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Cns Connections, Winter 2006-07, University Of Northern Iowa. College Of Natural Sciences. Jan 2006

Cns Connections, Winter 2006-07, University Of Northern Iowa. College Of Natural Sciences.

CNS Connections

Inside this issue:

-- Message from the Dean
-- Mini-robots duel in sumo competition
-- Earth Science offers B.S. in air quality
-- College News
-- Biology prof helps test method to reduce erosion
-- Title II grants fund CNS science education projects
-- Update from the Centers
-- Change of address for Computer Science
-- Carver grants strengthen CNS programs
-- Partnership for Goods starts at UNI
-- Faculty and Student Research Highlights
-- Ensuring a bright future for UNI
-- Alumni News
-- CNS Advisory Board


Spectral Analysis Of Ground Penetrating Radar Response To Thin Sedimentary Layers, Swagata Guha, Sarah E. Kruse, E. E. Wright, U. E. Kruse Dec 2005

Spectral Analysis Of Ground Penetrating Radar Response To Thin Sedimentary Layers, Swagata Guha, Sarah E. Kruse, E. E. Wright, U. E. Kruse

Geology Faculty Publications

Ground penetrating radar (GPR) systems utilized in studies of sedimentary deposits generate wavelengths (tens of centimeters) that are commonly much longer than the thickness of bedding (often millimeters to centimeters) within the target strata. Where this is the case, radar profiles represent interference patterns. Simple models of radar response to sequences of thin beds such as those found in coastal deposits show potentially detectable spectral shifts toward higher frequencies in radar returns. Spectral analysis of radar data over barrier beach deposits at Waites Island, South Carolina, shows that returns from packages with heavy mineral laminations are shifted toward higher frequencies …


Relationship Between Fault Zone Architecture And Groundwater Compartmentalization In The East Tintic Mining District, Utah, Sandra Myrtle Conrad Hamaker Nov 2005

Relationship Between Fault Zone Architecture And Groundwater Compartmentalization In The East Tintic Mining District, Utah, Sandra Myrtle Conrad Hamaker

Theses and Dissertations

The Eureka Lilly fault zone provides an impermeable barrier for groundwater flow in the East Tintic mining district. The fault zone separates two distinct groundwaters that have different temperatures, compositions, and potentiometric surfaces. The damage zone of the fault is an extensive network of interconnected open fractures and fault intersections that provide conduits for groundwater flow in otherwise impermeable units. The fault core breccia has been re-cemented and mineralized, which eliminates porosity in the rock by creating a thick impermeable zone, which has compartmentalized groundwaters across the fault zone. The compartmentalization of groundwater shows that fault zone variability (from strain …


Geodetic Gps Measurements In South Iceland: Strain Accumulation And Partitioning In A Propagating Ridge System, P. C. Lafemina, Timothy H. Dixon, R. Malservisi, T. Arnadottir, E. Sturkell, F. Sigmundsson, P. Einarsson Nov 2005

Geodetic Gps Measurements In South Iceland: Strain Accumulation And Partitioning In A Propagating Ridge System, P. C. Lafemina, Timothy H. Dixon, R. Malservisi, T. Arnadottir, E. Sturkell, F. Sigmundsson, P. Einarsson

School of Geosciences Faculty and Staff Publications

GPS observations in south Iceland between 1994 and 2003 are compared with two-dimensional elastic half-space and viscoelastic coupling models for two parallel rift zones, representing the Western and Eastern volcanic zones (WVZ, EVZ). GPS data from the Hreppar block, between the WVZ and EVZ, fit a rigid block model within uncertainties. Spreading rates across the WVZ increase from 2.6 ± 0.9 mm/yr in the northeast to 7.0 ± 0.4 mm/yr in the southwest. Conversely, spreading rates in the EVZ decrease from 19.0 ± 2.0 mm/yr in the northeast to 11.0 ± 0.8 mm/yr in the southwest, the direction of ridge …


Geologic Map Of The Golden Throne Quadrangle, Wayne And Garfield Counties, Utah, Daniel H. Martin Sep 2005

Geologic Map Of The Golden Throne Quadrangle, Wayne And Garfield Counties, Utah, Daniel H. Martin

Theses and Dissertations

The Golden Throne Quadrangle is located within Capitol Reef National Park, south-central Utah. Geologic mapping of this 1:24,000 scale 7.5 minute quadrangle began in 2003 as the National Parks Service desired to have geologic maps at this scale produced within the park. Stratigraphically, ten bedrock formations and ten Quaternary deposits are exposed within the Golden Throne Quadrangle. Geologic formations range in age from Permian to Jurassic. This map contains details not included on previous geologic maps including; the members of the Carmel, Chinle, and Moenkopi Formations. Additionally, the Page Sandstone is herein mapped as an independent unit. Structurally the Golden …


A Geodetic Investigation Of Ground Deformation At Yucca Mountain, Southern Nevada, Emma Mccaughey Aug 2005

A Geodetic Investigation Of Ground Deformation At Yucca Mountain, Southern Nevada, Emma Mccaughey

Publications (YM)

The data from 28 continuous BARGEN GPS stations in the Yucca Mountain region were processed for January 2000 to June 2004. The data have been processed independently using both the GIPSY and GAMIT software packages for quality assurance purposes, yielding an RMS of velocity differences between the solutions of 0.06 mm/yr for the east and 0.10 mm/yr for the north. The velocity solution for the local Yucca Mountain network has a relatively smooth signal showing NW-trending rightlateral shear. The magnitude of the velocity contrast across the local network, from east to west, is 0.95 ± 0.04 mm/yr. The GPS results …


Effects Of Hurricane Fault Architecture On Groundwater Flow In The Timpoweap Canyon Of Southwestern, Utah, Sarah J. Dutson Jul 2005

Effects Of Hurricane Fault Architecture On Groundwater Flow In The Timpoweap Canyon Of Southwestern, Utah, Sarah J. Dutson

Theses and Dissertations

Hydrogeologically important features of fault zones include undamaged country rock, the damage zone, and the core zone. Fault cores generally have low porosity and permeability, and often act as a barrier to groundwater flow. The damage zone, by contrast, consists of small faults and fracture networks, which can act as conduits. Timpoweap Canyon near Hurricane, Utah has superb exposures of the fault core and damage zone of the Hurricane Fault. Also within the canyon, springs discharge from the damage zone into the Virgin River, providing an ideal natural laboratory for the study of groundwater discharge from a fault zone. The …


Upper Mantle Reflectivity Beneath An Intracratonic Basin: Insights Into The Behavior Of The Mantle Beneath Illinois Basin., Maxwell Sunday Okure Jun 2005

Upper Mantle Reflectivity Beneath An Intracratonic Basin: Insights Into The Behavior Of The Mantle Beneath Illinois Basin., Maxwell Sunday Okure

Theses and Dissertations

Reflectivity images of the lower crust and uppermost mantle beneath the Illinois basin have been derived from reprocessing of several hundred kilometers of industry seismic reflection data using extended vibroseis recorrelation. The recorrelation was based on extending an originally 4-s correlated record, acquired with a 16-s sweep from 14 to 126 Hz, to the absolute limit of the full 20 s (~70 km) listening travel time. The reconstructed bandwidth includes frequency components suitable for imaging structures from signals received from both sedimentary basin reflectors and those received from reflectors in the deep crust and upper mantle. Mantle and sub-Moho reflectors …


A Uintan (Late Middle Eocene) Flora And Fauna From The Uinta Basin, Utah, Stephen Dee Sandau Mar 2005

A Uintan (Late Middle Eocene) Flora And Fauna From The Uinta Basin, Utah, Stephen Dee Sandau

Theses and Dissertations

Late Middle Eocene time marks one of the most dynamic periods of the Paleogene in the western interior of North America. Analysis of an extensive, new collection of plant, invertebrate, and vertebrae fossils from the Uinta Formation in the Uinta Basin, south of Myton, Utah, USA, provides evidence of environmental change. Paleobotanical specimens are preserved in late stage Uinta Lake sediments and coarse-grained fluvial sediments which are stratigraphically 650 to 660 m above the Green River Formation. Deposition rates estimates of 18 to 55 cm/kyr, for Uinta Lake sediments in the Uinta Basin suggest a period of 1.18 Ma to …


A Conceptual Model Of Groundwater Flow At The Midway, Utah Fish Hatchery As Constrained By Geochemical, Physical Hydrogeological, And Geophysical Methods, Camille Durrant Mar 2005

A Conceptual Model Of Groundwater Flow At The Midway, Utah Fish Hatchery As Constrained By Geochemical, Physical Hydrogeological, And Geophysical Methods, Camille Durrant

Theses and Dissertations

In addition to a loss of potential revenues from Utah's $393 million sport fishing industry, the state expends millions of dollars every year on costs associated with whirling disease mitigation and prevention. A state fish hatchery at Midway, Utah was closed when the shallow unconfined aquifer being used for fish culture by spring discharge was deemed to be contaminated by whirling disease. An alternative water source may exist in a confined aquifer below this contaminated unconfined aquifer. However, the complex hydrostratigraphy presents a challenge in determining if this source is a viable resource for fish culture. Geological, physical, chemical, geophysical, …


Paleoproterozoic High-Sulfidation Mineralization In The Tapajo´S Gold Province, Amazonian Craton, Brazil: Geology, Mineralogy, Alunite Argon Age, And Stable-Isotope Constraints, Caetano Juliani, Robert O. Rye, Carmen M.D. Nunes, Lawrence W. Snee, Rafael H. Corrêa Silva, Lena V.S. Monteiro, Jorge S. Bettencourt, Rainer Neumann, Arnaldo Alcover Neto Jan 2005

Paleoproterozoic High-Sulfidation Mineralization In The Tapajo´S Gold Province, Amazonian Craton, Brazil: Geology, Mineralogy, Alunite Argon Age, And Stable-Isotope Constraints, Caetano Juliani, Robert O. Rye, Carmen M.D. Nunes, Lawrence W. Snee, Rafael H. Corrêa Silva, Lena V.S. Monteiro, Jorge S. Bettencourt, Rainer Neumann, Arnaldo Alcover Neto

Geochemistry of Sulfate Minerals: A Tribute to Robert O. Rye

The Brazilian Tapajós gold province contains the first evidence of high-sulfidation gold mineralization in the Amazonian Craton. The mineralization appears to be in large nested calderas. The Tapajós–Parima (or Ventuari–Tapajo´ s) geological province consists of a metamorphic, igneous, and sedimentary sequence formed during a 2.10 to 1.87 Ga ocean ̶ continent orogeny. The high-sulfidation mineralization with magmatic-hydrothermal alunite is related to hydrothermal breccias hosted in a rhyolitic volcanic ring complex that contains granitic stocks ranging in age from 1.89 to 1.87 Ga. Cone-shaped hydrothermal breccias, which flare upward, contain vuggy silica and have an overlying brecciated cap of massive silica; …


Geologic Map And Topographic Profile Of The Newark Quadrangle, Nebraska, Steven M. Condon Jan 2005

Geologic Map And Topographic Profile Of The Newark Quadrangle, Nebraska, Steven M. Condon

United States Geological Survey: Publications

Newark Quadrangle, Nebraska


Geologic Map And Topographic Profile Of The Elm Creek West Quadrangle, Nebraska, Steven M. Condon Jan 2005

Geologic Map And Topographic Profile Of The Elm Creek West Quadrangle, Nebraska, Steven M. Condon

United States Geological Survey: Publications

Geologic Map and Topographic Profile of the Elm Creek West Quadrangle, Nebraska


Geologic Studies Of The Platte River, South-Central Nebraska And Adjacent Areas—Geologic Maps, Subsurface Study, And Geologic History, Steven M. Condon Jan 2005

Geologic Studies Of The Platte River, South-Central Nebraska And Adjacent Areas—Geologic Maps, Subsurface Study, And Geologic History, Steven M. Condon

United States Geological Survey: Publications

The Platte River of south-central Nebraska was studied at three scales to place the river in its geological context and to trace its evolution through geologic time. At the largest scale the Elm Creek West and the Newark 7.5 minute quadrangles were mapped. These quadrangles are located just west and just east of Kearney and serve to illustrate the main geomorphic elements of the present Platte River Valley. The central elements of the quadrangles are the Platte River channels, islands, and bottomlands, which are flanked by terraces that step up away from the river to the north and south. Significant …


Sulfur And Oxygen Isotopic Record In Sulfate And Sulfide Minerals Of Early, Deep, Pre-Main Stage Porphyry Cu–Mo And Late Main Stage Base-Metal Mineral Deposits, Butte District, Montana, C.W. Field, L. Zhang, J.H. Dilles, Robert O. Rye, M.H. Reed Jan 2005

Sulfur And Oxygen Isotopic Record In Sulfate And Sulfide Minerals Of Early, Deep, Pre-Main Stage Porphyry Cu–Mo And Late Main Stage Base-Metal Mineral Deposits, Butte District, Montana, C.W. Field, L. Zhang, J.H. Dilles, Robert O. Rye, M.H. Reed

Geochemistry of Sulfate Minerals: A Tribute to Robert O. Rye

Typical porphyry-type Cu–Mo mineralization occupies two connected domal centers, the eastern Pittsmont and western Anaconda domes, that predate and largely underlie the well-known, throughgoing, Main Stage polymetallic veins of Butte. Among the sulfur-bearing minerals recovered from deep drill core of this early pre-Main Stage hydrothermal assemblage are anhydrite, chalcopyrite, pyrite, and molybdenite in veinlets bordered by K-silicate alteration, and pyrite from slightly younger quartz–pyrite veinlets with dgray-sericiticT alteration selvages. The ranges of δ34S values for minerals of the K-silicate assemblage are 9.8–18.2%◦ for anhydrite (n=23 samples), 3.0%◦ to 4.7%◦ for molybdenite (n=6), 0.4%◦ to 3.4%◦ for pyrite (n=19), …


Chromian Spinel–Olivine Phase Chemistry And The Origin Of Primitive Basalts Of The Southern Washington Cascades, Diane R. Smith, W. P. Leeman Jan 2005

Chromian Spinel–Olivine Phase Chemistry And The Origin Of Primitive Basalts Of The Southern Washington Cascades, Diane R. Smith, W. P. Leeman

Earth and Environmental Geosciences Faculty Research

Geochemically diverse basalts occur in an ~160-km-wide transect that stretches across the Quaternary southern Washington Cascades (SWC) volcanic arc. Two fundamental groups of SWC basalts can be identified on the basis of major and trace element chemistry. On primitive mantle-normalized “spidergrams”, Group I lavas resemble within-plate basalts, whereas Group II lavas exhibit chemical characteristics (e.g., Nb, Ta, and Ti depletions) typical of subduction-related magmas. The primitive nature of many SWC basalts is indicated by their high MgO (>6.5 wt.%, up to 9.5 wt.%), Ni (>85 ppm) and Cr (>180 ppm) contents. Electron microprobe analyses of olivine–spinel pairs …


Quantitative Clay Mineralogy Of Several Louisiana Soils, Johan Forsman Jan 2005

Quantitative Clay Mineralogy Of Several Louisiana Soils, Johan Forsman

LSU Master's Theses

A method was developed to simplify the approach to obtaining a better quantitative representation (QR) of complex clay mineral assemblages by XRD analysis. The method has eight steps: 1) preparation of samples with preferred orientation; 2) qualitative identification of phases; 3) peak decomposition to obtain precise locations of individual peaks contained within broad diffraction bands; 4) creation of a library of theoretical XRD patterns by modeling of one-dimensional XRD patterns; 5) selection of experimental library patterns; 6) employing the LINEST function found in common spreadsheet software to fit library patterns to experimental patterns; 7) evaluation of results to determine needed …


New Stratigraphic Subdivision, Depositional Environment, And Age Estimate For The Upper Cretaceous Djadokhta Formation, Southern Ulan Nur Basin, Mongolia, Demberelyin Dashzeveg, Lowell Dingus, David B. Loope, Carl C. Swisher Iii, Togtokh Dulam, Mark R. Sweeney Jan 2005

New Stratigraphic Subdivision, Depositional Environment, And Age Estimate For The Upper Cretaceous Djadokhta Formation, Southern Ulan Nur Basin, Mongolia, Demberelyin Dashzeveg, Lowell Dingus, David B. Loope, Carl C. Swisher Iii, Togtokh Dulam, Mark R. Sweeney

Department of Earth and Atmospheric Sciences: Faculty Publications

Studies of key and newly discovered sections of the Upper Cretaceous Djadokhta Formation along the southern margin of the Ulan Nur Basin allow a new subdivision based on lithology. The formation and its members were mapped at both Bayn Dzak, an area that includes the Flaming Cliffs, and Tugrugyin Shireh, an area about 50 km to the northwest of Bayn Dzak. Stratigraphic sections at both localities were remeasured. The considerably enlarged formation comprises a lower Bayn Dzak Member, dominated by moderate reddish orange sands with subordinate mudstone units, and an upper Tugrugyin Member, composed of pale orange to light gray …


Geosciences Newsletter - 2004, Department Of Geosciences Nov 2004

Geosciences Newsletter - 2004, Department Of Geosciences

Geological and Environmental Sciences News

Vol. 1, No. 29

  • Mohamed Sultan, Chairperson
  • Faculty News
  • Emeriti News
  • Department News
  • Graduate Student News
  • Awards & Graduations
  • Alumni News
  • Field Trips
  • Outstanding Alumni Academy
  • Special Honor
  • New Faces in the Geosciences


Geodetic And Sconstraints On Some Seismogenic Zone Processes In Costa Rica, Edmundo Norabuena, Timothy H. Dixon, Susan Schwartz, Heather Deshon, Andrew Newman, Marino Protti, Victor Gonzalez, Leroy Dorman, Ernst R. Flueh, Paul Lundgren, Fred Pollitz, Dan Sampson Nov 2004

Geodetic And Sconstraints On Some Seismogenic Zone Processes In Costa Rica, Edmundo Norabuena, Timothy H. Dixon, Susan Schwartz, Heather Deshon, Andrew Newman, Marino Protti, Victor Gonzalez, Leroy Dorman, Ernst R. Flueh, Paul Lundgren, Fred Pollitz, Dan Sampson

School of Geosciences Faculty and Staff Publications

New seismic and geodetic data from Costa Rica provide insight into seismogenic zone processes in Central America, where the Cocos and Caribbean plates converge. Seismic data are from combined land and ocean bottom deployments in the Nicoya peninsula in northern Costa Rica and near the Osa peninsula in southern Costa Rica. In Nicoya, inversion of GPS data suggests two locked patches centered at 14 ± 2 and 39 ± 6 km depth. Interplate microseismicity is concentrated in the more freely slipping intermediate zone, suggesting that small interseismic earthquakes may not accurately outline the updip limit of the seismogenic zone, the …


An Unusually Large Aulocopella Winnipegensis And Associated Demosponges From The Upper Ordovician Beaverfoot Formation, Southeastern British Columbia, J. Keith Rigby, Paul A. Johnston Aug 2004

An Unusually Large Aulocopella Winnipegensis And Associated Demosponges From The Upper Ordovician Beaverfoot Formation, Southeastern British Columbia, J. Keith Rigby, Paul A. Johnston

Faculty Publications

An unusually large specimen of the rare digitate to bladed Aulocopella winnipegensis Rauff and three relatively normal sized specimens of ashtray-shaped Hudsonospongia? sp. constitute the first record of demosponges from the Upper Ordovician Beaverfoot Formation in southeastern British Columbia and the first record of these taxa from western Canada. Gross form and canal structure are well preserved, but dolomitization and (or) coarse microsphaeroidal silicification have obliterated spicules and other structural details. We interpret these sponges as epifaunal recliners, without means of attachment to the substrate, a life mode rarely encountered in the modern sponge biota.


Accuracy Of Neural Network Classifiers In Humid Tropical Areas, Genong Yu Aug 2004

Accuracy Of Neural Network Classifiers In Humid Tropical Areas, Genong Yu

All-Inclusive List of Electronic Theses and Dissertations

This research develops a better understanding of the use of neural networks in the context of tropical land cover characterization using multiple scale remotely sensed data. Results of the research contributed to developing a robust neural network classifier suitable to use for humid tropical land cover classification in areas such as Altamira, Brazil. Research was focused upon the following: (1) performance ofneural networks with different ancillary data- such as DEM (digital elevation model) and its derivatives; (2) effect of spatial scale on neural network classifiers using remote sensing data from IKONOS, Landsat TM, ASTER, and MODIS; (3) accuracy of neural …


Visualizing The Geology Of Lake Trout Spawning Sites: Northern Lake Michigan, Peter Dartnell, Peter Barnes, James V. Gardner, Kristen Lee May 2004

Visualizing The Geology Of Lake Trout Spawning Sites: Northern Lake Michigan, Peter Dartnell, Peter Barnes, James V. Gardner, Kristen Lee

Center for Coastal and Ocean Mapping

Geologists and biologists are working together to understand the links between lake floor geology (composition and shape) and the distribution of lake trout throughout their life cycle. Lake floor geology is one of the main factors determining where lake trout spawn, feed, and hide. In support of ongoing research to study Lake Michigan trout habitats, the U.S. Geological Survey in cooperation with the U.S. Army Corps of Engineers mapped the morphology of principle lake trout spawning sites. Using the Army Corps of Engineer's SHOALS airborne lidar (Light Detection and Ranging) system we mapped six regions in Northern Lake Michigan in …


Earth Day, Every Day, University Of South Alabama Jan 2004

Earth Day, Every Day, University Of South Alabama

Conservation/Energy Alternatives

Bibliography and photographs of a display of government documents from the University of South Alabama.


Late Albian Dinosaur Tracks From The Cratonic (Eastern) Margin Of The Western Interior Seaway, Nebraska, Usa, R. M. Joeckel, J. M. Cunningham, R. G. Corner, P. L. Phillips, G. A. Ludvigson Jan 2004

Late Albian Dinosaur Tracks From The Cratonic (Eastern) Margin Of The Western Interior Seaway, Nebraska, Usa, R. M. Joeckel, J. M. Cunningham, R. G. Corner, P. L. Phillips, G. A. Ludvigson

School of Natural Resources: Faculty Publications

No abstract provided.


The Cape Ann Plutonic Suite: A Field Trip For Petrology Classes, John B. Brady, John T. Cheney Jan 2004

The Cape Ann Plutonic Suite: A Field Trip For Petrology Classes, John B. Brady, John T. Cheney

Geosciences: Faculty Publications

Cape Ann, because of its proximity to Boston and many universities, has long been a focus of geologic study. Nineteenth century papers that consider mineralogy or petrology of Cape Ann rocks include Prescott (1839), Nichols (1856), Kimball (1860), Gregory (1862), Mudge (1862), Balch (1864), Cooke (1866, 1867), Knowlton (1867), Hyatt (1869, 1871a,b), Hunt (1871), Wadsworth (1878, 1882a,b, 1885), McDaniel (1884), Sears (1888, 1889, 1890a, 1891a,b, 1893a,b, 1894a,b, 1895, 1898), Shaler (1889), Pearce (1893), Penfield and Forbes (1896), and Washington (1898a,b,c, 1899a,b,c,d). More recent studies of note include Wright (1900), Clapp (1921), Warren and McKinstry (1924), Bowen and Schairer (1935), Palache …


40Ar/ 39Ar Ages Of Metamorphic Rocks From The Tobacco Root Mountains Region, Montana, John B. Brady, Dana N. Kovaric, John T. Cheney, Lisa J. Jacob, J. Toby King Jan 2004

40Ar/ 39Ar Ages Of Metamorphic Rocks From The Tobacco Root Mountains Region, Montana, John B. Brady, Dana N. Kovaric, John T. Cheney, Lisa J. Jacob, J. Toby King

Geosciences: Faculty Publications

Measurements of 60 single-grain, UV laser microprobe 40Ar/39Ar total gas ages for hornblende from metamorphic rocks of the Tobacco Root Mountains in southwest Montana yield a mean age of 1.71 ± 0.02 Ga. Measurements of 40Ar/39Ar step-heating plateau ages of three bulk hornblende samples from the Tobacco Root Mountains metamorphic rocks average 1.70 ± 0.02 Ga. We believe that these and the K/Ar or 40Ar/39Ar ages reported by previous workers are cooling ages from a 1.78 to 1.72 Ga, upper-amphibolite to granulite facies, regional metamorphism (Big Sky orogeny) that affected the northwestern portion of the Wyoming province, including the Tobacco …


Fine-Scale Structure Of The San Andreas Fault Zone And Location Of The Safod Target Earthquakes, C. Thurber, S. Roecker, H. Zhang, S. Baher, W. Ellsworth Jan 2004

Fine-Scale Structure Of The San Andreas Fault Zone And Location Of The Safod Target Earthquakes, C. Thurber, S. Roecker, H. Zhang, S. Baher, W. Ellsworth

United States Geological Survey: Staff Publications

We present results from the tomographic analysis of seismic data from the Parkfield area using three different inversion codes. The models provide a consistent view of the complex velocity structure in the vicinity of the San Andreas, including a sharp velocity contrast across the fault. We use the inversion results to assess our confidence in the absolute location accuracy of a potential target earthquake. We derive two types of accuracy estimates, one based on a consideration of the location differences from the three inversion methods, and the other based on the absolute location accuracy of ‘‘virtual earthquakes.’’ Location differences are …


Geogram 2003, David J. Keeling Editor, Wku Department Of Geography And Geology Oct 2003

Geogram 2003, David J. Keeling Editor, Wku Department Of Geography And Geology

Earth, Environmental, and Atmospheric Sciences Publications

No abstract provided.


Csrees School Of Natural Resources Comprehensive Five-Year Review Sep 2003

Csrees School Of Natural Resources Comprehensive Five-Year Review

School of Natural Resources: Documents and Reviews

No abstract provided.