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Delayed Warming Hiatus Over The Tibetan Plateau, Wenling An, Shugui Hou, Yongyun Hu, Shuang-Ye Wu 2017 Nanjing University

Delayed Warming Hiatus Over The Tibetan Plateau, Wenling An, Shugui Hou, Yongyun Hu, Shuang-Ye Wu

Department of Earth, Environment and Sustainability Faculty Publications

A reduction in the warming rate for the global surface temperature since the late 1990s has attracted much attention and caused a great deal of controversy. During the same time period, however, most previous studies have reported enhanced warming over the Tibetan Plateau (TP). In this study we further examined the temperature trend of the TP and surrounding areas based on the homogenized temperature records for the period 1980–2014, we found that for the TP regions lower than 4000 m the warming rate has started to slow down since the late 1990s, a similar pattern consistent with the whole China …


Ground-Rupturing Earthquakes On The Northern Big Bend Of The San Andreas Fault, California, 800 A.D. To Present, Katherine Scharer, Ray J. Weldon II, Glenn Biasi, Ashley Streig, Thomas Fumal 2017 U.S. Geological Survey

Ground-Rupturing Earthquakes On The Northern Big Bend Of The San Andreas Fault, California, 800 A.D. To Present, Katherine Scharer, Ray J. Weldon Ii, Glenn Biasi, Ashley Streig, Thomas Fumal

Geology Faculty Publications and Presentations

Paleoseismic data on the timing of ground-rupturing earthquakes constrain the recurrence behavior of active faults and can provide insight on the rupture history of a fault if earthquakes dated at neighboring sites overlap in age and are considered correlative. This study presents the evidence and ages for 11 earthquakes that occurred along the Big Bend section of the southern San Andreas Fault at the Frazier Mountain paleoseismic site. The most recent earthquake to rupture the site was the Mw7.7–7.9 Fort Tejon earthquake of 1857. We use over 30 trench excavations to document the structural and sedimentological evolution of a small …


Unique Preservation Of Fossil Ghost Fish In The Green River Formation, Amanda L. Meacham 2017 Loma Linda University

Unique Preservation Of Fossil Ghost Fish In The Green River Formation, Amanda L. Meacham

Loma Linda University Electronic Theses, Dissertations & Projects

Two beds with unique fossil fish preservation occur within the predominantly evaporite-rich, fossil poor Angelo Member in the Green River Formation in Fossil Basin, Wyoming. These two beds, termed “Ghost Fish” beds, contain fossil fish that are two-dimensional carbonaceous compressions with no bone and detailed soft part preservation. These beds were measured and samples were collected from 8 quarries and 19 additional locations. Stratigraphic sections and fossil content were recorded at each quarry location. Analysis included XRD, stable isotope, XRF, TOC, and SEM analysis. Results were inputted into tables, graphs, and spatial maps to show trends, interpret the paleoenvironment, and …


Unusual Geologic Evidence Of Coeval Seismic Shaking And Tsunamis Shows Variability In Earthquake Size And Recurrence In The Area Of The Giant 1960 Chile Earthquake, M. Cisternas, E. Garrett, R. Wesson, T. Dura, Lisa L. Ely 2017 Pontificia Universidad Católica de Valparaíso

Unusual Geologic Evidence Of Coeval Seismic Shaking And Tsunamis Shows Variability In Earthquake Size And Recurrence In The Area Of The Giant 1960 Chile Earthquake, M. Cisternas, E. Garrett, R. Wesson, T. Dura, Lisa L. Ely

All Faculty Scholarship for the College of the Sciences

An uncommon coastal sedimentary record combines evidence for seismic shaking and coincident tsunami inundation since AD 1000 in the region of the largest earthquake recorded instrumentally: the giant 1960 southern Chile earthquake (Mw 9.5). The record reveals significant variability in the size and recurrence of megathrust earthquakes and ensuing tsunamis along this part of the Nazca-South American plate boundary. A 500-m long coastal outcrop on Isla Chiloé, midway along the 1960 rupture, provides continuous exposure of soil horizons buried locally by debris-flow diamicts and extensively by tsunami sand sheets. The diamicts flattened plants that yield geologically precise ages to correlate …


Seismic Azimuthal Anisotropy Beneath The Eastern United States And Its Geodynamic Implications, Bin B. Yang, Yunhua Liu, Haider Dahm, Kelly H. Liu, Stephen S. Gao 2017 Missouri University of Science and Technology

Seismic Azimuthal Anisotropy Beneath The Eastern United States And Its Geodynamic Implications, Bin B. Yang, Yunhua Liu, Haider Dahm, Kelly H. Liu, Stephen S. Gao

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Systematic spatial variations of anisotropic characteristics are revealed beneath the eastern U.S. using seismic data recorded between 1988 and 2016 by 785 stations. The resulting fast polarization orientations of the 5613 measurements are generally subparallel to the absolute plate motion (APM) and are inconsistent with the strike of major tectonic features. This inconsistency, together with the results of depth estimation using the spatial coherency of the splitting parameters, suggests a mostly asthenospheric origin of the observed azimuthal anisotropy. The observations can be explained by a combined effect of APM-induced mantle fabric and a flow system deflected horizontally around the edges …


A Quaternary Climate Record From A Uinta Mountains, Usa, Fen Core With Emphasis On Sediment Pyrolysis, Samuel Abraham Hillam 2017 Brigham Young University

A Quaternary Climate Record From A Uinta Mountains, Usa, Fen Core With Emphasis On Sediment Pyrolysis, Samuel Abraham Hillam

Theses and Dissertations

The northern slopes of the Uinta Mountains, Utah were previously glaciated and contain many landslides. The Tokewanna Landslide is very large and lacks Quaternary faults. Presumably, increased moisture was the failure trigger. A Quaternary climate record from a cored fen, developed in a small basin between hummocks, was reconstructed using sediment pyrolysis, biomass balance, and magnetic susceptibility. Pyrolysis is used to define Hydrogen Indices that are used to delineate wetter and drier conditions based on the kerogen type - Type III being drier, and Type II wetter. The data were matched to a time/depth curve and compared to other Uinta …


Lithology And Depositional Environments Of A Portion Of The Clays Ferry Formation (Middle And Upper Ordovician) Exposed At Silver Creek, Madison County, Kentucky, Autumn Murray, Walter S. Borowski 2017 Eastern Kentucky University

Lithology And Depositional Environments Of A Portion Of The Clays Ferry Formation (Middle And Upper Ordovician) Exposed At Silver Creek, Madison County, Kentucky, Autumn Murray, Walter S. Borowski

EKU Faculty and Staff Scholarship

We measure, describe, and interpret a carbonate stratigraphic section within the Clays Ferry Formation (Middle and Upper Ordovician) cropping out in Madison County, Kentucky (USGS Kirksville 7.5” quadrangle). Outcrops are exposed within the bed of Silver Creek along Ky 876 (Barnes Mill Road) from ~100 m downstream of where a bridge crosses the stream, then upstream and upsection for a distance of ~300 m over several sets of falls until bedrock exposure becomes sporadic to absent. We sampled the stratigraphic section at approximately half-meter intervals, also taking samples at lithology changes. We collected a total 18 samples, all of which …


Surficial Geology Of The Saybrook 7.5-Minute Quadrangle, Mclean County, Illinois, Usa, Ellyn S. Rickels, Andrew J. Stumpf, David H. Malone, William E. Shields 2017 Illinois State University

Surficial Geology Of The Saybrook 7.5-Minute Quadrangle, Mclean County, Illinois, Usa, Ellyn S. Rickels, Andrew J. Stumpf, David H. Malone, William E. Shields

Faculty Publications - Geography, Geology, and the Environment

This project involved the construction of a surficial (Quaternary) geologic map of part of McLean County, Illinois. The Saybrook 7.5-minute Quadrangle (scale 1:24,000) was the focus area. The quadrangle largely covers rural agricultural land, but also contains the small town of Saybrook. Multiple, major episodes of glaciation over the past 1,200,000 years have controlled the regional geologic history. The most recent (Wisconsin Episode) glaciation almost exclusively shaped the observed surficial geologic and geomorphic features in the quadrangle. Field observations, USDA soil survey data, private water well data, sparse stratigraphic borehole information, and LIDAR elevation data were used to construct the …


Calcite Twinning Strain Variations Across The Proterozoic Grenville Orogen And Keweenaw-Kapuskasing Inverted Foreland, Usa And Canada, John P. Craddock, Suzanne D. Craddock, Alex Konstantinou, Andrew R.C. Kylander-Clark, David H. Malone 2017 Illinois State University

Calcite Twinning Strain Variations Across The Proterozoic Grenville Orogen And Keweenaw-Kapuskasing Inverted Foreland, Usa And Canada, John P. Craddock, Suzanne D. Craddock, Alex Konstantinou, Andrew R.C. Kylander-Clark, David H. Malone

Faculty Publications - Geography, Geology, and the Environment

We report the calcite twinning strain results of a traverse across the Grenville orogen from Parry Sound, Ontario (NW) to Ft. Ann, New York (SE), including the younger, adjacent Ordovician Taconic allochthon. Fifty four carbonates (marbles, calcite veins, Ordovician limestone) were collected resulting in 68 strain analyses on mechanically twinned calcite (n ¼ 2337 grains) across the Central Gneiss Belt (CGB; 3 samples), the Central Metasedimentary Belt (CMB; 27 samples), the Central Granulite Terrane (CGT; Adirondack’s; 13 samples) and the Ottawan Orogenic Lid (OOL; 11 samples). Twinning strains in the greenschist-grade OOL marbles preserve NeS shortening and U-Pb titanite ages …


Mechanical Models Favor A Ramp Geometry For The Ventura-Pitas Point Fault, California, Scott T. Marshall, Gareth J. Funning, Hannah E. Kreuger, Susan E. Owen, John P. Loveless 2017 Appalachian State University

Mechanical Models Favor A Ramp Geometry For The Ventura-Pitas Point Fault, California, Scott T. Marshall, Gareth J. Funning, Hannah E. Kreuger, Susan E. Owen, John P. Loveless

Geosciences: Faculty Publications

Recent investigations have provided new and significantly revised constraints on the subsurface structure of the Ventura-Pitas Point fault system in southern California; however, few data directly constrain fault surfaces below ~6 km depth. Here, we use geometrically complex three-dimensional mechanical models driven by current geodetic strain rates to test two proposed subsurface models of the fault system. We find that the model that incorporates a ramp geometry for the Ventura-Pitas Point fault better reproduces both the regional long term geologic slip rate data and interseismic GPS observations of uplift in the Santa Ynez Mountains. The model-calculated average reverse slip rate …


Holocene History Of Deep-Seated Landsliding In The North Fork Stillaguamish River Valley From Surface Roughness Analysis, Radiocarbon Dating, And Numerical Landscape Evolution Modeling, Adam M. Booth, Sean R. LaHusen, Alison R. Duvall, David R. Montgomery 2017 Portland State University

Holocene History Of Deep-Seated Landsliding In The North Fork Stillaguamish River Valley From Surface Roughness Analysis, Radiocarbon Dating, And Numerical Landscape Evolution Modeling, Adam M. Booth, Sean R. Lahusen, Alison R. Duvall, David R. Montgomery

Geology Faculty Publications and Presentations

Documenting spatial and temporal patterns of past landsliding is a challenging step in quantifying the effect of landslides on landscape evolution. While landslide inventories can map spatial distributions, lack of dateable material, landslide reactivations, or time, access, and cost constraints generally limit dating large numbers of landslides to analyze temporal patterns. Here we quantify the record of the Holocene history of deep-seated landsliding along a 25 km stretch of the North Fork Stillaguamish River valley, Washington State, USA, including the 2014 Oso landslide, which killed 43 people. We estimate the ages of more than 200 deep-seated landslides in glacial sediment …


Investigation Of Firn Aquifer Structure In Southeastern Greenland Using Active Source Seismology, Lynn N. Montgomery, Nicholas Schmerr, Scott Burdick, Richard R. Forster, Lora Koenig, Anatoly Legchenko, Stefan Ligtenberg, Clément Miège, Olivia L. Miller, D. Kip Solomon 2017 Department of Geology, University of Maryland, College Park, MD

Investigation Of Firn Aquifer Structure In Southeastern Greenland Using Active Source Seismology, Lynn N. Montgomery, Nicholas Schmerr, Scott Burdick, Richard R. Forster, Lora Koenig, Anatoly Legchenko, Stefan Ligtenberg, Clément Miège, Olivia L. Miller, D. Kip Solomon

Environmental Science and Geology Faculty Research Publications

In spring of 2011, a perennial storage of water was observed in the firn of the southeastern Greenland Ice Sheet (GrIS), a region of both high snow accumulation and high melt. This aquifer is created through percolation of surface meltwater downward through the firn, saturating the pore space above the ice-firn transition. The aquifer may play a significant role in sea level rise through storage or draining freshwater into the ocean. We carried out a series of active source seismic experiments using continuously refracted P-waves and inverted the first P-arrivals using a transdimensional Bayesian approach where the depth, velocity, and …


Murray Energy Corporation V. Mccarthy, Sarah M. Danno 2017 University of Montana School of Law

Murray Energy Corporation V. Mccarthy, Sarah M. Danno

Public Land & Resources Law Review

Holding that the widespread effects of environmental regulation on the coal industry constituted sufficient importance, the Northern District of West Virginia ordered the Environmental Protection Agency to conduct analysis on employment loss and plant reduction resulting from regulatory effects. In admonishing the EPA’s inaction, the court ruled that the Agency had a non-discretionary duty to evaluate employment and plant reduction. Furthermore, the court held that the EPA’s attempt to put forth general reports in place of required evaluations was an invalid attempt to circumvent its statutory duty.


Super-Interseismic Periods: Redefining Earthquake Recurrence, John P. Loveless 2017 Smith College

Super-Interseismic Periods: Redefining Earthquake Recurrence, John P. Loveless

Geosciences: Faculty Publications

Precise geodetic measurements made over broad swaths of tectonically active regions record patterns of interseismic strain accumulation, providing key insights into the locus and timing of pending earthquakes. Recent studies of geodetic position time series, including that of Melnick et al. (2017), illustrate temporal variation in the pattern of interseismic deformation. These authors propose that the 2010 Mw = 8.8 Maule, Chile, earthquake enhanced coupling on the Andean subduction zone adjacent to the rupture, including on the portion of the megathrust that broke 5 years later in the Mw = 8.3 Illapel event.


So, You Want To 3d Print A Landscape? An Outline Of Some Methods, Dylan J. McKevitt, Thomas L. Rice, Emily Jackson, Victoria Couser 2017 Cedarville University

So, You Want To 3d Print A Landscape? An Outline Of Some Methods, Dylan J. Mckevitt, Thomas L. Rice, Emily Jackson, Victoria Couser

Alumni Book Gallery

No abstract provided.


The Tuscaloosa Marine Shale: Geologic History, Depositional Analysis, And Exploration Potential, Jessica D. Pair 2017 Stephen F Austin State University

The Tuscaloosa Marine Shale: Geologic History, Depositional Analysis, And Exploration Potential, Jessica D. Pair

Electronic Theses and Dissertations

The Tuscaloosa Marine Shale (TMS) was deposited across southern Louisiana and Mississippi during the Upper Cretaceous. The study focuses on a core region containing vast deposits of Cretaceous-aged sediments that have economic importance for oil and gas exploration. This region has been conventionally drilled for decades, focusing on the recovery of the Cretaceous hydrocarbons. Explorers within this region had traditionally targeted the massive sand units of the Lower and Upper Tuscaloosa Group while neglecting the middle Tuscaloosa Marine Shale unit. With the onset of unconventional drilling technology, new explorers to the region have begun to delineate the Tuscaloosa Marine Shale’s …


Facies Analysis, Sedimentary Petrology, And Reservoir Characterization Of The Lower Triassic Sinbad Limestone Member Of The Moenkopi Formation, Central Utah: A Synthesis Of Surface And Subsurface Data, Kristopher Michael Powell 2017 Brigham Young University

Facies Analysis, Sedimentary Petrology, And Reservoir Characterization Of The Lower Triassic Sinbad Limestone Member Of The Moenkopi Formation, Central Utah: A Synthesis Of Surface And Subsurface Data, Kristopher Michael Powell

Theses and Dissertations

Lower Triassic strata in the Wellington Flat and Tully cores reflect a lateral transition from shallow water strata (Wellington Flats core) to strata that indicate deposition on a relatively more distal, storm-dominated ramp (Tully core). The Sinbad Member, along with the upper part of the underlying Black Dragon Member and the lower part of the overlying Torrey Member (Moenkopi Formation), are composed of ten carbonate, siliciclastic and mixed carbonate/siliciclastic facies deposited on a west-facing ramp/shelf that reached maximum flooding during Smithian time. Individual beds and facies display a large degree of lateral homogeneity and regional persistence in the study area. …


Basic Meteorological Data Derived 30-Year Normas (1981-2010) Of Actual Evapotranspiration Rates In Nebraska, Usa, Jozsef Szilagyi 2017 University of Nebraska-Lincoln

Basic Meteorological Data Derived 30-Year Normas (1981-2010) Of Actual Evapotranspiration Rates In Nebraska, Usa, Jozsef Szilagyi

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


Secondary Minerals From Salt Caves In The Atacama Desert (Chile): A Hyperarid And Hypersaline Environment With Potential Analogies To The Martian Subsurface, Jo De Waele, Cristina Carbone, Laura Sanna, Marco Vattano, Ermanno Galli, Francesco Sauro, Paolo Forti 2017 University of Bologna

Secondary Minerals From Salt Caves In The Atacama Desert (Chile): A Hyperarid And Hypersaline Environment With Potential Analogies To The Martian Subsurface, Jo De Waele, Cristina Carbone, Laura Sanna, Marco Vattano, Ermanno Galli, Francesco Sauro, Paolo Forti

International Journal of Speleology

Over the past 15 years several expeditions by French, American and especially Italian cavers have unveiled over 50 caves in the Cordillera de la Sal (Atacama Desert, Northern Chile). Many of these caves contain a variety of speleothems and minerals, some of which have rarely been observed within karst systems. Most of the secondary deposits in these caves are composed of halite, but also other halide, carbonate, sulphate, nitrate, phosphate, and silicate minerals have been found. Among the sixteen cave mineral species recognized, atacamite, darapskite, blödite, leonite, anhydrite, and especially antarcticite are worth mentioning. In one of the samples an …


Memorium: Bhamidipati Lakshmidhara Kanakadri Somayajulu (1937-2016), Mark Baskaran, R. Ramesh 2017 Department of Geology, Wayne State University, Detroit, MI

Memorium: Bhamidipati Lakshmidhara Kanakadri Somayajulu (1937-2016), Mark Baskaran, R. Ramesh

Environmental Science and Geology Faculty Research Publications

The demise of B. L. K. Somayajulu, an illustrious nuclear geochemist, brings great sadness to the community of geo- logists, geochemists and oceanographers in India and elsewhere.


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