Open Access. Powered by Scholars. Published by Universities.®

Geology Commons™

Open Access. Powered by Scholars. Published by Universities.®

29,940 Full-Text Articles 16,128 Authors 6,782,393 Downloads 178 Institutions

All Articles in Geology

Faceted Search

29,940 full-text articles. Page 83 of 1248.

A Hybrid Algorithm To Dual Sparse Sampling Measurement In Time-Resolved Electromagnetic Near-Field Scanning, Yanming Zhang, Steven Gao, Lijun Jiang 2024 Missouri University of Science and Technology

A Hybrid Algorithm To Dual Sparse Sampling Measurement In Time-Resolved Electromagnetic Near-Field Scanning, Yanming Zhang, Steven Gao, Lijun Jiang

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Time-resolved electromagnetic near-field scanning is vital for antenna measurement and addressing complex electromagnetic interference and compatibility issues. However, the swift acquisition of high-resolution spatiotemporal data remains challenging due to physical constraints, such as moving the probe position and allowing sufficient time for sampling. This paper introduces a novel hybrid approach that combines Kriging for sparse spatial measurement, compressed sensing (CS) for sparse temporal sampling, and dynamic mode decomposition (DMD) for a comprehensive analysis of dual-sparse sampling electromagnetic near-field data. CS optimizes sparse sampling in the time domain, capitalizing on the inherent sparsity within electromagnetic radiated signals, resulting in reliable representation …


A Data-Driven Approach To Time-Domain Electromagnetic Modeling Based On Dynamic Mode Decomposition, Yanming Zhang, Steven Gao, Lijun Jiang 2024 Missouri University of Science and Technology

A Data-Driven Approach To Time-Domain Electromagnetic Modeling Based On Dynamic Mode Decomposition, Yanming Zhang, Steven Gao, Lijun Jiang

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

This paper presents a data-driven methodology that utilizes Dynamic Mode Decomposition (DMD) for the time-domain (TD) electromagnetic (EM) modeling of microwave devices. As an unsupervised machine learning technique, DMD leverages a limited set of unlabeled spatio-temporal electromagnetic (EM) data to determine DMD eigenvalues and eigenmodes. Then, the obtained DMD model reconstructs the dynamics as a series of exponential terms based on linear assumptions. The effectiveness of this approach is demonstrated through the TD EM modeling of photonic crystal waveguides. Comparative analysis with the finite-difference time-domain (FDTD) method shows that the DMD model not only achieves precise modeling but also facilitates …


Novel Re-Crosslinkable Preformed Particle Gels (Rppg) For Parent- And Infill-Well-Fracture Interactions Mitigation, Xiaojing Ge, Adel Alotibi, Ahmed Al-Hlaichi, Yanbo Liu, Tao Song, Junchen Liu, Baojun Bai, Thomas P. Schuman 2024 Missouri University of Science and Technology

Novel Re-Crosslinkable Preformed Particle Gels (Rppg) For Parent- And Infill-Well-Fracture Interactions Mitigation, Xiaojing Ge, Adel Alotibi, Ahmed Al-Hlaichi, Yanbo Liu, Tao Song, Junchen Liu, Baojun Bai, Thomas P. Schuman

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Hydraulic fracturing treatments in unconventional infill (or "child") wells can be significantly affected by depletion from existing parent-well, resulting in asymmetrical fracture growth. These issues may lead to excessive load-water production, proppant deposition, casing deformation in the parent well, and unbalanced stimulation of infill wells. To mitigate these effects, various strategies have been proposed, including the use of far-field diverters in child wells and repressurization of parent wells. Additionally, an increasingly popular strategy involves injecting near-wellbore diverters to temporarily plug entry points into the parent wellbores during frac operations on infill wells. To achieve better application, a novel low-cost, self-degradable, …


An Unsupervised Learning Framework For Determining The Excitation Coefficients Using Near-Field Antenna Measurements, Yanming Zhang, Peifeng Ma, Steven Gao, Lijun Jiang 2024 Missouri University of Science and Technology

An Unsupervised Learning Framework For Determining The Excitation Coefficients Using Near-Field Antenna Measurements, Yanming Zhang, Peifeng Ma, Steven Gao, Lijun Jiang

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

This article presents a novel unsupervised learning framework based on multiscale dynamic mode decomposition for determining the excitation coefficients of antennas using time-domain near-field measurements. The proposed framework integrates temporal multiscale analysis to extract a joint distribution of frequency, damping factors, and spatial modes, enabling precise extraction of excitation frequencies, rising/falling edges, and phases without labeled data. We validate the effectiveness of the proposed approach through two examples involving on-off keying modulation and a phase-shift dipole antenna. It is found that the proposed method performs well in handling nonstationary excitation signals and proves particularly advantageous for calibrating tunable antenna systems. …


Descriptive Statistical Analysis Of Experimental Data For Wettability Alteration With Smart Water Flooding In Carbonate Reservoirs, Muhammad Ali Buriro, Mingzhen Wei, Baojun Bai, Ya Yao 2024 Missouri University of Science and Technology

Descriptive Statistical Analysis Of Experimental Data For Wettability Alteration With Smart Water Flooding In Carbonate Reservoirs, Muhammad Ali Buriro, Mingzhen Wei, Baojun Bai, Ya Yao

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Smart water flooding is a promising eco-friendly method for enhancing oil recovery in carbonate reservoirs. the optimal salinity and ionic composition of the injected water play a critical role in the success of this method. This study advances the field by employing machine learning and data analytics to streamline the determination of these critical parameters, which are traditionally reliant on time-intensive laboratory work. the primary objectives are to utilize data analytics to examine how smart water flooding influences wettability modification, identify key parameter ranges that notably alter the contact angle, and formulate guidelines and screening criteria for successful lab design. …


Und-25, Scott Brande 2024 University of Alabama at Birmingham

Und-25, Scott Brande

All 3D Rock Models

Model UND-25 - diorite - igneous rock

SketchFab link: https://sketchfab.com/3d-models/und-25-b0e90e8a6b7c4207a67f070f097b5370


126, Scott Brande 2024 University of Alabama at Birmingham

126, Scott Brande

All 3D Rock Models

Model 126 - basalt - igneous rock

SketchFab link: https://sketchfab.com/3d-models/126-c6ef512294fa4a7ebab143a5260cacbf


131, Scott Brande 2024 University of Alabama at Birmingham

131, Scott Brande

All 3D Rock Models

Model 131 - pumice - igneous rock

SketchFab link: https://sketchfab.com/3d-models/131-f3771991ac1f4864ad7b9a92835042a5


169, Scott Brande 2024 University of Alabama at Birmingham

169, Scott Brande

All 3D Rock Models

Model 169 - chalk - sedimentary rock

SketchFab link: https://sketchfab.com/3d-models/169-0eec274a758747e4b54c37865f5be696


Borneo Stalagmite Evidence Of Significantly Reduced El Niño-Southern Oscillation Variability At 4.1 Kybp, C.M. Theaker, S.A. Carolin, C.C. Day, K.M. Cobb, S. Chen, Pamela R. Grothe, H.O. Couper 2024 University of Mary Washington

Borneo Stalagmite Evidence Of Significantly Reduced El Niño-Southern Oscillation Variability At 4.1 Kybp, C.M. Theaker, S.A. Carolin, C.C. Day, K.M. Cobb, S. Chen, Pamela R. Grothe, H.O. Couper

Earth and Environmental Sciences

The timing and geographic extent of a potential “4.2 ky event” remain highly contested. Here we present records of ENSO variability at 3.8 kyBP and 4.1 kyBP derived from a Borneo stalagmite, which suggest a significant change in ENSO properties between these time intervals. The Borneo records show evidence of significantly reduced ENSO activity at 4.1 kyBP, relative to other measured windows within the Holocene. This reduced ENSO activity coincides with a period of drier conditions and enhanced dust events in the Middle East that took place ∼4.0–4.3 kyBP. The Borneo records show evidence of enhanced ENSO activity at 3.8 …


Assessing Seismic Hazard In Western Kentucky And At The Paducah Gaseous Diffusion Plant: An Overview Of The Issues, Mitigation Strategies, And The Research Conducted By The Kentucky Geological Survey, Zhenming Wang, Seth Carpenter 2024 University of Kentucky

Assessing Seismic Hazard In Western Kentucky And At The Paducah Gaseous Diffusion Plant: An Overview Of The Issues, Mitigation Strategies, And The Research Conducted By The Kentucky Geological Survey, Zhenming Wang, Seth Carpenter

Bulletin--KGS

The exposure of homes, infrastructure, and critical facilities in western Kentucky, including the Paducah Gaseous Diffusion Plant (PGDP), to potential strong seismic shaking from the New Madrid Seismic Zone (NMSZ) has been a major impetus for decades of effort to characterize seismic hazards by the Kentucky Geological Survey (KGS). The purpose of this report is to provide 1) a summary of the earthquake hazards that affect Kentucky and KGS’s ongoing earthquake research, including seismic monitoring, 2) background on the types of seismic hazards in general and how they are quantified in seismic hazard assessments, including strengths and weaknesses of the …


Surficial Geologic Map Of The Bowling Green South 7.5-Minute Quadrangle, Kentucky, Matthew Massey, Meredith Swallom, Bailee Nicole Hodelka, Hannah Hayes, Charles Wells III, Steven L. Martin, Emily Morris 2024 University of Kentucky

Surficial Geologic Map Of The Bowling Green South 7.5-Minute Quadrangle, Kentucky, Matthew Massey, Meredith Swallom, Bailee Nicole Hodelka, Hannah Hayes, Charles Wells Iii, Steven L. Martin, Emily Morris

Contract Reports--KGS

The Kentucky Geological Survey (KGS), a state-supported independent research center within the University of Kentucky, is committed to providing accurate and unbiased geologic information on natural resources, environmental issues, and natural hazards in Kentucky. While Kentucky boasts complete coverage by 1:24,000-scale geologic bedrock maps, surficial materials have been largely overlooked, except in regions with thick deposits obscuring the bedrock. Given the increasing trends in economic development and urbanization, detailed surficial geologic mapping has become crucial for supporting geotechnical planning, environmental management, and hazard assessment. In response, KGS has prioritized new, detailed surficial geologic mapping since 2004, specifically targeting areas anticipated …


Surficial Geologic Map Of The Bristow 7.5-Minute Quadrangle, Kentucky, Bailee Nicole Hodelka, Matthew Massey, Meredith Swallom, Steven L. Martin, Charles Wells III, Emily Morris 2024 University of Kentucky

Surficial Geologic Map Of The Bristow 7.5-Minute Quadrangle, Kentucky, Bailee Nicole Hodelka, Matthew Massey, Meredith Swallom, Steven L. Martin, Charles Wells Iii, Emily Morris

Contract Reports--KGS

The Kentucky Geological Survey (KGS), a state-supported independent research center within the University of Kentucky, is committed to providing accurate and unbiased geologic information on natural resources, environmental issues, and natural hazards in Kentucky. While Kentucky boasts complete coverage by 1:24,000-scale geologic bedrock maps, surficial materials have been largely overlooked, except in regions with thick deposits obscuring the bedrock. Given the increasing trends in economic development and urbanization, detailed surficial geologic mapping has become crucial for supporting geotechnical planning, environmental management, and hazard assessment. In response, KGS has prioritized new, detailed surficial geologic mapping since 2004, specifically targeting areas anticipated …


Multi-Jurisdictional Hazard Mitigation Plan For Landslides For The Big Sandy Area Development District, Kentucky, Matt M. Crawford, Hudson J. Koch, Jason M. Dortch 2024 University of Kentucky

Multi-Jurisdictional Hazard Mitigation Plan For Landslides For The Big Sandy Area Development District, Kentucky, Matt M. Crawford, Hudson J. Koch, Jason M. Dortch

Contract Reports--KGS

Landslides are a complex geologic hazard that occurs worldwide, impacting lives, infrastructure, and property. The Big Sandy Area Development District, Kentucky incurs high landslide activity impacting several municipalities. This hazard mitigation planning project includes landslide susceptibility and risk assessments for the Big Sandy Area Development District. We based the landslide susceptibility model on statistics of hillslope morphological features such as slope, curvature, roughness, aspect, and elevation. Using a dual machine learning approach, we modeled the probability of landslide occurrence, defined as an area that is occupied, or might be occupied in the future, by a landslide. We also developed the …


Subsurface Mapping Of Intra-Arbuckle Shale In North-West Kansas Using Well Log Data, Cole M. Denny 2024 Fort Hays State University

Subsurface Mapping Of Intra-Arbuckle Shale In North-West Kansas Using Well Log Data, Cole M. Denny

Master's Theses or Doctor of Nursing Practice

The aim of this research was to enhance knowledge of Intra-Arbuckle Shale (IAS) distribution and structure through new maps, cross sections, and well log correlations. Understanding the shale(s) ultimately advances the discernment of complex Arbuckle reservoirs that are critical to the Kansas petroleum industry. IAS has been intercepted by oil wells throughout Kansas, but this study focuses on their presence in portions of Ellis, Rooks, Graham, and Trego counties. To study the distribution and structure of IAS, data from micro-resistivity and gamma ray well logs were collected from more than three hundred Arbuckle oil and gas wells. On each well …


Multiple Lithologies In Camel Donga 003 (Ck3): Implications For The Cv Parent Body, Elana Alevy 2024 Colby College

Multiple Lithologies In Camel Donga 003 (Ck3): Implications For The Cv Parent Body, Elana Alevy

Honors Theses

Carbonaceous chondrites record primitive physical and chemical conditions of the solar nebula. In addition, samples of these meteorites provide information about secondary processing due to thermal metamorphism or aqueous alteration on the meteorite’s parent asteroid. Currently, there is debate regarding the number of parent asteroids that the Vigarano-like (CV) and the Karoonda-like (CK) chondrites originate from, which can be addressed through detailed mineralogical and petrographic analysis of samples from these groups.

In this work, we analyzed a thin section of Camel Donga 003, which is currently classified as a CK3 chondrite. Using scanning electron microscopy and electron probe microanalysis, we …


4500-Year Paleohurricane Record From The Western Gulf Of Mexico, Coastal Central Tx, Usa, Sarah B. Monica, Davin J. Wallace, Elizabeth J. Wallace, Xiaojing Du, Sylvia G. Dee, John B. Anderson 2024 University of Southern Mississippi

4500-Year Paleohurricane Record From The Western Gulf Of Mexico, Coastal Central Tx, Usa, Sarah B. Monica, Davin J. Wallace, Elizabeth J. Wallace, Xiaojing Du, Sylvia G. Dee, John B. Anderson

OES Faculty Publications

Texas receives the second-highest number of tropical cyclone (TC) landfalls per year in the United States. At present, long-term TC projections from climate models remain uncertain due to the short and biased nature of Atlantic TC observations. Sediment archives of past storms can help extend the observational record of TC strikes over the past few millennia. When a TC makes landfall along the central Texas coast, coastal downwelling channels and storm currents transport and deposit coarse sediment to a zone of rapid accumulation along the shelf, known as the Texas Mud Blanket (TMB). This “backwash” process results in expansive storm …


Ice-Marginal Volcanic Sequence In Iceland Found On A Nondescript Gradual Hillslope: An Unexpected Record Of Ice Thickness Late In Deglaciation, Audrey R. Putnam, Kristen L. Siebach, Candice C. Bedford, Sarah L. Simpson, Michael T. Thorpe, Joseph J. Tamborski 2024 Rice University

Ice-Marginal Volcanic Sequence In Iceland Found On A Nondescript Gradual Hillslope: An Unexpected Record Of Ice Thickness Late In Deglaciation, Audrey R. Putnam, Kristen L. Siebach, Candice C. Bedford, Sarah L. Simpson, Michael T. Thorpe, Joseph J. Tamborski

OES Faculty Publications

Volcanism increases when glaciers melt because isostatic rebound during deglaciation decreases the pressure on the mantle, which enhances decompression melting. Anthropogenic climate change is now causing ice sheets and valley glaciers to melt around the world and this deglaciation could stimulate volcanic activity and associated hazards in Iceland, Antarctica, Alaska, and Patagonia. However, current model predictions for volcanic activity associated with anthropogenic deglaciation in Iceland are poorly constrained, in part due to uncertainties in past volcanic output over time compared to ice sheet arrangements. Further work specifically characterizing glaciovolcanic and ice-marginal volcanoes in Iceland is needed to reconstruct volcanic output …


Geomorphological Evolution Of The Mun River, Surin Province Northeastern Thailand, Chutiwat Sawangkit 2024 Faculty of Science

Geomorphological Evolution Of The Mun River, Surin Province Northeastern Thailand, Chutiwat Sawangkit

Chulalongkorn University Theses and Dissertations (Chula ETD)

From 1973 to 2023, the Mun River in Surin Province, Thailand, underwent geomorphological evolution. This study examines changes in channel parameters to determine how human activity and natural processes affect river shape. This study measures changes in four important geomorphological parameters channel sinuosity, radius of curvature, channel width, and channel length by analyzing the data from C (ERT), satellite imagery, and topographic maps. A dynamic meandering process that has created oxbow lakes, neck and chute cut-offs, and other geomorphological features throughout time is visible on satellite photos. Significant morphological changes have been brought about, notably, by the building of dams, …


144, Scott Brande 2024 University of Alabama at Birmingham

144, Scott Brande

All 3D Rock Models

Model 144 - obsidian - igneous rock

SketchFab link: https://sketchfab.com/3d-models/144-a362edff33d84ca2b108ef7dc304d745


Digital Commons powered by bepress