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Articles 61 - 90 of 59502

Full-Text Articles in Earth Sciences

An Improved Brittleness Characterization Method For Deep Coalbed Methane Reservoirs And Its Application To Well Logs, Huang An’Er, Gong Fei, Peng Suping, Zou Guangui, Zhang Zhaoji, Wu Yiquan, Rong Zhihong, Li Qingrun Sep 2026

An Improved Brittleness Characterization Method For Deep Coalbed Methane Reservoirs And Its Application To Well Logs, Huang An’Er, Gong Fei, Peng Suping, Zou Guangui, Zhang Zhaoji, Wu Yiquan, Rong Zhihong, Li Qingrun

Coal Geology & Exploration

Background Deep coalbed methane (CBM) reservoirs are characterized by high pressure, low porosity, and low permeability. Therefore, large-scale volume fracturing is required for their commercial development. As an important engineering sweet spot parameter for selecting optimal fracturing targets, the brittleness index can reflect the difficulty in generating complex fracture networks during fracturing. However, existing brittleness characterization methods are largely applicable to strata with high brittle mineral content, such as shales and sandstones, while methods for characterizing the brittleness of deep CBM reservoirs with high organic matter content and low brittle mineral content are lacking. Methods Rock physics experiments on 20 …

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A Fault Identification Method For Deep Coalbed Methane Reservoirs Based On An Improved Transunet, Gao Congshun, Wu Haibo, Liu Lei, Wang Zijian, Huang Xuanyu, Jia Lilan, Xu Aiguo Sep 2026

A Fault Identification Method For Deep Coalbed Methane Reservoirs Based On An Improved Transunet, Gao Congshun, Wu Haibo, Liu Lei, Wang Zijian, Huang Xuanyu, Jia Lilan, Xu Aiguo

Coal Geology & Exploration

Objective Small-scale faults in deep coalbed methane (CBM) reservoirs significantly affect CBM enrichment and the deployment of development wells. However, deep seismic data tend to suffer from low signal-to-noise ratios (SNRs) and poor continuity of reflection events, while conventional methods are likely to miss small-scale faults. To address these limitations, this study proposes a fault identification method based on an improved TransUNet. Methods The proposed method is developed based on the R50-ViT-B_16 TransUNet architecture. A coordinate attention (CA) module is introduced before the skip connections enter the decoder to enhance the feature representation of the locations and directional continuity of …

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Petrophysical Model-Driven Seismic Inversion For Physical Property Parameters Of Deep Coalbed Methane Reservoirs, Chen Yang, Guo Qiang, Ba Jing Sep 2026

Petrophysical Model-Driven Seismic Inversion For Physical Property Parameters Of Deep Coalbed Methane Reservoirs, Chen Yang, Guo Qiang, Ba Jing

Coal Geology & Exploration

Objective Deep coalbed methane (CBM) reservoirs typically exhibit complex pore-fracture structures, as well as strong nonlinear and non-unique corresponding relationships between elastic and physical property parameters. In this context, this study develops a seismic petrophysical inversion method that accounts for pore structure variations. Methods This study investigated deep CBM reservoirs along the eastern margin of the Ordos Basin. First, a petrophysical model based on variable pore aspect ratios was established, and the corresponding linearized forward operator was derived. Then, the pore aspect ratios were estimated using near-borehole log data. Meanwhile, the multimodal prior distributions of reservoir physical property parameters were …

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Intelligent Identification Of Deep Coal Macrolithotypes Based On Weighted Ensemble In Machine Learning: A Case Study Of The Shenmu Area, Ordos Basin, Yao Yuhao, Yang Zhaobiao, Huang Daojun, Wang Jianan, Dong Guodong, Chen Yilin, He Jinxian, Zhang Shang Sep 2026

Intelligent Identification Of Deep Coal Macrolithotypes Based On Weighted Ensemble In Machine Learning: A Case Study Of The Shenmu Area, Ordos Basin, Yao Yuhao, Yang Zhaobiao, Huang Daojun, Wang Jianan, Dong Guodong, Chen Yilin, He Jinxian, Zhang Shang

Coal Geology & Exploration

Objective Coal macrolithotype represents a key geological property in the exploration and recovery of deep coalbed methane (CBM) resources, and its accurate identification is of great significance for selecting the optimal geological and engineering sweet-spot intervals. However, conventional coal macrolithotype identification relies heavily on core observation, suffering from prohibitively high costs since core data are extremely valuable and thus feature a small sample size. Meanwhile, conventional log-based threshold methods face challenges in effectively characterizing the complex boundaries between coal macrolithotypes.Methods This study investigated the No. 8 coal seam of the Benxi Formation, Shenmu area, eastern Ordos Basin. Based on …

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A Probabilistic Lithofacies Classification Method For Deep Coal Measures, Xu Aiguo, Zhang Pingsong, Wu Haibo, Li Shenglin Sep 2026

A Probabilistic Lithofacies Classification Method For Deep Coal Measures, Xu Aiguo, Zhang Pingsong, Wu Haibo, Li Shenglin

Coal Geology & Exploration

Background Deep coal measures contain multiple unconventional reservoir types, including coal, shale, and tight sandstone. Accurate lithofacies classification helps identify the resource and engineering targets of unconventional gas within these deep sequences, thus guiding category-based extraction and efficient development. However, conventional lithofacies classification methods largely rely on elastic parameters derived based on the isotropic-medium assumption or linear amplitude variation with offset (AVO) inversion while neglecting the pronounced vertical transverse isotropy (VTI) anisotropy of deep coal measures, severely limiting the lithofacies classification accuracy. Methods This study develops a probabilistic lithofacies classification method for deep coal measures. First, high-accuracy elastic parameters, including …

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Multi-Round Diverting Fracturing Technology For Deep-Seated Thin Coal Seams And Its Application: A Case Study Of The G3-1 Well Group In The Yichuan Block, Ordos Basin, Li Shuguang, Nie Zhihong, Ji Liang, Zhou Changhui, Bai Kunsen, Huang Li, Zhen Huaibin, Xing Xuejie, Zhao Haifeng Sep 2026

Multi-Round Diverting Fracturing Technology For Deep-Seated Thin Coal Seams And Its Application: A Case Study Of The G3-1 Well Group In The Yichuan Block, Ordos Basin, Li Shuguang, Nie Zhihong, Ji Liang, Zhou Changhui, Bai Kunsen, Huang Li, Zhen Huaibin, Xing Xuejie, Zhao Haifeng

Coal Geology & Exploration

Objective Deep coal seams in the Yichuan block of the Ordos Basin are characterized by small thicknesses, vertical multi-layer superimposition, and strong vertical and horizontal heterogeneities. When used to develop these coal seams, multi-stage horizontal well fracturing faces challenges such as uneven fracture propagation across various stages in the horizontal direction and a low production degree of multiple coal seams in the vertical direction, complicating commercial exploitation. To address these issues, this study proposes a multi-round diverting fracturing technology based on a vertical cluster well group. In this technology, vertical layered fracturing using vertical cluster wells is employed to achieve …

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Scaling And Blockage In Deep Coalbed Methane Wells: Mechanisms And Countermeasures, Zhang Lei, Chen Ming, Zhen Huaibin, Zeng Wenting, Hao Pengcheng, Hou Wei, Yin Decai, Zhang Kang, Liu Chuanqing, Tian Zhida, Liu Qihu, Wang Qian, Xiong Wei, Sun Weiwei, Xia Fei, Wang Chunyan Sep 2026

Scaling And Blockage In Deep Coalbed Methane Wells: Mechanisms And Countermeasures, Zhang Lei, Chen Ming, Zhen Huaibin, Zeng Wenting, Hao Pengcheng, Hou Wei, Yin Decai, Zhang Kang, Liu Chuanqing, Tian Zhida, Liu Qihu, Wang Qian, Xiong Wei, Sun Weiwei, Xia Fei, Wang Chunyan

Coal Geology & Exploration

Background The exploitation of deep coalbed methane (CBM) is accompanied by continuous pressure drawdown. In this case, scaling and blockage are prone to occur in systems where formation water with high total dissolved solids (TDS) and high-concentration CO2 coexist. In the middle to late production stage, the blockage of both wellbore and flow pathways in reservoirs frequently leads to abrupt declines in gas production and bottomhole pressure or even induces the shutdown of natural flowing production, severely restricting the stable production of deep CBM wells. Methods This study investigated the Daning-Jixian block in the eastern Ordos Basin. Using multiple …

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Technology Roadmap And Countermeasures For Lean Development Of Low-Grade Deep Coalbed Methane: A Case Study Of The Linxing-Shenfu Block, Ordos Basin, Wu Guang’Ai, Xing Xuesong, Wu Jianshu, Zhu Ying, Zi Jingyu, Wang Zhi, Hou Yanan, Cheng Yuxiong, Liu Xin Sep 2026

Technology Roadmap And Countermeasures For Lean Development Of Low-Grade Deep Coalbed Methane: A Case Study Of The Linxing-Shenfu Block, Ordos Basin, Wu Guang’Ai, Xing Xuesong, Wu Jianshu, Zhu Ying, Zi Jingyu, Wang Zhi, Hou Yanan, Cheng Yuxiong, Liu Xin

Coal Geology & Exploration

Background Accelerating deep coalbed methane (CBM) exploitation is a strategic initiative for the energy security and energy mix optimization of China. The Linxing-Shenfu block in the Ordos Basin holds considerable resource potential of deep CBM. However, this block exhibits typical geological characteristics of low-grade deep CBM, including the complete absence of free gas, gas content < 14 m3/t, reservoir permeability < 0.1 × 10−3 μm2, and strong heterogeneity. These characteristics lead to low efficiency of conventional development models. Therefore, there is an urgent need to develop an efficient technical system tailored to these characteristics. Method To address the core contradiction between reservoir …

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Numerical Simulation Of Stress Shadow Effect And Cluster Spacing Optimization For Multi-Cluster Fracturing In Deep Coalbed Methane Horizontal Wells, Guo Guangshan, Deng Zhiyu, Sun Le, Pu Yifan, Wu Jian, Tao Shu, Chen Shaojuan, Chen Shida Sep 2026

Numerical Simulation Of Stress Shadow Effect And Cluster Spacing Optimization For Multi-Cluster Fracturing In Deep Coalbed Methane Horizontal Wells, Guo Guangshan, Deng Zhiyu, Sun Le, Pu Yifan, Wu Jian, Tao Shu, Chen Shaojuan, Chen Shida

Coal Geology & Exploration

Purpose Multi-stage, multi-cluster fracturing in horizontal wells represents a key technique for deep coalbed methane (CBM) recovery and the sustainable development of the industry. However, during multi-cluster fracturing in deep CBM horizontal wells, the stress shadow effect tends to induce non-uniform fracture propagation and a limited stimulated reservoir volume (SRV). Methods To address these challenges. this study established a two-dimensional (2D) numerical model for multi-cluster hydraulic fracturing in horizontal wells using the finite element method. Then, it systematically analyzed the impacts of in situ stress and cluster spacing on both the stress shadow effect and the competitive propagation of hydraulic …

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Fracturing With Three-Dimensional Full-Scale Fracture Network Propping For Deep Coalbed Methane Reservoirs: A Novel Ceramic Micro-Proppant And Its Verification Through Numerical Simulations, Li Xiang, Xu Jun, Li Ting, Zhang Xiaoyu, Yang Bo Sep 2026

Fracturing With Three-Dimensional Full-Scale Fracture Network Propping For Deep Coalbed Methane Reservoirs: A Novel Ceramic Micro-Proppant And Its Verification Through Numerical Simulations, Li Xiang, Xu Jun, Li Ting, Zhang Xiaoyu, Yang Bo

Coal Geology & Exploration

Objective and Methods Conventional fracturing struggles to achieve the long-term effective propping of complex fracture networks during the development of deep coalbed methane (CBM) reservoirs. To address this challenge, this study developed a novel ceramic micro-proppant suitable for the volumetric microfracture propping and, through numerical simulations, verified its performance when it was applied to reservoir stimulation in conjunction with the technology of fracturing with three-dimensional full-scale fracture network propping. First, a novel ceramic micro-proppant with a core-shell structure was designed according to the requirements of microfracture propping. Its key properties, including compressive strength, settling behavior, hydraulic conductivity, and stability, were …

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A Spatiotemporal Surrogate Model And Multi-Objective Optimization For Multi-Well Coalbed Methane Production, Qin Yuancheng, Wang Mengyi, Wang Yanfeng, Li Yuan, He Bo, Fang Junling, Duan Qingshan, Liu Chen Sep 2026

A Spatiotemporal Surrogate Model And Multi-Objective Optimization For Multi-Well Coalbed Methane Production, Qin Yuancheng, Wang Mengyi, Wang Yanfeng, Li Yuan, He Bo, Fang Junling, Duan Qingshan, Liu Chen

Coal Geology & Exploration

Objective and Methods In the full-lifecycle optimization of multi-well and long-term coalbed methane (CBM) production, conventional numerical simulation methods face challenges including extremely high computational costs and difficult multi-objective trade-offs. To address these issues, this study proposed a spatiotemporal surrogate model for multi-objective optimization of CBM production. First, a heterogeneous reservoir model involving 17 production wells was constructed based on high-fidelity numerical simulation, and a sample dataset was created by applying random perturbations to the baseline production scheme. Second, a hybrid surrogate model integrating a convolutional neural network (CNN) and a Transformer decoder was established. The CNN was utilized for …

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Numerical Simulation And Process Optimization Of Multi-Round Fracturing In Deep Coalbed Methane Wells In The Linxing-Shenfu Block, Li Yu, Zhang Liang, Li Yunyun, An Qi, Feng Xuesong, Lan Tian, Yu Ji, Liu Xin Sep 2026

Numerical Simulation And Process Optimization Of Multi-Round Fracturing In Deep Coalbed Methane Wells In The Linxing-Shenfu Block, Li Yu, Zhang Liang, Li Yunyun, An Qi, Feng Xuesong, Lan Tian, Yu Ji, Liu Xin

Coal Geology & Exploration

Objective Deep coalbed methane (CBM) holds considerable resource potential. However, deep CBM reservoirs exhibit high in-situ stresses, while deep coals feature strong plasticity and heterogeneity. These characteristics render it challenging to generate complex fracture networks through conventional fracturing, thus restricting the large-scale commercial development of deep CBM resources. Multi-round fracturing enables fracture initiation, propagation, and propping through sequential cycles of fracturing fluid injection, pump shut-in, and injection. By constantly changing near-wellbore stress fields, this technique facilitates the formation of complex fracture networks and ensures uniform reservoir stimulation. Method Using the finite-discrete element method (FDEM), this study established a numerical model …

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Factors Influencing Non-Perennial Stream Initiation In The Mt. Hood National Forest, Allison Bast Sep 2026

Factors Influencing Non-Perennial Stream Initiation In The Mt. Hood National Forest, Allison Bast

Dissertations and Theses

Historically, non-perennial headwater streams have been overlooked due to their small size and infrequent flow regimes, often leading to them not being recognized as legitimate streams, despite scientific evidence that has shown these streams significantly affect the quality of downstream waters. To combat this issue, environmental managers need to be able to accurately identify and delineate the origins of these streams; however, despite decades of research, an accurate, universal method for predicting how and where these streams commence has yet to be developed. Early studies conducted in steep, humid environments, identified a strong inverse linear relationship between the size of …

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A Deep Learning-Based Approach For Mapping Shrubs In Arctic Tundra From Very High-Resolution Imagery, Darko Radakovic, Mark Chopping, Bruce Cook, Aparna S. Varde, Stefan A. Robila Sep 2026

A Deep Learning-Based Approach For Mapping Shrubs In Arctic Tundra From Very High-Resolution Imagery, Darko Radakovic, Mark Chopping, Bruce Cook, Aparna S. Varde, Stefan A. Robila

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Arctic shrub expansion is accelerating due to climate warming, but accurately mapping it at fine spatial scales remains challenging due to spectral overlap between shrubs and surrounding vegetation, heterogeneous tundra landscapes, and limited availability of very high-resolution imagery. This study presents a novel mapping and validation approach that integrates very high-resolution (< 1 m) QuickBird (QB) and WorldView (WV) satellite imagery across 12 North Slope sites, using deep learning architectures to map changes in shrub cover from 2002 to 2022. Deep learning models, including Convolutional Neural Network (CNN), ResNet, VGG, U-Net, and Vision Transformer, were trained on 4,100 3-channel pansharpened multispectral images (200×200 m). Two traditional machine learning models (Random Forest and Support Vector Machine) served as a control group. Leave-one-site-out cross-validation showed that all models performed well (AUC-ROC of 0.78–0.86, F1 at validation of 0.33-0.46) and had a moderate to strong agreement with field reference data (R2 = 0.76–0.87). The pretrained VGG and ResNet models achieved the strongest field-reference alignments for shrub cover prediction, while the difference with traditional models was small. Temporal trend analyses for July and August demonstrate a cover change of 0.06–0.45% yr-1 with unweighted mean area slopes and 0.01–0.92% yr-1 inverse-variance weighting. Growth rates were found to depend on the analytical design. Furthermore, the limiting factor in mapping shrub cover was not model complexity but the quality of the training data labels (annotation method explained ∼26% of the error variance). Per-scene cover error was seen across architectures (ρ = 0.67). Comparison with NASA Goddard's LiDAR, Hyperspectral and Thermal (G-LiHT)-derived Canopy Height Models revealed a weak-to-moderate relationship (R2 = 0.04–0.77), suggesting horizontal cover and vertical canopy structure capture complementary aspects of shrub abundance. These results demonstrate the potential of deep learning to map decadal shrub expansion at sub-meter resolution.

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The Fragmentation Of Helcar: A Paratethyan Model For Rhûn, Núrnen And The Dead Marshes, Federico Manzoni Sep 2026

The Fragmentation Of Helcar: A Paratethyan Model For Rhûn, Núrnen And The Dead Marshes, Federico Manzoni

Journal of Tolkien Research

This work proposes a conjectural paleogeographic model linking the Sea of Rhûn, Núrnen and the Dead Marshes to the former Sea of Helcar. Beginning from Christopher Tolkien's suggestion that Rhûn may represent Helcar ``vastly shrunken,'' the study combines textual evidence, the Ambarkanta, Fonstad's cartographic reconstructions, and terrestrial analogues drawn from the evolution of the Paratethys, the Messinian Salinity Crisis and other endorheic basins. Helcar is interpreted not merely as an isolated body of deep water but as the centre of a broader hydrological province subsequently partitioned by relief change, sedimentary infilling, basin isolation and drainage reorganization. Within this model, Rhûn …

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Selective Citation: The Systematic Omission Of Established Regional Literature, İrem Eli̇tez Sep 2026

Selective Citation: The Systematic Omission Of Established Regional Literature, İrem Eli̇tez

Turkish Journal of Earth Sciences

No abstract provided.

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Integrated Assessment Of Groundwater Quality And Human Health Risks In A Semiarid Region Of Kemaliye (Türkiye), Veli̇ Keski̇n, Celaletti̇n Şi̇mşek Sep 2026

Integrated Assessment Of Groundwater Quality And Human Health Risks In A Semiarid Region Of Kemaliye (Türkiye), Veli̇ Keski̇n, Celaletti̇n Şi̇mşek

Turkish Journal of Earth Sciences

In this study, the hydrochemical characteristics, drinking water suitability, and potential human health risks of groundwater in the Karapınar region (Kemaliye, Erzincan, Türkiye), which has become a critical drinking water resource due to drought associated with climate change and the depletion of surface water resources, were investigated using an integrated multiparameter approach. Within the scope of the study, a total of 18 water samples, comprising 13 spring water samples and 5 groundwater samples obtained from wells, were collected during the dry season (October 2021) and analyzed for major ions, physicochemical parameters, nitrate, and trace elements. The suitability of the samples …

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Signals In The Ionosphere Ahead Of Tsunami Arrival, Svetlana Riabova, Sergey Shalimov Sep 2026

Signals In The Ionosphere Ahead Of Tsunami Arrival, Svetlana Riabova, Sergey Shalimov

Turkish Journal of Earth Sciences

We consider the impact of the tsunami propagating after the earthquake in Tohoku on the ionosphere according to measurements from the Hawaiian Islands, i.e., at a fairly large distance from the epicenter of the earthquake. These measurements, taken at a tidal tsunami monitoring station, at a magnetometric station, and by GPS, were used to record the arrival of the tsunami. We experimentally establish that the arrival of atmospheric waves generated by the tsunami significantly advanced the arrival of sea waves at the observation point, and this advance from one source was recorded in both the lower and upper ionosphere. Attention …

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Editorial Note To The Article “Identification Of A Previously Unrecognized Listric Fault Beneath The Acıpayam Graben: Insights From Integrated Dinsar And Field Observations” [Turkish Journal Of Earth Sciences 35 (1) 2026 20-41], Orhan Tatar Sep 2026

Editorial Note To The Article “Identification Of A Previously Unrecognized Listric Fault Beneath The Acıpayam Graben: Insights From Integrated Dinsar And Field Observations” [Turkish Journal Of Earth Sciences 35 (1) 2026 20-41], Orhan Tatar

Turkish Journal of Earth Sciences

No abstract provided.

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Possible Fluid Contributions From Active Faults To Mercury Distribution In Surface Sediments Of The Gemlik Gulf And Health Risk Assessment, Erol Sari, M. Namik Çağatay, Tuğçe Nagi̇han Arslan Kaya, Zeynep Çeti̇n, Nuray Çağlar Sep 2026

Possible Fluid Contributions From Active Faults To Mercury Distribution In Surface Sediments Of The Gemlik Gulf And Health Risk Assessment, Erol Sari, M. Namik Çağatay, Tuğçe Nagi̇han Arslan Kaya, Zeynep Çeti̇n, Nuray Çağlar

Turkish Journal of Earth Sciences

The Gemlik Gulf, located in the eastern part of the Sea of Marmara (Türkiye), is recognized as a relatively contaminated marine environment, influenced by a variety of natural and anthropogenic inputs. A comprehensive geochemical study was performed to examine the distribution of total mercury (THg) in surface sediments and to elucidate the possible sources contributing to its accumulation. The analysis revealed that THg concentrations ranged from 485 to 6486 ng/g, with all measured values substantially exceeding the average shale background concentration of 400 ng/g, indicating significant enrichment. According to sediment quality guidelines, none of the samples exceeded the effects range …

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Paleoecology Of Loftusia Species (Large Benthic Foraminifera) In The Zagros Basin, North Of The Neotethys, Hossein Ghanbarloo, Amrollah Safari Sep 2026

Paleoecology Of Loftusia Species (Large Benthic Foraminifera) In The Zagros Basin, North Of The Neotethys, Hossein Ghanbarloo, Amrollah Safari

Turkish Journal of Earth Sciences

Paleoecological analyses based on the wall structure of the genus Loftusia were carried out in the Maastrichtian deposits of seven outcrops of the Zagros Basin. Two types of particles are present within the wall structure: (1) tiny fossil grains and (2) detrital grains. Tiny fossil grains consist of smaller foraminifera and other small microorganism tests. Foraminiferal tests are associated with miliolid, textulariid, and rotaliid forms. Detrital grains include intraclasts and extraclasts. The presence of different particles in the test wall of this genus and the abundance of this genus in nutrient-rich conditions indicate that Loftusia are probably opportunistic foraminifera. This …

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Neoproterozoic Uranium-Mineralized Sedimentary Rocks From The Kaladgi Basin, Dharwar Craton, Southwestern India: Source And Transport Mechanism Of Uranium, Ponnalagu Govindaraj, Arumugam Shanmugasundaram, Sooriamuthu Ramasamy, Muthusamy Ravichandran Sep 2026

Neoproterozoic Uranium-Mineralized Sedimentary Rocks From The Kaladgi Basin, Dharwar Craton, Southwestern India: Source And Transport Mechanism Of Uranium, Ponnalagu Govindaraj, Arumugam Shanmugasundaram, Sooriamuthu Ramasamy, Muthusamy Ravichandran

Turkish Journal of Earth Sciences

The Kaladgi Basin of the Dharwar Craton, southeast India, hosts Proterozoic unconformity-related uranium (U) mineralization controlled by faulted contacts between Archean basement and Proterozoic cover sediments. To understand the ore-forming processes, 25 core samples from the Cave Temple Arenite were analyzed using whole-rock geochemistry and fluid inclusion microthermometry. U concentrations reach up to 0.13% U3O8 in the basal arenite and lower conglomerate, whereas the basement schist records only 0.0017% U. Whole-rock data reveal high SiO2 contents (72–97 wt.%), variable Al2O3 (0.4–12.9 wt.%), and enrichments in U (0.38–6.63 ppm), Th (1.5–13.7 ppm), and trace elements such as Cu, Pb, and Ni …

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Citation Scope And Scientific Relevance In An Event-Based Seismotectonic Study: Reply To The Comment By Elitez On Eski (2026), Semi̇h Eski̇ Sep 2026

Citation Scope And Scientific Relevance In An Event-Based Seismotectonic Study: Reply To The Comment By Elitez On Eski (2026), Semi̇h Eski̇

Turkish Journal of Earth Sciences

No abstract provided.

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The Fossil Pearls Of The Million-Pearls Flowstone, Fairgrounds Room, Fort Stanton Cave, New Mexico Usa, Victor J. Polyak, Paula P. Provencio, Yemane Asmerom Sep 2026

The Fossil Pearls Of The Million-Pearls Flowstone, Fairgrounds Room, Fort Stanton Cave, New Mexico Usa, Victor J. Polyak, Paula P. Provencio, Yemane Asmerom

International Journal of Speleology

‘Fossil’ cave pearls in the Fairgrounds Room of Fort Stanton Cave form two distinct layers in a flowstone sample, FS-14-2. The flowstone in the Fairgrounds Room covers a mud-silt bank and the extinct streambed that extends across the room. Uranium-series dates of two pieces of flowstone from this room, one piece from the higher end of the flowstone (FS-14-1, devoid of pearls), and another piece from the lower end of the flowstone (FS-14-2, rich in pearls), show that the flowstone was deposited during the Last Glacial period (60,000 to 11,000 yr BP).  The two cave-pearl layers in FS-14-2 yielded U-series …

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Collaborative Research: Influence Of Fault Frictional Healing And Realistic Tectonic Loading Rates On Shallow Subduction Megathrust Locking, Srisharan Shreedharan Sep 2026

Collaborative Research: Influence Of Fault Frictional Healing And Realistic Tectonic Loading Rates On Shallow Subduction Megathrust Locking, Srisharan Shreedharan

Funded Research Records

No abstract provided.

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"The Course Of The Tennessee River", William Lindsey Mcdonald Sep 2026

"The Course Of The Tennessee River", William Lindsey Mcdonald

Research Articles

The article describes the usual course of the Tennessee River and various geological theories for the direction of its course. In addition, it explores the specific geomorphology of the Muscle Shoals and its impact on North Alabama.

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White Shark Occurrence In Flower Garden Banks National Marine Sanctuary Revealed From Acoustic Telemetry In An Offshore Mpa, Michael A. Dance, Jay R. Rooker, R. J. David Wells, Megan V. Winton, Landes L. Randall, Marissa F. Nuttall, Brondum M. Krebs, Creed C. Branham, Brett B. Sweezey, Richard J. Kline Sep 2026

White Shark Occurrence In Flower Garden Banks National Marine Sanctuary Revealed From Acoustic Telemetry In An Offshore Mpa, Michael A. Dance, Jay R. Rooker, R. J. David Wells, Megan V. Winton, Landes L. Randall, Marissa F. Nuttall, Brondum M. Krebs, Creed C. Branham, Brett B. Sweezey, Richard J. Kline

School of Earth, Environmental, & Marine Sciences Faculty Publications

The outer continental shelf of the Gulf of Mexico (Gulf) is characterized by unique bathymetric features that provide critical habitat for marine fauna. Here, we demonstrate the utility of large-scale acoustic telemetry for monitoring an oceanic marine protected area (MPA) and document the first known occurrences of white sharks (Carcharodon carcharias) within Flower Garden Banks National Marine Sanctuary (FGBNMS). White sharks were tagged with acoustic transmitters in the western North Atlantic Ocean off the east coast of the United States and Canada. Nine white sharks were detected along the outer shelf ecosystem associated with FGBNMS over a three-year …

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Automated And Quantitative Characterization Of Benthic Habitat And Associated Biological Communities Of An Unknown Southeast Pacific Seamount, Yakufu Niyazi, Denise J. B. Swanborn, Jan M. Tapia-Guerra, Javier Sellanes, Erin E. Easton, Germán Zapata-Hernández, Heather A. Stewart, Alan J. Jamieson Sep 2026

Automated And Quantitative Characterization Of Benthic Habitat And Associated Biological Communities Of An Unknown Southeast Pacific Seamount, Yakufu Niyazi, Denise J. B. Swanborn, Jan M. Tapia-Guerra, Javier Sellanes, Erin E. Easton, Germán Zapata-Hernández, Heather A. Stewart, Alan J. Jamieson

School of Earth, Environmental, & Marine Sciences Faculty Publications

Seamounts are prominent seafloor features that strongly influence geological processes, ocean circulation, and benthic biodiversity. Despite their importance, most seamounts remain unmapped and poorly characterized, particularly in the southeast Pacific Ocean, a region recognized for high marine endemism and ecological isolation. In this study, we present a quantitative habitat characterization of a previously undocumented seamount, informally named Solito Seamount, located between the Nazca–Desventuradas Marine Park and the Juan Fernández Archipelago, within Chile’s Exclusive Economic Zone. The seamount is a conical volcanic edifice approximately 37 km wide, rising >3,500 m above the surrounding abyssal plain. High-resolution multibeam bathymetry and backscatter intensity …

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A New Bubblegum Coral From The Nazca Ridge Reveals Chitin As The Structural Scaffold Of Skeleton-Less Paragorgia Colonies, Juan Armando Sánchez, Erin E. Easton, Nayeli Elizavet Garcia, Yony Román-Ochoa, Julia Kaled Cáceres, Javier Sellanes Sep 2026

A New Bubblegum Coral From The Nazca Ridge Reveals Chitin As The Structural Scaffold Of Skeleton-Less Paragorgia Colonies, Juan Armando Sánchez, Erin E. Easton, Nayeli Elizavet Garcia, Yony Román-Ochoa, Julia Kaled Cáceres, Javier Sellanes

School of Earth, Environmental, & Marine Sciences Faculty Publications

Bubblegum corals (Paragorgia; Corallidae) form among the largest branching colonies in deep-sea environments despite lacking an axial skeleton. How these octocorals maintain structural cohesion using only sub-millimeter sclerites has remained unexplained. Here we describe Paragorgia quitinosa Sánchez & Easton n. sp., collected at 670 m depth on the Nazca Ridge (southeastern Pacific) during the Schmidt Ocean Institute RV Falkor (too) expedition FKt240708, and report the first evidence of visible chitin in octocoral tissues. The new species is diagnosed by autozoids and siphonozoids retracted on prominent, rounded mounds, large 8-derived radiate capstan sclerites (mean 0.095 mm), and canal walls …

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Sedimentary Dynamics In Tubular Sandstone Caves, Porto União, Southern Brazil, Leandro Bianchini, Julio Cesar Paisani Sep 2026

Sedimentary Dynamics In Tubular Sandstone Caves, Porto União, Southern Brazil, Leandro Bianchini, Julio Cesar Paisani

International Journal of Speleology

Clastic sedimentation in sandstone caves remains poorly understood, particularly in systems with tubular morphology. This study investigates sedimentation, reworking, and sediment removal dynamics in the Legru Cave system, southern Brazil, based on the integrated analysis of sedimentary facies, microstructures, and microfeatures, combined with optically stimulated luminescence dating. The results indicate that conduit infilling is dominated by high-density flows, including cohesive debris flows, partially diluted multiphase flows, and flows with intermediate rheological behavior between mud flow and hyperconcentrated flow, in addition to shallow flow alternations. Sediment supply is predominantly allochthonous, related to hillslope-derived material delivered by overland flow and mud flows, …

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