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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 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 …


Recruiting And Retaining K9–16 Students Through Field- And Laboratory - Based Geoscience Experiences, Nazrul I. Khandaker, Stanley Schleifer, Arif M. Sikder, Krishna Mahabir, Ality Aghedo, Charren Cabaroy, Mildred M. Selby, Gugu Ginindza, Leonardo Sanchez 2018 CUNY York College

Recruiting And Retaining K9–16 Students Through Field- And Laboratory - Based Geoscience Experiences, Nazrul I. Khandaker, Stanley Schleifer, Arif M. Sikder, Krishna Mahabir, Ality Aghedo, Charren Cabaroy, Mildred M. Selby, Gugu Ginindza, Leonardo Sanchez

Publications and Research

Since 2004, we have been directly involved with the GSA to provide access and opportunities for K9-16 students, particularly those interested in the broader aspects of geoscience-related topics, to present their field-and- laboratory based research outcomes at professional conferences and to learn from each other. So far, well-over 400 students from the U. S. and abroad have taken advantage of this opportunity and participated our topical sessions. It is quite gratifying to report that many of these students, as a result of their attendance at the GSA conference, felt a continuing need for exposure to high-level professional venues with effective …


Groundwater Contamination At Coal Ash Deposit Sites In Kentucky, Brandon Rose 2018 Murray State University

Groundwater Contamination At Coal Ash Deposit Sites In Kentucky, Brandon Rose

Scholars Week

No abstract provided.


Kentucky Flood And Flash Flood Comparison Of 1996 And 2017 Using Gis, Harrison Kelly 2018 Murray State University

Kentucky Flood And Flash Flood Comparison Of 1996 And 2017 Using Gis, Harrison Kelly

Scholars Week

No abstract provided.


Measuring And Modeling Evolution Of Cryoconite Holes In The Mcmurdo Dry Valleys, Antarctica, Felix Jacob Zamora 2018 Portland State University

Measuring And Modeling Evolution Of Cryoconite Holes In The Mcmurdo Dry Valleys, Antarctica, Felix Jacob Zamora

Dissertations and Theses

Cryoconite holes are vertical columns of meltwater within the shallow subsurface of glaciers. In the McMurdo Dry Valleys (MDV) of Antarctica cryoconite holes are a source of meltwater and harbor microbial communities in an otherwise arid environment with low biologic activity. The holes form as sediments on the ice surface, which are darker than the surrounding ice, are preferentially heated by solar radiation. The warm sediments melt the underlying ice and migrate downwards. An ice lid forms, isolating them from the below-freezing atmosphere enabling them to remain thawed. In this study, field observations, laboratory experiments, and numerical modeling are used …


A Deep Eastern Equatorial Pacific Thermocline During The Last Glacial Maximum, H. L. Ford, C. L. McChesney, J. E. Hertzberg, J. F. McManus 2018 Old Dominion University

A Deep Eastern Equatorial Pacific Thermocline During The Last Glacial Maximum, H. L. Ford, C. L. Mcchesney, J. E. Hertzberg, J. F. Mcmanus

OES Faculty Publications

The mean state and variability of the tropical Pacificis influenced by the depth of the thermocline. During the Last Glacial Maximum (~21,000 years ago), the zonal sea surface temperature gradient across the equatorial Pacific was reduced and productivity was generally lower than modern. To understand the thermocline depth’s role in determining the Last Glacial Maximum tropical mean state, we reconstruct the upper ocean δ18O profile from multiple species of planktic foraminifera. We synthesize existing records of surface and subsurface dwelling foraminifera to reconstruct the vertical δ18O gradient throughout the eastern equatorial Pacific. We find the thermocline …


Writing And Designing A Chapter On Mercury And Pluto For The Textbook Exploring The Planets (Explanet.Info), Braxton Clark Spilker 2018 Brigham Young University

Writing And Designing A Chapter On Mercury And Pluto For The Textbook Exploring The Planets (Explanet.Info), Braxton Clark Spilker

Theses and Dissertations

Exploring the Planets (http://explanet.info) is a free online college textbook covering thebasic concepts of planetary science emphasizing the character and evolution of the planetarybodies in the Solar System. The latest edition (3rd edition) was published online in 2007 by EricH Christiansen. Since the release of the third edition, two important planetary missions havebeen completed: MESSENGER (to Mercury) and New Horizons (to Pluto). These missionsprovided new information and fundamental insights into these planetary bodies, which have notyet been included in Exploring the Planets. The modern results based on recent investigations ofMercury and Pluto are critical for our understanding of the nature …


Ice And Guano Deposits In El Malpais Lava Tubes: Potential Paleoclimate Archives For The Southwest United States, Dylan S. Parmenter 2018 University of South Florida

Ice And Guano Deposits In El Malpais Lava Tubes: Potential Paleoclimate Archives For The Southwest United States, Dylan S. Parmenter

USF Tampa Graduate Theses and Dissertations

Three ice cores and one guano core were obtained from lava tubes in El Malpais National Monument, New Mexico, in the Southwest United States. A large hiatus in the Bat Cave guano record, resulting from mining activities in the early 1900's, left us with only ~50 years of data (from AD 1955-2006) to use in analysis. 13C values in guano (-18 to -11.6‰) primarily fall within the range of C4 plants, and likely indicate a tendency of Tadarida brasiliensis to feed on insects over grasslands to the North or South of the park. Variations in 13C values for this period …


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 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, Blake Odom 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 …


Morphodynamics Of Shell Key And Mullet Key Barrier Islands: Their Origin And Development, Zachary J. Westfall 2018 University of South Florida

Morphodynamics Of Shell Key And Mullet Key Barrier Islands: Their Origin And Development, Zachary J. Westfall

USF Tampa Graduate Theses and Dissertations

Shell Key and Mullet Key are two sandy barrier islands on the West Central Florida coast near the mouth of Tampa Bay. These islands are part of an interconnected barrier-inlet system that includes Pass-a-Grille (PAG) and Bunces Pass. Shell Key is a relatively new island about 40-years of age that formed in between the two inlets of Bunces Pass and PAG. Mullet Key is an island to the south of Shell Key situated between Bunces Pass and the main Tampa Bay channel that has demonstrated large scale upward shoaling events. Using numerical modeling, the wave and tidal conditions at the …


Crustal Seismic Anisotropy Of The Ruby Mountains Core Complex And Surrounding Northern Basin And Range, Justin T. Wilgus 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 …


New Borehole Breakout Derived Stress Constraints And Their Implications For Stress Heterogeneity Near High Risk Fault Systems In The Santa Barbara Channel, Southern California, Edward Harris Pritchard 2018 Louisiana State University and Agricultural and Mechanical College

New Borehole Breakout Derived Stress Constraints And Their Implications For Stress Heterogeneity Near High Risk Fault Systems In The Santa Barbara Channel, Southern California, Edward Harris Pritchard

LSU Master's Theses

The Santa Barbara Channel represents the offshore portion of the Ventura Basin in Southern California. Ongoing transpression related to a regional left step in the San Andreas Fault has led to the formation of E-W trending en-echelon fault systems, with both north and south dips, which accommodate varying rates of localized shortening across the basin. Recent studies have suggested that faults within the northern region of the channel could be capable of a multisegment rupture and producing a Mw 7.7–8.1 tsunamigenic earthquake. However, dynamic rupture models producing these results have not accounted for stress heterogeneity, which is …


A Regional Survey Of River-Plume Sedimentation On The Mississippi River Delta Front, Andrew J. Courtois 2018 Louisiana State University and Agricultural and Mechanical College

A Regional Survey Of River-Plume Sedimentation On The Mississippi River Delta Front, Andrew J. Courtois

LSU Master's Theses

Many studies of the Mississippi River Delta (MRD) have shown historic declines in sediment load over the last few decades. Recent studies also reported that ~50% of the suspended load during floods is sequestered within the delta. While the impact of declining sediment load on wetland loss is relatively well documented, submarine sedimentary processes on the delta front during this recent period of are understudied. To better understand modern sediment dispersal and deposition across the Mississippi River Delta Front, 31 multicores were collected in June 2017 from locations extending offshore from the main river outlets in water depths of 25-280 …


Application Of Image Recognition Technology To Foraminiferal Assemblage Analyses, Christian Helmut Gfatter 2018 University of South Florida

Application Of Image Recognition Technology To Foraminiferal Assemblage Analyses, Christian Helmut Gfatter

USF Tampa Graduate Theses and Dissertations

Analyses of foraminiferal assemblages involve time consuming microscopic assessment of sediment samples. Image recognition software, which systematically matches features within sample images against an image library, is widely used in contexts ranging from law enforcement to medical research. At present, scientific applications such as identification of specimens in plankton samples utilize flow through systems in which samples are suspended in liquid and pass through a beam of light where the images are captured using transmitted light. Identification of foraminifers generally utilizes reflected light, because most shells are relatively opaque.

My goal was to design and test a protocol to directly …


The Sedimentology And Origins Of A Giant Mass Transport Complex: The Nataraja Slide, Arabian Sea, Sarah Dailey 2018 Louisiana State University and Agricultural and Mechanical College

The Sedimentology And Origins Of A Giant Mass Transport Complex: The Nataraja Slide, Arabian Sea, Sarah Dailey

LSU Master's Theses

A giant mass transport complex (MTC) was recently discovered in the eastern Arabian Sea exceeding in volume all but one other known complex on passive margins worldwide. The complex, named the Nataraja Slide, was drilled by IODP Expedition 355 in two locations where it is ~300 m (Site U1456) and ~200 m thick (Site U1457). The top is defined by the presence of both reworked microfossil assemblages and deformation structures, such as folding and faulting. The deposit consists of two main phases of mass wasting, each which consists of smaller pulses, with generally fining upward cycles, all emplaced just prior …


Osl-Irsl Ages Of Two, Perhaps Three, Pre-Bonneville Deep-Water Pluvial Lakes In Cache Valley, Utah-Idaho: Implications Of Their Unexpected High Altitudes For Excavation Of Cutler Narrows From A Level Above 1494 M (4901 Ft), Down To The Present Level Of 1314 M (4310 Ft) Mainly During The Bonneville Lake Cycle, Robert Q. Oaks Jr., Susanne U. Jänecke, Tammy M. Rittenour, Thad L. Erickson, Michelle S. Nelson 2018 Utah State University

Osl-Irsl Ages Of Two, Perhaps Three, Pre-Bonneville Deep-Water Pluvial Lakes In Cache Valley, Utah-Idaho: Implications Of Their Unexpected High Altitudes For Excavation Of Cutler Narrows From A Level Above 1494 M (4901 Ft), Down To The Present Level Of 1314 M (4310 Ft) Mainly During The Bonneville Lake Cycle, Robert Q. Oaks Jr., Susanne U. Jänecke, Tammy M. Rittenour, Thad L. Erickson, Michelle S. Nelson

Geosciences Faculty Publications

Pluvial-lake highstands in the Bonneville basin are known to be contemporaneous with periods of Quaternary glaciation. At least five lake cycles have been identified from prior studies of two deep cores (Eardley and Gvosdetsky, 1960; Eardley and others, 1973) and several isolated outcrops in the main part of the Bonneville basin and eastward in Cache Valley. These are the Lava Creek B (~620 ka, marine isotope stage MIS 16), Pokes Point (~420 ka, MIS12), Little Valley (~150 ka, MIS 6), Cutler Dam (~60 ka, MIS 4), and Bonneville (~18 ka, MIS 2) lake cycles (Oviatt and others ,1987, 1999; Lisiecki …


Cache Valley: A Critical Part Of Lake Bonneville Preserves Evidence For A Protracted Bonneville Highstand, Possible Tectonic Triggers Of The Bonneville Flood, Liquefaction, And Clustered Earthquakes On The East And West Cache Fault Zones, Susanne U. Jänecke, Robert Q. Oaks Jr., Tammy M. Rittenour, A. J. Knight, Justin Oakeson, Nathan Ellis 2018 Utah State University

Cache Valley: A Critical Part Of Lake Bonneville Preserves Evidence For A Protracted Bonneville Highstand, Possible Tectonic Triggers Of The Bonneville Flood, Liquefaction, And Clustered Earthquakes On The East And West Cache Fault Zones, Susanne U. Jänecke, Robert Q. Oaks Jr., Tammy M. Rittenour, A. J. Knight, Justin Oakeson, Nathan Ellis

Geosciences Faculty Publications

Geologic, geomorphic, and geophysical analyses of landforms, sediments, and structures in conjunction with new radiocarbon (14C) and optically stimulated luminescence (OSL) age determinations document a revised history of flooding and recession of Lake Bonneville in Cache Valley, Idaho and Utah. The presence of wave-cut cliffs in bedrock throughout the Bonneville basin show that the Bonneville highstand was protracted. Triangular facets were cut into bedrock in the footwalls of normal faults, and were steepened significantly by wave erosion at the highest Bonneville shoreline.


The Bear River's Diversion, The Cutting Of Oneida Narrows At 55-50 Ka, And Relations To The Lake Bonneville Record, Joel Pederson, Tammy M. Rittenour, Susanne U. Jänecke, Robert Q. Oaks Jr. 2018 Utah State University

The Bear River's Diversion, The Cutting Of Oneida Narrows At 55-50 Ka, And Relations To The Lake Bonneville Record, Joel Pederson, Tammy M. Rittenour, Susanne U. Jänecke, Robert Q. Oaks Jr.

Geosciences Faculty Publications

The Bear River's course has shifted over Quaternary time, and its late Pleistocene integration into the Bonneville basin long has been recognized as a possible explanation for why Lake Bonneville was apparently larger than the preceding lakes in its basin, and the only one to overflow its topographic threshold.

The middle-Pleistocene Bear River joined the Snake River to the north, likely via the Portneuf River drainage. Then an episode of volcanism in the Blackfoot-Gem Valley volcanic field ~100–50 ka diverted the Bear River southward into Gem Valley. Previous chronostratigraphic and isotopic work on the Main Canyon Formation in southern Gem …


Geologic Mapping Of Nebraska: Old Rocks, New Maps, Fresh Insights, R. Matthew Joeckel, Robert F. Diffendal Jr., P. R. Hanson, Jesse T. Korus 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 …


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