Science.gov

Sample records for earth movements geophysics

  1. GEOPHYSICS: Atmosphere Drives Earth's Tipsiness.

    PubMed

    Kerr, R A

    2000-08-04

    For more than a century, geophysicists who track Earth's rotation have sensed a rhythmic unsteadiness about the planet, an ever-so-slight wobbling whose source remained frustratingly mysterious. But researchers have been homing in on the roots of the so-called Chandler wobble, and now a report in the 1 August issue of Geophysical Research Letters fingers the shifting pressures of the deep sea and ultimately the fickle winds of the atmosphere.

  2. Earth Rotational Variations Excited by Geophysical Fluids

    NASA Technical Reports Server (NTRS)

    Chao, Benjamin F.

    2004-01-01

    Modern space geodetic measurement of Earth rotation variations, particularly by means of the VLBI technique, has over the years allowed studies of Earth rotation dynamics to advance in ever-increasing precision, accuracy, and temporal resolution. A review will be presented on our understanding of the geophysical and climatic causes, or "excitations". for length-of-day change, polar motion, and nutations. These excitations sources come from mass transports that constantly take place in the Earth system comprised of the atmosphere, hydrosphere, cryosphere, lithosphere, mantle, and the cores. In this sense, together with other space geodetic measurements of time-variable gravity and geocenter motion, Earth rotation variations become a remote-sensing tool for the integral of all mass transports, providing valuable information about the latter on a wide range of spatial and temporal scales. Future prospects with respect to geophysical studies with even higher accuracy and resolution will be discussed.

  3. Geophysical Effects of the Earth's Monthly Motion

    NASA Astrophysics Data System (ADS)

    Sidorenkov, N. S.; Zhigailo, T. S.

    The generation of a lunar tidal force is a major geophysical effect of the Earth's monthly motion.It is shown that synoptic processes vary simultaneously with tidal oscillations of the Earth's rotation rate and weather exhibits changes near their extremes, i.e., when the Earth is in certain positions on its monthly orbit.It is found that the quasi-biennial oscillation of the wind direction in the equatorial stratosphere is a combined oscillation caused by three periodic processes experienced by the atmosphere: (a) lunisolar tides, (b) the precession of the orbit of the Earth's monthly rotation around the barycenter of the Earth-Moon system, and (c) the motion of the perigee of this orbit.Interference of the 1.20-year Chandler wobble with sidereal, anomalistic, and synodic lunar oscillations gives rise to beats, i.e., to slow periodic variations in the wobble amplitude with periods of 32 to 51 years.

  4. Solid-Earth Geophysics in Latinamerica

    NASA Astrophysics Data System (ADS)

    Urrutia-F, J.

    2003-12-01

    Geophysical research increasingly requires of multidisciplinary global approaches. This is particularly the case on Earth system science, where studies of our planet attempt to integrate phenomena from the inner core to surface, hydrosphere, atmosphere, and beyond the magnetosphere into our solar system. To accomplish this, studies span wide ranges of spatial and temporal scales. Increasing understanding of how deeply interrelated are the Earth components and processes, the potential global impact of human activities, and view of our planet as a spaceship journeying in the solar system and galaxy emphasize the need of international cooperation. New tools are being developed to investigate the planet at different scales, with high spatial-temporal resolution, and we say - Earth scientists (particularly from highly-developed countries) do conduct global research. In this context, what is the situation in developing countries? Do all studies in foreign countries classify as international research? - Foreign countries to some of us are the home and study areas for other researchers. What are the conditions, facilities, projects and views of those other researchers? We attempt to examine some of these questions from an inside analysis and some examples in solid Earth geophysics from a Latinamerican country. How is the situation, size of research community, education and training, facilities, economic support, major problems, participation in international programs, and bilateral and multinational collaboration? What are the perspectives for future development within the region and in an international context? International research collaboration has an immense potential and is clearly needed for study of our planet. Understanding it in terms of unselfish cooperation in equal terms with fellow researchers is yet a major challenge to make the most of that potential.

  5. Geophysical Monitoring of Geodynamic Processes of Central Armenia Earth Crust

    NASA Astrophysics Data System (ADS)

    Avetyan, R.; Pashayan, R.

    2016-12-01

    The method of geophysical monitoring of earth crust was introduced. It allows by continuous supervision to track modern geodynamic processes of Armenia. Methodological practices of monitoring come down to allocation of a signal which reflects deformation of rocks. The indicators of deformations are not only deviations of geophysical indicators from certain background values, but also parameters of variations of these indicators. Data on changes of parameters of barometric efficiency and saw tooth oscillations of underground water level before seismic events were received. Low-amplitude periodic fluctuations of water level are the reflection of geodynamic processes taking place in upper levels of earth crust. There were recorded fluctuations of underground water level resulting from luni-solar tides and enabling to control the systems of borehole-bed in changes of voluminous deformations. The slow lowering (raising) of underground water level in the form of trend reflects long-period changes of stress-deformative state of environment. Application of method promotes identification of medium-term precursors on anomalous events of variations of geomagnetic field, change of content of subsoil radon, dynamics of level of underground water, geochemistry and water temperature. Increase of activity of geodynamic processes in Central Armenian tectonic complex is observed to change macro component Na+, Ca2+, Mg2-, CL-, SO42-, HCO3-, H4SiO4, pH and gas - CO2 structure of mineral water. Modern geodynamic movements of earth crust of Armenia are the result of seismic processes and active geodynamics of deep faults of longitudinal and transversal stretching. Key Words: monitoring, hydrogeodynamics, geomagnetic field, seismicity, deformation, earth crust

  6. Evidence for a critical Earth: the New Geophysics

    NASA Astrophysics Data System (ADS)

    Crampin, Stuart; Gao, Yuan

    2015-04-01

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

  7. Geophysics of an Oceanic Ice Shell on Snowball Earth

    NASA Technical Reports Server (NTRS)

    Gaidos, E. J.

    2000-01-01

    Kirschvink proposed Precambrian low-latitude glaciation could result in an albedo-driven catastrophic runaway to a "Snowball Earth" state in which pack ice up to 1 km thick covered the world ocean. The geophysical state of an ice crust on a Snowball Earth is examined.

  8. Geophysics of an Oceanic Ice Shell on Snowball Earth

    NASA Technical Reports Server (NTRS)

    Gaidos, E. J.

    2000-01-01

    Kirschvink proposed Precambrian low-latitude glaciation could result in an albedo-driven catastrophic runaway to a "Snowball Earth" state in which pack ice up to 1 km thick covered the world ocean. The geophysical state of an ice crust on a Snowball Earth is examined.

  9. Progress in geophysical aspects of the rotation of the earth

    NASA Technical Reports Server (NTRS)

    Lambeck, K.

    1978-01-01

    The geophysical causes and consequences of the Earth's rotation are reviewed. Specific topics covered include: (1) the motion of the rotation axis in space, precession and nutation; (2) the motion of the rotation axis relative to the Earth, polar motion; and (3) the rate of rotation about this axis, or changes in the length of day. Secular decrease in obliquity and evolution of the Earth-Moon system are also discussed.

  10. PREFACE: Padjadjaran Earth Dialogues: International Symposium on Geophysical Issues, PEDISGI

    NASA Astrophysics Data System (ADS)

    Rosandi, Y.; Urbassek, H. M.; Yamanaka, H.

    2016-01-01

    This issue of IOP Conference Series: Earth and Environmental Science contains selected papers presented at the Padjadjaran Earth Dialogues: International Symposium on Geophysical Issues, PEDISGI. The meeting was held from June 8 to 10, 2015, at the Bale-Sawala of Universitas Padjadjaran in Jatinangor, Indonesia. The PEDISGI is a symposium to accommodate communication between researchers, in particular geophysicists and related scientists, and to enable sharing of knowledge and research findings concerning local and global geophysical issues. The symposium was attended by 126 participants and 64 contributors from Indonesian universities and the neighbouring countries in four categories, viz. Theoretical and Computational Geophysics, Environmental Geophysics, Geophysical Explorations, and Geophysical Instrumentations and Methods. The symposium was accompanied by a dialog, discussing a chosen topic regarding environmental and geological problems of relevance for the Indonesian archipelago and the surrounding regions. For this first event the topic was ''The formation of Bandung-Basin between myths and facts: Exemplary cultural, geological and geophysical study on the evolution of the earth surface'', presented by invited speakers and local experts. This activity was aimed at extending our knowledge on this particular subject, which may have global impact. This topic was augmented by theoretical background lectures on the earth's surface formation, presented by the invited speakers of the symposium. The meeting would not have been successful without the assistance of the local organizing committee. We want to specially thank Irwan A. Dharmawan for managing the programme, Anggie Susilawati and Mia U. Hasanah for the conference administration, and Dini Fitriani for financial management. We also thank the National Geographic Indonesia for its support via the Business to Business Collaboration Program. The conference photograph can be viewed in the PDF.

  11. The earth's forced nutations - Geophysical implications

    NASA Technical Reports Server (NTRS)

    Wahr, J. M.; De Vries, D.

    1990-01-01

    Theories of nutation are examined critically to develop an extension of the theoretical description based on an earth in nonhydrostatic equilibrium. The estimation of nutation amplitude as a function of frequency is reviewed with reference to contributing variables such as the oceans, mantle anelasticity, and nonhydrostatic structure. Theoretical results by Wahr (1981) are compared to those of VLBI observations, and other VLBI data are used to discuss Wahr and Bergen's (1986) theoretical nutation admittances for an anelastic earth. The contributions associated with the tilt-over mode and with free-core nutations (FCN) are discussed, and the contribution of anelasticity is examined. The VLBI data show that nutation data are important sources of information regarding the earth's interior. Nutation amplitudes are derived with a model for a nonhydrostatically prestressed earth to determine the FCN contributions.

  12. Geophysics-based method of locating a stationary earth object

    DOEpatents

    Daily, Michael R.; Rohde, Steven B.; Novak, James L.

    2008-05-20

    A geophysics-based method for determining the position of a stationary earth object uses the periodic changes in the gravity vector of the earth caused by the sun- and moon-orbits. Because the local gravity field is highly irregular over a global scale, a model of local tidal accelerations can be compared to actual accelerometer measurements to determine the latitude and longitude of the stationary object.

  13. Exploring the geophysical signatures of microbial processes in the earth

    SciTech Connect

    Slater, L.; Atekwana, E.; Brantley, S.; Gorby, Y.; Hubbard, S. S.; Knight, R.; Morgan, D.; Revil, A.; Rossbach, S.; Yee, N.

    2009-05-15

    AGU Chapman Conference on Biogeophysics; Portland, Maine, 13-16 October 2008; Geophysical methods have the potential to detect and characterize microbial growth and activity in subsurface environments over different spatial and temporal scales. Recognition of this potential has resulted in the development of a new subdiscipline in geophysics called 'biogeophysics,' a rapidly evolving Earth science discipline that integrates environmental microbiology, geomicrobiology, biogeochemistry, and geophysics to investigate interactions that occur between the biosphere (microorganisms and their products) and the geosphere. Biogeophysics research performed over the past decade has confirmed the potential for geophysical techniques to detect microbes, microbial growth/biofilm formation, and microbe-mineral interactions. The unique characteristics of geophysical data sets (e.g., noninvasive data acquisition, spatially continuous properties retrieved) present opportunities to explore geomicrobial processes outside of the laboratory, at unique spatial scales unachievable with microbiological techniques, and possibly in remote environments such as the deep ocean. In response to this opportunity, AGU hosted a Chapman Conference with a mission to bring together geophysicists, biophysicists, geochemists, geomicrobiologists, and environmental microbiologists conducting multidisciplinary research with potential impact on biogeophysics in order to define the current state of the science, identify the critical questions facing the community, and generate a road map for establishing biogeophysics as a critical subdiscipline of Earth science research. For more information on the conference, see http://www.agu.org/meetings/chapman/2008/fcall/.

  14. Studies in geophysics: The Earth's electrical environment

    NASA Technical Reports Server (NTRS)

    1986-01-01

    The Earth is electrified. Between the surface and the outer reaches of the atmosphere, there is a global circuit that is maintained by worldwide thunderstorm activity and by upper atmospheric dynamo processes. The highest voltages approach a billion volts and are generated within thunderclouds, where lightning is a visual display of the cloud's electrical nature. The largest currents in the circuit, approaching a million amperes, are associated with the aurora. Because there have been significant advances in understanding many of the component parts of the global electric circuit (lightning, cloud electrification, electrical processes in specific atmospheric regions, and telluric currents), a principal research challenge is to understand how these components interact to shape the global circuit. Increased basic understanding in this field has many potential practical applications, including lightning protection, the design of advanced aircraft and spacecraft, and improvements in weather prediction.

  15. The solid earth: An introduction to global geophysics

    SciTech Connect

    Fowler, C.M.R.

    1990-01-01

    This book addresses major topics to be presented in a modern overview course. These topics include terrestrial seismology, gravity, earth's magnetic field and paleomagnetism, radiometric age dating, and heat flow. All are related throughout to the structure and dynamics of the interior of the earth, plate tectonics (including the geometry of tectonics on a sphere), and the nature of the continental and into such aspects as reflection coefficients and Zoeppritz equations, velocity analysis, migration, and Fresnel zone limitation on resolution. Appendices treat the elastic wave equations, inversion of earthquake time-distance curves, and a glossary of geological and geophysical terms. After noting that the book is intended for both geologists and physicists, as well as those marrying the disciplines into geophysics, the author adds that most geophysicists look for oil.

  16. The Environmental Movement: Beyond Earth Day.

    ERIC Educational Resources Information Center

    Baker, Beth

    1995-01-01

    This collection of articles looks at the history of Earth Day and the future of the environmental movement and environmental organizations. Examines reasons environmental organizations are losing support while the public remains committed to the environment. (LZ)

  17. The Earth surface slide movement at Soledad

    NASA Astrophysics Data System (ADS)

    Moreno, A.

    1986-11-01

    The Earth surface slide movement at Soledad is a mountain-slide type of movement. Estimations of the thickness of the layer which is moving range between 10 and 100 m. There is no proof that the movement is water induced, but it could be influenced by the water household. The slope of the slide area is H: D = 1: 2. The height difference in the moving area studied, according to this paper, is 1 km. The actual rate of movement is about 12 cm/yr.

  18. Geophysical, petrological and mineral physics constraints on Earth's surface topography

    NASA Astrophysics Data System (ADS)

    Guerri, Mattia; Cammarano, Fabio; Tackley, Paul J.

    2015-04-01

    Earth's surface topography is controlled by isostatically compensated density variations within the lithosphere, but dynamic topography - i.e. the topography due to adjustment of surface to mantle convection - is an important component, specially at a global scale. In order to separate these two components it is fundamental to estimate crustal and mantle density structure and rheological properties. Usually, crustal density is constrained from interpretation of available seismic data (mostly VP profiles) based on empirical relationships such those in Brocher [2005]. Mantle density structure is inferred from seismic tomography models. Constant coefficients are used to interpret seismic velocity anomalies in density anomalies. These simplified methods are unable to model the effects that pressure and temperature variations have on mineralogical assemblage and physical properties. Our approach is based on a multidisciplinary method that involves geophysical observables, mineral physics constraints, and petrological data. Mantle density is based on the thermal interpretation of global seismic tomography models assuming various compositional structures, as in Cammarano et al. [2011]. We further constrain the top 150 km by including heat-flow data and considering the thermal evolution of the oceanic lithosphere. Crustal density is calculated as in Guerri and Cammarano [2015] performing thermodynamic modeling of various average chemical compositions proposed for the crust. The modeling, performed with the code PerpleX [Connolly, 2005], relies on the thermodynamic dataset from Holland and Powell [1998]. Compressional waves velocity and crustal layers thickness from the model CRUST 1.0 [Laske et al., 2013] offer additional constrains. The resulting lithospheric density models are tested against gravity (GOCE) data. Various crustal and mantle density models have been tested in order to ascertain the effects that uncertainties in the estimate of those features have on the

  19. Geophysics: The Earth in Space. A Guide for High School Students.

    ERIC Educational Resources Information Center

    American Geophysical Union, Washington, DC.

    Geophysics is the application of physics, chemistry, and mathematics to the problems and processes of the earth, from its innermost core to its outermost environs in space. Fields within geophysics include the atmospheric sciences; geodesy; geomagnetism and paleomagnetism; hydrology; oceanography; planetology; seismology; solar-planetary…

  20. Geophysics: The Earth in Space. A Guide for High School Students.

    ERIC Educational Resources Information Center

    American Geophysical Union, Washington, DC.

    Geophysics is the application of physics, chemistry, and mathematics to the problems and processes of the earth, from its innermost core to its outermost environs in space. Fields within geophysics include the atmospheric sciences; geodesy; geomagnetism and paleomagnetism; hydrology; oceanography; planetology; seismology; solar-planetary…

  1. Polish Geophysical Solid Earth Infrastructure Contributing to EPOS

    NASA Astrophysics Data System (ADS)

    Debski, W.; Mutke, G.; Suchcicki, J.; Jozwiak, W.; Wiejacz, P.; Trojanowski, J.

    2012-04-01

    In this poster we present the current state of the main polish solid-earth-orientated infrastructures and shortly described history of their development, current state, and some plans for their future development. The presen- tation concentrates only on the classical infrastructure leaving aside for the while the the geodetic-orientated infrastructure, like GPS network and the GPS processing data centers, gravimetric infrastructure and others of this type. Polish broadband seismic infrastructure consists of 7 permanent broadband stations incorporated into the VEBSN initiative running at the polish territory and one operated in collaboration with NORSAR is settled at the Hornsund (Svalbard) polish polar station. All stations are equipped with STS-2 seismometers and polish MK-6 seismic stations providing 120 dB dynamics 100Hz sampling and data transmission in a real time to processing center. Besides this permanent broadband seismic network (PLSN) the Central Institute of Mining is running the permanent regional, short period network at the Upper Silesia area dedicated to the detailed monitoring of seismicity induced by the black coal mining activity in this area. The network consists of As the mining activity is the main source of seismicity in Poland also all mines are running underground short period networks, like for example Rudna-Polkowice copper mine seismic network consisting of 64 underground located short period seimometers. In that area, especially around the Zelazny Most: the huge post-floating artificial lake the, IGF PAS is running the local seismic array consisting of 4 short period seismometers. Besides these permanent network IGF PAN is running the portable seismic network for detailed mapping a possible natural seismic activity in selected regions of Poland. Important contribution to classical geophysical observation in the electro-magnetic field are provided by three permanent geomagnetic observatories (one at Hornsund) and supporting set of 10

  2. Geophysical Techniques for Monitoring CO2 Movement During Sequestration

    SciTech Connect

    Erika Gasperikova; G. Michael Hoversten

    2005-11-15

    The relative merits of the seismic, gravity, and electromagnetic (EM) geophysical techniques are examined as monitoring tools for geologic sequestration of carbon dioxide (CO{sub 2}). This work does not represent an exhaustive study, but rather demonstrates the capabilities of a number of geophysical techniques for two synthetic modeling scenarios. The first scenario represents combined CO{sub 2} enhanced oil recovery (EOR) and sequestration in a producing oil field, the Schrader Bluff field on the north slope of Alaska, USA. EOR/sequestration projects in general and Schrader Bluff in particular represent relatively thin injection intervals with multiple fluid components (oil, hydrocarbon gas, brine, and CO{sub 2}). This model represents the most difficult end member of a complex spectrum of possible sequestration scenarios. The time-lapse performance of seismic, gravity, and EM techniques are considered for the Schrader Bluff model. The second scenario is a gas field that in general resembles conditions of Rio Vista reservoir in the Sacramento Basin of California. Surface gravity, and seismic measurements are considered for this model.

  3. Applied geophysical techniques to evaluate earth dams and foundations

    NASA Astrophysics Data System (ADS)

    Llopis, Jose L.; Sharp, Michael K.; Butler, Dwain K.; Yule, Donald E.

    1995-05-01

    Mill Creek Dam, near Walla Walla, Washington has experienced anomalous seepage since its first filling in 1941. Various attempts to abate and control the seepage, including construction of a concrete wall, have not been completely successful. Construction of the cutoff wall reduced the seepage by about 30 percent, from 33 cubic feet per second to 22 cubic feet per second, and downstream saturated farmland was reduced by 56 percent. However, there are indications of increased seepage pressures in a conglomerate formation in the right abutment. A comprehensive, integrated geophysics investigation of the right abutment area of the dam was conducted to detect and map anomalous conditions and assist in the evaluation of remedial measures. The geophysics program consisted of microgravity, ground penetrating radar, seismic reflection, electromagnetic conductivity, and electrical resistivity surveying. Results of the program indicate anomalous conditions extending from the reservoir area through the right abutment. The aspects of the program planning leading to technique selection and field procedures are emphasized, as well as the role of different geophysical techniques in defining the nature of anomalous condition.

  4. Prospect of Continuous VLBI Measurement of Earth Rotation in Monitoring Geophysical Fluids

    NASA Technical Reports Server (NTRS)

    Chao, Benjamin F.; Ma, Chopo; Clark, Thomas

    1998-01-01

    Large-scale mass transports in the geophysical fluids of the Earth system excite Earth's rotational variations in both length-of-day and polar motion. The excitation process is via the conservation of angular momentum. Therefore Earth rotation observations contain information about the integrated angular momentum (consisting of both the mass term and the motion term) of the geophysical fluids, which include atmosphere, hydrosphere, mantle, and the outer and inner cores. Such global information is often important and otherwise unattainable depending on the nature of the mass transport, its magnitude and time scale. The last few years have seen great advances in VLBI measurement of Earth rotation in precision and temporal resolution. These advances have opened new. areas in geophysical fluid studies, such as oceanic tidal angular momentum, atmospheric tides, Earth librations, and rapid atmospheric angular momentum fluctuations. Precision of 10 microseconds in UTI and 200 microarcseconds in polar motion can now be achieved on hourly basis. Building upon this heritage, the multi-network geodetic VLBI project, Continuous Observation of the Rotation of the Earth (CORE), promises to further these studies and to make possible studies on elusive but tell-tale geophysical processes such as oscillatory modes in the core and in the atmosphere. Currently the early phase of CORE is underway. Within a few years into the new mellinnium, the upcoming space gravity missions (such as GRACE) will measure the temporal variations in Earth's gravitational field, thus providing complementary information to that from Earth rotation study for a better understanding of global geophysical fluid processes.

  5. Geophysical tomography for imaging water movement in welded tuff

    SciTech Connect

    Daily, W.D.; Ramirez, A.L.

    1986-09-01

    Alterant tomography has been evaluated for its ability to delineate in-situ water flow paths in a fractured welded-tuff rock mass. The evaluation involved a field experiment in which tomographs of electromagnetic attenuation factor (or attenuation rate) at 300 MHz were made before, during, and after the introduction to the rock of two different water-based tracers: a plain water and dye solution, and salt water and dye. Alterant tomographs were constructed by subtracting, cell by cell, the attenuation factors derived from measurements before each tracer was added to the rock mass from the attenuation factors derived after each tracer was added. The alterant tomographs were compared with other evidence of water movement in the rock: borescope logs of fractures, and post experiment cores used to locate the dye tracer on the fractured surfaces. These comparisons indicate that alterant tomography is suitable for mapping water flow through fractures and that it may be useful in inferring which of the fractures are hydrologically connected in the image plane. The technique appears to be sensitive enough to delineate flow through a single fracture and to define fractures with a spatial resolution of about 10 cm on an imaging scale of a few meters. 9 refs., 3 figs.

  6. Geophysical tomography for imaging water movement in welded tuff

    SciTech Connect

    Daily, W.; Ramirez, A.

    1986-09-01

    Alterant tomography has been evaluated for its ability to delineate in-situ water flow paths in a fractured welded-tuff rock mass. The evaluation involved a field experiment in which tomographs of electromagnetic attenuation factor (or attenuation rate) at 300 MHZ were made before, during, and after the introduction to the rock of two different water-based tracers: a plain water and dye solution, and salt water and dye. Alterant tomographs were constructed by subtracting, cell by cell, the attenuation factors derived from measurements before each tracer was added to the rock mass from the attenuation factors derived after each tracer was added. The alterant tomographs were compared with other evidence of water movement in the rock: borescope logs of fractures, and postexperiment cores used to locate the dye tracer on the fractured surfaces. These comparisons indicate that alterant tomography is suitable for mapping water flow through fractures and that it may be useful in inferring which of the fractures are hydrologically connected in the image plane. The technique appears to be sensitive enough to delineate flow through a single fracture and to define fractures with a spatial resolution of about 10 cm on an imaging scale of a few meters. 9 refs., 3 figs.

  7. Refining 3D Earth models by unifying geological and geophysical information on unstructured meshes

    NASA Astrophysics Data System (ADS)

    Lelièvre, P. G.; Carter-McAuslan, A.; Tycholiz, C.; Farquharson, C. G.; Hurich, C. A.

    2012-04-01

    Earth models used for mineral exploration or other subsurface investigations should be consistent with all available geological and geophysical information. Geophysical inversion provides the means to integrate geological information, geophysical survey data, and physical property measurements taken on rock samples. Incorporation of geological information into inversions is always an iterative process. One begins with the geologists' best guess about the Earth (i.e. the geological model) and the models recovered from geophysical inversion may indicate that the geological model should be changed slightly prior to the next iteration of the procedure. In this way, geological and geophysical data can be combined through inversion and we can move towards the creation of a common Earth model consistent with all the available data. As more information is incorporated, the inherent non-uniqueness of the inverse problem is reduced, yielding a higher potential to resolve deeper features that are less well-constrained by the geophysical data alone. Geological ore deposit models are commonly created during delineation drilling. The accuracy of these models is crucial when used to determine if a deposit is economic. 3D geological Earth models typically comprise wireframe surfaces that represent the geological contacts between different rock units. The contacts may be known at points from down-hole intersections and surface mapping, and can be interpolated between boreholes and extrapolated outwards. Contacts may also be interpreted from seismic traces. Wireframe surfaces, comprising tessellated triangular facets, are sufficiently flexible to allow the representation of arbitrarily complicated geological structures. These surfaces can be honoured exactly within fully unstructured 3D volumetric tetrahedral meshes. In contrast, geophysical forward modelling and inversion algorithms typically work with rectilinear meshes when parameterizing the subsurface because this simplifies

  8. At quadrennial geophysics fest, earth scientists think globally

    SciTech Connect

    Kerr, R.A.

    1995-07-28

    This article focuses on two areas of current research interest from the International Union of Geodesy and Geophysics meeting in July 1995. The first is the possible long and unlikely seeming change of connections. Linked are the warm surface of the tropical Pacific Ocean, the atmosphere at the midlatitudes in the Southern Hemisphere and the icy stratosphere over Antarctica where the warming of the sea surface 15 years ago may have set the stage for the Antarctic ozone hole. The second major research research reviewed concerned increases in ultraviolet light. Surface radiation in the DNA-damaging region of the spectrum is increasing by as much as 12% per decade at high latitudes.

  9. Geophysics

    NASA Technical Reports Server (NTRS)

    Carr, M. H.; Cassen, P.

    1976-01-01

    Four areas of investigation, each dealing with the measurement of a particular geophysical property, are discussed. These properties are the gravity field, seismicity, magnetism, and heat flow. All are strongly affected by conditions, past or present, in the planetary interior; their measurement is the primary source of information about planetary interiors.

  10. Earth's mantle composition and thermal state - A geophysical perspective.

    NASA Astrophysics Data System (ADS)

    Khan, A.

    2011-12-01

    We jointly invert local fundamental-mode and higher-order surface-wave phase-velocities for radial models of the thermo-chemical and anisotropic physical structure of the Earth's mantle to ~1000 km depth beneath the North American continent. Inversion for thermo-chemical state relies on a self-consistent thermodynamic method whereby phase equilibria and physical properties (P-, S-wave velocity and density) are computed as functions of composition (in the Na2O-CaO-FeO-MgO-Al2O3-SiO2 model system), pressure and temperature. We employ a sampling-based strategy to solve the non-linear inverse problem from which a range of models fitting the observations within uncertainties are obtained. Our thermo-chemical maps reveal the tectonically stable older eastern parts of North America to be chemically depleted (high Mg#) and colder (>200 deg C) relative to the active younger regions (western margin and oceans). In the transition zone the thermo-chemical structure decouples from that of the upper mantle, with a relatively hot thermal anomaly appearing beneath the cratonic area that likely extends into the lower mantle. In the lower mantle no consistent large-scale thermo-chemical heterogeneities are observed, although our results do suggest distinct upper and lower mantle compositions.

  11. Investigation of novel geophysical techniques for monitoring CO2 movement during sequestration

    SciTech Connect

    Hoversten, G. Michael; Gasperikova, Erika

    2003-10-31

    Cost effective monitoring of reservoir fluid movement during CO{sub 2} sequestration is a necessary part of a practical geologic sequestration strategy. Current petroleum industry seismic techniques are well developed for monitoring production in petroleum reservoirs. The cost of time-lapse seismic monitoring can be born because the cost to benefit ratio is small in the production of profit making hydrocarbon. However, the cost of seismic monitoring techniques is more difficult to justify in an environment of sequestration where the process produces no direct profit. For this reasons other geophysical techniques, which might provide sufficient monitoring resolution at a significantly lower cost, need to be considered. In order to evaluate alternative geophysical monitoring techniques we have undertaken a series of numerical simulations of CO{sub 2} sequestration scenarios. These scenarios have included existing projects (Sleipner in the North Sea), future planned projects (GeoSeq Liberty test in South Texas and Schrader Bluff in Alaska) as well as hypothetical models based on generic geologic settings potentially attractive for CO{sub 2} sequestration. In addition, we have done considerable work on geophysical monitoring of CO{sub 2} injection into existing oil and gas fields, including a model study of the Weyburn CO{sub 2} project in Canada and the Chevron Lost Hills CO{sub 2} pilot in Southern California (Hoversten et al. 2003). Although we are specifically interested in considering ''novel'' geophysical techniques for monitoring we have chosen to include more traditional seismic techniques as a bench mark so that any quantitative results derived for non-seismic techniques can be directly compared to the industry standard seismic results. This approach will put all of our finding for ''novel'' techniques in the context of the seismic method and allow a quantitative analysis of the cost/benefit ratios of the newly considered methods compared to the traditional

  12. Analysing the Orbital Movement and Trajectory of LEO (Low Earth Orbit) Satellite Relative to Earth Rotation

    NASA Astrophysics Data System (ADS)

    Bohra, Nafeesa; de Meer, Hermann; Memon, Aftab. A.

    Next generation of wireless Internet scenarios include LEOs (Low Earth Orbit Satellites). Lower altitudes of LEO constellations could allow global coverage while offering: low end-to-end propagation delay, low power consumption, and effective frequency usage both for the users and the satellite network. LEOs rotate asynchronously to the earth rotation. Fast movement of LEOs makes it necessary to include efficient mobility management. In past few years mobility patterns have been proposed by considering the full earth coverage constellation whereby, the rotation of earth was often assumed too negligible to be taken into account. The prime objective of this study is to provide facts and figures that show LEOs traverse relative to the rotation of earth. In order to analyse the orbital movement and trajectory of LEOs relative to earth rotation mathematical analysis have been done and justification have been made through equations.

  13. The SISMA prototype system: integrating Geophysical Modeling and Earth Observation for time dependent seismic hazard assessment

    NASA Astrophysics Data System (ADS)

    Peresan, A.; Panza, G. F.; Sabadini, R.; Barzaghi, R.; Amodio, A.; Bianco, G.

    2009-12-01

    A new approach to seismic hazard assessment is illustrated that, based on the available knowledge of the physical properties of the Earth structure and of seismic sources, as well as on the geophysical forward modeling, allows for a time dependent definition of the seismic input. According to the proposed approach, a fully formalized system integrating Earth Observation data and new advanced methods in seismological and geophysical data analysis, is currently under development in the framework of the Pilot Project SISMA, funded by the Italian Space Agency (ASI). The synergic use of geodetic Earth Observation data (EO) and Geophysical Forward Modeling (GFM) deformation maps at the national scale complements the space and time dependent information provided by real-time monitoring of seismic flow (performed by means of the earthquake prediction algorithms CN and M8S), so as to permit the identification and routine updating of alerted areas. At the small spatial scale (tens of km) of the seismogenic nodes identified by pattern recognition analysis, both GNSS (Global Navigation Satellite System) and SAR (Synthetic Aperture Radar) techniques, coupled with expressly developed models for inter-seismic phases, allow us to retrieve the deformation style and stress evolution within the seismogenic areas. The displacements fields obtained from EO data provide the input for the geophysical modeling, which permits to indicate whether a specific fault is in a "critical state". The scenarios of expected ground motion, associated with the alerted areas are then defined by means of full waveforms modeling, based on the possibility to compute synthetic seismograms by the modal summation technique. In this way a set of deterministic scenarios of ground motion, which refers to the time interval when a strong event is likely to occur within the alerted area, can be defined either at national and local scale. The considered integrated approach opens new routes in understanding the

  14. Expanding Earth and declining gravity: a chapter in the recent history of geophysics

    NASA Astrophysics Data System (ADS)

    Kragh, H.

    2015-05-01

    Although speculative ideas of an expanding Earth can be found before World War II, it was only in the 1950s and 1960s that the theory attracted serious attention among a minority of earth scientists. While some of the proponents of the expanding Earth adopted an empiricist attitude by disregarding the physical cause of the assumed expansion, others argued that the cause, either fully or in part, was of cosmological origin. They referred to the possibility that the gravitational constant was slowly decreasing in time, as first suggested by P. Dirac in 1937. As a result of a stronger gravitation in the past, the ancient Earth would have been smaller than today. The gravitational argument for an expanding Earth was proposed by P. Jordan and L. Egyed in the 1950s and during the next 2 decades it was discussed by several physicists, astronomers and earth scientists. Among those who for a period felt attracted by "gravitational expansionism" were A. Holmes, J. Tuzo Wilson and F. Hoyle. The paper examines the idea of a varying gravitational constant and its impact on geophysics in the period from about 1955 to the mid-1970s.

  15. Halogen and phosphorus storage in the earth. [elemental spatial distribution from geochemical, geophysical, and cosmochemical factors

    NASA Technical Reports Server (NTRS)

    Smith, J. V.

    1981-01-01

    Chemical analyses of surface reservoirs, coupled with compositions for interior zones inferred from geophysical and geochemical data have been used to obtain a range of estimates of the bulk composition of the earth. It is suggested that (1) apatite with 3 wt% Fe, up to 1 wt% Cl, and 0.003 wt% Br is the principal mineral reservoir for halogens, and mica is a subsidiary reservoir; (2) apatite with 18 wt% P is the principal store of P in the upper mantle and perhaps lower mantle, but accounts for only one-twentieth of P in the earth; and (3) the remaining P is in a reservoir inaccessible to magmatism, and may amount to a maximum of 0.7 wt% in the core.

  16. Halogen and phosphorus storage in the earth. [elemental spatial distribution from geochemical, geophysical, and cosmochemical factors

    NASA Technical Reports Server (NTRS)

    Smith, J. V.

    1981-01-01

    Chemical analyses of surface reservoirs, coupled with compositions for interior zones inferred from geophysical and geochemical data have been used to obtain a range of estimates of the bulk composition of the earth. It is suggested that (1) apatite with 3 wt% Fe, up to 1 wt% Cl, and 0.003 wt% Br is the principal mineral reservoir for halogens, and mica is a subsidiary reservoir; (2) apatite with 18 wt% P is the principal store of P in the upper mantle and perhaps lower mantle, but accounts for only one-twentieth of P in the earth; and (3) the remaining P is in a reservoir inaccessible to magmatism, and may amount to a maximum of 0.7 wt% in the core.

  17. Melting and melt-movement in the Earth

    NASA Astrophysics Data System (ADS)

    White, Robert S.

    Researchers came together to discuss melting and melt-movement in the Earth at a 2-day Royal Society Discussion Meeting held in March 1992 at the Royal Society, London.In recent years, many new tools have become available to geologists studying igneous and metamorphic rocks. They can be examined at ever-higher magnifications: the composition within individual crystals can be measured; their isotopic, trace, and rare-earth element concentrations can be determined; and measurements of partition coefficients and melting behavior can be made in the laboratory at pressures and temperatures appropriate to in-situ rocks. Along with these improvements in instrumentation and experimental techniques, advances have been made in understanding the physics of melt generation and separation, and computers have been developed that are sufficiently powerful to model theoretical formulations of the behavior of melt in the Earth.

  18. 7 CFR 330.302 - Domestic movements of earth (including soil), stone, etc.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 5 2010-01-01 2010-01-01 false Domestic movements of earth (including soil), stone... Products § 330.302 Domestic movements of earth (including soil), stone, etc. The interstate movement from regulated areas in the Continental United States of earth (including soil), stone, quarry products,...

  19. 7 CFR 330.302 - Domestic movements of earth (including soil), stone, etc.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 5 2012-01-01 2012-01-01 false Domestic movements of earth (including soil), stone... Products § 330.302 Domestic movements of earth (including soil), stone, etc. The interstate movement from regulated areas in the Continental United States of earth (including soil), stone, quarry products,...

  20. 7 CFR 330.302 - Domestic movements of earth (including soil), stone, etc.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 5 2013-01-01 2013-01-01 false Domestic movements of earth (including soil), stone... Products § 330.302 Domestic movements of earth (including soil), stone, etc. The interstate movement from regulated areas in the Continental United States of earth (including soil), stone, quarry products,...

  1. 7 CFR 330.302 - Domestic movements of earth (including soil), stone, etc.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 5 2011-01-01 2011-01-01 false Domestic movements of earth (including soil), stone... Products § 330.302 Domestic movements of earth (including soil), stone, etc. The interstate movement from regulated areas in the Continental United States of earth (including soil), stone, quarry products,...

  2. 7 CFR 330.302 - Domestic movements of earth (including soil), stone, etc.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 5 2014-01-01 2014-01-01 false Domestic movements of earth (including soil), stone... Products § 330.302 Domestic movements of earth (including soil), stone, etc. The interstate movement from regulated areas in the Continental United States of earth (including soil), stone, quarry products,...

  3. Discover Our Earth: Web-Based Geophysical Data in the Classroom

    NASA Astrophysics Data System (ADS)

    Moore, A.; Seber, D.; Danowski, D.; Brindisi, C.

    2002-12-01

    Discover Our Earth is a web-based system designed for classroom use, allowing access and display of geospatial data sets . It is an education and outreach module built as part of Cornell University's Geoscience Information System, originally constructed as a tool for geophysical research (http://atlas.geo.cornell.edu). Discover Our Earth has been used in university, high school and middle school classrooms. Working with real data is a powerful tool for helping students learn scientific principles, content, and the processes of scientific inquiry. In order to give students access to data that is otherwise difficult to work with, Discover Our Earth is comprised of several elements. The central component is a Java applet called QUEST (Quick Use Earth Study Tool). QUEST allows students to query and display data from three data sets selected from the 100+ housed within the Information System. Any attribute of earthquake, volcano, or topographic data can be selected and displayed, and multiple data sets can be overlain on each other, or on assorted background images (such as a geographic base map, age of the sea floor etc). Each image is saved in the QUEST history window, allowing students to compare multiple selections, or to animate a series of images as a "filmstrip." In order to help students better understand their results, the QUEST applet is supported by several other components. There are guides for both teacher and student. The student guide gives step-by-step instructions for a series of problems, and suggests others that will help students answer questions of local and global interest. The teacher guide provides background material, context, and answers to the student exercises. There are animations and 3-D visualizations that allow students to better interpret their maps. Additionally, there are interactive experiments on topics such as continental drift, isostasy, viscosity, that allow students to explore the physics that underlie the processes they are

  4. Towards a better understanding of the Earth's interior and geophysical exploration research "GOCE-GDC"

    NASA Astrophysics Data System (ADS)

    Novak, P.; Baur, O.; Martinec, Z.; Sneeuw, N.; Tsoulis, D.; Vermeersen, B.; van der Wal, W.; Roth, M.; Sebera, J.; Valko, M.; Hoeck, E.

    2012-04-01

    Within the ESA STSE: GOCE+ Theme 2 a consortium of researchers from 6 European institutes investigates applications of GOCE gravity gradients in order to improve geophysical models in two different geographical areas. The first area, the Reykjanes Ridge close to Iceland, covers a mid-ocean ridge that plays a key role for creation of a new crust and for generation of ridge push driving partly plate motion. GOCE gravity gradients will be used for refined local density modelling that cannot uniquely be achieved through seismic measurements. In Africa, the second test area of the project, GOCE gravity gradients will be combined with seismic tomographic models of the continental lithospheric mantle (upper 200 km or so of the Earth's mantle that lies beneath the thin crustal layer) in order to refine an initial density model derived by 3-D modelling programs. To achieve these goals, GOCE gravity gradients will be used in combination with other available data sources such ground and marine gravity, altimetry, terrain elevation and density models, seismic tomographic and mantle flow models and crustal thickness models. However, the main target for the project is to demonstrate in particular benefits of GOCE gravity gradients for geophysical applications and interpretations.

  5. Observation of the Earth's nutation by the VLBI: how accurate is the geophysical signal

    NASA Astrophysics Data System (ADS)

    Gattano, César; Lambert, Sébastien B.; Bizouard, Christian

    2016-09-01

    We compare nutation time series determined by several International VLBI Service for geodesy and astrometry (IVS) analysis centers. These series were made available through the International Earth Rotation and Reference Systems Service (IERS). We adjust the amplitudes of the main nutations, including the free motion associated with the free core nutation (FCN). Then, we discuss the results in terms of physics of the Earth's interior. We find consistent FCN signals in all of the time series, and we provide corrections to IAU 2000A series for a number of nutation terms with realistic errors. It appears that the analysis configuration or the software packages used by each analysis center introduce an error comparable to the amplitude of the prominent corrections. We show that the inconsistencies between series have significant consequences on our understanding of the Earth's deep interior, especially for the free inner core resonance: they induce an uncertainty on the FCN period of about 0.5 day, and on the free inner core nutation (FICN) period of more than 1000 days, comparable to the estimated period itself. Though the FCN parameters are not so much affected, a 100 % error shows up for the FICN parameters and prevents from geophysical conclusions.

  6. Observation of the Earth's nutation by the VLBI: how accurate is the geophysical signal

    NASA Astrophysics Data System (ADS)

    Gattano, César; Lambert, Sébastien B.; Bizouard, Christian

    2017-07-01

    We compare nutation time series determined by several International VLBI Service for geodesy and astrometry (IVS) analysis centers. These series were made available through the International Earth Rotation and Reference Systems Service (IERS). We adjust the amplitudes of the main nutations, including the free motion associated with the free core nutation (FCN). Then, we discuss the results in terms of physics of the Earth's interior. We find consistent FCN signals in all of the time series, and we provide corrections to IAU 2000A series for a number of nutation terms with realistic errors. It appears that the analysis configuration or the software packages used by each analysis center introduce an error comparable to the amplitude of the prominent corrections. We show that the inconsistencies between series have significant consequences on our understanding of the Earth's deep interior, especially for the free inner core resonance: they induce an uncertainty on the FCN period of about 0.5 day, and on the free inner core nutation (FICN) period of more than 1000 days, comparable to the estimated period itself. Though the FCN parameters are not so much affected, a 100 % error shows up for the FICN parameters and prevents from geophysical conclusions.

  7. Using earthquakes to uncover the Earth's inner secrets: interactive exhibits for geophysical education

    NASA Astrophysics Data System (ADS)

    Nostro, C.; Cultrera, G.; Burrato, P.; Tertulliani, A.; Macrì, P.; Winkler, A.; Castellano, C.; Casale, P.; di Felice, F.; Doumaz, F.; Piscini, A.; Scarlato, P.; Vallocchia, M.; Marsili, A.; Badiali, L.; Bono, A.; Stramondo, S.; Alfonsi, L.; Baroux, E.; Ciaccio, M. G.; Frepoli, A.

    2005-06-01

    The Educational & Outreach Group (E&O Group) of the Istituto Nazionale di Geofisica e Vulcanologia (INGV) designed a portable museum to bring on the road educational activities focused on seismology, seismic hazard and Earth science. This project was developed for the first edition of the Science Festival organized in Genoa, Italy, in 2003. The museum has been mainly focused to school students of all ages and explains the main topics of geophysics through posters, movie and slide presentations, and exciting interactive experiments. This new INGV museum has been remarkably successful, being visited by more than 8000 children and adults during the 10 days of the Science Festival. It is now installed at the INGV headquarters in Rome and represents the main attraction during the visits of the schools all year round.

  8. Satellite-tracking and earth-dynamics research programs. [geodetic and geophysical investigations and atmospheric research using satellite drag data

    NASA Technical Reports Server (NTRS)

    1972-01-01

    Satellite tracking and earth dynamics research programs are discussed. Geodetic and geophysical investigations are reported along with atmospheric research using satellite drag data. Satellite tracking network functions and support groups which are discussed include: network operations, communications, data-services division, moonwatch, and programming group.

  9. Joining statistics and geophysics for assessment and uncertainty quantification of three-dimensional seismic Earth models

    DOE PAGES

    Larmat, Carene; Maceira, Monica; Higdon, David M.; ...

    2017-08-29

    Seismic inversions produce seismic models, which are 3-dimensional (3D) images of wave velocity of the entire planet retrieved by fitting seismic measurements made on records of past earthquakes or other seismic events. Computing power of the TeraFlop era, along with the dataflow from new, very dense, seismic arrays, has led to a new generation of 3D seismic Earth models with an unprecedented level of resolution. Here we compare two recent models of western United States from the Dynamic North America (DNA) seismic imaging effort. The two models only differ in the wave propagation that was used for their inversion: onemore » is based on ray theory (RT), and the other on finite frequency (FF). We evaluate the two models using an independent numerical method and statistical tests. We show that they differ in how they produce seismic signals from a subset of earthquakes that were used in the original inversion and were recorded on the US array. This is especially true for measurements done in the Yellowstone area which has a large negative seismic anomaly. This result is of importance for seismologists who have been debating on the practical benefit of using FF in ill-posed Earth inversions. Model evaluation, such as the one reported here, represents an opportunity for collaboration between geophysical and statistical communities. Finally, more opportunities should arise with the upcoming Exascale era, which will provide enough computational power to explore together several sources of errors in models with thousands of parameters, opening the way of uncertainty quantification of seismic models.« less

  10. FDSN and EarthCube: Coordinating Global Infrastructures within Seismology and Across Other Geophysical Domains

    NASA Astrophysics Data System (ADS)

    Ahern, T. K.; Ekstrom, G.; Grobbelaer, M.; Trabant, C. M.; Van Fossen, M.; Stults, M.; Tsuboi, S.; Beaudoin, B. C.; Bondar, I.

    2016-12-01

    Seismology, by its very nature, requires sharing information across international boundaries and as such seismology evolved as a science that promotes free and open access to data. The International Federation of Digital Seismograph Networks (FDSN) has commission status within IASPEI and as such is the international standards body in our community. In the late 1980s a domain standard for exchanging seismological information was created and the SEED format is still the dominant domain standard. More recently the FDSN standardized web-service interfaces for key services used in our community. The standardization of these services also enabled the development of a federation of data centers. These federated centers, can be accessed through standard FDSN service calls. Client software exists that currently allows seamless and transparent access to all data managed at 14 globally distributed data centers on three continents with plans to expand this more broadly. IRIS is also involved in the EarthCube project funded by the US National Science Foundation. The GEOphysical Web Services (GeoWS) project extended the style of web services endorsed by the FDSN to interdisciplinary domains. IRIS worked with five data centers in other domains (Caltech, UCSD, Columbia University, UNAVCO and Unidata) to develop `similar' service-based interfaces to their data systems that were drawn from the oceanographic, atmospheric, and solid earth divisions within the NSF's geosciences directorate. Additionally IRIS developed GeoWS style web services for six additional data collections that included magnetic observations, field gravity measurements, superconducting gravimetry data, volcano monitoring data, tidal data, and oceanographic observations including those from cabled arrays in the ocean. This presentation will highlight the success the FDSN and GeoWS services have demonstrated within and beyond seismology as well as identifying some next steps being considered.

  11. Development, Deployment, and Assessment of Dynamic Geological and Geophysical Models Using the Google Earth APP and API: Implications for Undergraduate Education in the Earth and Planetary Sciences

    NASA Astrophysics Data System (ADS)

    de Paor, D. G.; Whitmeyer, S. J.; Gobert, J.

    2009-12-01

    We previously reported on innovative techniques for presenting data on virtual globes such as Google Earth using emergent Collada models that reveal subsurface geology and geophysics. We here present several new and enhanced models and linked lesson plans to aid deployment in undergraduate geoscience courses, along with preliminary results from our assessment of their effectiveness. The new Collada models are created with Google SketchUp, Bonzai3D, and MeshLab software, and are grouped to cover (i) small scale field mapping areas; (ii) regional scale studies of the North Atlantic Ocean Basin, the Appalachian Orogen, and the Pacific Ring of Fire; and (iii) global scale studies of terrestrial planets, moons, and asteroids. Enhancements include emergent block models with three-dimensional surface topography; models that conserve structural orientation data; interactive virtual specimens; models that animate plate movements on the virtual globe; exploded 3-D views of planetary mantles and cores; and server-generated dynamic KML. We tested volunteer students and professors using Silverback monitoring software, think-aloud verbalizations, and questionnaires designed to assess their understanding of the underlying geo-scientific phenomena. With the aid of a cohort of instructors across the U.S., we are continuing to assess areas in which users encounter difficulties with both the software and geoscientific concepts. Preliminary results suggest that it is easy to overestimate the computer expertise of novice users even when they are content knowledge experts (i.e., instructors), and that a detailed introduction to virtual globe manipulation is essential before moving on to geoscience applications. Tasks that seem trivial to developers may present barriers to non-technical users and technicalities that challenge instructors may block adoption in the classroom. We have developed new models using the Google Earth API which permits enhanced interaction and dynamic feedback and

  12. Integrating Diverse Geophysical and Geological Data to Construct Multi-Dimensional Earth Models: The Open Earth Framework

    NASA Astrophysics Data System (ADS)

    Baru, C.; Keller, R.; Wallet, B.; Crosby, C.; Moreland, J.; Nadeau, D.

    2008-12-01

    Currently, many large geoscientific efforts (e.g., EarthScope, Continental Dynamics, and GeoSwath) have emphasized that a crucial need in advancing our understanding of the structure and evolution of the continents is high-resolution, 3-D models of lithospheric structure. In addition, the geoscience community recognizes that our ultimate goal is the addition of the dimension of time to make the problem 4-D. Adding the dimension of time is a complex problem that is strongly dependent on the integration of a variety of geological data into our analyses (e.g., geochronology, paleontology, stratigraphy, pressure-time histories, structural geology, paleogeography, etc.). The geoscience community also recognizes that solutions to the scientific and societal questions that they seek to answer require innovative integration of many types of data so that many physical properties (x, y, z, P-wave velocity, S-wave velocity, density, electrical conductivity, etc.) are measured and included in 3-D models. The problem is, therefore, truly multidimensional in nature. We are developing an Open Earth Framework (OEF) as an open data model for integration of such multidimensional Earth Sciences data. In our work and interactions with the community on building and visualizing complex earth models, several issues have emerged on which there is consensus. First of all, integration efforts should work from the surface down because we have the most data there (e.g., geologic maps, remote sensing data such as LIDAR and ASTER, digital elevation models, gravity and magnetic measurements, etc.) and because the complex conditions near surface always have a potential to mask deeper features. Secondly since we cannot expect uniform coverage of a variety of high-resolution data in anything but special circumstances, a data integration effort should first establish a regional context using lower resolution (and usually wide coverage) data and then proceed to modeling the data sets with the highest

  13. On Earth's Mantle Constitution and Structure from Joint Analysis of Geophysical and Laboratory-Based Data: An Example

    NASA Astrophysics Data System (ADS)

    Khan, Amir

    2016-01-01

    Determining Earth's structure is a fundamental goal of Earth science, and geophysical methods play a prominent role in investigating Earth's interior. Geochemical, cosmochemical, and petrological analyses of terrestrial samples and meteoritic material provide equally important insights. Complementary information comes from high-pressure mineral physics and chemistry, i.e., use of sophisticated experimental techniques and numerical methods that are capable of attaining or simulating physical properties at very high pressures and temperatures, thereby allowing recovered samples from Earth's crust and mantle to be analyzed in the laboratory or simulated computationally at the conditions that prevail in Earth's mantle and core. This is particularly important given that the vast bulk of Earth's interior is geochemically unsampled. This paper describes a quantitative approach that combines data and results from mineral physics, petrological analyses of mantle minerals, and geophysical inverse calculations, in order to map geophysical data directly for mantle composition (major element chemistry and water content) and thermal state. We illustrate the methodology by inverting a set of long-period electromagnetic response functions beneath six geomagnetic stations that cover a range of geological settings for major element chemistry, water content, and thermal state of the mantle. The results indicate that interior structure and constitution of the mantle can be well-retrieved given a specific set of measurements describing (1) the conductivity of mantle minerals, (2) the partitioning behavior of water between major upper mantle and transition-zone minerals, and (3) the ability of nominally anhydrous minerals to store water in their crystal structures. Specifically, upper mantle water contents determined here bracket the ranges obtained from analyses of natural samples, whereas transition-zone water concentration is an order-of-magnitude greater than that of the upper

  14. [The gravity field of the Earth: geophysical factor of gerontology (The Vorobeichikov effect)].

    PubMed

    Shapovalov, S N

    2016-01-01

    The results of investigations of the growth in vitro of Escherichia coli M-17, obtained in the processing of V. M. Vorobeichikov observational data during the movement of the scientific expedition ship «Akademik Fedorov» from St. Petersburg to Antarctica and back, in the period from 13.11.2002 on 26.05.2003 (48th Russian Antarctic expedition). The findings based on the growth in vitro of Escherichia coli from changes in geographical location on a planetary scale, that doesn't eliminate the dependence of other species of microorganisms from the spatial position in the gravity field of the Earth. It is established that the duration of the lag phase of Escherichia coli in the Equatorial zone close to its duration in the high-latitude zone and Antarctic, however, the duration of the lag phase at the equator and the Antarctic corresponds to the time of the lag phase at the time of the Central phase of the lunar Eclipse. The conclusion about high sensitivity in vitro of Escherichia coli to the field of gravity of the Earth, and to syzigium events.

  15. Whole earth modeling: developing and disseminating scientific software for computational geophysics.

    NASA Astrophysics Data System (ADS)

    Kellogg, L. H.

    2016-12-01

    Historically, a great deal of specialized scientific software for modeling and data analysis has been developed by individual researchers or small groups of scientists working on their own specific research problems. As the magnitude of available data and computer power has increased, so has the complexity of scientific problems addressed by computational methods, creating both a need to sustain existing scientific software, and expand its development to take advantage of new algorithms, new software approaches, and new computational hardware. To that end, communities like the Computational Infrastructure for Geodynamics (CIG) have been established to support the use of best practices in scientific computing for solid earth geophysics research and teaching. Working as a scientific community enables computational geophysicists to take advantage of technological developments, improve the accuracy and performance of software, build on prior software development, and collaborate more readily. The CIG community, and others, have adopted an open-source development model, in which code is developed and disseminated by the community in an open fashion, using version control and software repositories like Git. One emerging issue is how to adequately identify and credit the intellectual contributions involved in creating open source scientific software. The traditional method of disseminating scientific ideas, peer reviewed publication, was not designed for review or crediting scientific software, although emerging publication strategies such software journals are attempting to address the need. We are piloting an integrated approach in which authors are identified and credited as scientific software is developed and run. Successful software citation requires integration with the scholarly publication and indexing mechanisms as well, to assign credit, ensure discoverability, and provide provenance for software.

  16. Research Opportunities in Solid Earth Science (RESESS): Broadening Participation in Geology and Geophysics (Invited)

    NASA Astrophysics Data System (ADS)

    Eriksson, S. C.; Hubenthal, M.

    2009-12-01

    RESESS is a multi-year, paid, summer research internship program designed for students from underrepresented groups. The students receive extensive mentoring in science research and communication and become part of a community that provides ongoing support. This has been possible in the initial 5 years of the program through collaboration with Significant Opportunities in Atmospheric Research and Science (SOARS), where solid earth students have been an integral part of the SOARS cohort, benefiting from social as well as educational interactions. 11 students have taken part in RESESS for at least one year and of these, four students have graduated in geoscience and entered graduate programs in geophysics and one was recently awarded an NSF graduate fellowship. Students have presented over 20 posters at national science meetings, and one has co-authored a peer-reviewed article. 23 scientists have mentored students over the past 5 years and 17 percent of these mentors are from underrepresented groups in science; 19 other scientists and university/science consortia staff have mentored students in written and verbal presentations and supported their integration into the local communities. Mentorship over a period of years is one important hallmark of this program as students have benefited from the support of UNAVCO, IRIS, USGS, and university scientists and staff during the summer, academic year, and at professional meetings such as AGU, GSA, NABGG, and SACNAS as well as consortia and project science workshops (UNAVCO, IRIS, and EarthScope). One goal of the project has been to educate the scientific community on the benefits of mentoring undergraduate students from underrepresented groups in STEM fields. Increasingly, scientists are approaching RESESS to include this program in their implementation of broader impacts. RESESS has been funded by NSF for the next five years with plans to expand the number of students, geographic and scientific diversity, and sources of

  17. Geophysics of the solid earth, the moon and the planets. Subvolume a

    NASA Astrophysics Data System (ADS)

    Fuchs, K.; Soffel, H.

    Physical data on the earth as a solid body and on the moon and terrestrial planets are compiled in tables, maps, and diagrams. The theoretical bases of the measurements and the techniques employed in acquiring and processing the data are discussed in the accompanying text. Topics covered include the origin of the earth in the solar system; the motion of the earth; seismicity and the interior of the earth; heat flow, temperature distribution, electrical properties, and composition of the earth interior; tides; the gravity field and figure of the earth; the earth magnetic field; mass transport in the earth interior; and the planetology of the terrestrial planets.

  18. Particle Geophysics

    NASA Astrophysics Data System (ADS)

    Tanaka, Hiroyuki K. M.

    2014-05-01

    Geophysics research has long been dominated by classical mechanics, largely disregarding the potential of particle physics to augment existing techniques. The purpose of this article is to review recent progress in probing Earth's interior with muons and neutrinos. Existing results for various volcanological targets are reviewed. Geoneutrinos are also highlighted as examples in which the neutrino probes elucidate the composition of Earth's deep interior. Particle geophysics has the potential to serve as a useful paradigm to transform our understanding of Earth as dramatically as the X-ray transformed our understanding of medicine and the body.

  19. Assessing vulnerability to vegetation growth on earth dikes using geophysical investigation

    NASA Astrophysics Data System (ADS)

    Mary, Benjamin; Saracco, Ginette; Peyras, Laurent; Vennetier, Michel; Mériaux, Patrice

    2015-04-01

    The Mediterranean Basin is prone to a plethora of natural hazards including floods. Vegetation growth in hydraulic earth structures, such as flood protections or channel levees and dams, may induce several degradation mechanisms leading to a risk of failure. Typically, trees' rooting generates two types of risks: internal erosion from root development in earth embankments, and external erosion (slopes and crest) which is often related to trees uprooting. To better assess how woody vegetation can compromise levee integrity, we designed a methodology using acoustical and complex electrical tomography as non destructives methods to spot dangerous roots in the embankment. Our work has been first initiated during laboratory experiments; we performed soundings in controlled conditions to determine both acoustical and electrical intrinsic behavior of our root samples. By comparison with soil samples we expected to point out specific signatures that would be useful for the roots anomaly identification in real conditions. Measurements were repeated on several samples to ensure statistical interpretation. With help of an ultrasonic transmission device, we identified significant relative velocity differences of compressional waves propagation between soil and root samples. We also studied spectral properties using wavelet processing method as an additional parameter of root distinction with the surrounding soil. In the case of electrical soundings, complex resistivity was measured and we computed resistivity spectra. Amplitude of resistivity term showed us that root material behaves as an insulator compared to the soil. With the phase resistivity term information, root can also be seen as an electric power capacitance and reveals maximum polarization effect located around 1Hz. Then, as experimental device for the field measurements, we selected a 320 cm high poplar (Populus) planted in a homogeneous loamy-clayed soil, which is the same soil used in laboratory experiment to

  20. Geophysical disturbance environment during the NASA/MPE barium release at 5 earth radii on September 21, 1971.

    NASA Technical Reports Server (NTRS)

    Davis, T. N.; Stanley, G. M.; Boyd, J. S.

    1973-01-01

    The geophysical disturbance environment was quiet during the NASA/MPE barium release at 5 earth radii on September 21, 1971. At the time of the release, the magnetosphere was in the late recovery phase of a principal magnetic storm, the provisional Dst value was -13 gammas, and the local horizontal disturbance at Great Whale River was near zero. Riometer and other observations indicated low-level widespread precipitation of high-energy electrons at Great Whale River before, during, and after the release. Cloudy sky at this station prevented optical observation of aurora. No magnetic or ionospheric effects attributable to the barium release were detected at Great Whale River.

  1. Geophysical methods

    SciTech Connect

    Robert, E.S.

    1989-01-01

    Geophysical measurements involve no magic or mystery but straightforward applications of physical principles. This book is both a geophysical survey and a reference guide. It explains the physical principles involved in geophysical methods. Over one-third of the text is devoted to seismic methods. Comprehensive topics in the volume include: the measurement of different physical properties and their geological significance; how different kinds of measurements are combined to draw geological conclusions; surface, borehole, airborne, and satellite measurements; computer processing and interactive methods; geodetic, gravity, magnetic, radioactive, heat flow, and electrical methods; interpretation of natural processes such as earthquakes and heat flow; and a summation of present knowledge of the earth.

  2. Geophysical expression of a buried niobium and rare earth element deposit: the Elk Creek carbonatite, Nebraska, USA

    USGS Publications Warehouse

    Drenth, Benjamin J.

    2014-01-01

    The lower Paleozoic Elk Creek carbonatite is a 6–8-km-diameter intrusive complex buried under 200 m of sedimentary rocks in southeastern Nebraska. It hosts the largest known niobium deposit in the U.S. and a rare earth element (REE) deposit. The carbonatite is composed of several lithologies, the relations of which are poorly understood. Niobium mineralization is most enriched within a magnetite beforsite (MB) unit, and REE oxides are most concentrated in a barite beforsite unit. The carbonatite intrudes Proterozoic country rocks. Efforts to explore the carbonatite have used geophysical data and drilling. A high-resolution airborne gravity gradient and magnetic survey was flown over the carbonatite in 2012. The carbonatite is associated with a roughly annular vertical gravity gradient high and a subdued central low and a central magnetic high surrounded by magnetic field values lower than those over the country rocks. Geophysical, borehole, and physical property data are combined for an interpretation of these signatures. The carbonatite is denser than the country rocks, explaining the gravity gradient high. Most carbonatite lithologies have weaker magnetic susceptibilities than those of the country rocks, explaining why the carbonatite does not produce a magnetic high at its margin. The primary source of the central magnetic high is interpreted to be mafic rocks that are strongly magnetized and are present in large volumes. MB is very dense (mean density 3200  kg/m3) and strongly magnetized (median 0.073 magnetic susceptibility), producing a gravity gradient high and contributing to the aeromagnetic high. Barite beforsite has physical properties similar to most of the carbonatite volume, making it a poor geophysical target. Geophysical anomalies indicate the presence of dense and strongly magnetized rocks at depths below existing boreholes, either a large volume of MB or another unknown lithology.

  3. Assessing landslide movements in volcanic islands using near-shore marine geophysical data: south Pico island, Azores

    NASA Astrophysics Data System (ADS)

    Mitchell, N. C.; Quartau, R.; Madeira, J.

    2011-12-01

    Marine geophysical data can help to resolve whether large-scale instability of an edifice has been geologically recently active. We study such data from the coast of Pico Island where a major slump of Topo volcano has been interpreted from arcuate escarpments and a rugged irregular topography above sea-level. Multibeam sonar data collected immediately offshore show little evidence for slump fault movements, in particular on the island shelf. As the shelf rock platform will have been last modified by surf during the postglacial sea-level transgression, it provides a reference surface of intermediate age (7-19 ky) that can potentially reveal any pre-historic movements. Where the arcuate escarpments are continued offshore, no evidence for active faults are observed where the shelf rock platform crops out in the multibeam data. Elsewhere, mobile shelf sediments may disguise evidence for active faulting so we examined boomer profiles able to image the rock platform beneath them. The data reveal a platform that is steep (6.6 degrees) compared with the dips of platforms around the coast of adjacent Faial Island and steeper than the platform outside the proposed slump. This suggests that it was created by coastal erosion over a shorter period and hence is consistent with a younger coastline age. As with the multibeam data, where escarpments are continued offshore, the rock surface imaged with these boomer data also shows no clear evidence of major slump-related fault displacements. This study therefore illustrates how high-resolution boomer seismic and multibeam data could usefully contribute to hazard assessment of volcanic islands, by helping to evaluate areas with no historical movements.

  4. Earth's rotation variations effect the earthquake triggering and lithospheric plates movement

    NASA Astrophysics Data System (ADS)

    Ostrihansky, Lubor

    2013-04-01

    The first group of scientists claims that the headline stated above is quite absurd because the Earth's rotation variations exert the pressure only ~1 Pa on the lithosphere. The second group claims that the despinning of the axial Earth's rotation only influences not determines the plate motion and earthquake triggering. However the third possibility is correct. The Earth's rotation variations cause the earthquake triggering and the plate movement as many observations can prove. Comparison with neighboring planets shows that Mars has no plate movement owing to the absence of large tidal forming body and Venus has slow rotation and negligible flattening. It is not true that tidal forces acting on the Earth are insufficient. Tidal forces acting on the Earth's flattening cause sufficient northward directing torques acting on plates comparable in magnitudes with the seismic moments. The westward movement of plates is evident but its calculation is more difficult and it is necessary to suppose that both the acceleration and deceleration of the Earth's rotation cause the westward lithosphere movement. Many statistics prove the coincidence of earthquakes with semidiurnal tides as result of mid-ocean ridges formation owing to the material fatigue and by loading of waters in subduction zones. Coincidence of earthquakes with LOD variations extremes resulting in Earth moment of inertia changes owing to the tidal deformation and other coincidences with factors influencing the Earth's rotation as 8.45 years Moon perigee rotation and 18.63 years nodal variation present next proofs. The last confirmation follows from the earthquake repetitions in 19 years Metonic cycle. But claims that the plate movement is caused by the mantle convection or by inhomogenities in the mantle or even by the Earth's expansions are easily disprovable conjectures.

  5. Geophysical expression of a buried niobium and rare earth element deposit: the Elk Creek carbonatite, Nebraska, USA

    NASA Astrophysics Data System (ADS)

    Drenth, B.; Phillips, J. D.; Kass, A.; Krahenbuhl, R. A.

    2014-12-01

    The lower Paleozoic Elk Creek carbonatite is a 6-8 kilometer diameter intrusive complex buried under 200 meters of sedimentary rocks in southeastern Nebraska. It hosts the largest known niobium deposit in the U.S. and a rare earth element (REE) deposit. The carbonatite is composed of several lithologies, the relations of which are poorly understood. Niobium mineralization is most enriched within a magnetite beforsite unit, and REE oxides are concentrated in a barite beforsite unit. The carbonatite intrudes Proterozoic country rocks. A high-resolution airborne gravity gradient and magnetic survey was flown over the carbonatite in 2012. The carbonatite is associated with an annular vertical gravity gradient high with a subdued central low, and a central magnetic high surrounded by magnetic field values lower than those over the country rocks. Geophysical, borehole, and physical property data are combined for an interpretation of these signatures. The carbonatite is denser than the country rocks, explaining the gravity gradient high. Most carbonatite lithologies have weaker magnetic susceptibilities than those of the country rocks, explaining why the carbonatite produces a magnetic low at its margin. The primary source of the central magnetic high is interpreted to be mafic rocks that are strongly magnetized and are present in large volumes. Magnetite beforsite is very dense (mean density 3200 kg/m3) and strongly magnetized (median 0.073 SI magnetic susceptibility), producing a gravity gradient high and contributing to the aeromagnetic high. Barite beforsite has physical properties similar to most of the carbonatite volume, making it a poor geophysical target. Geophysical anomalies indicate the presence of dense and strongly magnetized rocks at depths below existing boreholes, either a large volume of magnetite beforsite or another unknown lithology. Studies are underway to investigate possible effects of alteration and magnetic remanence, and to better constrain the

  6. EarthScope: A distributed, multi-purpose geophysical observatory for the structure and dynamics of the North American continent

    NASA Astrophysics Data System (ADS)

    Jackson, Mike E.; Woodward, R.

    2010-05-01

    EarthScope, a broad-based geophysics program funded by the US National Science Foundation, takes a multidisciplinary approach to studying the structure and evolution of the North American continent and the physical processes controlling earthquakes and volcanoes. The integrated observing systems that make up the EarthScope facilities provide data streams that address fundamental questions at a variety of scales including the active nucleation zone of earthquakes, individual faults and volcanoes, the deformation along the plate boundary, and the structure of the continent and planet. EarthScope data are freely and openly available to maximize participation from the national and international scientific community and to provide ongoing educational outreach to students and the public. EarthScope facilities include the San Andreas Fault Observatory at Depth (SAFOD), the Plate Boundary Observatory (PBO), and the USArray. With leadership from the U.S. academic research community, consortium members, and through collaboration with other national and international organizations, IRIS operates, maintains, and manages the USArray facility and UNAVCO manages the PBO and SAFOD facilities. USArray consists of a portable array of 400 broadband seismometers that traverse North America and Alaska over a 15- year period; a pool of broadband, short-period, and active source seismometers available for deployment in areas where a denser observations are required; and seven permanent and 20 portable magnetotelluric (MT) instruments. SAFOD consists of a 3.1 km instrumented and core-sampled borehole that crosses the seismogenic zone of the San Andreas fault, designed to directly reveal the physical and chemical processes controlling earthquake generation. The PBO is a permanent network of continuous Global Positioning System (CGPS) stations, borehole tensor strainmeters, long baseline laser strainmeters, and a pool of campaign GPS units that provide deformation data for fundamental

  7. Geophysical interpretation of satellite laser ranging measurements of crustal movement in California

    NASA Astrophysics Data System (ADS)

    Cohen, Steven C.

    1985-12-01

    As determined by satellite laser ranging the rate of contraction of a 900 km baseline between sites located near Quincy in northern California and San Diego in southern California is about 61-65 mm/yr with a formal uncertainty of about 10 mm/yr (Christodoulidis et al., 1985). The measured changes in baseline length are a manifestation of the relative motion between the North America and Pacific tectonic plates. This long baseline result is compared to measurements made by more conventional means on shorter baselines. Additional information based on seismiscity, geology, and theoretical modelling is also analyzed. Deformation lying within a few tens of kilometers about the major faults in southern California accounts for most, but not all, of the observed motion. Further motion is attributable to a broader-scale deformation in southern California. Data suggesting crustal movements north of the Garlock fault, in and near the southern Sierra Nevada and local motion at an observatory are also critically reviewed. The best estimates of overall motion indicated by ground observations lie between 40 and 60 mm/yr. This lies within one or two standard deviations of that deduced from satellite ranging but the possibility of some unresolved deficit cannot be entirely dismissed. The long time scale RM2 plate tectonic model of Minster and Jordan (1978) predicts a contraction between 47 and 53 mm/yr depending on the extension rate of the Basin and Range. Thus the ground based observations, SLR results, and RM2 rates differ at about the 10 mm/yr level but are not inconsistent with one another within the data and model uncertainties.

  8. Geophysical interpretation of satellite laser ranging measurements of crustal movement in California

    NASA Astrophysics Data System (ADS)

    Cohen, S. C.

    1984-08-01

    As determined by satellite laser ranging the rate of contraction of a 900 kilometer baseline between sites located near Quincy in northern California and San Diego in southern California is about 61 to 65 mm/yr with a formal uncertainty of about 10 mm/yr. The measured changes in baseline length are a manifestation of the relative motion between the North America and Pacific tectonic plates. This long baseline result is compared to measurements made by more conventional means on shorter baselines. Additional information based on seismicity, geology, and theoretical modelling is also analyzed. Deformation lying within a few tens of kilometers about the major faults in southern California accounts for most, but not all of the observed motion. Further motion is attributable to a broader scale deformation in southern California. Data suggesting crustal movements north of the Garlock fault, in and near the southern Sierra Nevada and local motion at an observatory are also critically reviewed. The best estimates of overall motion indicated by ground observations lie between 40 and 60 mm/yr. This lies within one or two standard deviations of that deduced by satellite ranging but the possibility of some unresolved deficit cannot be dismissed. The long time scale RM2 plate tectonic model of Minster and Jordan predicts a contraction between 47 and 53 mm/yr depending on the extension rate of the Basin and Range. Thus the ground based observations, satellite laser ranging (SLR) results, and RM2 rates differ at about the 10 mm/yr level and are consistent with one another within the data and model uncertainties.

  9. Geophysical interpretation of satellite laser ranging measurements of crustal movement in California

    NASA Technical Reports Server (NTRS)

    Cohen, S. C.

    1984-01-01

    As determined by satellite laser ranging the rate of contraction of a 900 kilometer baseline between sites located near Quincy in northern California and San Diego in southern California is about 61 to 65 mm/yr with a formal uncertainty of about 10 mm/yr. The measured changes in baseline length are a manifestation of the relative motion between the North America and Pacific tectonic plates. This long baseline result is compared to measurements made by more conventional means on shorter baselines. Additional information based on seismicity, geology, and theoretical modelling is also analyzed. Deformation lying within a few tens of kilometers about the major faults in southern California accounts for most, but not all of the observed motion. Further motion is attributable to a broader scale deformation in southern California. Data suggesting crustal movements north of the Garlock fault, in and near the southern Sierra Nevada and local motion at an observatory are also critically reviewed. The best estimates of overall motion indicated by ground observations lie between 40 and 60 mm/yr. This lies within one or two standard deviations of that deduced by satellite ranging but the possibility of some unresolved deficit cannot be dismissed. The long time scale RM2 plate tectonic model of Minster and Jordan predicts a contraction between 47 and 53 mm/yr depending on the extension rate of the Basin and Range. Thus the ground based observations, satellite laser ranging (SLR) results, and RM2 rates differ at about the 10 mm/yr level and are consistent with one another within the data and model uncertainties.

  10. Geophysics education on the Internet: Course production and assessment of our MOOC, "Deep Earth Science"

    NASA Astrophysics Data System (ADS)

    Okuda, Y.; Tazawa, K.; Sugie, K.; Sakuraba, H.; Hideki, M.; Tagawa, S.; Cross, S. J.

    2016-12-01

    Recently, massive open online courses (MOOC or MOOCs) have gained wide-spread attention as a new educational platform delivered via the internet. Many leading institutions all over the world have provided many fascinating MOOC courses in various fields. Students enrolled in MOOCs study their interested topic in a course not only by watching video lectures, reading texts, and answering questions, but also by utilizing interactive online tools such as discussion boards, Q&A sessions and peer assessments. MOOC is also gaining popularity as a way to do outreach activity and diffuse research results. Tokyo Institute of Technology provided its 1st MOOC, "Introduction to Deep Earth Science Part1" on edX, which is one of the largest MOOC providers. This four-week-long course was designed for 1st year college students and with two learning goals in this course; 1) to introduce students to the fascinating knowledge of solid Earth, 2) to provide an opportunity to use scientific thinking as well as to show how interesting and exciting science can be. This course contained materials such as 1) structure of inside of the Earth 2) internal temperature of the earth and how it is estimated and 3) chemical compositions and dynamics inside the earth. After the end of the provision of Part1, this course was re-made as "Introduction to Deep Earth Science"(so to speak, Part2) on the basis of opinions obtained from students who have attended our course and student teaching assistants (TA) who have run and produced this course. In this presentation, we will explain our MOOC making model, which is a team based course creation effort between the course instructor, Tokyo Tech Online Education Development Office (OEDO) staff and TA students. Moreover, we will share details and feedback of Part1 received from some of the 5000 enrolled students from 150 counties and regions, and report the implementation of Part2 in the light of challenges resulted from Part1.

  11. Large-scale geophysical and geological-prospecting earth-crust investigation using high-power electromagnetic pulses

    NASA Astrophysics Data System (ADS)

    Velikhov, E. P.; Panchenko, V. P.

    2005-12-01

    The paper presents the concept and physical/technical prerequisites for the use of multi-megawatt electromagnetic pulses created, for instance, by autonomous MHD facilities of short-term operation (3--12 seconds), in fundamental and applied in-depth geophysical and geological research. Location of geological sites and research regions; circuits and parameters of emitting and detecting devices; unique pulse MHD facilities of 10--100 MWe capacity using solid (powder) fuel, created in Russia; conditions and methods of conducting large-scale experiments and trial methodical works, performed in the last 30 years by a cooperative group of Russian institute in various regions of Russia, Kyrghizia and Tajikistan, are described. Results of the following large-scale experiments and methodical works are presented: Oil and gas deposits' searching (Caspian depression, East Siberia); Study of electric conduction of sediments near and on the sea shelf (Kola peninsula); Electrical prospecting of ore deposits at depths of up to 10 km (Kola peninsula); Study of geo-electrical composition (section) of the earth-crust and upper mantle at the Ural (up to 40 km), and in the Baltic (up to 150 km); Forecasting of earthquakes using the effective electric resistance of earth-crust blocks up to 20 km deep (Tajikistan, Kirghizia); Seismic earth-crust "unloading", and changing the time-dependent distribution of the seismic activity under high-power electromagnetic impact; Impact on the ionosphere and spreading of ultra-low-frequency electromagnetic waves emitted by a high-power source. The possibilities and prospects of research dedicated to developing the technologies for electrical prospecting, sorting and outlining hydrocarbon deposits on the shelf, as well as to monitoring and studying the processes occurring in the earth-crust under artificial high-power electromagnetic impact in seismic regions, are discussed.

  12. Human vertical eye movement responses to earth horizontal pitch

    NASA Technical Reports Server (NTRS)

    Wall, C. 3rd; Petropoulos, A. E.

    1993-01-01

    The vertical eye movements in humans produced in response to head-over-heels constant velocity pitch rotation about a horizontal axis resemble those from other species. At 60 degrees/s these are persistent and tend to have non-reversing slow components that are compensatory to the direction of rotation. In most, but not all subjects, the slow component velocity was well characterized by a rapid build-up followed by an exponential decay to a non-zero baseline. Super-imposed was a cyclic or modulation component whose frequency corresponded to the time for one revolution and whose maximum amplitude occurred during a specific head orientation. All response components (exponential decay, baseline and modulation) were larger during pitch backward compared to pitch forward runs. Decay time constants were shorter during the backward runs, thus, unlike left to right yaw axis rotation, pitch responses display significant asymmetries between paired forward and backward runs.

  13. Human vertical eye movement responses to earth horizontal pitch

    NASA Technical Reports Server (NTRS)

    Wall, C. 3rd; Petropoulos, A. E.

    1993-01-01

    The vertical eye movements in humans produced in response to head-over-heels constant velocity pitch rotation about a horizontal axis resemble those from other species. At 60 degrees/s these are persistent and tend to have non-reversing slow components that are compensatory to the direction of rotation. In most, but not all subjects, the slow component velocity was well characterized by a rapid build-up followed by an exponential decay to a non-zero baseline. Super-imposed was a cyclic or modulation component whose frequency corresponded to the time for one revolution and whose maximum amplitude occurred during a specific head orientation. All response components (exponential decay, baseline and modulation) were larger during pitch backward compared to pitch forward runs. Decay time constants were shorter during the backward runs, thus, unlike left to right yaw axis rotation, pitch responses display significant asymmetries between paired forward and backward runs.

  14. Glacier Geophysics: Dynamic response of glaciers to changing climate may shed light on processes in the earth's interior.

    PubMed

    Kamb, B

    1964-10-16

    From physical measurements on glaciers and experimental studies of ice properties a framework of concept and theory is being built which bids fair to place glaciers among the more quantitatively understandable phenomena in the earth sciences. Measurements of flow velocity, deformation and stress, ice thickness and channel configuration, temperature, internal structure of theice, mass and energy balance, and response to meteorological variables all contribute to this understanding, as do still other measurements hardly discussed here, such as electrical properties, radioactive age measurements, and detailed studies of chemical and isotopic composition. The obvious goals of this work-the interpretation of past and present glacier fluctuations in terms of changes in world climate, and the prediction of glacier behavior-remain elusive, even though a good conceptual groundwork has been laid for dealing with the more tractable aspects of these problems. Intriguing recent discoveries have been made about such matters as the way in which glaciers react dynamically to changing conditions, the inter-relations between thermal regime and ice motion, the structural mechanisms of glacier flow, and the changes produced in ice by flow. One can recognize in these developments the possibility that concepts derived from the study of glacier flow may be applicable to phenomena of solid deformation deep in the earth. In this way glacier geophysics may have a useful impact beyond the study of glaciers themselves.

  15. Controlling reaching movements during self-motion: body-fixed versus Earth-fixed targets.

    PubMed

    Guillaud, Etienne; Simoneau, Martin; Gauthier, Gabriel; Blouin, Jean

    2006-10-01

    The control of goal-directed arm movements performed during whole-body displacements is far from being understood. Recent studies suggested that the compensatory arm movements that allow individuals to preserve hand-in-space trajectory during unexpected body motion are controlled by sensorimotor, automatic- like processes. We tested this hypothesis comparing both the accuracy of movements directed towards body-fixed or Earth-fixed target during body rotations and the amount of interference of the reaching tasks on a concurrent cognitive task. Participants reached for a memorized 55 cm distant straight-ahead target in darkness which was about 20 cm lower than the initial finger position. The target was either body-fixed or Earth-fixed. At reaching onset, participants could be rotated in yaw. The concurrent task consisted of a verbal reaction time (RT) to an auditory stimulus. RTs increased when participants reached for the target while they were rotated. However, this increase was not significantly different for body-fixed and Earth-fixed targets. Reaching accuracy was greater for body-fixed than for Earth-fixed targets. A control experiment suggested that the errors in the Earth-fixed target condition arose from a difficulty in the organization of movements which necessitate both the production of active forces at the shoulder joint (to compensate for body rotation) and a concomitant decrease of muscular activation to lower the arm during reaching movements. These findings suggest that reaching for Earth-fixed or body-fixed targets during body rotation cannot be considered as being purely automatic tasks.

  16. Rare earth mineral potential in the southeastern U.S. Coastal Plain from integrated geophysical, geochemical, and geological approaches

    USGS Publications Warehouse

    Shah, Anjana K.; Bern, Carleton; Van Gosen, Bradley S.; Daniels, David L.; Benzel, William M.; Budahn, James R.; Ellefsen, Karl J.; Karst, Adam; Davis, Richard

    2017-01-01

    We combined geophysical, geochemical, mineralogical, and geological data to evaluate the regional presence of rare earth element (REE)−bearing minerals in heavy mineral sand deposits of the southeastern U.S. Coastal Plain. We also analyzed regional differences in these data to determine probable sedimentary provenance. Analyses of heavy mineral separates covering the region show strong correlations between thorium, monazite, and xenotime, suggesting that radiometric equivalent thorium (eTh) can be used as a geophysical proxy for those REE-bearing minerals. Airborne radiometric data collected during the National Uranium Resource Evaluation (NURE) program cover the southeastern United States with line spacing varying from ∼2 to 10 km. These data show eTh highs over Cretaceous and Tertiary Coastal Plain sediments from the Cape Fear arch in North Carolina to eastern Alabama; these highs decrease with distance from the Piedmont. Quaternary sediments along the modern coasts show weaker eTh anomalies, except near coast-parallel ridges from South Carolina to northern Florida. Prominent eTh anomalies are also observed over large riverbeds and their floodplains, even north of the Cape Fear arch where surrounding areas are relatively low. These variations were verified using ground geophysical measurements and sample analyses, indicating that radiometric methods are a useful exploration tool at varying scales. Further analyses of heavy mineral separates showed regional differences, not only in concentrations of monazite, but also of rutile and staurolite, and in magnetic susceptibility. The combined properties suggest the presence of subregions where heavy mineral sediments are primarily sourced from high-grade metamorphic, low-grade metamorphic, or igneous terrains, or where they represent a mixing of these sources. Comparisons between interpreted sources of heavy mineral sands near the Fall Line and igneous and metamorphic Piedmont and Blue Ridge units showed a strong

  17. Infrasound as a Geophysical Probe Using Earth as a Venus Analog

    NASA Astrophysics Data System (ADS)

    Komjathy, A.; Cutts, J. A.; Pauken, M.; Kedar, S.; Smrekar, S. E.; Hall, J. R.

    2016-12-01

    JPL is in a process of developing an instrument to measure seismic activity on Venus by detecting infrasonic waves in the atmosphere. The overall objective of this research is to demonstrate the feasibility of using sensitive barometers to detect infrasonic signals from seismic and explosive activity on Venus from a balloon platform. Because of Venus' dense atmosphere, seismic signatures from even small quakes (magnitude 3) are effectively coupled into the atmosphere. The seismic signals are known to couple about 60 times more efficiently into the atmosphere on Venus than on Earth. It was found that almost no attenuation below 80 km on Venus for frequency less than 1Hz. Whereas wind noise is a major source of background noise for terrestrial infrasonic arrays, it is expected that a balloon platform, which drifts with winds will be capable of very sensitive measurements with low noise. In our research we will demonstrate and apply techniques for discriminating upward propagating waves from a seismic event by making measurements with two or more infrasonic sensors using very sensitive barometers on a tether deployed from the balloon in a series of earth-based tests. We will first demonstrate and validate the technique using an artificial infrasound source in a deployment from a hot air balloon on Earth and then extend it with longer duration flights in the troposphere and stratosphere. We will report results on the first flight experiment that will focus on using the barometer instruments on a tethered helium-filled balloon. The balloon flight will be conducted in the vicinity of a known seismic source generated by a seismic hammer. Earlier tests conducted by Sandia National Laboratory demonstrated that this is a highly reproducible source of seismic and acoustic energy using infrasound sensors. The results of the experiments are intended to validate the two-barometer signal processing approach using a well-characterized point signal source.

  18. Infrasound as a Geophysical Probe Using Earth as a Venus Analog

    NASA Astrophysics Data System (ADS)

    Komjathy, Attila; Cutts, James; Pauken, Michael; Kedar, Sharon; Smrekar, Suzanne

    2016-10-01

    JPL is in a process of developing an instrument to measure seismic activity on Venus by detecting infrasonic waves in the atmosphere. The overall objective of this research is to demonstrate the feasibility of using sensitive barometers to detect infrasonic signals from seismic and explosive activity on Venus from a balloon platform. Because of Venus' dense atmosphere, seismic signatures from even small quakes (magnitude ~3) are effectively coupled into the atmosphere. The seismic signals are known to couple about 60 times more efficiently into the atmosphere on Venus than on Earth. It was found that almost no attenuation below 80 km on Venus for frequency less than 1Hz. Whereas wind noise is a major source of background noise for terrestrial infrasonic arrays, it is expected that a balloon platform, which drifts with winds will be capable of very sensitive measurements with low noise.In our research we will demonstrate and apply techniques for discriminating upward propagating waves from a seismic event by making measurements with two or more infrasonic sensors using very sensitive barometers on a tether deployed from the balloon in a series of earth-based tests. We will first demonstrate and validate the technique using an artificial infrasound source in a deployment from a hot air balloon on Earth and then extend it with longer duration flights in the troposphere and stratosphere.We will report results on the first flight experiment that will focus on using the barometer instruments on a tethered helium-filled balloon. The balloon flight will be conducted in the vicinity of a known seismic source generated by a seismic hammer. Earlier tests conducted by Sandia National Laboratory demonstrated that this is a highly reproducible source of seismic and acoustic energy using infrasound sensors. The results of the experiments are intended to validate the two-barometer signal processing approach using a well-characterized point signal source.

  19. Tracing sediment movement on semi-arid watershed using Rare Earth Elements 1988

    USDA-ARS?s Scientific Manuscript database

    A multi-tracer method employing rare earth elements (REE) was used to determine sediment yield and to track sediment movement in a small semiarid watershed. A 0.33 ha watershed near Tombstone, AZ was divided into five morphological units, each tagged with one of five REE oxides. Relative contributi...

  20. Geophysical Framework of a Rare Earth Element Enriched Terrane, Mountain Pass, California

    NASA Astrophysics Data System (ADS)

    Denton, K. M.; Ponce, D. A.; Peacock, J.; Miller, D. M.; Miller, J. S.

    2016-12-01

    Carbonatite ore deposits continue to be the primary source for rare earth elements (REEs), however large viable REE ore deposits are uncommon. The Mountain Pass carbonatite deposit, located in the eastern Mojave Desert of California, is the largest economic deposit of light REEs in North America. A 1.417 Ga ultrapotassic suite (shonkinite, syenite, and granite) and a 1.375 Ga barite-bastnasite-rich carbonatite (sovite) ore deposit comprise the enclave of REE-enriched outcrops and dikes that occupy a narrow ( 3 km) zone of 1.7 Ga gneiss extending at least 10-km to the southeast from southern Clark Mountain. Modeling of gravity, magnetic, and magnetotelluric (MT) data reveals subsurface features that form the structural framework of the REE terrane. The carbonatite and ultrapotassic mafic suite is associated with a local gravity high that is superimposed on a 4 km-wide gravity terrace, likely related to less dense granitic gneiss basement. Although physical property data indicate that the intrusive suite and carbonatite are essentially and nonmagnetic, aeromagnetic data indicate that these rocks occur along the eastern edge of a prominent north-northwest trending aeromagnetic high. This relationship suggests that they may have been preferentially emplaced along a zone of weakness or fault. The source of the magnetic high is 2-3 km below the surface and coincides with a relatively electrically conductive (3 orders of magnitude higher than surrounding rock) feature. MT data indicate that the western edge of the magnetic feature could be connected to a deeper ( 8 km) conductive feature related to possible intrusions and/or hydrothermal systems. The lack of a magnetic signature of the REE terrane can be explained by alteration of magnetite, given that the terrane lies within a broader alteration zone and observed magnetic low. If so, such an alteration event, capable of remobilizing rare earth elements, likely occurred during or after emplacement of the intrusive suite

  1. Observed changes in the Earth's dynamic oblateness from GRACE data and geophysical models.

    PubMed

    Sun, Y; Ditmar, P; Riva, R

    A new methodology is proposed to estimate changes in the Earth's dynamic oblateness ([Formula: see text] or equivalently, [Formula: see text]) on a monthly basis. The algorithm uses monthly Gravity Recovery and Climate Experiment (GRACE) gravity solutions, an ocean bottom pressure model and a glacial isostatic adjustment (GIA) model. The resulting time series agree remarkably well with a solution based on satellite laser ranging (SLR) data. Seasonal variations of the obtained time series show little sensitivity to the choice of GRACE solutions. Reducing signal leakage in coastal areas when dealing with GRACE data and accounting for self-attraction and loading effects when dealing with water redistribution in the ocean is crucial in achieving close agreement with the SLR-based solution in terms of de-trended solutions. The obtained trend estimates, on the other hand, may be less accurate due to their dependence on the GIA models, which still carry large uncertainties.

  2. The importance of a multidisciplinary approach for solid earth geophysics in Seafloor Observatories data analysis

    NASA Astrophysics Data System (ADS)

    Embriaco, Davide; De Caro, Mariagrazia; De Santis, Angelo; Etiope, Giuseppe; Frugoni, Francesco; Giovanetti, Gabriele; Lo Bue, Nadia; Marinaro, Giuditta; Monna, Stephen; Montuori, Caterina; Sgroi, Tiziana; Beranzoli, Laura; Favali, Paolo

    2016-04-01

    Continuous time-series in deep ocean waters are the basis for an original approach in ocean exploration. The observation of phenomena variability over time is key to understanding many Earth processes, among which: hydrothermal systems, active tectonics, and ecosystem life cycles. Geo-hazards at sea have often been studied with a single-parameter approach on a short time-scale, but it is now becoming clear that to understand these phenomena and, specifically, to identify precursors to very energetic events, such as mega-earthquakes, tsunamis and volcanic eruptions, continuous long-term multiparameter monitoring is strongly needed. In fact, given a signal of interest, by using several sensors recording simultaneously it is possible to identify the contribution of different sources to this signal, and to be less prone to false associations. In Europe, large cabled systems with marine sensors are being developed for near real-time and real-time long-term monitoring of ocean processes within the EMSO (European Multidisciplinary Seafloor and water column Observatory www.emso-eu.org) Research Infrastructure. Obtaining good quality long-term multiparameter data from sensors on-board seafloor observatories, which are the base of a multidisciplinary approach, is a challenging task. We describe the main steps we have taken to retrieve good quality multiparametric data acquired by GEOSTAR class seafloor observatories, both standalone and cabled, deployed at various sites offshore European coast during the last decade. Starting from this data we show the application of a multidisciplinary approach with some examples coming from experiments in EMSO sites.

  3. Spatial coding of eye movements relative to perceived earth and head orientations during static roll tilt

    NASA Technical Reports Server (NTRS)

    Wood, S. J.; Paloski, W. H.; Reschke, M. F.

    1998-01-01

    This purpose of this study was to examine the spatial coding of eye movements during static roll tilt (up to +/-45 degrees) relative to perceived earth and head orientations. Binocular videographic recordings obtained in darkness from eight subjects allowed us to quantify the mean deviations in gaze trajectories along both horizontal and vertical coordinates relative to the true earth and head orientations. We found that both variability and curvature of gaze trajectories increased with roll tilt. The trajectories of eye movements made along the perceived earth-horizontal (PEH) were more accurate than movements along the perceived head-horizontal (PHH). The trajectories of both PEH and PHH saccades tended to deviate in the same direction as the head tilt. The deviations in gaze trajectories along the perceived earth-vertical (PEV) and perceived head-vertical (PHV) were both similar to the PHH orientation, except that saccades along the PEV deviated in the opposite direction relative to the head tilt. The magnitude of deviations along the PEV, PHH, and PHV corresponded to perceptual overestimations of roll tilt obtained from verbal reports. Both PEV gaze trajectories and perceptual estimates of tilt orientation were different following clockwise rather than counterclockwise tilt rotation; however, the PEH gaze trajectories were less affected by the direction of tilt rotation. Our results suggest that errors in gaze trajectories along PEV and perceived head orientations increase during roll tilt in a similar way to perceptual errors of tilt orientation. Although PEH and PEV gaze trajectories became nonorthogonal during roll tilt, we conclude that the spatial coding of eye movements during roll tilt is overall more accurate for the perceived earth reference frame than for the perceived head reference frame.

  4. Spatial coding of eye movements relative to perceived earth and head orientations during static roll tilt

    NASA Technical Reports Server (NTRS)

    Wood, S. J.; Paloski, W. H.; Reschke, M. F.

    1998-01-01

    This purpose of this study was to examine the spatial coding of eye movements during static roll tilt (up to +/-45 degrees) relative to perceived earth and head orientations. Binocular videographic recordings obtained in darkness from eight subjects allowed us to quantify the mean deviations in gaze trajectories along both horizontal and vertical coordinates relative to the true earth and head orientations. We found that both variability and curvature of gaze trajectories increased with roll tilt. The trajectories of eye movements made along the perceived earth-horizontal (PEH) were more accurate than movements along the perceived head-horizontal (PHH). The trajectories of both PEH and PHH saccades tended to deviate in the same direction as the head tilt. The deviations in gaze trajectories along the perceived earth-vertical (PEV) and perceived head-vertical (PHV) were both similar to the PHH orientation, except that saccades along the PEV deviated in the opposite direction relative to the head tilt. The magnitude of deviations along the PEV, PHH, and PHV corresponded to perceptual overestimations of roll tilt obtained from verbal reports. Both PEV gaze trajectories and perceptual estimates of tilt orientation were different following clockwise rather than counterclockwise tilt rotation; however, the PEH gaze trajectories were less affected by the direction of tilt rotation. Our results suggest that errors in gaze trajectories along PEV and perceived head orientations increase during roll tilt in a similar way to perceptual errors of tilt orientation. Although PEH and PEV gaze trajectories became nonorthogonal during roll tilt, we conclude that the spatial coding of eye movements during roll tilt is overall more accurate for the perceived earth reference frame than for the perceived head reference frame.

  5. Spatial coding of eye movements relative to perceived earth and head orientations during static roll tilt.

    PubMed

    Wood, S J; Paloski, W H; Reschke, M F

    1998-07-01

    This purpose of this study was to examine the spatial coding of eye movements during static roll tilt (up to +/-45 degrees) relative to perceived earth and head orientations. Binocular videographic recordings obtained in darkness from eight subjects allowed us to quantify the mean deviations in gaze trajectories along both horizontal and vertical coordinates relative to the true earth and head orientations. We found that both variability and curvature of gaze trajectories increased with roll tilt. The trajectories of eye movements made along the perceived earth-horizontal (PEH) were more accurate than movements along the perceived head-horizontal (PHH). The trajectories of both PEH and PHH saccades tended to deviate in the same direction as the head tilt. The deviations in gaze trajectories along the perceived earth-vertical (PEV) and perceived head-vertical (PHV) were both similar to the PHH orientation, except that saccades along the PEV deviated in the opposite direction relative to the head tilt. The magnitude of deviations along the PEV, PHH, and PHV corresponded to perceptual overestimations of roll tilt obtained from verbal reports. Both PEV gaze trajectories and perceptual estimates of tilt orientation were different following clockwise rather than counterclockwise tilt rotation; however, the PEH gaze trajectories were less affected by the direction of tilt rotation. Our results suggest that errors in gaze trajectories along PEV and perceived head orientations increase during roll tilt in a similar way to perceptual errors of tilt orientation. Although PEH and PEV gaze trajectories became nonorthogonal during roll tilt, we conclude that the spatial coding of eye movements during roll tilt is overall more accurate for the perceived earth reference frame than for the perceived head reference frame.

  6. Multi-Objective Geophysical Inversion for Earth Structure and Earthquake Parameters

    NASA Astrophysics Data System (ADS)

    Chai, Chengping

    For Earth structure imaging, increasing station coverage provide large quantities of seismic observations. These observations are not free of noise and some suffered from scattering noise. We developed techniques to reduce scattering noise by incorporating observations from adjacent stations and to extract signals from deeper structure using better-determined shallow prior information. In the second chapter, we use P wave receiver functions from the western U.S. and adjacent regions to construct a receiver function wavefield interpolation scheme that helps to equalize the lateral sampling of the receiver functions and the surface wave dispersion and to greatly simplify the receiver functions. Spatial interpolation and smoothing suppress poorly sampled and difficult to interpret back azimuthal variations and allow the extraction of the first-order features in the receiver function wavefield, including observations from several ray parameter ranges. We combine the interpolated receiver functions with Rayleigh wave dispersion estimates and surface gravity observations to estimate the 3-D shear wave speed beneath the region. Speed variations in the 3-D model correlate strongly with expected geologic variations and illuminate broad-scale features of the western U.S. crust and upper mantle. The model is smooth, self-consistent, and demonstrates the compatibility of the interpolated receiver functions and dispersion observations. In the third chapter, we simultaneously invert smoothed P-wave receiver functions, Rayleigh wave phase and group velocity measurements, and Bouguer gravity observations for the 3D shear wave speed beneath the eastern U.S. and the northern Mississippi Embayment regions. Using period-coverage-broadened (3-250 s) surface-wave observations and spatially smoothed receiver functions, our velocity models are robust, reliable and rich in detail. Our shear-wave velocity models fit all three types of observations well. The resulting velocity model in for

  7. Environmental Geophysics

    EPA Pesticide Factsheets

    The Environmental Geophysics website features geophysical methods, terms and references; forward and inverse geophysical models for download; and a decision support tool to guide geophysical method selection for a variety of environmental applications.

  8. Investigation of Karst Cavities and Earth Subsidence with Combined Application of Boring and Geophysics in the Progress of High-Speed Railway Routes

    NASA Astrophysics Data System (ADS)

    Lehmann, Bodo; Pöttler, Rudolf; Radinger, Alexander; Kühne, Manfred

    In Germany there are a lot of new high-speed railways in planning or under construction. One of these is the new Nuremberg - Ingolstadt railway line and the updated line from Ingolstadt to Munich. These two lines will form part of a high-speed trans-European railway link from Scandinavia via Berlin to Munich and Verona. The 78 km railway line construction project has been divided into three contract sections: Contract Section North, mainly characterised by pure earth and bridge works; Contract Section Centre, with the emphasis mainly on tunnel construction; and Contract Section South, combining earthworks and tunnelling. Extensive geophysical investigations combined with borings are carried out in critical areas between Nuremberg and Ingolstadt. The target of this geological exploration phase is mainly the detection of karst pits and earth subsidences (dolines). In this area these geological objects are an important aspect for the stability and permanent serviceability of the high-speed railway routes. The exploration concept on the open stretch consists of combined geological enquiry, geotechnical work, geophysical investigations and borings, which are positioned at the found anomalies of geophysics. The survey leads to a common interpretation of all information and results. After several test campaigns the combination of at least two geophysical methods yields to the best results. Dependent on the thickness of the overburden layer seismics, micro-gravity and/or georadar are applied from the surface. Additionally tomographic methods are used between boreholes for special topics. Important for the success of the investigation in difficult geological areas are the excellent co-operation between all scientists, engineers and technicians (geologists, geotechnicians, geophysicists, driller, consultants, etc.).

  9. Using the Earth as a guide to martian mass movement processes: From form to process

    NASA Astrophysics Data System (ADS)

    Lanza, N.; Newsom, H. E.; Osterloo, M. M.; Okubo, C. H.

    2011-12-01

    The discovery of gully features on Mars has led to renewed interest in hillslope processes on that planet, in particular mass movement and the morphologies that it produces. Mass movement is a collection of gravity-driven processes that act to move materials down a hillslope. Here, we examine how mass movements on hillslopes may be expected to differ on Earth and Mars as the result of gravity differences between these planets. Downslope movement of unconsolidated materials is generally controlled by the bulk shear strength of these materials. Although the relationship between gravity and shear strength is largely dependent on variables that are independent of gravity, the lower gravity on Mars is expected to produce some systematic changes in mass movement behaviors that may in turn create morphological features that are observably different from their terrestrial counterparts. After scaling for gravity and modifying empirically derived relationships, we may expect the following differences on martian hillslopes when compared to their terrestrial counterparts: ==On Mars, hillslopes may have steeper angles of repose in fine grained (< ~2 mm) materials, even when dry. No change in angle of repose is expected for larger particles; ==An increase in soil moisture content (e.g., excess pore pressure) is expected to weaken unconsolidated slope materials more on Mars for a particular regolith type, which in turn may produce --An increase in creep rates for a given pore pressure, and --An increase in effectiveness of frost heave to transport materials downslope; ==Processes triggered by saturation may occur at lower pore pressures on Mars; --A smaller amount of fluid is needed to achieve failure; ==Shorter runout lengths are expected for rapid mass movements; ==On Mars, overland flow will exert a proportionally lower shear stress on slope materials; --In cohesive materials, the same volume of water will detach sediments of smaller sizes. On Earth, mass movement processes

  10. Resources for Computational Geophysics Courses

    NASA Astrophysics Data System (ADS)

    Keers, Henk; Rondenay, Stéphane; Harlap, Yaël.; Nordmo, Ivar

    2014-09-01

    An important skill that students in solid Earth physics need to acquire is the ability to write computer programs that can be used for the processing, analysis, and modeling of geophysical data and phenomena. Therefore, this skill (which we call "computational geophysics") is a core part of any undergraduate geophysics curriculum. In this Forum, we share our personal experience in teaching such a course.

  11. [Fractality, "coast line of the universe", movement of the earth and "macroscopic fluctuations"].

    PubMed

    Shnol', S E

    2013-01-01

    The evolution of views on the nature of "macroscopic fluctuations" phenomenon, discovered about sixty years ago as an "anomalous scattering of results" of actomyosin enzyme activity measurement, is traced in the paper. Ever since the general character of this phenomenon was stated because it was found in measurements of processes of different nature and caused by movement of the Earth in heterogeneous and anisotropic space-time. The paper is dedicated to the memory of L.A. Blumenfeld: a many-decade discussion with him favoured these investigations.

  12. WEST COAST REGIONAL CARBON SEQUESTRATION PARTNERSHIP - REPORT ON GEOPHYSICAL TECHNIQUES FOR MONITORING CO2 MOVEMENT DURING SEQUESTRATION

    SciTech Connect

    Gasperikova, Erika; Gasperikova, Erika; Hoversten, G. Michael

    2005-10-01

    The relative merits of the seismic, gravity, and electromagnetic (EM) geophysical techniques are examined as monitoring tools for geologic sequestration of CO{sub 2}. This work does not represent an exhaustive study, but rather demonstrates the capabilities of a number of geophysical techniques on two synthetic modeling scenarios. The first scenario represents combined CO{sub 2} enhance oil recovery (EOR) and sequestration in a producing oil field, the Schrader Bluff field on the north slope of Alaska, USA. EOR/sequestration projects in general and Schrader Bluff in particular represent relatively thin injection intervals with multiple fluid components (oil, hydrocarbon gas, brine, and CO{sub 2}). This model represents the most difficult end member of a complex spectrum of possible sequestration scenarios. The time-lapse performance of seismic, gravity, and EM techniques are considered for the Schrader Bluff model. The second scenario is a gas field that in general resembles conditions of Rio Vista reservoir in the Sacramento Basin of California. Surface gravity, and seismic measurements are considered for this model.

  13. Crisp clustering of airborne geophysical data from the Alto Ligonha pegmatite field, northeastern Mozambique, to predict zones of increased rare earth element potential

    NASA Astrophysics Data System (ADS)

    Eberle, Detlef G.; Daudi, Elias X. F.; Muiuane, Elônio A.; Nyabeze, Peter; Pontavida, Alfredo M.

    2012-01-01

    The National Geology Directorate of Mozambique (DNG) and Maputo-based Eduardo-Mondlane University (UEM) entered a joint venture with the South African Council for Geoscience (CGS) to conduct a case study over the meso-Proterozoic Alto Ligonha pegmatite field in the Zambézia Province of northeastern Mozambique to support the local exploration and mining sectors. Rare-metal minerals, i.e. tantalum and niobium, as well as rare-earth minerals have been mined in the Alto Ligonha pegmatite field since decades, but due to the civil war (1977-1992) production nearly ceased. The Government now strives to promote mining in the region as contribution to poverty alleviation. This study was undertaken to facilitate the extraction of geological information from the high resolution airborne magnetic and radiometric data sets recently acquired through a World Bank funded survey and mapping project. The aim was to generate a value-added map from the airborne geophysical data that is easier to read and use by the exploration and mining industries than mere airborne geophysical grid data or maps. As a first step towards clustering, thorium (Th) and potassium (K) concentrations were determined from the airborne geophysical data as well as apparent magnetic susceptibility and first vertical magnetic gradient data. These four datasets were projected onto a 100 m spaced regular grid to assemble 850,000 four-element (multivariate) sample vectors over the study area. Classification of the sample vectors using crisp clustering based upon the Euclidian distance between sample and class centre provided a (pseudo-) geology map or value-added map, respectively, displaying the spatial distribution of six different classes in the study area. To learn the quality of sample allocation, the degree of membership of each sample vector was determined using a-posterior discriminant analysis. Geophysical ground truth control was essential to allocate geology/geophysical attributes to the six classes

  14. Studies on different geophysical and extra-terrestrial events within the Earth-ionosphere cavity in terms of ULF/ELF/VLF radio waves

    NASA Astrophysics Data System (ADS)

    Sanfui, Minu; Haldar, D. K.; Biswas, Debasish

    2016-10-01

    The space between the two spherical conducting shells, Earth surface and the lower boundary of the ionosphere, behaves as a spherical cavity in which some electromagnetic signals can propagate a long distance and is called Earth-ionosphere waveguide. Through this waveguide ultra low frequency (ULF), extremely low frequency (ELF) and very low frequency (VLF) signals can propagate efficiently with low attenuation. Resonances which occur for ELF waves due to round-the-world propagation interfering with 2n π phase difference are called Schumann resonances. Lightnings are the main sources of energy continuously producing these electromagnetic radiations from the troposphere. Some fixed frequency signals are also transmitted through the waveguide from different stations for navigation purposes. The intensity and phase of these signals at a particular position depend on the waveguide characteristics which are highly influenced by different natural events. Thus the signatures of different geophysical and extra-terrestrial events may be investigated by studying these signals through proper monitoring of the time series data using suitable techniques. In this article, we provide a review on ULF, ELF and VLF signals within the waveguide in terms of different geophysical and extra-terrestrial events like lightning, earthquakes, Leonid meteor shower, solar flares, solar eclipse, geomagnetic storms, and TLEs etc.

  15. Integration of geotechnical and geophysical techniques for the characterization of a small earth-filled canal dyke and the localization of water leakage

    NASA Astrophysics Data System (ADS)

    Bièvre, Grégory; Lacroix, Pascal; Oxarango, Laurent; Goutaland, David; Monnot, Guy; Fargier, Yannick

    2017-04-01

    This paper investigates the combined use of extensive geotechnical, hydrogeological and geophysical techniques to assess a small earth dyke with a permanent hydraulic head, namely a canal embankment. The experimental site was chosen because of known issues regarding internal erosion and piping phenomena. Two leakages were visually located following the emptying of the canal prior to remediation works. The results showed a good agreement between the geophysical imaging techniques (Electrical Resistivity Tomography, P- and SH-waves Tomography) and the geotechnical data to detect the depth to the bedrock and its lateral variations. It appeared that surface waves might not be fully adapted for dyke investigation because of the particular geometry of the studied dyke, non-respectful of the 1D assumption, and which induced depth and velocity discrepancies retrieved from Rayleigh and Love waves inversion. The use of these classical prospecting techniques however did not allow to directly locate the two leakages within the studied earth dyke. The analysis of ambient vibration time series with a modified beam-forming algorithm allowed to localize the most energetic water flow prior to remediation works. It was not possible to detect the leakage after remediation works, suggesting that they efficiently contributed to significantly reduce the water flow. The second leakage was not detected probably because of a non-turbulent water flow, generating few energetic vibrations.

  16. Time-Variable Geophysical Background Models for High-Frequency Non-Tidal Variability in the Earth's Gravity Field, its Surface Deformation, and its Rotation provided by GFZ

    NASA Astrophysics Data System (ADS)

    Dobslaw, Henryk; Dill, Robert; Bergmann-Wolf, Inga; Poropat, Lea; Thomas, Maik

    2016-04-01

    Mass variability in atmosphere, oceans, and the terrestrially stored water is reflected in time variations of the Earth's gravity field, its surface deformations, and its rotation that are reliably picked up by geodetic networks and satellite missions since many years. For studies attempting to unveil signatures of solid Earth processes from such observations, its is highly important to remove signals caused by geophysical fluids on or above the surface as accurately as possible. At this poster, we are going to give a summary about the current status of the time-variable geophysical background models suitable for geodetic purposes that are currently processed at GFZ Potsdam. This will include the latest versions of the GRACE AOD1B background model; effective angular momentum functions for atmosphere, oceans, and the continental hydrosphere; as well as surface deformations due to tidal and non-tidal mass loads on the continents and the ocean floor. Latest news and all access details to the datasets are available at http://www.gfz-potsdam.de/en/section/earthsystemmodelling/services.

  17. Environmental and Engineering Geophysics

    NASA Astrophysics Data System (ADS)

    Sharma, Prem V.

    1997-12-01

    Geophysical imaging methods provide solutions to a wide variety of environmental and engineering problems: protection of soil and groundwater from contamination; disposal of chemical and nuclear waste; geotechnical site testing; landslide and ground subsidence hazard detection; location of archaeological artifacts. This book comprehensively describes the theory, data acquisition and interpretation of all of the principal techniques of geophysical surveying: gravity, magnetic, seismic, self-potential, resistivity, induced polarization, electromagnetic, ground-probing radar, radioactivity, geothermal, and geophysical borehole logging. Each chapter is supported by a large number of richly illustrated case histories. This book will prove to be a valuable textbook for senior undergraduates and postgraduates in environmental and applied geophysics, a supplementary course book for students of geology, engineering geophysics, civil and mining engineering, and a reference work for professional earth scientists, engineers and town planners.

  18. Basic exploration geophysics

    SciTech Connect

    Robinson, E.S.

    1988-01-01

    An introduction to geophysical methods used to explore for natural resources and to survey earth's geology is presented in this volume. It is suitable for second-and third-year undergraduate students majoring in geology or engineering and for professional engineering and for professional engineers and earth scientists without formal instruction in geophysics. The author assumes the reader is familiar with geometry, algebra, and trigonometry. Geophysical exploration includes seismic refraction and reflection surveying, electrical resistivity and electromagnetic field surveying, and geophysical well logging. Surveying operations are described in step-by-step procedures and are illustrated by practical examples. Computer-based methods of processing and interpreting data as well as geographical methods are introduced.

  19. [The reasons for the «space» of gerontology: the impact of the movements of the Earth and Moon on the performance of the human environment].

    PubMed

    Shapovalov, S N

    2016-01-01

    For future gerontological research specific interest are the research results obtained at the junction of Geophysics, astronomy, and biology, and existing links pointing to indicators of living objects with cosmophysical factors. The paper presents data on basic astronomical factors, potentially on a regular basis may cause gravitational effects on the biosphere as a living environment. Among these factors are movement of the Earth and Moon described is known in astronomy equations: the equation of the equinoxes, equation of time, as well as major perturbations from the Sun (evection, variation and annual inequality) inferred from the theory of lunar motion. Based on the amount of major perturbations from the Sun, the so-called λD-functions that are carried out to study the relationship between fluctuations of the so-called «computer time», the energy of solar radiation in the range of 605-607 nm, and the concentration of hemoglobin and red blood cells with major perturbations from the Sun. The resulting conclusion about the universal nature of the impact of the movements of the Moon and the Earth on the biosphere. The tables for the period from 01.01.2015 to 31.12.2016, with the calculated values λD functions that are potentially important for analyzing their association with temporal changes of various indicators of the body. The regularities obtained in the comparison of changes in various biomarkers with the course of values λD functions from tables, can be predictive in the study of the functioning of humans and the biosphere for astronomical periods. The research was carried out in Antarctica, where excluded the influence of artificial electromagnetic fields, st. Vostok (1998-1999) and st. Novolazarevskaya (2003-2004).

  20. International Symposium on Airborne Geophysics

    NASA Astrophysics Data System (ADS)

    Mogi, Toru; Ito, Hisatoshi; Kaieda, Hideshi; Kusunoki, Kenichiro; Saltus, Richard W.; Fitterman, David V.; Okuma, Shigeo; Nakatsuka, Tadashi

    2006-05-01

    Airborne geophysics can be defined as the measurement of Earth properties from sensors in the sky. The airborne measurement platform is usually a traditional fixed-wing airplane or helicopter, but could also include lighter-than-air craft, unmanned drones, or other specialty craft. The earliest history of airborne geophysics includes kite and hot-air balloon experiments. However, modern airborne geophysics dates from the mid-1940s when military submarine-hunting magnetometers were first used to map variations in the Earth's magnetic field. The current gamut of airborne geophysical techniques spans a broad range, including potential fields (both gravity and magnetics), electromagnetics (EM), radiometrics, spectral imaging, and thermal imaging.

  1. Subsidence related horizontal earth movements in the Tia Juana field, State of Zulia, Venezuela

    SciTech Connect

    Scherer, W.F.; Pedroza, M.A. )

    1990-05-01

    Subsidence due to oil exploitation in the Bolivar Coast fields in western Venezuela has been monitored since 1926. Related horizontal earth movements have been measured by geodetic methods during the last 10 yr in the northern Tia Juana field area in and around the Ule tank farm and the GLP gas liquefaction plant. Damage to storage tanks and increasing appearance of fractures in the ground in the vicinity of the coastal dyke protection system warranted a detailed study. A surface geologic survey of the Ule area, based initially on aerophotographic interpretation of infrared photographs, flown, on a 1:5,000 scale, showed the area to be divided into blocks by several major faults. These faults were confirmed on the ground by visual inspection, shallow seismic refraction, geoelectric surveys and correlation of geotechnical borings. A geodetic survey of the area with a precision of 5 mm + 2 mm/km for distances, showed significant horizontal displacements of ground markers during an eight-year period. Accordingly, a measuring plan of high-precision (0.015 mm) electromechanic extensometer lines was designed for critical zones across known fault traces and fracture zones. A conceptual model integrates geodetic and extensometer measurements of horizontal movements in the Ule area with the geologic and neotectonic frame of subsurface faults, joining systems, and tensional surface cracks. Rates of Holocene postglacial isostatic adjustments and natural, pre-industry subsidence due to degassing of reservoirs determined by C{sup 14} radiocarbon dating, were used to calculate subsidence rates due to oil exploitation. It was found that the subsidence occurs in the area, not as previously mapped continuous function of compaction, but as discrete, fault and crack limited blocks, governed as much by reactivation of fault slippage as by subsurface compaction.

  2. Movement.

    ERIC Educational Resources Information Center

    Roberts, Lynda S.

    This document summarizes 20 articles and books which stress the importance of movement in the overall development of the human species. Each summary ranges in length from 100 to 200 words and often includes direct quotations. A wide range of movement activities suitable for people of all ages (from infants to adults) are discussed. Many summaries…

  3. Research concerning the geophysical causes and measurement accuracies related to the irregularities in the rotation of the earth

    NASA Technical Reports Server (NTRS)

    Currie, D. G.

    1978-01-01

    The primary objective of this effort consisted of a detailed study of the history of the motion of the moon. Several analyses were developed which are related to the determination of the effect of various refractive phenomena on the accuracy of measurements made through the earth's atmosphere.

  4. Movement.

    ERIC Educational Resources Information Center

    Online-Offline, 1998

    1998-01-01

    Focuses on movement: movable art, relocating families, human rights, and trains and cars. Describes educational resources for elementary and middle school students, including Web sites, CD-ROMs and software, videotapes, books, additional resources and activities (PEN)

  5. Gravity and perceptual stability during translational head movement on earth and in microgravity.

    PubMed

    Jaekl, P; Zikovitz, D C; Jenkin, M R; Jenkin, H L; Zacher, J E; Harris, L R

    2005-01-01

    We measured the amount of visual movement judged consistent with translational head movement under normal and microgravity conditions. Subjects wore a virtual reality helmet in which the ratio of the movement of the world to the movement of the head (visual gain) was variable. Using the method of adjustment under normal gravity 10 subjects adjusted the visual gain until the visual world appeared stable during head movements that were either parallel or orthogonal to gravity. Using the method of constant stimuli under normal gravity, seven subjects moved their heads and judged whether the virtual world appeared to move "with" or "against" their movement for several visual gains. One subject repeated the constant stimuli judgements in microgravity during parabolic flight. The accuracy of judgements appeared unaffected by the direction or absence of gravity. Only the variability appeared affected by the absence of gravity. These results are discussed in relation to discomfort during head movements in microgravity. c2005 Elsevier Ltd. All rights reserved.

  6. A geophysical perspective on Earth's mantle water content: Inverting long-period electromagnetic sounding data using laboratory-based electrical conductivity profiles

    NASA Astrophysics Data System (ADS)

    Shankland, T. J.; Khan, A.

    2011-12-01

    We have applied electromagnetic sounding methods for Earth's mantle to constrain its thermal state, chemical composition, and "water" content. We consider long-period inductive response functionsin the form of C-responses from four stations distributed across the Earth (Europe, North America, Asia and Australia) covering a period range from 3.9 to 95.2 days and sensitivity to 1200 km depth. Rather than invert C-responses for conductivity profiles, we invert directly for chemical composition and thermal state using a self-consistent thermodynamic method to compute phase equilibria as functions of pressure, temperature, and composition (in the Na2O-CaO-FeO-MgO-Al2O3-SiO2 model system). Computed mineral modes are combined with recent laboratory-based electrical conductivity models from independent experimental research groups (Yoshino and coworkers and Karato and coworkers) to compute bulk conductivity structure beneath each of the four stations from which C-responses are estimated. This scheme is interfaced with a sampling-based algorithm to solve the resulting non-linear inverse problem. This approach has two advantages: (1) It anchors temperatures, composition, electrical conductivities, and discontinuities that are in laboratory-based forward models, and (2) At the same time it permits the use of geophysical inverse methods to optimize electrical profiles to match geophysical data. The results show variations in upper mantle temperatures beneath the four stations that appear to persist throughout the upper mantle and parts of the transition zone consistent with observations from seismic tomography images that show major lateral velocity variations in the upper mantle. Calculated mantle temperatures at 410 and 660 km depth lie in the range 1250-1650 deg C and 1500-1750 deg C, respectively, and generally agree with experimentally-determined temperatures at which the measured phase reactions olivine->beta-spinel and gamma-spinel->ferropericlase+perovskite occur. The

  7. Geophysical methods

    USDA-ARS?s Scientific Manuscript database

    Near-surface geophysical methods have become have become important tools for agriculture. Geophysics employed for agriculture tends to be heavily focused on a 2 m zone directly beneath the ground surface, which includes the crop root zone and all, or at least most, of the soil profile. Resistivity...

  8. Core Angular Momentum and the IERS Sub-Centers Activity for Monitoring Global Geophysical Fluids. Part 1; Core Angular Momentum and Earth Rotation

    NASA Technical Reports Server (NTRS)

    Song, Xia-Dong; Chao, Benjamin (Technical Monitor)

    1999-01-01

    The part of the grant was to use recordings of seismic waves travelling through the earth's core (PKP waves) to study the inner core rotation and constraints on possible density anomalies in the fluid core. The shapes and relative arrival times of such waves associated with a common source were used to reduce the uncertainties in source location and excitation and the effect of unknown mantle structure. The major effort of the project is to assemble historical seismograms with long observing base lines. We have found original paper records of SSI earthquakes at COL between 1951 and 1966 in a warehouse of the U.S. Geological Survey office in Golden, Colorado, extending the previous measurements at COL by Song and Richards [1996] further back 15 years. Also in Alaska, the University of Alaska, Fairbanks Geophysical Institute (UAFGI) has been operating the Alaskan Seismic Network with over 100 stations since the late 1960s. Virtually complete archives of seismograms are still available at UAFGI. Unfortunately, most of the archives are in microchip form (develocorders), for which the use of waveforms is impossible. Paper seismograms (helicorders) are available for a limited number of stations, and digital recordings of analog signals started around 1989. Of the paper records obtained, stations at Gilmore Dome (GLM, very close to COL), Yukon (FYU), McKinley (MCK), and Sheep Creek Mountain (SCM) have the most complete continuous recordings.

  9. Core Angular Momentum and the IERS Sub-Centers Activity for Monitoring Global Geophysical Fluids. Part 1; Core Angular Momentum and Earth Rotation

    NASA Technical Reports Server (NTRS)

    Song, Xia-Dong; Chao, Benjamin (Technical Monitor)

    1999-01-01

    The part of the grant was to use recordings of seismic waves travelling through the earth's core (PKP waves) to study the inner core rotation and constraints on possible density anomalies in the fluid core. The shapes and relative arrival times of such waves associated with a common source were used to reduce the uncertainties in source location and excitation and the effect of unknown mantle structure. The major effort of the project is to assemble historical seismograms with long observing base lines. We have found original paper records of SSI earthquakes at COL between 1951 and 1966 in a warehouse of the U.S. Geological Survey office in Golden, Colorado, extending the previous measurements at COL by Song and Richards [1996] further back 15 years. Also in Alaska, the University of Alaska, Fairbanks Geophysical Institute (UAFGI) has been operating the Alaskan Seismic Network with over 100 stations since the late 1960s. Virtually complete archives of seismograms are still available at UAFGI. Unfortunately, most of the archives are in microchip form (develocorders), for which the use of waveforms is impossible. Paper seismograms (helicorders) are available for a limited number of stations, and digital recordings of analog signals started around 1989. Of the paper records obtained, stations at Gilmore Dome (GLM, very close to COL), Yukon (FYU), McKinley (MCK), and Sheep Creek Mountain (SCM) have the most complete continuous recordings.

  10. Landolt-Börnstein. Numerical data and functional relationships inscience and technology. New Series. Group V: Geophysics and space research. Volume 2: Geophysics of the solid earth, the moon and the planets. Subvolume b.

    NASA Astrophysics Data System (ADS)

    Hellwege, K.-H.; Madelung, O.; Fuchs, K.; Soffel, H.; Chapman, D. S.; Lubimova, E. A.; Stacey, F. D.; Schmucker, U.; Haak, V.; Bosum, W.; Pucher, R.; Roeser, H.; Voppel, D.; Busse, F. H.; Hagedorn, H.; Gierloff-Emden, H. G.; Jacoby, W. R.

    Contents: Properties of the solid earth: Continental heat flow data (D. S. Chapman). Temperature profiles in the earth's interior (E. A. Lubimova). Heat transport in the earth's interior (F. D. Stacey). Electrical properties of the earth's interior (U. Schmucker, V. Haak). Magnetic fields of the earth (U. Schmucker, W. Bosum, R. Pucher, H. Roeser, D. Voppel,F. H. Busse, H. Soffel). Transport of masses in the earth's interior: Relief of the earth's surface and of the sea floor (H. Hagedorn, H. G. Gierloff-Emden). Theories and hypothesis of global tectonics (W. R. Jacoby).

  11. Agricultural Geophysics

    USDA-ARS?s Scientific Manuscript database

    The four geophysical methods predominantly used for agricultural purposes are resistivity, electromagnetic induction, ground penetrating radar (GPR), and time domain reflectometry (TDR). Resistivity and electromagnetic induction methods are typically employed to map lateral variations of apparent so...

  12. Exploration Geophysics

    ERIC Educational Resources Information Center

    Espey, H. R.

    1977-01-01

    Describes geophysical techniques such as seismic, gravity, and magnetic surveys of offshare acreage, and land-data gathering from a three-dimensional representation made from closely spaced seismic lines. (MLH)

  13. Exploration Geophysics

    ERIC Educational Resources Information Center

    Savit, Carl H.

    1978-01-01

    Expansion of activity and confirmation of new technological directions characterized several fields of exploration geophysics in 1977. Advances in seismic-reflection exploration have been especially important. (Author/MA)

  14. Exploration Geophysics

    ERIC Educational Resources Information Center

    Savit, Carl H.

    1978-01-01

    Expansion of activity and confirmation of new technological directions characterized several fields of exploration geophysics in 1977. Advances in seismic-reflection exploration have been especially important. (Author/MA)

  15. Exploration Geophysics

    ERIC Educational Resources Information Center

    Espey, H. R.

    1977-01-01

    Describes geophysical techniques such as seismic, gravity, and magnetic surveys of offshare acreage, and land-data gathering from a three-dimensional representation made from closely spaced seismic lines. (MLH)

  16. Deep mantle structure as a reference frame for movements in and on the Earth.

    PubMed

    Torsvik, Trond H; van der Voo, Rob; Doubrovine, Pavel V; Burke, Kevin; Steinberger, Bernhard; Ashwal, Lewis D; Trønnes, Reidar G; Webb, Susan J; Bull, Abigail L

    2014-06-17

    Earth's residual geoid is dominated by a degree-2 mode, with elevated regions above large low shear-wave velocity provinces on the core-mantle boundary beneath Africa and the Pacific. The edges of these deep mantle bodies, when projected radially to the Earth's surface, correlate with the reconstructed positions of large igneous provinces and kimberlites since Pangea formed about 320 million years ago. Using this surface-to-core-mantle boundary correlation to locate continents in longitude and a novel iterative approach for defining a paleomagnetic reference frame corrected for true polar wander, we have developed a model for absolute plate motion back to earliest Paleozoic time (540 Ma). For the Paleozoic, we have identified six phases of slow, oscillatory true polar wander during which the Earth's axis of minimum moment of inertia was similar to that of Mesozoic times. The rates of Paleozoic true polar wander (<1°/My) are compatible with those in the Mesozoic, but absolute plate velocities are, on average, twice as high. Our reconstructions generate geologically plausible scenarios, with large igneous provinces and kimberlites sourced from the margins of the large low shear-wave velocity provinces, as in Mesozoic and Cenozoic times. This absolute kinematic model suggests that a degree-2 convection mode within the Earth's mantle may have operated throughout the entire Phanerozoic.

  17. Optimization and geophysical inverse problems

    SciTech Connect

    Barhen, J.; Berryman, J.G.; Borcea, L.; Dennis, J.; de Groot-Hedlin, C.; Gilbert, F.; Gill, P.; Heinkenschloss, M.; Johnson, L.; McEvilly, T.; More, J.; Newman, G.; Oldenburg, D.; Parker, P.; Porto, B.; Sen, M.; Torczon, V.; Vasco, D.; Woodward, N.B.

    2000-10-01

    A fundamental part of geophysics is to make inferences about the interior of the earth on the basis of data collected at or near the surface of the earth. In almost all cases these measured data are only indirectly related to the properties of the earth that are of interest, so an inverse problem must be solved in order to obtain estimates of the physical properties within the earth. In February of 1999 the U.S. Department of Energy sponsored a workshop that was intended to examine the methods currently being used to solve geophysical inverse problems and to consider what new approaches should be explored in the future. The interdisciplinary area between inverse problems in geophysics and optimization methods in mathematics was specifically targeted as one where an interchange of ideas was likely to be fruitful. Thus about half of the participants were actively involved in solving geophysical inverse problems and about half were actively involved in research on general optimization methods. This report presents some of the topics that were explored at the workshop and the conclusions that were reached. In general, the objective of a geophysical inverse problem is to find an earth model, described by a set of physical parameters, that is consistent with the observational data. It is usually assumed that the forward problem, that of calculating simulated data for an earth model, is well enough understood so that reasonably accurate synthetic data can be generated for an arbitrary model. The inverse problem is then posed as an optimization problem, where the function to be optimized is variously called the objective function, misfit function, or fitness function. The objective function is typically some measure of the difference between observational data and synthetic data calculated for a trial model. However, because of incomplete and inaccurate data, the objective function often incorporates some additional form of regularization, such as a measure of smoothness

  18. Terrestrial Planet Geophysics

    NASA Astrophysics Data System (ADS)

    Phillips, R. J.

    2008-12-01

    Terrestrial planet geophysics beyond our home sphere had its start arguably in the early 1960s, with Keith Runcorn contending that the second-degree shape of the Moon is due to convection and Mariner 2 flying past Venus and detecting no planetary magnetic field. Within a decade, in situ surface geophysical measurements were carried out on the Moon with the Apollo program, portions of the lunar magnetic and gravity fields were mapped, and Jack Lorell and his colleagues at JPL were producing spherical harmonic gravity field models for Mars using tracking data from Mariner 9, the first spacecraft to orbit another planet. Moreover, Mariner 10 discovered a planetary magnetic field at Mercury, and a young Sean Solomon was using geological evidence of surface contraction to constrain the thermal evolution of the innermost planet. In situ geophysical experiments (such as seismic networks) were essentially never carried out after Apollo, although they were sometimes planned just beyond the believability horizon in planetary mission queues. Over the last three decades, the discipline of terrestrial planet geophysics has matured, making the most out of orbital magnetic and gravity field data, altimetric measurements of surface topography, and the integration of geochemical information. Powerful constraints are provided by tectonic and volcanic information gleaned from surface images, and the engagement of geologists in geophysical exercises is actually quite useful. Accompanying these endeavors, modeling techniques, largely adopted from the Earth Science community, have become increasingly sophisticated and have been greatly enhanced by the dramatic increase in computing power over the last two decades. The future looks bright with exciting new data sets emerging from the MESSENGER mission to Mercury, the promise of the GRAIL gravity mission to the Moon, and the re-emergence of Venus as a worthy target for exploration. Who knows? With the unflagging optimism and persistence

  19. Applied Geophysics

    NASA Astrophysics Data System (ADS)

    Telford, W. M.; Geldart, L. P.; Sheriff, R. E.

    1990-10-01

    Completely revised and updated, this new edition of the popular and highly regarded textbook, Applied Geophysics, describes the physical methods involved in exploration for hydrocarbons and minerals. These tools include gravity, magnetic, seismic, electrical, electromagnetic, and radioactivity studies. All aspects of these methods are described, including theoretical considerations, data acquisition, and data processing and interpretation, with the objective of locating concentrations of natural resources and defining their extent. In the past fourteen years or so since the writing of Applied Geophysics, there have been many changes in the field of exploration geophysics. The authors give full treatment to changes in this field, which include improved techniques for calculating gravity fields, the use of proton-precession and optically-pumped magnetometers, improved quality of seismic data, magnetotelluric as a practical exploration method, new electromagnetic exploration methods, the use of gamma-ray spectrometers in radioactive exploration, and improved well-logging techniques. The intent is to be practical, and thus many actual examples and problems are given. Moreover, wherever possible in this edition the authors adopt the use of Système Internationale (SI) units, which were not in standared use at the time of the first edition. The reader needs only a general background knowledge of geology, physics, and mathematics. Most of the math can be skipped by those interested only in the results. Advanced mathematical concepts are explained in the appendix.

  20. On the influence of the surface and body tides on the motion of a satellite. [earth geophysical aspects of orbit perturbations

    NASA Technical Reports Server (NTRS)

    Musen, P.

    1973-01-01

    Some geophysical aspects of the tidal perturbations in the motion of artificial satellites are investigated and a system of formulas is developed that is convenient for computation of the tidal effects in the elements using a step-by-step numerical integration.

  1. Applications of PTTI to new techniques for determining crustal movements, polar motion, and the rotation of the earth

    NASA Technical Reports Server (NTRS)

    Bender, P. L.

    1974-01-01

    New extra-terrestrial techniques are discussed for geodesy and geodynamics include laser range measurements to the moon or to artificial satellites, Doppler measurements with the Transit satellite system, and both independent-clock and linked-antenna microwave interferometry. The ways in which PTTI measurements are used in these techniques will be reviewed, and the accuracies expected during the latter half of the 1970's will be discussed. At least 3 of the techniques appear capable of giving accuracies of 5 cm or better in each coordinate for many points on the earth's surface, and comparable accuracies for the earth's rotation and polar motion. For fixed stations or for sites a few hundred km apart, baseline lengths accurate to 1 cm may be achieved. Ways in which the complementary aspects of the different techniques can be exploited will be discussed, as well as how they tie in with improved ground techniques for determining crustal movements. Some recent results from the extra-terrestrial methods will be mentioned.

  2. Reports on crustal movements and deformations

    NASA Astrophysics Data System (ADS)

    Cohen, S. C.; Peck, T.

    1983-05-01

    This Catalog of Reports on Crustal Movements and Deformation is a structured bibliography of scientific papers on the movements of the Earth crust. The catalog summarizes by various subjects papers containing data on the movement of the Earth's surface due to tectonic processes. In preparing the catalog we have included studies of tectonic plate motions, spreading and convergence, microplate rotation, regional crustal deformation strain accumulation and deformations associated with the earthquake cycle, and fault motion. We have also included several papers dealing with models of tectonic plate motion and with crustal stress. Papers which discuss tectonic and geologic history but which do not present rates of movements or deformations and papers which are primarily theoretical analyses have been excluded from the catalog. An index of authors cross-referenced to their publications also appears in the catalog. The catalog covers articles appearing in reviewed technical journals during the years 1970-1981. Although there are citations from about twenty journals most of the items come from the following publications: Journal of Geophysical Research, Tectonophysics, Geological Society of America Bulletin of the Seismological Society of America, Nature, Science, Geophysical Journal of the Royal Astronomical Society, Earth and Planetary Science Letters, and Geology.

  3. Reports on crustal movements and deformations. [bibliography

    NASA Technical Reports Server (NTRS)

    Cohen, S. C.; Peck, T.

    1983-01-01

    This Catalog of Reports on Crustal Movements and Deformation is a structured bibliography of scientific papers on the movements of the Earth crust. The catalog summarizes by various subjects papers containing data on the movement of the Earth's surface due to tectonic processes. In preparing the catalog we have included studies of tectonic plate motions, spreading and convergence, microplate rotation, regional crustal deformation strain accumulation and deformations associated with the earthquake cycle, and fault motion. We have also included several papers dealing with models of tectonic plate motion and with crustal stress. Papers which discuss tectonic and geologic history but which do not present rates of movements or deformations and papers which are primarily theoretical analyses have been excluded from the catalog. An index of authors cross-referenced to their publications also appears in the catalog. The catalog covers articles appearing in reviewed technical journals during the years 1970-1981. Although there are citations from about twenty journals most of the items come from the following publications: Journal of Geophysical Research, Tectonophysics, Geological Society of America Bulletin of the Seismological Society of America, Nature, Science, Geophysical Journal of the Royal Astronomical Society, Earth and Planetary Science Letters, and Geology.

  4. The Earth's Shape and Movements: Teachers' Perception of the Relations Between Daily Observation and Scientific Models

    NASA Astrophysics Data System (ADS)

    Ferreira, Flávia Polati; Leite, Cristina

    2015-07-01

    The Earth’s shape and movements are some of the most common issues in official documents and research studies of astronomy education. Many didactic proposals suggest these issues within observational astronomy. Therefore, we present in this paper some of the main results of a research study of the teachers’ perception of the relations between the knowledge from daily observation and scientific models currently accepted about the “earth’s shape and movements”. Data were obtained in application of the didactic proposal during a teacher training course for teachers from São Paulo, have been constructed with the dynamics “Three Pedagogical Moments” and guided by some of the central ideas of the educator Paulo Freire. The results indicate that a small proportion of teachers seem to understand some of the relations of “apparent contradictions” and “limitations” with the concepts of spatiality, and many of them argued based only on vague phrases or "buzzwords", unconnected to the problem explored. The difficulties of teachers to relate elements of daily observation with scientific models seem to indicate a necessity to approach some these aspects with the astronomical knowledge in the teacher training courses.

  5. Teaching Future Teachers Basic Astronomy Concepts--Sun-Earth-Moon Relative Movements--at a Time of Reform in Science Education

    ERIC Educational Resources Information Center

    Trumper, Ricardo

    2006-01-01

    In view of students' alternative conceptions about basic concepts in astronomy, we conducted a series of constructivist activities with future elementary and junior high school teachers aimed at changing their conceptions about the cause of seasonal changes, and of several characteristics of the Sun-Earth-Moon relative movements like Moon phases,…

  6. Teaching Future Teachers Basic Astronomy Concepts--Sun-Earth-Moon Relative Movements--at a Time of Reform in Science Education

    ERIC Educational Resources Information Center

    Trumper, Ricardo

    2006-01-01

    In view of students' alternative conceptions about basic concepts in astronomy, we conducted a series of constructivist activities with future elementary and junior high school teachers aimed at changing their conceptions about the cause of seasonal changes, and of several characteristics of the Sun-Earth-Moon relative movements like Moon phases,…

  7. A Systematic Review of the Health Impacts of Mass Earth Movements (Landslides)

    PubMed Central

    Kennedy, Iain T R; Petley, Dave N.; Williams, Richard; Murray, Virginia

    2015-01-01

    Background. Mass ground movements (commonly referred to as ‘landslides’) are common natural hazards that can have significant economic, social and health impacts. They occur as single events, or as clusters, and are often part of ‘disaster’ chains, occurring secondary to, or acting as the precursor of other disaster events. Whilst there is a large body of literature on the engineering and geological aspects of landslides, the mortality and morbidity caused by landslides is less well documented. As far as we are aware, this is the first systematic review to examine the health impacts of landslides. Methods. The MEDLINE, EMBASE, CINAHL, SCOPUS databases and the Cochrane library were systematically searched to identify articles which considered the health impacts of landslides. Case studies, case series, primary research and systematic reviews were included. News reports, editorials and non-systematic reviews were excluded. Only articles in English were considered. The references of retrieved papers were searched to identify additional articles. Findings. 913 abstracts were reviewed and 143 full text articles selected for review. A total of 27 papers reporting research studies were included in the review (25 from initial search, 1 from review of references and 1 from personal correspondence). We found a limited number of studies on the physical health consequences of landslides. Only one study provided detail of the causes of mortality and morbidity in relation a landslide event. Landslides cause significant mental health impacts, in particular the prevalence of PTSD may be higher after landslides than other types of disaster, though these studies tend to be older with only 3 papers published in the last 5 years, with 2 being published 20 years ago, and diagnostic criteria have changed since they were produced. Discussion. We were disappointed at the small number of relevant studies, and the generally poor documentation of the health impacts of landslides

  8. A systematic review of the health impacts of mass Earth movements (landslides).

    PubMed

    Kennedy, Iain T R; Petley, Dave N; Williams, Richard; Murray, Virginia

    2015-04-30

    Background. Mass ground movements (commonly referred to as 'landslides') are common natural hazards that can have significant economic, social and health impacts. They occur as single events, or as clusters, and are often part of 'disaster' chains, occurring secondary to, or acting as the precursor of other disaster events. Whilst there is a large body of literature on the engineering and geological aspects of landslides, the mortality and morbidity caused by landslides is less well documented. As far as we are aware, this is the first systematic review to examine the health impacts of landslides. Methods. The MEDLINE, EMBASE, CINAHL, SCOPUS databases and the Cochrane library were systematically searched to identify articles which considered the health impacts of landslides. Case studies, case series, primary research and systematic reviews were included. News reports, editorials and non-systematic reviews were excluded. Only articles in English were considered. The references of retrieved papers were searched to identify additional articles. Findings. 913 abstracts were reviewed and 143 full text articles selected for review. A total of 27 papers reporting research studies were included in the review (25 from initial search, 1 from review of references and 1 from personal correspondence). We found a limited number of studies on the physical health consequences of landslides. Only one study provided detail of the causes of mortality and morbidity in relation a landslide event. Landslides cause significant mental health impacts, in particular the prevalence of PTSD may be higher after landslides than other types of disaster, though these studies tend to be older with only 3 papers published in the last 5 years, with 2 being published 20 years ago, and diagnostic criteria have changed since they were produced. Discussion. We were disappointed at the small number of relevant studies, and the generally poor documentation of the health impacts of landslides. Mental

  9. SAGE celebrates 25 years of learning geophysics by doing geophysics

    USGS Publications Warehouse

    Jiracek, G.R.; Baldridge, W.S.; Sussman, A.J.; Biehler, S.; Braile, L.W.; Ferguson, J.F.; Gilpin, B.E.; McPhee, D.K.; Pellerin, L.

    2008-01-01

    The increasing world demand and record-high costs for energy and mineral resources, along with the attendant environmental and climate concerns, have escalated the need for trained geophysicists to unprecedented levels. This is not only a national need; it's a critical global need. As Earth scientists and educators we must seriously ask if our geophysics pipeline can adequately address this crisis. One program that has helped to answer this question in the affirmative for 25 years is SAGE (Summer of Applied Geophysical Experience). SAGE continues to develop with new faculty, new collaborations, and additional ways to support student participation during and after SAGE. ?? 2008 Society of Exploration Geophysicists.

  10. Short-term and Imminent Precursors of Haiti M7.0 Earthquake: Earth Degassing and Thermal Vortex Rotated Movement

    NASA Astrophysics Data System (ADS)

    Qiang, Z.; Qiang, J.; Zeng, Z.; Wang, J.; Xie, H.

    2010-12-01

    The introduction of fracture theory in geology into seismology is hindering the development of seismology and impeding the progress of earthquake forecast. The study of thermal infrared images of the same time but on different days, 30 days prior to the earthquake, one at 17:45:14,Dec.10 UTC,2009 and the other at 17:45:14,Dec.14 UTC,2009, shows that the brightness temperature increases from 296-297°C into 302-303°C in the Cuba Ils., Haiti Isl. Of Gulf of Mexico and Caribbean Sea and adjacent area. The area of temperature increase takes the shape of an elliptic circle 4000Km long in the NW direction and 1000Km wide in the NE direction with an area of about 4,000,000Km2 . P axis is stretch in NNE21° direction. The strike of the fracture is NW 3300. The elliptic circle structure had left handed rotation. 12 to 10days before the quake the cloud belt had extended from Port-au-Prince into Atlantic ocean(25°N,-31.5W)with its width of 50-100Km and lasted more than 50 hours. Earthquake can be predicted using the satellite thermal infrared brightness temperature anomalous method and combining the method of array of infrasonic instruments. The autors thank Dr. Helen Wood, former Chairman of CEOS (Committee of Earth Observation Satellite) and Dr. Axel Graumann of NOAA for providing the satellite images used in this study. Thermal Vortex Rotated Movement and Structure Prior to Haiti Earthquake Earth degassing from the epicenter of Haiti Earthquake, Clould belt extends 4,000 km for 50 hours.

  11. Strategies for improving the resolution of electrical and electromagnetic geophysical measurements for three-dimensional inverse modeling of CO2 movement

    NASA Astrophysics Data System (ADS)

    Commer, M.; Kowalsky, M. B.; Dafflon, B.; Wu, Y.; Hubbard, S. S.

    2013-12-01

    Geologic carbon sequestration is being evaluated as a means to mitigate the effects of greenhouse gas emissions. Efforts are underway to identify adequate reservoirs and to evaluate the behavior of injected CO2 over time; time-lapse geophysical methods are considered effective tools for these purposes. Pilot studies have shown that the invasion of CO2 into a background pore fluid can alter the electrical resistivity, with increases from CO2 in the super-critical or gaseous phase, and decreases from CO2 dissolved in groundwater (especially when calcite dissolution is occurring). Because of their sensitivity to resistivity changes, electrical and electromagnetic (EM) methods have been used in such studies for indirectly assessing CO2 saturation changes. While the electrical resistance tomography (ERT) method is a well-established technique for both crosswell and surface applications, its usefulness is limited by the relatively low-resolution information it provides. Controlled-source EM methods, including both frequency-domain and time-domain (transient EM) methods, can offer improved resolution. We report on three studies that aim to maximize the information content of electrical and electromagnetic measurements in inverse modeling applications that target the monitoring of resistivity changes due to CO2 migration and/or leakage. The first study considers a three-dimensional crosswell data set collected at an analogue site used for investigating CO2 distribution and geochemical reactivity within a shallow formation. We invert both resistance and phase data using a gradient-weighting method for descent-based inversion algorithms. This method essentially steers the search direction in the model space using low-cost non-linear conjugate gradient methods towards the more computationally expensive Gauss-Newton direction. The second study involves ERT data that were collected at the SECARB Cranfield site near Natchez, Mississippi, at depths exceeding 3000 m. We employ a

  12. Earth

    NASA Image and Video Library

    2012-01-30

    Behold one of the more detailed images of the Earth yet created. This Blue Marble Earth montage shown above -- created from photographs taken by the Visible/Infrared Imager Radiometer Suite (VIIRS) instrument on board the new Suomi NPP satellite -- shows many stunning details of our home planet. The Suomi NPP satellite was launched last October and renamed last week after Verner Suomi, commonly deemed the father of satellite meteorology. The composite was created from the data collected during four orbits of the robotic satellite taken earlier this month and digitally projected onto the globe. Many features of North America and the Western Hemisphere are particularly visible on a high resolution version of the image. http://photojournal.jpl.nasa.gov/catalog/PIA18033

  13. Serious games for Geophysics

    NASA Astrophysics Data System (ADS)

    Lombardo, Valerio; Rubbia, Giuliana

    2015-04-01

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

  14. Continental crust: a geophysical approach

    SciTech Connect

    Meissner, R.

    1986-01-01

    This book develops an integrated and balanced picture of present knowledge of the continental crust. Crust and lithosphere are first defined, and the formation of crusts as a general planetary phenomenon is described. The background and methods of geophysical studies of the earth's crust and the collection of related geophysical parameters are examined. Creep and friction experiments and the various methods of radiometric age dating are addressed, and geophysical and geological investigations of the crustal structure in various age provinces of the continents are studied. Specific tectonic structures such as rifts, continental margins, and geothermal areas are discussed. Finally, an attempt is made to give a comprehensive view of the evolution of the continental crust and to collect and develop arguments for crustal accretion and recycling. 647 references.

  15. Geophysics benefits

    NASA Astrophysics Data System (ADS)

    An agreement signed May 6 between the U.S. and the U.S.S.R. creates new opportunities for joint geophysical research programs. Dallas Peck, director of the U.S. Geological Survey, and Erich Bloch, director of the National Science Foundation signed two agreements for basic scientific research with the Soviets to establish links between between the U.S. Geological Survey and the Soviet Ministry of Geology and between the National Science Foundation and the Soviet Academy of Sciences. The USGS agreement also establishes a connection with the Soviet Academy of Sciences.The Memoranda of Understanding are the first to be developed under the Agreement on Cooperation in the Field of Basic Scientific Research signed in January, by then Secretary of State George Shultz and Soviet Foreign Minister Eduard Shevardnadze. The agreements address cooperation in basic rather than applied science and establish a formal mechanism for access to research facilities and support involving NSF, universities, the Soviet Academy of Sciences, USGS, and the Soviet Ministry of Geology.

  16. The Teach for America RockCorps, Year 2: Using Authentic Research Experiences in Geophysics for STEM Teachers to Inspire Earth Science-Themed Lessons in High School Classrooms

    NASA Astrophysics Data System (ADS)

    Parsons, B.; Kassimu, R.; Borjas, C. N.; Griffith, W. A.

    2016-12-01

    Brooke Parsons1, Rahmatu Kassimu2, Christopher Borjas3, and W. Ashley Griffith31Uplift Hampton Preparatory High School, Dallas, TX, 75232 2H. Grady Spruce High School, Dallas, TX, 75217 3Department of Earth and Environmental Sciences, University of Texas Arlington, Arlington, TX, 76019 As Earth Science courses appear in fewer high school curricula, we seek to find creative ways to integrate Earth Science themes as contextual examples into other K-12 STEM courses in order to develop (A) Earth Science literacy, and (B) a pipeline of young talent into our field. This presentation details the efforts of the 2nd year Teach for America (TFA) Rock Corps, a five year NSF-sponsored partnership between TFA and the University of Texas at Arlington designed to provide STEM teachers with genuine research opportunities using components that can be extrapolated to develop dynamic Geophysics-themed lesson plans and materials for their classrooms. Two teachers were selected from the Dallas-Fort Worth region of TFA to participate in original research modeling off-fault damage that occurs during earthquakes in a lab setting using a Split-Hopkinson-Pressure Bar (SHPB). In particular, we simulate a coseismic transient stress perturbation in a fault damage zone by combining traditional SHPB with a traveling harmonic oscillator: Two striker bars attached by an elastic spring are launched with a gas gun allowing us to create the double stress pulse expected during an earthquake rupture. This research affords teachers inspiration to implement Geophysics-themed lesson plans for their courses, Physics/Pre-AP Physics and Chemistry. The physics course will adopt principles of seismic wave propagation to teach concepts of impulse, momentum, conservation of energy, harmonic motion, wave velocity, wave propagation, and real world applications of waves. The chemistry course will implement geochemistry themed techniques into applying the scientific method, density, isotopic composition, p

  17. On the similarity of 239Pu α-activity histograms when the angular velocities of the Earth diurnal rotation, orbital movement and rotation of collimators are equalized

    NASA Astrophysics Data System (ADS)

    Shnoll, S. E.; Rubinstein, I. A.; Shapovalov, S. N.; Tolokonnikova, A. A.; Shlektaryov, V. A.; Kolombet, V. A.; Kondrashova, M. N.

    2016-01-01

    It was shown earlier that the persistent "scatter" of results of measurements of any nature is determined by the diurnal and orbital movement of the Earth. The movement is accompanied by "macroscopic fluctuations" (MF)—regular, periodic changes in the shape of histograms, spectra of fluctuation amplitudes of the measured parameters. There are two near-daily periods ("sidereal", 1436 min; and "solar", 1440 min) and three yearly ones ("calendar", 365 average solar days; "tropical", 365 days 5 h and 48 min; and "sidereal", 365 days 6 h and 9 min). This periodicity was explained by the objects whose parameters are measured passing through the same spatial-temporal heterogeneities as the Earth rotates and shifts along its orbit.

  18. Studies in geophysics: Active tectonics

    NASA Technical Reports Server (NTRS)

    1986-01-01

    Active tectonics is defined within the study as tectonic movements that are expected to occur within a future time span of concern to society. Such movements and their associated hazards include earthquakes, volcanic eruptions, and land subsidence and emergence. The entire range of geology, geophysics, and geodesy is, to some extent, pertinent to this topic. The needs for useful forecasts of tectonic activity, so that actions may be taken to mitigate hazards, call for special attention to ongoing tectonic activity. Further progress in understanding active tectonics depends on continued research. Particularly important is improvement in the accuracy of dating techniques for recent geologic materials.

  19. Geophysics in petroleum exploration

    SciTech Connect

    Not Available

    1984-01-01

    There were 40,000 professionals involved in geophysical exploration for oil and gas during 1982, and they spent nearly $3 billion, mostly on seismic surveys. This brochure explains petroleum geology in terms of earth dynamics and petroleum deposits. It explains gravity, magnetic, and seismic surveys and the use of computers to search for oil and gas. The information covers both onshore and offshore surveying, the technology involved, the processing of seismic data, and the development of maps and models. The temporary nature of petroleum exploration introduces the need for environmental protection which is site specific. The technology is available for continued exploration, but impediments to exploration on public lands and at offshore sites need to be removed for both economic and national security reasons. 3 references, 30 figures.

  20. Geophysics of Mars

    NASA Technical Reports Server (NTRS)

    Wells, R. A.

    1979-01-01

    A physical model of Mars is presented on the basis of light-scattering observations of the Martian atmosphere and surface and interior data obtained from observations of the geopotential field. A general description of the atmosphere is presented, with attention given to the circulation and the various cloud types, and data and questions on the blue haze-clearing effect and the seasonal darkening wave are summarized and the Mie scattering model developed to explain these observations is presented. The appearance of the planet from earth and spacecraft through Mariner 9 is considered, and attention is given to the preparation of topographical contour maps, the canal problem and large-scale lineaments observed from Mariner 9, the gravity field and shape of the planet and the application of Runcorn's geoid/convection theory to Mars. Finally, a summary of Viking results is presented and their application to the understanding of Martian geophysics is discussed.

  1. Geophysics of Mars

    NASA Technical Reports Server (NTRS)

    Wells, R. A.

    1979-01-01

    A physical model of Mars is presented on the basis of light-scattering observations of the Martian atmosphere and surface and interior data obtained from observations of the geopotential field. A general description of the atmosphere is presented, with attention given to the circulation and the various cloud types, and data and questions on the blue haze-clearing effect and the seasonal darkening wave are summarized and the Mie scattering model developed to explain these observations is presented. The appearance of the planet from earth and spacecraft through Mariner 9 is considered, and attention is given to the preparation of topographical contour maps, the canal problem and large-scale lineaments observed from Mariner 9, the gravity field and shape of the planet and the application of Runcorn's geoid/convection theory to Mars. Finally, a summary of Viking results is presented and their application to the understanding of Martian geophysics is discussed.

  2. Geophysical Fluid Dynamics

    NASA Astrophysics Data System (ADS)

    Busse, F. H.

    In the past 8 years, since Pedlosky's book was first published, it has found a well established place in the literature of dynamical meteorology and physical oceanography. Geophysicists less familiar with these fields may need to be reminded that the subject of geophysical fluid dynamics, in the narrow definition used in the title of the book, refers to the theory of the large-scale motions of the atmosphere and the oceans. Topics such as thermal convection in the atmosphere or in Earth's mantle and core are not treated in this book, and the reader will search in vain for a discussion of atmospheric or oceanic tides. The theory of quasi-geostrophic flow is described comprehensively, however, and its major applications to problems of atmospheric and oceanic circulations are considered in detail.

  3. Geophysical Sounding

    NASA Astrophysics Data System (ADS)

    Blake, E.

    1998-01-01

    Of the many geophysical remote-sensing techniques available today, a few are suitable for the water ice-rich, layered material expected at the north martian ice cap. Radio echo sounding has been used for several decades to determine ice thickness and internal structure. Selection of operating frequency is a tradeoff between signal attenuation (which typically increases with frequency and ice temperature) and resolution (which is proportional to wavelength). Antenna configuration and size will be additional considerations for a mission to Mars. Several configurations for ice-penetrating radar systems are discussed: these include orbiter-borne sounders, sounding antennas trailed by balloons and penetrators, and lander-borne systems. Lander-borne systems could include short-wave systems capable of resolving fine structure and layering in the upper meters beneath the lander. Spread-spectrum and deconvolution techniques can be used to increase the depth capability of a radar system. If soundings over several locations are available (e.g., with balloons, rovers, or panning short-wave systems), then it will be easier to resolve internal layering, variations in basal reflection coefficient (from which material properties may be inferred), and the geometry of nonhorizontal features. Sonic sounding has a long history in oil and gas exploration. It is, however, unlikely that large explosive charges, or even swept-frequency techniques such as Vibroseis, would be suitable for a Polar lander -- these systems are capable of penetrating several kilometers of material at frequencies of 10-200 Hz, but the energy required to generate the sound waves is large and potentially destructive. The use of audio-frequency and ultrasonic sound generated by piezoelectric crystals is discussed as a possible method to explore layering and fine features in the upper meters of the ice cap. Appropriate choice of transducer(s) will permit operation over a range of fixed or modulated frequencies

  4. Sustainable urban development and geophysics

    NASA Astrophysics Data System (ADS)

    Liu, Lanbo; Chan, L. S.

    2007-09-01

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

  5. Recommended reference figures for geophysics and geodesy

    NASA Technical Reports Server (NTRS)

    Khan, M. A.; Okeefe, J. A.

    1973-01-01

    Specific reference figures are recommended for consistent use in geophysics and geodesy. The selection of appropriate reference figure for geophysical studies suggests a relationship between the Antarctic negative gravity anomaly and the great shrinkage of the Antarctic ice cap about 4-5 million years ago. The depression of the south polar regions relative to the north polar regions makes the Southern Hemisphere flatter than the Northern Hemisphere, thus producing the third harmonic (pear-shaped) contribution to the earth's figure.

  6. Foundations of Nuclear Geophysics

    NASA Astrophysics Data System (ADS)

    Herndon, J. M.; Hollenbach, D. F.

    2002-05-01

    Herndon suggested that the inner core of the Earth consists, not of partially crystallized iron metal, but of nickel silicide. He has shown by fundamental mass ratios that i) the Earth as a whole, especially the inner 82%, has a state of oxidation like primitive enstatite chondrites, and ii) the lower mantle and core are similar in composition to the Abee enstatite chondrite. By analogy with Abee data, CaS and MgS precipitates from the core are expected to collect at the core-mantle boundary and, significantly, a major fraction of the actinides are expected to precipitate from the core and to collect at the center of the Earth. Herndon demonstrated the feasibility of a nuclear fission reactor at the center of the Earth as the energy source for the geomagnetic field and described a natural mechanism that would lead to variations in energy production and thus variations in the geomagnetic field. Hollenbach and Herndon produced numerical simulations of the operation of the geo-reactor over the lifetime of the Earth using the state-of-the-art, validated, industry standard SCALE code package developed at Oak Ridge National Laboratory. The results clearly demonstrate that such a geo-reactor would i) function as a fast-neutron breeder reactor; ii) under appropriate conditions, operate over the entire period of geologic time; iii) function in such a manner as to yield variable and/or intermittent output; iv) generate energy at levels in the range generally accepted by the geophysics community; and, v) produce He-3 and He-4 in ratios that are in the range observed from deep-mantle sources. Deep-source He-3, the authors submit, is evidence of in-core sustained nuclear fission, rather than the out-gassing of primordial He-3; which in turn is evidence of large amounts of uranium residing in the Earth's core; which in turn is evidence that the core has a state of oxidation like the corresponding matter in primitive enstatite chondrites. The factors affecting He-3/He-4 ratios

  7. 15 CFR 950.5 - National Geophysical and Solar-Terrestrial Data Center (NGSDC).

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...-A (Solid-Earth Geophysics, Solar Terrestrial Physics, and Glaciology). (a) Geophysical and solar... geological data, including data on heat flow, cores, samples, and sediments. (2) Solar-Terrestrial physics...

  8. 15 CFR 950.5 - National Geophysical and Solar-Terrestrial Data Center (NGSDC).

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...-A (Solid-Earth Geophysics, Solar Terrestrial Physics, and Glaciology). (a) Geophysical and solar... geological data, including data on heat flow, cores, samples, and sediments. (2) Solar-Terrestrial physics...

  9. 15 CFR 950.5 - National Geophysical and Solar-Terrestrial Data Center (NGSDC).

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...-A (Solid-Earth Geophysics, Solar Terrestrial Physics, and Glaciology). (a) Geophysical and solar... geological data, including data on heat flow, cores, samples, and sediments. (2) Solar-Terrestrial physics...

  10. 15 CFR 950.5 - National Geophysical and Solar-Terrestrial Data Center (NGSDC).

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...-A (Solid-Earth Geophysics, Solar Terrestrial Physics, and Glaciology). (a) Geophysical and solar... geological data, including data on heat flow, cores, samples, and sediments. (2) Solar-Terrestrial physics...

  11. 15 CFR 950.5 - National Geophysical and Solar-Terrestrial Data Center (NGSDC).

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...-A (Solid-Earth Geophysics, Solar Terrestrial Physics, and Glaciology). (a) Geophysical and solar... geological data, including data on heat flow, cores, samples, and sediments. (2) Solar-Terrestrial physics...

  12. Air-depolyable geophysics package

    SciTech Connect

    Hunter, S.L.; Harben, P.E.

    1993-11-01

    We are using Lawrence Livermore National Laboratory`s (LLNL`s) diverse expertise to develop a geophysical monitoring system that can survive being dropped into place by a helicopter or airplane. Such an air-deployable system could significantly decrease the time and effort needed to set up such instruments in remote locations following a major earthquake or volcanic eruption. Most currently available geophysical monitoring and survey systems, such as seismic monitoring stations, use sensitive, fragile instrumentation that requires personnel trained and experienced in data acquisition and field setup. Rapid deployment of such equipment can be difficult or impossible. Recent developments in low-power electronics, new materials, and sensors that are resistant to severe impacts have made it possible to develop low-cost geophysical monitoring packages for rapid deployment missions. Our strategy was to focus on low-cost battery-powered systems that would have a relatively long (several months) operational lifetime. We concentrated on the conceptual design and engineering of a single-component seismic system that could survive an air-deployment into an earth material, such as alluvium. Actual implementation of such a system is a goal of future work on this concept. For this project, we drew on LLNL`s Earth Sciences Department, Radio Shop, Plastics Shop, and Weapons Program. The military has had several programs to develop air-deployed and cannon-deployed seismometers. Recently, a sonobuoy manufacturer has offered an air-deployable geophone designed to make relatively soft landings.

  13. Handbook of Agricultural Geophysics

    USDA-ARS?s Scientific Manuscript database

    Geophysical methods continue to show great promise for use in agriculture. The term “agricultural geophysics” denotes a subdiscipline of geophysics that is focused only on agricultural applications. The Handbook of Agricultural Geophysics was compiled to include a comprehensive overview of the geoph...

  14. Demonstrations in Introductory Geophysics

    NASA Astrophysics Data System (ADS)

    Schramm, K. A.; Stein, S.; van der Lee, S.; Swafford, L.; Klosko, E.; Delaughter, J.; Wysession, M.

    2005-12-01

    Geophysical concepts are challenging to teach at introductory levels, because students need to understand both the underlying physics and its geological application. To address this, our introductory courses include class demonstrations and experiments to demonstrate underlying physical principles and their geological applications. Demonstrations and experiments have several advantages over computer simulations. First, computer simulations "work" even if the basic principle is wrong. In contrast, simple demonstrations show that a principle is physically correct, rather than a product of computer graphics. Second, many students are unfamiliar with once-standard experiments demonstrating ideas of classical physics used in geophysics. Demonstrations are chosen that we consider stimulating, relevant, inexpensive, and easy to conduct in a non-lab classroom. These come in several groups. Many deal with aspects of seismic waves, using springs, light beams, and other methods such as talking from outside the room to illustrate the frequency dependence of diffraction (hearing but not seeing around a corner). Others deal with heat and mass transfer, such as illustrating fractional crystallization with apple juice and the surface/volume effect in planetary evolution with ice. Plate motions are illustrated with paper cutouts showing effects like motion on transform faults and how the Euler vector geometry changes a plate boundary from spreading, to strike-slip, to convergence along the Pacific-North America boundary from the Gulf of California to Alaska. Radioactive decay is simulated by having the class rise and sit down as a result of coin flips (one tail versus two gives different decay rates and hence half lives). This sessions' goal of exchanging information about demonstrations is an excellent idea: some of ours are described on http://www.earth.nwu.edu/people/seth/202.

  15. Developing a curricular module for introductory geophysics or structural geology courses to quantify crustal strain using EarthScope PBO GPS velocities

    NASA Astrophysics Data System (ADS)

    Cronin, V. S.; Resor, P. G.; Hammond, W. C.; Kreemer, C. W.; Olds, S. E.; Pratt-Sitaula, B.; West, N. W.

    2012-12-01

    A group from several UNAVCO-member institutions that are engaged in EarthScope research is developing resources that introduce geoscience majors to one important use of GPS geodesy: measuring the current infinitesimal strain rate of the crust. These resources will be tested during the 2012-13 academic year, and will be accessible from the Science Education Resource Center (SERC), UNAVCO and EarthScope websites. Location and velocity data (and their associated uncertainties) from the EarthScope Plate Boundary Observatory (PBO) website are used to solve a perfectly constrained problem involving the infinitesimal strain of a triangle defined by three PBO GPS sites. Simple physical models made of inexpensive materials are used to build student intuition about homogeneous strain of a continuum. Introductory exercises with vector-field maps are used to help students understand reference frames and visualize how GPS velocity vectors can indicate crustal strain. The meanings of "extension" and "stretch" are developed through illustrations showing the simultaneous deformation of a triangle with a circle inscribed within it. A strain primer, intended to supplement textbook material, is provided for students to develop needed background. Supplemental material about vectors, vector dot products, matrix mathematics, determinants, and computation of the eigensystem of a symmetric square matrix help support students who have gaps in their mathematical background. Students compute site velocities and uncertainties from PBO data, insert data into one of three strain calculators (open-source code in MatLab, Mathematica, and an Excel spreadsheet), and learn to interpret the output. A complete algorithm and worked example are also provided so that capable students can develop their own code to solve the problem. Strain calculator output includes the mean translation velocity vector, the rotational velocity, the relative magnitudes and directions of the horizontal infinitesimal strain

  16. Progress in geophysical fluid dynamics

    NASA Astrophysics Data System (ADS)

    Robinson, Allan R.

    Geophysical fluid dynamics deals with the motions and physics of the atmosphere, oceans and interior of the earth and other planets: the winds, the swirls, the currents that occur on myriads of scales from millimeter to climatological. Explanations of natural phenomena, basic processes and abstractions are sought. The rotation of the earth, the buoyancy of its fluids and the tendency towards large-scale turbulence characterize these flows. But geophysical fluid dynamics is importantly a part of modern fluid dynamics which is contributing to the development of nonlinear mechanics generally. Some general insights are emerging for nonlinear systems which must be regarded as partly deterministic and partly random or which are complex and aperiodic. Contributions from geophysical fluid dynamics come from its methodology, from the experience of examples, and from the perspective provided by its unique scale. Contributions have been made to turbulent, chaotic and coherently structured nonlinear process research. Turbulent vortices larger than man himself naturally invite detailed investigation and deterministic physical studies. Examples are storms in the atmosphere and large ring vortices spun off by the Gulf Stream current in mid-ocean. The statistics of these events determine critical aspects of the general circulations. Fluid dynamicists generally now know that it is often relevant or necessary to study local dynamical processes of typical eddies even though only the average properties of the flow are of interest; progress in understanding the turbulent boundary layer in pipes involves the study of millimeter-scale vortices. Weather-related studies were seminal to the construction of the new scientific field of chaos. Coherent vortices abound of which the Great Red Spot of Jupiter is a spectacular example. Geophysical fluid dynamicists have been among forefront researchers in exploiting the steadily increasing speed and capacity of modern computers. Supercomputers

  17. Earth Observing System, Introduction

    NASA Technical Reports Server (NTRS)

    1983-01-01

    Much is known about the Earth, but the unifying concepts are still only beginning to be established. An exposition of the key issues in Earth science is neither simple or concise. From the scientific questions at hand there are many interconnections among them and the view of the Earth as a system is essential to their solution. The Earth science goals for the 1990's are presented for the following areas: hydrologic cycle; biogeochemical cycles; climatological processes; geophysical processes; oceanography; and solid earth.

  18. Geophysical interpretation of U, Th, and rare earth element mineralization of the Bokan Mountain peralkaline granite complex, Prince of Wales Island, southeast Alaska

    USGS Publications Warehouse

    McCafferty, Anne E.; Stoeser, Douglas B.; Van Gosen, Bradley S.

    2014-01-01

    A prospectivity map for rare earth element (REE) mineralization at the Bokan Mountain peralkaline granite complex, Prince of Wales Island, southeastern Alaska, was calculated from high-resolution airborne gamma-ray data. The map displays areas with similar radioelement concentrations as those over the Dotson REE-vein-dike system, which is characterized by moderately high %K, eU, and eTh (%K, percent potassium; eU, equivalent parts per million uranium; and eTh, equivalent parts per million thorium). Gamma-ray concentrations of rocks that share a similar range as those over the Dotson zone are inferred to locate high concentrations of REE-bearing minerals. An approximately 1300-m-long prospective tract corresponds to shallowly exposed locations of the Dotson zone. Prospective areas of REE mineralization also occur in continuous swaths along the outer edge of the pluton, over known but undeveloped REE occurrences, and within discrete regions in the older Paleozoic country rocks. Detailed mineralogical examinations of samples from the Dotson zone provide a means to understand the possible causes of the airborne Th and U anomalies and their relation to REE minerals. Thorium is sited primarily in thorite. Uranium also occurs in thorite and in a complex suite of ±Ti±Nb±Y oxide minerals, which include fergusonite, polycrase, and aeschynite. These oxides, along with Y-silicates, are the chief heavy REE (HREE)-bearing minerals. Hence, the eU anomalies, in particular, may indicate other occurrences of similar HREE-enrichment. Uranium and Th chemistry along the Dotson zone showed elevated U and total REEs east of the Camp Creek fault, which suggested the potential for increased HREEs based on their association with U-oxide minerals. A uranium prospectivity map, based on signatures present over the Ross-Adams mine area, was characterized by extremely high radioelement values. Known uranium deposits were identified in the U-prospectivity map, but the largest tract occurs

  19. Great Lakes Climate and Water Movement. Earth Systems - Education Activities for Great Lakes Schools (ES-EAGLS).

    ERIC Educational Resources Information Center

    Miller, Heidi, Ed.; Sheaffer, Amy L., Ed.

    This activity book is part of a series designed to take a concept or idea from the existing school curriculum and develop it in the context of the Great Lakes using teaching approaches and materials appropriate for students in middle and high school. The theme of this book is Great Lakes climate and water movement. Students learn about land-sea…

  20. Earth Rotation

    NASA Technical Reports Server (NTRS)

    Dickey, Jean O.

    1995-01-01

    The study of the Earth's rotation in space (encompassing Universal Time (UT1), length of day, polar motion, and the phenomena of precession and nutation) addresses the complex nature of Earth orientation changes, the mechanisms of excitation of these changes and their geophysical implications in a broad variety of areas. In the absence of internal sources of energy or interactions with astronomical objects, the Earth would move as a rigid body with its various parts (the crust, mantle, inner and outer cores, atmosphere and oceans) rotating together at a constant fixed rate. In reality, the world is considerably more complicated, as is schematically illustrated. The rotation rate of the Earth's crust is not constant, but exhibits complicated fluctuations in speed amounting to several parts in 10(exp 8) [corresponding to a variation of several milliseconds (ms) in the Length Of the Day (LOD) and about one part in 10(exp 6) in the orientation of the rotation axis relative to the solid Earth's axis of figure (polar motion). These changes occur over a broad spectrum of time scales, ranging from hours to centuries and longer, reflecting the fact that they are produced by a wide variety of geophysical and astronomical processes. Geodetic observations of Earth rotation changes thus provide insights into the geophysical processes illustrated, which are often difficult to obtain by other means. In addition, these measurements are required for engineering purposes. Theoretical studies of Earth rotation variations are based on the application of Euler's dynamical equations to the problem of finding the response of slightly deformable solid Earth to variety of surface and internal stresses.

  1. Pointing losses in single-axis and fixed-mount earth-station antennas due to satellite movement

    NASA Astrophysics Data System (ADS)

    Buchsbaum, L. M.

    1986-06-01

    There are substantial cost advantages in the use of single-axis or fixed-mount earth-station antennas, thus reducing or eliminating the need for autotracking in earth-stations operating with quasi-stationary satellites. Such cost advantages are more relevant in small antennas where the tracking system represents a larger percentage of the overall cost. In addition, small antennas are particularly suitable to be operated without autotracking, owing to their wider half-power beamwidth. This paper describes a model for calculating the antenna pointing loss as a function of the antenna diameter, operating frequency band, satellite station-keeping tolerances, and the relative geometry between the earth-station and the satellite. The model has been extensively used in the development of Intelsat's IBS and VISTA services as well as in domestic leases. Although the model has been developed based on orbital mechanics equations, its emphasis is towards earth-station and systems engineering applications. Some example calculations and results obtained through an HP-41 CV programmable calculator are also provided.

  2. EDITORIAL: The interface between geophysics and engineering

    NASA Astrophysics Data System (ADS)

    2004-03-01

    Journal of Geophysics and Engineering (JGE) aims to publicize and promote research and developments in geophysics and in related areas of engineering. As stated in the journal scope, JGE is positioned to bridge the gap between earth physics and geo-engineering, where it reflects a growing trend in both industry and academia. JGE covers those aspects of engineering that bear closely on geophysics or on the targets and problems that geophysics addresses. Typically this will be engineering focused on the subsurface, particularly petroleum engineering, rock mechanics, geophysical software engineering, drilling technology, remote sensing, instrumentation and sensor design. There is a trend, visible throughout academia, for rapid expansion in cross-disciplinary, multi-disciplinary and inter-disciplinary working. Many of the most important and exciting problems and advances are being made at the boundaries between traditional subject areas and, increasingly, techniques from one discipline are finding applications in others. There is a corresponding increasing requirement for researchers to be aware of developments in adjacent areas and for papers published in one area to be readily accessible, both in terms of location and language, to those in others. One such area that is expanding rapidly is that at the interface between geophysics and engineering. There are three principal developments. Geophysics, and especially applied geophysics, is increasingly constrained by the limits of technology, particularly computing technology. Consequently, major advances in geophysics are often predicated upon major developments in engineering and many research geophysicists are working in multi-disciplinary teams with engineers. Engineering problems relevant to the sub-surface are increasingly looking to advances in geophysics to provide part of the solution. Engineering systems, for example, for tunnel boring or petroleum reservoir management, are using high-resolution geophysical

  3. The 1990 Western Pacific Geophysics meeting

    NASA Technical Reports Server (NTRS)

    1990-01-01

    The 1990 Western Pacific Geophysics Meeting was held in Kanazawa, Japan from 15-21 Aug. 1990. This was the first meeting of a new series of meetings for the American Geophysical Union, and it proved to be very successful in terms of the scientific program and attendance, which included over 1,000 participants. The intent of this meeting was an effort on the part of the American Geophysical Union (AGU) and several Japanese geophysical societies to gather individual Earth and space scientists at a major scientific meeting to focus on geophysical problems being studied in the western Pacific rim. The meeting was organized along the lines of a typical AGU annual meeting with some invited talks, many contributed talks, poster sessions, and with emphasis on presentations and informal discussions. The program committee consisted of scientists from both the U.S. and Japan. This meeting provided ample opportunities for U.S. and Japanese scientists to get to know each other and their works on a one-to-one basis. It was also a valuable opportunity for students studying geophysics to get together and interact with each other and with scientists from both the U.S. and Japan. There were 939 abstracts submitted to the conference and a total of 102 sessions designed as a result of the abstracts received. The topics of interest are as follows: space geodetic and observatory measurements for earthquake and tectonic studies; gravity, sea level, and vertical motion; variations in earth rotation and earth dynamics; sedimentary magnetism; global processes and precipitation; subsurface contaminant transport; U.S. Western Pacific Rim initiatives in hydrology; shelf and coastal circulation; tectonics, magmatism, and hydrothermal processes; earthquake prediction and hazard assessment; seismic wave propagation in realistic media; and dynamics and structure of plate boundaries and of the Earth's deep interior.

  4. How to store and share geophysical data

    NASA Astrophysics Data System (ADS)

    2012-08-01

    The drive for open access to the results of publicly funded research applies, in the case of Earth sciences, to the datasets acquired with centrally supplied equipment. Alex Brisbourne examines how this is made possible for data obtained using NERC's Geophysical Equipment Facility.

  5. Mass Transport in Global Geophysical Fluids

    NASA Technical Reports Server (NTRS)

    Chao, B. F.

    1999-01-01

    Mass transports occurring in the atmosphere-hydrosphere-solid Earth-core system (the "global geophysical fluids") are important geophysical phenomena. They occur on all temporal and spatial scales. Examples include air mass and ocean circulations, tides, hydrological water redistribution, mantle processes such as post-glacial rebound, earthquakes and tectonic motions, and core geodynamo activities. With only a few exceptions on the Earth surface, the temporal history and spatial pattern of such mass transport are often not amenable to direct observations. Space geodesy techniques, however, have the capability of monitoring certain direct consequences of the mass transport, including Earth's rotation variations, gravitational field variations, and the geocenter motion. These techniques include the very-long-baseline interferometry, satellite laser ranging and Doppler tracking, and the Global Positioning System, all entail global observational networks. While considerable advances have been made in observing and understanding of the dynamics of Earth's rotation, only the lowest-degree gravitational variations have been observed and limited knowledge of geocenter motion obtained. New space missions, projects and initiatives promise to further improve the measurements and hence our knowledge about the global mass transports. The latter contributes to our understanding and modeling capability of the geophysical processes that produce and regulate the mass transports, as well as the solid Earth's response to such changes in constraining the modeling of Earth's mechanical properties.

  6. The physics of the earth's core: An introduction

    SciTech Connect

    Melchior, P.

    1986-01-01

    This book is a reference text providing information on physical topics of recent developments in internal geophysics. The text summarizes papers covering theoretical geophysics. Basic formulae, definitions and theorems are not explained in detail due to the limited space. The contents include applications to geodesy, geophysics, astronomy, astrophysics, geophysics and planetary physics. The formal contents include: The Earth's model; Thermodynamics; Hydrodynamics; Geomagnetism; Geophysical implications in the Earth's core.

  7. Fiber optic geophysical sensors

    DOEpatents

    Homuth, Emil F.

    1991-01-01

    A fiber optic geophysical sensor in which laser light is passed through a sensor interferometer in contact with a geophysical event, and a reference interferometer not in contact with the geophysical event but in the same general environment as the sensor interferometer. In one embodiment, a single tunable laser provides the laser light. In another embodiment, separate tunable lasers are used for the sensor and reference interferometers. The invention can find such uses as monitoring for earthquakes, and the weighing of objects.

  8. Monitoring Global Geophysical Fluids by Space Geodesy

    NASA Technical Reports Server (NTRS)

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

    1999-01-01

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

  9. Monitoring Global Geophysical Fluids by Space Geodesy

    NASA Technical Reports Server (NTRS)

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

    1999-01-01

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

  10. Non-Seismic Geophysical Approaches to Monitoring

    SciTech Connect

    Hoversten, G.M.; Gasperikova, Erika

    2004-09-01

    This chapter considers the application of a number of different geophysical techniques for monitoring geologic sequestration of CO2. The relative merits of the seismic, gravity, electromagnetic (EM) and streaming potential (SP) geophysical techniques as monitoring tools are examined. An example of tilt measurements illustrates another potential monitoring technique, although it has not been studied to the extent of other techniques in this chapter. This work does not represent an exhaustive study, but rather demonstrates the capabilities of a number of geophysical techniques on two synthetic modeling scenarios. The first scenario represents combined CO2 enhance oil recovery (EOR) and sequestration in a producing oil field, the Schrader Bluff field on the north slope of Alaska, USA. The second scenario is of a pilot DOE CO2 sequestration experiment scheduled for summer 2004 in the Frio Brine Formation in South Texas, USA. Numerical flow simulations of the CO2 injection process for each case were converted to geophysical models using petrophysical models developed from well log data. These coupled flow simulation geophysical models allow comparrison of the performance of monitoring techniques over time on realistic 3D models by generating simulated responses at different times during the CO2 injection process. These time-lapse measurements are used to produce time-lapse changes in geophysical measurements that can be related to the movement of CO2 within the injection interval.

  11. Earth Science

    NASA Image and Video Library

    1976-01-01

    The LAGEOS I (Laser Geodynamics Satellite) was developed and launched by the Marshall Space Flight Center on May 4, 1976 from Vandenberg Air Force Base, California . The two-foot diameter satellite orbited the Earth from pole to pole and measured the movements of the Earth's surface.

  12. Strategies for joint geophysical survey design

    NASA Astrophysics Data System (ADS)

    Shakas, Alexis; Maurer, Hansruedi

    2015-04-01

    In recent years, the use of multiple geophysical techniques to image the subsurface has become a popular option. Joint inversions of geophysical datasets are based on the assumption that the spatial variations of the different physical subsurface parameters exhibit structural similarities. In this work, we combine the benefits of joint inversions of geophysical datasets with recent innovations in optimized experimental design. These techniques maximize the data information content while minimizing the data acquisition costs. Experimental design has been used in geophysics over the last twenty years, but it has never been attempted to combine various geophysical imaging methods. We combine direct current geoelectrics, magnetotellurics and seismic refraction travel time tomography data to resolve synthetic 1D layered Earth models. An initial model for the subsurface structure can be taken from a priori geological information and an optimal joint geophysical survey can be designed around the initial model. Another typical scenario includes an existing data set from a past survey and a subsequent survey that is planned to optimally complement the existing data. Our results demonstrate that the joint design methodology provides optimized combinations of data sets that include only a few data points. Nevertheless, they allow constraining the subsurface models equally well as data from a densely sampled survey. Furthermore, we examine the dependency of optimized survey design on the a priori model assumptions. Finally, we apply the methodology to geoelectric and seismic field data collected along 2D profiles.

  13. Multiscale geophysical imaging of the critical zone

    USGS Publications Warehouse

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

    2015-01-01

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

  14. Multiscale geophysical imaging of the critical zone

    NASA Astrophysics Data System (ADS)

    Parsekian, A. D.; Singha, K.; Minsley, B. J.; Holbrook, W. S.; Slater, L.

    2015-03-01

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

  15. Geophysical abstracts 164, January-March 1956

    USGS Publications Warehouse

    Rabbitt, Mary C.; Vitaliano, Dorothy B.; Vesselowsky, S.T.; ,

    1956-01-01

    Geophysical Abstracts includes abstracts of technical papers and books on the physics of the solid earth, the application of physical methods and techniques to geologic problems, and geophysical exploration. A new table of contents, alphabetically arranged, has been adapted to show more clearly the material covered.Abstracts are prepared only of material that is believed to be generally available. Ordinarily abstracts are not published of material with limited circulation (such as dissertations, open-file reports, or memoranda) or of papers presented orally at meetings unless summaries of substantial length are published. Abstracts of papers in Japanese and Chinese are based on abstracts or summaries in a western language accompanying the paper.

  16. Geophysical abstracts 166, July-September 1956

    USGS Publications Warehouse

    Rabbitt, Mary C.; Vitaliano, Dorothy B.; Vesselowsky, S.T.; ,

    1956-01-01

    Geophysical Abstracts includes abstracts of technical papers and books on the physics of the solid earth, the application of physical methods and techniques to geologic problems, and geophysical exploration. The table of contents, which is alphabetically arranged, shows the material covered.Abstracts are prepared only of material that is believed to be generally available. Ordinarily abstracts are not published of material with limited circulation (such as dissertations, open-file reports, or memoranda) or of other papers presented orally at meetings unless summaries of substantial length are published. Abstracts of papers in Japanese and Chinese are based on abstracts or summaries in a western language accompanying the paper.

  17. Geophysical abstracts 165, April-June 1956

    USGS Publications Warehouse

    Rabbitt, Mary C.; Vitaliano, Dorothy B.; Vesselowsky, S.T.; ,

    1956-01-01

    Geophysical Abstracts includes abstracts of technical papers and books on the physics of the solid earth, the application of physical methods and techniques to geologic problems, and geophysical exploration. The table of contents, which is alphabetically arranged, shows the material covered.Abstracts are prepared only of material that is believed to be generally available. Ordinarily abstracts are not published of material with limited circulation (such as dissertations, open-file reports, or memoranda) or of other papers presented orally at meetings unless summaries of substantial length are published. Abstracts of papers in Japanese and Chinese are based on abstracts or summaries in a western language accompanying the paper.

  18. Geophysical abstracts 167, October-December 1956

    USGS Publications Warehouse

    Rabbitt, Mary C.; Vitaliano, Dorothy B.; Vesselowsky, S.T.; ,

    1956-01-01

    Geophysical Abstracts includes abstracts of technical papers and books on the physics of the solid earth, the application of physical methods and techniques to geologic problems, and geophysical exploration. The table of contents, which is alphabetically arranged, shows the material covered.Abstracts are prepared only of material that is believed to be generally available. Ordinarily abstracts are not published of material with limited circulation (such as dissertations, open-file reports, or memoranda) or of other papers presented orally at meetings unless summaries of substantial length are published. Abstracts of papers in Japanese and Chinese are based on abstracts or summaries in a western language accompanying the paper.

  19. Earth-Fissure Movements Associated with Fluctuations in Ground-Water Levels near the Picacho Mountains, South-Central Arizona, 1980-84

    USGS Publications Warehouse

    Carpenter, M.C.

    1993-01-01

    The Picacho earth fissure transects subsiding alluvial sediments near the east periphery of the Picacho basin in south-central Arizona. The basin has undergone land subsidence of as much as 3.8 meters since the 1930's owing to compaction of the aquifer system in response to ground-water-Ievel declines that have exceeded 100 meters. The fissure, which extends generally north-south for 15 kilometers, exhibits horizontal tensile failure and as much as 0.6 meter of normal dip-slip movement at the land surface. The west side of the fissure is down thrown. The fissure was observed as early as 1927 and is the longest earth fissure in Arizona. Vertical and horizontal displacements were monitored along a line normal to the fissure. The survey line extends from a bedrock outcrop in the Picacho Mountains on the east, past an observation well near the fissure, to a point 1,422 meters to the west. From May 1980 to May 1984, the downthrown west side of the fissure subsided 167+-1.8 millimeters and moved 18+-1.5 millimeters westward into the basin. Concurrently, the relatively upthrown east side subsided 148+-1.8 millimeters and moved 14+-1.5 millimeters westward. Dislocation modeling of deformation along the survey line near the fissure indicates that dip-slip movement has occurred along a vertical fault surface that extends from the land surface to a depth of about 300 meters. Slip was 9 millimeters from May to December 1980 and also 9 millimeters from March to November 1981. Continuous measurements were made of horizontal movement across the fissure using a buried invar-wire horizontal extensometer, while water-level fluctuations were continuously monitored in four piezometers nested in two observation wells. The range of horizontal movement was 4.620 millimeters, and the range of water-level fluctuation in the nearest piezometer in the deep alluvium was 9.05 meters. The maximum annual opening of the fissure during the study period was 3.740 millimeters from March to October

  20. Geophysics in INSPIRE

    NASA Astrophysics Data System (ADS)

    Sőrés, László

    2013-04-01

    INSPIRE is a European directive to harmonize spatial data in Europe. Its' aim is to establish a transparent, multidisciplinary network of environmental information by using international standards and OGC web services. Spatial data themes defined in the annex of the directive cover 34 domains that are closely bundled to environment and spatial information. According to the INSPIRE roadmap all data providers must setup discovery, viewing and download services and restructure data stores to provide spatial data as defined by the underlying specifications by 2014 December 1. More than 3000 institutions are going to be involved in the progress. During the data specification process geophysics as an inevitable source of geo information was introduced to Annex II Geology. Within the Geology theme Geophysics is divided into core and extended model. The core model contains specifications for legally binding data provisioning and is going to be part of the Implementation Rules of the INSPIRE directives. To minimize the work load of obligatory data transformations the scope of the core model is very limited and simple. It covers the most essential geophysical feature types that are relevant in economic and environmental context. To fully support the use cases identified by the stake holders the extended model was developed. It contains a wide range of spatial object types for geophysical measurements, processed and interpreted results, and wrapper classes to help data providers in using the Observation and Measurements (O&M) standard for geophysical data exchange. Instead of introducing the traditional concept of "geophysical methods" at a high structural level the data model classifies measurements and geophysical models based on their spatial characteristics. Measurements are classified as geophysical station (point), geophysical profile (curve) and geophysical swath (surface). Generic classes for processing results and interpretation models are curve model (1D), surface

  1. Electromagnetic geophysical observation with controlled source

    NASA Astrophysics Data System (ADS)

    Hachay, Olga; Khachay, Oleg

    2016-04-01

    In the paper the new theoretical and methodical approaches are examined for detailed investigations of the structure and state of the geological medium, and its behavior as a dynamic system in reaction to external man-made influences. To solve this problem it is necessary to use geophysical methods that have sufficient resolution and that are built on more complicated models than layered or layered-block models. One of these methods is the electromagnetic induction frequency-geometrical method with controlled sources. Here we consider new approaches using this method for monitoring rock shock media by means of natural experiments and interpretation of the practical results. That method can be used by oil production in mines, where the same events of non stability can occur. The key ideas of twenty first century geophysics from the point of view of geologist academician A.N. Dmitrievskiy [Dmitrievskiy, 2009] are as follows. "The geophysics of the twenty first century is an understanding that the Earth is a self-developing, self-supporting geo-cybernetic system, in which the role of the driving mechanism is played by the field gradients; the evolution of geological processes is a continuous chain of transformations and the interaction of geophysical fields in the litho- hydro- and atmosphere. The use of geophysical principles of a hierarchical quantum of geophysical space, non-linear effects, and the effects of reradiating geophysical fields will allow the creation of a new geophysics. The research, in which earlier only pure geophysical processes and technologies were considered, nowadays tends to include into consideration geophysical-chemical processes and technologies. This transformation will allow us to solve the problems of forecasting geo-objects and geo-processes in previously unavailable geological-technological conditions." The results obtained allow us to make the following conclusions, according to the key ideas of academician A.N. Dmitrievskiy: the rock

  2. The Physics of Heavy Oils: Implications for Recovery and Geophysical Monitoring

    NASA Astrophysics Data System (ADS)

    Schmitt, Douglas

    2007-03-01

    Our capacity to find and produce conventional light petroleum oils are unable to keep pace with the growth in the growing global demand for energy. With the breakpoint between petroleum production and consumption imminent, a good deal of recent efforts have focused on developing the `heavy' hydrocarbon reserves. Such resources include the extensive heavy oil deposits of Venezuela, the bitumen resources of Canada, and even the solid kerogens (oil shale) of the United States. Capital investments, in particular, have been large in Canada's oil sands due in part to the extensive nature of the resource and already in excess of 30% of Canada's production comes from heavier hydrocarbon deposits. The larger input costs associated with such projects, however, requires that the production be monitored more fully; and this necessitates that both the oils and the porous media which hold them be understood. Geophysical `time-lapse' monitoring seeks to better constrain the areal distribution and movements of fluids in the subsurface by examining the changes in a geophysical response such as seismic reflectivity, micro-gravity variations, or electrical conductivity that arise during production. For example, a changed geophysical seismic character directly depends on relies on variations in the longitudinal and transverse wave speeds and attenuation and mass densities of the materials in the earth. These are controlled by a number of extrinsic conditions such as temperature, fluid pressure, confining stress, and fluid phase and saturation state. Understanding the geophysical signature over a given reservoir requires that the behavior of the porous rock physical properties be well understood and a variety of measurements are being made in laboratories. In current practice, the interpretation of the geophysical field responses is assisted by combined modeling of fluid flow and seismic wave fields. The least understood link in this process, however, is the lack of knowledge on rock

  3. Geophysical Institute biennial report 1995--1996

    SciTech Connect

    1998-06-01

    The mission of the Geophysical Institute is to understand the basic physical processes governing Earth, especially as they occur in, or are relevant to the Arctic; to train graduate and undergraduate students to play leading roles in tomorrow`s society; to solve applied geophysical problems and develop resource-oriented technology of importance to the state and the nation; and to satisfy the intellectual and technological needs of fellow Alaskans through public service. The variety of subjects studied by the faculty, research staff members, and graduate students at the Geophysical Institute include auroral physics and chemistry, arctic haze, ice fog, atmospheric dynamics, ozone, Alaska weather patterns, regional meteorology and climatology, global climate change, cloud physics and radiation, permafrost, glaciers, sea ice, remote sensing, geothermal energy, tectonics, volcanoes and earthquakes. Summaries are presented of the projects undertaken by the Institute in these fields.

  4. Fiber optic geophysical sensors

    DOEpatents

    Homuth, E.F.

    1991-03-19

    A fiber optic geophysical sensor is described in which laser light is passed through a sensor interferometer in contact with a geophysical event, and a reference interferometer not in contact with the geophysical event but in the same general environment as the sensor interferometer. In one embodiment, a single tunable laser provides the laser light. In another embodiment, separate tunable lasers are used for the sensor and reference interferometers. The invention can find such uses as monitoring for earthquakes, and the weighing of objects. 2 figures.

  5. High temperature geophysical instrumentation

    SciTech Connect

    Hardee, H.C.

    1988-06-01

    The instrumentation development program was to proceed in parallel with scientific research and was driven by the needs of researchers. The development of these instruments has therefore included numerous geophysical field tests, many of which have resulted in the publication of scientific articles. This paper is a brief summary of some of the major geophysical instruments that have been developed and tested under the High Temperature Geophysics Program. These instruments are briefly described and references are given for further detailed information and for scientific papers that have resulted from the use of these instruments. 9 refs., 14 figs.

  6. Earth and ocean modeling

    NASA Technical Reports Server (NTRS)

    Knezovich, F. M.

    1976-01-01

    A modular structured system of computer programs is presented utilizing earth and ocean dynamical data keyed to finitely defined parameters. The model is an assemblage of mathematical algorithms with an inherent capability of maturation with progressive improvements in observational data frequencies, accuracies and scopes. The Eom in its present state is a first-order approach to a geophysical model of the earth's dynamics.

  7. Geophysical Models for Nuclear Explosion Monitoring

    SciTech Connect

    Pasyanos, M E; Walter, W R; Flanagan, M

    2003-07-16

    Geophysical models are increasingly recognized as an important component of regional calibrations for seismic monitoring. The models can be used to predict geophysical measurements, such as body wave travel times, and can be derived from direct regional studies or even by geophysical analogy. While empirical measurements of these geophysical parameters might be preferred, in aseismic regions or regions without seismic stations, this data might not exist. In these cases, models represent a 'best guess' of the seismic properties in a region, which improves on global models such as the PREM (Preliminary Reference Earth Model) or the IASPEI (International Association of Seismology and Physics of the Earth's Interior) models. The model-based predictions can also serve as a useful background for the empirical measurements by removing trends in the data. To this end, Lawrence Livermore National Laboratory (LLNL) has developed the WENA model for Western Eurasia and North Africa. This model is constructed using a regionalization of several dozen lithospheric (crust and uppermost mantle) models, combined with the Laske sediment model and 3SMAC upper mantle. We have evaluated this model using a number of data sets, including travel times, surface waves, receiver functions, and waveform analysis. Similarly, Los Alamos National Laboratory (LANL) has developed a geophysical model for East Asia, allowing LLNL/LANL to construct a model for all of Eurasia and North Africa. These models continue to evolve as new and updated datasets are used to critically assess the predictive powers of the model. Research results from this meeting and other reports and papers can be used to update and refine the regional boundaries and regional models. A number of other groups involved in monitoring have also developed geophysical models. As these become available, we will be assessing the models and their constitutive components for their suitability for inclusion in the National Nuclear Security

  8. Global Change Geodesy: A Geophysical Perspective

    NASA Astrophysics Data System (ADS)

    Mitrovica, J. X.

    2014-12-01

    It is a truism that as the precision of geodetic measurement techniques improves, the accuracy of the geophysical modeling of processes that contribute to the observations must keep pace. Studies of the Earth's response to human-induced climate change provide many notable, and pressing, illustrations of this axiom. For example, estimates of recent ice volume changes, as inferred from satellite gravity measurements, tide gauge and satellite-altimetry records of sea level changes, or astronomical and space-geodetic constraints on Earth rotation, require improved theoretical and numerical treatments of ongoing glacial isostatic adjustment in response to the last ice age. However, the interplay between geodesy and geophysics is not a one-way street; geophysical modeling has emphasized, for example, that the geographic variability in sea level measurements - once considered a nuisance in efforts to infer long term trends - provides a powerful constraint on both the individual sources of meltwater and their sum. In this talk, I will discuss a series of case studies that demonstrate how interdisciplinary research at the interface between geodesy and geophysics has recently resolved several outstanding problems in global change research, including Walter Munk's enigma of global sea-level rise and the apparent failure to close the budget of twentieth century sea level. Moreover, in the same interdisciplinary context, I will highlight uncertainties that currently limit our understanding of polar ice sheet stability in a progressively warming world.

  9. Phillips Laboratory Geophysics Scholar Program

    DTIC Science & Technology

    1993-09-30

    research at Phillips Laboratory . Research sponsored by Air Force Geophysics Laboratory ...Geophysics Laboratory (now the Phillips Laboratory , Geophysics Directorate), United States Air Force for its sponsorship of this research through the Air ...September 1993 Approved for public release; distribution unlimited PHILLIPS LABORATORY Directorate of Geophysics AIR FORCE MATERIEL COMMAND

  10. Geophysical and Atmospheric Evolution of Habitable Planets

    NASA Astrophysics Data System (ADS)

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

    2010-01-01

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

  11. Geophysical and atmospheric evolution of habitable planets.

    PubMed

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

    2010-01-01

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

  12. Open Access to Geophysical Data

    NASA Astrophysics Data System (ADS)

    Sergeyeva, Nataliya A.; Zabarinskaya, Ludmila P.

    2017-04-01

    Russian World Data Centers for Solar-Terrestrial Physics & Solid Earth Physics hosted by the Geophysical Center of the Russian Academy of Sciences are the Regular Members of the ICSU-World Data System. Guided by the principles of the WDS Constitution and WDS Data Sharing Principles, the WDCs provide full and open access to data, long-term data stewardship, compliance with agreed-upon data standards and conventions, and mechanisms to facilitate and improve access to data. Historical and current geophysical data on different media, in the form of digital data sets, analog records, collections of maps, descriptions are stored and collected in the Centers. The WDCs regularly fill up repositories and database with new data, support them up to date. Now the WDCs focus on four new projects, aimed at increase of data available in network by retrospective data collection and digital preservation of data; creation of a modern system of registration and publication of data with digital object identifier (DOI) assignment, and promotion of data citation culture; creation of databases instead of file system for more convenient access to data; participation in the WDS Metadata Catalogue and Data Portal by creating of metadata for information resources of WDCs.

  13. Symmetries in geology and geophysics.

    PubMed

    Turcotte, D L; Newman, W I

    1996-12-10

    Symmetries have played an important role in a variety of problems in geology and geophysics. A large fraction of studies in mineralogy are devoted to the symmetry properties of crystals. In this paper, however, the emphasis will be on scale-invariant (fractal) symmetries. The earth's topography is an example of both statistically self-similar and self-affine fractals. Landforms are also associated with drainage networks, which are statistical fractal trees. A universal feature of drainage networks and other growth networks is side branching. Deterministic space-filling networks with side-branching symmetries are illustrated. It is shown that naturally occurring drainage networks have symmetries similar to diffusion-limited aggregation clusters.

  14. Strainmeters and tiltmeters in geophysics

    NASA Technical Reports Server (NTRS)

    Goulty, N. R.

    1976-01-01

    Several types of sensitive strainmeters and tiltmeters have been developed, and it is now becoming clear which geophysical applications are most suitable for these instruments. In general, strainmeters and tiltmeters are used for observing ground deformation at periods of minutes to days. Small-scale lateral inhomogeneities at the instrument sites distort signals by a few percent, although the effects of large structures can be calculated. In earth tide work these lateral inhomogeneities and unknown ocean loading signals prevent accurate values of the regional tide from being obtained. This limits tidal investigations to looking for temporal variations, possibly associated with pre-earthquake dilatancy, and spatial variations caused by gross elasticity contrasts in the local geological structure. Strainmeters and tiltmeters are well suited for observing long-period seismic waves, seismic slip events on faults and volcano tumescence, where small site-induced distortions in the measured signals are seldom important.

  15. Fractals in geology and geophysics

    NASA Technical Reports Server (NTRS)

    Turcotte, Donald L.

    1989-01-01

    The definition of a fractal distribution is that the number of objects N with a characteristic size greater than r scales with the relation N of about r exp -D. The frequency-size distributions for islands, earthquakes, fragments, ore deposits, and oil fields often satisfy this relation. This application illustrates a fundamental aspect of fractal distributions, scale invariance. The requirement of an object to define a scale in photograhs of many geological features is one indication of the wide applicability of scale invariance to geological problems; scale invariance can lead to fractal clustering. Geophysical spectra can also be related to fractals; these are self-affine fractals rather than self-similar fractals. Examples include the earth's topography and geoid.

  16. Fractals in geology and geophysics

    NASA Technical Reports Server (NTRS)

    Turcotte, Donald L.

    1989-01-01

    The definition of a fractal distribution is that the number of objects N with a characteristic size greater than r scales with the relation N of about r exp -D. The frequency-size distributions for islands, earthquakes, fragments, ore deposits, and oil fields often satisfy this relation. This application illustrates a fundamental aspect of fractal distributions, scale invariance. The requirement of an object to define a scale in photograhs of many geological features is one indication of the wide applicability of scale invariance to geological problems; scale invariance can lead to fractal clustering. Geophysical spectra can also be related to fractals; these are self-affine fractals rather than self-similar fractals. Examples include the earth's topography and geoid.

  17. Identification and Description of Geophysical Techniques.

    DTIC Science & Technology

    1980-11-01

    for reaction with groundwater and pollutants. Shales and clays, for example, have the po- tential for concentrating certain ions by the processes of...8217tured shale unit. Geophysical expression of lithology can include acoustic velocity, electrical resistivity, spontaneous potential, density, gamma...the travel time required for acoustic compressional waves, generated in the earth by a near-surface explosion, mechanical impact, or vibration , to

  18. Geophysics: ancient air, ozone, and faults.

    PubMed

    Kerr, R A

    1988-01-08

    Researchers who gathered in San Francisco in December at the annual fall meeting of the American Geophysical Union heard the usual variety of talks treating everything from Earth's core to the tenuous wisps of solar particles far beyond Pluto. Earthquakes, the local California variety in particular, figured prominently, as did the currently popular subjects of ancient air trapped in amber and the deepening Antarctic ozone hole.

  19. Global Geophysical Fluids Center of IERS

    NASA Technical Reports Server (NTRS)

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

    2000-01-01

    The Global Geophysical Fluids Center (GGFC) and its seven Special Bureaus (SB, for Atmosphere, Oceans, Tides, Hydrology, Mantle, Core and Gravity/Geocenter) were establishes by the International Earth Rotation Service in 1998, to support global geodynamic research. Mass transports in the geophysical fluids of the Earth system will cause observable geodynamic effects on a broad time scale.These include (1) variations in the solid Earth's rotation (in length-of-day and polar motion/nutation) via the conservation of angular momentum and effected by torques at the fluid-solid Earth interface; (2) changes in the global gravitational field according to Newton's gravitational law; and (3) motion in the center of mass of the solid Earth relative to that of the whole Earth ("geocenter") via the conservation of linear momentum. These minute signals have become observable by space geodetic techniques, primarily VLBI, SLR, GPS, and DORIS, and new exciting data will be available by space gravity, altimetry, SAR, and magnetic missions. In this sense the precise space geodetic techniques have become effective means of remote sensing of global mass transports. The GGFC and its SBs have the responsibility of supporting, facilitating, and providing services to the worldwide research community in the related research areas. We compute, analyze, compare, archive, and disseminate the time series of the angular momenta and the related torques, gravitational coefficients, and geocenter shift for all geophysical fluids, based on global observational data, and/or products from state-of-the-art models some of which assimilate such data. The computed quantities, algorithm and data formats are standardized. This paper reviews our activities, reports the status, and looks forward into the future.

  20. Global Geophysical Fluids Center of IERS

    NASA Technical Reports Server (NTRS)

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

    2000-01-01

    The Global Geophysical Fluids Center (GGFC) and its seven Special Bureaus (SB, for Atmosphere, Oceans, Tides, Hydrology, Mantle, Core and Gravity/Geocenter) were establishes by the International Earth Rotation Service in 1998, to support global geodynamic research. Mass transports in the geophysical fluids of the Earth system will cause observable geodynamic effects on a broad time scale.These include (1) variations in the solid Earth's rotation (in length-of-day and polar motion/nutation) via the conservation of angular momentum and effected by torques at the fluid-solid Earth interface; (2) changes in the global gravitational field according to Newton's gravitational law; and (3) motion in the center of mass of the solid Earth relative to that of the whole Earth ("geocenter") via the conservation of linear momentum. These minute signals have become observable by space geodetic techniques, primarily VLBI, SLR, GPS, and DORIS, and new exciting data will be available by space gravity, altimetry, SAR, and magnetic missions. In this sense the precise space geodetic techniques have become effective means of remote sensing of global mass transports. The GGFC and its SBs have the responsibility of supporting, facilitating, and providing services to the worldwide research community in the related research areas. We compute, analyze, compare, archive, and disseminate the time series of the angular momenta and the related torques, gravitational coefficients, and geocenter shift for all geophysical fluids, based on global observational data, and/or products from state-of-the-art models some of which assimilate such data. The computed quantities, algorithm and data formats are standardized. This paper reviews our activities, reports the status, and looks forward into the future.

  1. Looking into the Earth

    NASA Astrophysics Data System (ADS)

    Mussett, Alan E.; Aftab Khan, M.; Button, Illustrated By Sue

    2000-12-01

    Looking Into the Earth comprehensively describes the principles and applications of both `global' and `exploration' geophysics on all scales. It forms an introduction to geophysics suitable for those who do not necessarily intend to become professional geophysicists, including geologists, civil engineers, environmental scientists, and field archaeologists. The book is organised into two parts: Part 1 describes the geophysical methods, while Part 2 illustrates their use in a number of extended case histories. Mathematical and physical principles are introduced at an elementary level, and then developed as necessary. Student questions and exercises are included at the end of each chapter. The book is aimed primarily at introductory and intermediate university students taking courses in geology, earth science, environmental science, and engineering. It will also form an excellent introductory textbook in geophysics departments, and will help practising geologists, archaeologists and engineers understand what geophysics can offer their work. Accessible to students with little background in maths and physics Covers both global and applied geophysics Well illustrated and contains many student exercises and case studies Written by experienced teachers of geophysics

  2. Earth materials and earth dynamics

    SciTech Connect

    Bennett, K; Shankland, T.

    2000-11-01

    In the project ''Earth Materials and Earth Dynamics'' we linked fundamental and exploratory, experimental, theoretical, and computational research programs to shed light on the current and past states of the dynamic Earth. Our objective was to combine different geological, geochemical, geophysical, and materials science analyses with numerical techniques to illuminate active processes in the Earth. These processes include fluid-rock interactions that form and modify the lithosphere, non-linear wave attenuations in rocks that drive plate tectonics and perturb the earth's surface, dynamic recrystallization of olivine that deforms the upper mantle, development of texture in high-pressure olivine polymorphs that create anisotropic velocity regions in the convecting upper mantle and transition zone, and the intense chemical reactions between the mantle and core. We measured physical properties such as texture and nonlinear elasticity, equation of states at simultaneous pressures and temperatures, magnetic spins and bonding, chemical permeability, and thermal-chemical feedback to better characterize earth materials. We artificially generated seismic waves, numerically modeled fluid flow and transport in rock systems and modified polycrystal plasticity theory to interpret measured physical properties and integrate them into our understanding of the Earth. This is the final report of a three-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL).

  3. Surface exploration geophysics applied to the moon

    SciTech Connect

    Ander, M.E.

    1984-01-01

    With the advent of a permanent lunar base, the desire to explore the lunar near-surface for both scientific and economic purposes will arise. Applications of exploration geophysical methods to the earth's subsurface are highly developed. This paper briefly addresses some aspects of applying this technology to near surface lunar exploration. It is noted that both the manner of application of some techniques, as well as their traditional hierarchy as assigned on earth, should be altered for lunar exploration. In particular, electromagnetic techniques may replace seismic techniques as the primary tool for evaluating near-surface structure.

  4. Magnetic field of the Earth

    NASA Astrophysics Data System (ADS)

    Popov, Aleksey

    2013-04-01

    The magnetic field of the Earth has global meaning for a life on the Earth. The world geophysical science explains: - occurrence of a magnetic field of the Earth it is transformation of kinetic energy of movements of the fused iron in the liquid core of Earth - into the magnetic energy; - the warming up of a kernel of the Earth occurs due to radioactive disintegration of elements, with excretion of thermal energy. The world science does not define the reasons: - drift of a magnetic dipole on 0,2 a year to the West; - drift of lithospheric slabs and continents. The author offers: an alternative variant existing in a world science the theories "Geodynamo" - it is the theory « the Magnetic field of the Earth », created on the basis of physical laws. Education of a magnetic field of the Earth occurs at moving the electric charge located in a liquid kernel, at rotation of the Earth. At calculation of a magnetic field is used law the Bio Savara for a ring electric current: dB = . Magnetic induction in a kernel of the Earth: B = 2,58 Gs. According to the law of electromagnetic induction the Faradey, rotation of a iron kernel of the Earth in magnetic field causes occurrence of an electric field Emf which moves electrons from the center of a kernel towards the mantle. So of arise the radial electric currents. The magnetic field amplifies the iron of mantle and a kernel of the Earth. As a result of action of a radial electric field the electrons will flow from the center of a kernel in a layer of an electric charge. The central part of a kernel represents the field with a positive electric charge, which creates inverse magnetic field Binv and Emfinv When ?mfinv = ?mf ; ?inv = B, there will be an inversion a magnetic field of the Earth. It is a fact: drift of a magnetic dipole of the Earth in the western direction approximately 0,2 longitude, into a year. Radial electric currents a actions with the basic magnetic field of a Earth - it turn a kernel. It coincides with laws

  5. Geophysical Methods: an Overview

    NASA Technical Reports Server (NTRS)

    Becker, A.; Goldstein, N. E.; Lee, K. H.; Majer, E. L.; Morrison, H. F.; Myer, L.

    1992-01-01

    Geophysics is expected to have a major role in lunar resource assessment when manned systems return to the Moon. Geophysical measurements made from a lunar rover will contribute to a number of key studies: estimating regolith thickness, detection of possible large-diameter lava tubes within maria basalts, detection of possible subsurface ice in polar regions, detection of conductive minerals that formed directly from a melt (orthomagmatic sulfides of Cu, Ni, Co), and mapping lunar geology beneath the regolith. The techniques that can be used are dictated both by objectives and by our abilities to adapt current technology to lunar conditions. Instrument size, weight, power requirements, and freedom from orientation errors are factors we have considered. Among the geophysical methods we believe to be appropriate for a lunar resource assessment are magnetics, including gradiometry, time-domain magnetic induction, ground-penetrating radar, seismic reflection, and gravimetry.

  6. Quantitative Geophysics and Geology

    NASA Astrophysics Data System (ADS)

    Wilson, Clark R.

    Most college instructors of geophysics are on the lookout for new textbooks. This is especially the case for instructors of survey courses at the upper division or graduate level, where choices are limited and opinions differ as to what ought be included and the level of detail. As one of those instructors, I was eager to review Quantitative Geophysics and Geology. Its title seemed to fit several courses taught at my institution. But upon reading the book, I found it was not useful for most of our courses.The variety of geophysical topics is so vast that an orderly exposition simply is not possible for all. The book's strong point is that a number of chapters provide succinct and readable reviews of traditional topics, which makes it well suited for an introduction or review at the graduate level.

  7. Geophysical methods: an overview

    NASA Astrophysics Data System (ADS)

    Becker, A.; Goldstein, N. E.; Lee, K. H.; Majer, E. L.; Morrison, H. F.; Myer, L.

    Geophysics is expected to have a major role in lunar resource assessment when manned systems return to the Moon. Geophysical measurements made from a lunar rover will contribute to a number of key studies: estimating regolith thickness, detection of possible large-diameter lava tubes within maria basalts, detection of possible subsurface ice in polar regions, detection of conductive minerals that formed directly from a melt (orthomagmatic sulfides of Cu, Ni, Co), and mapping lunar geology beneath the regolith. The techniques that can be used are dictated both by objectives and by our abilities to adapt current technology to lunar conditions. Instrument size, weight, power requirements, and freedom from orientation errors are factors we have considered. Among the geophysical methods we believe to be appropriate for a lunar resource assessment are magnetics, including gradiometry, time-domain magnetic induction, ground-penetrating radar, seismic reflection, and gravimetry.

  8. Alterant geophysical tomography

    SciTech Connect

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

    1983-05-01

    We describe and evaluate a new geophysical technique used to remotely map fractures between boreholes: alterant geophysical tomography (AGT). The method requires that the attenuation properties of rock fractures be altered by forcing into the rock a fluid with different electrical properties than those of the native fluids in the rock. Measurements of electromagnetic attenuation factor are performed before and after the tracer is used. Measuring changes in attenuation properties offers significant advantages over measuring absolute attentuation properties. Results of an experiment in which this technique was employed are discussed. 4 references, 4 figures.

  9. Geophysics adds a dimension

    SciTech Connect

    Savage, D.

    1984-03-01

    Geophysics is adding technology which can pinpoint drill sites, quicken drilling schedules and enhance success ratios. The use of 3-D seismic surveys can help determine the exact extent and shape of an oil or gas field. Vertical seismic profiling (VSP) also is proving to be extremely useful among companies that recognize its potential. A land air gun has started to refine the seismic surveys since it can be refired on 6 to 8 second intervals. A combination of these geophysical techniques may become a cheaper and more effective way of correlating strata.

  10. Teaching oriented geophysical software

    NASA Astrophysics Data System (ADS)

    Pinto, Victor; Rivero, Lluis; Casas, Albert

    2000-08-01

    Interactive teaching techniques encourage students to adopt an active role in their education and should therefore be used at different levels of the teaching sequence. In order to mitigate the lack of educational software for Applied Geophysics, a fully interactive graphic software has been developed. The program is written in Visual Basic with some subroutines in FORTRAN and is designed for IBM-PC microcomputers using a Windows environment. The program offers the majority of the processes involved in geophysical data handling, modelling, tutorials, and instrument simulators.

  11. Geophysical Fiber Interferometer Gyroscope.

    DTIC Science & Technology

    1979-12-31

    gravitational antenna. Basically, their device was a Twyman -Green laser interferometer that was allegedly well-isolated from its thermal and...r ~AD-AO92 913 UTAH UNIV RESEARCH INST SALT LAKE CITY GEOSPACE SCIE-EYC F/B 20/6 GEOPHYSICAL FIBER INTERFEROMETER GYROSCOPE(U) .S DEC 79 L 0 WEAVER...ACCESSION no: S, 111CIPIENT’S CATALOG NUMBER AF6ii M_ __ _ __I_ _ 4. TItLIL (eovm4jk"IU .TYEo nPaTawn.ocoet GEOPHYSICAL FIBER INTERFEROMETER GYROSCOPE. / 9

  12. Fundamentals of Geophysical Fluid Dynamics

    NASA Astrophysics Data System (ADS)

    McWilliams, James C.

    2006-07-01

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

  13. Geophysics News 1990

    NASA Astrophysics Data System (ADS)

    Cole, Stephen

    The last two years have witnessed many major geophysical events such as the Loma Prieta earthquake, new insights into plate motions, new seismic and mid-ocean ridge observational programs, and new views of a distant planet. AGU's Public Information Committee, chaired by Debra Knopman of the U.S. Geological Survey, was asked by the American Institute of Physics to prepare a series of articles on the major topics in geophysics for publication in Physics News in 1990. Several of those papers did appear in the AIP publication. In the absence of a comparable publication devoted solely to a summary of news in geophysics, AGU is publishing the 20 articles solicited by the Public Information Committee as a booklet, Geophysics News 1990, that is being distributed to the media. The articles are also being published in Eos starting with this issue and continuing for the next several weeks. The topics covered in these articles range from the world's deepest rocks to the powerful blast waves from major solar flares.

  14. Geophysical Signal Recognition,

    DTIC Science & Technology

    1981-01-01

    quite helpful in the magnetosphere. Detecting a particular in earthquake prediction . However pattern recog- micropulsation event can provide a diagnosis...bio- In su..a.iry, application of pattern recognition to medical signals, progress in geophysical signal earthquake prediction is in its infancy

  15. Geophysical limits to global wind power

    NASA Astrophysics Data System (ADS)

    Marvel, Kate; Kravitz, Ben; Caldeira, Ken

    2013-02-01

    There is enough power in Earth's winds to be a primary source of near-zero-emission electric power as the global economy continues to grow through the twenty-first century. Historically, wind turbines are placed on Earth's surface, but high-altitude winds are usually steadier and faster than near-surface winds, resulting in higher average power densities. Here, we use a climate model to estimate the amount of power that can be extracted from both surface and high-altitude winds, considering only geophysical limits. We find wind turbines placed on Earth's surface could extract kinetic energy at a rate of at least 400TW, whereas high-altitude wind power could extract more than 1,800TW. At these high rates of extraction, there are pronounced climatic consequences. However, we find that at the level of present global primary power demand (~ 18TW ref. ), uniformly distributed wind turbines are unlikely to substantially affect the Earth's climate. It is likely that wind power growth will be limited by economic or environmental factors, not global geophysical limits.

  16. Online Polar Oceans Geophysical Databases

    NASA Astrophysics Data System (ADS)

    Goodwillie, A. M.; O'Hara, S.; Arko, R. A.; Carbotte, S. M.

    2006-12-01

    With funding from the Office of Polar Programs of the U.S. National Science Foundation, the Antarctic Multibeam Bathymetry Synthesis (AMBS, http://www.marine-geo.org/antarctic/) is an integrated web-accessible bathymetry and geophysical database for the Southern Ocean and Antarctica, serving data from the US research vessels Nathaniel B. Palmer and Laurence M. Gould, amongst others. Interdisciplinary polar data can be downloaded for free through Data Link (http://www.marine-geo.org/link/index.php) which enables keyword searches by data and instrument type, geographical bounds, scientist, expedition name and dates. The data visualisation tool GeoMapApp (http://www.marine-geo.org/geomapapp/) supports dynamic exploration of a multi-resolutional digital elevation model (DEM) of the global oceans, including the polar regions, allowing users to generate custom grids and maps and import their own data sets and grids. A specialised polar stereographic map projection incorporating multibeam swath bathymetry and the BEDMAP under-ice seaflooor topography is available for the Southern Ocean. To promote inter-operability, we are working with research partners including the Marine Metadata Interoperability (MMI) project and the National Geophysical Data Center to develop standardised metadata and best practices that comply with existing FGDC and ISO standards. For example, the global DEM is served freely as an OGC-compliant Web Map Service map layer and is available for viewing with Google Earth. We are working towards full indexing of the AMBS database holdings at the Antarctic Master Directory. geo.org/antarctic/

  17. Ninety Years of International Cooperation in Geophysics

    NASA Astrophysics Data System (ADS)

    Ismail-Zadeh, A.; Beer, T.

    2009-05-01

    Because applicable physical, chemical, and mathematical studies of the Earth system must be both interdisciplinary and international, the International Union of Geodesy and Geophysics (IUGG) was formed in 1919 as an non-governmental, non-profit organization dedicated to advancing, promoting, and communicating knowledge of the Earth system, its space environment, and the dynamical processes causing change. The Union brings together eight International Associations that address different disciplines of Earth sciences. Through these Associations, IUGG promotes and enables studies in the geosciences by providing a framework for collaborative research and information exchange, by organizing international scientific assemblies worldwide, and via research publications. Resolutions passed by assemblies of IUGG and its International Associations set geophysical standards and promote issues of science policy on which national members agree. IUGG has initiated and/or vigorously supported collaborative international efforts that have led to highly productive worldwide interdisciplinary research programs, such as the International Geophysical Year and subsequent International Years (IPY, IYPE, eGY, and IHY), International Lithosphere Programme, World Climate Research Programme, Geosphere-Biosphere Programme, and Integrated Research on Risk Disaster. IUGG is inherently involved in the projects and programs related to climate change, global warming, and related environmental impacts. One major contribution has been the creation, through the International Council for Science (ICSU), of the World Data Centers and the Federation of Astronomical and Geophysical Data Analysis Services. These are being transformed to the ICSU World Data System, from which the data gathered during the major programs and data products will be available to researchers everywhere. IUGG cooperates with UNESCO, WMO, and some other U.N. and non-governmental organizations in the study of natural catastrophes

  18. Information Theory and the Earth's Density Distribution

    NASA Technical Reports Server (NTRS)

    Rubincam, D. P.

    1979-01-01

    An argument for using the information theory approach as an inference technique in solid earth geophysics. A spherically symmetric density distribution is derived as an example of the method. A simple model of the earth plus knowledge of its mass and moment of inertia lead to a density distribution which was surprisingly close to the optimum distribution. Future directions for the information theory approach in solid earth geophysics as well as its strengths and weaknesses are discussed.

  19. Information theory and the earth's density distribution

    NASA Technical Reports Server (NTRS)

    Rubincam, D. P.

    1978-01-01

    The present paper argues for using the information theory approach as an inference technique in solid earth geophysics. A spherically symmetric density distribution is derived as an example of the method. A simple model of the earth plus knowledge of its mass and moment of inertia leads to a density distribution. Future directions for the information theory approach in solid earth geophysics as well as its strengths and weaknesses are discussed.

  20. Geophysical investigations in Jordan

    USGS Publications Warehouse

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

    1990-01-01

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

  1. Asteroid Surface Geophysics

    NASA Astrophysics Data System (ADS)

    Murdoch, N.; Sánchez, P.; Schwartz, S. R.; Miyamoto, H.

    The regolith-covered surfaces of asteroids preserve records of geophysical processes that have occurred both at their surfaces and sometimes also in their interiors. As a result of the unique microgravity environment that these bodies possess, a complex and varied geophysics has given birth to fascinating features that we are just now beginning to understand. The processes that formed such features were first hypothesized through detailed spacecraft observations and have been further studied using theoretical, numerical, and experimental methods that often combine several scientific disciplines. These multiple approaches are now merging toward a further understanding of the geophysical states of the surfaces of asteroids. In this chapter we provide a concise summary of what the scientific community has learned so far about the surfaces of these small planetary bodies and the processes that have shaped them. We also discuss the state of the art in terms of experimental techniques and numerical simulations that are currently being used to investigate regolith processes occurring on small-body surfaces and that are contributing to the interpretation of observations and the design of future space missions.

  2. Future Chances and Challenges for Near Surface Geophysics

    NASA Astrophysics Data System (ADS)

    Noell, U.; Meyer, U.

    2011-12-01

    Near surface geophysics provides information from global to local scale: a) Standardized geophysical observations are utilized e.g. in risk management frameworks beyond the national level a) Specific tasks in local or regional frameworks as mine flooding or ground water recharge monitoring are required. Either way, near surface geophysics is connected more than ever to technical problems and thus is vastly adopted by engineering. This is a chance and challenge at the same time. The chance is to make near surface geophysics more useful in applied and practical issues, the challenge is to develop new profiles and research directions. Recent satellite earth observation missions have much enhanced capabilities to observe near surface features and changes but generally very limited penetration. Near surface geophysics can bridge the gap between surface characterization and subsurface structures. Subsurface structures as aquifer systems, layering, deposits and mineralization can be determined by non-invasive near surface geophysics. A special challenge here is the enhanced interpretation of the physical data combined with an improved understanding of complex subsurface processes. Moreover, the limits of the interpretation and the measurements need to be quantified. Another future challenge is to gain a better and reliable understanding of soil - water cycles and gaseous flows via near surface geophysics. New methods and techniques that did not seem feasible in the past must reviewed whilst technology developed. This includes squids for magnetics and electromagnetics applications, nuclear magnetic resonance methods etc.

  3. Common interests bind AGU and geophysical groups around the globe

    NASA Astrophysics Data System (ADS)

    McEntee, Christine

    2012-02-01

    In continuation of our work to strengthen alliances with key organizations in the Earth and space science community, AGU president Michael McPhaden, president-elect Carol Finn, and I held a series of meetings with leaders from other science societies during the 2011 Fall Meeting. Over the course of 2 days we met with leaders from the Geophysical Society of America, European Geosciences Union, Japan Geosciences Union, Ethiopian Geophysical Union, Asia Oceania Geosciences Society, Chinese Geophysical Society, and Asociación Latinoamericana de Geofísica Espacial. This gave us a valued opportunity to discuss the common interests and challenges we all face and to learn from each other's experience. The meetings allowed AGU to strengthen existing cooperative agreements and reach new levels of understanding between us and other societies. Additionally, we met with representatives from the Korean Ocean Research and Development Institute to discuss their intention to establish a geophysical union modeled after AGU.

  4. The next generation geophysical investigation of the moon

    NASA Technical Reports Server (NTRS)

    Hood, L. L.; Sonett, C. P.; Rusell, C. T.

    1985-01-01

    Planetary geophysics has mainly the objective to determine the structure, composition, and state of a given body and the relationship between internal processes and surface tectonic features. The moon represents an obvious initial case for application of geophysical techniques to bodies other than the earth. As a result of the Apollo program and associated scientific investigations, some initial progress was made toward geophysical exploration of the moon. The obtained results are briefly discussed, and some major unresolved issues are pointed out. The present status of lunar geophysical data sets is evaluated, taking into account the issues cited and the extent to which future orbital surveys and surface measurements may resolve the remaining problems. Attention is given to seismic data, electromagnetic sounding data, heat-flow data, gravity/topography data, and paleomagnetic data.

  5. COUPLED GEOPHYSICAL-HYDROLOGICAL MODELING OF A CONTROLLED NAPL SPILL

    EPA Science Inventory

    Past studies have shown reasonable sensitivity of geophysical data for detecting or monitoring the movement of non-aqueous phase liquids (NAPLs) in the subsurface. However, heterogeneity in subsurface properties and in NAPL distribution commonly results in non-unique data

    ...

  6. COUPLED GEOPHYSICAL-HYDROLOGICAL MODELING OF A CONTROLLED NAPL SPILL

    EPA Science Inventory

    Past studies have shown reasonable sensitivity of geophysical data for detecting or monitoring the movement of non-aqueous phase liquids (NAPLs) in the subsurface. However, heterogeneity in subsurface properties and in NAPL distribution commonly results in non-unique data

    ...

  7. Distinct Element modeling of geophysical signatures during sinkhole collapse

    NASA Astrophysics Data System (ADS)

    Al-Halbouni, Djamil; Holohan, Eoghan P.; Taheri, Abbas; Dahm, Torsten

    2017-04-01

    A sinkhole forms due to the collapse of rocks or soil near the Earth's surface into an underground cavity. Such cavities represent large secondary pore spaces derived by dissolution and subrosion in the underground. By changing the stress field in the surrounding material, the growth of cavities can lead to a positive feedback, in which expansion and mechanical instability in the surrounding material increases or generates new secondary pore space (e.g. by fracturing), which in turn increases the cavity size, etc. A sinkhole forms due to the eventual subsidence or collapse of the overburden that becomes destabilized and fails all the way to the Earth's surface. Both natural processes like (sub)surface water movement and earthquakes, and human activities, such as mining, construction and groundwater extraction, intensify such feedbacks. The development of models for the mechanical interaction of a growing cavity and fracturing of its surrounding material, thus capturing related precursory geophysical signatures, has been limited, however. Here we report on the advances of a general, simplified approach to simulating cavity growth and sinkhole formation by using 2D Distinct Element Modeling (DEM) PFC5.0 software and thereby constraining pre-, syn- and post-collapse geophysical and geodetic signatures. This physically realistic approach allows for spontaneous cavity development and dislocation of rock mass to be simulated by bonded particle formulation of DEM. First, we present calibration and validation of our model. Surface subsidence above an instantaneously excavated circular cavity is tracked and compared with an incrementally increasing dissolution zone both for purely elastic and non-elastic material.This validation is important for the optimal choice of model dimensions and particles size with respect to simulation time. Second, a cavity growth approach is presented and compared to a well-documented case study, the deliberately intensified sinkhole collapse at

  8. Large natural geophysical events: planetary planning

    SciTech Connect

    Knox, J.B.; Smith, J.V.

    1984-09-01

    Geological and geophysical data suggest that during the evolution of the earth and its species, that there have been many mass extinctions due to large impacts from comets and large asteroids, and major volcanic events. Today, technology has developed to the stage where we can begin to consider protective measures for the planet. Evidence of the ecological disruption and frequency of these major events is presented. Surveillance and warning systems are most critical to develop wherein sufficient lead times for warnings exist so that appropriate interventions could be designed. The long term research undergirding these warning systems, implementation, and proof testing is rich in opportunities for collaboration for peace.

  9. Time-reversal methods in geophysics

    SciTech Connect

    Larmat, Carene S.; Guyer, Robert A.; Johnson, Paul A.

    2010-08-15

    Before the 20th century there were few seismometers. So Earth's dynamic geophysical processes were poorly understood. Today the potential for understanding those processes is enormous: The number of seismic instruments is continually increasing, their data are easily stored and shared, and computing power grows exponentially. As a result, seismologists are rapidly discovering new kinds of seismic signals in the frequency range 0.001-100 Hz, as well as relatively large nonseismic displacements, monitored by the global positioning system, occurring over days or weeks.

  10. Interactive Geophysical Mapping on the Web

    NASA Astrophysics Data System (ADS)

    Meertens, C.; Hamburger, M.; Estey, L.; Weingroff, M.; Deardorff, R.; Holt, W.

    2002-12-01

    We have developed a set of interactive, web-based map utilities that make geophysical results accessible to a large number and variety of users. These tools provide access to pre-determined map regions via a simple Html/JavaScript interface or to user-selectable areas using a Java interface to a Generic Mapping Tools (GMT) engine. Users can access a variety of maps, satellite images, and geophysical data at a range of spatial scales for the earth and other planets of the solar system. Developed initially by UNAVCO for study of global-scale geodynamic processes, users can choose from a variety of base maps (satellite mosaics, global topography, geoid, sea-floor age, strain rate and seismic hazard maps, and others) and can then add a number of geographic and geophysical overlays for example coastlines, political boundaries, rivers and lakes, NEIC earthquake and volcano locations, stress axes, and observed and model plate motion and deformation velocity vectors representing a compilation of 2933 geodetic measurements from around the world. The software design is flexible allowing for construction of special editions for different target audiences. Custom maps been implemented for UNAVCO as the "Jules Verne Voyager" and "Voyager Junior", for the International Lithosphere Project's "Global Strain Rate Map", and for EarthScope Education and Outreach as "EarthScope Voyager Jr.". For the later, a number of EarthScope-specific features have been added, including locations of proposed USArray (seismic), Plate Boundary Observatory (geodetic), and San Andreas Fault Observatory at Depth sites plus detailed maps and geographically referenced examples of EarthScope-related scientific investigations. In addition, we are developing a website that incorporates background materials and curricular activities that encourage users to explore Earth processes. A cluster of map processing computers and nearly a terabyte of disk storage has been assembled to power the generation of

  11. Geophysics publications honored

    NASA Astrophysics Data System (ADS)

    Geophysics and geology publications by the U.S. Geological Survey were awarded one first- and two third-place prizes at the ‘Blue Pencil’ ceremony last month, sponsored by the National Association of Government Communicators.First place in the news release category went to Frank Forrester, an AGU member and recently retired USGS information officer. Editors and artists of the bimonthly USGS Earthquake Information Bulletin were awarded third place in the category for technical magazines using at least two colors.

  12. Geophysical fluid dynamics: whence, whither and why?

    NASA Astrophysics Data System (ADS)

    Vallis, Geoffrey K.

    2016-08-01

    This article discusses the role of geophysical fluid dynamics (GFD) in understanding the natural environment, and in particular the dynamics of atmospheres and oceans on Earth and elsewhere. GFD, as usually understood, is a branch of the geosciences that deals with fluid dynamics and that, by tradition, seeks to extract the bare essence of a phenomenon, omitting detail where possible. The geosciences in general deal with complex interacting systems and in some ways resemble condensed matter physics or aspects of biology, where we seek explanations of phenomena at a higher level than simply directly calculating the interactions of all the constituent parts. That is, we try to develop theories or make simple models of the behaviour of the system as a whole. However, these days in many geophysical systems of interest, we can also obtain information for how the system behaves by almost direct numerical simulation from the governing equations. The numerical model itself then explicitly predicts the emergent phenomena-the Gulf Stream, for example-something that is still usually impossible in biology or condensed matter physics. Such simulations, as manifested, for example, in complicated general circulation models, have in some ways been extremely successful and one may reasonably now ask whether understanding a complex geophysical system is necessary for predicting it. In what follows we discuss such issues and the roles that GFD has played in the past and will play in the future.

  13. Geophysical fluid dynamics: whence, whither and why?

    PubMed Central

    2016-01-01

    This article discusses the role of geophysical fluid dynamics (GFD) in understanding the natural environment, and in particular the dynamics of atmospheres and oceans on Earth and elsewhere. GFD, as usually understood, is a branch of the geosciences that deals with fluid dynamics and that, by tradition, seeks to extract the bare essence of a phenomenon, omitting detail where possible. The geosciences in general deal with complex interacting systems and in some ways resemble condensed matter physics or aspects of biology, where we seek explanations of phenomena at a higher level than simply directly calculating the interactions of all the constituent parts. That is, we try to develop theories or make simple models of the behaviour of the system as a whole. However, these days in many geophysical systems of interest, we can also obtain information for how the system behaves by almost direct numerical simulation from the governing equations. The numerical model itself then explicitly predicts the emergent phenomena—the Gulf Stream, for example—something that is still usually impossible in biology or condensed matter physics. Such simulations, as manifested, for example, in complicated general circulation models, have in some ways been extremely successful and one may reasonably now ask whether understanding a complex geophysical system is necessary for predicting it. In what follows we discuss such issues and the roles that GFD has played in the past and will play in the future. PMID:27616918

  14. Geophysical fluid dynamics: whence, whither and why?

    PubMed

    Vallis, Geoffrey K

    2016-08-01

    This article discusses the role of geophysical fluid dynamics (GFD) in understanding the natural environment, and in particular the dynamics of atmospheres and oceans on Earth and elsewhere. GFD, as usually understood, is a branch of the geosciences that deals with fluid dynamics and that, by tradition, seeks to extract the bare essence of a phenomenon, omitting detail where possible. The geosciences in general deal with complex interacting systems and in some ways resemble condensed matter physics or aspects of biology, where we seek explanations of phenomena at a higher level than simply directly calculating the interactions of all the constituent parts. That is, we try to develop theories or make simple models of the behaviour of the system as a whole. However, these days in many geophysical systems of interest, we can also obtain information for how the system behaves by almost direct numerical simulation from the governing equations. The numerical model itself then explicitly predicts the emergent phenomena-the Gulf Stream, for example-something that is still usually impossible in biology or condensed matter physics. Such simulations, as manifested, for example, in complicated general circulation models, have in some ways been extremely successful and one may reasonably now ask whether understanding a complex geophysical system is necessary for predicting it. In what follows we discuss such issues and the roles that GFD has played in the past and will play in the future.

  15. Geophysical methods for road construction and maintenance

    NASA Astrophysics Data System (ADS)

    Rasul, Hedi; Karlson, Caroline; Jamali, Imran; Earon, Robert; Olofsson, Bo

    2015-04-01

    Infrastructure, such as road transportation, is a vital in civilized societies; which need to be constructed and maintained regularly. A large part of the project cost is attributed to subsurface conditions, where unsatisfactory conditions could increase either the geotechnical stabilization measures needed or the design cost itself. A way to collect information of the subsurface and existing installations which can lead to measures reducing the project cost and damage is to use geophysical methods during planning, construction and maintenance phases. The moisture in road layers is an important factor, which will affect the bearing capacity of the construction as well as the maintenances. Moisture in the road is a key factor for a well-functioning road. On the other hand the excessive moisture is the main reason of road failure and problems. From a hydrological point of view geophysical methods could help road planners identify the water table, geological strata, pollution arising from the road and the movement of the pollution before, during and after construction. Geophysical methods also allow road planners to collect valuable data for a large area without intrusive investigations such as with boreholes, i.e. minimizing the environmental stresses and costs. However, it is important to specify the investigation site and to choose the most appropriate geophysical method based on the site chosen and the objective of the investigation. Currently, numerous construction and rehabilitation projects are taking places around the world. Many of these projects are focused on infrastructural development, comprising both new projects and expansion of the existing infrastructural network. Geophysical methods can benefit these projects greatly during all phases. During the construction phase Ground Penetrating radar (GPR) is very useful in combination with Electrical Resistivity (ER) for detecting soil water content and base course compaction. However, ER and Electromagnetic

  16. Geophysical logs in British stratigraphy

    SciTech Connect

    Whittaker, A.; Holliday, D.W.; Penn, I.E.

    1985-01-01

    This Special Report outlines the stratigraphic applications of the main geophysical logging tools. It characterises the British geological succession by means of the geophysical log signatures of its principle constituent formations. A large amount of previously unpublished data is provided on a geographical area long known for its importance in the development of the science of stratigraphy. The book in units modern developments of petroleum industry geophysical techniques with long-established stratigraphical discovery/research. Contents include: Introduction; Types of logs commonly used; Some geological uses of geophysical logs; Log signatures in British Stratigraphy; References.

  17. Crustal movement and plate motion as observed by GPS baseline ranging - trial to make teaching materials for middle- and high-school earth science education by teachers

    NASA Astrophysics Data System (ADS)

    Matsumoto, T.

    2009-12-01

    Japanese government established the system for renewing educational personnel certificates in 2007 and mandated the adoption of it in April 2009 (cf. “2007 White Paper on Education, Culture, Sports, Science and Technology”, available at http://www.mext.go.jp/english/). The new system shows that the valid period for each regular certificate after the renewal system adoption (April 1, 2009) is until the end of the fiscal year after ten years from satisfying the qualifications required for the certificate. Only persons who have attended over 30 hours and passed the examination in the certificate renewal courses before the expiration of the valid period can renew their certificate which is valid for next ten years. The purpose of this system is for teachers to acquire the latest knowledge and skills. Certificate renewal courses authorized by Ministry of Education, Culture, Sports, Science and Technology of Japan are offered by universities. Attendees will choose based on their specialty and awareness of issues from the various courses with education curriculums and. To renew their certificates, they should include (1) items regarding the latest trends and issues in education (12 hours) and (2) items regarding their speciality and other educational enhancement (three 6-hours course: total 18 hours). In 2008, before the adoption, provisional certificate renewal courses were offered for trial by more than 100 universities. The author offered a 6-hour course titled by “Development of teaching materials for school pupils to make understand the dynamic motion of the earth - utilising the results of the GPS ranging”. This course was targeted mainly for science teachers of middle- and high-schools. The goal of this course was for the attendees to understand the role of GPS ranging for the direct observation of the crustal movement and plate motion, and to produce the teaching materials possibly used in the classrooms. The offering of this course is aiming finally at

  18. The Solid Earth

    NASA Astrophysics Data System (ADS)

    Fowler, C. M. R.

    2005-02-01

    The second edition of this acclaimed textbook has been brought fully up-to-date to reflect the latest advances in geophysical research. It is designed for students in introductory geophysics courses who have a general background in the physical sciences, including introductory calculus. New to this edition are a section of color plates and separate sections on the earth's mantle and core. The book also contains an extensive glossary of terms, and includes numerous exercises for which solutions are available to instructors from solutions@cambridge.org. First Edition Hb (1990): 0-521-37025-6 First Edition Pb (1990): 0-521-38590-3

  19. The Solid Earth

    NASA Astrophysics Data System (ADS)

    Fowler, C. M. R.

    2004-12-01

    The second edition of this acclaimed textbook has been brought fully up-to-date to reflect the latest advances in geophysical research. It is designed for students in introductory geophysics courses who have a general background in the physical sciences, including introductory calculus. New to this edition are a section of color plates and separate sections on the earth's mantle and core. The book also contains an extensive glossary of terms, and includes numerous exercises for which solutions are available to instructors from solutions@cambridge.org. First Edition Hb (1990): 0-521-37025-6 First Edition Pb (1990): 0-521-38590-3

  20. Geophysics and cosmogony of solar system

    NASA Astrophysics Data System (ADS)

    Kuzjmenko, G. I.; Smirnov, V. A.

    2003-04-01

    The attention to primary importance of geophysics in formation of modern representations about planets of Solar system is inverted. [ Kuzjmenko G.I. Deep Processes in the Earth's Interior. Geophys. J. 2001. Vol. 20, pp 813 -831; Kuzjmenko G.I., Smirnov V.A. Minor Bodys and Cosmogony of a Solar System. CAMMAC 2002. Intern. Conf. September 23 - 29, Vinnitsia, 2002, pp 35 -36]. The analysis rocket given about electromagnetic properties of Solar system has helped utilization Generalized Statistical-Wavemechanical Equations (GSWE), which special case is the quantum equation of Schrödinger. From GSWE the decision not only old problems of Solar system, but also prediction of presence of a belt of small bodies of Kuiper's and features of absent-minded substance in Solar system follows. The modern geophysical data on properties of the Earth with use GSWE result not only in the description of the electromagnetic characteristics of planets, but open existence dark mattery, which properties now are actively studied [Kuzjmenko G.I., Zelinsky I.P. Generalized Statistical-Wavemechanical Equations (GSWE) and its Applications. Proc. of 16-th IMACS World Congress 2000. Lausanne, Switzerland, August 21-25, 2000. CD File 416 -1].

  1. Guided earth boring tool

    SciTech Connect

    McDonald, W.J.; Pittard, G.T.; Maurer, W.C.; Wasson, M.R.; Herben, W.C.

    1989-08-22

    This patent describes a controllable tool for drilling holes in soft earth. The tool comprising an elongated rigid supporting drill rod or pipe, means supporting the drill rod or pipe for earth boring or piercing movement, including means for moving the drill rod or pipe longitudinally for penetrating the earth, means for rotating the drill rod or pipe while penetrating the earth, and means for controlling the direction of movement of the drill rod or pipe along a straight or curved path. The drill rod or pipe moving and rotating means being constructed to permit addition and removal of supporting drill rod or pipe during earth penetrating operation, an earth piercing member of substantially cylindrical shape. The tool being operable to penetrate the earth upon longitudinal movement of the drill rod or pipe by the longitudinal rod or pipe moving means, and the direction controlling means comprising means causing drill rod or pipe movement in a curved path through the earth when the rod or pipe is not rotated and causing drill rod or pipe straight line movement when the rod or pipe is rotated.

  2. Sampling functions for geophysics

    NASA Technical Reports Server (NTRS)

    Giacaglia, G. E. O.; Lunquist, C. A.

    1972-01-01

    A set of spherical sampling functions is defined such that they are related to spherical-harmonic functions in the same way that the sampling functions of information theory are related to sine and cosine functions. An orderly distribution of (N + 1) squared sampling points on a sphere is given, for which the (N + 1) squared spherical sampling functions span the same linear manifold as do the spherical-harmonic functions through degree N. The transformations between the spherical sampling functions and the spherical-harmonic functions are given by recurrence relations. The spherical sampling functions of two arguments are extended to three arguments and to nonspherical reference surfaces. Typical applications of this formalism to geophysical topics are sketched.

  3. A Directory of Societies in Earth Science.

    ERIC Educational Resources Information Center

    Geotimes, 1981

    1981-01-01

    Lists the titles and addresses of approximately 450 domestic and foreign organizations which deal with earth science fields, including geology, paleontology, mining, and geophysics. Also listed are U.S. state geological surveys. (WB)

  4. A Directory of Societies in Earth Science.

    ERIC Educational Resources Information Center

    Geotimes, 1981

    1981-01-01

    Lists the titles and addresses of approximately 450 domestic and foreign organizations which deal with earth science fields, including geology, paleontology, mining, and geophysics. Also listed are U.S. state geological surveys. (WB)

  5. Development of Geophysical Ideas and Institutions in Ottoman Empire

    NASA Astrophysics Data System (ADS)

    Ozcep, Ferhat; Ozcep, Tazegul

    2015-04-01

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

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

    NASA Astrophysics Data System (ADS)

    Ozcep, F.; Ozcep, T.

    2014-09-01

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

  7. Prediction of Geophysical Flow Mobility

    NASA Astrophysics Data System (ADS)

    Cagnoli, B.; Piersanti, A.

    2014-12-01

    The prediction of the mobility of geophysical flows to assess their hazards is one of the main research goals in the earth sciences. Our laboratory experiments and numerical simulations are carried out to understand the effects of grain size and flow volume on the mobility of the centre of mass of dry granular flows of angular rock fragments that have pyroclastic flows and rock avalanches as counterpart in nature. We focus on the centre of mass because it provides information about the intrinsic ability of a flow to dissipate more or less energy as a function of its own features. We show that the grain size and flow volume effects can be expressed by a linear relationship between scaling parameters where the finer the grain size or the smaller the flow volume, the more mobile the centre of mass of the granular flow. The grain size effect is the result of the decrease of particle agitation per unit of flow mass, and thus, the decrease of energy dissipation per unit of travel distance, as grain size decreases. In this sense, flows with different grain sizes are like cars with engines with different fuel efficiencies. The volume effect is the result of the fact that the deposit accretes backward during its formation on a slope change (either gradual or abrupt). We adopt for the numerical simulations a 3D discrete element modeling which confirms the grain size and flow volume effects shown by the laboratory experiments. This confirmation is obtained without prior fine tuning of the parameter values to get the desired output. The numerical simulations reveal also that the larger the initial compaction of the granular mass before release, the more mobile the flow. This behaviour must be taken into account to prevent misinterpretation of laboratory and field data. Discrete element modeling predicts the correct effects of grain size and flow volume because it takes into consideration particle interactions that are responsible for the energy dissipated by the flows.

  8. Non equilibrium statistical mechanics of geophysical flows

    NASA Astrophysics Data System (ADS)

    Bouchet, F.

    2012-04-01

    Onsager first proposed to explain the self organization of turbulent flows using the statistical mechanics framework. Generalization of those ideas to the class of 2D-Euler and Quasi-Gestrophic models led to the Robert-Sommeria-Miller theory. This approach was successful in modeling many geophysical phenomena: the Great Red Spot of Jupiter [2, 1], drift of mesoscale ocean vortices [3, 1], self-organization of Quasi-Geostrophic dynamics in mid-basin jets similar to the Gulf-Stream and the Kuroshio [3, 1], and so on. However, this type of equilibrium theories fail to take into account forces and dissipation. This is a strong limitation for many geophysical phenomena. Interestingly, it is possible to circumvent these difficulties using the most modern theoretical development of non-equilibrium statistical mechanics: large deviation [4] and instanton theories. As an example, we will discuss geophysical turbulent flows which have more than one attractor (bistability or mutistability). For instance, paths of the Kuroshio [5], the Earth's magnetic field reversal, atmospheric flows [6], MHD experiments [7], 2D turbulence experiments [8, 9], 3D flows [10] show this kind of behavior. On Navier-Stokes and Quasi-Geostrophic turbulent flows, we predict the conditions for existence of rare transitions between attractors, and the dynamics of those transitions. We discuss how these results are probably connected to the long debated existence of multi-stability in the atmosphere and oceans, and how non-equilibrium statistical mechanics can allow to settle this issue. Generalization of statistical mechanics to more comprehensive hydrodynamical models, which include gravity wave dynamics and allow for the possibility of energy transfer through wave motion, would be extremely interesting. Namely, both are essential in understanding energy balance of geophysical flows. However, due to difficulties in essential theoretical parts of the statistical mechanics approach, previous methods

  9. Space Geodesy Monitoring Mass Transport in Global Geophysical Fluids

    NASA Technical Reports Server (NTRS)

    Chao, Benjamin F.

    2004-01-01

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

  10. ROMY: A 4-component large ring laser for geophysics

    NASA Astrophysics Data System (ADS)

    Igel, H.; Schreiber, K. U.; Gebauer, A.; Wassermann, J. M.; Lin, C. J.; Bernauer, F.; Simonelli, A.; Wells, J. P. R.

    2016-12-01

    Observatory-based ring lasers are currently the most sensitive technology for measurements of rotational ground motions (seismology) and variations of Earth's rotation rate. Ring laser have so far been limited to single components only (e.g., the horizontal G-ring in Wettzell, Germany, measuring the rotation around a vertical axis). Within the ROMY project (www.romy-erc.eu) funded by the European Research Council we designed and constructed the first multi-component ring laser system for geophysics. The 4-component, tetrahedral-shaped, top-down ring laser sits on a connected concrete structure embedded underground 2m below the surface at the Geophysical Observatory Fürstenfeldbruck, Germany. The 4 independent equilateral triangular-shaped He-Ne ring lasers with 12 m side length are expected to resolve rotational motions below 12 prad/s/sqrt(Hz). We will report on the design and construction process of this first-of-its-kind ring laser system, with completion expected in August 2016 by which time the optical systems are beginning to be assembled. The four rotational components are combined to the complete 3-component vector of Earth's rotation, perturbed by other geophysical signals such as earthquake induced ground motions, ocean-generated noise, Earth's free oscillations, interactions between atmosphere and solid Earth and other signals. First applications are expected in the field of seismology. We report on future plans to stabilize the ring geometry providing long-term stability for geodetic applications.

  11. Space Geodesy Monitoring Mass Transport in Global Geophysical Fluids

    NASA Technical Reports Server (NTRS)

    Chao, Benjamin F.

    2004-01-01

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

  12. Jesuit Geophysical Observatories

    NASA Astrophysics Data System (ADS)

    Udias, Agustin; Stauder, William

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

  13. A ``model`` geophysics program

    SciTech Connect

    Nyquist, J.E.

    1994-03-01

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

  14. Movement Disorders

    MedlinePlus

    ... want them to. If you have a movement disorder, you experience these kinds of impaired movement. Dyskinesia ... and is a common symptom of many movement disorders. Tremors are a type of dyskinesia. Nerve diseases ...

  15. Bowel Movement

    MedlinePlus

    A bowel movement is the last stop in the movement of food through your digestive tract. Your stool passes out of ... what you eat and drink. Sometimes a bowel movement isn't normal. Diarrhea happens when stool passes ...

  16. Satellite-tracking and Earth dynamics research programs

    NASA Technical Reports Server (NTRS)

    1983-01-01

    Tracking of LAGEOS for polar motion and Earth rotation studies and for other geophysical investigations, including crustal dynamics, Earth and ocean tides, and the general development of precision orbit determination continues. The BE-C and Starlette satellites were tracked for refined determinations of station coordinates and the Earth's gravity field and for studies of solid Earth dynamics.

  17. Inversion Algorithms for Geophysical Problems

    DTIC Science & Technology

    1987-12-16

    ktdud* Sccumy Oass/Kjoon) Inversion Algorithms for Geophysical Problems (U) 12. PERSONAL AUTHOR(S) Lanzano, Paolo 13 «. TYPE OF REPORT Final 13b...spectral density. 20. DISTRIBUTION/AVAILABILITY OF ABSTRACT 13 UNCLASSIFIED/UNLIMITED D SAME AS RPT n OTIC USERS 22a. NAME OF RESPONSIBLE...Research Laboratory ’^^ SSZ ’.Washington. DC 20375-5000 NRLrMemorandum Report-6138 Inversion Algorithms for Geophysical Problems p. LANZANO Space

  18. Geophysical fluid flow cell experiment

    NASA Technical Reports Server (NTRS)

    Hart, J. E.

    1982-01-01

    The primary purpose of the geophysical flow experiments is to simulate large-scale baroclinic (density-stratified) flows which occur naturally in the atmospheres of rotating planets and stars and to gain insights and obtain answers to crucial questions concerning the large-scale nonlinear mechanics of the global geophysical flows. Those external conditions related to fluid viscosity, rotation, gravity are identified, which allow qualitatively different modes of instability or waves in the model.

  19. Nonlinear Geophysics: Why We Need It

    NASA Astrophysics Data System (ADS)

    Lovejoy, Shaun; Agterberg, Fritz; Carsteanu, Alin; Cheng, Qiuming; Davidsen, Joern; Gaonac'h, Hélène; Gupta, Vijay; L'Heureux, Ivan; Liu, William; Morris, Stephen W.; Sharma, Surjalal; Shcherbakov, Robert; Tarquis, Ana; Turcotte, Donald; Uritsky, Vadim

    2009-12-01

    Few geoscientists would deny that effects are often sensitively dependent on causes, or that their amplification is commonly so strong as to give rise to qualitatively new “emergent” properties, or that geostructures are typically embedded one within another in a hierarchy. Starting in the 1980s, a growing number felt the need to underline the absolute importance of such nonlinearity through workshops and conferences. Building on this, the European Geosciences Union (EGU) organized a nonlinear processes (NP) section in 1990; AGU established a nonlinear geophysics (NG) focus group in 1997; and both unions began collaborating on an academic journal, Nonlinear Processes in Geophysics, in 1994. The disciplines coalescing in the NG movement are united by the fact that many disparate phenomena show similar behaviors when seen in a proper nonlinear prism. This hints at some fundamental laws of self-organization and emergence that describe real nature instead of linear, reductive paradigms that at best capture only small perturbations to a solved state or problem.

  20. Planetary Geophysics and Tectonics

    NASA Technical Reports Server (NTRS)

    Zuber, Maria

    2005-01-01

    The broad objective of this work is to improve understanding of the internal structures and thermal and stress histories of the solid planets by combining results from analytical and computational modeling, and geophysical data analysis of gravity, topography and tectonic surface structures. During the past year we performed two quite independent studies in the attempt to explain the Mariner 10 magnetic observations of Mercury. In the first we revisited the possibility of crustal remanence by studying the conditions under which one could break symmetry inherent in Runcorn's model of a uniformly magnetized shell to produce a remanent signal with a dipolar form. In the second we applied a thin shell dynamo model to evaluate the range of intensity/structure for which such a planetary configuration can produce a dipole field consistent with Mariner 10 results. In the next full proposal cycle we will: (1) develop numerical and analytical and models of thin shell dynamos to address the possible nature of Mercury s present-day magnetic field and the demise of Mars magnetic field; (2) study the effect of degree-1 mantle convection on a core dynamo as relevant to the early magnetic field of Mars; (3) develop models of how the deep mantles of terrestrial planets are perturbed by large impacts and address the consequences for mantle evolution; (4) study the structure, compensation, state of stress, and viscous relaxation of lunar basins, and address implications for the Moon s state of stress and thermal history by modeling and gravity/topography analysis; and (5) use a three-dimensional viscous relaxation model for a planet with generalized vertical viscosity distribution to study the degree-two components of the Moon's topography and gravity fields to constrain the primordial stress state and spatial heterogeneity of the crust and mantle.

  1. Monitoring Vadose Zone Desiccation with Geophysical Methods

    SciTech Connect

    Truex, Michael J.; Johnson, Timothy C.; Strickland, Christopher E.; Peterson, John E.; Hubbard, Susan S.

    2013-05-01

    Soil desiccation was recently field tested as a potential vadose zone remediation technology. Desiccation removes water from the vadose zone and significantly decreases the aqueous-phase permeability of the desiccated zone, thereby decreasing movement of moisture and contaminants. The 2-D and 3-D distribution of moisture content reduction over time provides valuable information for desiccation operations and for determining when treatment goals have been reached. This type of information can be obtained through use of geophysical methods. Neutron moisture logging, cross-hole electrical resistivity tomography, and cross-hole ground penetrating radar approaches were evaluated with respect to their ability to provide effective spatial and temporal monitoring of desiccation during a treatability study conducted in the vadose zone of the DOE Hanford Site in WA.

  2. Unleashing Geophysics Data with Modern Formats and Services

    NASA Astrophysics Data System (ADS)

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

    2016-04-01

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

  3. Earth Science

    NASA Image and Video Library

    1994-09-02

    This image depicts a full view of the Earth, taken by the Geostationary Operational Environment Satellite (GOES-8). The red and green charnels represent visible data, while the blue channel represents inverted 11 micron infrared data. The north and south poles were not actually observed by GOES-8. To produce this image, poles were taken from a GOES-7 image. Owned and operated by the National Oceanic and Atmospheric Administration (NOAA), GOES satellites provide the kind of continuous monitoring necessary for intensive data analysis. They circle the Earth in a geosynchronous orbit, which means they orbit the equatorial plane of the Earth at a speed matching the Earth's rotation. This allows them to hover continuously over one position on the surface. The geosynchronous plane is about 35,800 km (22,300 miles) above the Earth, high enough to allow the satellites a full-disc view of the Earth. Because they stay above a fixed spot on the surface, they provide a constant vigil for the atmospheric triggers for severe weather conditions such as tornadoes, flash floods, hail storms, and hurricanes. When these conditions develop, the GOES satellites are able to monitor storm development and track their movements. NASA manages the design and launch of the spacecraft. NASA launched the first GOES for NOAA in 1975 and followed it with another in 1977. Currently, the United States is operating GOES-8, positioned at 75 west longitude and the equator, and GOES-10, which is positioned at 135 west longitude and the equator. (GOES-9, which malfunctioned in 1998, is being stored in orbit as an emergency backup should either GOES-8 or GOES-10 fail. GOES-11 was launched on May 3, 2000 and GOES-12 on July 23, 2001. Both are being stored in orbit as a fully functioning replacement for GOES-8 or GOES-10 on failure.

  4. Comparison of different models of geophysical excitation in nutation

    NASA Astrophysics Data System (ADS)

    Ron, Cyril; Vondrák, Jan

    2015-04-01

    Celestial pole offsets caused by the excitations of geophysical fluids (atmosphere, ocean) and geomagnetic fields (geomagnetic jerks) are computed for a non-rigid Earth model to account for the realistic Earth's response by using the integration of the broad-band Liouville equations. The results are compared with the celestial pole offsets observed by Very Long-Baseline Interferometry. In our previous study we demonstrated that the application of a synthetic excitation in the epoch of the geomagnetic jerks improves significantly the agreement between the integrated and observed celestial pole offsets. In the presented study we focus on the analysis of differencies between the integrated series excited by different models of geophysical fluids, the U.S. model NCEP/NCAR and the European models ERA supplemented with the ocean model OMCT provided by GFZ Potsdam.

  5. Dunlop receives European Geophysical Society's Néel Medal

    NASA Astrophysics Data System (ADS)

    Tauxe, Lisa

    David J. Dunlop of the Physics Department and Erindale College at the University of Toronto has been awarded the 1999 Louis Néel Medal of the European Geophysical Society (EGS) for “authoritative contributions to rock magnetism, setting the standards for future decades.” The medal will be presented to Dunlop in April in a special ceremony at the Nederlands Congresbebouw in The Hague, The Netherlands, during the 24th General Assembly of the EGS.The Néel Medal is awarded by the Solid Earth Geophysics section of EGS in recognition of the scientific achievements of Louis Néel, who shared the 1970 Nobel Prize in Physics for his fundamental discoveries in magnetism.The medal is awarded “for outstanding achievements in the fertilization of the Earth Sciences by the transfer and application of fundamental theory and/or experimental techniques of solid state physics, defined in its broadest sense.”

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

    SciTech Connect

    1995-12-31

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

  7. Integrated Geophysical Methods Applied to Geotechnical and Geohazard Engineering: From Qualitative to Quantitative Analysis and Interpretation

    NASA Astrophysics Data System (ADS)

    Hayashi, K.

    2014-12-01

    The Near-Surface is a region of day-to-day human activity on the earth. It is exposed to the natural phenomena which sometimes cause disasters. This presentation covers a broad spectrum of the geotechnical and geohazard ways of mitigating disaster and conserving the natural environment using geophysical methods and emphasizes the contribution of geophysics to such issues. The presentation focusses on the usefulness of geophysical surveys in providing information to mitigate disasters, rather than the theoretical details of a particular technique. Several techniques are introduced at the level of concept and application. Topics include various geohazard and geoenvironmental applications, such as for earthquake disaster mitigation, preventing floods triggered by tremendous rain, for environmental conservation and studying the effect of global warming. Among the geophysical techniques, the active and passive surface wave, refraction and resistivity methods are mainly highlighted. Together with the geophysical techniques, several related issues, such as performance-based design, standardization or regularization, internet access and databases are also discussed. The presentation discusses the application of geophysical methods to engineering investigations from non-uniqueness point of view and introduces the concepts of integrated and quantitative. Most geophysical analyses are essentially non-unique and it is very difficult to obtain unique and reliable engineering solutions from only one geophysical method (Fig. 1). The only practical way to improve the reliability of investigation is the joint use of several geophysical and geotechnical investigation methods, an integrated approach to geophysics. The result of a geophysical method is generally vague, here is a high-velocity layer, it may be bed rock, this low resistivity section may contain clayey soils. Such vague, qualitative and subjective interpretation is not worthwhile on general engineering design works

  8. 1994 Geophysical images contest entries sought

    NASA Astrophysics Data System (ADS)

    As part of AGU's 75th Anniversary year, entries are sought for the 1994 Geophysical Images Contest. Over ninety photographs, computer graphics, posters, maps, slides, and videos were submitted in 1993. The winning images were displayed at the AGU Spring Meeting in Baltimore, and again at the Fall Meeting in San Francisco, along with the other images submitted.First place winner in the computer graphics section was “Western Mediterranean Sea Salinity Field,” submitted by Jacques Haus. Honorable Mentions went to Wei-jia Su for “A View of Whole Mantle Heterogeneity” and Toshiro Tanimoto, Paul Morin, David Yuen, and Yu-Shen Zhang for “Visualization of the Earth's Upper Mantle.”

  9. Surveying and Geophysical Measurements with Inertial Rotation Sensors

    DTIC Science & Technology

    1978-01-01

    measuring the annuial wobble and Chandler wobble with 0.1%~ resolution appears feasible. Otfier GeopbvsieMl Aflnlicationg meauremenimof tilt plus Verti’-al... wobble might be feasible by monitoring azimuth and astronomic latitude in geophysical observatories. FORM DD 𔃻JAN 73 1473 EDITION OF I NOV S IS...earth’s Pole of’ rotation wobbles , nutatcs, preee ,sma-.rnd wamdes(2 andtee oin aeostral by optical astrometry, lunar and artificial satellite laser

  10. Research e-infrastructure for "Geophysics" mission.

    NASA Astrophysics Data System (ADS)

    Nazarov, V.; Mogilevsky, M.; Nazirov, R.; Eismont, N.; Melnik, A.

    2009-04-01

    Space mission "Geophysics" intended for monitoring of ionospheric plasma parameters, electromagnetic emission and solar activity. In the frame of the project will be launched five small satellites on solar-synchronous orbits: two satellites on circular orbit, altitude ~700 km, orbit plane - morning-evening, another two satellites at the same altitude but orbit plane - day-night and the last satellite - on elliptic orbit with ~1200 km apogee and ~400 km perigee. Such choice of spacecraft constellation configuration is so some extent similar to the configuration usually used for the Earth remote sensing tasks. It gives advantages for the project because it allows to apply technologies of remote sensing satellites practically off shelved. From the other side it gives new possibilities for geophysics experiments followed from the fact that the measurements may be considered as the ones done by the instruments having the size of the Earth scale. However it brings more strict requirements for information support of the mission in general and for ground segment particularly. In needs not only on-line processing but on-line interpretation too, operative feedback link between interpretation and operation subsystems etc. Satisfaction of such strict requirements from one side and necessity for using of existing ground resources (taking in account budget limitations) implied creating of unified ground information infrastructure for target payload of the mission. This e-infrastructure will cover traditional ground systems which are treated as systems based on Resource-Oriented Architecture (ROA) and will produce unified integration platform based on Service-Oriented Architecture (SOA) which will collects all needed services and provides access to them in frame of unified cyber-infrastructure. The article describes technology and methodology aspects of design of this system.

  11. A New Social Contract for Geophysics

    NASA Astrophysics Data System (ADS)

    Malone, T. F.

    2002-12-01

    The Golden Age for geophysical research that followed the IGY set the stage for a new era of interaction among science, technology, and society. World population and the average economic productivity of individuals have both continued to grow exponentially during the past 50 years with the result that by the 1980s the demands of the human economy on the finite renewable resources of planet Earth were approximately equal to the natural regenerative capacities of planetary ecosystems. These demands are now "overshooting" those regenerative powers by about 20 per cent (1). The result could be a collapse in the life-supporting capacity of global ecosystems during coming decades, with tragic implications for civilized society. Novel modes of collaboration among all disciplines and all sectors of society are urgently needed to transform a potential catastrophe into the attractive vision that is now within reach as a result of rapidly expanding human knowledge, emerging technologies for sharing that knowledge (2), and the set of ethical principles for sustainable development contained in the Earth Charter (3). This prospect challenges geophysicists and scholars in all disciplines to forge a new and broadly based contract with society (4). 1. Wackernagel M. et al. 2002. "Tracking the ecological overshoot of the human economy." Proc. Natl. Acad. Sci. USA, Vol. 99, Issue 14, 9266-9271, July 9. 2. Malone T. and Yohe G. 2002. "Knowledge partnerships for a sustainable, equitable, and stable society." J. of Knowledge Management, Vol. 6, No. 4, October (in press). 3. www.earthcharter.org 4. Malone T. 1997. "Building on the legacies of the Intenational Geophysical Year." Transactions, AGU, Vol.78, No. 15, pp. 185-191.

  12. Constrained optimization schemes for geophysical inversion of seismic data

    NASA Astrophysics Data System (ADS)

    Sosa Aguirre, Uram Anibal

    Many experimental techniques in geophysics advance the understanding of Earth processes by estimating and interpreting Earth structure (e.g., velocity and/or density structure). These techniques use different types of geophysical data which can be collected and analyzed separately, sometimes resulting in inconsistent models of the Earth depending on data quality, methods and assumptions made. This dissertation presents two approaches for geophysical inversion of seismic data based on constrained optimization. In one approach we expand a one dimensional (1-D) joint inversion least-squares (LSQ) algorithm by introducing a constrained optimization methodology. Then we use the 1-D inversion results to produce 3-D Earth velocity structure models. In the second approach, we provide a unified constrained optimization framework for solving a 1-D inverse wave propagation problem. In Chapter 2 we present a constrained optimization framework for joint inversion. This framework characterizes 1-D Earth's structure by using seismic shear wave velocities as a model parameter. We create two geophysical synthetic data sets sensitive to shear velocities, namely receiver function and surface wave dispersion. We validate our approach by comparing our numerical results with a traditional unconstrained method, and also we test our approach robustness in the presence of noise. Chapter 3 extends this framework to include an interpolation technique for creating 3-D Earth velocity structure models of the Rio Grande Rift region. Chapter 5 introduces the joint inversion of multiple data sets by adding delay travel times information in a synthetic setup, and leave the posibility to include more data sets. Finally, in Chapter 4 we pose a 1-D inverse full-waveform propagation problem as a PDE-constrained optimization program, where we invert for the material properties in terms of shear wave velocities throughout the physical domain. We facilitate the implementation and comparison of different

  13. Stereotypical movements.

    PubMed

    Delafield-Butt, J T

    2010-01-01

    A 'stereotypical movement' denotes a movement reproduced in a standardised form. The term is used in two fields, in movement science and in medical assessments of pathology. The former recognises the occurrence of regular patterns of movement across individuals expressed at regular points in development, such as the pre-reach in early infancy. The latter specifies a pathological form of repetitive movement by one individual symptomatic of, for example, autism. This entry explores the interindividual use of the term in movement science and touches on ongoing work to better classify and quantify stereotypical movements for better psychophysiological understanding of action development, and possible sensitive measures of them.

  14. The Expanding Marketplace for Applied Geophysics

    NASA Astrophysics Data System (ADS)

    Carlson, N.; Sirles, P.

    2012-12-01

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

  15. Spatio-Temporal Modeling of the Earth Events and Moving of Celestial Bodies

    NASA Astrophysics Data System (ADS)

    Bulatova, Natalia P.

    2011-09-01

    It is well known that periodical and cyclical movements of cosmic sources of gravitation considerably affect Earth's geospheres (atmosphere, hydrosphere, crust, etc.) by producing tides and related phenomena, as well as the state of tectonic blocks, lithosphere plates and deep crust fractures. The result of such influence may be earthquakes and other catastrophes. Nowadays, the question modeling of geophysical processes is considerably actual. Thus studies in area of Earth' sciences have been moved from practice of observation of separate phenomena to the systematic quantitative investigation in interdisciplinary areas. A system of two modules is proposed by the author each using its own system of coordinates: (1) the model of three-dimensional spherical body of the Earth with the system of coordinates (III) including the time of events that happened on the Earth and (2) a compact model of the relative motion of celestial bodies in space and time as vectors that are changing their directions. Note the data bases of the Earth sciences have been used to construct the module (1), while the module (2) has been built using astronomic parameters of celestial bodies. The module (2) is known as "Method of moving source" (MDS) [1, 2]. As a result, on the basis of systematization, joint analysis and complexity of cosmic data and databases of Earth sciences the cause-and-effect relations between events on Earth and space bodies are established.

  16. Geophysical weight loss diet

    NASA Astrophysics Data System (ADS)

    Schatten, Kenneth

    1984-04-01

    Having for numerous reasons acquired a three digit kilogram mass, the author is experienced at the painful struggles that the gourmand must suffer to reduce weight, particularly if he/she enjoys reasonably large amounts of good food. To the avant-garde geophysicist, utilizing the following approach could be pleasurable, rewarding, and may even enable the accomplishment of what Ghengis Khan, Alexander the Great, Napolean, and Hitler could not!The basic approach is the full utilization of Newton's formula for the attraction of two massive bodies: F=GM1M2/r2, where G, is the gravitational constant; r, the distance between the two bodies; and M1 and M2, the masses of the two bodies. Although one usually chooses M1 to be the earth's mass ME and M2 to be the mass of a small object, this unnecessarily restricts the realm of phenomena. The less restrictive assumption is M1 + M2 = ME.

  17. An index of geophysical well logging in Virginia by the U.S. Geological Survey

    USGS Publications Warehouse

    Mulheren, M. Patrick; Larson, J.D.; Hopkins, Herbert T.

    1982-01-01

    Geophysical logs have been obtained in more than 170 wells in Virginia by the U.S. Geological Survey since 1968. These logs include natural gamma, electric, caliper, temperature, fluid conductivity, and fluid velocity. Most of the logs are for wells in the Coastal Plain Province of eastern Virginia. Geophysical logs aid in the interpretation of properties of earth materials, including the capacity to store and transmit water in the immediate vicinity of the well bore.

  18. Exotic geophysical phenomena observed in an environmental neutron flux study using EAS PRISMA detectors

    NASA Astrophysics Data System (ADS)

    Alekseenko, Victor; Bagrova, Anastasia; Cui, Shuwang; He, Yayun; Li, Bingbing; Ma, Xinhua; Pozdnyakov, Egor; Shchegolev, Oleg; Stenkin, Yuri; Stepanov, Vladimir

    2017-06-01

    Some exotic geophysical events are observed by a global net of electron-neutron detectors (en-detectors) developed in the framework of the PRISMA EAS project. Our en-detectors running both on the Earth's surface and underground are continuously measuring the environmental thermal neutron flux. Thermal neutrons are in equilibrium with media and are therefore sensitive to many geophysical phenomena, which are exotic for people studying ultra high-energy cosmic rays or carrying out low background experiments deep underground.

  19. Geophysical subsurface imaging and interface identification.

    SciTech Connect

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

    2005-09-01

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

  20. Educational Geophysics at INGV, Rome (Italy)

    NASA Astrophysics Data System (ADS)

    Dida Working Group Ingv,.

    2002-12-01

    Italy is a country prone to Earth phenomena such as earthquakes, volcanic eruptions, floods and landslides that left a trace in the memory of people. About 60% of the Italian territory is classified in the current seismic hazard maps, and large cities as Neaples and Catania are located close to the two largest active volcanoes of Europe (Mt. Vesuvius and Mt. Etna, respectively). Nevertheless, school programs are often inadequate about the natural hazards of the country. For this reason there are many requests from schoolteachers to visit with their classes the academic Institutions and to attend geophysical talks. The working group for educational activities of the Istituto Nazionale di Geofisica and Vulcanologia promotes and realizes Earth science outreach programs devoted to increase the knowledge of geophysical topics. The educational activity is one of the most important tasks of our Institution together with the research activities and the 24-hours survey of the Italian Seismic Network. The INGV hosts in its headquarter of Rome many visits of primary, secondary and high schools with an increasing demand year by year. Every year about 3,000 students visit our Institute over more than 60 open-days, and we participate to exhibitions and outreach projects organized by several Institutions. We show here what has been done at INGV for the geophysical education, underlining the problems and the successes of these activities. We describe also an educational project developed together with a teacher's team of secondary-school. Aim of this experience was to stimulate the interest of 12-year-old kids to unfamiliar arguments like seismology. The class was introduced to physical topics as waves and wave propagation by means of simple experiments. Then they visited the INGV were the research activities were shown, with emphasis on seismological studies; they were also thought how the Italian Seismic Network monitors earthquakes and how to use the P and S waves for their

  1. Learning about hydrothermal volcanic activity by modeling induced geophysical changes

    NASA Astrophysics Data System (ADS)

    Currenti, Gilda M.; Napoli, Rosalba

    2017-05-01

    Motivated by ongoing efforts to understand the nature and the energy potential of geothermal resources, we devise a coupled numerical model (hydrological, thermal, mechanical), which may help in the characterization and monitoring of hydrothermal systems through computational experiments. Hydrothermal areas in volcanic regions arise from a unique combination of geological and hydrological features which regulate the movement of fluids in the vicinity of magmatic sources capable of generating large quantities of steam and hot water. Numerical simulations help in understanding and characterizing rock-fluid interaction processes and the geophysical observations associated with them. Our aim is the quantification of the response of different geophysical observables (i.e. deformation, gravity and magnetic field) to hydrothermal activity on the basis of a sound geological framework (e.g. distribution and pathways of the flows, the presence of fractured zones, caprock). A detailed comprehension and quantification of the evolution and dynamics of the geothermal systems and the definition of their internal state through a geophysical modeling approach are essential to identify the key parameters for which the geothermal system may fulfill the requirements to be exploited as a source of energy. For the sake of illustration only, the numerical computations are focused on a conceptual model of the hydrothermal system of Vulcano Island by simulating a generic 1-year unrest and estimating different geophysical changes. We solved (i) the mass and energy balance equations of flow in porous media for temperature, pressure and density changes, (ii) the elastostatic equation for the deformation field and (iii) the Poisson’s equations for gravity and magnetic potential fields. Under the model assumptions, a generic unrest of 1-year engenders on the ground surface low amplitude changes in the investigated geophysical observables, that are, however, above the accuracies of the modern

  2. Object Storage for Geophysical Data

    NASA Astrophysics Data System (ADS)

    Habermann, T.; Readey, J.

    2015-12-01

    Object storage systems (such as Amazon S3 or Ceph) have been shown to be cost-effective and highly scalable for data repositories in the Petabyte range and larger. However traditionally data storage used for geophysical software systems has centered on file-based systems and libraries such as NetCDF and HDF5. In this session we'll discuss the advantages and challenges of moving to an object store-based model for geophysical data. We'll review a proposed model for a geophysical data service that provides an API-compatible library for traditional NetCDF and HDF5 applications while providing high scalability and performance. One further advantage of this approach is that any dataset or dataset selection can be referenced as a URI. By using versioning, the data the URI references can be guaranteed to be unmodified, thus enabling reproducibility of referenced data.

  3. Geophysics Fatally Flawed by False Fundamental Philosophy

    NASA Astrophysics Data System (ADS)

    Myers, L. S.

    2004-05-01

    volcanoes, that enable planetary expansion the same way cranial sutures permit human skulls to grow to maturity. Expansion is shown by the Asian and Australian trenches, from Kamchatka to the Marianas, and from Samoa to the tip of Macquarie Ridge south of New Zealand, that are mirror images of the western coasts of North and South America. This is clear evidence neither the Atlantic nor the Pacific Ocean existed 250 Ma when Earth was much smaller. In just 250 Ma external accretion and internal core expansion increased Earth's diameter from 7640 km to 12,735 km and increased total surface area to 361,060,000 sq. km, the area occupied by today's oceans-oceans that did not exist 250 Ma when Earth was slightly larger than Mars is today \\(6787 km\\). The fallacy of the nebular hypothesis did not become apparent until after Oliver and Isacks introduced the concept of subduction in 1967. Subduction was based on the false assumption that Earth's diameter is constant and unchanging, and spawned the theory of Plate Tectonics that "revolutionized" geophysics in a short period of time-a "revolution" destined for failure. Evidence is presented showing all solar bodies originate as comets \\(fragments of supernovae explosions\\) captured by the Sun that become meteoroids or asteroids by external accretion of meteorites and dust from over 370 known meteor streams.\\(Terentjeva, 1964\\) Accreation replaces the nebular hypothesis and rejuvenates Carey's Earth Expansion theory that, unfortunately, was pushed aside by plate tectonics because it lacked a plausible mechanism. However, expansion carries an ultimate threat to Mankind's tenure on Earth and exploration of Mars as the future home of Mankind takes on added significance.

  4. Ostracod provincialism and migration as a response to movements of Earth's plates: Cretaceous-Paleogene ostracods of West Africa, North Africa and the Middle East

    NASA Astrophysics Data System (ADS)

    Elewa, Ashraf M. T.

    2017-10-01

    This paper documents the Cretaceous -Paleogene ostracods response as the continental plates tend to show divergence. For example, in the intervals from the Early to Late Cretaceous when the South American plate tended to exhibit divergent movement westward from the African plate, the migration of ostracods show westward trend from Northeast Africa to West Africa; whereas, the divergence of the Indian and the Australian plates as well as the Antarctic plate from the African and the Eurasian plates, and Arabia is accompanied with ostracod migration southward. Another example from the Maastrichtian-Eocene ostracods of West Africa, where ostracods exhibit east-west migration (despite the migration of epineritic ostracods in both directions; east-west and vice-versa) towards the North American and South American plates. These trends of migration towards the deep oceans (Atlantic and Indian oceans of present time) indicate the tendency of ostracods of these geologic times towards endemism in the deep oceans resulted from seafloor spreading during the divergence of the continental plates. On the other hand, the paleoenvironmental changes should also have significant effect on these trends of migration.

  5. A substantiation of cyclic process of the system Earth-Moon-Sun tidal evolution

    NASA Astrophysics Data System (ADS)

    Avsyuk, Y.

    2007-12-01

    The present-day knowledge of the Earth and thorough description of the tidal force affecting the system Earth-Moon-Sun permits us to work out in detail a tidal evolution model. Thus we get a possibility to reconstruct global variations of the climate. The tidal evolution of natural processes on the Earth that has a huge satellite (the Moon mass is only 81 times less than the Earth mass) essentially differs from the evolution on a planet that has no satellite. There are some natural processes that are well-known in astrometry and geophysics but disregarded by experts in geodynamics and geotectonics. The movement of the rotation axis in the Earth's body is discovered more a century ago, but there is no a model explaining the mechanism of this process. Our predecessors emphasized importance of the discovery and suggested desire of such a model. G.H.Darwin in his comments on "Z-term" in the latitude variation wrote this movement could be due to alternate displacement of the Earth center. To explain the scale of that phenomena it is enough to adopt a displacement of the Earth center by twelve feet. A question is to the point is whether the Earth axis movement concerns with the Inner core (IC) displacements. There are some reasons testifying to forced movements of the IC. To understand the forcing influence one must not simplify the Earth's real orbital movement. In fact the system Earth-Moon rotates around the Sun with the period of year. The ecliptic is a plane containing the orbit of the Earth and the Moon mass center (barycenter). The Sun attraction is balanced dynamically in the barycenter but not in the Earth center. As a result, the Earth rotates just as the Moon round the barycenter with the period of the Moon month, and therefore the IC is subjected to a variable tidal force (1910). Newton in Append. XXV, problem VI, underlined that inasmuch as the Earth and the Moon rotate round their common mass center, the Earth movement is disturbed with similar forces

  6. A Development of the astronomical teaching materials which raise a student's time and and space concept by using of movement of the Moon, the Earth and the Sun

    NASA Astrophysics Data System (ADS)

    Taketa, I.; Matsumoto, I.

    2013-12-01

    In recent years, such as a return of the asteroid probe in 2010 "Hayabusa", a gold ring solar eclipse in 2012, and solar Face passage of Venus in 2012, there were many astronomical phenomena which pull a not only child but also citizen's interest, and they were greatly reported by the media in Japan. Thus, it is thought that the interest and concern about the universe of a child and a citizen are increasing. However, the earth science contents of a subject, such as the universe in school education are fields that it make comparatively poor at a teacher. So, this research aimed at the Development of the new space education teaching material which is easy to treat the teacher who has consciousness weak to the astronomical field at schools, and raise a child's time and space concepts. We did this research using the following Methods. 1) We carried out the questionnaire to the primary teacher of the Matsue city, and performed the opinion poll to a teacher's astronomical field. 2) We considered the subject on the education of the astronomical teaching materials used now. 3) As mentioned above 1) and 2), We developed the teaching materials which the waxing and waning of the moon based on the acquired content.

  7. Pipes to the earth subsurface: The role of atmospheric conditions in driving air movement along a borehole connecting land surface and an underground cavity

    NASA Astrophysics Data System (ADS)

    Weisbrod, Noam; Levintal, Elad; Lensky, Nadav G.; Mushkin, Amit; Dragila, Maria I.

    2017-04-01

    Understanding air dynamics in underground cavities (e.g., caves, underground storage structures, quarries, tunnels, etc.) and different types of boreholes is of great significance for the exploration of gas transport at the earth-atmosphere interface. Here, we investigated the role of atmospheric conditions on air transport inside a borehole. Two different geometries were explored in the field: a 27-m deep shaft connected to an underground large cavity and the same shaft after being disconnected from the underground cavity. The observation setup included a standard meteorological station located above the borehole and temperature and relative humidity sensors along the borehole. Absolute humidity, calculated from the measured temperature and relative humidity, was validated as a robust marker for assessing air transport inside the two shaft geometries examined. In both cases, air inflow and outflow at depths of 12 and 27 m was found to be related to changes in barometric pressure regardless of temperature instability (thermal-induced convection) or wind velocity (wind-induced convection). In contrast, these convective fluxes were found to be significant parameters driving air flow in the upper few meters. A newly developed conceptual model is presented to examine the induced airflow in both shaft geometries with the goal of improving our understanding of gas transport and its dependence on barometric pressure changes.

  8. About well-posed definition of geophysical fields'

    NASA Astrophysics Data System (ADS)

    Ermokhine, Konstantin; Zhdanova, Ludmila; Litvinova, Tamara

    2013-04-01

    We introduce a new approach to the downward continuation of geophysical fields based on approximation of observed data by continued fractions. Key Words: downward continuation, continued fraction, Viskovatov's algorithm. Many papers in geophysics are devoted to the downward continuation of geophysical fields from the earth surface to the lower halfspace. Known obstacle for the method practical use is a field's breaking-down phenomenon near the pole closest to the earth surface. It is explained by the discrepancy of the studied fields' mathematical description: linear presentation of the field in the polynomial form, Taylor or Fourier series, leads to essential and unremovable instability of the inverse problem since the field with specific features in the form of poles in the lower halfspace principally can't be adequately described by the linear construction. Field description by the rational fractions is closer to reality. In this case the presence of function's poles in the lower halfspace corresponds adequately to the denominator zeros. Method proposed below is based on the continued fractions. Let's consider the function measured along the profile and represented it in the form of the Tchebishev series (preliminary reducing the argument to the interval [-1, 1]): There are many variants of power series' presentation by continued fractions. The areas of series and corresponding continued fraction's convergence may differ essentially. As investigations have shown, the most suitable mathematical construction for geophysical fields' continuation is so called general C-fraction: where ( , z designates the depth) For construction of C-fraction corresponding to power series exists a rather effective and stable Viskovatov's algorithm (Viskovatov B. "De la methode generale pour reduire toutes sortes des quantitees en fraction continues". Memoires de l' Academie Imperiale des Sciences de St. Petersburg, 1, 1805). A fundamentally new algorithm for Downward Continuation

  9. Movement - uncontrollable

    MedlinePlus

    ... peripheral nervous system References Jankovic J, Lang AE. Movement disorders: diagnosis and assessment. In: Daroff RB, Fenichel GM, ... Elsevier Saunders; 2012:chap 21. Lang AE. Other movement disorders. In: Goldman L, Schafer AI, eds. Goldman's Cecil ...

  10. Movement - uncoordinated

    MedlinePlus

    ... Loss of coordination; Coordination impairment; Ataxia; Clumsiness; Uncoordinated movement ... Smooth graceful movement requires a balance between different muscle groups. A part of the brain called the cerebellum manages this balance.

  11. The Global Geophysical Fluids Center of IERS (and its Special Bureau for Mantle)

    NASA Technical Reports Server (NTRS)

    Chao, Benjamin F.

    2002-01-01

    The Global Geophysical Fluids Center (GGFC) was established by the International Earth Rotation Service (IERS) on IERS's 10th anniversary day January 1, 1998, in an effort to expand IERS's services to the scientific community. Under the GGFC, eight Special Bureaus (SB) have been selected, each to be responsible for research and data service activities pertaining to mass transports and related geophysical processes in specific components of the Earth system, or "global geophysical fluids," including the atmosphere, oceans, solid Earth, core, and geophysical processes of gravity, loading, tides and hydrological cycles. GGFC and the SBs have the responsibility of supporting, facilitating, and providing services to the worldwide research community, in areas related to the variations in Earth rotation, gravity field and geocenter that are caused by mass transport in the global geophysical fluids. These minute variations have been observed by various space geodetic techniques, as effective remote sensing tools, with ever increasing precision/accuracy and temporal/spatial resolution. The GGFC and SBs have organized dedicated workshops and special sessions at international conferences, published articles, and held regular business meetings. The SBs also maintain individual website for data services and information exchanges. See URL . In particular, the SB for Mantle focuses on large-scale mass redistributions that occur in the mantle in association with various dynamic processes, including seismic activities, the post-glacial rebound, and mantle convections.

  12. The Global Geophysical Fluids Center of IERS (and its Special Bureau for Mantle)

    NASA Astrophysics Data System (ADS)

    Chao, B. F.

    2002-12-01

    The Global Geophysical Fluids Center (GGFC) was established by the International Earth Rotation Service (IERS) on IERS's 10th anniversary day January 1, 1998, in an effort to expand IERS's services to the scientific community. Under the GGFC, eight Special Bureaus (SB) have been selected, each to be responsible for research and data service activities pertaining to mass transports and related geophysical processes in specific components of the Earth system, or "global geophysical fluids," including the atmosphere, oceans, solid Earth, core, and geophysical processes of gravity, loading, tides and hydrological cycles. GGFC and the SBs have the responsibility of supporting, facilitating, and providing services to the worldwide research community, in areas related to the variations in Earth rotation, gravity field and geocenter that are caused by mass transport in the global geophysical fluids. These minute variations have been observed by various space geodetic techniques, as effective remote sensing tools, with ever increasing precision/accuracy and temporal/spatial resolution. The GGFC and SBs have organized dedicated workshops and special sessions at international conferences, published articles, and held regular business meetings. The SBs maintain individual website for data services and information exchanges. See URL bowie.gsfc.nasa.gov/ggfc/. In particular, the SB for Mantle focuses on large-scale mass redistributions that occur in the mantle in association with various dynamic processes, including seismic activities, the post-glacial rebound, and mantle convections.

  13. The Global Geophysical Fluids Center of IERS (and its Special Bureau for Mantle)

    NASA Technical Reports Server (NTRS)

    Chao, Benjamin F.

    2002-01-01

    The Global Geophysical Fluids Center (GGFC) was established by the International Earth Rotation Service (IERS) on IERS's 10th anniversary day January 1, 1998, in an effort to expand IERS's services to the scientific community. Under the GGFC, eight Special Bureaus (SB) have been selected, each to be responsible for research and data service activities pertaining to mass transports and related geophysical processes in specific components of the Earth system, or "global geophysical fluids," including the atmosphere, oceans, solid Earth, core, and geophysical processes of gravity, loading, tides and hydrological cycles. GGFC and the SBs have the responsibility of supporting, facilitating, and providing services to the worldwide research community, in areas related to the variations in Earth rotation, gravity field and geocenter that are caused by mass transport in the global geophysical fluids. These minute variations have been observed by various space geodetic techniques, as effective remote sensing tools, with ever increasing precision/accuracy and temporal/spatial resolution. The GGFC and SBs have organized dedicated workshops and special sessions at international conferences, published articles, and held regular business meetings. The SBs also maintain individual website for data services and information exchanges. See URL . In particular, the SB for Mantle focuses on large-scale mass redistributions that occur in the mantle in association with various dynamic processes, including seismic activities, the post-glacial rebound, and mantle convections.

  14. Satellite gravity gradient grids for geophysics.

    PubMed

    Bouman, Johannes; Ebbing, Jörg; Fuchs, Martin; Sebera, Josef; Lieb, Verena; Szwillus, Wolfgang; Haagmans, Roger; Novak, Pavel

    2016-02-11

    The Gravity field and steady-state Ocean Circulation Explorer (GOCE) satellite aimed at determining the Earth's mean gravity field. GOCE delivered gravity gradients containing directional information, which are complicated to use because of their error characteristics and because they are given in a rotating instrument frame indirectly related to the Earth. We compute gravity gradients in grids at 225 km and 255 km altitude above the reference ellipsoid corresponding to the GOCE nominal and lower orbit phases respectively, and find that the grids may contain additional high-frequency content compared with GOCE-based global models. We discuss the gradient sensitivity for crustal depth slices using a 3D lithospheric model of the North-East Atlantic region, which shows that the depth sensitivity differs from gradient to gradient. In addition, the relative signal power for the individual gradient component changes comparing the 225 km and 255 km grids, implying that using all components at different heights reduces parameter uncertainties in geophysical modelling. Furthermore, since gravity gradients contain complementary information to gravity, we foresee the use of the grids in a wide range of applications from lithospheric modelling to studies on dynamic topography, and glacial isostatic adjustment, to bedrock geometry determination under ice sheets.

  15. Contemporary geophysics from Babylonian clay tablets

    NASA Astrophysics Data System (ADS)

    Morrison, L. V.; Stephenson, F. R.

    1997-01-01

    History and astronomy can be brought to bear on problems in contemporary geophysics. From seemingly crude ancient and medieval observations of eclipses, we show that variations in the length of the day can be traced back over the past 2500 years. The tidal torque exerted by the Moon (and, to a lesser extent, by the Sun) is the dominant mechanism in reducing the Earth's spin. It is known that by this mechanism, the length of the day is increasing by .- 1 + 2 3ms per century (mscy ). By analysing observations of eclipses, we find the actual measured change in the length of the day to be + 1.7mscy , from which we conclude that besides the tidal contribution, there is another long-term component acting to reduce - 1 the length of the day by- 0.6mscy . This component, which is thought to result from the decrease in the Earth's oblateness following the last Ice Age, is consistent with recent measurements made by artificial satellites. - 1

  16. Geophysical applications of satellite altimetry

    SciTech Connect

    Sandwell, D.T. )

    1991-01-01

    Publications related to geophysical applications of Seasat and Geosat altimetry are reviewed for the period 1987-1990. Problems discussed include geoid and gravity errors, regional geoid heights and gravity anomalies, local gravity field/flexure, plate tectonics, and gridded geoid heights/gravity anomalies. 99 refs.

  17. BROADBAND DIGITAL GEOPHYSICAL TELEMETRY SYSTEM.

    USGS Publications Warehouse

    Seeley, Robert L.; Daniels, Jeffrey J.

    1984-01-01

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

  18. Precession, Nutation and Wobble of the Earth

    NASA Astrophysics Data System (ADS)

    Dehant, V.; Mathews, P. M.

    2015-04-01

    Covering both astronomical and geophysical perspectives, this book describes changes in the Earth's orientation, specifically precession and nutation, and how they are observed and computed in terms of tidal forcing and models of the Earth's interior. Following an introduction to key concepts and elementary geodetic theory, the book describes how precise measurements of the Earth's orientation are made using observations of extra-galactic radio-sources by Very Long Baseline Interferometry techniques. It demonstrates how models are used to accurately pinpoint the location and orientation of the Earth with reference to the stars and how to determine variations in its rotation speed. A theoretical framework is also presented that describes the role played by the structure and properties of the Earth's deep interior. Incorporating suggestions for future developments in nutation theory for the next generation models, this book is ideal for advanced-level students and researche! rs in solid Earth geophysics, planetary science and astronomy.

  19. News and Views: CSR: the devil will be in the detail; MPs invite researchers to show off success; Earthquake movies reveal ground movements

    NASA Astrophysics Data System (ADS)

    2010-12-01

    The UK Government's Comprehensive Spending Review set out a distinctly tighter budget all round in October, but science funding as a whole was not as badly cut as some had feared. What this means for astronomy, planetary science and geophysics remains to be seen, as individual research council allocations have yet to be agreed. Early-career researchers with results to shout about have the opportunity to display and discuss their work at the House of Commons next year, as part of the SET for Britain event on 14 March. Seismology took a great step forward when international cooperation at the time of International Geophysical Year 1957/8 meant that earth movements resulting from quakes could be compared worldwide.

  20. Sulfur Earth

    NASA Astrophysics Data System (ADS)

    de Jong, B. H.

    2007-12-01

    Variations in surface tension affect the buoyancy of objects floating in a liquid. Thus an object floating in water will sink deeper in the presence of dishwater fluid. This is a very minor but measurable effect. It causes for instance ducks to drown in aqueous solutions with added surfactant. The surface tension of liquid iron is very strongly affected by the presence of sulfur which acts as a surfactant in this system varying between 1.9 and 0.4 N/m at 10 mass percent Sulfur (Lee & Morita (2002), This last value is inferred to be the maximum value for Sulfur inferred to be present in the liquid outer core. Venting of Sulfur from the liquid core manifests itself on the Earth surface by the 105 to 106 ton of sulfur vented into the atmosphere annually (Wedepohl, 1984). Inspection of surface Sulfur emission indicates that venting is non-homogeneously distributed over the Earth's surface. The implication of such large variation in surface tension in the liquid outer core are that at locally low Sulfur concentration, the liquid outer core does not wet the predominantly MgSiO3 matrix with which it is in contact. However at a local high in Sulfur, the liquid outer core wets this matrix which in the fluid state has a surface tension of 0.4 N/m (Bansal & Doremus, 1986), couples with it, and causes it to sink. This differential and diapiric movement is transmitted through the essentially brittle mantle (1024 Pa.s, Lambeck & Johnson, 1998; the maximum value for ice being about 1030 Pa.s at 0 K, in all likely hood representing an upper bound of viscosity for all materials) and manifests itself on the surface by the roughly 20 km differentiation, about 0.1 % of the total mantle thickness, between topographical heights and lows with concomitant lateral movement in the crust and upper mantle resulting in thin skin tectonics. The brittle nature of the medium though which this movement is transmitted suggests that the extremes in topography of the D" layer are similar in range to

  1. Studies of earth simulation experiments

    NASA Technical Reports Server (NTRS)

    Hart, J. E.

    1976-01-01

    The low gravity environment of earth orbit offers the potential for performing experiments involving baroclinic Geophysical Fluid Dynamics (GFD) on spherical surfaces. These experiments in turn have the potential for providing deeper understanding of large scale planetary and solar circulations. However, to perform these experiments, one requires an experimental technique whereby a radially directed body force can be generated to simulate a radial gravitational force field. One viable technique is the use of dielectric fluids with temperature dependent dielectric permittivity in a radially directed electric field. Application of the Boussinesq approximation to the equations of motion for this system and restrictions on the size of certain electrodynamic terms in the energy equations yields a set of equations which are analogous to the equations of motions of geophysical systems like the earth's atmosphere on term by term basis. The theoretical design of GFD experiments for performance in earth orbit are described along with results of preliminary tests of a prototype.

  2. The Geophysical Revolution in Geology.

    ERIC Educational Resources Information Center

    Smith, Peter J.

    1980-01-01

    Discussed is the physicists' impact on the revolution in the earth sciences particularly involving the overthrow of the fixist notions in geology. Topics discussed include the mobile earth, the route to plate tectonics, radiometric dating, the earth's magnetic field, ocean floor spreading plate boundaries, infiltration of physics into geology and…

  3. The Geophysical Revolution in Geology.

    ERIC Educational Resources Information Center

    Smith, Peter J.

    1980-01-01

    Discussed is the physicists' impact on the revolution in the earth sciences particularly involving the overthrow of the fixist notions in geology. Topics discussed include the mobile earth, the route to plate tectonics, radiometric dating, the earth's magnetic field, ocean floor spreading plate boundaries, infiltration of physics into geology and…

  4. Radar interferometry and its application to changes in the Earth's surface

    NASA Astrophysics Data System (ADS)

    Massonnet, Didier; Feigl, Kurt L.

    1998-11-01

    Geophysical applications of radar interferometry to measure changes in the Earth's surface have exploded in the early 1990s. This new geodetic technique calculates the interference pattern caused by the difference in phase between two images acquired by a spaceborne synthetic aperture radar at two distinct times. The resulting interferogram is a contour map of the change in distance between the ground and the radar instrument. These maps provide an unsurpassed spatial sampling density (˜100 pixels km-2), a competitive precision (˜1 cm), and a useful observation cadence (1 pass month-1). They record movements in the crust, perturbations in the atmosphere, dielectric modifications in the soil, and relief in the topography. They are also sensitive to technical effects, such as relative variations in the radar's trajectory or variations in its frequency standard. We describe how all these phenomena contribute to an interferogram. Then a practical summary explains the techniques for calculating and manipulating interferograms from various radar instruments, including the four satellites currently in orbit: ERS-1, ERS-2, JERS-1, and RADARSAT. The next chapter suggests some guidelines for interpreting an interferogram as a geophysical measurement: respecting the limits of the technique, assessing its uncertainty, recognizing artifacts, and discriminating different types of signal. We then review the geophysical applications published to date, most of which study deformation related to earthquakes, volcanoes, and glaciers using ERS-1 data. We also show examples of monitoring natural hazards and environmental alterations related to landslides, subsidence, and agriculture. In addition, we consider subtler geophysical signals such as postseismic relaxation, tidal loading of coastal areas, and interseismic strain accumulation. We conclude with our perspectives on the future of radar interferometry. The objective of the review is for the reader to develop the physical

  5. Forward modeling of geophysical electromagnetic methods using Comsol

    NASA Astrophysics Data System (ADS)

    Butler, S. L.; Zhang, Z.

    2016-02-01

    In geophysical electromagnetic methods, time-varying magnetic fields are measured at Earth's surface that are produced by electrical currents inside the Earth in order to constrain subsurface conductivity and geological structure. These methods are widely used for mineral exploration and environmental investigations, and are increasingly being used in hydrocarbon exploration as well. Forward modeling of exploration geophysics methods is useful for the purpose of survey planning, for understanding the method, especially for students, and as part of an iteration process in inverting measured data. Modeling electromagnetic methods remains an area of active research. In most geophysical methods, the electromagnetic frequency is sufficiently low that the wavelength of the radiation is much larger than the area of interest. As such, the quasi-static approximation is valid. Comsol Multiphysics' AC/DC module solves Maxwell's equations in the quasi-static approximation and in this contribution, we will show examples of its use in modeling magnetometric resistivity (MMR), very low frequency (VLF) techniques, as well as frequency and time-domain induction-based electromagnetic techniques. Solutions are compared with benchmarks from the literature.

  6. Earth Sciences annual report, 1987

    SciTech Connect

    Younker, L.W.; Donohue, M.L.; Peterson, S.J.

    1988-12-01

    The Earth Sciences Department at Lawrence Livermore National Laboratory conducts work in support of the Laboratory's energy, defense, and research programs. The Department is organized into ten groups. Five of these -- Nuclear Waste Management, Fossil Energy, Containment, Verification, and Research -- represent major programmatic activities within the Department. Five others -- Experimental Geophysics, Geomechanics, Geology/Geological Engineering, Geochemistry, and Seismology/Applied Geophysics -- are major disciplinary areas that support these and other laboratory programs. This report summarizes work carried out in 1987 by each group and contains a bibliography of their 1987 publications.

  7. Geophysical Institute. Biennial report, 1993-1994

    SciTech Connect

    1996-01-01

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

  8. A survey of the theory of the Earth's rotation

    NASA Technical Reports Server (NTRS)

    Cannon, W. H.

    1981-01-01

    The theory of the Earth's rotation and the geophysical phenomena affecting it is examined. First principles are reviewed and the problem of polar motion and UT1 variations is formulated in considerable generality and detail. The effects of Earth deformations and the solid Earth tides are analyzed.

  9. A Unified Global Reference Frame of Vertical Crustal Movements by Satellite Laser Ranging.

    PubMed

    Zhu, Xinhui; Wang, Ren; Sun, Fuping; Wang, Jinling

    2016-02-08

    Crustal movement is one of the main factors influencing the change of the Earth system, especially in its vertical direction, which affects people's daily life through the frequent occurrence of earthquakes, geological disasters, and so on. In order to get a better study and application of the vertical crustal movement,as well as its changes, the foundation and prerequisite areto devise and establish its reference frame; especially, a unified global reference frame is required. Since SLR (satellite laser ranging) is one of the most accurate space techniques for monitoring geocentric motion and can directly measure the ground station's geocentric coordinates and velocities relative to the centre of the Earth's mass, we proposed to take the vertical velocity of the SLR technique in the ITRF2008 framework as the reference frame of vertical crustal motion, which we defined as the SLR vertical reference frame (SVRF). The systematic bias between other velocity fields and the SVRF was resolved by using the GPS (Global Positioning System) and VLBI (very long baseline interferometry) velocity observations, and the unity of other velocity fields and SVRF was realized,as well. The results show that it is feasible and suitable to take the SVRF as a reference frame, which has both geophysical meanings and geodetic observations, so we recommend taking the SLR vertical velocity under ITRF2008 as the global reference frame of vertical crustal movement.

  10. The Emergence of Geophysics in Nineteenth Century Britain.

    NASA Astrophysics Data System (ADS)

    Kushner, David S.

    1990-01-01

    Three central interdisciplinary problems were crucial to the coalescence of a nascent community of scientists in Victorian Britain that was concerned specifically with questions about the nature and history of the earth as a physical body. These were (1) the structure of the earth and the thickness of its crust, (2) the age of the earth, and (3) the astronomical and physical causes of glacial epochs, or ice ages. This thesis concentrates on a particular interdisciplinary approach to these problems that explicitly sought to apply the techniques and methods of mathematical physics to the concerns of geology. The result was a new strand of applied mathematics and physics of the earth that was denominated 'physical geology' or 'terrestrial physics,' and eventually 'geophysics.' The thesis analyzes the mathematical foundations of this new strand and its evolving relationship with the parent disciplines, culminating in the transformation of the new field in the hands of Sir George Darwin, son of Charles, through his own brand of applied mathematics. The central historiographical aim is to analyze the dynamics of controversy and its role in the formation of the new discipline of geophysics. The origins of the field are traced to the researches of William Hopkins (c. 1840) on the phenomenon of precession to determine the thickness of the earth's crust. These are followed through to the 1860s research program of William Thomson (later Lord Kelvin) in terrestrial physics, wherein various concerns were tied together, notably the effective tidal rigidity of the earth and arguments to limit the earth's age, especially on the basis of tidal retardation. George Darwin's mathematical program, sparked by efforts to use polar wandering to explain glacial epochs, elaborated an entire theory of tidal evolution that explained the earth's physical history, including the obliquity of the ecliptic and the fissipartition of the moon. By the mid-1880s Darwin had bound together all three of

  11. Geophysical monitoring of a field-scale biostimulation pilot project

    USGS Publications Warehouse

    Lane, J.W.; Day-Lewis, F. D.; Casey, C.C.

    2006-01-01

    The USGS conducted a geophysical investigation in support of a U.S. Naval Facilities Engineering Command, Southern Division field-scale biostimulation pilot project at Anoka County Riverfront Park (ACP), downgradient of the Naval Industrial Reserve Ordnance Plant, Fridley, Minnesota. The goal of the pilot project is to evaluate subsurface injection of vegetable oil emulsion (VOE) to stimulate microbial degradation of chlorinated hydrocarbons. To monitor the emplacement and movement of the VOE and changes in water chemistry resulting from VOE dissolution and/or enhanced biological activity, the USGS acquired cross-hole radar zero-offset profiles, traveltime tomograms, and borehole geophysical logs during five site visits over 1.5 years. Analysis of pre- and postinjection data sets using petrophysical models developed to estimate VOE saturation and changes in total dissolved solids provides insights into the spatial and temporal distribution of VOE and ground water with altered chemistry. Radar slowness-difference tomograms and zero-offset slowness profiles indicate that the VOE remained close to the injection wells, whereas radar attenuation profiles and electromagnetic induction logs indicate that bulk electrical conductivity increased downgradient of the injection zone, diagnostic of changing water chemistry. Geophysical logs indicate that some screened intervals were located above or below zones of elevated dissolved solids; hence, the geophysical data provide a broader context for interpretation of water samples and evaluation of the biostimulation effort. Our results include (1) demonstration of field and data analysis methods for geophysical monitoring of VOE biostimulation and (2) site-specific insights into the spatial and temporal distributions of VOE at the ACP. ?? 2006 National Ground Water Association.

  12. Geophysical monitoring of a field-scale biostimulation pilot project.

    PubMed

    Lane, John W; Day-Lewis, Frederick D; Casey, Clifton C

    2006-01-01

    The USGS conducted a geophysical investigation in support of a U.S. Naval Facilities Engineering Command, Southern Division field-scale biostimulation pilot project at Anoka County Riverfront Park (ACP), down-gradient of the Naval Industrial Reserve Ordnance Plant, Fridley, Minnesota. The goal of the pilot project is to evaluate subsurface injection of vegetable oil emulsion (VOE) to stimulate microbial degradation of chlorinated hydrocarbons. To monitor the emplacement and movement of the VOE and changes in water chemistry resulting from VOE dissolution and/or enhanced biological activity, the USGS acquired cross-hole radar zero-offset profiles, travel-time tomograms, and borehole geophysical logs during five site visits over 1.5 years. Analysis of pre- and postinjection data sets using petrophysical models developed to estimate VOE saturation and changes in total dissolved solids provides insights into the spatial and temporal distribution of VOE and ground water with altered chemistry. Radar slowness-difference tomograms and zero-offset slowness profiles indicate that the VOE remained close to the injection wells, whereas radar attenuation profiles and electromagnetic induction logs indicate that bulk electrical conductivity increased down-gradient of the injection zone, diagnostic of changing water chemistry. Geophysical logs indicate that some screened intervals were located above or below zones of elevated dissolved solids; hence, the geophysical data provide a broader context for interpretation of water samples and evaluation of the biostimulation effort. Our results include (1) demonstration of field and data analysis methods for geophysical monitoring of VOE biostimulation and (2) site-specific insights into the spatial and temporal distributions of VOE at the ACP.

  13. Multidisciplinary Geophysical Study of the Earth’s Upper Structure.

    DTIC Science & Technology

    1988-12-27

    Tectonic Framework of southern New England and eastern New York, in. Kay, M., ed.. North Atlantic Geology and Continental Drift: American...reflection lines in the onshore and offshore portions of New England; and (3) by analysis of the geology of the region in the light of data from our...magnetic observatory installations and VLF meter, and analysis of existing aeromagnetic maps, suggest that major fault zones in eastern MA

  14. Satellite-tracking and earth-dynamics research programs

    NASA Technical Reports Server (NTRS)

    1975-01-01

    The activities and progress in the satellite tracking and earth dynamics research during the first half of calendar year 1975 are described. Satellite tracking network operations, satellite geodesy and geophysics programs, GEOS 3 project support, and atmospheric research are covered.

  15. Earth Sciences Division annual report 1981. [Lead abstract

    SciTech Connect

    Not Available

    1982-09-01

    Separate abstracts were prepared for the 59 papers of the 1981 annual report of the Earth Sciences Division at Lawrence Berkeley Laboratory. The general topics covered included nuclear waste isolation, geophysics and reservoir engineering, and geosciences. (KRM)

  16. Decadal variations in geophysical processes and asymmetries in the solar motion about the Solar System's barycentre

    NASA Astrophysics Data System (ADS)

    Sidorenkov, Nikolay; Wilson, Ian; Khlystov, Anatoly

    2010-05-01

    transferred to the Sun, and then back from it to all of the other planets. In other words, the Sun acts as a re-transmitter of gravitational motion over all of the solar system. 2) Activization of similar physical processes should take place simultaneously on all bodies in the solar system. Support for the last conclusion comes from the investigation of link between the most severe droughts on the Earth and powerful dust storms on Mars (Khlystov, 1995). Ian Wilson et al. (2008) presented evidence that claimed that changes in the Sun's equatorial rotation rate are synchronized with changes in the Sun's orbital motion about the barycentre of the Solar System. This paper showed that the recent maximum asymmetries in the Solar motion about the barycentre have occurred in the years 1865, 1900, 1934, 1970 and 2007. These years closely match the points of inflection in the Earth's LOD. In addition, Ian Wilson (Sidorenkov and Wilson 2009) shows that, from 1700 to 2000 A.D., on every occasion where the Sun has experienced a maximum in the asymmetry of its motion about the centre-of-mass of the Solar System, the Earth has also experienced a significant deviation in its rotation rate (i.e. LOD) from that expected from the long-term trends. This fact indicates that the changes in the Earth's rotation rate are synchronized with a phenomenon that is linked to the changes in the solar motion about the barycentre of the Solar System. Thus from the empirical data, we argue that there is compelling evidence to support the idea that these correlations are due to the shared motion of the Sun and Earth about the barycentre of the Solar System. We show that asymmetries in this shared motion lead to the decadal fluctuations in the climatologically and geophysical processes, including long term changes in the Earth's rotation rate. REFERENCES 1. Khlystov A.I., V.P.Dolgachev, and L.M.Domozhilova (1992). Barycentric movement of the Sun and Solar-Terrestrial relations, Biophysics, vol. 37, No 3, 455

  17. A spectral-geophysical approach for detecting pipeline leakage

    NASA Astrophysics Data System (ADS)

    van der Meijde, M.; van der Werff, H. M. A.; Jansma, P. F.; van der Meer, F. D.; Groothuis, G. J.

    2009-02-01

    Leakage of hydrocarbon has a large economic and environmental impact. Traditional methods for investigating leakage and resulting pollution, such as drilling, are destructive, time consuming and expensive. Remote sensing is an alternative that is non-destructive and has been been tested extensively for exploration of onshore hydrocarbon reservoirs and detection of hydrocarbons at the Earth's surface. In this research, a leaking pipeline is investigated through field reflectance spectrometry and the findings are validated with traditional drilling and geophysical measurements. The measurements show a significant increase of vegetation anomalies on the pipeline with respect to areas further away. The observed anomalies are positively related to hydrocarbon pollution through chemical analysis of drillings. Subsurface geophysical measurements show a large correlation with observed surface vegetation stress, enhancing the identification of hydrocarbon-related vegetation stress through spectroscopy.

  18. Alternative experiments using the geophysical fluid flow cell

    NASA Technical Reports Server (NTRS)

    Hart, J. E.

    1984-01-01

    This study addresses the possibility of doing large scale dynamics experiments using the Geophysical Fluid Flow Cell. In particular, cases where the forcing generates a statically stable stratification almost everywhere in the spherical shell are evaluated. This situation is typical of the Earth's atmosphere and oceans. By calculating the strongest meridional circulation expected in the spacelab experiments, and testing its stability using quasi-geostrophic stability theory, it is shown that strongly nonlinear baroclinic waves on a zonally symmetric modified thermal wind will not occur. The Geophysical Fluid Flow Cell does not have a deep enough fluid layer to permit useful studies of large scale planetary wave processes arising from instability. It is argued, however, that by introducing suitable meridional barriers, a significant contribution to the understanding of the oceanic thermocline problem could be made.

  19. Guided earth boring tool

    SciTech Connect

    Mc Donald, W.J.; Pittard, G.T.; Maurer, W.C.; Wasson, M.R.; Herben, W.C.

    1987-09-22

    A controllable tool for drilling holes in the earth is described comprising a hollow elongated rigid supporting drill pipe having a forward end for entering the earth, means supporting the drill pipe for earth boring or piercing movement, including means for moving the drill pipe longitudinally for penetrating the earth, the drill pipe moving means being constructed to permit addition and removal of supporting drill pipe during earth penetrating operation, a boring mole supported on the forward end of the hollow low drill pipe comprising a cylindrical housing supported on and open to the forward end of the drill pipe, a first means on the front end for applying a boring force to the soil comprising an anvil having a striking surface inside the housing and a boring surface outside the housing, a second means comprising a reciprocally movable hammer positioned in the housing to apply a percussive force to the anvil striking surface for transmitting a percussive force to the boring force applying means, and means permitting introduction of air pressure supplied through the hollow pipe into the housing for operating the hammer and for discharging spent air from the housing to the hole being bored, and the tool being operable to penetrate the earth upon longitudinal movement of the drill rod by the longitudinal rod moving means and operation of the mole by reciprocal movement of the hammer.

  20. A review of integrated geophysical investigations from archaeological and cultural sites under encroaching urbanisation in İzmir, Turkey

    NASA Astrophysics Data System (ADS)

    Drahor, Mahmut Göktuğ

    In the new millennium, globalisation, and with it urbanisation, has been expanding as a consequence of economic development throughout the world. Urbanisation is a major social problem, not only for developing countries but also for developed countries. Urbanisation also has a major impact on archaeological sites and cultural heritages in urbanised zones. Non-destructive investigation techniques, such as geophysics, which uses remote sensing, and is non-invasive, are of great importance in urban areas. We are now capable of solving urbanisation-related problems, and these techniques reduce the cost of projects at urbanised sites. Geophysics has increased the possibilities of new applications in determining intensive urbanisation effects in earth science. Geophysics deals with numerous physical variations such as electricity, electromagnetism, magnetics, acoustics, gravity and radioactivity. There are numerous ways geophysics can be applied in archaeological and cultural heritage studies. In addition the hazard mitigation, infrastructure investigation, waste management, water supply, urban gateways and other factors are documented by geophysics. In recent years, archaeological sites under the encroachment of urbanisation have been investigated on numerous occasions using non-invasive geophysical techniques, allowing parameters such as the depth, dimension and extension of targets to be clearly determined. The term “urban geophysics” has recently been seen in various references related to geophysics and other earth science studies. This study reviews the results of geophysical investigations carried out at important archaeological sites under encroaching urbanisation in the city of İzmir, Turkey.

  1. Smith heads Reviews of Geophysics

    NASA Astrophysics Data System (ADS)

    On January 1, Jim Smith began his term as editor-in-chief of Reviews of Geophysics. As editor-in-chief, he leads the board of editors in enhancing the journal's role as an integrating force in the geophysical sciences by providing timely overviews of current research and its trends. Smith is already beginning to fulfill the journal's role of providing review papers on topics of broad interest to Union members as well as the occasional definitive review paper on selected topics of narrower focus. Smith will lead the editorial board until December 31, 2000. Michael Coffey, Tommy Dickey, James Horwitz, Roelof Snieder, and Thomas Torgersen have been appointed as editors to serve with Smith. At least one more editor will be named to round out the disciplinary expertise on the board.

  2. New Geophysical Observatory in Uruguay

    NASA Astrophysics Data System (ADS)

    Sanchez Bettucci, L.; Nuñez, P.; Caraballo, R. R.; Ogando, R.

    2013-05-01

    In 2011 began the installation of the first geophysical observatory in Uruguay, with the aim of developing the Geosciences. The Astronomical and Geophysical Observatory Aiguá (OAGA) is located within the Cerro Catedral Tourist Farm (-34 ° 20 '0 .89 "S/-54 ° 42 '44.72" W, h: 270m). This has the distinction of being located in the center of the South Atlantic Magnetic Anomaly. Geologically is emplaced in a Neoproterozoic basement, in a region with scarce anthropogenic interference. The OAGA has, since 2012, with a GSM-90FD dIdD v7.0 and GSM-90F Overhauser, both of GEM Systems. In addition has a super-SID receiver provided by the Stanford University SOLAR Center, as a complement for educational purposes. Likewise the installation of a seismograph REF TEK-151-120A and VLF antenna is being done since the beginning of 2013.

  3. Geophysical fields of a megalopolis

    NASA Astrophysics Data System (ADS)

    Spivak, A. A.; Loktev, D. N.; Rybnov, Yu. S.; Soloviev, S. P.; Kharlamov, V. A.

    2016-12-01

    A description of the Center of Geophysical Monitoring for Systematic Investigation of Negative Consequences for the Human Environment and Infrastructure of the City of Moscow Resulting from Natural and Technogenic Factors, which is part of the Institute of Geosphere Dynamics of the Russian Academy of Sciences (IGD RAS), is presented. The results of synchronous observations of the seismic vibrations, electric and acoustic fields, and atmospheric meteoparameters performed at the Center and in the Mikhnevo Geophysical observatory of IGD RAS situated outside of the zone of the Moscow influence are examined. It is shown that the megalopolis influence consists of an increase in the amplitudes of the physical fields, a change in their spectral composition, and the violation of natural periodicities. A technogenic component that has a considerable impact on the natural physical processes in the surface atmosphere is an important factor that characterizes a megalopolis.

  4. Movement - uncontrolled or slow

    MedlinePlus

    Dystonia; Involuntary slow and twisting movements; Choreoathetosis; Leg and arm movements - uncontrollable; Arm and leg movements - uncontrollable; Slow involuntary movements of large muscle groups; Athetoid movements

  5. Geophysical Fluid Flow Cell Simulation

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Computer simulation of atmospheric flow corresponds well to imges taken during the second Geophysical Fluid Flow Cell (BFFC) mission. The top shows a view from the pole, while the bottom shows a view from the equator. Red corresponds to hot fluid rising while blue shows cold fluid falling. This simulation was developed by Anil Deane of the University of Maryland, College Park and Paul Fischer of Argorne National Laboratory. Credit: NASA/Goddard Space Flight Center

  6. Geophysical Plasmas and Atmospheric Modeling.

    DTIC Science & Technology

    1982-01-01

    0-AIII 639 SCIENCE APLICATIONS INC MCLEAN VA pis 4/1 GEOPHYSICAL. PLASMAS AND ATMOSPHERIC NOOCLIMG. (UI JAN 82 1 HMNh, J1 APIUZESE, S SNECH?. V CHAO...implied by delta functions. The eigenfunc- R 1_c 2 tion is continuous at each boundary and vanishes both at * web 2y V 4 -R1,)1r r<R4 , r -0 and r-R

  7. Europa Geophysical Explorer Mission Concept Studies

    NASA Astrophysics Data System (ADS)

    Green, J. R.; Abelson, R. D.; Smythe, W.; Spilker, T. R.; Shirley, J. H.

    2005-12-01

    The Strategic Road Map for Solar System Exploration recommended in May 2005 that NASA implement the Europa Geophysical Explorer (EGE) as a Flagship mission early in the next decade. This supported the recommendations of the National Research Council's Solar System Decadal Survey and the priorities of the Outer Planets Assessment Group (OPAG). The Europa Geophysical Explorer would: (1) Characterize tidal deformations of the surface of Europa and surface geology, to confirm the presence of a subsurface ocean; (2) Measure the three-dimensional structure and distribution of subsurface water; and (3) Determine surface composition from orbit, and potentially, prebiotic chemistry, in situ. As the next step in Europa exploration, EGE would build on previous Europa Orbiter concepts, for example, the original Europa Orbiter and the Jupiter Icy Moons Orbiter (JIMO). As well, a new set of draft Level One Requirements, provided by NASA sponsors, guided the concept development. These requirements included: (1) Earliest Launch: 2012; (2) Launch Vehicle: Delta IV Heavy or Atlas V; (3) Primary Propulsion: Chemical; (4) Power: Radioisotope Power System (RPS); (4) Orbital Mission: 30 days minimum to meet orbital science objectives; and (5) Earth Gravity Assists: Allowed. The previous studies and the new requirements contributed to the development of several scientifically capable and relatively mass-rich mission options. In particular, Earth-gravity assists (EGA) were allowed, resulting in an increased delivered mass. As well, there have been advances in radiation-hardened components and subsystems, due to the investments from the X-2000 technology program and JIMO. Finally, developments in radioisotope power systems (RPS) have added to the capability and reliability of the mission. Several potential mission options were explored using a variety of trade study methods, ranging from the work of the JPL EGE Team of scientists and engineers in partnership with the OPAG Europa Sub

  8. Geophysical monitoring technology for CO2 sequestration

    NASA Astrophysics Data System (ADS)

    Ma, Jin-Feng; Li, Lin; Wang, Hao-Fan; Tan, Ming-You; Cui, Shi-Ling; Zhang, Yun-Yin; Qu, Zhi-Peng; Jia, Ling-Yun; Zhang, Shu-Hai

    2016-06-01

    Geophysical techniques play key roles in the measuring, monitoring, and verifying the safety of CO2 sequestration and in identifying the efficiency of CO2-enhanced oil recovery. Although geophysical monitoring techniques for CO2 sequestration have grown out of conventional oil and gas geophysical exploration techniques, it takes a long time to conduct geophysical monitoring, and there are many barriers and challenges. In this paper, with the initial objective of performing CO2 sequestration, we studied the geophysical tasks associated with evaluating geological storage sites and monitoring CO2 sequestration. Based on our review of the scope of geophysical monitoring techniques and our experience in domestic and international carbon capture and sequestration projects, we analyzed the inherent difficulties and our experiences in geophysical monitoring techniques, especially, with respect to 4D seismic acquisition, processing, and interpretation.

  9. [Stereotypic movements].

    PubMed

    Fernández-Alvarez, E

    2003-02-01

    Stereotypic movements are repetitive patterns of movement with certain peculiar features that make them especially interesting. Their physiopathology and their relationship with the neurobehavioural disorders they are frequently associated with are unknown. In this paper our aim is to offer a simple analysis of their dominant characteristics, their differentiation from other processes and a hypothesis of the properties of stereotypic movements, which could all set the foundations for research work into their physiopathology.

  10. Rapid Geophysical Surveyor. Final report

    SciTech Connect

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

    1993-01-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2005-12-01

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

  12. Teaching Applied Geophysics at RTU: the Basics for a Fast, Green, Inexpensive Subground Investigation Method

    NASA Astrophysics Data System (ADS)

    Romagnoli, Francesco; Blumberga, Dagnija

    2010-01-01

    Geophysical methods are applied to determine a spatial model of the underground, to locate fault zones, to investigate the regional ground-water system, or to derive lithological parameters. In other words, applied geophysics provides the distribution of physical parameters of the subsurface through surveys at the earth's surface without destroying soil formations. In Latvia there are few expert companies of geophysics surveys. Thus, it is important that environmental experts have knowledge in this, and that Latvia, as a country, has access to international expertise. During the study introduced hereto we compared the geophysics course in the Riga Technical University (RTU) with similar courses in eight European universities and one Latvian university, gathering information through websites and/or personal contacts. We collected information about the duration of the courses, learning objectives, topics, teaching methods, credit points etc. As a result, proposals on how to improve the course in RTU were elaborated.

  13. Notes on interpretation of geophysical data over areas of mineralization in Afghanistan

    USGS Publications Warehouse

    Drenth, Benjamin J.

    2011-01-01

    Afghanistan has the potential to contain substantial metallic mineral resources. Although valuable mineral deposits have been identified, much of the country's potential remains unknown. Geophysical surveys, particularly those conducted from airborne platforms, are a well-accepted and cost-effective method for obtaining information on the geological setting of a given area. This report summarizes interpretive findings from various geophysical surveys over selected mineral targets in Afghanistan, highlighting what existing data tell us. These interpretations are mainly qualitative in nature, because of the low resolution of available geophysical data. Geophysical data and simple interpretations are included for these six areas and deposit types: (1) Aynak: Sedimentary-hosted copper; (2) Zarkashan: Porphyry copper; (3) Kundalan: Porphyry copper; (4) Dusar Shaida: Volcanic-hosted massive sulphide; (5) Khanneshin: Carbonatite-hosted rare earth element; and (6) Chagai Hills: Porphyry copper.

  14. Use of natural gamma-ray geophysical logs for SWAT water table parameter estimation

    USDA-ARS?s Scientific Manuscript database

    Preliminary soil and sub-soil hydraulic parameter estimates needed for SWAT simulations to determine sub-surface water movement were collected using downhole geophysical measurements. Gamma-ray logs are useful for distingishing sandstone from shales by measuring natural-gamma radiation emitted from ...

  15. Geophysical Model Research and Results

    SciTech Connect

    Pasyanos, M; Walter, W; Tkalcic, H; Franz, G; Flanagan, M

    2004-07-07

    Geophysical models constitute an important component of calibration for nuclear explosion monitoring. We will focus on four major topics: (1) a priori geophysical models, (2) surface wave models, (3) receiver function derived profiles, and (4) stochastic geophysical models. The first, a priori models, can be used to predict a host of geophysical measurements, such as body wave travel times, and can be derived from direct regional studies or even by geophysical analogy. Use of these models is particularly important in aseismic regions or regions without seismic stations, where data of direct measurements might not exist. Lawrence Livermore National Laboratory (LLNL) has developed the Western Eurasia and North Africa (WENA) model which has been evaluated using a number of data sets, including travel times, surface waves, receiver functions, and waveform analysis (Pasyanos et al., 2004). We have joined this model with our Yellow Sea - Korean Peninsula (YSKP) model and the Los Alamos National Laboratory (LANL) East Asia model to construct a model for all of Eurasia and North Africa. Secondly, we continue to improve upon our surface wave model by adding more paths. This has allowed us to expand the region to all of Eurasia and into Africa, increase the resolution of our model, and extend results to even shorter periods (7 sec). High-resolution models exist for the Middle East and the YSKP region. The surface wave results can be inverted either alone, or in conjunction with other data, to derive models of the crust and upper mantle structure. We are also using receiver functions, in joint inversions with the surface waves, to produce profiles directly under seismic stations throughout the region. In a collaborative project with Ammon, et al., they have been focusing on stations throughout western Eurasia and North Africa, while we have been focusing on LLNL deployments in the Middle East, including Kuwait, Jordan, and the United Arab Emirates. Finally, we have been

  16. Chloroplast movement.

    PubMed

    Wada, Masamitsu; Kagawa, Takatoshi; Sato, Yoshikatsu

    2003-01-01

    The study of chloroplast movement made a quantum leap at the beginning of the twenty-first century. Research based on reverse-genetic approaches using targeted mutants has brought new concepts to this field. One of the most exciting findings has been the discovery of photoreceptors for both accumulation and avoidance responses in Arabidopsis and in the fern Adiantum. Evidence for the adaptive advantage of chloroplast avoidance movements in plant survival has also been found. Additional discoveries include mechano-stress-induced chloroplast movement in ferns and mosses, and microtubule-mediated chloroplast movement in the moss Physcomitrella. The possible ecological significance of chloroplast movement is discussed in the final part of this review.

  17. Geophysical tomography. January 1976-July 1988 (Citations from the NTIS data base). Report for January 1976-July 1988

    SciTech Connect

    Not Available

    1988-07-01

    This bibliography contains citations concerning image reconstruction of geologic properties, internal geometry of rock masses, and mapping of fractures using geophysical tomography. Applications include site characterization, ground-water movement, structural geology, well logging, oil-field recovery processes, underground waste disposal, and geophysical surveys. The citations on techniques include algorithms and software to perform tomographic image reconstruction. (Contains 74 citations fully indexed and including a title list.)

  18. Satellite gravity gradient grids for geophysics

    NASA Astrophysics Data System (ADS)

    Bouman, Johannes; Ebbing, Jörg; Fuchs, Martin; Sebera, Josef; Lieb, Verena; Szwillus, Wolfgang; Haagmans, Roger; Novak, Pavel

    2016-02-01

    The Gravity field and steady-state Ocean Circulation Explorer (GOCE) satellite aimed at determining the Earth’s mean gravity field. GOCE delivered gravity gradients containing directional information, which are complicated to use because of their error characteristics and because they are given in a rotating instrument frame indirectly related to the Earth. We compute gravity gradients in grids at 225 km and 255 km altitude above the reference ellipsoid corresponding to the GOCE nominal and lower orbit phases respectively, and find that the grids may contain additional high-frequency content compared with GOCE-based global models. We discuss the gradient sensitivity for crustal depth slices using a 3D lithospheric model of the North-East Atlantic region, which shows that the depth sensitivity differs from gradient to gradient. In addition, the relative signal power for the individual gradient component changes comparing the 225 km and 255 km grids, implying that using all components at different heights reduces parameter uncertainties in geophysical modelling. Furthermore, since gravity gradients contain complementary information to gravity, we foresee the use of the grids in a wide range of applications from lithospheric modelling to studies on dynamic topography, and glacial isostatic adjustment, to bedrock geometry determination under ice sheets.

  19. Magnetotellurics as a multiscale geophysical exploration method

    NASA Astrophysics Data System (ADS)

    Carbonari, Rolando; D'Auria, Luca; Di Maio, Rosa; Petrillo, Zaccaria

    2016-04-01

    Magnetotellurics (MT) is a geophysical method based on the use of natural electromagnetic signals to define subsurface electrical resistivity structure through electromagnetic induction. MT waves are generated in the Earth's atmosphere and magnetosphere by a range of physical processes, such as magnetic storms, micropulsations, lightning activity. Since the underground MT wave propagation is of diffusive type, the longer is the wavelength (i.e. the lower the wave frequency) the deeper will be the propagation depth. Considering the frequency band commonly used in MT prospecting (10-4 Hz to 104 Hz), the investigation depth ranges from few hundred meters to hundreds of kilometers. This means that magnetotellurics is inherently a multiscale method and, thus, appropriate for applications at different scale ranging from aquifer system characterization to petroleum and geothermal research. In this perspective, the application of the Wavelet transform to the MT data analysis could represent an excellent tool to emphasize characteristics of the MT signal at different scales. In this note, the potentiality of such an approach is studied. In particular, we show that the use of a Discrete Wavelet (DW) decomposition of measured MT time-series data allows to retrieve robust information about the subsoil resistivity over a wide range of spatial (depth) scales, spanning up to 5 orders of magnitude. Furthermore, the application of DWs to MT data analysis has proven to be a flexible tool for advanced data processing (e.g. non-linear filtering, denoising and clustering).

  20. Satellite gravity gradient grids for geophysics

    PubMed Central

    Bouman, Johannes; Ebbing, Jörg; Fuchs, Martin; Sebera, Josef; Lieb, Verena; Szwillus, Wolfgang; Haagmans, Roger; Novak, Pavel

    2016-01-01

    The Gravity field and steady-state Ocean Circulation Explorer (GOCE) satellite aimed at determining the Earth’s mean gravity field. GOCE delivered gravity gradients containing directional information, which are complicated to use because of their error characteristics and because they are given in a rotating instrument frame indirectly related to the Earth. We compute gravity gradients in grids at 225 km and 255 km altitude above the reference ellipsoid corresponding to the GOCE nominal and lower orbit phases respectively, and find that the grids may contain additional high-frequency content compared with GOCE-based global models. We discuss the gradient sensitivity for crustal depth slices using a 3D lithospheric model of the North-East Atlantic region, which shows that the depth sensitivity differs from gradient to gradient. In addition, the relative signal power for the individual gradient component changes comparing the 225 km and 255 km grids, implying that using all components at different heights reduces parameter uncertainties in geophysical modelling. Furthermore, since gravity gradients contain complementary information to gravity, we foresee the use of the grids in a wide range of applications from lithospheric modelling to studies on dynamic topography, and glacial isostatic adjustment, to bedrock geometry determination under ice sheets. PMID:26864314

  1. Polar Misunderstandings: Earth's Dynamic Dynamo

    ERIC Educational Resources Information Center

    DiSpezio, Michael A.

    2011-01-01

    This article discusses the movement of Earth's north and south poles. The Earth's poles may be a bit more complex and dynamic than what many students and teachers believe. With better understanding, offer them up as a rich landscape for higher-level critical analysis and subject integration. Possible curriculum tie-ins include magnets, Earth…

  2. Polar Misunderstandings: Earth's Dynamic Dynamo

    ERIC Educational Resources Information Center

    DiSpezio, Michael A.

    2011-01-01

    This article discusses the movement of Earth's north and south poles. The Earth's poles may be a bit more complex and dynamic than what many students and teachers believe. With better understanding, offer them up as a rich landscape for higher-level critical analysis and subject integration. Possible curriculum tie-ins include magnets, Earth…

  3. Application of borehole geophysics to water-resources investigations

    USGS Publications Warehouse

    Keys, W.S.; MacCary, L.M.

    1971-01-01

    This manual is intended to be a guide for hydrologists using borehole geophysics in ground-water studies. The emphasis is on the application and interpretation of geophysical well logs, and not on the operation of a logger. It describes in detail those logging techniques that have been utilized within the Water Resources Division of the U.S. Geological Survey, and those used in petroleum investigations that have potential application to hydrologic problems. Most of the logs described can be made by commercial logging service companies, and many can be made with small water-well loggers. The general principles of each technique and the rules of log interpretation are the same, regardless of differences in instrumentation. Geophysical well logs can be interpreted to determine the lithology, geometry, resistivity, formation factor, bulk density, porosity, permeability, moisture content, and specific yield of water-bearing rocks, and to define the source, movement, and chemical and physical characteristics of ground water. Numerous examples of logs are used to illustrate applications and interpretation in various ground-water environments. The interrelations between various types of logs are emphasized, and the following aspects are described for each of the important logging techniques: Principles and applications, instrumentation, calibration and standardization, radius of investigation, and extraneous effects.

  4. ``An Earth-Shaking Experience''

    NASA Astrophysics Data System (ADS)

    Achenbach, Joel

    2005-03-01

    Last month's annual meeting of the American Geophysical Union in San Francisco drew an estimated 11,000 scientists, teachers, journalists and geophysics groupies. The schedule of talks could be found in a bound volume as thick as a phone book. You never see a geophysicist in ordinary life, but apparently the world is crawling with them. They came to talk about everything from the ozone layer to the big wad of iron at the center of the Earth. Also about other planets. And magnetic fields. Solar wind. Water on Mars. To be at this convention was to be immersed to the eyebrows in scientific knowledge. It is intellectually fashionable to fetishize the unknown, but at AGU, a person will get the opposite feeling-that science is a voracious, relentless and tireless enterprise, and that soon there may not remain on this Earth an unturned stone.

  5. Reports on crustal movements and deformations

    NASA Technical Reports Server (NTRS)

    Cohen, S. C.; Peck, T.

    1981-01-01

    Studies of tectonic plate motions, regional crustal deformations, strain accumulation and release, deformations associated with earthquakes and fault motion, and micro-plate motion, were collected and are summarized. To a limited extent, papers dealing with global models of current plate motions and crustal stress are included. The data base is restricted to articles appearing in reveiwed technical journals during the years 1970-1980. The major journals searched include: Journal of Geophysical Research (solid earth), Tectonophysics, Bulletin of the Seismological Society of America, Geological Society of America Bulletin, Geophysical Journal of the Royal Astronomical Society, and the Journal of Geology.

  6. Geophysical Model Applications for Monitoring

    SciTech Connect

    Pasyanos, M; Walter, W; Tkalcic, H; Franz, G; Gok, R; Rodgers, A

    2005-07-11

    Geophysical models constitute an important component of calibration for nuclear explosion monitoring. We will focus on four major topics and their applications: (1) surface wave models, (2) receiver function profiles, (3) regional tomography models, and (4) stochastic geophysical models. First, we continue to improve upon our surface wave model by adding more paths. This has allowed us to expand the region to all of Eurasia and into Africa, increase the resolution of our model, and extend results to even shorter periods (7 sec). High-resolution models exist for the Middle East and the YSKP region. The surface wave results can be inverted either alone, or in conjunction with other data, to derive models of the crust and upper mantle structure. One application of the group velocities is to construct phase-matched filters in combination with regional surface-wave magnitude formulas to improve the mb:Ms discriminant and extend it to smaller magnitude events. Next, we are using receiver functions, in joint inversions with the surface waves, to produce profiles directly under seismic stations throughout the region. In the past year, we have been focusing on deployments throughout the Middle East, including the Arabian Peninsula and Turkey. By assembling the results from many stations, we can see how regional seismic phases are affected by complicated upper mantle structure, including lithospheric thickness and anisotropy. The next geophysical model item, regional tomography models, can be used to predict regional travel times such as Pn and Sn. The times derived by the models can be used as a background model for empirical measurements or, where these don't exist, simply used as is. Finally, we have been exploring methodologies such as Markov Chain Monte Carlo (MCMC) to generate data-driven stochastic models. We have applied this technique to the YSKP region using surface wave dispersion data, body wave travel time data, receiver functions, and gravity data. The models

  7. The Earth System Model

    NASA Technical Reports Server (NTRS)

    Schoeberl, Mark; Rood, Richard B.; Hildebrand, Peter; Raymond, Carol

    2003-01-01

    The Earth System Model is the natural evolution of current climate models and will be the ultimate embodiment of our geophysical understanding of the planet. These models are constructed from components - atmosphere, ocean, ice, land, chemistry, solid earth, etc. models and merged together through a coupling program which is responsible for the exchange of data from the components. Climate models and future earth system models will have standardized modules, and these standards are now being developed by the ESMF project funded by NASA. The Earth System Model will have a variety of uses beyond climate prediction. The model can be used to build climate data records making it the core of an assimilation system, and it can be used in OSSE experiments to evaluate. The computing and storage requirements for the ESM appear to be daunting. However, the Japanese ES theoretical computing capability is already within 20% of the minimum requirements needed for some 2010 climate model applications. Thus it seems very possible that a focused effort to build an Earth System Model will achieve succcss.

  8. Earth's core iron

    NASA Astrophysics Data System (ADS)

    Geophysicist J. Michael Brown of Texas A & M University noted recently at the Spring AGU Meeting in Baltimore that the structure and phase of metallic iron at pressures of the earth's inner core (approximately 3.3 Mbar) could have great significance in defining geometrical aspects of the core itself. Brown worked at the Los Alamos Scientific Laboratory with R.B. McQueen to redetermine the phase relations of metallic iron in a series of new shock-wave experiments. They found the melting point of iron at conditions equal to those at the boundary of the earth's outer (liquid) and inner (solid) cores to be 6000°±500°C (Geophysical Research Letters, 7, 533-536, 1980).

  9. Bringing 3D Printing to Geophysical Science Education

    NASA Astrophysics Data System (ADS)

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

    2014-12-01

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

  10. Environmental and Engineering Geophysical University at SAGEEP 2008: Geophysical Instruction for Non-Geophysicists

    SciTech Connect

    Jeffrey G. Paine

    2009-03-13

    The Environmental and Engineering Geophysical Society (EEGS), a nonprofit professional organization, conducted an educational series of seminars at the Symposium on the Application of Geophysics to Engineering and Environmental Problems (SAGEEP) in Philadelphia in April 2008. The purpose of these seminars, conducted under the name Environmental and Engineering Geophysical University (EEGU) over three days in parallel with the regular SAGEEP technical sessions, was to introduce nontraditional geophysical conference attendees to the appropriate use of geophysics in environmental and engineering projects. Five half-day, classroom-style sessions were led by recognized experts in the application of seismic, electrical, gravity, magnetics, and ground-penetrating radar methods. Classroom sessions were intended to educate regulators, environmental program managers, consultants, and students who are new to near-surface geophysics or are interested in learning how to incorporate appropriate geophysical approaches into characterization or remediation programs or evaluate the suitability of geophysical methods for general classes of environmental or engineering problems.

  11. SURFACE GEOPHYSICAL EXPLORATION - COMPENDIUM DOCUMENT

    SciTech Connect

    RUCKER DF; MYERS DA

    2011-10-04

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

  12. Current Legislative Initiatives and Geophysics

    NASA Astrophysics Data System (ADS)

    Stephan, S. G.

    2002-05-01

    Geophysical research will be most effective in the fight against terrorism if it is done in cooperation with the expectations of local, state and federal policy makers. New tools to prevent, prepare for, and respond to acts of terrorism are coming from all fields, including geoscience. Globally, monitoring the land, oceans, atmosphere, and space for unusual and suspicious activities can help prevent terrorist acts. Closer to home, geoscience research is used to plan emergency transportation routes and identify infrastructure vulnerabilities. As important as it is for Congress and other policy makers to appreciate the promises and limitations of geophysical research, scientists need to be aware of legislative priorities and expectations. What does Congress expect from the geoscience community in the fight against terrorism and how well does reality meet these expectations? What tools do the 44 different federal agencies with stated Homeland Security missions need from geoscientists? I will address these questions with an overview of current legislative antiterrorism initiatives and policies that relate to the geoscience community.

  13. Application of borehole geophysics to fracture identification and characterization in low porosity limestones and dolostones

    SciTech Connect

    Haase, C.S.; King, H.L.

    1986-01-01

    Geophysical logging was conducted in exploratory core holes drilled for geohydrological investigations at three sites used for waste disposal on the US Department of Energy's Oak Ridge Reservation. Geophysical log response was calibrated to borehole geology using the drill core. Subsequently, the logs were used to identify fractures and fractured zones and to characterize the hydrologic activity of such zones. Results of the study were used to identify zones of ground water movement and to select targets for subsequent piezometer and monitoring well installation. Neutron porosity, long- and short-normal resistivity, and density logs exhibit anomalies only adjacent to pervasively fractured zones and rarely exhibit anomalies adjacent to individual fractures, suggesting that such logs have insufficient resolution to detect individual fractures. Spontaneous potential, single point resistance, acoustic velocity, and acoustic variable density logs, however, typically exhibit anomalies adjacent to both individual fractures and fracture zones. Correlation is excellent between fracture density logs prepared from the examination of drill core and fractures identified by the analysis of a suite of geophysical logs that have differing spatial resolution characteristics. Results of the study demonstrate the importance of (1) calibrating geophysical log response to drill core from a site, and (2) running a comprehensive suite of geophysical logs that can evaluate both large- and small-scale rock features. Once geophysical log responses to site-specific geological features have been established, logs provide a means of identifying fracture zones and discriminating between hydrologically active and inactive fracture zones. 9 figs.

  14. Lunar geophysics, geodesy, and dynamics

    NASA Technical Reports Server (NTRS)

    Williams, J. G.; Dickey, J. O.

    2002-01-01

    Experience with the dynamics and data analyses for earth and moon reveals both similarities and differences. Analysis of Lunar Laser Ranging (LLR) data provides information on the lunar orbit, rotation, solid-body tides, and retroreflector locations.

  15. Lunar geophysics, geodesy, and dynamics

    NASA Technical Reports Server (NTRS)

    Williams, J. G.; Dickey, J. O.

    2002-01-01

    Experience with the dynamics and data analyses for earth and moon reveals both similarities and differences. Analysis of Lunar Laser Ranging (LLR) data provides information on the lunar orbit, rotation, solid-body tides, and retroreflector locations.

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

    NASA Astrophysics Data System (ADS)

    Pandya, R. E.; Murray, D.

    2002-12-01

    heart of the VGEE is the visualization environment. The visualization environment is a customized version of the Integrated Data Viewer, or IDV, a platform-independent software package being developed by Unidata for display and analysis of geophysical data. In addition to the learner-centered functionality mentioned above, this environment allows the ability to locate and analyze remote data sets, including both archived and real-time data. As such, the tool represents a road toward creating a "data web" where educational users can browse and use data in a seamless way. While our discussion of the VGEE will highlight its use in specific curricula; we will point towards the development of the next generation data web in the Digital Library for Earth Science Education (DLESE). Our discussion will also summarize the data gathered while using the VGEE in an entry-level geoscience laboratory course.

  17. Early Earth

    NASA Astrophysics Data System (ADS)

    Brown, M.

    2015-05-01

    Earth has continents, subduction and mobile lid plate tectonics, but details of the early evolution are poorly understood. Here I summarize the Hadean-Archean record, review evidence for a hotter Earth and consider geodynamic models for early Earth.

  18. Airborne geophysical surveys over the eastern Adirondacks, New York State

    USGS Publications Warehouse

    Shah, Anjana K.

    2016-01-01

    Airborne geophysical surveys were conducted in the eastern Adirondacks from Dec. 7, 2015 - Dec. 21, 2015, by Goldak Airborne Surveys. The area was flown along a draped surface with a nominal survey height above ground of 200 meters. The flight line spacing was 250 meters for traverse lines and 2500 meters for control lines. Here we present downloadable magnetic and radiometric (gamma spectrometry) data from those surveys as image (Geotiff) and flight line data (csv format).BackgroundThe Eastern Adirondacks region was known for iron mining in the 1800's and 1900's but it also contains deposits of rare earth minerals. Rare earth minerals are used in advanced technology such as in cell phones, rechargeable batteries and super-magnets. In many areas rare earth minerals appear to be associated with iron ore.The surveys were flown in order to map geologic variations in three dimensions. Magnetic surveys measure subtle changes in Earth's magnetic field that reflect different types of buried rock, such as iron-rich ore bodies. Radiometric methods detect naturally occurring gamma particles. The energy spectra of these particles can be used to estimate relative amounts of potassium, uranium and thorium (also referred to as gamma ray spectrometry), which are sometimes associated with rare earth elements. Together, these data provide insights into the regional tectonic and magmatic history as well as mineral resources in the area.

  19. Press conference bring excitement of geophysical research to the public

    NASA Astrophysics Data System (ADS)

    Leifert, Harvey

    “A Flare to Remember.” “Starbucks for Starfish.” “Earth's Rotation Slows for El Niño.” What do these catchy headlines have in common? They all resulted from presentations at AGU's Spring Meeting in Boston, Mass. Yes, geophysical science can be big news when presented in a way that is interesting to general audiences.Proof? Well, the “Flare to Remember” headline (in the Dallas Morning News) reported the discovery, via the SOHO spacecraft, that a solar flare had produced, deep inside the Sun, seismic disturbances of a magnitude never experienced on Earth. Researchers Valentina Zharkova of Glasgow University and Alexander Kosovichev of Stanford gave media representatives a preview of their session, supported by visual aids, in the AGU press briefing room.

  20. SQUID use for Geophysics: finding billions of dollars

    NASA Astrophysics Data System (ADS)

    Foley, Catherine

    2014-03-01

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

  1. Geophysical Exploration Technologies for the Deep Lithosphere Research: An Education Materials for High School Students

    NASA Astrophysics Data System (ADS)

    Xu, H.; Xu, C.; Luo, S.; Chen, H.; Qin, R.

    2012-12-01

    The science of Geophysics applies the principles of physics to study of the earth. Geophysical exploration technologies include the earthquake seismology, the seismic reflection and refraction methods, the gravity method, the magnetic method and the magnetotelluric method, which are used to measure the interior material distribution, their structure and the tectonics in the lithosphere of the earth. Part of the research project in SinoProbe-02-06 is to develop suitable education materials for carton movies targeting the high school students and public. The carton movies include five parts. The first part includes the structures of the earth's interior and variation in their physical properties that include density, p-wave, s-wave and so on, which are the fundamentals of the geophysical exploration technologies. The second part includes the seismology that uses the propagation of elastic waves through the earth to study the structure and the material distribution of the earth interior. It can be divided into earthquake seismology and artifice seismics commonly using reflection and refraction. The third part includes the magnetic method. Earth's magnetic field (also known as the geomagnetic field)extends from the Earth's inner core to where it meets the solar wind, a stream of energetic particles emanating from the Sun. The aim of magnetic survey is to investigate subsurface geology on the basis of anomalies in the Earth's magnetic field resulting from the magnetic properties of the underlying rocks. The magnetic method in the lithosphere attempts to use magnetic disturbance to analyse the regional geological structure and the magnetic boundaries of the crust. The fourth part includes the gravity method. A gravity anomaly results from the inhomogeneous distribution of density of the Earth. Usually gravity anomalies contain superposed anomalies from several sources. The long wave length anomalies due to deep density contrasts are called regional anomalies. They are

  2. Earth Rotation Dynamics: Review and Prospects

    NASA Technical Reports Server (NTRS)

    Chao, Benjamin F.

    2004-01-01

    Modem space geodetic measurement of Earth rotation variations, particularly by means of the VLBI technique, has over the years allowed studies of Earth rotation dynamics to advance in ever-increasing precision, accuracy, and temporal resolution. A review will be presented on our understanding of the geophysical and climatic causes, or "excitations", for length-of-day change, polar motion, and nutations. These excitations sources come from mass transports that constantly take place in the Earth system comprised of the atmosphere, hydrosphere, cryosphere, lithosphere, mantle, and the cores. In this sense, together with other space geodetic measurements of time-variable gravity and geocenter motion, Earth rotation variations become a remote-sensing tool for the integral of all mass transports, providing valuable information about the latter on a wide range of spatial and temporal scales. Future prospects with respect to geophysical studies with even higher accuracy and resolution will be discussed.

  3. Earth Rotation Dynamics: Review and Prospects

    NASA Technical Reports Server (NTRS)

    Chao, Benjamin F.

    2004-01-01

    Modem space geodetic measurement of Earth rotation variations, particularly by means of the VLBI technique, has over the years allowed studies of Earth rotation dynamics to advance in ever-increasing precision, accuracy, and temporal resolution. A review will be presented on our understanding of the geophysical and climatic causes, or "excitations", for length-of-day change, polar motion, and nutations. These excitations sources come from mass transports that constantly take place in the Earth system comprised of the atmosphere, hydrosphere, cryosphere, lithosphere, mantle, and the cores. In this sense, together with other space geodetic measurements of time-variable gravity and geocenter motion, Earth rotation variations become a remote-sensing tool for the integral of all mass transports, providing valuable information about the latter on a wide range of spatial and temporal scales. Future prospects with respect to geophysical studies with even higher accuracy and resolution will be discussed.

  4. Defining the Moho: the Necessity of Combining Different Geophysical Observations

    NASA Astrophysics Data System (ADS)

    Liu, T.; TAO, K.; Ning, J.

    2013-12-01

    Although the crust was clearly defined as the uppermost layer of the solid earth and has been widely studied by geophysicists, the exact location of Moho---the interface between the crust and the mantle--is still far from clear, at least in some regions. The western part of the North China Craton, namely the Ordos Block, is one such region. In the past ten years, much evidence from receiver-function images has suggested that the Moho beneath Ordos is at ~ 40 km depth. However, a recent study using the newly developed Virtual Depth Seismic Sounding (VDSS) (Yu et al., EPSL, 2012), discovered that the Moho under Ordos is more likely to be at a ~ 60 km depth whereas the interface at ~ 40 km depth is better interpreted as an intra-crustal interface. This raises the question, which seismic method best defines the real Moho? To answer this question, in this study we stress the definition of the Moho as the interface between crustal rock and mantle rock rather than the seismic discontinuity with greatest velocity contrast near the earth surface. Using this re-definition of the Moho, we re-examined the geophysical observations that have been made in Ordos. We found that although the receiver-function method is powerful in imaging crustal and upper-mantle interfaces, it has the shortcoming that it is only sensitive to the S-wave velocity contrast across the interface. Therefore in some regions where the Moho does not have a sharp S-wave velocity contrast, for example in Ordos, the receiver-function image may give the wrong location of the Moho. In such situations, a comprehensive study combining different geophysical observations becomes necessary to determine the Moho. We have shown that VDSS is a very good supplement to the receiver-function technique because it is mainly sensitive to P-wave velocity contrast across the interface. With images provided by both receiver-function analysis and VDSS, we found that the discontinuity at ~60 km depth under Ordos is more likely to

  5. Earth Sciences Division annual report 1989

    SciTech Connect

    Not Available

    1990-06-01

    This Annual Report presents summaries of selected representative research activities from Lawrence Berkeley Laboratory grouped according to the principal disciplines of the Earth Sciences Division: Reservoir Engineering and Hydrology, Geology and Geochemistry, and Geophysics and Geomechanics. We are proud to be able to bring you this report, which we hope will convey not only a description of the Division's scientific activities but also a sense of the enthusiasm and excitement present today in the Earth Sciences.

  6. Earth's motions in pharaonic Egypt: Religious interpretations

    NASA Astrophysics Data System (ADS)

    Jambon, Emmanuel

    This paper will deal with the representations of the earth's movements in pharaonic Egypt. At first, testimonies of an ancient literary pattern, the "sky and earth" figure, will be observed, and then, the pictures where earth is represented "alone". We will explore the different ways the Egyptians depicted and interpreted this phenomena through various texts.

  7. Remote sensing-a geophysical perspective.

    USGS Publications Warehouse

    Watson, K.

    1985-01-01

    In this review of developments in the field of remote sensing from a geophysical perspective, the subject is limited to the electromagnetic spectrum from 0.4 mu m to 25cm. Three broad energy categories are covered: solar reflected, thermal infrared, and microwave.-from Authorremote sensing electromagnetic spectrum solar reflected thermal infrared microwave geophysics

  8. Agricultural Geophysics: Past, present, and future

    USDA-ARS?s Scientific Manuscript database

    Geophysical methods are becoming an increasingly valuable tool for agricultural applications. Agricultural geophysics investigations are commonly (although certainly not always) focused on delineating small- and/or large-scale objects/features within the soil profile (~ 0 to 2 m depth) over very lar...

  9. Successful educational geophysics field program expands

    NASA Astrophysics Data System (ADS)

    The Summer of Applied Geophysical Experience (SAGE), a program that gives students an opportunity to apply a variety of modern geophysical methods in a challenging geologic environment, has expanded.A 2-year grant awarded in 1993 by the National Science Foundation's Research Experiences for Undergraduate's (REU) initiative allowed the program to include fourteen U.S. undergraduate students last summer.

  10. Test plan for the Rapid Geophysical Surveyor

    SciTech Connect

    Roybal, L.G.

    1993-06-01

    This document describes the test plant for demonstrating and testing a set of optically pumped cesium-based total field magnetometers using the Rapid Geophysical Surveyor platform. The proposed testing will be used to assess the function of these magnetometers as deployed on the Rapid Geophysical Surveyor and evaluate the practical utility of high resolution magnetic data for supporting waste retrieval efforts.

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

    NASA Astrophysics Data System (ADS)

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

    2011-12-01

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

  12. Goddard Geophysical and Astronomical Observatory

    NASA Technical Reports Server (NTRS)

    Figueroa, Ricardo

    2013-01-01

    This report summarizes the technical parameters and the technical staff of the VLBI system at the fundamental station GGAO. It also gives an overview about the VLBI activities during the report year. The Goddard Geophysical and Astronomical Observatory (GGAO) consists of a 5-meter radio telescope for VLBI, a new 12-meter radio telescope for VLBI2010 development, a 1-meter reference antenna for microwave holography development, an SLR site that includes MOBLAS-7, the NGSLR development system, and a 48" telescope for developmental two-color Satellite Laser Ranging, a GPS timing and development lab, a DORIS system, meteorological sensors, and a hydrogen maser. In addition, we are a fiducial IGS site with several IGS/IGSX receivers. GGAO is located on the east coast of the United States in Maryland. It is approximately 15 miles NNE of Washington, D.C. in Greenbelt, Maryland.

  13. Satellite Relaying of Geophysical Data

    NASA Technical Reports Server (NTRS)

    Allenby, R. J.

    1977-01-01

    Data Collection Platforms (DCPs) for transmitting surface data to an orbiting satellite for relaying to a central data distribution center are being used in a number of geophysical applications. "Off-the-shelf" DCP's, transmitting through Landsat or GOES satellites, are fully capable of relaying data from low-data-rate instruments, such as tiltmeters or tide gauges. In cooperation with the Lamont-Doherty Geological Observatory, Goddard has successfully installed DCP systems on a tide gauge and tiltmeter array on Anegada, British Virgin Islands. Because of the high-data-rate requirements, a practical relay system capable of handling seismic information is not yet available. Such a system could become the basis of an operational hazard prediction system for reducing losses due to major natural catastrophies such as earthquakes, volcanic eruptions, landslides or tsunamis.

  14. Celebrating the physics in geophysics

    NASA Astrophysics Data System (ADS)

    Davis, Anthony B.; Sornette, Didier

    The United Nations' Educational, Scientific and Cultural Organization (UNESCO) declared 2005 the “World Year of Physics” in celebration of the centennial of Einstein's annus mirabilis when, as junior clerk at the Swiss Patent Office in Berne, he published three papers that changed physics forever by (1) introducing Special Relativity and demonstrating the equivalence of mass and energy (E = mc2), (2) explaining the photoelectric effect with Planck's then-still-new-and-controversial concept of light quanta (E = hv), and (3) investigating the macroscopic phenomenon of Brownian motion using Boltzmann's molecular dynamics (E = kT), still far from fully accepted at the time.The celebration of Einstein's work in physics inspires the reflection on the status of geophysics and its relationship with physics, in particular with respect to great discoveries.

  15. The measurement of Earth rotation on a deformable Earth

    NASA Technical Reports Server (NTRS)

    Cannon, W. H.

    1980-01-01

    Until recently, the methods of geodetic positioning on the Earth were limited to a precision of roughly one part in 10 to the 6th power. At this level of precision, the Earth can be regarded as a rigid body since the largest departure of the Earth from rigidity is manifested in the strains of the Earth tides which are of the order of one part in 10 to the 7th power. Long baseline interferometry is expected to routinely provide global positioning to a precision of one part in 10 to the 8th power or better. At this level of precision, all parts of the Earth's surface must be regarded as being, at least potentially, in continual motion relative to the geocenter as a result of a variety of geophysical effects. The general implications of this phenomenon for the theory of the Earth's rotation is discussed. Particular attention is given to the question of the measurement of the 'Earth's rotation vector' on a deformable Earth.

  16. Advances in borehole geophysics for hydrology

    SciTech Connect

    Nelson, P.H.

    1982-01-01

    Borehole geophysical methods provide vital subsurface information on rock properties, fluid movement, and the condition of engineered borehole structures. Within the first category, salient advances include the continuing improvement of the borehole televiewer, refinement of the electrical conductivity dipmeter for fracture characterization, and the development of a gigahertz-frequency electromagnetic propagation tool for water saturation measurements. The exploration of the rock mass between boreholes remains a challenging problem with high potential; promising methods are now incorporating high-density spatial sampling and sophisticated data processing. Flow-rate measurement methods appear adequate for all but low-flow situations. At low rates the tagging method seems the most attractive. The current exploitation of neutron-activation techniques for tagging means that the wellbore fluid itself is tagged, thereby eliminating the mixing of an alien fluid into the wellbore. Another method uses the acoustic noise generated by flow through constrictions and in and behind casing to detect and locate flaws in the production system. With the advent of field-recorded digital data, the interpretation of logs from sedimentary sequences is now reaching a sophisticated level with the aid of computer processing and the application of statistical methods. Lagging behind are interpretive schemes for the low-porosity, fracture-controlled igneous and metamorphic rocks encountered in the geothermal reservoirs and in potential waste-storage sites. Progress is being made on the general problem of fracture detection by use of electrical and acoustical techniques, but the reliable definition of permeability continues to be an elusive goal.

  17. Application of internal gravitational field equations to geophysical measurement of G

    NASA Technical Reports Server (NTRS)

    Rubincam, David Parry; Chao, B. Fong; Schatten, Kenneth H.

    1989-01-01

    The spherical harmonic equation for the gravitational potential inside the earth is presented. The equation satisfies Poisson's equation and converges uniformly. It obviates the need for downward continuation of the exterior potential with its attendant convergence difficulties but of course requires some knowledge of the earth's density distribution. The equation is used to derive the general expression for the geophysical measurement of the gravitational constant G made inside the earth, such as in boreholes and mine shafts. Numerical evidence is also presented to show that the long- to intermediate-wavelength gravity anomalies can masquerade as the 'fifth force' if not properly corrected for.

  18. Agricultural geophysics: Past/present accomplishments and future advancements

    USDA-ARS?s Scientific Manuscript database

    Geophysical methods have become an increasingly valuable tool for application within a variety of agroecosystems. Agricultural geophysics measurements are obtained at a wide range of scales and often exhibit significant variability both temporally and spatially. The three geophysical methods predomi...

  19. A Unified Global Reference Frame of Vertical Crustal Movements by Satellite Laser Ranging

    PubMed Central

    Zhu, Xinhui; Wang, Ren; Sun, Fuping; Wang, Jinling

    2016-01-01

    Crustal movement is one of the main factors influencing the change of the Earth system, especially in its vertical direction, which affects people’s daily life through the frequent occurrence of earthquakes, geological disasters, and so on. In order to get a better study and application of the vertical crustal movement, as well as its changes, the foundation and prerequisite areto devise and establish its reference frame; especially, a unified global reference frame is required. Since SLR (satellite laser ranging) is one of the most accurate space techniques for monitoring geocentric motion and can directly measure the ground station’s geocentric coordinates and velocities relative to the centre of the Earth’s mass, we proposed to take the vertical velocity of the SLR technique in the ITRF2008 framework as the reference frame of vertical crustal motion, which we defined as the SLR vertical reference frame (SVRF). The systematic bias between other velocity fields and the SVRF was resolved by using the GPS (Global Positioning System) and VLBI (very long baseline interferometry) velocity observations, and the unity of other velocity fields and SVRF was realized, as well. The results show that it is feasible and suitable to take the SVRF as a reference frame, which has both geophysical meanings and geodetic observations, so we recommend taking the SLR vertical velocity under ITRF2008 as the global reference frame of vertical crustal movement. PMID:26867197

  20. Earth & Space Science PhDs, Class of 2001.

    ERIC Educational Resources Information Center

    Claudy, Nicholas; Henly, Megan; Migdalski, Chet

    This study documents the employment patterns and demographic characteristics of recent PhDs in earth and space science. It summarizes the latest annual survey of recent earth and space science PhDs conducted by the American Geological Institute, the American Geophysical Union, and the Statistical Research Center of the American Institute of…

  1. Detection of Antarctic oscillation signals in Earth's oblateness variations

    NASA Astrophysics Data System (ADS)

    Duan, Pengshuo; Liu, Genyou; Tu, Yi; Huang, Chengli

    2017-08-01

    Variations of Earth's oblateness (J 2) reflect a large scale mass redistribution within the Earth system. The climate effect causing J 2 interannual variations is still not clear, though previous studies indicated it may be related to EI Niño-Southern Oscillation (ENSO) and Pacific Decadal Oscillation (PDO). However, we have a new discovery of the significant Antarctic oscillation (AAO) signals in J 2 interannual variations, especially on 4-6 year scales based on cross wavelet and wavelet coherence analysis with 95% confidence test during 1979-2012. The results additionally indicate that the close phase relationship between J 2 and AAO (AAO leading J 2 variations by 3 ± 2 months in phase) is far superior to that between J 2 and ENSO/PDO on 4-6 year scales. In this work, we discuss, for the first time, a possible geophysical mechanism of AAO effecting J 2 variations. The investigations are based on the definition of AAO and its spatial-temporal behavior influencing the large-scale mass movement. Finally, an approximate quantitative estimate of the AAO imprint on J 2 with an emphasis on the atmospheric contribution is made.

  2. Stovetop Earth Pecan Pie

    NASA Astrophysics Data System (ADS)

    Robin, C. M.

    2005-12-01

    Many fluid mechanical experiments with direct applications to Earth Science are performed with sugary syrups using conceptually straightforward procedures. Corn syrup has indeed proven to be a godsend for those studying convection and related non-linear phenomena. In addition, however, it gives experimentalists a deep physical intuition for the interior workings of hot planets. The basic concepts behind plate tectonics and mantle convection are not difficult; indeed, although they may not be aware of it, most students probably have a basic intuitive understanding of fluid mechanics gained in their daily life. However, the large size and long time scale of geophysical processes may be quite intimidating to young students. Even a simple geophysical experiment requires a complicated array of coolers, heaters and measuring and recording equipment. It is of interest to introduce students to the geodynamical concepts that can be visualized in a high-tech lab using familiar processes and equipment. Using a homemade apparatus and grocery store supplies, I propose using a 'Stove-top Earth pecan pie' to introduce simple geodynamic concepts to middle- and high-school students. The initially cold syrup heats up and the pecans begin to float (continent formation), the syrup begins to convect (mantle convection), and convection slows down after the heat is removed (secular cooling). Even Wilson cycles can be simulated by moving the pan to one side or the other of the stovetop or heating element. The activity formally introduces students to convection and its application to the earth, and makes them think about plate motion, heat transfer, scaling, and experimental procedures. As an added bonus, they can eat their experiments after recess!

  3. Deep Interior: The first comprehensive geophysical investigation of an asteroid

    NASA Astrophysics Data System (ADS)

    Asphaug, E.; Belton, M.; Klaasen, K.; McFadden, L.; Ostro, S.; Safaeinili, A.; Scheeres, D.; Sunshine, J.; Yeomans, D.

    Near-Earth Objects (NEOs) come closer to Earth than any other celestial body, and their compositions are represented on Earth by thousands of well-studied meteorites. Yet we understand neither their origin, evolution, nor their geophysical behavior. These secrets are locked up in their unexplored interiors. Goal 1 of the NASA Strategic Plan emphasizes the requirement to catalogue and understand NEOs down to 1 km diameter. Goal 4 urges us to understand natural processes at work in the low gravity environment. Goal 5 expresses the need to explore the solar system and to learn how planets originated and evolved. In response to the NASA Strategic Plan we are proposing a NASA Discovery mission whose primary science objective is to greatly advance the realization of these Goals by conducting the first investigation of the global geophysics of an asteroid. Radio reflection data from 5 km orbit about a 1 km NEO will provide a tomographic 3D image of electromagnetic properties. Mechanical properties will be examined in the simplest possible way, using explosions to initiate seismic cratering events and to expose diverse interior units for spectroscopic analysis. Deep Interior is the lowest-risk, lowest cost path towards attaining the required characterization of NEOs. It breaks new ground for future missions to asteroids and comets and facilitates the design of reliable NEO technologies. Our science goals are as follows, and the techniques (radio science, imaging, IR spectroscopy, active surface science) will be described at this meeting: Asteroid Interiors. Radio, gravity, and seismology experiments give a complete first picture of an asteroid's deep interior, resolving inclusions, voids and unit boundaries at ˜ 30 m scales, and determining global and regional mechanical properties. Surface Geophysics. Blast experiments explore the structure and mechanics of the upper meters, demonstrate microgravity cratering, trigger natural geomorphic events, and expose subsurface

  4. Chloroplast movement.

    PubMed

    Wada, Masamitsu

    2013-09-01

    Chloroplast movement is important for plant survival under high light and for efficient photosynthesis under low light. This review introduces recent knowledge on chloroplast movement and shows how to analyze the responses and the moving mechanisms, potentially inspiring research in this field. Avoidance from the strong light is mediated by blue light receptor phototropin 2 (phot2) plausibly localized on the chloroplast envelop and accumulation at the week light-irradiated area is mediated by phot1 and phot2 localized on the plasma membrane. Chloroplasts move by chloroplast actin (cp-actin) filaments that must be polymerized by Chloroplast Unusual Positioning1 (CHUP1) at the front side of moving chloroplast. To understand the signal transduction pathways and the mechanism of chloroplast movement, that is, from light capture to motive force-generating mechanism, various methods should be employed based on the various aspects. Observation of chloroplast distribution pattern under different light condition by fixed cell sectioning is somewhat an old-fashioned technique but the most basic and important way. However, most importantly, precise chloroplast behavior during and just after the induction of chloroplast movement by partial cell irradiation using an irradiator with either low light or strong light microbeam should be recorded by time lapse photographs under infrared light and analyzed. Recently various factors involved in chloroplast movement, such as cp-actin filaments and CHUP1, could be traced in Arabidopsis transgenic lines with fluorescent protein tags under a confocal laser scanning microscope (CLSM) and/or a total internal reflection fluorescence microscope (TIRFM). These methods are listed and their advantages and disadvantages are evaluated. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  5. Critical zone architecture and processes: a geophysical perspective

    NASA Astrophysics Data System (ADS)

    Holbrook, W. S.

    2016-12-01

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

  6. Cross-disciplinary education: The use of interactive case studies to teach geophysical exploration

    NASA Astrophysics Data System (ADS)

    Boyd, Thomas M.; Romig, Phillip R.

    1997-06-01

    Cross-disciplinary training in the earth sciences is a difficult issue that has elicited concerns in academia and industry. Many problems associated with cross-disciplinary training stem from the fact that the earth sciences have evolved as a collection of loosely related, poorly coordinated specialties with little communication or interaction between them. As a result, when asked to teach across disciplinary boundaries, our instinctive reaction is to provide a watered-down version of the details that we teach our own students rather than the conceptual understanding that will help others work with us. This makes it difficult for earth scientists to provide the public with a coherent education in the fundamentals of earth science, and it has impeded the development of a common foundation for interaction between earth-science specialists. We have designed a computer-based learning environment for use in cross-disciplinary, earth-science education. This environment entails more than simply providing traditional course materials in an electronic form. Rather, the relevant material is conveyed through the use of a generalization of the case-study approach we refer to as the interactive case study approach. Through the use of computer simulations, students are allowed to interact with all aspects of the case, thereby helping them to become comfortable with the thought processes employed by a specialist and develop an intuitive understanding of the underlying physics. This educational model has been applied to the development of an introductory course in geophysical exploration geared toward upper-level undergraduate students not majoring in geophysics. The cases used in the course are couched in terms of a request for bid (RFB) requiring the use of a specific geophysical technique to solve a specific geologic or engineering problem. In responding to this RFB, students must write proposals, design geophysical surveys, interpret data derived from these surveys, and report

  7. PreAnalyseExtended: A graphical tool for (geophysical) time series analysis

    NASA Astrophysics Data System (ADS)

    Gebauer, André

    2016-04-01

    Time depending records of different geophysical and geodetic measurement systems require screening and post-processing, often combining the primary observable with additional measurement quantities from other external sensors or geophysical models. The ring laser 'G' located at the Geodetic Observatory Wettzell for example observes rotational ground motions depending on the sensor orientation. Hence tilt effects need to be corrected from the raw measurements of rotation. While the local tilt is taken from an independent time series of an auxiliary sensor, solid Earth tides and polar motion are corrected based on appropriate models. PreAnalyseExtended is a powerful software tool that combines the screening and processing of geophysical measurements of a variety of input sensors with a unique set of at least seven fully included models. This talk provides an introduction the important features of this open source tool.

  8. Faculty receives Excellence in Geophysical Education Award

    NASA Astrophysics Data System (ADS)

    Kruse, Sarah; Baldridge, W. Scott; Biehler, Shawn; Braile, Lawrence W.; Ferguson, John F.; Gilpin, Bernard E.; Jiracek, George R.

    “The second AGU Excellence in Geophysical Education Award was presented to the faculty of the Summer of Applied Geophysical Experience (SAGE): Scott Baldridge, Shawn Biehler, Larry Braile, John Ferguson, Bernard Gilpin, and George Jiracek. The persistence and commitment of this group has provided the geophysical community with a superb educational program for over 16 years, reaching nearly 400 students, including undergraduates, graduates, and professionals. The award was presented at the AGU Fall Meeting Honors Ceremony, which was held on December 8, 1998, in San Francisco, California.

  9. Centennial of a Pioneer in Meteorology, Geophysics

    NASA Astrophysics Data System (ADS)

    Schröder, Wilfried

    2004-06-01

    In 2004 we celebrate the 100th birthday of a great scientist and a leading proponent of our geophysical disciplines, Hans Ertel, who was formerly professor of geophysics and theoretical mechanics at Humboldt University in Berlin. He was also director of the (German) Institute of Metorology and Geophysics, and vice-president of the German Academy of Sciences; also in Berlin. Ertel was the founder of the Alexander von Humboldt Commission. Under his leadership, and in cooperation with other German academies, a comprehensive collection of letters from and to von Humboldt has been assembled and edited.

  10. Exploring Space, Exploring Earth: New Understanding of the Earth from Space Research

    NASA Astrophysics Data System (ADS)

    Lowman, Paul D., Jr.

    2002-08-01

    This book describes the impact of space flight on geology and geophysics, beginning with a foreword by Neil Armstrong, which illustrates how the exploration of space has lead us to a far deeper understanding of our own planet. Direct results from Earth-orbital missions include studies of Earth's gravity and magnetic fields. In contrast, the recognition of the economic and biological significance of impact craters on Earth is an indirect consequence of the study of the geology of other planets. The final chapter presents a new theory for the tectonic evolution of the Earth based on comparative planetology and the Gaia concept.

  11. Commerce geophysical lineament - Its source, geometry, and relation to the Reelfoot rift and New Madrid seismic zone

    USGS Publications Warehouse

    Langenheim, V.E.; Hildenbrand, T.G.

    1997-01-01

    The Commerce geophysical lineament is a northeast-trending magnetic and gravity feature that extends from central Arkansas to southern Illinois over a distance of ???400 km. It is parallel to the trend of the Reelfoot graben, but offset ???40 km to the northwest of the western margin of the rift floor. Modeling indicates that the source of the aeromagnetic and gravity anomalies is probably a mafic dike swarm. The age of the source of the Commerce geophysical lineament is not known, but the linearity and trend of the anomalies suggest a relationship with the Reelfoot rift, which has undergone episodic igneous activity. The Commerce geophysical lineament coincides with several topographic lineaments, movement on associated faults at least as young as Quaternary, and intrusions of various ages. Several earthquakes (Mb > 3) coincide with the Commerce geophysical lineament, but the diversity of associated focal mechanisms and the variety of surface structural features along the length of the Commerce geophysical lineament obscure its relation to the release of present-day strain. With the available seismicity data, it is difficult to attribute individual earthquakes to a specific structural lineament such as the Commerce geophysical lineament. However, the close correspondence between Quaternary faulting and present-day seismicity along the Commerce geophysical lineament is intriguing and warrants further study.

  12. Feds fund geophysical energy research

    NASA Astrophysics Data System (ADS)

    Bell, Peter M.

    Amid the current confusion surrounding the pending fate of the United States Department of Energy (President Reagan proposed a plan to ‘dismantle’ it), a rather large program, sometimes called ‘Physical Research in the Geosciences,’ survives in financially healthy condition. According to the recent report ‘Summary Outline of DOE Geoscience and Geoscience-Related Research (DOE/ER-0120, Feb. 1982), the amount of funding granted to university researchers for the current fiscal year is $16 million.In a procedure similar to other federal government unsolicited grant research proplate grams, funds are awarded to successful university applicants on the basis of research proposals. An interesting note is that apparently because of the uncertainties surrounding the futures of several federal programs, including the DOE, some researchers have assumed, incorrectly, that many sources of research funding may be discontinued. Meanwhile, program directors of the National Science Foundation have told Eos that their programs are experiencing a large increase in research proposals because investigators are apparently seeking other sources of funding. As the Office of Management Budget request for fiscal year 1983 stands at the present time, funding for geophysical energy research will be increased substantially under the Office of Basic Energy Sciences.

  13. Geophysical aspects of remote sensing

    NASA Technical Reports Server (NTRS)

    Watson, K.

    1971-01-01

    Results obtained through the NASA Earth Resources Aircraft Program at Mill Creek, Oklahoma, provide a case history example of the application of remote sensing to the identification of geologic rock units. Thermal infrared images are interpreted by means of a sequence of models of increasing complexity. The roles of various parameters are examined: rock properties (thermal inertia, albedo, emissivity), site location (latitude), season (sun's declination), atmospheric effects (cloud cover, transmission, air temperature), and topographic orientation (slope, azimuth). The results obtained at this site also illustrate the development of an important application of remote sensing in geologic identification. Relatively pure limestones and dolomites of the Mill Creek test area can be differentiated in nighttime infrared images, and facies changes between them can be detected along and across strike. The predominance on the earth's surface of sedimentary rocks, of which limestone and dolomite are major members, indicates the importance of this discrimination.

  14. Practices to enable the geophysical research spectrum: from fundamentals to applications

    NASA Astrophysics Data System (ADS)

    Kang, S.; Cockett, R.; Heagy, L. J.; Oldenburg, D.

    2016-12-01

    In a geophysical survey, a source injects energy into the earth and a response is measured. These physical systems are governed by partial differential equations and their numerical solutions are obtained by discretizing the earth. Geophysical simulations and inversions are tools for understanding physical responses and constructing models of the subsurface given a finite amount of data. SimPEG (http://simpeg.xyz) is our effort to synthesize geophysical forward and inverse methodologies into a consistent framework. The primary focus of our initial development has been on the electromagnetics (EM) package, with recent extensions to magnetotelluric, direct current (DC), and induced polarization. Across these methods, and applied geophysics in general, we require tools to explore and build an understanding of the physics (behaviour of fields, fluxes), and work with data to produce models through reproducible inversions. If we consider DC or EM experiments, with the aim of understanding responses from subsurface conductors, we require resources that provide multiple "entry points" into the geophysical problem. To understand the physical responses and measured data, we must simulate the physical system and visualize electric fields, currents, and charges. Performing an inversion requires that many moving pieces be brought together: simulation, physics, linear algebra, data processing, optimization, etc. Each component must be trusted, accessible to interrogation and manipulation, and readily combined in order to enable investigation into inversion methodologies. To support such research, we not only require "entry points" into the software, but also extensibility to new situations. In our development of SimPEG, we have sought to use leading practices in software development with the aim of supporting and promoting collaborations across a spectrum of geophysical research: from fundamentals to applications. Designing software to enable this spectrum puts unique

  15. Geophysical Fluid Dynamics Outreach Films

    NASA Astrophysics Data System (ADS)

    Aurnou, J. M.; Schwarz, J. W.; Noguez, G.

    2012-12-01

    Here we will present high definition films of laboratory experiments demonstrating basic fluid motions similar to those occurring in atmospheres and oceans. In these experiments, we use water to simulate the fluid dynamics of both the liquid (oceans) and gaseous (atmospheric) envelopes. To simulate the spinning of the earth, we carry out the experiments on a rotating table. For each experiment, we begin by looking at our system first without the effects of rotation. Then, we include rotation to see how the behavior of the fluid changes due to the Coriolis accelerations. Our hope is that by viewing these experiments one will develop a sense for how fluids behave both in rotating and non-rotating systems. By noting the differences between the experiments, it should then be possible to establish a basis to think about large-scale fluid motions that exist in Earth's oceans and atmospheres as well as on planets other than Earth.Plan view image of vortices in a rotating tank of fluid. Movies of such flows make accessible the often difficult to comprehend fluid dynamical processes that occur in planetary atmospheres and oceans.

  16. Tectonic investigation of Central Anatolia, Turkey, using geophysical data

    NASA Astrophysics Data System (ADS)

    Aydemir, Attila

    2009-07-01

    Central Anatolia in Turkey includes a number of internal basins and quite complex geology, but only three major faults can be observed on the surface. There are limited amount of investigations on the tectonic development, structure and history of this area. In this study, tectonic model of the Central Anatolia was investigated using geophysical data and it was compared with recently suggested tectonic models. Existence of two strike-slip faults that have orientations similar to the North Anatolian and East Anatolian Faults in the triple-junction area around the Bingol-Karliova region (eastern Turkey), led some geoscientists to consider the probability of another tectonic escape model in Central Anatolia. Strike-slip characteristics and slip directions of the Sereflikochisar-Aksaray and Ecemis Faults, and the geographical proximity of them are main reasons to consider this model. In this study, the tectonic escape model was investigated and criticized in detail using regional aeromagnetic, gravity, seismic and seismological data. Tectonic developments, faults and their relevance in tectonic setting of the Tuzgolu Basin, together with the comparison of the tectonic escape, and most recent wrench tectonic issues are comprehensively discussed. According to results of this study, existence of tectonic escape between the Sereflikochisar-Aksaray and Ecemis Faults, and geological reasons behind the model are found contradictory requiring geological and geophysical proofs. Moreover, strike direction of the Sereflikochisar-Aksaray Fault is also controversial. Instead of this, a recent model, the regional wrench tectonics appears more reasonable for Central Anatolia that was also supported by the GPS measurements, previous paleomagnetic studies and some recent papers. Geophysical investigation results pointed out that the counter-clockwise rotational movement of the Kirsehir Block to the east of Tuzgolu Basin has been driven by the Kirikkale-Erbaa and Sereflikochisar

  17. Earth Resources

    ERIC Educational Resources Information Center

    Brewer, Tom

    1970-01-01

    Reviews some of the more concerted, large-scale efforts in the earth resources areas" in order to help the computer community obtain insights into the activities it can jointly particpate in withthe earth resources community." (Author)

  18. Physicist + Geologist points to Geophysics Course

    ERIC Educational Resources Information Center

    Julian, Glenn M.; Stueber, Alan M.

    1974-01-01

    A two-quarter introductory course in geophysics at the advanced undergraduate/beginning graduate level is described. An outline of course content is provided, and mechanics of instruction are discussed. (DT)

  19. Tabletop Models for Electrical and Electromagnetic Geophysics.

    ERIC Educational Resources Information Center

    Young, Charles T.

    2002-01-01

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

  20. Physicist + Geologist points to Geophysics Course

    ERIC Educational Resources Information Center

    Julian, Glenn M.; Stueber, Alan M.

    1974-01-01

    A two-quarter introductory course in geophysics at the advanced undergraduate/beginning graduate level is described. An outline of course content is provided, and mechanics of instruction are discussed. (DT)

  1. Tabletop Models for Electrical and Electromagnetic Geophysics.

    ERIC Educational Resources Information Center

    Young, Charles T.

    2002-01-01

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

  2. JGR-Solid Earth and Planets GP editor appointed

    NASA Astrophysics Data System (ADS)

    Ken Hoffman (Physics Department, California Polytechnic State University, San Luis Obispo) has been appointed GP editor for papers submitted to the Journal of Geophysical Research—Solid Earth and Planets. His tenure will be from January 1987 to December 1988. Hoffman holds a Ph.D. in geophysics from the University of California, Berkeley, and has published extensively in the areas of rock magnetism, paleomagnetism, lunar paleointensity, and most recently, geomagnetic dipole field reversal modeling.

  3. The remote sensing needs of Arctic geophysics

    NASA Technical Reports Server (NTRS)

    Campbell, W. J.

    1970-01-01

    The application of remote sensors for obtaining geophysical information of the Arctic regions is discussed. Two significant requirements are to acquire sequential, synoptic imagery of the Arctic Ocean during all weather and seasons and to measure the strains in the sea ice canopy and the heterogeneous character of the air and water stresses acting on the canopy. The acquisition of geophysical data by side looking radar and microwave sensors in military aircraft is described.

  4. Geophysical applications for levee assessment

    NASA Astrophysics Data System (ADS)

    Chlaib, Hussein Khalefa

    Levees are important engineering structures that build along the rivers to protect the human lives and shield the communities as well as agriculture lands from the high water level events. Animal burrows, subsurface cavities, and low density (high permeability) zones are weakness features within the levee body that increase its risk of failure. To prevent such failure, continuous monitoring of the structure integrity and early detection of the weakness features must be conducted. Application of Ground Penetrating Radar (GPR) and Capacitively Coupled Resistivity (CCR) methods were found to be very effective in assessing the levees and detect zones of weakness within the levee body. GPR was implemented using multi-frequency antennas (200, 400, and 900 MHz) with survey cart/wheel and survey vehicle. The (CCR) method was applied by using a single transmitter and three receivers. Studying the capability and the effectiveness of these methods in levee monitoring, subsurface weakness feature detection, and studying the structure integrity of levees were the main tasks of this dissertation. A set of laboratory experiments was conducted at the Geophysics Laboratory of the University of Arkansas at Little Rock (UALR) to analyze the polarity change in GPR signals in the presence of subsurface voids and water-filled cavities. Also three full scale field expeditions at the Big Dam Bridge (BDB) Levee, Lollie Levee, and Helena Levee in Arkansas were conducted using the GPR technique. This technique was effective in detecting empty, water, and clay filled cavities as well as small scale animal burrows (small rodents). The geophysical work at BDB and Lollie Levees expressed intensive subsurface anomalies which might decrease their integrity while the Helena Levee shows less subsurface anomalies. The compaction of levee material is a key factor affecting piping phenomenon. The structural integrity of the levee partially depends on the density/compaction of the soil layers. A

  5. Solar-geophysical data number 499, March 1986, supplement

    NASA Technical Reports Server (NTRS)

    1986-01-01

    This supplement contains the description and explanation of the data in the monthly publication Solar-Geophysical Data, compiled by the National Geophysical Data Center (NGDC) in Boulder, Colo., USA. Solar-Geophysical Data is intended to keep research workers informed on a timely schedule of the major events of solar activity and the associated interplanetary, ionospheric, radio propagation and other geophysical effects.

  6. Geophysics of Small Planetary Bodies

    NASA Technical Reports Server (NTRS)

    Asphaug, Erik I.

    1998-01-01

    As a SETI Institute PI from 1996-1998, Erik Asphaug studied impact and tidal physics and other geophysical processes associated with small (low-gravity) planetary bodies. This work included: a numerical impact simulation linking basaltic achondrite meteorites to asteroid 4 Vesta (Asphaug 1997), which laid the groundwork for an ongoing study of Martian meteorite ejection; cratering and catastrophic evolution of small bodies (with implications for their internal structure; Asphaug et al. 1996); genesis of grooved and degraded terrains in response to impact; maturation of regolith (Asphaug et al. 1997a); and the variation of crater outcome with impact angle, speed, and target structure. Research of impacts into porous, layered and prefractured targets (Asphaug et al. 1997b, 1998a) showed how shape, rheology and structure dramatically affects sizes and velocities of ejecta, and the survivability and impact-modification of comets and asteroids (Asphaug et al. 1998a). As an affiliate of the Galileo SSI Team, the PI studied problems related to cratering, tectonics, and regolith evolution, including an estimate of the impactor flux around Jupiter and the effect of impact on local and regional tectonics (Asphaug et al. 1998b). Other research included tidal breakup modeling (Asphaug and Benz 1996; Schenk et al. 1996), which is leading to a general understanding of the role of tides in planetesimal evolution. As a Guest Computational Investigator for NASA's BPCC/ESS supercomputer testbed, helped graft SPH3D onto an existing tree code tuned for the massively parallel Cray T3E (Olson and Asphaug, in preparation), obtaining a factor xIO00 speedup in code execution time (on 512 cpus). Runs which once took months are now completed in hours.

  7. Geophysical observations at cavity collapse

    NASA Astrophysics Data System (ADS)

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

    2010-05-01

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

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

    NASA Astrophysics Data System (ADS)

    Eppelbaum, L. V.

    2012-04-01

    The Caucasian Mountains occupy an area of about 440,000 km2. A number of important mineral resources are concentrated there. Geophysical data on the geological structure of Caucasus can shed light on the basic principles of evolution of the Earth, the distribution of minerals and seismic activity. However, geophysical surveys under complex conditions are generally riddled by poor accessibility to certain mountainous regions, the unevenness of observation surfaces, as well as by a great variety and frequent changes of tectonic structures and geological bodies with variable physical properties. These factors either restrict geophysical surveys in difficult environments or confine the scope of useful information drawn from the results obtained. This has led to the development of special techniques in geophysical surveys, data processing and interpretation that draws heavily on the experience accumulated in the specific conditions of these mountainous regions. First applied geophysical observations in the Caucasus region - thermal measurements in boreholes - were carried out by Bazevich (1881) in the Absheron Peninsula. At the same time, start of the initial stage is usually referred to as the mid 20-s of the XX century, when the rare, but systematic geophysical observations (mainly gravity and magnetic) were begun in some Caucasian areas. Somewhat later began to apply the resistivity method. Mid 30-s is characterized by the beginning of application of borehole geophysics and seismic prospecting. The marine seismics firstly in the former Soviet Union was tested in the Caspian Sea. In general, the initial stage is characterized by slow, but steady rise (except during World War II) lasted until 1960. A basic stage (1960-1991) is characterized by very intensive employment of geophysical methods (apparently, any possible geophysical methods were tested in this region). At this time the Caucasus region is considered in the former Soviet Union as a geophysical polygon for

  9. Studies in geophysics groundwater contamination by Geophysics Study Committee

    SciTech Connect

    Not Available

    1984-01-01

    The book cites the massive application of chemicals to the land and the possibility of groundwater contamination and the extent of contamination on the natural scale. Movement by microscopic and macroscopic processes is discussed together with a description of chemical processes involved. This is followed by description of shallow land disposal of municipal waste and deep well injection. Several specific examples are then described and discussed. For example, the section on the Love Canal discusses a modeling system and recommendations for receiving the problem. Each section includes an abstract and a comprehensive set of references. It is well written, comprehensive and a valuable addition to the library of anyone working on the environmental problems of groundwater contamination.

  10. Contribution of Geophysical Prospecting to Geohazard Evaluation

    SciTech Connect

    Nicolich, Rinaldo

    2006-03-23

    The physical properties of the subsoil are studied using geophysical methods. These studies are always indirect, such as gravimetric, magnetometric, magnetotelluric or reflection-refraction seismic surveys and are often combined to obtain more accurate and reliable results. With these tools the oil industry commonly investigates the sedimentary basins to localize structures that may favor the accumulation of hydrocarbons. Above all, seismic prospecting allow the understanding of the underground geology, defining boundaries of the geological formations as well as mechanical and physical properties of the rocks. New cutting-edge techniques allow high quality data to be obtained in almost all geological contexts and make reflection seismic the most powerful tool in subsurface observations. The seismic method was utilized in geothermal resources investigation, research of water strategic resources, volcanic risks assessment, etc. The refraction method was the first to be used in the exploration of oil reservoirs. At present the industry employs mainly refraction seismics to study shallow formations. Conversely, university researchers have applied wide-angle reflection-refraction surveys to localize deep crustal interfaces analyzing the high amplitudes of the wide-angle reflections and the velocities obtained from the refracted signals. Moho discontinuity and velocity distribution within the crust were mapped out, indicating thickness and boundary conditions in different geological settings. The maps have been used in the analysis of geodynamical behavior and of active movements within the crust, useful for seismotectonic investigations. The further addition of the seismic reflection imaging, with deep penetration and long transects, completed multidisciplinary programs to unravel the structure of the crust with clear seismic images and models. High-resolution application of seismic has a central role in the identification and characterization of seismotectonic and

  11. The Seismoacoustic Wavefield: A New Paradigm in Studying Geophysical Phenomena

    NASA Astrophysics Data System (ADS)

    Arrowsmith, Stephen J.; Johnson, Jeffrey B.; Drob, Douglas P.; Hedlin, Michael A. H.

    2010-12-01

    The field of seismoacoustics is emerging as an important discipline in its own right, owing to the value of colocated seismic and infrasound arrays that sample elastic energy propagating in both the solid Earth and the atmosphere. The fusion of seismic and infrasonic data provides unique constraints for studying a broad range of topics including the source physics of natural and man-made events, interaction of mechanical waves in Earth's crust and atmosphere, source location and characterization, and inversion of atmospheric and shallow subsurface properties. This review article traces the seismoacoustic wavefield from source to receiver. Beginning at the source, we review the latest insights into the physics of natural and anthropogenic sources that have arisen from the analysis of seismoacoustic data. Next, a comparative review of 3-D models of the atmosphere and solid Earth and the latest algorithms for modeling the propagation of mechanical waves through these media provides the framework for a discussion of the seismoacoustic path. The optimal measurement of seismic and acoustic waves, including a discussion of instrumentation, as well as of array configurations and regional networks, is then outlined. Finally, we focus on broad research applications where the analysis of seismoacoustic data is starting to yield important new results, such as in the field of nuclear explosion monitoring. This review is intended to provide a primer on the field of seismoacoustics for seismologists or acousticians, while also providing a more general review of what constraints seismoacoustics can uniquely provide for understanding geophysical phenomena.

  12. Earth Day Plus 20, and Counting.

    ERIC Educational Resources Information Center

    Gilbert, Bil

    1990-01-01

    Presents a historical perspective of the environmental movement in the United States, beginning with Earth Day, 1970. Profiles "environmentalists" and describes environmental activities, achievements with environmental reform, turning points, and proenvironmental legislation from 1970-90. (MCO)

  13. Earth Day Plus 20, and Counting.

    ERIC Educational Resources Information Center

    Gilbert, Bil

    1990-01-01

    Presents a historical perspective of the environmental movement in the United States, beginning with Earth Day, 1970. Profiles "environmentalists" and describes environmental activities, achievements with environmental reform, turning points, and proenvironmental legislation from 1970-90. (MCO)

  14. Clay-Motion: Modeling Our Dynamic Earth.

    ERIC Educational Resources Information Center

    Borrello, Murray C.

    1994-01-01

    Provides easy to teach and understand laboratory exercises for three fundamental concepts (plate movement, rock mechanics, and geologic time) that are often left out of the geology and Earth science curriculum. (ZWH)

  15. Annual report of the Mizusawa Astrogeodynamics Observatory. Time Service and geophysical observations for the year 1991.

    NASA Astrophysics Data System (ADS)

    This annual report consists of two parts. The first part shows the results of the time services, i.e., time and latitude observations with the PZT, comparison of UTC(NAOM) with the Loran C and GPS (Global Positioning System), and comparison of the atomic clocks at the Mizusawa Astrogeodynamics Observatory. The second part shows the results of the geophysical observations at the Esashi Earth Tides Station and the absolute gravity measurements.

  16. Linking geodynamics and geophysical inversion with multiobservable probabilistic tomography

    NASA Astrophysics Data System (ADS)

    Afonso, Juan Carlos; Rawlinson, Nicholas; Yang, Yingjie; Zlotnik, Sergio; Ortega, Olga

    2017-04-01

    Our recent work (Afonso et al., 2013a,b; 2016) has demonstrated that multiobservable probabilistic tomography offers a sound method to characterize the thermochemical structure of the lithosphere and upper mantle and opens exiting new opportunities for deep-Earth imaging. In this method, all physical and chemical parameters defining an Earth model are linked together by fundamental thermodynamic relations, rather than by ad hoc empirical assumptions. This allows us to directly invert for the fundamental variables defining the physical state of the Earth's interior, namely, temperature, pressure, and major-element composition using a multitude of data sets with complementary strengths: body wave teleseismic data, surface wave phase dispersion data, gravity anomalies, long-wavelength gravity gradients, geoid height, receiver functions, absolute elevation, and surface heat flow data. In this probabilistic inversion scheme, traditional tomographic images of physical parameters such as 3-D seismic velocity become a "free" by-product. However, our tomographic images are, by design, also thermodynamically compatible with all the other inverted observables instead of satisfying one type of data set only. This is important, as any model deemed representative of the real physical state of the Earth's interior should pass the test of explaining other geophysical data sets as well. Inverting for "geodynamic" parameters such as viscosity or convection-related topography in 3D within this multiobservable probabilistic inverse framework is a major challenge, mainly due to the computational cost of solving the Stokes equations; we are not aware of previous attempts to do so with a probabilistic approach. However, recent advances on Reduced Order Modelling and Proper Generalized Decompositions have allowed us to overcome the traditional difficulties and create a probabilistic inversion framework that not only inverts for the physical state of the mantle but also for dynamic

  17. Content-Based Metadata Workbench: An innovative Tool to Compare Geophysical Parameters

    NASA Astrophysics Data System (ADS)

    Suresh, R.; Pfister, R.; Behnke, J.; Sachs, J.; D'Aria, D.

    2002-12-01

    Content Based Metadata Workbench (CBMW) is a prototype that seeks to improve the utility of information hidden in NASA's Earth science data systems by providing a global geophysical parameter data warehouse that is interoperable with metadata search systems. It will provide the following: a mechanism for content-based metadata searching of Earth science data, a research planning tool that includes inter-parameter visualization, and a broad warehouse of meaningful Earth science data to serve as a target for data mining. The team has just completed phase one of the prototype, which includes the development of CBMW data warehouse and integration of ordering interface and visualization of multiple parameters. CBMW takes an innovative approach to identify and compare anomalies and events from higher-level satellite remote sensing data products. CBMW has used level-3 Earth science data products and built a content-metadata "warehouse". This warehouse will serve as a data workbench for other data mining prototypes. CBMW used level 3 data products since they are based on widely accepted algorithms and relatively smaller in volume compared to lower level products. Using products from EOS Terra MODIS atmosphere data, TRMM fire and precipitation data, and AVHRR NDVI data, a database was developed to store geophysical parameters. The database was integrated with a GUI that enables detection of anomalies and relationships between multiple geophysical parameters through visualization. CBMW will provide the following: a mechanism for content-based Metadata searching of Earth science data, a research planning tool that includes inter-parameter visualization, and a broad warehouse of meaningful Earth science data to serve as a target for data mining. CBMW data warehouse is also interoperable with metadata search systems such as ECHO.

  18. Geophysical Investigation of Oldoinyo Lengai

    NASA Astrophysics Data System (ADS)

    Scheiber, S. E.; Webb, S. J.; Dirks, P. H.

    2006-12-01

    Oldoinyo Lengai, which means "Mountain of God" in Maasai, is a 2886 m high stratovolcano situated in Northern Tanzania, next to one of the large fault scarps that defines the western edge of the East African Rift Valley. Lengai is the only volcano in the world that erupts natrocarbonatite lava and has been in a state of near-eruption since 1983. A large amount of work has been done in terms of the geology and petrology of this unique volcano, but very little has been done in terms of geophysics. A research team from the University of the Witwatersrand, South Africa will be conducting a gravity and differential GPS survey on Lengai during December 2006 and January 2007. Seismic monitoring of the volcano will also take place for the duration of the survey using vertical 1 Hz geophones. A gravity profile collected over the volcano by the British Schools Exploring Society in 2004 shows a negative anomaly of approximately 185 mGals. This is after a terrain correction is applied to the data using 1:50000 digitized maps and a vertical prism formula. A single seismometer, with a frequency of 1Hz and then 0.033 Hz, was set up on the volcano in 2001 and 2002 by a graduate student from the University of Washington. A few local volcanotectonic (VT) events were recorded; however the research team was unable to conclude whether the events were from Lengai or the nearby rift. A sustained non-harmonic tremor signal with a fairly broad spectral peak was also observed, but no very long-period (VLP) signals. The gravity and DGPS data collected during the 2006/2007 survey will be processed and used as a baseline for future measurements on the volcano. The data will also be modeled in an attempt to determine the size and position of the magma chamber. These gravity data will be compared with the profile collected in 2004 in an attempt to see whether there have been any large subsurface mass changes over the past two years, or the extent of weathering. Recorded seismicity will be used

  19. The sixth presentation of the Maurice Ewing Medal by the American Geophysical Union and the United States Navy to Manik Talwani for leadership in marine geophysics

    NASA Astrophysics Data System (ADS)

    Uyeda, Seiya; Talwani, Manik

    Manik Talwani's impact on the geosciences clearly places him among those who deserve to be honored as a Ewing medalist. He has contributed major advances to our understanding of Earth's fundamental characteristics and has provided direction that will help guide geological/geophysical research long into the future.Born in Patiala, India, in 1933, Manik earned bachelor's and master's degrees at Delhi University. In the mid-1950s he moved to the United States and enrolled in Columbia University for his Ph.D. studies. It was the beginning of a long association between Manik and Columbia. When he earned his Ph.D. in 1959, it was already apparent that he was destined to make a significant impact on the geosciences. He has been the recipient of several important awards for his contributions and leadership. These include the first Krishnan Medal in 1965, from his home country, and the Macelwane Award from the American Geophysical Union, in 1967, for his pioneering achievements in the application of marine gravimetry to studies of Earth's crust and upper mantle. Since 1970, Manik has been a professor of geology at Columbia, and for 8 years he served as director of Lamont-Doherty Geological Observatory. This evening, for his continued contributions and leadership, Manik is being awarded the Maurice Ewing Medal. He is truly qualified for this distinction, based on his many important original contributions to marine geophysics, ocean technology and instrumentation, and also for his outstanding service to marine science.

  20. Optimizing the design of geophysical experiments: Is it worthwhile?

    NASA Astrophysics Data System (ADS)

    Curtis, Andrew; Maurer, Hansruedi

    Determining the structure, composition, and state of the Earth's subsurface from measured data is the principal task of many geophysical experiments and surveys. Standard procedures involve the recording of appropriate data sets followed by the application of data analysis techniques to extract the desired information. While the importance of new tools for the analysis stage of an experiment is well recognized, much less attention seems to be paid to improving the data acquisition.A measure of the effort allocated to data analysis research relative to that devoted to data acquisition research is presented in Figure 1. Since 1955 there have been more than 10,000 publications on inversion methods alone, but in the same period only 100 papers on experimental design have appeared in journals. Considering that the acquisition component of an experiment defines what information will be contained in the data, and that no amount of data analysis can compensate for the lack of such information, we suggest that greater effort be made to improve survey planning techniques. Furthermore, given that logistical and financial constraints are often stringent and that relationships between geophysical data and model parameters describing the Earths subsurface are generally complicated, optimizing the design of an experiment may be quite challenging. Here we review experimental design procedures that optimize the benefit of a field survey, such that maximum information about the target structures is obtained at minimum cost. We also announce a new Web site and e-mail group set up as a forum for communication on survey design research and application.

  1. ORBSIM- ESTIMATING GEOPHYSICAL MODEL PARAMETERS FROM PLANETARY GRAVITY DATA

    NASA Technical Reports Server (NTRS)

    Sjogren, W. L.

    1994-01-01

    The ORBSIM program was developed for the accurate extraction of geophysical model parameters from Doppler radio tracking data acquired from orbiting planetary spacecraft. The model of the proposed planetary structure is used in a numerical integration of the spacecraft along simulated trajectories around the primary body. Using line of sight (LOS) Doppler residuals, ORBSIM applies fast and efficient modelling and optimization procedures which avoid the traditional complex dynamic reduction of data. ORBSIM produces quantitative geophysical results such as size, depth, and mass. ORBSIM has been used extensively to investigate topographic features on the Moon, Mars, and Venus. The program has proven particulary suitable for modelling gravitational anomalies and mascons. The basic observable for spacecraft-based gravity data is the Doppler frequency shift of a transponded radio signal. The time derivative of this signal carries information regarding the gravity field acting on the spacecraft in the LOS direction (the LOS direction being the path between the spacecraft and the receiving station, either Earth or another satellite). There are many dynamic factors taken into account: earth rotation, solar radiation, acceleration from planetary bodies, tracking station time and location adjustments, etc. The actual trajectories of the spacecraft are simulated using least squares fitted to conic motion. The theoretical Doppler readings from the simulated orbits are compared to actual Doppler observations and another least squares adjustment is made. ORBSIM has three modes of operation: trajectory simulation, optimization, and gravity modelling. In all cases, an initial gravity model of curved and/or flat disks, harmonics, and/or a force table are required input. ORBSIM is written in FORTRAN 77 for batch execution and has been implemented on a DEC VAX 11/780 computer operating under VMS. This program was released in 1985.

  2. Discover Earth

    NASA Technical Reports Server (NTRS)

    Steele, Colleen

    1998-01-01

    Discover Earth is a NASA-sponsored project for teachers of grades 5-12, designed to: (1) enhance understanding of the Earth as an integrated system; (2) enhance the interdisciplinary approach to science instruction; and (3) provide classroom materials that focus on those goals. Discover Earth is conducted by the Institute for Global Environmental Strategies in collaboration with Dr. Eric Barron, Director, Earth System Science Center, The Pennsylvania State University; and Dr. Robert Hudson, Chair, the Department of Meteorology, University of Maryland at College Park. The enclosed materials: (1) represent only part of the Discover Earth materials; (2) were developed by classroom teachers who are participating in the Discover Earth project; (3) utilize an investigative approach and on-line data; and (4) can be effectively adjusted to classrooms with greater/without technology access. The Discover Earth classroom materials focus on the Earth system and key issues of global climate change including topics such as the greenhouse effect, clouds and Earth's radiation balance, surface hydrology and land cover, and volcanoes and climate change. All the materials developed to date are available on line at (http://www.strategies.org) You are encouraged to submit comments and recommendations about these materials to the Discover Earth project manager, contact information is listed below. You are welcome to duplicate all these materials.

  3. The Environmental Geophysics Web Site and Geophysical Decision Support System (GDSS)

    EPA Science Inventory

    This product provides assistance to project managers, remedial project managers, stakeholders, and anyone interested in on-site investigations or environmental geophysics. The APM is the beta version of the new U.S. EPA Environmental Geophysics Web Site which includes the Geophys...

  4. The Environmental Geophysics Web Site and Geophysical Decision Support System (GDSS)

    EPA Science Inventory

    This product provides assistance to project managers, remedial project managers, stakeholders, and anyone interested in on-site investigations or environmental geophysics. The APM is the beta version of the new U.S. EPA Environmental Geophysics Web Site which includes the Geophys...

  5. Using Grand Challenges For Innovative Teaching in Structural Geology, Geophysics, and Tectonics

    NASA Astrophysics Data System (ADS)

    McDaris, J. R.; Tewksbury, B. J.; Wysession, M. E.

    2012-12-01

    An innovative approach to teaching involves using the "Big Ideas" or "Grand Challenges" of a field, as determined by the research community in that area, as the basis for classroom activities. There have been several recent efforts in the areas of structural geology, tectonics, and geophysics to determine these Grand Challenges, including the areas of seismology ("Seismological Grand Challenges in Understanding Earth's Dynamic Systems"), mineral physics ("Unlocking the Building Blocks of the Planet"), EarthScope-related science ("Unlocking the Secrets of the North American Continent: An EarthScope Science Plan for 2010-2020"), and structural geology and tectonics (at the Structural Geology and Tectonics Forum held at Williams College in June, 2012). These research community efforts produced frameworks of the essential information for their fields with the aim of guiding future research. An integral part of this, however, is training the next generation of scientists, and using these Big Ideas as the basis for course structures and activities is a powerful way to make this happen. When activities, labs, and homeworks are drawn from relevant and cutting-edge research topics, students can find the material more fascinating and engaging, and can develop a better sense of the dynamic process of scientific discovery. Many creative ideas for incorporating the Grand Challenges of structural geology, tectonics, and geophysics in the classroom were developed at a Cutting Edge workshop on "Teaching Structural Geology, Geophysics, and Tectonics in the 21st Century" held at the University of Tennessee in July, 2012.

  6. Russian Meteorological and Geophysical Rockets of New Generation

    NASA Astrophysics Data System (ADS)

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

    2015-09-01

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

  7. Global gravity field models and their use for geophysical modelling

    NASA Astrophysics Data System (ADS)

    Pail, R.

    2015-12-01

    During the last decade, the successful operation of the dedicated satellite missions GOCE and GRACE have revolutionized our picture of the Earth's gravity field. They delivered static global gravity field maps with high and homogeneous accuracy for spatial length-scales down to 70-80 km. The current satellite-only models of the fifth generation including GOCE data have reached accuracies of about 2 cm in geoid height and less than 0.7 mGal in gravity anomalies at 100 km spatial half-wavelength. However, the spatial resolution of gravity models derived from satellite data is limited. Since precise knowledge of the Earth's gravity field structure with very high resolution is essential in solid Earth applications such as lithospheric modelling, geological interpretation and exploration geophysics, satellite-only models are complemented by combined gravity field models, which contain very high-resolution gravity field information obtained by terrestrial gravity measurements over continents, and satellite altimetry over the oceans. To further increase the spatial resolution beyond 10-20 km, measured terrestrial and satellite data can also be augmented by high-resolution gravity field signals synthesized from topographic models. In this contribution an overview of the construction of satellite-only and combined global gravity field models is given. The specific characteristics of the individual input data and the resulting models will be assessed, and their impact for geophysical modelling will be discussed. On the basis of selected case studies, commission and omission errors and thus the contribution and impact of satellite gravity data on gravity field applications will be quantified, and the benefit of current satellite gravity data shall be investigated and demonstrated. Future gravity field missions beyond GRACE Follow-On will provide global gravity field information with further increased accuracy, spatial and temporal resolution. In an international initiative

  8. Earth Science Information System (ESIS)

    USGS Publications Warehouse

    ,

    1982-01-01

    The Earth Science Information System (ESIS) was developed in 1981 by the U.S. Geological Survey's Office of the Data Administrator. ESIS serves as a comprehensive data management facility designed to support the coordination, integration, and standardization of scientific, technical, and bibliographic data of the U.S. Geological Survey (USGS). ESIS provides, through an online interactive computer system, referral to information about USGS data bases, data elements which are fields in the records of data bases, and systems. The data bases contain information about many subjects from several scientific disciplines such as: geology, geophysics, geochemistry, hydrology, cartography, oceanography, geography, minerals exploration and conservation, and satellite data sensing.

  9. AGU supports Earth science radio show

    NASA Astrophysics Data System (ADS)

    Cole, Stephen

    Radio listeners across the country will soon get a daily introduction to the Earth and space sciences when a new syndicated radio program, “Earth and Sky,” debuts this fall. Produced by Deborah Byrd and Joel Block of Austin, Texas, the creative team behind the long-running “Star Date” radio program, “Earth and Sky” premieres on September 30. The program is being produced in association with the American Geophysical Union.“‘Earth and Sky’ is a new vehicle for the dissemination of accurate and up-to-date information on Earth and space sciences,” says AGU Executive Director Fred Spilhaus. “It has tremendous potential to advance one of AGU's fundamental missions: to make the results of scientific research available to the public.”

  10. Sainte Victoire Mountain - International Earth Science Olympiads

    NASA Astrophysics Data System (ADS)

    Berenguer, Jean-Luc

    2013-04-01

    The IESO is an annual competition for secondary school students. The students have to test their skills in all major areas of Earth sciences, including geology, geophysics, meteorology, oceanography, terrestrial astronomy and environmental sciences. The theoretical examination includes problems which are supposed to measure the participants' knowledge and understanding of Earth science areas. The practical examination consists of tasks which are designed to assess participants' abilities to carry out scientific investigations in earth science inquiries. he IESO is the only International Olympiad that includes an International Team Field Investigation. Each national team has also to present a special geological site from his country. This poster will show the fieldwork made with and by the French students/teachers team for the last IESO which took place in Argentina. The main aim of the IESO is to encourage students' interest and public awareness of Earth Science and to enhance Earth science learning.

  11. Study of movement of the western and central belts of Peninsular Malaysia using GPS data analysis

    NASA Astrophysics Data System (ADS)

    Ramli, Siti Hafizah; Samsudin, Abdul Rahim

    2014-09-01

    Since the large earthquakes in Sumatera and Nias, there were some tremors incidents at Bukit Tinggi. Therefore, a study on the earth's crust movement and the effects of the earthquake in Indonesia on the tectonic blocks of Peninsular Malaysia have been carried out using GPS data analysis. GPS data from five MyRTKnet stations within Peninsular Malaysia have been analyzed to monitor the movement of two major tectonic blocks of Peninsular Malaysia which are the western belt represented by the Behrang (BEHR) and UPM Serdang (UPMS) stations and the central belt represented by Bentong (BENT), Jerantut (JRNT) and Temerloh (TLOH) stations. GPS data recorded from 2005 to 2010 were analysed based on horizontal and vertical displacements of the respective stations by using Trimble Business Centre (TBC) software. Based on the results of accumulated displacements of recorded GPS data from January 2006 to December 2013, it shows that the western belt which represented by UPMS has shifted 0.096m towards northwest with changes of ellipsoidal height of +0.030m while the central belt which represented by TLOH has shifted 0.080m towards northwest with changes of ellipsoidal height of -0.015m. Meanwhile, BENT station which is located on the Bentong-Raub suture zone turns to its original position as well as JRNT station. However, BEHR station which are located in western belt do not show any movements. All of these movements may be due to the influence of reactive faults in the stations area stimulated by several large earthquakes that occurred in 2005 to 2010. Study on using the GPS data analysis and combine with integrated geophysical methods are necessary to understand in detail about the tectonic evolution of Peninsular Malaysia.

  12. The patient movement as an emancipation movement

    PubMed Central

    Williamson, Charlotte

    2008-01-01

    Abstract Objective  To suggest that the patient movement is an emancipation movement. Background  The patient movement is young and fragmented; and it can seem confusing because it lacks an explicit ideology with intellectual and theoretical underpinnings. Methods  Drawing mainly on the experiences and the published writings of patient activists, the author identified eight aspects of the patient movement that could be compared with aspects of recognized emancipation movements: the radicalization of activists; the creation of new knowledge; the identification of guiding principles; the sense of direction; the unmasking of new issues; schisms within the movement and allies outside it; and the gradual social acceptance of some of the ideas (here standards of health care) that activists work to promote. Results  Similarities between certain aspects of the patient movement and of the recognized emancipation movements were close. Conclusion  The patient movement can be regarded as an emancipation movement, albeit an immature one. PMID:18494955

  13. Geophysical Measurements at Merseburg Cathedral

    NASA Astrophysics Data System (ADS)

    Meier, Thomas; Erkul, Ercan; Schulte-Kortnack, Detlef; Sobott, Robert; Hilbert, Helene; Esel, Yunus; Tesch, Marcel; Wiemann, Timo

    2017-04-01

    Merseburg Cathedral has been founded in 1015 by Bishop Thietmar von Merseburg and has been converted into a gothic cathedral from 1510 to 1517 by Bishop Thilo von Trotha. The cathedral together with the cloister, the castle and several appurtenant buildings are well preserved. The entire complex represents one of the most complete examples of medieval royal palaces and bishop's sees in Germany northeast of the Roman Limes. Here we present examples of geophysical measurements at the cathedral namely ultrasonic surface measurements, ground penetrating radar (GPR) as well as thermographic measurements. Ultrasonic surface measurements have been carried out at epitaphs made of sandstone to quantify changes in stone properties due to weathering. The 95 measurements reveal a strong variability in Rayleigh wave velocities ranging from about 800 m/s to 2000 m/s. Unweathered parts of the sandstone epitaphs show Rayleigh wave velocities of about 1500 m/s. A reduction in Rayleigh wave velocities hints at loosening of the rock surface whereas an increase is due to surficial black crusts with pores filled mainly by gypsum. Waveform inversion of the dispersed Rayleigh waveform yields depth profiles of the shear-wave velocity indicating the thickness of altered surficial layers. Also a loosening below the black crust may be detected non-destructively. A number of measurements have been repeated after one year and after a rainy day. Statistical analysis shows that random errors in Rayleigh wave velocities are less than about 3 %. Increase of moisture in porous sandstones leads to stronger damping of the Rayleigh wave and consequently to a reduction in Rayleigh wave velocities by up to about 10 %. At strongly altered epitaphs a reduction in Rayleigh wave velocity by up to 20 % has been observed within one year. Within one day an increase of up to about 7 % may indicate stiffening of black crusts due to moisture absorption. GPR measurements have been performed at several locations

  14. Understanding the lithosphere in complex tectonic scenarios by integrating geophysical data: The Pyrenees case study

    NASA Astrophysics Data System (ADS)

    Campanyà, Joan; Fullea, Javier; Ledo, Juanjo; Queralt, Pilar; Marcuello, Alex; Liesa, Montserrat; Muñoz, Josep Anton

    2016-04-01

    Tectonic processes dominate the development of the outermost layer of the Earth over a timescale of millions of years. The locations where these processes take place provide a great opportunity for Earth scientists to study and understand the dynamics and properties of the lithosphere. The Pyrenees are a particular case of continental collision formed as a result of the collision between the Iberian and European plates, which caused the subduction of the Iberian lower crust below the European crust. Large amounts of geophysical data have been acquired in the area providing spectacular images of lithospheric subduction beneath the Western and Central Pyrenees, confirming the occurrence of this generally well-understood process. The Eastern Pyrenees, however, are a most puzzling part of the orogen and the geodynamical evolution of this area cannot be understood without the influence of the Neogene Mediterranean rifting, following the continental collision. The complexity of this area and the controversy of the geophysical results set in debate concepts well recognized in the other parts of the Pyrenees such as the subduction of the Iberian lower crust and the depth of the lithosphere-asthenosphere boundary. The aims of this study are to characterise major tectonic and geophysical variations along the Pyrenean mountain range at a lithospheric-scale and constrain the causes of the observed lateral variations. A preliminary model of the lithospheric configuration and dynamics, based on magnetotelluric geophysical results, has been developed and constrained using independent and available geophysical, geological and geochemical data. Computational petrology methods, using Litmod, were used for integrated modelling of all data.

  15. Brief overview of geophysical probing technology

    SciTech Connect

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

    1982-02-01

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

  16. Negligible Risk for Epidemics after Geophysical Disasters

    PubMed Central

    Floret, Nathalie; Viel, Jean-François; Mauny, Frédéric; Hoen, Bruno

    2006-01-01

    After geophysical disasters (i.e., earthquakes, volcanic eruptions, tsunamis), media reports almost always stress the risk for epidemics; whether this risk is genuine has been debated. We analyzed the medical literature and data from humanitarian agencies and the World Health Organization from 1985 to 2004. Of >600 geophysical disasters recorded, we found only 3 reported outbreaks related to these disasters: 1 of measles after the eruption of Pinatubo in Philippines, 1 of coccidioidomycosis after an earthquake in California, and 1 of Plasmodium vivax malaria in Costa Rica related to an earthquake and heavy rainfall. Even though the humanitarian response may play a role in preventing epidemics, our results lend support to the epidemiologic evidence that short-term risk for epidemics after a geophysical disaster is very low. PMID:16704799

  17. Dynamical approach to study and interpret geodynamical and geophysical effects

    NASA Astrophysics Data System (ADS)

    Ferronsky, V.

    2009-04-01

    It was proved by satellite and terrestrial observation that the hydrostatics, which operates by the outer forces, is not able to ensure correct description and interpretation of geodynamical and geophysical effects. In order to find solution of the problem, we applied to dynamics. For this purpose the outer force field of the Earth was replaced by its inner (volumetric) force pressure. Doing so we introduced new physical basis for study dynamics of the planet in its own force field. The analytics for that is as follows. The body is considered as a system of n elementary particles (n → ∞) of masses mi and many degrees of freedom. The volumetric moment of a particle pi is written as pi = midri/dt. Then the moment of momentum M of the system is found to be derivative from the moment of inertia I in the form: M = ∑piri = ∑miridri/dt = d/dt(∑½ miri2) = ½ dI/dt. Then derivative on time from M gives the energy of the system as second derivative from I: M' = ∑pidri/dt + ∑ridpi/dt = ½I" where ∑pidri/dt = 2T is the kinetic energy and ∑ridpi/dt = U is the potential energy of the oscillating moment of inertia (interacting particles). So, equation of dynamical equilibrium (equation of state) of a body, where the interacted particles are presented by nonlinear oscillators, is ½I" = 2T + U. We used this for study and interpretation of oscillation and rotation parameters of the Earth. Note that the center of mass of the Earth is presented here by a surface of asymmetric spheroid. For more information see our works: Ferronsky V.I. and S.V.Ferronsky (2007). Dynamics of the Earth, Scientific World, Moscow; Ferronsky V.I. (2008) Non-averaged virial theorem for natural systems: http://zhurnal.ape.relarn.ru/articles/2008/066e.pdf

  18. First Paleomagnetic Map of the Easternmost Mediterranean Derived from Combined Geophysical-Geological Analysis

    NASA Astrophysics Data System (ADS)

    Eppelbaum, Lev; Katz, Youri

    2014-05-01

    paleotectonic criteria for oil and gas discovery in this region. Extensive geological-geophysical investigations have been carried out in this region, and a significant number of deep boreholes have been drilled. However integrated estimation of the deep structure of the hydrocarbon host deposits and their space-time evolution in terms of the modern geodynamics (first of all, plate tectonics: Ben-Avraham and Ginzburg, 1990; Robertson, 1998; Ben-Avraham et al., 2002, 2006; Jimenez-Munt et al., 2003; Le Pichon and Kreemer, 2010), are comparatively recent (Eppelbaum and Katz, 2011, 2012a; Eppelbaum et al., 2012, 2014). We elucidate this geodynamic relationship by examining the structural floors within the following tectonic-geophysical zones: (1) regions of development of continental crust of the Nubian, Arabian and Sinai plates, (2) remaining oceanic crust of the eastern Mediterranean, and (3) the thinned continental crust of the terrane belt. A series of new gravity and magnetic maps developed by employing satellite and airborne data (as well their transformations) accompanied by tectonic schemes were constructed (Eppelbaum and Katz, 2011; Eppelbaum et al., 2012a, 2012b, 2014). These new maps are crucial to a better understanding of the dynamics of hydrocarbon basin formation within the continental and shelf depressions, as well as the deep depressions of the easternmost Mediterranean where gas deposits in zones of oceanic crust evolution have only recently (April 2013) begun to be exploited. Careful attention should be paid to the blocks of oceanic (basaltic) crust with reverse magnetization that were discovered (Ben-Avraham et al., 2002; Eppelbaum, 2006). This issue was very briefly (Eppelbaum and Katz, 2012a) explained as paleomagnetic Kiama zone of inverse polarity and demands separate consideration. An integrated magnetic-gravity-seismic analysis conducted along three interpretation profiles unambiguously indicates the presence of blocks of the Earth's crust with reverse

  19. Integrated Approaches On Archaeo-Geophysical Data

    NASA Astrophysics Data System (ADS)

    Kucukdemirci, M.; Piro, S.; Zamuner, D.; Ozer, E.

    2015-12-01

    Key words: Ground Penetrating Radar (GPR), Magnetometry, Geophysical Data Integration, Principal Component Analyse (PCA), Aizanoi Archaeological Site An application of geophysical integration methods which often appealed are divided into two classes as qualitative and quantitative approaches. This work focused on the application of quantitative integration approaches, which involve the mathematical and statistical integration techniques, on the archaeo-geophysical data obtained in Aizanoi Archaeological Site,Turkey. Two geophysical methods were applied as Ground Penetrating Radar (GPR) and Magnetometry for archaeological prospection on the selected archaeological site. After basic data processing of each geophysical method, the mathematical approaches of Sums and Products and the statistical approach of Principal Component Analysis (PCA) have been applied for the integration. These integration approches were first tested on synthetic digital images before application to field data. Then the same approaches were applied to 2D magnetic maps and 2D GPR time slices which were obtained on the same unit grids in the archaeological site. Initially, the geophysical data were examined individually by referencing with archeological maps and informations obtained from archaeologists and some important structures as possible walls, roads and relics were determined. The results of all integration approaches provided very important and different details about the anomalies related to archaeological features. By using all those applications, integrated images can provide complementary informations as well about the archaeological relics under the ground. Acknowledgements The authors would like to thanks to Scientific and Technological Research Council of Turkey (TUBITAK), Fellowship for Visiting Scientists Programme for their support, Istanbul University Scientific Research Project Fund, (Project.No:12302) and archaeologist team of Aizanoi Archaeological site for their support

  20. What can earth tide measurements tell us about ocean tides or earth structure?

    NASA Technical Reports Server (NTRS)

    Baker, T. F.

    1978-01-01

    Current experimental problems in Earth tides are reviewed using comparisons of tidal gravity and tilt measurements in Europe with loading calculations are examples. The limitations of present day instrumentation and installation techniques are shown as well as some of the ways in which they can be improved. Many of the geophysical and oceanographic investigations that are possible with Earth tide measurements are discussed with emphasis on the percentage accuracies required in the measurements in order to obtain new information about Earth or its oceans.

  1. Earth observing satellite: Understanding the Earth as a system

    NASA Technical Reports Server (NTRS)

    Soffen, Gerald

    1990-01-01

    There is now a plan for global studies which include two very large efforts. One is the International Geosphere/Biosphere Program (IGBP) sponsored by the International Council of Scientific Unions. The other initiative is Mission to Planet Earth, an unbrella program for doing three kinds of space missions. The major one is the Earth Observation Satellite (EOS). EOS is large polar orbiting satellites with heavy payloads. Two will be placed in orbit by NASA, one by the Japanese and one or two by ESA. The overall mission measurement objectives of EOS are summarized: (1) the global distribution of energy input to and energy output from the Earth; (2) the structure, state variables, composition, and dynamics of the atmosphere from the ground to the mesopause; (3) the physical and biological structure, state, composition, and dynamics of the land surface, including terrestrial and inland water ecosystems; (4) the rates, important sources and sinks, and key components and processes of the Earth's biogeochemical cycles; (5) the circulation, surface temperature, wind stress, sea state, and the biological activity of the oceans; (6) the extent, type, state, elevation, roughness, and dynamics of glaciers, ice sheets, snow and sea ice, and the liquid equivalent of snow in the global cryosphere; (7) the global rates, amounts, and distribution of precipitation; and (8) the dynamic motions of the Earth (geophysics) as a whole, including both rotational dynamics and the kinematic motions of the tectonic plates.

  2. Tamara Shapiro Ledley Receives 2013 Excellence in Geophysical Education Award: Citation

    NASA Astrophysics Data System (ADS)

    Reiff, Patricia

    2014-01-01

    It gives me great pleasure to cite Tamara Shapiro Ledley for the AGU Excellence in Geophysical Education Award "for her outstanding sustained leadership in Earth systems and climate change education." Tamara has shown an ongoing commitment to bridging the scientific and educational communities to make geophysical science knowledge and data accessible and usable to teachers and students and by extension to all citizens. She works extensively with both the scientific and educational communities. She began her educational work in 1990 as the leader for weather and climate in my Teacher Research program at Rice University. She continued as the lead for atmospheric sciences in our projects Earth Today and Museums Teaching Planet Earth, which introduced her to the Earth Science Information Partners (ESIP Federation). She has served many roles at ESIP, including creating the Standing Committee for Education and serving as vice president. ESIP recognized her many accomplishments with its President's Award in 2012. At TERC her education and outreach efforts have blossomed. She was the lead author of the "Earth as a System" investigation of the GLOBE Teacher's Guide. She was a member of the original Digital Library for Earth System Education (DLESE) Data Access Working Group in 2001, where the idea for a cookbook-like resource to facilitate the use of Earth science data by teachers and students resulted in her leading the development of the "Earth Exploration Toolbook" (EET), which allows teachers to easily access and use real scientific data in the classroom. Her efforts were recognized with the EET being awarded Science Magazine's Science Prize for Online Research in Education in 2011.

  3. Peace Education, ESD and the Earth Charter: Interconnections and Synergies

    ERIC Educational Resources Information Center

    Toh, Swee-Hin; Cawagas, Virginia Floresca

    2010-01-01

    This article provides a review of how the values and principles of the Earth Charter initiative relate to two specific innovative movements of educational transformation, namely peace education and education for sustainable development (ESD). The interconnections and synergies between these movements and the Earth Charter are highlighted.…

  4. Peace Education, ESD and the Earth Charter: Interconnections and Synergies

    ERIC Educational Resources Information Center

    Toh, Swee-Hin; Cawagas, Virginia Floresca

    2010-01-01

    This article provides a review of how the values and principles of the Earth Charter initiative relate to two specific innovative movements of educational transformation, namely peace education and education for sustainable development (ESD). The interconnections and synergies between these movements and the Earth Charter are highlighted.…

  5. Spatial scale analysis in geophysics - Integrating surface and borehole geophysics in groundwater studies

    USGS Publications Warehouse

    Paillet, Frederick L.; Singhroy V.H.Hansen D.T.Pierce R, R

    2002-01-01

    Integration of geophysical data obtained at various scales can bridge the gap between localized data from boreholes and site-wide data from regional survey profiles. Specific approaches to such analysis include: 1) comparing geophysical measurements in boreholes with the same measurement made from the surface; 2) regressing geophysical data obtained in boreholes with water-sample data from screened intervals; 3) using multiple, physically independent measurements in boreholes to develop multivariate response models for surface geophysical surveys; 4) defining subsurface cell geometry for most effective survey inversion methods; and 5) making geophysical measurements in boreholes to serve as independent verification of geophysical interpretations. Integrated analysis of surface electromagnetic surveys and borehole geophysical logs at a study site in south Florida indicates that salinity of water in the surficial aquifers is controlled by a simple wedge of seawater intrusion along the coast and by a complex pattern of upward brine seepage from deeper aquifers throughout the study area. This interpretation was verified by drilling three additional test boreholes in carefully selected locations.

  6. Earth Observation

    NASA Image and Video Library

    2016-06-19

    ISS048e002082 (06/19/2016) --- Crew members aboard the International Space Station take numerous images of the Earth, both day and night to record the images that provide NASA scientists with data to gain a deeper understanding of our Planet. Sometimes Science joins with Art when the images are so meaningful that the crew pauses to reflect on our Earths beauty.

  7. Rainbow Earth.

    ERIC Educational Resources Information Center

    Arizona State Dept. of Library and Archives, Phoenix.

    The environment is a great concern in the 1990s, and everyone needs to work at maintaining our planet. The 1992 Arizona State Library Reading Program, "Rainbow Earth," provides children with many techniques they can use to help the Earth. This reading program guide provides information on the following: goals, objectives, and evaluation;…

  8. Earth Observation

    NASA Image and Video Library

    2014-07-14

    Earth Observation taken during a night pass by the Expedition 40 crew aboard the International Space Station (ISS). Folder lists this as: HDR night series (New Zealand pass). The Space Station Remote Manipulator System (SSRMS) arm is visible. Aurora visible over Earth limb.

  9. Earth Observation

    NASA Image and Video Library

    2014-11-25

    ISS042E015787 (11/25/2014) --- NASA astronaut Terry Virts captured this beautiful sunset on board the International Space Station. Astronauts, and cosmonauts are treated to many changing views of the Earth and stars as the station carries them around the Earth.

  10. Earth tides

    SciTech Connect

    Harrison, J.C.

    1984-01-01

    Nineteen papers on gravity, tilt, and strain tides are compiled into this volume. Detailed chapters cover the calculation of the tidal forces and of the Earth's response to them, as well as actual observations of earth tides. Partial Contents: On Earth tides. The tidal forces: Tidal Forces. New Computations of the Tide-Generating Potential. Corrected Tables of Tidal Harmonics. The Theory of Tidal Deformations. Body Tides on an Elliptical, Rotating, Elastic and Oceanless Earth, Deformation of the Earth by Surface Loads. Gravimetric Tidal Loading Computed from Integrated Green's Functions. Tidal Friction in the Solid Earth. Loading Tides Versus Body Tides. Lunar Tidal Acceleration from Earth Satellite Orbit Analysis. Observations: gravity. Tidal Gravity in Britain: Tidal Loading and the Spatial Distribution of the Marine Tide. Tidal Loading along a Profile Europe-East Africa-South Asia-Australia and the Pacific Ocean. Detailed Gravity-Tide Spectrum between One and Four Cycles per Day. Observations: tilt and strain. Cavity and Topographic Effects in Tilt and Strain Measurement. Observations of Local Elastic Effects on Earth Tide Tilts and Strains.

  11. GETMAG - A New Geophysical Tool

    NASA Astrophysics Data System (ADS)

    Schmidt, P.; Clark, D.; Bick, M.; Binks, R.; Du, J.; Foley, C.; Gnanarajan, S.; Leslie, K.; Sullivan, P.; Thorn, B.; Tilbrook, D.

    2004-05-01

    CSIRO is developing a new instrument for mineral exploration. The instrument, GETMAG, measures the magnetic gradient tensor and the components of the magnetic field. The sensors are high temperature superconducting quantum interference devices (SQUIDs), or HTSs. The acronym is largely historical and stands for Glass Earth Tensor Magnetic Airborne Gradiometer. The GETMAG instument measures magnetic gradients via a novel application of high temperature superconducting tape flip-chipped onto a SQUID sensor. A gradiometer structure incorporating two opposing pick-up loops is patterned onto a tape. Due to the spatial separation of these loops, a magnetic gradient will produce a Meissner shielding current in the tape. The current is magnetically coupled to the SQUID sensor thus providing a direct measurement of the magnetic gradient. The tape is rotated to detect all gradients orthogonal to the axis of rotation. Three rotating tape systems are required to measure the full tensor. The gradients in combination with the TMI yield better resolution for magnetic surveys. Direction to individual sources and their magnetic moments (reduced according to distance) can be determined directly from the tensor. Results from test surveys, where the GETMAG system was rotated manually, show that the gradient can be measured to an accuracy of a few nT/m. It is estimated that improving the mechanical structure, spinning the system at about 600 rpm and using an improved data extraction algorithm can reduce this noise figure by two orders of magnitude. The vector components at this stage are very inaccurate since most of the development undertaken to date has been aimed at measuring the gradients. The systems operate better as gradiometers than as magnetometers and will not challenge total field instruments such as proton precession or alkali-vapour magnetometers as scalar instruments. The GETMAG concept has wide ranging applications in mineral exploration, environmental studies, ordnance

  12. Archaeological Geophysics in Israel: Past, Present and Future

    NASA Astrophysics Data System (ADS)

    Eppelbaum, L. V.

    2009-04-01

    localization of archaeological targets: An introduction. Geoinformatics, 11, No.1, 19-28. Eppelbaum, L.V., 2005. Multilevel observations of magnetic field at archaeological sites as additional interpreting tool. Proceed. of the 6th Conference of Archaeological Prospection, Roma, Italy, 4 pp. Eppelbaum, L.V., 2007a. Localization of Ring Structures in Earth's Environments. Proceed. of the 7th Conference of Archaeological Prospection. Nitra, Slovakia, 145-148. Eppelbaum, L.V., 2007b. Revealing of subterranean karst using modern analysis of potential and quasi-potential fields. Proceed. of the Symp. on the Application of Geophysics to Engineering and Environmental Problems, Denver, USA, 797-810. Eppelbaum, L.V., 2008a. Remote operated vehicle geophysical survey using magnetic and VLF methods: proposed schemes for data processing and interpretation. Proceed. of the Symp. on the Application of Geophysics to Engineering and Environmental Problems, Philadelphia, USA, 938-963. Eppelbaum, L.V., 2008b. On the application of near-surface temperature investigations for delineation of archaeological targets. Trans. of the 1st International Workshop on Advances in Remote Sensing for Archaeology and Cultural Heritage Management, Rome, Italy, 179-183. Eppelbaum, L.V., 2009. Application of microgravity at archaeological sites in Israel: some estimation derived from 3D modeling and quantitative analysis of gravity field. Proceed. of the Symp. on the Application of Geophysics to Engineering and Environmental Problems, Denver, USA, 10 pp. Eppelbaum, L. and Ben-Avraham, Z., 2002. On the development of 4D geophysical Data Base of archaeological sites in Israel. Trans. of the Conf. of the Israel Geol. Soc. Ann. Meet., MaHagan - Lake Kinneret, Israel, p.21. Eppelbaum, L., Ben-Avraham, Z., and Itkis, S., 2003a. Ancient Roman Remains in Israel provide a challenge for physical-archaeological modeling techniques. First Break, 21 (2), 51-61. Eppelbaum, L.V., Ben-Avraham, Z., and Itkis, S.E., 2003b

  13. Surveying the earth's resources from space

    USGS Publications Warehouse

    Pecora, William T.

    1967-01-01

    Two developments, aerial photography and airborne geophysical surveying techniques, have already increased the rate at which new knowledge of the world's resources can be acquired. But even with far wider use of the tools and techniques already available, the problems that face us are greater than our current ability to solve them. Fortunately, some of the further acceleration required can be obtained through use of remote-sensing devices mounted in high-flying aircraft and earth-orbiting satellites.

  14. Measuring Orientation Of The Earth With GPS

    NASA Technical Reports Server (NTRS)

    Freedman, Adam P.

    1992-01-01

    Report discusses feasibility of using Global Positioning System (GPS) to resolve short-term fluctuations (days or hours) in locations of points on crust of Earth to within centimeters or millimeters. With full constellation of satellites and ground receiving stations, system provides rapid (within 12 hours) determinations of variations in orientation. Measurements used to enhance precision of spacecraft navigation and in geophysical and meteorological studies of daily exchanges of angular momentum among fluid core, crust and mantle, oceans, and atmosphere.

  15. Evaluation of borehole geophysical logs at the Sharon Steel Farrell Works Superfund site, Mercer County, Pennsylvania

    USGS Publications Warehouse

    McAuley, Steven D.

    2004-01-01

    On April 14?15, 2003, geophysical logging was conducted in five open-borehole wells in and adjacent to the Sharon Steel Farrell Works Superfund Site, Mercer County, Pa. Geophysical-logging tools used included caliper, natural gamma, single-point resistance, fluid temperature, and heatpulse flowmeter. The logs were used to determine casing depth, locate subsurface fractures, identify water-bearing fractures, and identify and measure direction and rate of vertical flow within the borehole. The results of the geophysical logging were used to determine the placement of borehole screens, which allows monitoring of water levels and sampling of water-bearing zones so that the U.S. Environmental Protection Agency can conduct an investigation of contaminant movement in the fractured bedrock. Water-bearing zones were identified in three of five boreholes at depths ranging from 46 to 119 feet below land surface. Borehole MR-3310 (MW03D) showed upward vertical flow from 71 to 74 feet below land surface to a receiving zone at 63-68 feet below land surface, permitting potential movement of ground water, and possibly contaminants, from deep to shallow zones. No vertical flow was measured in the other four boreholes.

  16. Invariant-tori-like Lagrangian coherent structures in geophysical flows.

    PubMed

    Beron-Vera, Francisco J; Olascoaga, María J; Brown, Michael G; Koçak, Huseyin; Rypina, Irina I

    2010-03-01

    The term "Lagrangian coherent structure" (LCS) is normally used to describe numerically detected structures whose properties are similar to those of stable and unstable manifolds of hyperbolic trajectories. The latter structures are invariant curves, i.e., material curves of fluid that serve as transport barriers. In this paper we use the term LCS to describe a different type of structure whose properties are similar to those of invariant tori in certain classes of two-dimensional incompressible flows. Like stable and unstable manifolds, invariant tori are invariant curves that serve as transport barriers. There are many differences, however, between traditional LCSs and invariant-tori-like LCSs. These differences are discussed with an emphasis on numerical techniques that can be used to identify invariant-tori-like LCSs. Structures of this type are often present in geophysical flows where zonal jets are present. A prime example of an invariant-torus-like LCS is the transport barrier near the core of the polar night jet in the Earth's lower and middle stratospheres in the austral winter and early spring; this is the barrier that traps ozone-depleted air inside the ozone hole. This example is investigated using both a simple analytically prescribed flow and a velocity field produced by a general circulation model of the Earth's atmosphere.

  17. Geophysical Hazards and Preventive Disaster Management of Extreme Natural Events

    NASA Astrophysics Data System (ADS)

    Ismail-Zadeh, A.; Takeuchi, K.

    2007-12-01

    Geophysical hazard is potentially damaging natural event and/or phenomenon, which may cause the loss of life or injury, property damage, social and economic disruption, or environmental degradation. Extreme natural hazards are a key manifestation of the complex hierarchical nonlinear Earth system. An understanding, accurate modeling and forecasting of the extreme hazards are most important scientific challenges. Several recent extreme natural events (e.g., 2004 Great Indian Ocean Earthquake and Tsunami and the 2005 violent Katrina hurricane) demonstrated strong coupling between solid Earth and ocean, and ocean and atmosphere. These events resulted in great humanitarian tragedies because of a weak preventive disaster management. The less often natural events occur (and the extreme events are rare by definition), the more often the disaster managers postpone the preparedness to the events. The tendency to reduce the funding for preventive disaster management of natural catastrophes is seldom follows the rules of responsible stewardship for future generations neither in developing countries nor in highly developed economies where it must be considered next to malfeasance. Protecting human life and property against earthquake disasters requires an uninterrupted chain of tasks: from (i) understanding of physics of the events, analysis and monitoring, through (ii) interpretation, modeling, hazard assessment, and prediction, to (iii) public awareness, preparedness, and preventive disaster management.

  18. Quantitative Analysis of Piezoelectric and Seismoelectric Anomalies in Subsurface Geophysics

    NASA Astrophysics Data System (ADS)

    Eppelbaum, Lev

    2017-04-01

    , A., 2000, Seismic-electric effect method on guided and reflected waves. Physics and Chemistry of the Earth, Part A: Solid Earth and Geodesy, 25, No.4, 333-336. Butler, K.E., Russell, R.D., Kepic A.W. and Maxwell, M., 1994. Mapping of a stratigraphic boundary by its seismoelectric response. SAGEEP '94 Conference Proceedings, 689-699. Eppelbaum, L.V., 2010. Archaeological geophysics in Israel: Past, Present and Future. Advances in Geosciences, 24, 45-68. Dupuis, J.C., Butler, K.E., Kepic, A.W. and Harris, B.D., 2009. Anatomy of a seismoelectric conversion: Measurements and conceptual modeling in boreholes penetrating a sandy aquifer. Journal of Geophysical Research, 114, B10306, doi:10.1029/2008JB005939 Eppelbaum, L.V., 2011. Study of magnetic anomalies over archaeological targets in urban conditions. Physics and Chemistry of the Earth, 36, No. 16, 1318-1330. Eppelbaum, L.V., 2014. Geophysical observations at archaeological sites: Estimating informational content. Archaeological Prospection, 21, No. 2, 25-38. Eppelbaum, L.V., 2015. Quantitative interpretation of magnetic anomalies from thick bed, horizontal plate and intermediate models under complex physical-geological environments in archaeological prospection. Archaeological Prospection, 23, No. 2, 255-268. Eppelbaum, L.V., Alperovich, L., Zheludev, V. and Pechersky, A., 2011. Application of informational and wavelet approaches for integrated processing of geophysical data in complex environments. Proceed. of the 2011 SAGEEP Conference, Charleston, South Carolina, USA, 24, 24-60. Eppelbaum, L.V., Itkis, S.E. and Khesin, B.E., 2000. Optimization of magnetic investigations in the archaeological sites in Israel, In: Special Issue of Prospezioni Archeologiche "Filtering, Modeling and Interpretation of Geophysical Fields at Archaeological Objects", 65-92. Eppelbaum, L.V., Khesin, B.E. and Itkis, S.E., 2001. Prompt magnetic investigations of archaeological remains in areas of infrastructure development: Israeli

  19. Ancient Earth, Alien Earths Event

    NASA Image and Video Library

    2014-08-20

    Panelists pose for a group photo at the “Ancient Earth, Alien Earths” Event at NASA Headquarters in Washington, DC Wednesday, August 20, 2014. The event was sponsored by NASA, the National Science Foundation (NSF), and the Smithsonian Institution and highlighted how research on early Earth could help guide our search for habitable planets orbiting other stars. Photo Credit: (NASA/Aubrey Gemignani)

  20. Using Geophysical Data in the Texas High School Course, Geology, Meteorology, and Oceanography

    NASA Astrophysics Data System (ADS)

    Ellins, K.; Olson, H.; Pulliam, J.; Schott, M. J.

    2002-12-01

    Science educators working directly with scientists to develop inquiry-based instructional materials in Earth science yield some of the best results. The TEXTEAMS (Texas Teachers Empowered for Achievement in Mathematics and Science) Leadership Training for the Texas high school science course, Geology, Meteorology and Oceanography (GMO) is one example of a successful program that provides high-quality training to master teachers using geophysical data collected by scientists at The University of Texas Institute for Geophysics (UTIG). TEXTEAMS is a certification program of professional development and leadership training sponsored by the National Science Foundation that is part of the Texas Statewide Systemic Initiative. UTIG scientists teamed with science educators at the Charles A. Dana Center for Mathematics and Science Education at UT and the Texas Education Agency to develop inquiry-based instructional materials for eight GMO modules. Our learning activities help students and teachers understand how Earth scientists interpret the natural world and test their hypotheses, and provide opportunities for the use of technology in classroom science learning; they are aligned with national and state teaching standards. Examples of TEXTEAMS GMO learning activities that use geophysical data. 1. Neotectonics: radiocarbon dates and elevation above current sea level of raised coral reefs in the New Georgia Islands are used to calculate rates of tectonic uplift and as a basis for the development of a conceptual model to explain the pattern of uplift that emerges from the data. 2. Large Igneous Provinces:geophysical logging data collected on ODP Leg 183 (Kerguelen Plateau) are analyzed to identify the transition from sediment to basement rock. 3. The Search for Black Gold: petroleum exploration requires the integration of geology, geophysics, petrophysics and geochemistry. Knowledge gained in previous GMO modules is combined with fundamental knowledge about economics to

  1. Digital geologic and geophysical data of Bangladesh

    USGS Publications Warehouse

    Persits, Feliks M.; Wandrey, C.J.; Milici, R.C.; Manwar, Abdullah

    1997-01-01

    The data set for these maps includes arcs, polygons, and labels that outline and describe the general geologic age and geophysical fields of Bangladesh. Political boundaries are provided to show the general location of administrative regions and state boundaries. Major base topographic data like cities, rivers, etc. were derived from the same paper map source as the geology.

  2. Geophysical subsurface imaging for ecological applications.

    PubMed

    Jayawickreme, Dushmantha H; Jobbágy, Esteban G; Jackson, Robert B

    2014-03-01

    Ecologists, ecohydrologists, and biogeochemists need detailed insights into belowground properties and processes, including changes in water, salts, and other elements that can influence ecosystem productivity and functioning. Relying on traditional sampling and observation techniques for such insights can be costly, time consuming, and infeasible, especially if the spatial scales involved are large. Geophysical imaging provides an alternative or complement to traditional methods to gather subsurface variables across time and space. In this paper, we review aspects of geophysical imaging, particularly electrical and electromagnetic imaging, that may benefit ecologists seeking clearer understanding of the shallow subsurface. Using electrical resistivity imaging, for example, we have been able to successfully show the effect of land-use conversions to agriculture on salt mobilization and leaching across kilometer-long transects and to depths of tens of meters. Recent advances in ground-penetrating radar and other geophysical imaging methods currently provide opportunities for subsurface imaging with sufficient detail to locate small (≥5 cm diameter) animal burrows and plant roots, observe soil-water and vegetation spatial correlations in small watersheds, estuaries, and marshes, and quantify changes in groundwater storage at local to regional scales using geophysical data from ground- and space-based platforms. Ecologists should benefit from adopting these minimally invasive, scalable imaging technologies to explore the subsurface and advance our collective research.

  3. Sedimentological analysis using geophysical well logs

    SciTech Connect

    Izotova, T.S. )

    1993-09-01

    The application of geophysical well logs in sedimentology and stratigraphic prospecting holds great promise in solving a number of geological problems. A suite of logs provides data on a wide range of rock properties: vertical and lateral variation of resistivity, natural polarization, natural and induced radioactivity, shear strength, and acoustic properties. Each of these properties is controlled by the depositional environment of the sediments and their later diagenesis. The attention of geologists and geophysicists is drawn to new techniques in the interpretation of geophysical well logs for exploration, appraisal, and development of oil and gas fields. The relationship between geophysical logs and depositional environments is explored. Bulk composition, rock structure, and texture and facies variation can be quantified by electric log parameters. Also, the possibility of using logs to demonstrate long- and short-period sedimentary cycles is demonstrated. Methods of sedimentological analysis using geophysical well logs are demonstrated. The importance of a genetic approach in the interpretation of geological sequences and paleogeological reconstructions is emphasized using examples taken from oil and gas prospecting operations in the Ukraine.

  4. Rare earths

    SciTech Connect

    Vijayan, S.; Melnyk, A.J.; Singh, R.D.; Nuttall, K.

    1989-01-01

    For conventional applications, there is limited demand for rare earth elements as well as yttrium and scandium. But the emergence of new high technology applications such as supermagnets, lasers, and superconductors should result in significant demand for some of these elements. This article examines the anticipated applications and demands for rare earth elements over the next decade. It also looks at the implications on the use of available resources. In the context of a growing demand, process methods are reviewed for the recovery of rare earth elements from conventional and unconventional resources. And the article also discusses the challenges facing the mining industry in meeting this opportunity.

  5. Basic research and data analysis for the earth and ocean physics applications program and for the National Geodetic Satellite Program

    NASA Technical Reports Server (NTRS)

    1976-01-01

    Data analysis and supporting research in connection with the following objectives are discussed: (1) provide a precise and accurate geometric description of the earth's surface, (2) provide a precise and accurate mathematical description of the earth's gravitational field, and (3) determine time variations of the geometry of the ocean surface, the solid earth, the gravity field and other geophysical parameters.

  6. Geophysics applications in critical zone science: emerging topics

    USDA-ARS?s Scientific Manuscript database

    Geophysical studies have resulted in remarkable advances in characterization of critical zone. The geophysics applications uncover the relationships between structure and function in subsurface as they seek to define subsurface structural units with individual properties of retention and trans...

  7. Modeling of the Earth's gravity field using the New Global Earth Model (NEWGEM)

    NASA Technical Reports Server (NTRS)

    Kim, Yeong E.; Braswell, W. Danny

    1989-01-01

    Traditionally, the global gravity field was described by representations based on the spherical harmonics (SH) expansion of the geopotential. The SH expansion coefficients were determined by fitting the Earth's gravity data as measured by many different methods including the use of artificial satellites. As gravity data have accumulated with increasingly better accuracies, more of the higher order SH expansion coefficients were determined. The SH representation is useful for describing the gravity field exterior to the Earth but is theoretically invalid on the Earth's surface and in the Earth's interior. A new global Earth model (NEWGEM) (KIM, 1987 and 1988a) was recently proposed to provide a unified description of the Earth's gravity field inside, on, and outside the Earth's surface using the Earth's mass density profile as deduced from seismic studies, elevation and bathymetric information, and local and global gravity data. Using NEWGEM, it is possible to determine the constraints on the mass distribution of the Earth imposed by gravity, topography, and seismic data. NEWGEM is useful in investigating a variety of geophysical phenomena. It is currently being utilized to develop a geophysical interpretation of Kaula's rule. The zeroth order NEWGEM is being used to numerically integrate spherical harmonic expansion coefficients and simultaneously determine the contribution of each layer in the model to a given coefficient. The numerically determined SH expansion coefficients are also being used to test the validity of SH expansions at the surface of the Earth by comparing the resulting SH expansion gravity model with exact calculations of the gravity at the Earth's surface.

  8. Geophysical monitoring in a hydrocarbon reservoir

    NASA Astrophysics Data System (ADS)

    Caffagni, Enrico; Bokelmann, Goetz

    2016-04-01

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

  9. Geophysical Signitures From Hydrocarbon Contaminated Aquifers

    NASA Astrophysics Data System (ADS)

    Abbas, M.; Jardani, A.

    2015-12-01

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

  10. Geophysical Technologies to Image Old Mine Works

    SciTech Connect

    Kanaan Hanna; Jim Pfeiffer

    2007-01-15

    ZapataEngineering, Blackhawk Division performed geophysical void detection demonstrations for the US Department of Labor Mine Safety and Health Administration (MSHA). The objective was to advance current state-of-practices of geophysical technologies for detecting underground mine voids. The presence of old mine works above, adjacent, or below an active mine presents major health and safety hazards to miners who have inadvertently cut into locations with such features. In addition, the presence of abandoned mines or voids beneath roadways and highway structures may greatly impact the performance of the transportation infrastructure in terms of cost and public safety. Roads constructed over abandoned mines are subject to potential differential settlement, subsidence, sinkholes, and/or catastrophic collapse. Thus, there is a need to utilize geophysical imaging technologies to accurately locate old mine works. Several surface and borehole geophysical imaging methods and mapping techniques were employed at a known abandoned coal mine in eastern Illinois to investigate which method best map the location and extent of old works. These methods included: 1) high-resolution seismic (HRS) using compressional P-wave (HRPW) and S-wave (HRSW) reflection collected with 3-D techniques; 2) crosshole seismic tomography (XHT); 3) guided waves; 4) reverse vertical seismic profiling (RVSP); and 5) borehole sonar mapping. In addition, several exploration borings were drilled to confirm the presence of the imaged mine voids. The results indicated that the RVSP is the most viable method to accurately detect the subsurface voids with horizontal accuracy of two to five feet. This method was then applied at several other locations in Colorado with various topographic, geologic, and cultural settings for the same purpose. This paper presents the significant results obtained from the geophysical investigations in Illinois.

  11. Geophysical Constraints on Sediment Dispersal Systems

    NASA Astrophysics Data System (ADS)

    Johnstone, Elizabeth Anne Carruthers

    Geophysical and geological approaches were employed to understand sediment dispersal systems and their response to various forcing functions (i.e., sea level fluctuations, tectonic deformation, sediment supply, and climate change). Two end member marine environments were studied; one with high precipitation and sediment discharge (Gulf of Papua, Papua New Guinea) and the other with low precipitation and sediment discharge (Oceanside Littoral Cell). The high-sedimentation rate in the Gulf of Papua (GoP) yields high-fidelity records of Earth history. As part of the NSF Margins Source-to-Sink (S2S) program, we acquired CHIRP and core data across the GoP continental shelf that complemented onshore and offshore research in the region. CHIRP seismic data imaged three Holocene sedimentary lobes. The older Central lobe is downlapped by two younger lobes to the north and south. Sediment analysis showed that the older Central lobe has an elemental signature similar to the younger Northern lobe with both sourced from the Purari River watershed and lobe migration appears to be climatically controlled. The Southern lobe has elemental signatures more consistent with the Fly River watershed. Our results suggest the northern rivers began depositing sediments on the shelf during the Holocene sea level rise in the central region of the GoP and migrated abruptly north at ~2 kybp. Conversely, during the early Holocene transgression, sediments in the Fly drainage system were sequestered onshore infilling accommodation created in the large low-relief coastal plain during the sea level rise. Upon infilling the onshore accommodation, the Fly River delivered sediment to the ocean and formed the Southern lobe. Such differences in onshore storage capacity may introduce a lag between low-gradient rivers (Type I) with a large coastal plain versus high-gradient river systems (Type II) with small coastal plains. The second study site is in the sediment-starved Oceanside Littoral Cell (OCL) of

  12. Satellite-tracking and Earth dynamics research programs

    NASA Technical Reports Server (NTRS)

    1981-01-01

    The major focus for operations during this period was the preliminary MERIT Campaign and its intensive tracking of LAGEOS for polar motion and Earth rotation studies. The data acquired from LAGEOS were used for other geophysical investigations, including studies of crustal dynamics, and Earth and ocean tides, and for the general development of precision orbit determination. The network performed regular tracking of several other retroreflector satellites including GEOS-1, GEOS-3, BE-C, and Starlette for refined determinations of station coordinates and Earth's gravity field and for studies of solid Earth dynamics.

  13. A case for catastrophic early degassing of the earth.

    NASA Technical Reports Server (NTRS)

    Fanale, F. P.

    1971-01-01

    Evidence is given for the occurrence in early earth history of massive escape of volatiles from the interior of the earth to its surface, which must have had catastrophic proportions. The mechanism and time of this event are inferred from the abundances and distribution of volatiles in the atmosphere, hydrosphere and crust, and from meteorite studies, and geophysical and astronomical observations. This event is linked to the melting of the earth during accretion which resulted in the concentration of U, Th, K and Pb in the outermost portion of the earth and in virtually complete expulsion of nonradiogenic Ar, Ne and Kr from its interior.

  14. Aristoteles - An ESA mission to study the earth's gravity field

    NASA Astrophysics Data System (ADS)

    Lambeck, K.

    In preparing for its first Solid-Earth Program, ESA has studied a satellite concept for a mission dedicated to the precise determination of the earth's geopotential (gravitational and magnetic) fields. Data from such a mission are expected to make substantial contributions to a number of research and applications fields in solid-earth geophysics, oceanography and global-change monitoring. The impact of a high-resolution gravity-field mission on studies of the various earth-science problems is assessed. The current state of our knowledge in this area is discussed and the ability of low-orbit satellite gradiometry to contribute to their solution is demonstrated.

  15. Laser ranging contributions to monitoring and interpreting Earth orientation changes

    NASA Technical Reports Server (NTRS)

    Gross, R. S.

    2002-01-01

    The groundwork for a new field in the geophysical sciences - space geodesy - was laid in the 1960s with the development of satellite and lunar laser ranging systems, along with the development of very long baseline interferometry systems, for the purpose of studying crustal plate motion and deformation, the Earth's gravitational field, and Earth orientation changes. The availability of accurate, routine determinations of the Earth orientation parameters (EOPs) afforded by the launch of the LAser GEOdynamics Satellite (LAGEOS) on May 4, 1976, and the subsequent numerous studies of the LAGEOS observations, has led to a greater understanding of the causes of the observed changes in the Earth's orientation.

  16. Laser ranging contributions to monitoring and interpreting Earth orientation changes

    NASA Technical Reports Server (NTRS)

    Gross, R. S.

    2002-01-01

    The groundwork for a new field in the geophysical sciences - space geodesy - was laid in the 1960s with the development of satellite and lunar laser ranging systems, along with the development of very long baseline interferometry systems, for the purpose of studying crustal plate motion and deformation, the Earth's gravitational field, and Earth orientation changes. The availability of accurate, routine determinations of the Earth orientation parameters (EOPs) afforded by the launch of the LAser GEOdynamics Satellite (LAGEOS) on May 4, 1976, and the subsequent numerous studies of the LAGEOS observations, has led to a greater understanding of the causes of the observed changes in the Earth's orientation.

  17. A German Geophysics School Project First steps to bring geophysical topics to schoolclasses

    NASA Astrophysics Data System (ADS)

    Schneider, S.

    2002-12-01

    In Germany Geophysics is a science with almost none or a bad reputation. People do not know to distinguish between Geophysics, Geography and Geology. In order to change the public view on Geosciences, a,School Project Geophysics' is going to be created at the Institute of Meteorology and Geophysics, Johann Wolfgang Goethe University, Frankfurt, which will offer geophysical ideas, methodes and scientific results to schoolclasses. After researches like PISA or TIMSS (third international Math and Nature-Science test) new concepts in education will be required. Interdisciplinary tasks are demanded by national and international commissions.\\The,School Project Geophysics' will be created to bring geophysical themes and results of scientific research into schools. One Day- or one Week-Workshops will help to publish geophysical contents in close cooperation with Physics - and Geography - teachers.\\Hands-on experiments (for advanced pupils) like refraction-Seismics or Magnetic measurements will lead students closer to scientific work and will help to establish personal interests in Earthsciences. Working with personally produced datasets will show the basics of inversion theory and point out the difficulties in creating models. Boundaries of data interpretation (the plurality of variables needed) will teach the school children to see scientific and statistic predictions and declarations more criticaly. Animations and Videos will present global examples (for example of volcanoes or Earthquakes) and lead over to regional sites. Excursions to these sites will help to show fieldwork methods and its problems and will convince to take a different look on topography and landscapes.\\All necessary utilities (Animations, Videos, Pictures and foils) will be offered to teachers in an online-data base which will be installed and managed by the project. Teachers and pupils might get easily into contact with Scientists to discuss geoscientific items. Further on extensions to geographic

  18. Water Detection Response Team Geophysics Element Case Histories

    DTIC Science & Technology

    1990-09-01

    34 on the surface by conducting one or more types of geophysical tests at that point. In the ideal case, the aquifer thickness and water quality would...The Geophysics Element has been deployed to participate in several major military exercises. Case historics of the Geophysics Element involvement in...ber who will advise the well drillers and reinterpret the geophysical survey results on the basis of drilling results, if necessary. This operating

  19. New geophysical models of Palmer Deep crustal structure

    NASA Astrophysics Data System (ADS)

    Yakymchuk, M. A.; Levashov, S. P.; Korchagin, I. N.; Bachmutov, V. G.; Solovyov, V. D.

    2009-04-01

    The 2004 (9th) and 2006 (11th) Ukrainian Antarctic expeditions acquired new geoelectrical data (‘short-impulse electromagnetic field formation' - FSPEF, and ‘vertical electric-resonance sounding' - VERS) along profiles across Drake Passage and along Bransfield Strait, Antarctic Peninsula, with the aim of studying the crustal structure of these features down to depths of >30 km. The sounding on this depth in Antarctic region was the first experience of deep modification of the VERS method using. Modelling experience of deep crustal structure by geophysical data with VERS method shows that there is a possibility to investigate the fluid regime, tectonic disturbances and crush zones in basement and local places of submarine volcanic activity too. This technology also gives a possibility to efficiently divide the cross-section on separate stratigraphic subsections in the sounding site and to determine its depth with high accuracy (Levashov et al., 2003; Levashov et al., 2007). Geophysical surveys enabled to yield new data set with information about Drake Passage and Palmer Deep inner crustal structure on broad continental margin of Antarctic Peninsula. Palmer Deep is located on continental (Pacific) shelf of the Antarctic Peninsula near Anvers Island and consists of three deep basins with depths from 1200м to 1500м. These basins were part of glacial outlet during glaciation's period (Rebesco et al., 1998). Geoelectrical models of Palmer Deep crustal structure along three profiles were built on the sounding data in separate points of continental shelf. Heterogeneity of Palmer Deep earth's crust obtained from VERS data modelling testified to processes of tectonic transformations of internal shelf structures. Tectonic factor explains some conformities of the most recent glaciomarine sediments and glacial streams forming during recent shelf-wide glaciations. New information about sediment distribution and inner crustal structure has an important value for searching

  20. Earth Observation

    NASA Image and Video Library

    2014-06-14

    Earth Observation taken during a day pass by the Expedition 40 crew aboard the International Space Station (ISS). Folder lists this as: Eastern half of US, sun glint, Texas, Maryland, Mississippi river, Great Lakes.

  1. Earth Observation

    NASA Image and Video Library

    2014-08-19

    Earth Observation taken during a night pass by the Expedition 40 crew aboard the International Space Station (ISS). Folder lists this as: Amazing Aurora. A docked Soyuz spacecrat is also visible in foreground.

  2. Earth Observation

    NASA Image and Video Library

    2014-08-09

    Earth Observation taken during a night pass by the Expedition 40 crew aboard the International Space Station (ISS). Folder lists this as: Middle East. Docked Soyuz and Progress spacecraft also visible.

  3. Earth Observation

    NASA Image and Video Library

    2014-08-09

    Earth Observation taken during a night pass by the Expedition 40 crew aboard the International Space Station (ISS). Folder lists this as: Middle East. The Space Station Remote Manipulator System (SSRMS) arm is also visible.

  4. Earth Observation

    NASA Image and Video Library

    2014-06-14

    Earth observation taken during a day pass by the Expedition 40 crew aboard the International Space Station (ISS). Folder lists this as: Phenomenon over Northern Russia - 4 (plus Europe pass). Distant and hazy Moon is visible.

  5. Earth observation

    NASA Image and Video Library

    2014-08-27

    Earth Observation taken during a night pass by the Expedition 40 crew aboard the International Space Station (ISS). Folder lists this as: Aurora. Part of Space Station Remote Manipulator System (SSRMS) arm is visible.

  6. Earth Observation

    NASA Image and Video Library

    2014-06-12

    Earth Observation taken during a day pass by the Expedition 40 crew aboard the International Space Station (ISS). Folder lists this as: Moon, Japan, Kamchatka with a wild cloud. Part of a solar array is also visible.

  7. Earth Observation

    NASA Image and Video Library

    2014-06-27

    Earth Observation taken during a day pass by the Expedition 40 crew aboard the International Space Station (ISS). Part of Space Station Remote Manipulator System (SSRMS) is visible. Folder lists this as: the Middle East, Israel.

  8. Earth Observation

    NASA Image and Video Library

    2014-07-03

    Earth Observation (sunrise over horizon) taken during a day pass by the Expedition 40 crew aboard the International Space Station (ISS). Docked Soyuz and Progress spacecraft are visible in foreground.

  9. Earth Observation

    NASA Image and Video Library

    2014-06-14

    Earth observation taken during a day pass by the Expedition 40 crew aboard the International Space Station (ISS). Folder lists this as: Phenomenon over Northern Russia - 1 of 2. Hazy and distant Moon is visible.

  10. Earth Observation

    NASA Image and Video Library

    2014-07-25

    Earth Observation taken during a day pass by the Expedition 40 crew aboard the International Space Station (ISS). Folder lists this as: United States - possible poor camera settings. Docked Soyuz spacecraft is also visible in foreground.

  11. Earth Science

    NASA Image and Video Library

    1992-07-18

    Workers at Launch Complex 17 Pad A, Kennedy Space Center (KSC) encapsulate the Geomagnetic Tail (GEOTAIL) spacecraft (upper) and attached payload Assist Module-D upper stage (lower) in the protective payload fairing. GEOTAIL project was designed to study the effects of Earth's magnetic field. The solar wind draws the Earth's magnetic field into a long tail on the night side of the Earth and stores energy in the stretched field lines of the magnetotail. During active periods, the tail couples with the near-Earth magnetosphere, sometimes releasing energy stored in the tail and activating auroras in the polar ionosphere. GEOTAIL measures the flow of energy and its transformation in the magnetotail and will help clarify the mechanisms that control the imput, transport, storage, release, and conversion of mass, momentum, and energy in the magnetotail.

  12. Discover Earth

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Discover Earth is a NASA-funded project for teachers of grades 5-12 who want to expand their knowledge of the Earth system, and prepare to become master teachers who promote Earth system science in their own schools, counties, and throughout their state. Participants from the following states are invited to apply: Connecticut, Delaware, Maine, Maryland, Massachusetts, New Hampshire, New Jersey, New York, Pennsylvania, Rhode Island, Vermont, and Washington, DC. Teachers selected for the project participate in a two-week summer workshop conducted at the University of Maryland, College Park; develop classroom-ready materials during the workshop for broad dissemination; conduct a minimum of two peer training activities during the coming school year; and participate in other enrichment/education opportunities as available and desired. Discover Earth is a team effort that utilizes expertise from a range of contributors, and balances science content with hands-on classroom applications.

  13. Earth Observation

    NASA Image and Video Library

    2014-05-31

    Earth Observation taken during a day pass by the Expedition 40 crew aboard the International Space Station (ISS). Folder lists this as: CEO - Arena de Sao Paolo. View used for Twitter message: Cloudy skies over São Paulo Brazil

  14. Earth Observation

    NASA Image and Video Library

    2013-08-03

    Earth observation taken during day pass by an Expedition 36 crew member on board the International Space Station (ISS). Per Twitter message: Perhaps a dandelion losing its seeds in the wind? Love clouds!

  15. Earth Science

    NASA Image and Video Library

    1990-10-24

    Solar Vector Magnetograph is used to predict solar flares, and other activities associated with sun spots. This research provides new understanding about weather on the Earth, and solar-related conditions in orbit.

  16. Earth Observation

    NASA Image and Video Library

    2013-07-26

    Earth observation taken during day pass by an Expedition 36 crew member on board the International Space Station (ISS). Per Twitter message: Never tire of finding shapes in the clouds! These look very botanical to me. Simply perfect.

  17. Earth Observation

    NASA Image and Video Library

    2013-08-20

    Earth observation taken during day pass by an Expedition 36 crew member on board the International Space Station (ISS). Per Twitter message: Looking southwest over northern Africa. Libya, Algeria, Niger.

  18. Earth Observation

    NASA Image and Video Library

    2014-06-12

    ISS040-E-010889 (12 June 2014) --- One of the Expedition 40 crew members aboard the Earth-orbiting International Space Station recorded this image of the Strait of Gibraltar, showing parts of Morocco and Spain, on June 12, 2014.

  19. Earth Observation

    NASA Image and Video Library

    2014-06-14

    ISS040-E-011996 (14 June 2014) --- One of the Expedition 40 crew members aboard the Earth-orbiting International Space Station recorded this image of the Strait of Gibraltar, showing parts of Morocco and Spain, on June 14, 2014.

  20. Earth Observation

    NASA Image and Video Library

    2014-07-01

    Earth Observation taken during a day pass by the Expedition 40 crew aboard the International Space Station (ISS). File lists this as: tropical storm over Atlantic. Docked Soyuz spacecraft is also visible.