Depositional Environment And Facies Analyses Of The Owl Mountain Province, Fort Hood Military Installation, Bell And Coryell Counties, Texas,
2018
Stephen F. Austin State University
Depositional Environment And Facies Analyses Of The Owl Mountain Province, Fort Hood Military Installation, Bell And Coryell Counties, Texas, Jacob Meinerts
Electronic Theses and Dissertations
The Owl Mountain Province is a plateaued, karst landscape located in the eastern section of the Fort Hood Military Installation and is characterized by Lower Cretaceous Fredericksburg Group carbonates. The topography is capped by thick sequences of the Edwards limestone; steep scarps and incised valleys along the edges of the plateaus host inter-fingering outcrops of the Edwards and Comanche Peak limestones, and the lower valleys are covered by alluvial sediments and intermittent outcrops of the Walnut Clay. These formations were deposited to the north and west of the main Edwards trend, and are thought to be part of a series …
Speleogenesis In Turbulent Flow,
2018
University of Arkansas, Fayetteville
Speleogenesis In Turbulent Flow, Max P. Cooper
Graduate Theses and Dissertations
Existing models of speleogenesis neglect the shape of cross-sections, which can hold information related to climate, tectonics, and sediment supply in their widths. The first study of this dissertation simulates cross-sections of phreatic tubes, vadose canyons, and paragenetic galleries using a method developed for bedrock channels. Successful simulation of these cross-sections depends on erosion scaling with shear stress, in conflict with speleogenesis theory. Scaling of equilibrium width in paragenetic galleries was explored through analytical derivation and simulations, showing that width scales positively with discharge to the 1/2 power, and negatively with a weak power of sediment supply. Negative scaling of …
Keeping Pace With Relative Sea Level Rise: Marsh Platform Monitoring Shows Minimal Sediment Deficit Along The Louisiana Coast,
2018
University of Arkansas, Fayetteville
Keeping Pace With Relative Sea Level Rise: Marsh Platform Monitoring Shows Minimal Sediment Deficit Along The Louisiana Coast, Kelly Marie Sanks
Graduate Theses and Dissertations
Recent reports estimate that the marshes of the Mississippi Delta receive just 30% of the sediment necessary to sustain current land area1. An extensive monitoring campaign by the USGS and LCPRA provides direct measurements of sediment accumulation, subsidence rates, and deposit characteristics along the coast over the past 10 years2, allowing us to directly evaluate this sediment balance. By interpolating bulk density, organic fraction, and vertical accretion rates from 273 sites, a direct measurement of organic and inorganic sediment accumulation can be made. Results show that a total of 82 MT/year of sediment is delivered to the coast. Using a …
The Role Of Mites In The Construction And Weathering Of Siliceous Biospeleothems,
2018
University of Coruña
The Role Of Mites In The Construction And Weathering Of Siliceous Biospeleothems, María José López-Galindo
International Journal of Speleology
Acarines are well-documented as formative elements in the biocenosis of soils. However, their role in the construction and weathering of siliceous speleothems has received very little attention in previous research. The present study describes different groups of cavities (nesting/molting sites) excavated by these organisms in the surface of siliceous speleothems that are deposited in the fissures between various granite boulders in Southern Spain. There is evidence that there are immature stages that would survive the heat and drought of summer in the form of small larvae, or euedaphic nymphs, in the soil. This study provides the first description of how …
Remains Of The 19th Century: Deep Storage Of Contaminated Hydraulic Mining Sediment Along The Lower Yuba River, California,
2018
San Jose State University
Remains Of The 19th Century: Deep Storage Of Contaminated Hydraulic Mining Sediment Along The Lower Yuba River, California, Tyler Nakamura, Michael Bliss Singer, Emmanuel Gabet
Faculty Publications
Since the onset of hydraulic gold mining in California’s Sierra Nevada foothills in 1852, the environmental damage caused by displacement and storage of hydraulic mining sediment (HMS) has been a significant ecological problem downstream. Large volumes of mercury-laden HMS from the Yuba River watershed were deposited within the river corridor, creating the anthropogenic Yuba Fan. However, there are outstanding uncertainties about how much HMS is still contained within this fan. To quantify the deep storage of HMS in the Yuba Fan, we analyzed mercury concentrations of sediment samples collected from borings and outcrops at multiple depths. The mercury concentrations served …
Interpreting The Origin And Evolution Of ‘Karst’ Features From A Siliceous Hydrothermal Terrane: A Case Study From The Upper Geyser Basin In Yellowstone National Park, Usa,
2018
East Central University
Interpreting The Origin And Evolution Of ‘Karst’ Features From A Siliceous Hydrothermal Terrane: A Case Study From The Upper Geyser Basin In Yellowstone National Park, Usa, Kevin W. Blackwood, Lainee A. Sanders, Stacy I. Gantt-Blackwood
International Journal of Speleology
The Upper Geyser Basin in Yellowstone National Park occurs over a siliceous hydrothermal terrane containing numerous hot springs and geysers. The pool and vent-conduit geometries of these hydrothermal features share a resemblance to conventional karst features known from other rock types, suggesting karst processes could be responsible for their origin and/or evolution. Hypogene speleogenesis is a cave-forming process in which the formation of caves is decoupled from and occurs independently of surface recharge. The geologic setting for hypogene speleogenesis typically occurs at the distal end of regional groundwater systems wherein the hydrogeology is manifested by ascending fluids and/or by geochemical …
An Overview Of Smartwater Management System: Strategic Potential In Bangladesh,
2018
University of Dhaka
An Overview Of Smartwater Management System: Strategic Potential In Bangladesh, Muhammad Qumrul Hassan, Mir F. Karim, Nazrul I. Khandaker, Jowaher Raza
Publications and Research
Water loss management is becoming an increasingly important as supplies are stressed by population growth or water scarcity. A SmartWater system ensures optimum consumption and prediction of future water use. Bangladesh is one of the most vulnerable countries due to global climate change considering its rapid urbanization, inequitable land use, low income and greater reliance on climate sensitive sectors, particularly agriculture. Agricultural lands used for cropping and livestock rearing are more susceptible to degradation than non-agricultural lands. Most farmers irrigate through flooding, losing up to 75% of water to evaporation and creating a substantial drawdown of much needed water for …
The Status Of Engineering Geology: Constraints On Infrastructure Development In Bangladesh,
2018
Geotesting Express Inc.
The Status Of Engineering Geology: Constraints On Infrastructure Development In Bangladesh, Mir Fazlul Karim, Muhammad Qumrul Hassan, Nazrul I. Khandaker, Masud Ahmed, Belal Ahmed Sayeed
Publications and Research
In recent years, megacity Dhaka is known to have one of the fastest urban population growths in Bangladesh. The population in Dhaka and other megacities has increased from 7 to 50 million during the last four decades. The rapid rate of urban population growth, along with the extreme paucity of real-estate for new infrastructure development or upgrading existing facilities, is already exacerbating the situation for the city planners and exerting tremendous pressure to come-up with viable solutions. Although practice of engineering geology, geotechnical exploration, and testing exists in Bangladesh; the system has still yet to adopt controlled quality standards with …
The Challenges Of Geotechnical Exploration In Bangladesh For Sustainable Urban Development And Risk Reductions In Engineering Geology,
2018
Geotesting Express Inc.
The Challenges Of Geotechnical Exploration In Bangladesh For Sustainable Urban Development And Risk Reductions In Engineering Geology, Mir Fazul Karim, Nazrul I. Khandaker, Muhammad Qumrul Hasson, A.T.M. Shakhawat Hossain
Publications and Research
Bangladesh is a unique example of rapid urbanization where the urban population increased from 5 to 58 million in last four decades. Due to complex geology and active tectonic setting, the urban ground is impacted by fluvio-deltaic processes and regional seismicity. The densely populated cities of the country are facing risks from many natural hazards like floods, tidal surge, riverbank and coastal erosion, scour, landslides, soil collapse and foundation failures. Geologists anticipate severe seismic threats from yet-undefined tectonic structures and seek to determine their consequential geo-structural responses and conformance to the national building code. With rapid growth, demands on infrastructure …
An Evaluation Of Modified Bed Load Sediment Transport Equations For Enhanced Sediment Transport Quantification In Steep Mountain Streams – Case Study Little Fountain Creek, Colorado Springs, Co.,
2018
Louisiana State University and Agricultural and Mechanical College
An Evaluation Of Modified Bed Load Sediment Transport Equations For Enhanced Sediment Transport Quantification In Steep Mountain Streams – Case Study Little Fountain Creek, Colorado Springs, Co., James Emerson Smith Iv
LSU Master's Theses
In mountainous regions, extreme floods occur every year, placing societies and infrastructures at risk. Communities rely on local, state, and federal agencies to emplace flood structures, perform flood risk assessments, and simulate catastrophic events. While, our ability to quantify and predict the movement of sediment in streams with low gradients is well developed (Bathurst, 1987), our ability to quantify and predict the movement of sediment along steep mountain streams (SMS) has not been developed to a similar degree (Yager, 2012; Schneider, 2016). To most effectively manage mountainous watersheds and understand the risk associated with flood events, scientists must better understand …
Analysis Of Fluvial Scroll Bar Development With Surface Wave Inversion: False River, Louisiana,
2018
Louisiana State University and Agricultural and Mechanical College
Analysis Of Fluvial Scroll Bar Development With Surface Wave Inversion: False River, Louisiana, Blake Odom
LSU Master's Theses
The development of ridge-and-swale scroll bar topography of meandering river point bars is not well understood. We hypothesize that scroll bars formed during lateral accretion by the landward migration of transverse bars. To explore this, we relate the scroll bar topography to the internal sedimentary structure. We acquire, invert, and interpolate three pseudo-2D shear wave velocity profiles in two regions of the False River point bar, a Mississippi river oxbow lake in Pointe Coupee Parish Louisiana. Prior studies provide electrical conductivity well logs and cores as well as SH seismic reflection images along the same seismic surveys. LiDAR elevation data …
Crustal Seismic Anisotropy Of The Ruby Mountains Core Complex And Surrounding Northern Basin And Range,
2018
University of New Mexico
Crustal Seismic Anisotropy Of The Ruby Mountains Core Complex And Surrounding Northern Basin And Range, Justin T. Wilgus
Earth and Planetary Sciences ETDs
Metamorphic core complexes (MCC) are distinctive uplifts that expose deeply exhumed and deformed crustal rocks due to localized extensional deformation. Consequently, their detailed structure provide a window into deep crustal mechanics. The North American Cordillera contains numerous MCC, one of which is the Ruby Mountains core complex (RMCC) located in the highly extended northern Basin and Range. To constrain the extent to which anisotropy below the RMCC deviates from the regional Basin and Range average and test the depth dependence of crustal anisotropy we conduct a radial anisotropy investigation below the RMCC and surrounding northern Basin and Range. Data from …
The Cyrilka Cave—The Longest Crevice-Type Cave In Czechia: Structural Controls, Genesis, And Age,
2018
University of Ostrava
The Cyrilka Cave—The Longest Crevice-Type Cave In Czechia: Structural Controls, Genesis, And Age, Jan Lenart, Martin Kašing, Petr Tábořík, Natalia Piotrowska, Jacek Pawlyta
International Journal of Speleology
The Cyrilka Cave is the second longest pseudokarst cave and the longest crevice-type cave in Czechia. Developed within the headscarp area of a deep-seated landslide, the cave became a focus of scientific research in recent years when new passages were discovered. Structural analysis provided a general tectonic plan of the cave, as well as more detailed data on geometry and kinematics of the relaxed rock massif. The primary structure of NNE- to ENE-striking bedding is broken by a system of NNE-striking fissures interconnected by two continuous ENE-striking dextral fracture zones. Abundant signs of recent sinistral strike-slips within the rock massif …
Three-Dimensional Flow, Morphologic Change, And Sediment Deposition And Distribution Of Actively Evolving Neck Cutoffs Located On The White River, Arkansas,
2018
Louisiana State University and Agricultural and Mechanical College
Three-Dimensional Flow, Morphologic Change, And Sediment Deposition And Distribution Of Actively Evolving Neck Cutoffs Located On The White River, Arkansas, Derek Allen Richards
LSU Doctoral Dissertations
Neck cutoffs are important and prominent features of alluvial rivers yet detailed field-based research of neck cutoffs has been insufficient to fully characterize three-dimensional flow, morphologic change, and sediment deposition and distribution. The main objectives of this research are to examine the formation and evolution of neck cutoffs by characterizing the flow field, morphology, and sediment distribution through neck cutoffs with complex planform configurations located on the White River, Arkansas. Results led to the production of two conceptual models. The flow model has main hydrodynamic characteristics of (1) tight bend flow resulting from flow redirection of nearly 180° through the …
Rates Of Planimetric Change In A Proglacial Gravel-Bed Braided River: Field Measurement And Physical Modeling,
2018
U. Western Ontario
Rates Of Planimetric Change In A Proglacial Gravel-Bed Braided River: Field Measurement And Physical Modeling, Lara Middleton, Peter Ashmore, Pauline Leduc, Darren Sjogren
Geography & Environment Publications
Planimetric change was measured on daily hydrographs over two meltwater seasons using time-lapse images of the proglacial, gravel, braided, Sunwapta River, Canada. Significant planimetric change occurred on 10-15 days per year. Area of planimetric change correlated with peak and total daily meltwater hydrograph discharge. A clear threshold discharge can be identified below which no planform activity occurs, an intermediate range over which change occurs conditionally, and a peak flow range at which significant change always occurs. Field conditions were reproduced in a physical model in a laboratory flume. Photogrammetric DEMs of bed morphology and measurements of bedload output were made …
Geologic Mapping Of Nebraska: Old Rocks, New Maps, Fresh Insights,
2018
University of Nebraska-Lincoln
Geologic Mapping Of Nebraska: Old Rocks, New Maps, Fresh Insights, R. Matthew Joeckel, Robert F. Diffendal Jr., P. R. Hanson, Jesse T. Korus
Robert F. Diffendal, Jr., Publications
Geologic mapping in Nebraska and environs is an ongoing endeavor that has spanned more than 170 years, involved dozens of scientists, and evolved through many changes. Digital mapping has risen to dominance in the state only since 1996. Geologic mapping in Nebraska today concentrates on surficial mapping, which emphasizes materials exposed at the land surface and their relationships with landforms, and which is particularly relevant because non- bedrock geologic materials (regolith) lie at the surface across at least 87% of the state. Moreover, surfi cial geologic maps assist the understanding of groundwater and sand and gravel resources, to name a …
Unroofing History Of The Northwestern Ethiopian Plateau: Insights From Low-Temperature Apatite Thermochronology,
2018
Western Kentucky University
Unroofing History Of The Northwestern Ethiopian Plateau: Insights From Low-Temperature Apatite Thermochronology, Shelby Bowden
Masters Theses & Specialist Projects
The geology of Ethiopia is dominated by the Ethiopian Plateau that is similar in elevation to, but aerially larger than, the Colorado Plateau. Several rivers have incised through the plateau, creating gorges that reach up to 1.5 km in depth. The plateau uplifted to its current elevation and was subsequently incised sometime after the Oligocene flood basalt event that signaled the arrival of the African Superplume below Kenya and Ethiopia. Due to its size and extent, published climate modeling has indicated that Late Cenozoic plateau formation could have been a driving force in the East African Cenozoic climate changes. Although …
Controls On Speleogenesis In The Upper-Mississippian Pennington Formation On The Western Cumberland Plateau Escarpment,
2018
Western Kentucky University
Controls On Speleogenesis In The Upper-Mississippian Pennington Formation On The Western Cumberland Plateau Escarpment, Hali Steinmann
Masters Theses & Specialist Projects
Much of the pioneering work on caves of the Cumberland Plateau (province spanning Tennessee, Kentucky, Alabama, and Georgia) has been stratigraphically located within the Mississippian Bangor and Monteagle Limestones, wherein some of the region’s largest and most spectacular caves occur. Of interest to the understanding of this karst landscape, but severely underrepresented in the literature thereof, are caves and karst features in a heterogeneous sequence of clastics and carbonates known collectively as the Pennington Formation (Upper Mississippian). This work consisted of a regional study of Pennington caves on the western Cumberland Plateau escarpment (Alabama and Tennessee), and a case study …
New Insights Into Carboniferous Cyclothems. The Fourth Biennial Field Conference Of The American Association Of Petroleum Geologists (Aapg) Midcontinent Section Fourth Biennial Field Conference Abstracts And Guidebook,
2018
University of Nebraska - Lincoln
New Insights Into Carboniferous Cyclothems. The Fourth Biennial Field Conference Of The American Association Of Petroleum Geologists (Aapg) Midcontinent Section Fourth Biennial Field Conference Abstracts And Guidebook, Robert Matthew Joeckel, Christopher R. Fielding
Conservation and Survey Division: Faculty and Staff Publications
The term “cyclothem” was coined by Wanless & Weller (1932) to describe repetitive stratigraphic successions of Carboniferous age in Illinois. Nonetheless, comparable rhythmicity had been identified in Carboniferous rocks both in the central and eastern USA, and in Europe during the preceding century. Cyclothems were found to comprise repetitive vertical successions of sandstones, heterolithic (thinly interbedded) sandstones and mudrocks, mudrocks, limestones, and coals, in many cases with pedogenic overprinting of these lithologies. As usage of the term “cyclothem” increased, so did the diversity of successions to which the term was applied, to the point where many geologists advocated abandonment of …
Evolution Of Grain Size Distributions And Bed Mobility During Hydrographs In Gravel-Bed Braided Rivers,
2018
Western University
Evolution Of Grain Size Distributions And Bed Mobility During Hydrographs In Gravel-Bed Braided Rivers, Sarah Peirce, Peter Ashmore, Pauline Leduc
Geography & Environment Publications
Evolution of bed material mobility and bedload grain size distributions under a range of discharges is rarely observed in braiding in gravel-bed rivers. Yet, the changing of bedload grain size distributions with discharge is expected to be different from laterally stable, threshold, channels on which most gravel bedload theory and observation are based. Here, simultaneous observations of flow, bedload transport rate, and morphological change were made in a physical model of a gravel-bed braided river to document the evolution of grain size distributions and bed mobility over three experimental event hydrographs. Bedload transport rate and grain size distributions were measured …
