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2014

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Articles 571 - 600 of 1044

Full-Text Articles in Earth Sciences

National Cave And Karst Research Institute Special Paper 2: Role Of Hydrogen Sulfide In The Formation Of Cave And Karst Phenomena In The Guadalupe Mountains And Western Delaware Basin, New Mexico And Texas, Douglas W. Kirkland Mar 2014

National Cave And Karst Research Institute Special Paper 2: Role Of Hydrogen Sulfide In The Formation Of Cave And Karst Phenomena In The Guadalupe Mountains And Western Delaware Basin, New Mexico And Texas, Douglas W. Kirkland

Environmental Sustainability Books

The National Cave and Karst Research Institute is pleased to publish Dr. Doug Kirkland’s monograph on the role of hydrogen sulfide on speleogenesis in the Guadalupe Mountains and western Delaware Basin. Dr. Kirkland’s work builds on his many years of research in southeastern New Mexico and west Texas, and provides the most comprehensive overview of cave and karst phenomena in the greater Delaware Basin region in almost 20 years. His work incorporates and summarizes decades of research by previous workers, combined with new ideas he has developed on speleogenesis in the Guadalupe Mountains. We feel confident that this publication will …


U.S. Drought Monitor, March 11, 2014, Richard Tinker Mar 2014

U.S. Drought Monitor, March 11, 2014, Richard Tinker

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for March 11, 2014 (3/11/14) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Corn, Soybeans, Hay, Cattle, Winter wheat.


Similar Resilience Attributes In Lakes With Different Management Practices, Didier L. Baho, Stina Drakare, Richard K. Johnson, Craig R. Allen, David G. Angeler Mar 2014

Similar Resilience Attributes In Lakes With Different Management Practices, Didier L. Baho, Stina Drakare, Richard K. Johnson, Craig R. Allen, David G. Angeler

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Liming has been used extensively in Scandinavia and elsewhere since the 1970s to counteract the negative effects of acidification. Communities in limed lakes usually return to acidified conditions once liming is discontinued, suggesting that liming is unlikely to shift acidified lakes to a state equivalent to pre-acidification conditions that requires no further management intervention. While this suggests a low resilience of limed lakes, attributes that confer resilience have not been assessed, limiting our understanding of the efficiency of costly management programs. In this study, we assessed community metrics (diversity, richness, evenness, biovolume), multivariate community structure and the relative resilience of …


Influence Of Introgression And Geological Processes On Phylogenetic Relationships Of Western North American Mountain Suckers (Pantosteus, Catostomidae), Peter J. Unmack, Thomas E. Dowling, Nina J. Laitinen, Carol L. Secor, Richard L. Mayden, Dennis K. Shiozawa, Gerald R. Smith Mar 2014

Influence Of Introgression And Geological Processes On Phylogenetic Relationships Of Western North American Mountain Suckers (Pantosteus, Catostomidae), Peter J. Unmack, Thomas E. Dowling, Nina J. Laitinen, Carol L. Secor, Richard L. Mayden, Dennis K. Shiozawa, Gerald R. Smith

Biological Sciences Faculty Research Publications

Intense geological activity caused major topographic changes in Western North America over the past 15 million years. Major rivers here are composites of different ancient rivers, resulting in isolation and mixing episodes between river basins over time. This history influenced the diversification of most of the aquatic fauna. The genus Pantosteus is one of several clades centered in this tectonically active region. The eight recognized Pantosteus species are widespread and common across southwestern Canada, western USA and into northern Mexico. They are typically found in medium gradient, middle-elevation reaches of rivers over rocky substrates. This study (1) compares molecular data …


Geology & Geography News, Georgia Southern University Mar 2014

Geology & Geography News, Georgia Southern University

Earth, Environment & Sustainability: News & Publications (2013-2021)

  • C.J. Jackson’s work featured in Coastal Currents


Base Metals Prospecting In Kagera Region, Tanzania Using Remote Sensing And Biogeochemistry Analytics, Thomas A. Woolman Mar 2014

Base Metals Prospecting In Kagera Region, Tanzania Using Remote Sensing And Biogeochemistry Analytics, Thomas A. Woolman

The Compass: Earth Science Journal of Sigma Gamma Epsilon

This paper explores the use of biogeochemistry as a means for conducting geological prospecting in search of economic grade anomalies of precious metals, base metals and rare earth elements. The use of randomized soil sampling for geostatistical coefficient calculations and aeromagnetic remote sensing systems in conjunction with biogeochemical prospecting for ferromagnetic elements is examined. The paper concludes that the evidence presented indicates that bioprospecting can be an extremely powerful economic geology tool for conducting rapid and cost effective micro-targeting mineral discovery.


An Applied Geophysical Detection And Subsequent Mitigation Of An Abandoned Well Casing Penetrating The Permian Hutchinson Salt At An Undisclosed Kansas Salt Mine, Kenneth R. Neuhauser, Daniel J. Redetzke Mar 2014

An Applied Geophysical Detection And Subsequent Mitigation Of An Abandoned Well Casing Penetrating The Permian Hutchinson Salt At An Undisclosed Kansas Salt Mine, Kenneth R. Neuhauser, Daniel J. Redetzke

The Compass: Earth Science Journal of Sigma Gamma Epsilon

A surface field survey, using a cesium magnetometer, successfully targeted the spatial location of an abandoned buried well casing. Surface excavation exposed the top of the well casing, but attempts to drill out the casing from the surface failed due to the difficulty of keeping the drill bit on-line with the casing. The casing was successfully sealed off by grouting through the ceiling and floor from within the mine.


Sigma Gamma Epsilon Student Research Poster Session, Geological Society Of America Meeting 2013, Denver, Colorado, Paula Even Mar 2014

Sigma Gamma Epsilon Student Research Poster Session, Geological Society Of America Meeting 2013, Denver, Colorado, Paula Even

The Compass: Earth Science Journal of Sigma Gamma Epsilon

The 2013 Sigma Gamma Epsilon Undergraduate Research (Poster Session) took place during the 2013 GSA Conference in Denver, CO. on Tuesday, 29 October 2013: 9:00 a.m. - 6:30 p.m. (Authors were present from 2 to 4 p.m. and 5:00 to 6:30 p.m.). Ninety-eight posters were presented. Sigma Gamma Epsilon awarded the Austin A. Sartin Best Poster Award to Brittney Klemm, a member of Eta Upsilon Chapter at the University of the Pacific in Stockton, CA. Sebastian Dirringer, a member of Theta Beta Chapter at the State University of New York in New Paltz, NY, was awarded the National Council Best …


Sigma Gamma Epsilon 2012-2013 W. A. Tarr Awards, Paula Even Mar 2014

Sigma Gamma Epsilon 2012-2013 W. A. Tarr Awards, Paula Even

The Compass: Earth Science Journal of Sigma Gamma Epsilon

The W. A. Tarr Award was first established in March 1949, to recognize outstanding students in the Earth Sciences. Qualifying criteria for the award are provided as well as a list of individuals who received this award for the 2012-2013 academic year.


Probabilistic Modeling Of Lava Flows: A Hazard Assessment For The San Francisco Volcanic Field, Arizona, Aleeza Harburger Mar 2014

Probabilistic Modeling Of Lava Flows: A Hazard Assessment For The San Francisco Volcanic Field, Arizona, Aleeza Harburger

USF Tampa Graduate Theses and Dissertations

This study serves as a first step towards a comprehensive hazard assessment for the San Francisco volcanic field in northern Arizona, which can be applied to local response plans and educational initiatives. The primary goal of this thesis is to resolve the conditional probability that, given a lava flow effusing from a new vent in the San Francisco volcanic field, it will inundate the city limits of Flagstaff. The spatial distribution of vents within the San Francisco volcanic field was analyzed in order to execute a lava flow simulation to determine the inundation hazard to Flagstaff. The Gaussian kernel function …


Cretaceous-Paleogene Dinoflagellate Biostratigraphy And The Age Of The Clayton Formation, Southeastern Missouri, Usa, Natalie R. Dastas, John A. Chamberlain Jr., Matthew P. Garb Mar 2014

Cretaceous-Paleogene Dinoflagellate Biostratigraphy And The Age Of The Clayton Formation, Southeastern Missouri, Usa, Natalie R. Dastas, John A. Chamberlain Jr., Matthew P. Garb

Publications and Research

Sedimentary deposits in Stoddard County, southeastern Missouri, reveal a K-Pg transition sequence represented by the uppermost Maastrichtian Owl Creek Formation and the Paleocene Clayton Formation. The Clayton Formation is characterized by a basal fossiliferous coquinite that contains reworked late Maastrichtian macrofossils. Dinoflagellate biostratigraphy is used to determine the age of the coquinite layer and specifically whether or not it is an end-K tsunamite deposit resulting from the Chicxulub impact event. Results indicate a mixed assemblage of late Maastrichtian and early Danian dinocysts within the basal coquinite of the Clayton Formation. Maastrichtian dinocyst taxa identified are Riculacysta amplexa, Pierceites pentagonus, Phelodinium …


Geology & Geography News, Georgia Southern University Mar 2014

Geology & Geography News, Georgia Southern University

Earth, Environment & Sustainability: News & Publications (2013-2021)

  • Study Abroad Opportunity to be offered Summer 2015


U.S. Drought Monitor, March 4, 2014, Brad Rippey Mar 2014

U.S. Drought Monitor, March 4, 2014, Brad Rippey

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for March 4, 2014 (3/4/14) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Corn, Soybeans, Hay, Cattle, Winter wheat.


Groundwater Flow Across Spatial Scales: Importance For Climate Modeling, Nir Krakauer, Haibin Li, Ying Fan Mar 2014

Groundwater Flow Across Spatial Scales: Importance For Climate Modeling, Nir Krakauer, Haibin Li, Ying Fan

Publications and Research

Current regional and global climate models generally do not represent groundwater flow between grid cells as a component of the water budget. We estimate the magnitude of between cell groundwater flow as a function of grid cell size by aggregating results from a numerical model of equilibrium groundwater flow run and validated globally. We find that over a broad range of cell sizes spanning that of state of the art regional and global climate models, mean between cell groundwater flow magnitudes scale with the reciprocal of grid cell length. We also derive this scaling a priori from a simple statistical …


Communicating The Science Of Igcp 591 To The Public, Lewandowski J. Katherine Mar 2014

Communicating The Science Of Igcp 591 To The Public, Lewandowski J. Katherine

Faculty Research and Creative Activity

Selling the broader impacts of science to funding agencies has become a necessity in a time when competition for grant money is high. While involving students in research is still important for maintaining a pipeline of trained scientists, the bar has been raised and it is increasingly incumbent on us to communicate to the public what is so important about our work. To be competitive in the search for funds, there must be a plan for the science funded to be disseminated to the public. The education and outreach plan for IGCP 591 attempts to appeal to this broader audience …


Ua66 Ogden College Of Science & Engineering Newsletter, Cheryl Stevens, Dean Mar 2014

Ua66 Ogden College Of Science & Engineering Newsletter, Cheryl Stevens, Dean

Ogden College of Science & Engineering Publications

No abstract provided.


Is Horizon Sampling More Powerful Than Depth Sampling?, Chris E. Johnson Mar 2014

Is Horizon Sampling More Powerful Than Depth Sampling?, Chris E. Johnson

Civil and Environmental Engineering - All Scholarship

No abstract provided.


Spatial Distribution Of Greenhouse Commercial Horticulture In Kenya And The Role Of Demographic, Infrastructure And Topo-Edaphic Factors, Faith Justus, Danlin Yu Mar 2014

Spatial Distribution Of Greenhouse Commercial Horticulture In Kenya And The Role Of Demographic, Infrastructure And Topo-Edaphic Factors, Faith Justus, Danlin Yu

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Greenhouse commercial horticulture in Kenya started more than two decades ago and has evolved to be a significant sector to the national economy. So far no studies have explored the spatial patterns and dynamics of the area under greenhouse cultivation. Google Earth archives alongside data from various portals provided an opportunity to study those farms' spatial distribution. The roles of selected topo-edaphic, infrastructure and demographics factors that might influence current location within sub-watersheds in central highlands of Kenya are also examined. Results reveal a non-uniform spread with two high clusters; one in the semi-Arid sub-watersheds 3AB shared by Kajiado and …


Umphlett Qci March 2014, Natalie Umphlett Mar 2014

Umphlett Qci March 2014, Natalie Umphlett

High Plains Regional Climate Center: Staff Publications

Highlights for the Basin

Temperature and Precipitation Anomalies

Mountain Snowpack

Agriculture

Tourism and Recreation

Missouri Basin Flood Outlook

U.S. Seasonal Drought Outlook


Lunar Cold Spots: Granular Flow Features And Extensive Insulating Materials Surrounding Young Craters, Joshua L. Bandfield, Eugenie Song, Paul O. Hayne, Brittany D. Brand, Rebecca R. Ghent, Ashwin R. Vasavada, David A. Paige Mar 2014

Lunar Cold Spots: Granular Flow Features And Extensive Insulating Materials Surrounding Young Craters, Joshua L. Bandfield, Eugenie Song, Paul O. Hayne, Brittany D. Brand, Rebecca R. Ghent, Ashwin R. Vasavada, David A. Paige

Geosciences Faculty Publications and Presentations

Systematic temperature mapping and high resolution images reveal a previously unrecognized class of small, fresh lunar craters. These craters are distinguished by near-crater deposits with evidence for lateral, ground-hugging transport. More distal, highly insulating surfaces surround these craters and do not show evidence of either significant deposition of new material or erosion of the substrate. The near-crater deposits can be explained by a laterally propagating granular flow created by impact in the lunar vacuum environment. Further from the source crater, at distances of ~10-100 crater radii, the upper few to 10s of centimeters of regolith appear to have been “fluffed-up” …


Detection Of An Ultra Low Velocity Zone Beneath Central Mexico With Pcp Waveform Modeling, David James Buckley Mar 2014

Detection Of An Ultra Low Velocity Zone Beneath Central Mexico With Pcp Waveform Modeling, David James Buckley

Physics

PcP phases from a Guatemalan earthquake recorded at Nevada stations of the International seismic network (IM) display evidence of anomalous seismic structure at the core-mantle boundary (CMB); in particular, pre- and post-cursor phases to PcP and ScP. The data is examined for evidence of an ultra-low velocity zone (ULVZ) by identifying and modeling precursors to PcP. Precursory arrivals to PcP may be generated by the interaction of PcP with a thin layer above the core-mantle boundary (CMB). One-dimensional modeling demonstrates that standard earth models of the core-mantle boundary, which lack ULVZ structure, cannot produce the observed PcP data. …


Mechanisms Of Soil Carbon Accrual And Storage In Bioenergy Cropping Systems, Lisa K. Tiemann, A. Stuart Grandy Mar 2014

Mechanisms Of Soil Carbon Accrual And Storage In Bioenergy Cropping Systems, Lisa K. Tiemann, A. Stuart Grandy

Faculty Publications

Annual row cropping systems converted to perennial bioenergy crops tend to accrue soil C, likely a function of increased root production and decreased frequency of tillage; however, very little is known about the mechanisms governing the accrual and stability of this additional soil C. To address this uncertainty, we assessed the formation and stability of aggregates and soil organic C (SOC) pools under switchgrass, giant miscanthus, a native perennial grass mix and continuous corn treatments in Michigan and Wisconsin soils differing in both texture and mineralogy. We isolated different aggregate size fractions, >2 mm, 0.5–2 mm, and <0.5 mm, using a procedure intended to minimize alterations to aggregate biological and chemical properties. We determined SOC, permanganate oxidizable C (POXC), and microbial activities (i.e. enzyme activities and soil respiration rates) associated with these aggregates. Soil type strongly influenced the trajectory of aggregate formation and stabilization with differences between sites in mean aggregate size, stability, SOC and microbial activity under perennial vs. corn cropping systems. At the Michigan site, soil microbial activities were highest in the >2 mm aggregates, …


Comparative Analysis Of Two Successive Vintages Of Cabernet Sauvignon Must And Pre-Barrel Wine From Two Distinct Soil Types, Jon Garret Page Mar 2014

Comparative Analysis Of Two Successive Vintages Of Cabernet Sauvignon Must And Pre-Barrel Wine From Two Distinct Soil Types, Jon Garret Page

Master's Theses

The objective of this study was to determine if there were significant statistical differences in the response variables of Cabernet Sauvignon must and pre-barreled wine analyzed from two vintages from two distinct soil types.

Research was conducted at California Polytechnic University, San Luis Obispo to examine the quantitative chemical analysis of 22 different response variables of Cabernet Sauvignon grapes. The same 22 variables were analyzed in must and pre-barreled wine samples harvested from both Calodo Clay Loam soil and Zaca Clay soil. The analyses were done at both California Polytechnic University, San Luis Obispo and Vinquiry Inc. Labs. The results …


Field And Model Study To Define Baseline Conditions Of Beached Oil Tar Balls Along Florida’S First Coast, Peter Bacopoulos, James David Lambert, Mary Hertz, Luis Montoya, Terry L. Smith Mar 2014

Field And Model Study To Define Baseline Conditions Of Beached Oil Tar Balls Along Florida’S First Coast, Peter Bacopoulos, James David Lambert, Mary Hertz, Luis Montoya, Terry L. Smith

Physics Faculty Research and Scholarship

Anecdotal data are currently the best data available to describe baseline conditions of beached oil tar balls on Florida’s First Coast beaches. This study combines field methods and numerical modeling to define a data-driven knowledge base of oil tar ball baseline conditions. Outcomes from the field study include an established methodology for field data collection and laboratory testing of beached oil tar balls, spatial maps of collected samples and analysis of the data as to transport/wash-up trends. Archives of the electronic data, including GPS locations and other informational tags, and collected samples are presented, as are the physical and chemical …


Receiver Function Constraints On Crustal Seismic Velocities And Partial Melting Beneath The Red Sea Rift And Adjacent Regions, Afar Depression, Cory A. Reed, Sattam Almadani, Stephen S. Gao, Ahmed A. Elsheikh, Solomon Cherie, Mohamed G. Abdel Salam, Allison K. Thurmond, Kelly H. Liu Mar 2014

Receiver Function Constraints On Crustal Seismic Velocities And Partial Melting Beneath The Red Sea Rift And Adjacent Regions, Afar Depression, Cory A. Reed, Sattam Almadani, Stephen S. Gao, Ahmed A. Elsheikh, Solomon Cherie, Mohamed G. Abdel Salam, Allison K. Thurmond, Kelly H. Liu

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The Afar Depression is an ideal locale for the investigation of crustal processes involved in the transition from continental rifting to oceanic spreading. To provide relatively high resolution images of the crust beneath the Red Sea rift (RSR) represented by the Tendaho graben in the Afar Depression, we deployed an array of 18 broadband seismic stations in 2010 and 2011. Stacking of about 2300 receiver functions from the 18 and several nearby stations along the ~200 km long array reveals an average crustal thickness of 22 ± 4 km, ranging from ~17 km near the RSR axis to 30 km …


Seismic Anisotropy And Mantle Flow Beneath The Northern Great Plains Of North America, Bin B. Yang, Stephen S. Gao, Kelly H. Liu, Ahmed A. Elsheikh, Awad A. Lemnifi, Hesham A. Refayee, Youqiang Yu Mar 2014

Seismic Anisotropy And Mantle Flow Beneath The Northern Great Plains Of North America, Bin B. Yang, Stephen S. Gao, Kelly H. Liu, Ahmed A. Elsheikh, Awad A. Lemnifi, Hesham A. Refayee, Youqiang Yu

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

A diverse set of tectonic features and the recent availability of high-quality broadband seismic data from the USArray and other stations on the northern Great Plains of North America provide a distinct opportunity to test different anisotropy-forming mechanisms. A total of 4138 pairs of well-defined splitting parameters observed at 445 stations show systematic spatial variations of anisotropic characteristics. Azimuthally invariant fast orientations subparallel to the absolute plate motion (APM) direction are observed at most of the stations on the Superior Craton and the southern Yavapai province, indicating that a single layer of anisotropy with a horizontal axis of symmetry is …


West Antarctic Surface Mass Balance: Do Synoptic Scale Modes Of Climate Contribute To Observed Variability?, Mclean Kent Carpenter Mar 2014

West Antarctic Surface Mass Balance: Do Synoptic Scale Modes Of Climate Contribute To Observed Variability?, Mclean Kent Carpenter

Theses and Dissertations

Western Antarctica has been experiencing significant warming for at least the past fifty years. While higher Net Surface Mass Balance (SMB) over West Antarctica during this period of warming is expected, SMB reconstructions from ice cores reveal a more complex pattern during the period of warming. The mechanisms giving rise to SMB variability over the West Antarctic Ice Sheet (WAIS) are not well understood due to lack of instrumental data. The Southern Annular Mode (SAM) and El Niño Southern Oscillation (ENSO) are believed to contribute to WAIS SMB variability but the assumption has not been rigorously tested. SMB during years …


Quantifying The Impact Of Atmospheric Deposition On The Biogeochemistry Of Fe And Al In The Upper Ocean: A Decade Of Collaboration With The Us Clivar-Co2 Repeat Hydrography Program, Maxime Grand, Clifton Buck, William Landing, Christopher Measures, Mariko Hatta, William Hiscock, Matthew Brown, Joseph Resing Mar 2014

Quantifying The Impact Of Atmospheric Deposition On The Biogeochemistry Of Fe And Al In The Upper Ocean: A Decade Of Collaboration With The Us Clivar-Co2 Repeat Hydrography Program, Maxime Grand, Clifton Buck, William Landing, Christopher Measures, Mariko Hatta, William Hiscock, Matthew Brown, Joseph Resing

Faculty Publications

The aerosol deposition of continental material and its partial dissolution in the surface ocean exerts an important control on the distribution of iron and other potentially limiting trace metal (TM) micronutrients in the open ocean. This dust deposition has implications for the regulation of global climate through the coupling of biolimiting TM cycles, marine productivity, and the global carbon cycle. Thus, it is important to determine the locations of dust deposition in the open ocean and to quantify the magnitude and subsequent dissolution of the dust. At present, there are too few dust deposition estimates and solubility measurements in the …


Geotraces: Changing The Way We Explore Ocean Chemistry, Robert F. Anderson, Edward Mawji, Gregory A. Cutter, Christopher I. Measures, Catherine Jeandel Mar 2014

Geotraces: Changing The Way We Explore Ocean Chemistry, Robert F. Anderson, Edward Mawji, Gregory A. Cutter, Christopher I. Measures, Catherine Jeandel

OES Faculty Publications

GEOTRACES is an international study of the marine biogeochemical cycles of trace elements and their isotopes (TEIs), designed by marine geochemists to accelerate TEI research under a global program. Combining ocean sections, process studies, data synthesis, and modeling, GEOTRACES will identify and quantify the processes that supply TEIs at ocean boundaries as well as the physical and biological processes that redistribute TEIs within and between ocean basins. Constraining processes that remove TEIs from the ocean will enable complete mass budgets to be generated. Anticipated beneficiaries of GEOTRACES products include scientists studying the sustained health of marine ecosystems and their sensitivity …


Nongeocentric Axial Dipole Field Behavior During The Mono Lake Excursion, Robert M. Negrini, Daniel T. Mccuan, Robert A. Horton, James D. Lopez, William S. Cassata, James E.T. Channell, Kenneth L. Verosub, Jeffrey R. Knott, Robert S. Coe, Joseph C. Liddicoat, Steven P. Lund, Larry V. Benson, Andrei M. Sarna-Wojcicki Mar 2014

Nongeocentric Axial Dipole Field Behavior During The Mono Lake Excursion, Robert M. Negrini, Daniel T. Mccuan, Robert A. Horton, James D. Lopez, William S. Cassata, James E.T. Channell, Kenneth L. Verosub, Jeffrey R. Knott, Robert S. Coe, Joseph C. Liddicoat, Steven P. Lund, Larry V. Benson, Andrei M. Sarna-Wojcicki

United States Geological Survey: Staff Publications

A new record of the Mono Lake excursion (MLE) is reported from the Summer Lake basin of Oregon, USA. Sediment magnetic properties indicate magnetite as the magnetization carrier and imply suitability of the sediments as accurate recorders of the magnetic field including relative paleointensity (RPI) variations. The magnitudes and phases of the declination, inclination, and RPI components of the new record correlate well with other coeval but lower resolution records from western North America including records from the Wilson Creek Formation exposed around Mono Lake. The virtual geomagnetic pole (VGP) path of the new record is similar to that from …