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A Bayesian Nonlinear Inversion Of Seismic Body-Wave Attenuation Factors, Stephen S. Gao 2017 Missouri University of Science and Technology

A Bayesian Nonlinear Inversion Of Seismic Body-Wave Attenuation Factors, Stephen S. Gao

Stephen S. Gao

It is a well-known fact that the uncertainties in measuring relative attenuation factors within a local or regional seismic network are usually high, due to noise of different kinds and unrealistic assumptions. Numerical experiments using nine synthetic seismograms, created using t* values ranging from 0.1 to 0.9 sec, reveal that the commonly used spectral ratio method is strongly affected by the selection of data processing parameters such as width of the spectral smoothing window, reference station, and so on. The numerical experiments demonstrate that a Bayesian nonlinear inversion approach that directly matches the spectra is better at finding ...


Estimation Of The Depth Of Anisotropy Using Spatial Coherency Of Shear-Wave Splitting Parameters, Kelly H. Liu, Stephen S. Gao 2017 Missouri University of Science and Technology

Estimation Of The Depth Of Anisotropy Using Spatial Coherency Of Shear-Wave Splitting Parameters, Kelly H. Liu, Stephen S. Gao

Stephen S. Gao

Shear-wave splitting (SWS) analyses are essential in understanding the structure and dynamics of the Earth's deep interior. While splitting measurements have excellent horizontal resolution relative to other anisotropy-measuring techniques, their vertical resolution is low due to the steep incidence angle of the seismic phases used by the analyses. Here, using synthetic and real data, we present and test a simple approach to estimate the optimal depth of anisotropy by measuring the spatial coherency of the splitting parameters. The approach searches for the optimal depth by computing a spatial variation factor. Tests using synthetic SWS data produced with varying number ...


Nonmarine Time-Stratigraphy In A Rift Setting: An Example From The Mid-Permian Lower Quanzijie Low-Order Cycle Bogda Mountains, Nw China, Jonathan Obrist-Farner, Wan Yang 2017 Missouri University of Science and Technology

Nonmarine Time-Stratigraphy In A Rift Setting: An Example From The Mid-Permian Lower Quanzijie Low-Order Cycle Bogda Mountains, Nw China, Jonathan Obrist-Farner, Wan Yang

Jonathan Obrist-Farner

Sedimentological and stratigraphic studies of seven stratigraphic sections of Permian Hongyanchi (HYC) and Quanzijie (QZJ) low-order cycles (LCs) in the Tarlong-Taodonggou half graben and Dalongkou area in Bogda Mountains, NW China, demonstrate effective approaches and methodology in cyclo- and time-stratigraphic analyses of complex fluvial-lacustrine deposits in an intracontinental rift setting. A new synchronous stratigraphic unit, the lower QZJ LC is defined. The lower and upper boundaries of this cycle include a regionally correlative disconformity, erosional unconformity, and conformity, across which significant and abrupt changes in palaeoenvironments and tectonic and climatic conditions occurred. The lower boundary is an erosional unconformity and ...


Origin And Stratigraphic Architecture Of The Middle Permian Lower And Upper Quanzijie Low-Order Cycles, Bogda Mountains, Nw China, Jonathan Obrist-Farner 2017 Missouri University of Science and Technology

Origin And Stratigraphic Architecture Of The Middle Permian Lower And Upper Quanzijie Low-Order Cycles, Bogda Mountains, Nw China, Jonathan Obrist-Farner

Jonathan Obrist-Farner

"This study is carried out in the Bogda Mountains, NW China, and aims to provide a detailed sedimentary, stratigraphic, environmental, and paleoclimatic reconstruction in the paleo-mid-latitude along the east coast of Pangea. The Middle Permian lower and upper Quanzijie low-order cycles (QZJ LCs) provide a nearly complete sedimentary record in an area were little is known. In the first part of this work, the previously-established QZJ LC is divided into two LCs on the basis of regional stratigraphic correlation and major changes in depositional environments and tectonic and climatic processes. The newly-established lower QZJ LC is mainly composed of meandering ...


Sequence Stratigraphy And Depositional Facies Of Lower Ordovician Cyclic Carbonate Rocks, Southern Missouri, U.S.A., Robert Brandon Overstreet, Francisca Oboh-Ikuenobe, Jay M. Gregg 2017 Missouri University of Science and Technology

Sequence Stratigraphy And Depositional Facies Of Lower Ordovician Cyclic Carbonate Rocks, Southern Missouri, U.S.A., Robert Brandon Overstreet, Francisca Oboh-Ikuenobe, Jay M. Gregg

Francisca Oboh-Ikuenobe

Lower Ordovician cyclic carbonate strata of southern Missouri were deposited in a warm, shallow, epeiric sea on a fully aggraded carbonate platform. Sedimentological characteristics distinguish the Jefferson City and Cotter dolomites from the underlying Gasconade and Roubidoux formations. Mixed carbonate-siliciclastic sedimentation characterizes the Roubidoux Formation, with sandstones accounting for up to 60% of sedimentation. The Gasconade, Jefferson City, and Cotter dolomites exhibit an increased occurrence of chalcedonic chert nodules in very similar shape and texture to the gypsum and anhydrite nodules common on modern sabkha supratidal flats. Casts of halite and ghosts of gypsum laths also exist in the Jefferson ...


Sedimentology Of Acid Saline Lakes In Southern Western Australia: Newly Described Processes And Products Of An Extreme Environment, Kathleen Counter Benison, Brenda Beitler Bowen, Francisca Oboh-Ikuenobe, Elliot A. Jagniecki, Deidre A. LaClair, Stacy L. Story, Melanie R. Mormile, BoYoung Hong 2017 Missouri University of Science and Technology

Sedimentology Of Acid Saline Lakes In Southern Western Australia: Newly Described Processes And Products Of An Extreme Environment, Kathleen Counter Benison, Brenda Beitler Bowen, Francisca Oboh-Ikuenobe, Elliot A. Jagniecki, Deidre A. Laclair, Stacy L. Story, Melanie R. Mormile, Boyoung Hong

Francisca Oboh-Ikuenobe

Naturally acid saline systems with pH values between 1.7 and 4 are common on the Yilgarn Craton of southern Western Australia. a combination of physical and chemical processes here yield a previously undescribed type of modern sedimentary environment. Flooding, evapoconcentration, desiccation, and eolian transport at the surface, as well as influx of acid saline groundwaters, strongly influence these lakes. Halite, gypsum, kaolinite, and iron oxides precipitate from acid hypersaline lake waters. Shallow acid saline groundwaters affect the sediments of the lakes and associated mudflats, sandflats, channels, and dunes by precipitating early diagenetic halite, gypsum, iron oxides, clays, jarosite, and ...


Sedimentary Processes And Products Of Ephemeral Acid Saline Lakes In Southern Western Australia, Francisca Oboh-Ikuenobe, Elliot A. Jagniecki, D. A. LaClair, Stacy L. Story, Melanie R. Mormile, B. Hong, Kathleen C. Benison, Brenda Beitler Bowen 2017 Missouri University of Science and Technology

Sedimentary Processes And Products Of Ephemeral Acid Saline Lakes In Southern Western Australia, Francisca Oboh-Ikuenobe, Elliot A. Jagniecki, D. A. Laclair, Stacy L. Story, Melanie R. Mormile, B. Hong, Kathleen C. Benison, Brenda Beitler Bowen

Francisca Oboh-Ikuenobe

No abstract provided.


Base-Level Buffers And Buttresses: A Model For Upstream Versus Downstream Control On Fluvial Geometry And Architecture Within Sequences, John M. Holbrook, Robert W. Scott, Francisca Oboh-Ikuenobe 2017 Missouri University of Science and Technology

Base-Level Buffers And Buttresses: A Model For Upstream Versus Downstream Control On Fluvial Geometry And Architecture Within Sequences, John M. Holbrook, Robert W. Scott, Francisca Oboh-Ikuenobe

Francisca Oboh-Ikuenobe

The effects of downstream base-level control on fluvial architecture and geometry are well explored in several broadly similar sequence-stratigraphic models. Cretaceous Dakota Group strata, U.S. Western Interior, have characteristics reflecting combined downstream and upstream base-level controls that these models cannot address. Particularly, three layers of amalgamated channel-belt sandstone within this group thicken and are continuous for distances (≤ 300 km) along dip that stretch the reasonable lengths for which these models are intended to apply. As well, architecture in up-dip reaches records repeated valley-scale cut-and-fill cycles. This contrasts with equivalent strata down dip which record channel-scale lateral migration with no ...


Paleogeography Of Early Paleozoic Laurentia And Meguma, Avalonia Terranes Via Paleomagnetism And Faunal Review, Halima S. Warsame 2017 The University of Western Ontario

Paleogeography Of Early Paleozoic Laurentia And Meguma, Avalonia Terranes Via Paleomagnetism And Faunal Review, Halima S. Warsame

Electronic Thesis and Dissertation Repository

Paleomagnetic assessment of 821 Cambrian to Silurian-aged rock specimens of igneous and sedimentary origin was used as a means to provide insight on the ancient geographies of the region in which these rocks are currently found. The Earth’s magnetic field direction can be recorded at the time of rock formation and/or at a later significant event by magnetic minerals, allowing these signatures to be used to track the past motions of the continents. Stepwise demagnetization of the Port au Port, St. George and Table Head Groups in western Newfoundland, and the Mavillette gabbro (426 +/- 2 Ma, U-Pb baddeleyite ...


Faust, Burton Sherwood, 1898-1967 (Mss 620), Manuscripts & Folklife Archives 2017 Western Kentucky University

Faust, Burton Sherwood, 1898-1967 (Mss 620), Manuscripts & Folklife Archives

MSS Finding Aids

Finding aid only for Manuscripts Collection 620. Correspondence, research notes, drafts, photographs, reference works and bibliographic material of Burton S. Faust relating to his studies of the chemical, historical and cultural aspects of saltpetre and of spelean saltpetre mining in the United States.


Assessing The Periodic Groundwater Flow Conditions Of A Perched Aquifer System In The Daniel Boone National Forest, Ethan Sweet 2017 Murray State University

Assessing The Periodic Groundwater Flow Conditions Of A Perched Aquifer System In The Daniel Boone National Forest, Ethan Sweet

Posters-at-the-Capitol

Assessing the Periodic Groundwater Flow Conditions of a Perched Aquifer System in the Daniel Boone National Forest

Ethan Sweet and Jonathan Malzone

Eastern Kentucky University, Department of Geosciences

Natural ephemeral wetlands situated among the ridge-tops in the Daniel Boone National Forest serve as reservoirs that recharge a shallow groundwater system. Unique interactions between surface and groundwater in these isolated systems provide substantial support for the native ecosystem, serving as a breeding ground for amphibians and as source water for vegetation—especially in periods of drought. Currently it is not understood how groundwater could provide regional biodiversity, a drought buffer, or ...


A Study Of Marine Terrace Formation Along The California Central Coast, Mary C. Devlin 2017 California Polytechnic State University, San Luis Obispo

A Study Of Marine Terrace Formation Along The California Central Coast, Mary C. Devlin

Natural Resources Management and Environmental Sciences

Marine terrace formation is in many instances attributed to wave action, and shore platforms are often called “wave-cut”. However, alternative models for marine terrace formation suggest that other types of physical and chemical weathering have a more central role in the formation of marine terraces than is widely acknowledged. Roering and Retallack (2012) concluded that the roles of subaerial physical and chemical weathering are significant, and played a major role in the formation of the terraces. In this study, weathering of beach cliffs and shore platforms associated with marine terraces at eight sites in two different locations along the central ...


An Integrated Analysis Of The Oppliger And Harkness Oil Fields Using Well Log Data And 3d Seismic Data, Casey B. Langdon 2017 Fort Hays State University

An Integrated Analysis Of The Oppliger And Harkness Oil Fields Using Well Log Data And 3d Seismic Data, Casey B. Langdon

Master's Theses

Subsurface mapping from well points and 3D seismic interpretation are essential techniques used to study and locate structures in petroleum exploration. In this study, subsurface structure maps, detailed well log facies analysis, 3D seismic interpretation, and attribute analysis were used to map a Mississippian interval and middle Pennsylvanian age interval from two oil fields in Ness County, Kansas. The objective of this study is to analyze formation properties and facies distribution, map middle Pennsylvanian Cherokee channel deposits using seismic data, and to construct a structural model highlighting important features effecting oil production. Results show that the stratigraphic succession of this ...


The Sequence Stratigraphic Context Of Mixed Basin Margin Evaporites In The Harrisburg Member Of The Permian Kaibab Formation, Northern Arizona And Southern Utah, Cole Hendrickson 2017 Stephen F. Austin State University

The Sequence Stratigraphic Context Of Mixed Basin Margin Evaporites In The Harrisburg Member Of The Permian Kaibab Formation, Northern Arizona And Southern Utah, Cole Hendrickson

Electronic Theses and Dissertations

The Kaibab Formation is a mixed carbonate system including evaporites and siliciclastics deposited on a westward dipping epeiric carbonate ramp during the middle Permian in northern Arizona, southern Utah, and eastern Nevada. It consists of the Fossil Mountain Member deposited in open-marine conditions and the overlying Harrisburg Member deposited in restricted conditions. The Harrisburg Member includes facies and depositional environments ranging from open-marine shallow-subtidal wackestone - packstone, restricted subtidal dolomitic mudstone, dolomitic sandstone, peritidal oolitic grainstone as well as gypsum and red siltstones deposited in a sabkha environment.

Fourteen stratigraphic sections were measured across northern Arizona and southern Utah to analyze ...


A Framework For Incorporating The Impact Of Water Quality On Water Supply Stress: An Example From Louisiana, David M. Borrok, Jian Chen, Hisham Eldardiry, Emad Habib 2017 Missouri University of Science and Technology

A Framework For Incorporating The Impact Of Water Quality On Water Supply Stress: An Example From Louisiana, David M. Borrok, Jian Chen, Hisham Eldardiry, Emad Habib

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Water of poor quality can directly impact the budget of water available for key user groups. Despite this importance, methods for quantifying the impact of water quality on water availability remain elusive. Here, we develop a new framework for incorporating the impact of water quality on water supply by modifying the Water Supply Stress Index (WaSSI). We demonstrate the usefulness of the framework by investigating the impact of high salinity waters on the availability of irrigation water for agriculture in Louisiana. The WaSSI was deconstructed into sectoral components such that the total available water supply could be reduced for a ...


Raritan Formation (Upper Cretaceous), Long Island, New York: Sedimentological And Geochemical Assessment, Nazrul I. Khandaker, Arif Sikder, Stanley Schleifer, Xin-Chen Liu, Carlos E. Castano Londano, Joseph B. McGee Turner 2017 CUNY York College

Raritan Formation (Upper Cretaceous), Long Island, New York: Sedimentological And Geochemical Assessment, Nazrul I. Khandaker, Arif Sikder, Stanley Schleifer, Xin-Chen Liu, Carlos E. Castano Londano, Joseph B. Mcgee Turner

Publications and Research

The lithology of the Upper Cretaceous Raritan Formation (RF) consists of two members: an upper clay member (Raritan clay) and a lower unit, the Lloyd Sand Member. RF is unconformably overlain by upper Pleistocene glacial deposits. The RF consists of stratified white, light- to dark-gray, and red beds and lenses of clay, silt, and sand; lignite and pyrite are common. Variegated, thin to thickly-bedded Lloyd sandstone (LS) is considered to be one of the extensive regional aquifers in Long Island and interpreted to be nearshore, fluvio-deltaic deposit. Proximity to fluvial axes and active deltaic lobes plays an important role in ...


Further Study Of Garnet Xenocrysts In New York City Migmatites, Stanley Schleifer, Nazrul I. Khandaker 2017 York College CUNY

Further Study Of Garnet Xenocrysts In New York City Migmatites, Stanley Schleifer, Nazrul I. Khandaker

Publications and Research

The authors have previously published an article at the 2004 Geological Society of America Annual Meeting, Petrogenetic Significance of Garnets in the Bedrock of New York City, in which they suggested that the garnet xenocrysts observed in the quartzofeldspathic zones of the migmatites, so frequently seen both at the surface, and below the surface pursuant to the construction of the Manhattan portion of New york City Water Tunnel #3, were a refractory residue of the anatectic melting of the immediately surrounding schistose bedrock. Although the relatively high melting point temperature of garnet compared to other minerals in the surrounding schists ...


Experiential Learning Opportunity (Elo) And Utilization Of Field-And-Data- Based Information Obtained Through The Infusion Of Technology: Highlights On Nasa Stem And Earth Science Curricula, Nazrul I. Khandaker, Matthew Khargie, Shuayb Siddiqu, Sol De Leon, Katina Singh, Newrence Wills, Krishna Mahibar 2017 CUNY York College

Experiential Learning Opportunity (Elo) And Utilization Of Field-And-Data- Based Information Obtained Through The Infusion Of Technology: Highlights On Nasa Stem And Earth Science Curricula, Nazrul I. Khandaker, Matthew Khargie, Shuayb Siddiqu, Sol De Leon, Katina Singh, Newrence Wills, Krishna Mahibar

Publications and Research

There is a greater emphasis on hands-on involvement and critical thinking skills in the geosciences and other STEM fields to inspire and engage K- 16 students to value scientific content and enable them to discover the well-documented nature of the fundamental scientific principles needed to explain various earth science and other STEM-related core phenomena. NASA MAA curricula are ideal for engaging K1-16 students in this context, since grade-specific lesson plans open-up a plethora of pedagogically sound and relevant earth science activities. These include earth’s materials and properties, meteorites, robotics, hot air balloon, flight simulation, star gazing, material science, crystal ...


Geology Of Northeastern Nebraska And Environs: Cedar, Dakota, And Dixon Counties In Nebraska, And Plymouth And Woodbury County In Iowa, Robert Matthew Joeckel, Dana Divine, P.R. Hanson, Leslie M. Howard 2017 University of Nebraska - Lincoln

Geology Of Northeastern Nebraska And Environs: Cedar, Dakota, And Dixon Counties In Nebraska, And Plymouth And Woodbury County In Iowa, Robert Matthew Joeckel, Dana Divine, P.R. Hanson, Leslie M. Howard

Conservation and Survey Division

No abstract provided.


Reference Data Set Of Volcanic Ash Physicochemical And Optical Properties, A. Vogel, S. Diplas, A. J. Durant, A. S. Azar, M. F. Sunding, William I. Rose, A. Sytchkova, C. Bonadonna, K. Krüger, A. Stohl 2017 Norwegian Institute of Air Research

Reference Data Set Of Volcanic Ash Physicochemical And Optical Properties, A. Vogel, S. Diplas, A. J. Durant, A. S. Azar, M. F. Sunding, William I. Rose, A. Sytchkova, C. Bonadonna, K. Krüger, A. Stohl

William I. Rose

Uncertainty in the physicochemical and optical properties of volcanic ash particles creates errors in the detection and modeling of volcanic ash clouds and in quantification of their potential impacts. In this study, we provide a data set that describes the physicochemical and optical properties of a representative selection of volcanic ash samples from nine different volcanic eruptions covering a wide range of silica contents (50–80 wt % SiO2). We measured and calculated parameters describing the physical (size distribution, complex shape, and dense-rock equivalent mass density), chemical (bulk and surface composition), and optical (complex refractive index from ultraviolet to near-infrared wavelengths ...


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