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Origins Of Late- Pleistocene Coastal Dune Sheets, Magdalena And Guerrero Negro, From Continental Shelf Low-Stand Supply (70-20 Ka), Under Conditions Of Southeast Littoral- And Eolian-Sand Transport, In Baja California Sur, Mexico, Curt D. Peterson, Janette Murillo-Jiminez, Errol Stock, David M. Price, Steve W. Hostetler, David Percy 2017 Portland State University

Origins Of Late- Pleistocene Coastal Dune Sheets, Magdalena And Guerrero Negro, From Continental Shelf Low-Stand Supply (70-20 Ka), Under Conditions Of Southeast Littoral- And Eolian-Sand Transport, In Baja California Sur, Mexico, Curt D. Peterson, Janette Murillo-Jiminez, Errol Stock, David M. Price, Steve W. Hostetler, David Percy

Geology Faculty Publications and Presentations

Shallow morpho-stratigraphic sections (n = 11) in each of two large coastal dune sheets including the Magdalena (7000 km2) and Guerrero Negro (8000 km2) dune sheets, from the Pacific Ocean side of Baja California Sur, Mexico, have been analyzed for dune deposit age. The shallow morpho-stratigraphic sections (∼2-10 m depth) include 11 new TL and 14C ages, and paleosol chronosequences, that differentiate cemented late Pleistocene dune deposits (20.7 ± 2.1 to 99.8 ± 9.4 ka) from uncemented Holocene dune deposits (0.7 ± 0.05 to at least 3.2 ± 0.3 ka). Large linear dune ridges (5-10 ...


An Overview Of Secondary Aquifers In Nebraska, Dana Divine, Steven S. Sibray 2017 University of Nebraska-Lincoln

An Overview Of Secondary Aquifers In Nebraska, Dana Divine, Steven S. Sibray

Conservation and Survey Division

No abstract provided.


Mantle Transition Zone Discontinuities Beneath The Indochina Peninsula: Implications For Slab Subduction And Mantle Upwelling, Youqiang Yu, Stephen S. Gao, Kelly H. Liu, Ting Yang, Mei Xue, Khanhphon Le 2017 Missouri University of Science and Technology

Mantle Transition Zone Discontinuities Beneath The Indochina Peninsula: Implications For Slab Subduction And Mantle Upwelling, Youqiang Yu, Stephen S. Gao, Kelly H. Liu, Ting Yang, Mei Xue, Khanhphon Le

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

While the northward indentation of the Indian into Eurasian plates has been intensively investigated, its oblique subduction beneath the Indochina Peninsula (ICP) and the role it played on mantle structure and dynamics remain enigmatic. In this first regional-scale receiver function study of the mantle transition zone (MTZ) discontinuities beneath the ICP and its surrounding areas, we stack ~12,000 receiver functions recorded at 33 stations using a non-plane wave common-conversion-point stacking technique. Systematic spatial variations of MTZ thickness with departures between -21 and +24 km from the globally averaged value are revealed, providing independent evidence for the presence of slab ...


Seismic Anisotropy And Mantle Dynamics Beneath The Malawi Rift Zone, East Africa, Cory A. Reed, Kelly H. Liu, Youqiang Yu, Stephen S. Gao 2017 Missouri University of Science and Technology

Seismic Anisotropy And Mantle Dynamics Beneath The Malawi Rift Zone, East Africa, Cory A. Reed, Kelly H. Liu, Youqiang Yu, Stephen S. Gao

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

SKS, SKKS, and PKS splitting parameters measured at 34 seismic stations that we deployed in the vicinity of the Cenozoic Malawi Rift Zone (MRZ) of the East African Rift System demonstrate systematic spatial variations with an average splitting time of 1.0 ± 0.3 s. The overall NE-SW fast orientations are consistent with absolute plate motion (APM) models of the African Plate constructed under the assumption of no-net rotation of the global lithosphere and are inconsistent with predicted APM directions from models employing a fixed hot spot reference frame. They also depart considerably from the trend of most of the ...


Analysis Of The Hite Fault Group, Southeast Utah: Insights Into Fluid Flow Properties In A Reservoir Analog, Daniel J. Curtis 2017 Utah State University

Analysis Of The Hite Fault Group, Southeast Utah: Insights Into Fluid Flow Properties In A Reservoir Analog, Daniel J. Curtis

All Graduate Theses and Dissertations

In the subsurface faults can act as both barriers and conduits for fluids or gases such as CO2, hydrocarbons, or water. It is often thought that faults in porous rocks such as sandstone are barriers to fluid flow. In this study we show that this is not always the case. In sandstones like the Cedar Mesa Sandstone it is very important to understand the relationships between this history of fault slip and fluid flow. Better understanding of how fluids migrate through faults and the damaged areas surrounding these faults has strong significance to the oil and gas industry.

In ...


Analyzing Glacier Surface Motion Using Lidar Data, Jennifer W. Tellig, Craig Glennie, Andrew G. Fountain, David C. Finnegan 2017 University of Houston

Analyzing Glacier Surface Motion Using Lidar Data, Jennifer W. Tellig, Craig Glennie, Andrew G. Fountain, David C. Finnegan

Andrew G. Fountain

Understanding glacier motion is key to understanding how glaciers are growing, shrinking, and responding to changing environmental conditions. In situ observations are often difficult to collect and offer an analysis of glacier surface motion only at a few discrete points. Using light detection and ranging (LiDAR) data collected from surveys over six glaciers in Greenland and Antarctica, particle image velocimetry (PIV) was applied to temporally-spaced point clouds to detect and measure surface motion. The type and distribution of surface features, surface roughness, and spatial and temporal resolution of the data were all found to be important factors, which limited the ...


Slope, Grain Size, And Roughness Controls On Dry Sediment Transport And Storage On Steep Hillslopes, Roman A. DiBiase, Michael P. Lamb, Vamsi Ganti, Adam M. Booth 2017 Pennsylvania State University

Slope, Grain Size, And Roughness Controls On Dry Sediment Transport And Storage On Steep Hillslopes, Roman A. Dibiase, Michael P. Lamb, Vamsi Ganti, Adam M. Booth

Adam M. Booth

Existing hillslope sediment transport models developed for low-relief, soil-mantled landscapes are poorly suited to explain the coupling between steep rocky hillslopes and headwater channels. Here we address this knowledge gap using a series of field and numerical experiments to inform a particle-based model of sediment transport by dry ravel—a mechanism of granular transport characteristic of steep hillslopes. We find that particle travel distance increases as a function of the ratio of particle diameter to fine-scale (1m) topographic variability associated with rocky landscapes. Applying a 2-D dry-ravel-routing model to lidar-derived surface topography, we show how spatial patterns of local and ...


Investigating The Effects Of Land-Cover Change On The Hydrologic Conditions Of A Restored Agricultural Area In Everglades National Park, Dillon Reio 2017 Florida International University

Investigating The Effects Of Land-Cover Change On The Hydrologic Conditions Of A Restored Agricultural Area In Everglades National Park, Dillon Reio

FIU Electronic Theses and Dissertations

In the Florida Everglades, remodeling of natural wetlands to promote agriculture and human settlement, have profoundly altered its hydrologic regime. As a result of anthropogenic changes, many restoration programs have been initiated to restore hydrologically controlled wetland ecosystems. One such restoration project that has been ongoing for the past 27 years is the Hole-in-the-Donut restoration program in Everglades National Park. The restoration program is unique in that it utilized an unorthodox technique to restore the landscape. The viability of the restoration technique was assessed by coupling long-term hydrologic and evapotranspiration data with water chemistry analyses. Key results indicated that the ...


Using The Storm Water Management Model To Predict Urban Headwater Stream Hydrological Response To Climate And Land Cover Change, J. Y. Wu, Janette R. Thompson, R. K. Kolka, Kristie J. Franz, Timothy W. Stewart 2017 Iowa State University

Using The Storm Water Management Model To Predict Urban Headwater Stream Hydrological Response To Climate And Land Cover Change, J. Y. Wu, Janette R. Thompson, R. K. Kolka, Kristie J. Franz, Timothy W. Stewart

Timothy W. Stewart

Streams are natural features in urban landscapes that can provide ecosystem services for urban residents. However, urban streams are under increasing pressure caused by multiple anthropogenic impacts, including increases in human population and associated impervious surface area, and accelerated climate change. The ability to anticipate these changes and better understand their effects on streams is important for developing and implementing strategies to mitigate potentially negative effects. In this study, stream flow was monitored during April-November (2011 and 2012), and the data were used to apply the Storm Water Management Model (SWMM) for five urban watersheds in central Iowa, USA, representing ...


Mineral Evidence For Generating Compositionally Zoned Rhyolites Of The Devine Canyon Tuff, High Lava Plains, Oregon, Erik Paul Shafer 2017 Portland State University

Mineral Evidence For Generating Compositionally Zoned Rhyolites Of The Devine Canyon Tuff, High Lava Plains, Oregon, Erik Paul Shafer

Dissertations and Theses

Large-volume silicic eruptions are often evacuated from magma reservoirs which display gradients in composition, temperature, crystallinity, and volatile content. The 9.7 Ma Devine Canyon Tuff (DCT) of eastern Oregon represents such an eruption, with >300 km3 of compositionally zoned pyroclastic material deposited as a variably-welded ignimbrite. The ignimbrite displays homogenous bulk tuff major element compositions with a wide range of trace element compositions, allowing for the investigation of how these magmas were generated, stored, and modified in the magma reservoir by studying pumices which represent the primary magmas composing the DCT. Five pumices ranging from dacite to rhyolite bulk ...


Rhyolite Petrogenesis At Tower Mountain Caldera, Or, Elizabeth Ann Brown 2017 Portland State University

Rhyolite Petrogenesis At Tower Mountain Caldera, Or, Elizabeth Ann Brown

Dissertations and Theses

Tower Mountain Caldera is the main feature of an Oligocene volcanic field located in the Umatilla National Forest, eastern Oregon. It is perfectly suited to investigate models of rhyolite petrogenesis as all of the important rock components for evaluating generation models are present in a single location and thus are presumably related; basalts, intermediate igneous rocks (which consist of older plutons and younger volcanic rocks, which are ~coeval with rhyolites), metamorphic basement rocks of significant grade, and rhyolites of varying composition. The formation of the caldera produced the Dale Tuff, which comprises the intra-caldera and outflow facies. 40Ar/39 ...


Characterizing Benthic Habitats Using Multibeam Sonar And Towed Underwater Video In Two Marine Protected Areas On The West Florida Shelf, Usa, Jennifer L. Brizzolara 2017 University of South Florida

Characterizing Benthic Habitats Using Multibeam Sonar And Towed Underwater Video In Two Marine Protected Areas On The West Florida Shelf, Usa, Jennifer L. Brizzolara

Graduate Theses and Dissertations

This study investigates a way to characterize the geology and biology of the seafloor in two Marine Protected Areas on the West Florida Shelf. Characterization of benthic habitats needs to include sufficient detail to represent the complex and heterogeneous bottom types. Characterizations can be interpreted from multiple data sets and displayed as benthic habitat maps. Multibeam sonar bathymetry and backscatter provide full spatial data coverage, but interpretation of such data requires some form of ground truth (to characterize the habitat). Imagery from towed underwater video provides continuous transects of seafloor data, which provide a more efficient method than data from ...


Integrated Approach For Sinkhole Evaluation And Evolution Prediction In The Central Ebro Basin (Ne Spain), Oscar Pueyo Anchuela, Andrés Pocoví Juan, Antonio M. Casas Sainz, Javier Gracia Abadias, Carlos L. Liesa Carrera 2017 Universidad de Zaragoza

Integrated Approach For Sinkhole Evaluation And Evolution Prediction In The Central Ebro Basin (Ne Spain), Oscar Pueyo Anchuela, Andrés Pocoví Juan, Antonio M. Casas Sainz, Javier Gracia Abadias, Carlos L. Liesa Carrera

International Journal of Speleology

Evaluation of karst hazards benefits from the integration of different techniques, methodologies and approaches. Each one presents a different signature and is sensitive to certain indicators related to karst hazards. In some cases, detailed analysis permits the evaluation of representativeness either from isolated approaches or by means of integrated analyses. In this study, we present the evaluation of an area with high density of karstic collapses at different evolutionary stages through the integration of surficial, historical, geomorphological and geophysical data in order to finally define the evolutionary model for karst activity development. The obtained dataset permits to identify different steps ...


Karst Development Of An Evaporitic System And Its Hydrogeological Implications Inferred From Gis-Based Analysis And Tracing Techniques, José M. Gil-Márquez, Juan A. Barberá, Matías Mudarra, Bartolomé Andreo, Jorge Prieto-Mera, Damián Sánchez, L. David Rizo-Decelis, Manuel Argamasilla, José M. Nieto, Beatríz de la Torre 2017 University of Málaga

Karst Development Of An Evaporitic System And Its Hydrogeological Implications Inferred From Gis-Based Analysis And Tracing Techniques, José M. Gil-Márquez, Juan A. Barberá, Matías Mudarra, Bartolomé Andreo, Jorge Prieto-Mera, Damián Sánchez, L. David Rizo-Decelis, Manuel Argamasilla, José M. Nieto, Beatríz De La Torre

International Journal of Speleology

The geomorphological characteristics and hydrogeological functioning of a geologically heterogeneous evaporitic karst plateau in Southern Spain were studied. Land surface information (LiDAR data) was used to analyze the shape and distribution of closed depressions. An artificial tracer test and monitoring of the natural responses of the main spring have allowed to infer the karstic development of the studied system. Three dyes were injected in selected swallow holes to trace the main groundwater flowpaths and to estimate the dimension of the conduit network. Discharge, electrical conductivity and temperature were monitored in the groundwater that drains the evaporitic plateau during an individual ...


Hydrogeological Flow In Gypsum Karst Areas: Some Examples From Northern Italy And Main Circulation Models, Bartolomeo Vigna, Ilenia M. D'Angeli, Adriano Fiorucci, Jo De Waele 2017 Polytechnic University of Turin

Hydrogeological Flow In Gypsum Karst Areas: Some Examples From Northern Italy And Main Circulation Models, Bartolomeo Vigna, Ilenia M. D'Angeli, Adriano Fiorucci, Jo De Waele

International Journal of Speleology

A Messinian succession containing gypsum beds crops out in northern Italy, mainly in Piedmont and along the northern flank of the Apennine mountains in Emilia-Romagna. These gypsum bodies have been extensively quarried at the surface, in outcrops, and through underground quarries. In Emilia-Romagna these gypsum outcrops can be rather extensive, several km long and up to 1 km wide, while in Piedmont they are mostly covered by silty-marly deposits of Upper Messinian and Pliocene age and show only sparse and small outcrops. The underground quarrying of these evaporite bodies in Piedmont has allowed studying in detail their hydrogeology, and the ...


Sedimentology And Taphonomy Of The Abydosaurus Mcintoshi Quarry, (Naturita Formation, Early Cretaceous, Latest Albian), Dinosaur National Monument, Utah, Aaron Daniel Holmes 2017 Brigham Young University

Sedimentology And Taphonomy Of The Abydosaurus Mcintoshi Quarry, (Naturita Formation, Early Cretaceous, Latest Albian), Dinosaur National Monument, Utah, Aaron Daniel Holmes

All Theses and Dissertations

The holotypic locality of the brachiosaurid titanosauriform sauropod, Abydosaurus mcintoshi, is quarry DNM-16, located in Dinosaur National Monument. The bones are preserved near the base of a heterolithic, trough cross stratified to planar bedded sandstone channel complex. The trough cross to planar bedded sandstones mark times of variable flow with times of high flow velocity based on bones whose upper surfaces were eroded before final burial. The abundance of mud with the dominant medium to fine sand, and poorly confined sandstone channels indicate the bones were transported and buried in medial to distal intermittent flows of a distributive fluvial system ...


Interpretive Geologic Cross Sections Across Lower Platte North Natural Resources District, Nebraska (Ccs-20), Dana Divine 2017 University of Nebraska - Lincoln

Interpretive Geologic Cross Sections Across Lower Platte North Natural Resources District, Nebraska (Ccs-20), Dana Divine

Conservation and Survey Division

No abstract provided.


Formation Of Rapakivi Feldspars In The Deer Isle Granite Complex, Coastal Maine: In Situ Lead Isotope And Trace Element Analysis, William Desmond OBrien 2017 Brigham Young University

Formation Of Rapakivi Feldspars In The Deer Isle Granite Complex, Coastal Maine: In Situ Lead Isotope And Trace Element Analysis, William Desmond Obrien

All Theses and Dissertations

Rapakivi and alkali feldspar phenocrysts from the Deer Isle Granite Complex were investigated using in situ trace element and Pb isotope geochemistry to see if magma mixing or isothermal decompression was responsible for their formation. Pb isotope and trace element profiles, along with CL imagery of quartz phenocrysts, indicate compositional changes in the magma chamber occurred during rapakivi and alkali feldspar growth. Repeated episodes of magma mixing/replenishment by relatively isotopically primitive and LREE enriched magmas (along with hybridized variations with the host magma) created localized disequilibration. Alkali feldspar phenocrysts proximal to these zones of thermal perturbation were first resorbed ...


Receiver Function And Gravity Constraints On Crustal Structure And Vertical Movements Of The Upper Mississippi Embayment And Ozark Uplift, Lin Liu, Stephen S. Gao, Kelly H. Liu, Kevin Lee Mickus 2017 Missouri University of Science and Technology

Receiver Function And Gravity Constraints On Crustal Structure And Vertical Movements Of The Upper Mississippi Embayment And Ozark Uplift, Lin Liu, Stephen S. Gao, Kelly H. Liu, Kevin Lee Mickus

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The Upper Mississippi Embayment (UME), where the seismically active New Madrid Seismic Zone resides, experienced two phases of subsidence commencing in the Late Precambrian and Cretaceous, respectively. To provide new constraints on models proposed for the mechanisms responsible for the subsidence, we computed and stacked P-to-S receiver functions recorded by 49 USArray and other seismic stations located in the UME and the adjacent Ozark Uplift and modeled Bouguer gravity anomaly data. The inferred thickness, density, and Vp/Vs of the upper and lower crustal layers suggest that the UME is characterized by a mafic and high-density upper crustal ...


The Effect Of Watershed Runoff And Sediment Resuspension On Turbidity And Sediment Deposition In St. John, Us Virgin Islands: Implications For Watershed And Marine Development And Restoration In Bays With Coral Reefs, Stephen E. Campbell 2017 University of San Diego

The Effect Of Watershed Runoff And Sediment Resuspension On Turbidity And Sediment Deposition In St. John, Us Virgin Islands: Implications For Watershed And Marine Development And Restoration In Bays With Coral Reefs, Stephen E. Campbell

Theses

In the US Virgin Islands (USVI), land-based (terrigenous) sedimentation has been identified as a major cause of coral stress. Development, such as the building of unpaved roads in steep coastal watersheds, has increased sediment yields and marine terrigenous sedimentation by up to an order of magnitude above background levels. When activated during storm events, ephemeral streams transport sediment from the watershed to coastal waters. Once deposited on the seafloor, resuspension of benthic sediments can further increase turbidity and deposition. However, isolating the relative contributions of runoff and resuspension to turbidity and deposition using conventional sediment trap monitoring has been challenging ...


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