Wonderstone And Its Connection To Liesegang, Microbes, And Beyond,
2023
University of Nebraska-Lincoln
Wonderstone And Its Connection To Liesegang, Microbes, And Beyond, Haden S. Mandery
Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research
In the western and southwestern United States, the term wonderstone is used to describe volcanic, volcaniclastic, and sedimentary rocks with variegated banding produced by iron oxide mineralization or staining. This iron oxide mineralization is typically described as Liesegang banding. In this paper I will (1) test if the banding in wonderstone follows the spacing and width laws characteristic of Liesegang, (2) identify the source of iron that ultimately precipitated in the bands, and (3) examine the role that microbes played in the formation of the mineralization in these rocks. I conclude that the iron oxide mineralization is not Liesegang banding. …
Population Demography Of A Glacial-Relict Stream Fish Mediated Via Anthropogenic Alteration,
2023
University of Nebraska-Lincoln
Population Demography Of A Glacial-Relict Stream Fish Mediated Via Anthropogenic Alteration, Joseph M. Spooner
School of Natural Resources: Dissertations, Theses, and Student Research
Northern Pearl Dace Margariscus nachtriebi are a small-bodied glacial-relict fish species of greatest conservation need (SGCN) found throughout Canada and the northern United Sates. Their distribution within the Nebraska Sandhills Ecoregion is isolated from the northern core distribution of the species following the last glaciation period approximately 18,000 years ago. Headwater streams within the Nebraska Sandhills Ecoregion are predominately groundwater fed and provide the cool water temperatures needed to support Northern Pearl Dace and other glacial-relict SGCN. Headwater streams within the Nebraska Sandhills Ecoregion have been geomorphically altered through anthropogenic processes such as channelization whereby habitat homogenization has occurred. Evidence …
Habitat Heterogeneity In Nebraska Streams And Distribution Prediction For Tier-1 Cyprinids Using Multi-Scale Modeling Of Fluvial And Landscape Features,
2023
University of Nebraska-Lincoln
Habitat Heterogeneity In Nebraska Streams And Distribution Prediction For Tier-1 Cyprinids Using Multi-Scale Modeling Of Fluvial And Landscape Features, Connor P. Hart
School of Natural Resources: Dissertations, Theses, and Student Research
Multiscale environmental processes determine in-stream habitat conditions which drive species distributions. Habitat constitutes the physical template upon which ecological processes occur and species conduct life stage activities. Habitat heterogeneity promotes biodiversity of aquatic systems. Stream classification informs freshwater conservation by providing a useful framework to account for habitat heterogeneity, often based on landscape regions of similar environmental processes. A greater understanding of landscape-based classification frameworks as means to classify stream systems may improve understanding of drivers of biodiversity. Using Nebraska as a case study, on a statewide scale, objectives were 1) to characterize habitat availability for several at-risk fish species, …
Interactions Between Sediment Mechanical Structure And Infaunal Community Structure Following Physical Disturbance,
2023
University of South Alabama
Interactions Between Sediment Mechanical Structure And Infaunal Community Structure Following Physical Disturbance, William Cyrus Roger Clemo
Theses and Dissertations
Shallow, river-influenced coastal sediments are important for global carbon storage and nutrient cycling and provide a habitat for diverse communities of invertebrates (infauna). Elevated bed shear stress from extreme storms can resuspend, transport, and deposit sediments, disrupting the cohesive structure of muds, and sorting and depositing sand eroded from beaches. These physical disruptions can also resuspend or smother infauna, decreasing abundances and changing community structure. Infaunal activities such as burrowing, tube construction, and feeding can impact sediment structure and stability. However, little is known about how physical disturbance impacts short and long-term sediment habitat suitability and whether disturbance-tolerant infauna influence …
Landscape/Atmosphere Interactions And Carbon-Dioxide Dynamics In The Great Onyx Groundwater Basin, Mammoth Cave National Park, Kentucky,
2023
Western Kentucky University
Landscape/Atmosphere Interactions And Carbon-Dioxide Dynamics In The Great Onyx Groundwater Basin, Mammoth Cave National Park, Kentucky, Meghan Raines
Masters Theses & Specialist Projects
An increase in atmospheric CO2 since the Industrial Revolution has altered rates of global climate change and has motivated a need to better quantify the flux of carbon between Earth’s reservoirs. Attempts to quantify the exchange of atmospheric carbon between sources and sinks have led to an increasing interest in the terrestrial landscape, including the continental carbon sink associated with carbonate-mineral dissolution. This research sought to better inform an understanding of karst landscapes and their relationship with global climate change through carbon cycling. The study utilized high-resolution data collection of pH, temperature, and specific conductance of waters in the Cascade …
Electrofacies Analysis Using A Geostatistical Approach, Northern Iraq Case Study,
2023
Department of Petroleum Geosciences, Faculty of Science, Soran University, Soran, Erbil, Iraq
Electrofacies Analysis Using A Geostatistical Approach, Northern Iraq Case Study, Hussein S. Hussein
Polytechnic Journal
The distribution of petrophysical parameters is governed by lithology, hence understanding the spatial variation in lithology is essential for reservoir characterisation. This study points out the use of well logs to estimate the lithology of carbonate rocks (limestone, marly limestone, dolomite, and dolomitic limestone) found in Upper Cretaceous to Miocene formations at the Khabbaz Oil Field in Northern Iraq. Applying the multivariate regression technique to neutron, and density data enabled accurate lithology prediction. By using independent values (well log data) to predict a dependent value (lithology), this technique is a progression of regression analysis. The formations under study comprised a …
Quantifying The Role Of Water Quality On Nitrogen Cycling In A Trophic Estuary,
2023
Kennesaw State University
Quantifying The Role Of Water Quality On Nitrogen Cycling In A Trophic Estuary, Kayla Gonzalez-Boy
Symposium of Student Scholars
Jobos Bay Estuary is an intertidal, tropical estuary located in southern Puerto Rico. The estuary covers about 12 km2 and has a variety of habitats, such as seagrass beds, mangroves, mud flats, and coral reefs, which play important roles in sediment trapping and water quality maintenance. Seagrasses also serve as nursery and feeding grounds and provide shelter for macrofauna. Currently, the role of seagrasses and water quality on nitrogen (N) cycling in trophic estuaries is not well constrained. Understanding variations in sediment-based effects on N cycling rates and transformations, and how they are associated with water quality, is an …
Beyond The Tide: A Comprehensive Guide To Sea-Level-Rise Inundation Mapping Using Foss4g,
2023
Florida International University
Beyond The Tide: A Comprehensive Guide To Sea-Level-Rise Inundation Mapping Using Foss4g, Levente Juhasz, Jinwen Xu, Randall W. Parkinson
GIS Center
No abstract provided.
Table Of Contents,
2023
China Coal Technology and Engineering Group (CCTEG)
Numerical Simulations Of Enhancing Permeability And Gas Extraction Of Thick Coal Seams Through Static Fracturing,
2023
College of Environment and Resources, Xiangtan University, Xiangtan 411105, China; Key Laboratory of Safety and High-efficiency Coal Mining, Ministry of Education (Anhui University of Science and Technology), Huainan 232001, China
Numerical Simulations Of Enhancing Permeability And Gas Extraction Of Thick Coal Seams Through Static Fracturing, Wang Xinfeng, Liu Wengang, Wang Long, Wei Youyu, Zhang Qiao
Coal Geology & Exploration
This study seeks to improve the underground operation efficiency and optimize the borehole arrangement parameters for static fracturing of coal seams. To this end, this study conducted tests in the belt roadway of the No. 12316 fully mechanized mining face in the Wangjialing Coal Mine, China Coal Huajin Group. By combining the equations for coal seams’ deformation and failure, gas diffusion and seepage, and coal seams’ permeability evolution, this study constructed a model of the damage and permeability evolution of coal seams. Based on the numerical simulations of the process of static fracturing and permeability enhancement of coals, as well …
Stress Field Of High-Temperature Wellbore Under Spray Cooling For Underground Coal Gasification,
2023
School of Mechanical Engineering, Southwest Petroleum University, Chengdu 610500, China; Energy Equipment Research Institute, Southwest Petroleum University, Chengdu 610500, China
Stress Field Of High-Temperature Wellbore Under Spray Cooling For Underground Coal Gasification, Tang Yang, Xie Na, Xiong Haoyu, He Yin, Huang Shunxiao
Coal Geology & Exploration
As a supplement to traditional physical coal mining technology, underground coal gasification (UCG) is a new generation of chemical coal mining technology. During the gasification, the wellbore of UCG production wells is subjected to the combined action of high temperature and internal pressure loads. Targeting the structural characteristics of the wellbore of UCG production wells, this study, based on the heat transfer theory, established a calculation model for the transient temperature of the wellbore under the cooling through annular spray water injection. By combining the wellbore pressure model, as well as the elasticity theory and the wall cylinder theory, this …
Genetic Type And Gas-Generating Potential Of Coalbed Methane In The Bayanhua Sag, Erlian Basin,
2023
Inner Mongolia Coal Exploration Unconventional Energy Co., Ltd., Hohhot 010010, China; Inner Mongolia Coal Exploration & New Energy Development Co., Ltd., Hohhot 010010, China
Genetic Type And Gas-Generating Potential Of Coalbed Methane In The Bayanhua Sag, Erlian Basin, Meng Qin, Li Ling, Li Jie, Tian Wenguang, Lin Haitao, Li Heng
Coal Geology & Exploration
The Bayanhua Sag in the Erlian Basin is a critical experimental area for coalbed methane (CBM) development from low-rank coals in Inner Mongolia. However, the relatively low exploration level and the limited understanding of the CBM origin in the sag restrict the CBM exploration and development to some extent. This study tested the gas components, stable isotopes and hydrochemistry of the gas and water samples from CBM wells in the Bayanhua Sag. It also conducted radioisotopic dating for these samples. By combining the classic charts for the identification of natural gas origin, this study clarified the gas origins, further analyzed …
A Simulation Study On The Suspension And Transport Patterns Of Proppants In Long Distance Pipelines For Integrated Well And Ground Fracturing,
2023
CCTEG China Coal Research Institute, Beijing 100013, China; CCTEG Xi’an Research Institute (Group) Co., Ltd., Xi’an 710077, China
A Simulation Study On The Suspension And Transport Patterns Of Proppants In Long Distance Pipelines For Integrated Well And Ground Fracturing, Li Haozhe, Jiang Zaibing, Sun Siqing, Zhu Chuanyong, Fan Yao, Guo Yong, Cheng Bin
Coal Geology & Exploration
Integrated well and ground fracturing is a developmental trend for the staged fracturing of underground long boreholes in coal mines. Using the integrated fracturing technology, the fracturing fluids, after being pressurized using a ground fracturing pump, enter long boreholes in underground coal mines through ground penetrating wells and long distance pipelines, aiming to achieve fracturing with high injection rates of fracturing fluids. The suspension and transport patterns of proppants in long distance pipelines hold critical significance for optimizing parameters related to proppant adding and avoiding sand plugging in pipelines. This study evaluated the rheological properties and proppant carrying capacity of …
Numerical Simulations Of The Effects Of Bedding Planes On Hydraulic Fracture Propagation Law In Oil Shale,
2023
College of Construction Engineering, Jilin University, Changchun 130026, China; National-Local Joint Engineering Laboratory of In-situ Conversion, Drilling and Exploitation Technology for Oil Shale, Changchun 130026, China; Provincial and Ministerial Co-construction of Collaborative Innovation Center for Shale Oil & Gas Exploration and Development, Changchun 130026, China; Key Lab of Ministry of Natural Resources for Drilling and Exploitation Technology in Complex Conditions, Changchun 130026, China
Numerical Simulations Of The Effects Of Bedding Planes On Hydraulic Fracture Propagation Law In Oil Shale, Li Yanwei, Zhu Chaofan, Zeng Yijian, Shui Haoche, Fan Cunhan, Guo Wei
Coal Geology & Exploration
Hydraulic fracturing serves as a major technical means for the exploitation of oil shale reservoirs presently, and the hydraulic fracture morphology in oil shales is primarily affected by differences in the characteristics of bedding planes. However, current studies mostly focus on the influence of the developmental degree of bedding planes on fracture propagation, overlooking the effects of the bedding plane thickness itself on hydraulic fracture propagation. This study delves into the oil shale in the Xunyi area, Ordos Basin. Based on the theory of linear elastic fracture mechanics, this study developed a stress-damage-seepage model of hydraulic fracture propagation. Using the …
Vertical Variability Of Hydrogeological Characteristics Of Luohe Formation By Double Packer System Pumping Test,
2023
CCTEG Xi’an Research Institute (Group) Co., Ltd., Xi’an 710077, China; Shaanxi Key Laboratory of Prevention and Control Technology for Coal Mine Water Hazard, Xi’an 710077, China
Vertical Variability Of Hydrogeological Characteristics Of Luohe Formation By Double Packer System Pumping Test, Li Chaofeng, Liu Yexian, Zhang Jinkui, Ren Dengjun, Hou Tao, Liu Zengping, Xu Xinqi, Ma Ji, Wang Qingzhen, Duan Xiliang, Xing Jiebo, Li Yang
Coal Geology & Exploration
To investigate the hydrogeological conditions of the thick Luohe Formation in Ordos Basin and quantitatively evaluate vertical variation characteristics of its aquifer’ s water-rich, proposes the method of using the coefficient of transmissibility to evaluate the water-rich of the aquifer, and give the seven level classification standard of water-rich by the method of determining coefficient of transmissibility. The double-packer system was used to carry out the pumping tests of 10 vertical sections of fixed thickness of the Luohe Formation in the DJ1 and DJ2 boreholes in the Gaojiabao mine field, shaanxi, and the hydrogeological parameters were calculated. Using the comprehensive …
Dynamic Prediction Method Of Tunnel Water Inflow Based On Detailed Depiction Of Complex Geological Bodies,
2023
Yellow River Engineering Consulting Co., Ltd., Zhengzhou 450003, China; Key Laboratory of Water Management and Water Security for Yellow River Basin, Ministry of Water Resources (Under Construction), Zhengzhou 450003, China; School of Water and Environment, Chang’an University, Xi’an 710054, China
Dynamic Prediction Method Of Tunnel Water Inflow Based On Detailed Depiction Of Complex Geological Bodies, Du Yajun, Li Qingbo, Wan Weifeng, Yang Fengwei, Li Yazhe, Qian Hui
Coal Geology & Exploration
It is a challenge to accurately characterize the irregular geological bodies and underground structures such as inclined faults and inclined tunnels during the numerical simulation of tunnel water inflow prediction, and the prediction generally assumes that the tunnel excavation is completed instantaneously without considering the construction progress. A dynamic prediction method for tunnel water inflow based on precise characterization of complex geometric bodies was proposed by addressing the non-self-intersection and watertight issues required in the coupling process of three-dimensional (3D) geological models and 3D groundwater numerical models. Specifically, a sealed boundary interface of inclined tunnels, shafts, inclined faults and irregular …
Characteristics And Genetic Mechanism Of Low Sulfate In High-Salt Groundwater Of Permian Sandstone In Fudong Mining Area, Huainan,
2023
School of Resources and Geosciences, China University of Mining and Technology, Xuzhou 221116, China; School of Resource and Environmental Engineering, Anhui University, Hefei 230601, China
Characteristics And Genetic Mechanism Of Low Sulfate In High-Salt Groundwater Of Permian Sandstone In Fudong Mining Area, Huainan, Jiang Chunlu, Huang Wendi, Fu Xianjie, Zheng Liugen, Cheng Shigui, Shan Chonglei
Coal Geology & Exploration
Hydrogeochemistry research of groundwater in coal mining areas is of great significance to the prevention and control of mine water and the comprehensive utilization of water resources. In terms of the low surfate of Permian sandstone water in Fudong mining area, Anhui Huainan Coalfield, the hydrochemical characteristics, water-rock interaction and low sulfate genesis of sandstone water were studied through water sampling and test by multivariate statistical method, in combination with the hydrogeological condition analysis and the sulfur and oxygen isotope technology. The results show that the Permian sandstone water in the study area is weakly alkaline, with an average TDS …
Evaluation Of Water Quality And Identification Of Pollution Factors In Mining Subsidence Area With High Phreatic Water Level,
2023
National Engineering Laboratory for Protection of Coal Mine Eco-Environment, Huainan 232001, China; Anhui Province Engineering Research Center of Coal Mining Green Low-Carbon Development, Huainan 232001, China
Evaluation Of Water Quality And Identification Of Pollution Factors In Mining Subsidence Area With High Phreatic Water Level, Hu Lin, Chen Yongchun, Xu Yanfei, Li Bing, Wang Jin, An Shikai, Chen Chen, Sun Hongjie, Miao Wei
Coal Geology & Exploration
Huainan mining area is characterized by a high phreatic water level, as well as a wide range and large area of coal mining subsidence areas, with the water quality monitoring data missing and prominent water environment. Therefore, the evaluation of water quality monitoring and identification of pollution factors in large subsidence area is of great significance to regional water environmental governance. Specifically, the water quality of the subsidence area was evaluated with the Nemerow pollution index method by testing the water samples collected from 175 sampling points in the study area. Meanwhile, the eutrophication state of water bodies was evaluated …
A Method For Evaluating Aquiclude Stability In The Water Conservation-Based Mining Of Shallowly Buried Coal Seams In Ecologically Vulnerable Areas In Northwest China,
2023
Institute of Resources and Earth Sciences, China University of Mining and Technology, Xuzhou 221116, China; Inner Mongolia Coal Exploration New Energy Development Co. LTD, Hohhot 010010, China
A Method For Evaluating Aquiclude Stability In The Water Conservation-Based Mining Of Shallowly Buried Coal Seams In Ecologically Vulnerable Areas In Northwest China, Li Heng, He Tao, Guo Bin
Coal Geology & Exploration
Water conservation and coal mining are both critical to Northwest China. Water conservation-based coal mining is an important technology for the coordinated development of coal and water resources in this region. In this technology, the evaluation of aquiclude stability is critical. Due to the shallow depth of coal seams, intense topographic cutting, and complex changes in near-surface aquifers in the ecologically vulnerable areas in Northwest China, there exist large errors between traditional methods for aquiclude evaluation and the actual hydrological observations in these areas. To address this challenge, this study develops using the 3D geological modelling combined with numerical simulation …
Micp Restoration Law Of Coal Mining Induced Ground Fissures And Its Influencing Factors,
2023
School of Mining and Mechanical Engineering, Liupanshui Normal University, Liupanshui 553004, China; College of Geology and Environment, Xi’an University of Science and Technology, Xi’an 710065, China; College of Resource and Environmental Engineering, Guizhou University, Guiyang 550025, China
Micp Restoration Law Of Coal Mining Induced Ground Fissures And Its Influencing Factors, Li Tao, Gao Ying, Yan Jingwang, Zhang Jiarui, Kou Guigui, Ma Tengfei, Mei Aoran
Coal Geology & Exploration
The coal mining induced ground fissures in the loess covered area of northwest China cause shallow groundwater resource leakage and soil instability. Therefore, the experimental study was conducted on Microbial Induced Carbonate Precipitation (MICP) restoration of coal mining induced ground fissures in the loess covered area. Specifically, the characteristics of mining induced ground fissures were observed and their development characteristics were revealed based on Ningtiaota Coal Mine in northern Shaanxi. The coal mining induced ground fissures in loess were classified with consideration to the observed mine pressure. Based on the classification and characteristics of coal mining induced ground fractures, the …
