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Spatiotemporal Evaluation Of Water Quality, Metal Pollution, And Human Health Risks In A Dredged Urban River, New Jersey, Usa, Oluwafemi Soetan, Qingzhi Zhu, Huan Feng Jun 2025

Spatiotemporal Evaluation Of Water Quality, Metal Pollution, And Human Health Risks In A Dredged Urban River, New Jersey, Usa, Oluwafemi Soetan, Qingzhi Zhu, Huan Feng

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Although the short-term effectiveness of remedial sediment dredging (RSD) on mitigating sediment contamination in the lower Passaic river (LPR), New Jersey, USA, was previously established in previous studies, dredging impacts on overlying water and consequential effects on aquatic life and human health were not investigated through model-based risk assessment methods. This study assessed the influence of RSD on metal pollution and toxicological risks upstream and downstream of River Mile-3.4, which was the subject of a 2012 RSD. Over the pre-, during-, and post-dredging periods, threats to aquatic life and humans were greater upstream at River Mile-4 (WQIavg. ≥ 50, PIavg. …


Sea Turtle Nesting On Nourished Beaches With Different Construction Designs: A Case Study In Southeast Florida, Usa., Lara Novalvos Hernandez Jun 2025

Sea Turtle Nesting On Nourished Beaches With Different Construction Designs: A Case Study In Southeast Florida, Usa., Lara Novalvos Hernandez

USF Tampa Graduate Theses and Dissertations

This study examines the influences of different beach nourishment designs and subsequent post-nourishment profile adjustments on loggerhead (Caretta caretta) and green (Chelonia mydas) sea turtles nest survival and reproductive success. Data on time-series post-nourishment beach-profile changes, positions and elevations of turtle tracks and nest/false-crawl apices, and sea turtle nest hatch/emergence success were collected on five high density nesting beaches along the east coast of Florida: Melbourne Beach, Jensen Beach, Jupiter Island Beach, Juno Beach, and South Hutchinson Island Beach. The field data collection was conducted in 2018, 2019, 2021, and 2022 with the main goal of documenting and comparing turtle …


From The Amazon To The Andes: Paleoclimatic And Paleoenvironmental Changes Recorded By Sedimentary Biomarkers Since The Late Pleistocene, Alessandro Antúnez De Mayolo Mauceri Jun 2025

From The Amazon To The Andes: Paleoclimatic And Paleoenvironmental Changes Recorded By Sedimentary Biomarkers Since The Late Pleistocene, Alessandro Antúnez De Mayolo Mauceri

Arts & Sciences Graduate Student Theses and Dissertations

The South American tropics encompass some of Earth's most diverse and dynamic landscapes, from tropical glaciers and arid deserts to savannahs, shrublands, and the planet’s largest and most biodiverse rainforest—spread across a vast climatic and topographic gradient. These biomes provide vital natural resources that sustain communities, bolster economies, and serve as key components of the global hydrologic and carbon cycles. Despite their environmental and socioeconomic importance, these tropical systems are highly vulnerable to contemporary and future climate change and its cascading impacts. Adding to this challenge, the scarcity and short duration of instrumental climate records from this region pose major …


An Integrated Geophysical Approach For Estimating The Depth Of Mineral Potential In Some Part Of Basement Complex Terrain Southwestern Nigeria, Hamid Titilope Oladunjoye, Joseph Coker, Niyi-Ola Adebisi, Omolara Abosede Adenuga, Sofiat Adetomilola Adekoya, Aderemi Alabi, Abisola Akinmoladun Jun 2025

An Integrated Geophysical Approach For Estimating The Depth Of Mineral Potential In Some Part Of Basement Complex Terrain Southwestern Nigeria, Hamid Titilope Oladunjoye, Joseph Coker, Niyi-Ola Adebisi, Omolara Abosede Adenuga, Sofiat Adetomilola Adekoya, Aderemi Alabi, Abisola Akinmoladun

Al-Bahir

Effective mineral exploration in a basement complex necessitates precise delineation of overburden thickness and mineral potential within the Basement Complex terrain. This study examined the subsurface geology and assesses the abundance of prospective mineral deposits within the study area The objective of the study was to outline the overburden thickness and infer mineral potential using integrated ground magnetic and electrical resistivity geophysical methods. The electrical resistivity method unraveled the litho-stratigraphic sequence as surmised from geo-electric layers. Consequently, the mineralization of the basement delineated was characterized by the magnetic method. The acquired data were processed using WINRESIST and Oasis Montaj respectively. …


Quantifying Wellbore Effects During Co2 Sequestration In A Saline Aquifer, Uzoma Johnpaul Ajugwe Jun 2025

Quantifying Wellbore Effects During Co2 Sequestration In A Saline Aquifer, Uzoma Johnpaul Ajugwe

USF Tampa Graduate Theses and Dissertations

Carbon capture and storage (CCS) is a strategy for mitigating climate change by reducing greenhouse gas emissions from large stationary sources like fossil-fuel-fired power stations. One method of CCS involves carbon dioxide (CO2) sequestration in deep saline aquifers, where supercritical CO2 is injected into an aquifer. The success of such projects depends on accurate predictions of CO2 behavior within the subsurface, which are obtained through numerical simulations.

TOUGHREACT, a renowned simulation tool, models subsurface fluid flow, geochemical interactions, and solute transport, providing insights into the feasibility of CO2 sequestration projects. A critical aspect of these simulations is the apportioning of …


How’S It Growing? Tools For Observing Snow And Sea Ice In A Changing Arctic Ocean, Ian Alexander Raphael Jun 2025

How’S It Growing? Tools For Observing Snow And Sea Ice In A Changing Arctic Ocean, Ian Alexander Raphael

Dartmouth College Ph.D Dissertations

September Arctic sea ice extent has diminished by roughly 50% in the 45 years since satellite observations began. The Arctic Ocean may experience ice-free summers within the next decade, with implications for habitat, resource extraction, geopolitics, and local and global climate change. To predict how Arctic sea ice will change in the future, we need to understand its behavior in the present. In situ sea ice mass balance measurements (snow accumulation, ice growth, snow and ice surface melt, and bottom melt) are essential for studying the processes driving rapid changes in the ice pack, and for validating remote sensing measurements …


Elemental Analysis Of Sediments In Johnson County, Kansas: Applications In Fluvial Suspended Sediment Tracing, Kiena Campbell Jun 2025

Elemental Analysis Of Sediments In Johnson County, Kansas: Applications In Fluvial Suspended Sediment Tracing, Kiena Campbell

Undergraduate Theses, Capstones, and Recitals

This exploratory study investigates whether bulk elemental analysis of sediment samples using inductively coupled mass spectrometry (ICP-MS) can reveal chemical signatures that identify anthropogenic contributions to sedimentation and increased fluvial suspended sediment loads, and whether these contribution sources can be identified. Human activity, urbanization, and changes in land use increase erosion, resulting in higher-than-natural suspended sediments (SS) in waterways and increasing sedimentation in reservoirs across the state of Kansas. These threats to freshwater storage capacity are especially urgent given the projected rise in freshwater demand in the Great Plains region driven by climate change. Understanding the origin of anthropogenic SS …


Great Work Is Done While We Sleep, Julie Wildschut Jun 2025

Great Work Is Done While We Sleep, Julie Wildschut

University Faculty Publications and Creative Works

No abstract provided.


Enhancing Water Scarcity Resilience In Egypt Through Machine Learning-Driven Phenological Crop Mapping And Water Use Efficiency Analysis, Surendra Maharjan, Wenzhao Li, Shahryar Fazli, Aqil Tariq, Rejoice Thomas, Cyril Rakovski, Hesham El-Askary Jun 2025

Enhancing Water Scarcity Resilience In Egypt Through Machine Learning-Driven Phenological Crop Mapping And Water Use Efficiency Analysis, Surendra Maharjan, Wenzhao Li, Shahryar Fazli, Aqil Tariq, Rejoice Thomas, Cyril Rakovski, Hesham El-Askary

Mathematics, Physics, and Computer Science Faculty Articles and Research

Agriculture forms the backbone of Egypt’s economy, with the Nile Valley and Delta serving as key production zones for crops like wheat, rice, and clover. However, the sector faces mounting pressure from water scarcity, as it depends almost entirely on the Nile for irrigation, making it necessary to map major crops for assessing Water Use Efficiency (WUE) and informing agricultural planning. In this study, we used machine learning (ML) techniques—specifically Support Vector Machine (SVM) to time-series phenological data and optical indices (Enhanced Vegetation Index (EVI), Bare Soil Index (BSI), Land Surface Water Index (LSWI), Normalized Difference Vegetation Index (NDVI), and …


Evaluation Of Ecostress Collection 2 Evapotranspiration Products: Strengths And Uncertainties For Evapotranspiration Modeling, Zoe Amie Pierrat, Adam J. Purdy, Gregory Halverson, Joshua B. Fisher, Kanishka Mallick, Madeleine Pascolini-Campbell, Youngryel Rye, Martha C. Anderson, Claire Villanueva-Weeks, Margaret C. Johnson, Brenna Hatch, Evan Davis, Yun Yang, Kerry Cawse-Nicholson Jun 2025

Evaluation Of Ecostress Collection 2 Evapotranspiration Products: Strengths And Uncertainties For Evapotranspiration Modeling, Zoe Amie Pierrat, Adam J. Purdy, Gregory Halverson, Joshua B. Fisher, Kanishka Mallick, Madeleine Pascolini-Campbell, Youngryel Rye, Martha C. Anderson, Claire Villanueva-Weeks, Margaret C. Johnson, Brenna Hatch, Evan Davis, Yun Yang, Kerry Cawse-Nicholson

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The ECOsystem Spaceborne Thermal Radiometer Experiment on Space Station (ECOSTRESS) collects thermal observations from the International Space Station to support evapotranspiration (ET) research at fine spatial resolutions (70 m × 70 m). Initial ET from ECOSTRESS Collection 1 was used in scientific research and applications, though subsequent analyses identified areas for improvement. This study outlines updates to ECOSTRESS Collection 2 ET and presents an accuracy assessment of ET and auxiliary variables validated against in situ data from AmeriFlux. Key updates in Collection 2 include use of four independent model estimates of instantaneous latent energy (LE) and improved auxiliary forcing data. …


Land Instability Compounds The Risk Of Sea Level Rise In Alexandria, Egypt, Rejoice Thomas, Sara Zouriq, Shahryar Fazli, Amr Fawzy, Nikolay Grisel Todorov, Surendra Maharjan, Wenzhao Li, Erik Linstead, Daniele Struppa, Hesham El-Askary Jun 2025

Land Instability Compounds The Risk Of Sea Level Rise In Alexandria, Egypt, Rejoice Thomas, Sara Zouriq, Shahryar Fazli, Amr Fawzy, Nikolay Grisel Todorov, Surendra Maharjan, Wenzhao Li, Erik Linstead, Daniele Struppa, Hesham El-Askary

Mathematics, Physics, and Computer Science Faculty Articles and Research

The coastal region of Alexandria Governorate in Egypt holds significant strategic importance for trade while being susceptible to extreme weather events. It confronts a dual challenge of the rising sea levels and, as found in this study, land instability. While much attention has been rightly directed towards sea level rise (SLR), the stability of the land warrants equal consideration. Here, a comprehensive analysis of land stability is conducted in Alexandria by measuring Line of Sight (LOS) displacements and assessing their topographical, hydrological, and coastal impacts. Persistent Scatterer Interferometry technique is used to measure the LOS displacements in association with land …


Toward Integrated Urban Observatories: Synthesizing Remote And Social Sensing In Urban Science, Danlin Yu Jun 2025

Toward Integrated Urban Observatories: Synthesizing Remote And Social Sensing In Urban Science, Danlin Yu

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Urbanization is reshaping landscapes and posing unprecedented sustainability challenges, necessitating more integrative approaches to urban observation. This review synthesizes recent advancements in traditional remote sensing and emerging social sensing technologies, emphasizing their convergence within urban science. A systematic thematic analysis of 667 peer-reviewed articles highlights the methodological progress, practical applications, and theoretical innovations arising from this integration. Traditional remote sensing effectively captures urban physical features but lacks insights into human behaviors. Conversely, social sensing, leveraging digital traces from social media and mobile data, introduces essential human-centered dimensions into urban monitoring. The fusion of these complementary paradigms through advanced data analytics …


Arkansas Corn And Grain Sorghum Research Studies 2024, Jason Kelley, Travis Faske Jun 2025

Arkansas Corn And Grain Sorghum Research Studies 2024, Jason Kelley, Travis Faske

Arkansas Agricultural Experiment Station Research Series

The 2024 edition of the Arkansas Corn and Grain Sorghum Research Studies Series includes research results on topics pertaining to corn and grain sorghum production, including weed, disease, nematode, and insect management; economics; irrigation; agronomics; soil fertility; drone use; and research verification program results.

Our objective is to capture and broadly distribute the results of research projects funded by the Arkansas Corn and Grain Sorghum Board. The intended audience includes producers and their advisors, current investigators, and future researchers. The Series serves as a citable archive of research results.

The reports inform and guide our long-term recommendations, but should not …


Investigation Of Retention And Dehydration Of Preformed Particle Gel For Conformance Control In Fractured Carbonates, Abdulaziz A. Almakimi, Abdullah O. Almansour, Junchen Liu, Baojun Bai, Ibnelwaleed A. Hussein Jun 2025

Investigation Of Retention And Dehydration Of Preformed Particle Gel For Conformance Control In Fractured Carbonates, Abdulaziz A. Almakimi, Abdullah O. Almansour, Junchen Liu, Baojun Bai, Ibnelwaleed A. Hussein

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Preformed particle gel (PPG) treatment has proved to be among the most effective methods to reduce excessive water production in fractured reservoirs. The blocking ability of PPGs to fractures or fracture-like features is highly dependent on injected gel properties and volume. Gel dehydration during extrusion through fracture is common and has a considerable effect on gel properties, transport, and plugging efficiency. As the gel particles propagate through the fracture, continuous dehydration is often associated and causes the gel to concentrate and require high-pressure gradients to move. Dehydration might be desirable to a certain limit because it can help to form …


Revealing Watery Geologies: Softening The Mississippi River Bluffs In Saint Paul, Minnesota, Chloe Kahn May 2025

Revealing Watery Geologies: Softening The Mississippi River Bluffs In Saint Paul, Minnesota, Chloe Kahn

Masters Theses

How is a place shaped by the geologies beneath it? In Saint Paul, Minnesota, the geologic ground tells the story of the different forces and processes that shaped it through time, but in the most recent geologic period of the anthropocene, industrialization and urban development have covered up these stories. On the edge of downtown, where the city meets the Mississippi River, an eighty foot concrete wall replaces the natural form of the bluff shaped by glacial and riverine activity. This thesis peels back the anthropogenic materials we encounter every day and explores Saint Paul through deep time– exploring how …


Large-Scale Groundwater System Characterization Using Pressure Responses To Barometric Perturbations Caused By The 2022 Hunga Tonga-Hunga Ha'apai Volcanic Eruption, Anhua He, Yang Liu, Fan Zhang, Huamei Zhang, Ramesh P. Singh, Yanzhang Wang May 2025

Large-Scale Groundwater System Characterization Using Pressure Responses To Barometric Perturbations Caused By The 2022 Hunga Tonga-Hunga Ha'apai Volcanic Eruption, Anhua He, Yang Liu, Fan Zhang, Huamei Zhang, Ramesh P. Singh, Yanzhang Wang

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Hunga Tonga-Hunga Ha'apai volcanic erupted on 15 January 2022, causing Lamb waves to propagate throughout the global troposphere. However, reports on volcanic eruptions–pressure fluctuations and water level dynamics are lacking. We quantified the propagation processes of Lamb waves induced by the Tonga volcanic eruption. Barometric pressure data collected at 1-min intervals at 485 meteorological stations in China showed that the eruption induced an atmospheric pressure event with an amplitude of ∼2 hPa over an hour and a wave speed of 295 m/s. Concomitant groundwater levels were available at 338 wells to find the barometric response to the volcanic event. The …


Integrated Geochemical, Geoelectrical, And Uav-Based Methods For Analyzing The Güzelyalı Landslide (Çanakkale, Türkiye), Oya Erenoğlu, Emi̇n Ulugergerli̇, R. Cüneyt Erenoğlu, Abdullah Akbaş, Ahmet Evren Ergi̇nal May 2025

Integrated Geochemical, Geoelectrical, And Uav-Based Methods For Analyzing The Güzelyalı Landslide (Çanakkale, Türkiye), Oya Erenoğlu, Emi̇n Ulugergerli̇, R. Cüneyt Erenoğlu, Abdullah Akbaş, Ahmet Evren Ergi̇nal

Turkish Journal of Earth Sciences

The number of reactivations increased in the Güzelyalı-Erenköy landslide area after 2013 in Çanakkale, Türkiye, where historical landslide activity has been recorded since 1875. This area is home to numerous summer residences and experiences ongoing slow-moving landslide activity along a 400-m-long slope, extending from the heavily trafficked Çanakkale-İzmir highway to the coastline. In this study, the nature of the reactivations was evaluated by considering the conditioning and triggering factors that contributed to the landslide. The evaluation was based on geochemical analyses, field observations, geoelectric measurements, and unmanned aerial vehicle (UAV) data. The results revealed that the sliding occurred along a …


First Record Of Scyphocrinoids In Türkiye And Recognition Of The Silurian/Devonian Boundary Interval (Halevikdere Section, Eastern Taurides), Eberhard Schindler, Reimund Haude, Mehmet Namik Yalçin, Rainer Brocke, Ati̇ke Nazi̇k, Emine Şeker Zor, Volker Wilde, Achim Wehrmann May 2025

First Record Of Scyphocrinoids In Türkiye And Recognition Of The Silurian/Devonian Boundary Interval (Halevikdere Section, Eastern Taurides), Eberhard Schindler, Reimund Haude, Mehmet Namik Yalçin, Rainer Brocke, Ati̇ke Nazi̇k, Emine Şeker Zor, Volker Wilde, Achim Wehrmann

Turkish Journal of Earth Sciences

During the Silurian/Devonian (S/D) boundary interval, scyphocrinoids (Crinoidea, Echinodermata) flourished on a global scale. The first record of scyphocrinoids from Türkiye, especially represented by their bulbuous loboliths, is now described from the Halevikdere Section in the Eastern Taurides. The Devonian part of the section is more than 1300 m thick and covers a time span from the S/D boundary interval to the Late Devonian (Famennian). It consists mainly of fine-grained to sandy siliciclastics, event-driven conglomerates/fanglomerates and biogenic carbonates deposited in deep shelf to shallow-water coastal settings. The S/D boundary interval was measured and studied in great detail. The dominant lithology …


The Quaternary Fluvial-Lacustrine System In The Akarçay Basin (Sw Anatolia): Depositional Environments And Paleoclimatic Interpretation, Koray Aktürk, Sevi̇nç Kapan May 2025

The Quaternary Fluvial-Lacustrine System In The Akarçay Basin (Sw Anatolia): Depositional Environments And Paleoclimatic Interpretation, Koray Aktürk, Sevi̇nç Kapan

Turkish Journal of Earth Sciences

The Akarçay Closed Basin, located in southwest Anatolia, contains deformed formations and the drying Akşehir and Eber lakes. This study aimed to interpret the paleoenvironmental and paleoclimatic conditions of the Akşehir and Eber lakes, which are reported to have been connected during the Pleistocene. Based on sedimentological and mineralogical data, three different depositional subenvironments were defined, corresponding to the formation and development stages of the lake. Sedimentary facies analysis of the Pleistocene deposits in the basin revealed the following facies associations, listed from bottom to top: 1) an alluvial fan and fluvial facies association, representing the formation stage of the …


Formation Of Holocene Paleosols In A Relict Sand Dune Sequence At Kıyıköy, Türkiye, Ahmet Evren Ergi̇nal, Mustafa Bozcu, Nuretti̇n Yakupoğlu, Abdullah Akbaş, Hakan Kaya, İsmai̇l Onur Tunç May 2025

Formation Of Holocene Paleosols In A Relict Sand Dune Sequence At Kıyıköy, Türkiye, Ahmet Evren Ergi̇nal, Mustafa Bozcu, Nuretti̇n Yakupoğlu, Abdullah Akbaş, Hakan Kaya, İsmai̇l Onur Tunç

Turkish Journal of Earth Sciences

The paleoclimatic indicators from a relict dune and paleosol sequence observed south of Kıyıköy Port, NW Türkiye, provide insights into the variable paleoclimatic conditions in the western Black Sea coastal zone over the last 4700 yrs BP. The relict dune- paleosol sequence consists of reddish-brown coarse sands with abundant shells and overlying paleosol. Radiocarbon dating of Donax trunculus shells collected from the lowest part of the relict dune revealed the onset of sand deposition 4689 ± 123 yrs ago. The dark-colored paleosol layer, with an Rb/Sr ratio of 0.008, yielded an age of 287 ± 32 yrs cal BP. These …


U-Pb Calcite Geochronology, Epr, Geochemistry, And C-O-Sr Isotopes Of Africanomarbles In The Seferihisar (İzmir, Türkiye) U-Pb Calcite Geochronology, Epr, Geochemistry, And C-O-Sr Isotopes Of Africano Marbles In The Seferihisar (İzmir, Türkiye), Fatma Şi̇şman Tükel, Namik Aysal, İpek Deni̇z Yildirim, Marcel Guillong, Tonguç Uysal, Si̇nan Öngen, Emre Erdem May 2025

U-Pb Calcite Geochronology, Epr, Geochemistry, And C-O-Sr Isotopes Of Africanomarbles In The Seferihisar (İzmir, Türkiye) U-Pb Calcite Geochronology, Epr, Geochemistry, And C-O-Sr Isotopes Of Africano Marbles In The Seferihisar (İzmir, Türkiye), Fatma Şi̇şman Tükel, Namik Aysal, İpek Deni̇z Yildirim, Marcel Guillong, Tonguç Uysal, Si̇nan Öngen, Emre Erdem

Turkish Journal of Earth Sciences

The Africano marbles (Africano Verde and Bigio Africano) extracted from the region of Sığacık (ancient Teos) region and its surroundings were widely used and even traded in construction and decorative items throughout the Roman period due to their brecciated and colourful appearance. There are two different types of Africano marble, the first consisting of marble breccias embedded in a dark matrix. In this type, the marble breccias show micritic, microsparitic, and sometimes sparitic textures formed by coarse-grained calcite, while the dark matrix consists of chlorite and/or serpentine minerals. The second type is Bigio Africano, which consists of grey-blue homogeneous limestones, …


Calculating Moment Magnitude Using The Coda Calibration Technique To Update The Earthquake Catalog Of Iraq (1900-2021), Muntadher Al-Kaabi May 2025

Calculating Moment Magnitude Using The Coda Calibration Technique To Update The Earthquake Catalog Of Iraq (1900-2021), Muntadher Al-Kaabi

Theses and Dissertations

The first comprehensive earthquake catalog for Iraq based on moment magnitude (Mw) ‎was compiled by Onur et al. (2017). It spanned the period from 1900 until the end of ‎‎2009, covered the region between 26°–40° N latitudes and 36°–51° E longitudes, and ‎included more than 18,000 earthquakes, of which roughly 4,000 are of Mw 4.0 or larger. ‎With the ongoing efforts of updating the probabilistic seismic hazard assessment ‎‎(PSHA) and the Iraqi building code, the need for an updated earthquake catalog for Iraq ‎in terms of moment magnitude (Mw) has been raised. Robust estimation of moment ‎magnitude (Mw) can be …


Mechanisms And Collaborative Prevention And Control Techniques For Various Disasters In Coal Seam Roofs, Zheng Kaige, Zhang Jian, Sun Siqing, Chen Dongdong, Wang Zeyang May 2025

Mechanisms And Collaborative Prevention And Control Techniques For Various Disasters In Coal Seam Roofs, Zheng Kaige, Zhang Jian, Sun Siqing, Chen Dongdong, Wang Zeyang

Coal Geology & Exploration

Objective The multistage sedimentary and tectonic evolution of coal seams in China has led to the formation of environments with the coexistence of multiple disasters including gas outbursts, water inrushes, and rock bursts. To address the chain evolution of these disasters induced by the coupling of high in situ stress, high water pressure, and intense mining under the condition of deep coal mining, this study systematically investigated the coupling mechanisms and collaborative prevention and control techniques of multiple dynamic disasters in coal seam roofs. Methods Based on the regional tectonic characteristics and the delineation of coal-bearing tectonic units, this study …


Mechanisms And Equation Improvement For Gas Seepage In Coal Seams Around Boreholes Subjected To High-Pressure Co2 Foam Fracturing, Pang Mingkun, Zhang Tianyu, Pan Hongyu, Song Xianfeng, Wu Shan, Zhang Tianjun May 2025

Mechanisms And Equation Improvement For Gas Seepage In Coal Seams Around Boreholes Subjected To High-Pressure Co2 Foam Fracturing, Pang Mingkun, Zhang Tianyu, Pan Hongyu, Song Xianfeng, Wu Shan, Zhang Tianjun

Coal Geology & Exploration

Objective The special low-porosity, low-permeability structures of high-gas-content coal seams restrict efficient gas drainage. To address this issue, this study accurately determined the seepage parameters of annularly fractured coals around boreholes subjected to CO2 foam fracturing to enhance both the design accuracy of boreholes for gas pre-drainage from coal seams and gas drainage efficiency. Methods Using an independently developed apparatus for gas seepage experiments on fractured coals around boreholes, this study investigated the coals with pores and fractures distributed in an annular pattern around boreholes from the perspective of varying initial pore structures. Specifically, this study analyzed the evolutionary …


Dominant Geological And Engineering Factors Controlling The Productivity Of Horizontal Wells For Deep Coalbed Methane In The Southern Shenfu Block, Guo Guangshan, Liu Yancheng, Zhao Gang, Chen Zhaohui, Li Chen, Kang Lifang, Wang Yuchuan, Wang Jianan May 2025

Dominant Geological And Engineering Factors Controlling The Productivity Of Horizontal Wells For Deep Coalbed Methane In The Southern Shenfu Block, Guo Guangshan, Liu Yancheng, Zhao Gang, Chen Zhaohui, Li Chen, Kang Lifang, Wang Yuchuan, Wang Jianan

Coal Geology & Exploration

Objective The southern Shenfu block along the eastern margin of the Ordos Basin hosts one of the rare gas fields with reserves of over 100 billion cubic meters (bcm) in China, serving as a pilot demonstration area for the exploration and production of deep coalbed methane (CBM) conducted by the China National Offshore Oil Corporation (CNOOC). In this block, the gas production of horizontal wells is 2-10 times that of vertical wells. However, the horizontal wells are challenged by significantly different and rapidly declining gas production. Determining dominant factors controlling the productivity of horizontal wells for deep CBM is the …


Impacts Of The Hydrochemical Characteristics Of Coal Seam Water On The Structures And Metabolic Functions Of Microbial Communities, Wang Gaohao, Duan Shengjie, Wang Bei, Niu Guobin, Liang Yongping, Yu Feilong, Ma Kai, Zhao Weizhong May 2025

Impacts Of The Hydrochemical Characteristics Of Coal Seam Water On The Structures And Metabolic Functions Of Microbial Communities, Wang Gaohao, Duan Shengjie, Wang Bei, Niu Guobin, Liang Yongping, Yu Feilong, Ma Kai, Zhao Weizhong

Coal Geology & Exploration

Background The core of coalbed methane (CBM) bioengineering is to inject bio-fracturing fluids rich in efficient methanogenic bacteria into coal reservoirs to promote the conversion of coals to methane. However, the relationships of the hydrochemical characteristics of coal seam water with the structures and metabolic functions of microbial communities remain unclear. Methods This study investigated coal seam water from 12 typical mining areas in Ningxia. Based on microbial classification and sequencing, as well as statistical analysis, this study explored the relationships of pH, anions, cations, and chemical oxygen demand (COD) of coal seam water with the structures and metabolic functions …


Construction And Application Of A Model For Drainage Via Directional Boreholes Against Water Hazards In Deep Vertical Shafts, Zhao Chunhu, Zhu Mingcheng, Ji Yadong, Wang Shidong, Zhang Wenzhong, Zhu Kaipeng, Liu Yingfeng, Shang Hongbo, Li Chaofeng, Fan Min, Li Kai May 2025

Construction And Application Of A Model For Drainage Via Directional Boreholes Against Water Hazards In Deep Vertical Shafts, Zhao Chunhu, Zhu Mingcheng, Ji Yadong, Wang Shidong, Zhang Wenzhong, Zhu Kaipeng, Liu Yingfeng, Shang Hongbo, Li Chaofeng, Fan Min, Li Kai

Coal Geology & Exploration

Background Vertical shafts are typically employed in the deep mining areas of Jurassic coalfields in western China. However, the direct exposure of extremely thick Cretaceous aquifers frequently leads to significant water inflow in shafts. Meanwhile, the continuous sand-carrying water inflow and scouring in vertical shafts pose serious safety hazards to the overall quality of shaft walls. Methods In underground water exploration and discharge boreholes, water outlets are below the floors of aquifers to be drained. This allows unpowered water discharge. In other words, water can flow out naturally. By fully leveraging this advantage, combined with the favorable condition of spatial …


Diffusion Mechanisms Of Power-Law Grouts In Water-Rich Sand Layers During Permeation Grouting, Xie Bao, Cheng Hua, Wang Xuesong, Li Mingjing, Liu Xiangyang, Han Xueyu May 2025

Diffusion Mechanisms Of Power-Law Grouts In Water-Rich Sand Layers During Permeation Grouting, Xie Bao, Cheng Hua, Wang Xuesong, Li Mingjing, Liu Xiangyang, Han Xueyu

Coal Geology & Exploration

Objective This study aims to clarify the spherical diffusion patterns of power-law grouts in water-rich sand layers during permeation grouting and their influential factors. To this end, permeation grouting experiments were conducted to gain insights into the quantitative impacts of varying grouting parameters on grout diffusion.Methods Using model experiments on spherical diffusion during permeation grouting, this study analyzed the macroscopic diffusion morphologies and microscopic infilling effects of grouts, as well as the trends of permeation and soil pressures during grouting. Then, based on the spherical diffusion equations for permeation grouting that consider multi-effect coupling, this study analyzed the factors …


A Phase Transition-Induced Fracturing Permeability Enhancement Technology Using Carbon Dioxide Capsules For Low-Permeability Coal Seams And Its Application, Li Mao, Fan Xinchuan, Fu Hui May 2025

A Phase Transition-Induced Fracturing Permeability Enhancement Technology Using Carbon Dioxide Capsules For Low-Permeability Coal Seams And Its Application, Li Mao, Fan Xinchuan, Fu Hui

Coal Geology & Exploration

Objective and Methods To address engineering challenges like high gas content, high pressure, and low drainage efficiency in the mining of low-permeability coal seams, this study developed a phase transition-induced fracturing and permeability enhancement technology using carbon dioxide (CO2) capsules for low-permeability coal seams. This technology leverages the feature that CO2 transitions into the supercritical state under high pressure. A capsule encapsulating critical CO2 is placed into a conduit, which is then placed within a coal seam. Subsequently, phase transition-induced blasting is triggered using a heating blasting start device. Consequently, liquid CO2 vaporizes rapidly and …


Assessing The Potential And Suitability Of Geothermal Resources Using Monte Carlo Simulation And Game-Based Combination Weighting Method, He Yixiang, Ding Pengpeng, Liu Shaohua, Wang Mingzhu, Zhu Lei May 2025

Assessing The Potential And Suitability Of Geothermal Resources Using Monte Carlo Simulation And Game-Based Combination Weighting Method, He Yixiang, Ding Pengpeng, Liu Shaohua, Wang Mingzhu, Zhu Lei

Coal Geology & Exploration

Background Geothermal energy in porous sandstone reservoirs is recognized as stable, efficient clean energy. However, these reservoirs feature heterogeneity and exploration uncertainty, posing serious challenges to probabilistic resource assessment and the identification of suitability for resource development.Methods This study investigated the geothermal resources in the Guantao Formation within the northwest Shandong plain. Using the volumetric method and Monte Carlo simulation, this study assessed the uncertainty of the resource potential. Then, considering the characteristics of geothermal resources, the attributes of geological structures, and the social economy, this study developed a multi-dimensional evaluation index system for the suitability of sandstone geothermal …