oldest at the bottom. The text describes the surficial deposits in sequence from older to younger. A discussion of the pumice deposits of the park, which were not mapped, is followed by a description of the formations shown on the geologic map. Inspection of the geologic map may lead the viewer to question why the surficial deposits are shown in more detail in a zone several miles wide around the base of the volcano than elsewhere. This is partly because the zone is largely near or above timberline, relatively accessible, and the surficial deposits there can be readily recognized, differentiated, and mapped. In contrast, access is more difficult in the heavily timbered parts of the park, and surficial deposits there are generally blanketed by a dense

  12. Cassini's geological and compositional view of Tethys

    NASA Astrophysics Data System (ADS)

    Stephan, Katrin; Wagner, Roland; Jaumann, Ralf; Clark, Roger N.; Cruikshank, Dale P.; Brown, Robert H.; Giese, Bernd; Roatsch, Thomas; Filacchione, Gianrico; Matson, Dennis; Ore, Cristina Dalle; Capaccioni, Fabrizio; Baines, Kevin H.; Rodriguez, Sebastien; Krupp, Norbert; Buratti, Bonnie J.; Nicholson, Phil D.

    2016-08-01

    The Saturnian satellite Tethys exhibits geological and spectral properties, whose appearance, nature and spatial distribution partly mirror those identified on the neighboring satellites Dione and Rhea or fit to the picture how spectral surface properties are expected to change from one satellite to the other within the inner Saturnian system. However, we also identified spectral variations that are unique in the Saturnian system. Whereas geologically young surface features are characterized by pure H2O-ice composition with relatively large particles, which match the particle sizes measured for fresh surface features also on Dione and Rhea, geologically old weathered regions are dominated by submicron-sized ice particles. Our investigations confirm that the Odysseus impact event did not cause the formation of Tethys' extended graben system Ithaca Chasma. On the contrary, Odysseus might be responsible for the N-S trending 'icy' bands that mark Tethys' surface in the center of its leading and trailing hemisphere.

  13. 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.

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

    NASA Technical Reports Server (NTRS)

    Eppler, Dean B.

    2010-01-01

    The science of field geology is the investigative process of determining the distribution of rock units and structures on a planet s surface, and it is the first order data set that informs all subsequent studies of a planet, such as geochemistry, geochronology, geophysics or remote sensing. These allied sciences, as important as they are, derive the basis of their understanding from the knowledge of the geology of a given location. When we go back to the Moon, and on to Mars, the surface systems we deploy will need to support the conduct of field geology if these endeavors are to be scientifically useful. This lecture will consider what field geology is about - why it s important, how we do it, how the conduct of field geology informs many other sciences, and how it will affect the design of surface systems and implementation of operations in the future.

  15. Analysis of geologic terrain models for determination of optimum SAR sensor configuration and optimum information extraction for exploration of global non-renewable resources. Pilot study: Arkansas Remote Sensing Laboratory, part 1, part 2, and part 3

    NASA Technical Reports Server (NTRS)

    Kaupp, V. H.; Macdonald, H. C.; Waite, W. P.; Stiles, J. A.; Frost, F. S.; Shanmugam, K. S.; Smith, S. A.; Narayanan, V.; Holtzman, J. C. (Principal Investigator)

    1982-01-01

    Computer-generated radar simulations and mathematical geologic terrain models were used to establish the optimum radar sensor operating parameters for geologic research. An initial set of mathematical geologic terrain models was created for three basic landforms and families of simulated radar images were prepared from these models for numerous interacting sensor, platform, and terrain variables. The tradeoffs between the various sensor parameters and the quantity and quality of the extractable geologic data were investigated as well as the development of automated techniques of digital SAR image analysis. Initial work on a texture analysis of SEASAT SAR imagery is reported. Computer-generated radar simulations are shown for combinations of two geologic models and three SAR angles of incidence.

  16. Geology, S-Pb isotopes, and 40Ar/39Ar geochronology of the Zhaxikang Sb-Pb-Zn-Ag deposit in Southern Tibet: implications for multiple mineralization events at Zhaxikang

    NASA Astrophysics Data System (ADS)

    Sun, Xiang; Zheng, Youye; Pirajno, Franco; McCuaig, T. Campbell; Yu, Miao; Xia, Shenlan; Song, Qingjie; Chang, Huifang

    2017-07-01

    Several Au, Sb, Sb-Au, Pb-Zn, and Sb-Pb-Zn-Ag deposits are present throughout the North Himalaya in southern Tibet, China. The largest Sb-Pb-Zn-Ag deposit is Zhaxikang (18 Mt at 0.6 wt% Sb, 2.0 wt% Pb, 3.5 wt% Zn, and 78 g/t Ag). Zhaxikang veins are hosted within N-S trending faults, which crosscut the Early-Middle Jurassic Ridang Formation consisting of shale interbedded with sandstone and limestone deposited on a passive continental margin. Ore paragenesis indicates that Zhaxikang mineralization occurred in two main phases composed of six total stages. The initial phase was characterized by assemblages of fine-grained Mn-Fe carbonate + arsenopyrite + pyrite + sphalerite (stage 1), followed by relatively coarse-grained Mn-Fe carbonate + Fe-rich sphalerite + galena + pyrite (stage 2). The second phase was marked by assemblages of quartz + pyrite + Fe-poor sphalerite and Ag-rich galena + tetrahedrite + sericite (stage 3), quartz + Sb-Pb sulfosalt minerals mainly composed of boulangerite and jamesonite (stage 4), quartz + stibnite ± cinnabar (stage 5), and quartz ± calcite (stage 6). Sulfides of stage 2 have δ34SV-CDT of 8.4-12.0‰, 206Pb/204Pb ratios of 19.648 to 19.659, 207Pb/204Pb ratios of 15.788 to 15.812, and 208Pb/204Pb ratios of 40.035 to 40.153. Sulfides of stage 3 have similar δ34SV-CDT of 6.1-11.2‰ and relatively more radiogenic lead isotopes (206Pb/204Pb = 19.683-19.792). Stage 4 Sb-Pb sulfosalt minerals have δ34SV-CDT of 5.0-7.2‰ and even more radiogenic lead (206Pb/204Pb = 19.811-19.981). By contrast, stibnite of stage 5 has δ34SV-CDT of 4.5-7.8‰ and less radiogenic lead (206Pb/204Pb = 18.880-18.974). Taken together with the geological observations that the Pb-Zn-bearing Mn-Fe carbonate veins were crosscut by various types of quartz veins, sphalerite and galena of stage 2 underwent dissolution and remobilization, and that Sb-Pb(-Fe) sulfosalts formed at the expense of Pb from stage 2 galena and of Fe from stage 2 sphalerite, we argue that

  17. Methods of Analysis by the U.S. Geological Survey National Water Quality Laboratory - Determination of Moderate-Use Pesticides and Selected Degradates in Water by C-18 Solid-Phase Extraction and Gas Chromatography/Mass Spectrometry

    USGS Publications Warehouse

    Sandstrom, Mark W.; Stroppel, Max E.; Foreman, William T.; Schroeder, Michael P.

    2001-01-01

    A method for the isolation and analysis of 21 parent pesticides and 20 pesticide degradates in natural-water samples is described. Water samples are filtered to remove suspended particulate matter and then are pumped through disposable solid-phase-extraction columns that contain octadecyl-bonded porous silica to extract the analytes. The columns are dried by using nitrogen gas, and adsorbed analytes are eluted with ethyl acetate. Extracted analytes are determined by capillary-column gas chromatography/mass spectrometry with selected-ion monitoring of three characteristic ions. The upper concentration limit is 2 micrograms per liter (?g/L) for most analytes. Single-operator method detection limits in reagent-water samples range from 0.00 1 to 0.057 ?g/L. Validation data also are presented for 14 parent pesticides and 20 degradates that were determined to have greater bias or variability, or shorter holding times than the other compounds. The estimated maximum holding time for analytes in pesticide-grade water before extraction was 4 days. The estimated maximum holding time for analytes after extraction on the dry solid-phase-extraction columns was 7 days. An optional on-site extraction procedure allows for samples to be collected and processed at remote sites where it is difficult to ship samples to the laboratory within the recommended pre-extraction holding time. The method complements existing U.S. Geological Survey Method O-1126-95 (NWQL Schedules 2001 and 2010) by using identical sample preparation and comparable instrument analytical conditions so that sample extracts can be analyzed by either method to expand the range of analytes determined from one water sample.

  18. Impact, and its implications for geology

    NASA Technical Reports Server (NTRS)

    Marvin, Ursula B.

    1988-01-01

    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.

  19. Geologic map of Mars

    USGS Publications Warehouse

    Tanaka, Kenneth L.; Skinner, James A.; Dohm, James M.; Irwin, Rossman P.; Kolb, Eric J.; Fortezzo, Corey M.; Platz, Thomas; Michael, Gregory G.; Hare, Trent M.

    2014-01-01

    This global geologic map of Mars, which records the distribution of geologic units and landforms on the planet's surface through time, is based on unprecedented variety, quality, and quantity of remotely sensed data acquired since the Viking Orbiters. These data have provided morphologic, topographic, spectral, thermophysical, radar sounding, and other observations for integration, analysis, and interpretation in support of geologic mapping. In particular, the precise topographic mapping now available has enabled consistent morphologic portrayal of the surface for global mapping (whereas previously used visual-range image bases were less effective, because they combined morphologic and albedo information and, locally, atmospheric haze). Also, thermal infrared image bases used for this map tended to be less affected by atmospheric haze and thus are reliable for analysis of surface morphology and texture at even higher resolution than the topographic products.

  20. Geology at Yucca Mountain

    SciTech Connect

    1993-05-01

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

  1. The geology of Ganymede

    NASA Astrophysics Data System (ADS)

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

    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.

  2. 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.

  3. 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.

  4. 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.

  5. Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory; determination of pesticides in water by Carbopak-B solid-phase extraction and high-preformance liquid chromatography

    USGS Publications Warehouse

    Werner, Stephen L.; Burkhardt, Mark R.; DeRusseau, Sabrina N.

    1996-01-01

    In accordance with the needs of the National Water-Quality Assessment Program (NAWQA), the U.S. Geological Survey has developed and implemented a graphitized carbon-based solid-phase extraction and high-performance liquid chromatographic analytical method. The method is used to determine 41 pesticides and pesticide metabolites that are not readily amenable to gas chromatography or other high-temperature analytical techniques. Pesticides are extracted from filtered environmental water samples using a 0.5-gram graphitized carbon-based solid-phase cartridge, eluted from the cartridge into two analytical fractions, and analyzed using high-performance liquid chromatography with photodiode-array detection. The upper concentration limit is 1.6 micrograms per liter (=B5g/L) for most compounds. Single-operator method detection limits in organic-free water samples ranged from 0.006 to 0.032 =B5g/L= Recoveries in organic-free water samples ranged from 37 to 88 percent. Recoveries in ground- and surface-water samples ranged from 29 to 94 percent. An optional on-site extraction procedure allows for samples to be collected and processed at remote sites where it is difficult to ship samples to the laboratory within the recommended pre-extraction holding time of 7 days.

  6. Chemical forms of sulfur in geological and archeological asphaltenes from Middle East, France, and Spain determined by sulfur K- and L-edge X-ray absorption near-edge structure spectroscopy

    NASA Astrophysics Data System (ADS)

    Sarret, Géraldine; Connan, Jacques; Kasrai, Masoud; Bancroft, G. Michael; Charrié-Duhaut, Armelle; Lemoine, Sylvie; Adam, Pierre; Albrecht, Pierre; Eybert-Bérard, Laurent

    1999-11-01

    Asphaltene samples extracted from archeological and geological bitumens from the Middle East, France, and Spain were studied by sulfur K- and L-edge X-ray absorption near-edge structure (XANES) spectroscopy in combination with isotopic analyses (δ 13C and δD). Within each series, the samples were genetically related by their δ 13C values. The gross and elemental composition and the δD values were used to characterize the weathering state of the samples. Sulfur K- and L-edge XANES results show that in all the samples, dibenzothiophenes are the dominant forms of sulfur. In the least oxidized asphaltenes, minor species include disulfides, alkyl and aryl sulfides, and sulfoxides. With increasing alteration the proportion of oxidized sulfur (sulfoxides, sulfones, sulfonates and sulfates) increases, whereas the disulfide and sulfide content decreases. This evolution is observed in all the series, regardless of the origin of the asphaltenes. This work illustrates the advantages of XANES spectroscopy as a selective probe for determining sulfur speciation in natural samples. It also shows that S K- and L-edge XANES spectroscopy are complementary for identifying the oxidized and reduced forms of sulfur, respectively.

  7. Method of analysis and quality-assurance practices by the U.S. Geological Survey Organic Geochemistry Research Group; determination of geosmin and methylisoborneol in water using solid-phase microextraction and gas chromatography/mass spectrometry

    USGS Publications Warehouse

    Zimmerman, L.R.; Ziegler, A.C.; Thurman, E.M.

    2002-01-01

    A method for the determination of two common odor-causing compounds in water, geosmin and 2-methylisoborneol, was modified and verified by the U.S. Geological Survey's Organic Geochemistry Research Group in Lawrence, Kansas. The optimized method involves the extraction of odor-causing compounds from filtered water samples using a divinylbenzene-carboxen-polydimethylsiloxane cross-link coated solid-phase microextraction (SPME) fiber. Detection of the compounds is accomplished using capillary-column gas chromatography/mass spectrometry (GC/MS). Precision and accuracy were demonstrated using reagent-water, surface-water, and ground-water samples. The mean accuracies as percentages of the true compound concentrations from water samples spiked at 10 and 35 nanograms per liter ranged from 60 to 123 percent for geosmin and from 90 to 96 percent for 2-methylisoborneol. Method detection limits were 1.9 nanograms per liter for geosmin and 2.0 nanograms per liter for 2-methylisoborneol in 45-milliliter samples. Typically, concentrations of 30 and 10 nanograms per liter of geosmin and 2-methylisoborneol, respectively, can be detected by the general public. The calibration range for the method is equivalent to concentrations from 5 to 100 nanograms per liter without dilution. The method is valuable for acquiring information about the production and fate of these odor-causing compounds in water.

  8. Geologic controls on the West Antarctic Ice Sheet

    NASA Technical Reports Server (NTRS)

    Anandakrishnan, Sridhar

    1993-01-01

    The stability of the West Antarctic Ice Sheet is intertwined with its geologic history. The sub-ice geology and the possibility of active rifting and associated elevated heat-flux and volcanism might be determining factors in ice-sheet behavior. Seismic monitoring of natural events at the base of Ice Stream C reveals the presence of a young sedimentary basin beneath the ice stream. The sediments are presumed to be of glacio-marine origin, similar to those beneath Ice Stream B and in the Ross Sea. The young sediments are approximately 1/2 km thick at UpC camp, but thin abruptly southward to 100 m or less. We hypothesize the presence of a fault with a throw of 400 m to account for this (though we have not directly detected the fault), rather than invoking unrealistic basement dips. To extend these studies to critical inland regions, we suggest an expanded explosive-source seismic survey of the Byrd Subglacial Basin to determine the extent and character of the hypothesized rift basin. High-resolution seismic monitoring will detect layering in the sedimentary column, as well as possibly imaging faults directly.

  9. Titan's global geologic processes

    NASA Astrophysics Data System (ADS)

    Malaska, Michael; Lopes, Rosaly M. C.; Schoenfeld, Ashley; Birch, Samuel; Hayes, Alexander; Williams, David A.; Solomonidou, Anezina; Janssen, Michael A.; Le Gall, Alice; Soderblom, Jason M.; Neish, Catherine; Turtle, Elizabeth P.; Cassini RADAR Team

    2016-10-01

    We have mapped the Cassini SAR imaged areas of Saturn's moon Titan in order to determine the geological properties that modify the surface [1]. We used the SAR dataset for mapping, but incorporated data from radiometry, VIMS, ISS, and SARTopo for terrain unit determination. This work extends our analyses of the mid-latitude/equatorial Afekan Crater region [2] and in the southern and northern polar regions [3]. We placed Titan terrains into six broad terrain classes: craters, mountain/hummocky, labyrinth, plains, dunes, and lakes. We also extended the fluvial mapping done by Burr et al. [4], and defined areas as potential cryovolcanic features [5]. We found that hummocky/mountainous and labyrinth areas are the oldest units on Titan, and that lakes and dunes are among the youngest. Plains units are the largest unit in terms of surface area, followed by the dunes unit. Radiometry data suggest that most of Titan's surface is covered in high-emissivity materials, consistent with organic materials, with only minor exposures of low-emissivity materials that are consistent with water ice, primarily in the mountain and hummocky areas and crater rims and ejecta [6, 7]. From examination of terrain orientation, we find that landscape evolution in the mid-latitude and equatorial regions is driven by aeolian processes, while polar landscapes are shaped by fluvial, lacrustine, and possibly dissolution or volatilization processes involving cycling organic materials [3, 8]. Although important in deciphering Titan's terrain evolution, impact processes play a very minor role in the modification of Titan's landscape [9]. We find no evidence for large-scale aqueous cryovolcanic deposits.References: [1] Lopes, R.M.C. et al. (2010) Icarus, 205, 540-558. [2] Malaska, M.J. et al. (2016) Icarus, 270, 130-161. [3] Birch et al., in revision. [4] Burr et al. (2013) GSA Bulletin 125, 299-321. [5] Lopes et al. JGR: Planets, 118, 1-20. [6] Janssen et al., (2009) Icarus, 200, 222-239. [7] Janssen

  10. Geological Corrections in Gravimetry

    NASA Astrophysics Data System (ADS)

    Mikuška, J.; Marušiak, I.

    2015-12-01

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

  11. A Regional Guide to Iowa Landforms. Iowa Geological Survey Educational Series 3.

    ERIC Educational Resources Information Center

    Prior, Jean Cutler

    Presented is a non-technical account of the geological appearance and history of the state of Iowa. Included are Iowa's landscape features, geologic events, and processes that shaped the landscape. Maps and numerous illustrations picture the events and landforms described. Each of the state's seven principal landform regions is discussed in…

  12. Planetary geological processes

    NASA Astrophysics Data System (ADS)

    Lopes, Rosaly M. C.; Solomonidou, Anezina

    2014-11-01

    In this introduction to planetary geology, we review the major geologic processes affecting the solid bodies of the solar system, namely volcanism, tectonism, impact cratering, and erosion. We illustrate the interplay of these processes in different worlds, briefly reviewing how they affect the surfaces of the Earth's Moon, Mercury, Venus and Mars, then focusing on two very different worlds: Jupiter's moon Io, the most volcanically active object in the solar system, and Saturn's moon Titan, where the interaction between a dense atmosphere and the surface make for remarkably earth-like landscapes despite the great differences in surface temperature and composition.

  13. Tectonic Events May Have Triggered the Cambrian Explosion

    NASA Astrophysics Data System (ADS)

    Wendel, JoAnna

    2014-11-01

    Major geological changes causing sea level rise at the start of the Cambrian period (540-490 million years ago) could have kick-started the Cambrian Explosion—a geological time period when most major phyla of life suddenly appeared in the fossil record. A paper published in the November issue of Geology (doi:10.1130/G35886.1) proposes a new geological mechanism for this event.

  14. Spatial Visualization in Introductory Geology Courses

    NASA Astrophysics Data System (ADS)

    Reynolds, S. J.

    2004-12-01

    Visualization is critical to solving most geologic problems, which involve events and processes across a broad range of space and time. Accordingly, spatial visualization is an essential part of undergraduate geology courses. In such courses, students learn to visualize three-dimensional topography from two-dimensional contour maps, to observe landscapes and extract clues about how that landscape formed, and to imagine the three-dimensional geometries of geologic structures and how these are expressed on the Earth's surface or on geologic maps. From such data, students reconstruct the geologic history of areas, trying to visualize the sequence of ancient events that formed a landscape. To understand the role of visualization in student learning, we developed numerous interactive QuickTime Virtual Reality animations to teach students the most important visualization skills and approaches. For topography, students can spin and tilt contour-draped, shaded-relief terrains, flood virtual landscapes with water, and slice into terrains to understand profiles. To explore 3D geometries of geologic structures, they interact with virtual blocks that can be spun, sliced into, faulted, and made partially transparent to reveal internal structures. They can tilt planes to see how they interact with topography, and spin and tilt geologic maps draped over digital topography. The GeoWall system allows students to see some of these materials in true stereo. We used various assessments to research the effectiveness of these materials and to document visualization strategies students use. Our research indicates that, compared to control groups, students using such materials improve more in their geologic visualization abilities and in their general visualization abilities as measured by a standard spatial visualization test. Also, females achieve greater gains, improving their general visualization abilities to the same level as males. Misconceptions that students carry obstruct

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

    USGS Publications Warehouse

    ,

    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.

  16. Geologic controls on radon

    SciTech Connect

    Gates, A.E.; Gundersen, L.C.S.

    1992-01-01

    This text provides a review of recent research on geological controls of [sup 222]Rn concentrations in soil gas in relation to the problem of high indoor radon concentrations in houses. The importance of the subject matter is highlighted in the preface by the observation that the US Environmental Protection Agency (EPA) estimates that 15,000 to 25,000 deaths result from radon-induced lung cancer each year in the United States. The text contains 8 Chapters: (1) Geology of radon in the United States; (2) Sensitivity of soil radon to geology and the distribution of radon and uranium in the Hylas Zone Area, Virginia; (3) Geologic and environmental implications of high soil-gas radon concentrations in The Great Valley, Jefferson and Berkeley Counties, West Virginia; (4) Soil radon distribution in glaciated areas: an example from the New Jersey Highlands; (5) Radon in the coastal plain of Texas, Alabama, and New Jersey; (6) Effects of weather and soil characteristics on temporal variations in soil-gas radon concentrations; (7) A theoretical model for the flux of radon from rock to ground water; (8) The influence of season, bedrock, overburden, and house construction on airborne levels of radon in Maine homes. The individual chapters are written by different authors in the form of self-contained research papers, each of which is followed by a comprehensive list of references.

  17. 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."…

  18. Geology: The Active Earth.

    ERIC Educational Resources Information Center

    Braus, Judy, Ed.

    1987-01-01

    Ranger Rick's NatureScope is a creative education series dedicated to inspiring in children an understanding and appreciation of the natural world while developing the skills they will need to make responsible decisions about the environment. The topic of this issue is "Geology: The Active Earth." Contents are organized into the…

  19. 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.

  20. Briefing on geological sequestration

    EPA Science Inventory

    Geological sequestration (GS) is generally recognized as the injection and long-term (e.g., hundreds to thousands of years) trapping of gaseous, liquid or supercritical carbon dioxide (CO2) in subsurface media – primarily saline formations, depleted or nearly depleted oil and gas...