Physical Sciences and Mathematics Commons^™

Fracture Propagation Mechanism In Directional Perforation And Hydraulic Fracturing Of Coal Seam Horizontal Wells, Pang Tao, Jiang Zaibing, Hui Jiangtao, Jia Bingyi

Coal Geology & Exploration

Horizontal well perforation and fracturing in complex coal-bearing strata are key to increasing coal seam permeability and enhancing gas extraction efficiency, with the formation structure and perforation location determining fracture propagation. Considering the characteristics of formation structure and perforation locations, a fracturing geological model is established. Based on the finite element method, a numerical model is constructed to study the effects of perforation location, formation conditions, and the difference between vertical stress and horizontal stress on fracture perforation. Engineering verification is conducted, and construction suggestions are proposed. Key findings are as follows: There are three scenarios for the perforation locations: …

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 …

Propagation Of Hydraulic Fractures In Thin Interbedded Tight Sandstones, Yang Fan, Mei Wenbo, Li Liang, Sun Zening, An Qi, Yang Qi, Lu Meiquan, Yang Ruiyue

Coal Geology & Exploration

Thin interbedded tight sandstone reservoirs are characterized by strong vertical heterogeneity due to the superimposed pattern of the deposited sandstones and mudstones. As a result, hydraulic fractures are difficult to propagate vertically to effectively connect the reservoirs. Given this, ascertaining the vertical propagation patterns of hydraulic fractures in thin interbeds is of great significance for the development of thin interbedded tight sandstones. With the thin interbedded tight sandstone reservoirs of the lower Shihezi Formation in the Linxing block, Ordos Basin as a case study, this study built the fracture propagation model of these sandstones. Accordingly, it analyzed the effects of …

An Experimental Study On Factors Controlling The Proppant Transport In Hydraulic Fractures Of Coal Reservoirs, Su Xianbo, Fan Jian, Wang Ran, Wang Lufei, Zhao Fengzhen, Wang Qian

Coal Geology & Exploration

Effectively propping open hydraulic fractures in coal reservoirs plays an important role in ensuring the efficient production of coalbed methane (CBM). This study investigated the effects of fracture morphology and the volume, injection rate, and properties of fracturing fluids on proppant transport in fractures through visualized experiments. The results are as follows: (1) Proppants showed a relatively homogeneous distribution in simple fractures with a constant aperture. In contrast, they form room-and-pillar props composed of proppant pillars and proppant-free rooms in local simple fractures with varying apertures and reticular fractures due to the effects of the varying flow rates of fracturing …

A New Model Of Surface And Underground Integrated Three-Dimensional Prevention And Control Of Rock Burst In Binchang Mining Area, Wu Xueming, Ma Xiaohui, Lyu Dazhao, Zheng Kaige, Wang Dongjie

Coal Geology & Exploration

With the continuous increase of coal mining intensity, the mine gradually moves to the deep, bringing about increasingly serious rock burst hazard. The deep rock burst mines often have one or more layers of hard and thick rock strata. These hard roofs are thick and strong integrity. When they suddenly rupture, they can release a large amount of elastic energies, which can easily to cause rock burst accidents and seriously restrict the safety of mine production. Herein, appropriate treatment measures were put forward for the special situation of deep burial depth of coal seam and general presence of many kinds …

Experimental Study Of Hydraulic Fracture Evolution With Materials Similar To The Structural Plane, Li Quangui, Wu Xiaobin, Hu Qianting, Liu Le, Shi Jialin, Song Mingyang

Coal Geology & Exploration

The structural plane extensively occurs in coal measures, and is one of the key factors affecting the hydraulic fracturing effect of coal/rock. The fabrication time and filling material types of the structural plane were adjusted to obtain the coal/rock specimens without the filling structural plane, or the coal/rock specimens with the filling structural plane. The physical experiment for hydraulic fracturing was carried out to find out the effect and action mechanism of the structural plane type and injected flow rate on hydraulic fracture extension. As indicated by the result, in the condition of the injected flow rate of 50 mL/min, …

Experimental Study On The Mechanical Properties Of Coal-Like Materials For Hydraulic Fracturing Simulation, Zhai Cheng, Zheng Yangfeng, Yu Xu, Xu Jizhao, Sun Yong, Cong Yuzhou, Tang Wei, Li Yujie, Zhu Xinyu, Chen Aikun

Coal Geology & Exploration

Simulation experiments on hydraulic fracturing of the coal seam in the laboratory are an effective method to study the mechanism of fracturing and enhancing permeability of coal-rock mass by hydraulic fracturing in coal mines. However, the technology in-situ sampling for large-size coal mass is immature, and the existing large-size coal samples are mostly taken from the stress-relaxation area, which can be further damaged in the transportation and preparation processes, causing large dispersion in test results. Therefore, The use of coal-like materials is a viable option to replace large-size raw coal for hydraulic fracturing simulation experiments. The mechanical properties of coal-like …

High-Efficiency Regional Gas Drainage Model After Hydraulic Fracturing Of Comb-Shaped Long Boreholes In The Roof Of Broken Soft And Low Permeability Coal Seam, Chen Dongdong, Wang Jianli, Jia Bingyi, Xi Jie

Coal Geology & Exploration

Advanced management of gas enrichment area is an important guarantee to realize safe, efficient and intelligent mining in coal mine. Aiming at the problem of high-efficiency gas drainage in broken and soft coal seam region, taking No.3 coal seam in Hancheng mining area as the research object, a gas drainage mode of comb-shaped long borehole hydraulic fracturing in the roof of coal seam is proposed. The applicability of the model is verified by means of theoretical analysis, numerical simulation and field test, and the fracture propagation law, gas drainage mechanism, and fracturing curve features of comb-shaped borehole in adjacent roof …

Mesoscopic Law Of Stress And Fracture Evolution Of Coal Seams Hydraulic Fracturing, Li Quangui, Deng Yize, Hu Qianting, Zhang Yuebing, Song Mingyang, Liu Jichuan, Shi Jialin

Coal Geology & Exploration

Hydraulic fracturing is a technology to increase coal seam permeability, and its stress evolution characteristics and the judgment of fracture morphology and propagation range are particularly important. In this paper, based on directional fracturing, a fluid-structure coupling model of hydraulic fracturing is established by using the discrete element numerical method. The effects of fracturing flow, Poisson’s ratio, natural fracture density on stress evolution and fracture evolution, and their mesoscopic laws are investigated by means of the stress path and crack hot spot diagram. The results show that the stress evolution direction and the final stress path curve shape are obviously …

Modeling Of Fluid Injection-Related Processes In Hydrocarbon Reservoirs In Alberta, Canada, Negar Nazari

Electronic Thesis and Dissertation Repository

In the last decade, with the development of horizontal drilling and multistage hydraulic fracturing technology, extraction of unconventional resources has significantly increased in western Canada. These industrial activities have been associated with the rise in the seismicity rate. This thesis aimed to improve the quality of the available geomechanical models of the injection-induced seismicity in the Western Canada Sedimentary Basin, by incorporating detailed geoscience characterization for two unconventional reservoirs of the Duvernay Formation in the Fox Creek area and the Cardium Formation in West Pembina. Hydraulic fracturing has induced seismicity in the first area, but no induced seismicity has been …

Evaluation Method And Application Of Fracturing Effect Based On Dynamic Permeability Change Of Coal Reservoir Hydraulic Fracturing, Shan Tuo, Sun Changyan, Wang Qian, Xie Xiangjun, Fan Yigang

Coal Geology & Exploration

The fracturing construction curve is considered to be an important basis for reflecting the fracturing effect, while the dynamic change of reservoir permeability in the fracturing stage can more intuitively reflect the effect of fracture formation. In this paper, a quantitative evaluation method for reservoir dynamic permeability in fracturing stage was established based on the principle of well testing. Then, the method was applied to evaluate the fracturing effect of two coalbed methane (CBM) wells in a block in southern Junggar Basin, and the dynamic permeability curve of reservoir during fracturing stage is obtained. Meanwhile, the G-function method was …

Application Of Advanced Regional Treatment Technology Of Hard Roof In Buertai Coal Mine Of Shendong Coal Group, Yang Junzhe, Wang Zhenrong, Lyu Qingxu, Yang Sen, Li Guo, Zheng Kaige

Coal Geology & Exploration

The hard roof is a difficult problem in rock stratum control. The breaking and instability of high hard rock strata often induces strong coal pressure disasters, seriously threatening the safety production in coal mines. Hard roof control is one of the major problems in coal mine safety production. In response to the problems of large thickness, high hardness of the coal seam roof and its difficulty in collapse in Buertai Coal Mine in Shendong Mining Area, the hydraulic fracturing mechanism and technical advantages of directional long borehole segmented hydraulic fracturing are analyzed. The location of boreholes is determined based on …

Medium Characteristics And Hydrodynamic Evolution Law Of High Salinity Mine Water Recharge In Deep Well, Liu Qi, Wang Weijun, Luo Bin, Wang Houzhu, Zhang Zhijun

Coal Geology & Exploration

The treatment and discharge of high salt mine water is one of the important factors affecting efficient coal mining in recent years. It is a worth exploring method to reduce the discharge of mine water by selecting the appropriate aquifer under the floor of the coal seam and transferring the high salt mine water to other places. Taking the X mine in the Ordos Basin as an example, the Baotashan sandstone and the deep Liujiagou Formation sandstone formation below the coal seam have transfer storage space. By mercury intrusion experiment and rock mechanics analysis, the two groups of formations were …

Shale Softening Based On Pore Network And Laboratory Investigations, Di Zhang

Dissertations

This dissertation consists of two major parts: Firstly, experimental investigation of four major shale softening mechanisms and quantifications of structural parameters. Secondly, numerical simulations of nano-scale flow behaviors using the previous experiments determined parameters based on modified pore network modeling.

Hydraulic fracturing is widely applied to economical gas production from shale reservoirs. Still, the gradual swelling of the clay micro/nano-pores due to retained fluid from hydraulic fracturing causes a gradual reduction of gas production. Four different gas-bearing shale samples are investigated to quantify the expected shale swelling due to hydraulic fracturing. These shale samples are subject to heated deionized (DI) …

Impacts Of Oil And Gas Wastes On Landfill Leachate, Sewage Treatment Plants, And The Environment, Lauren Badertscher

Electronic Theses and Dissertations

Between January 2011 and March 2021 oil and gas wells in Pennsylvania produced

305,637,795 barrels of liquid waste and 6,992,957 tons of solid waste with the majority from

Marcellus Shale unconventional wells. This waste is not considered hazardous and over 89% of

the solid waste generated by unconventional and conventional oil and gas extraction has been

disposed of in landfills over the past decade. This study examined trends in the quantity of waste

produced and methods of disposal. Landfills accepting this waste were identified and their

general method of leachate treatment, using onsite facilities or offsite at wastewater treatment

plants, …

Modeling Hydraulic Fracturing Initiation And Propagation In Porous Rock Formationsl, Chang Huang

LSU Doctoral Dissertations

Hydraulic fracturing has long been introduced to the oil and gas industry since the early nineteenth century for both reservoir characterization and reservoir stimulation. Despite the progress made in the last two decades, many challenges still have not been tackled regarding not only the propagation problem but also the initiation problem due to its complexity. The dissertation is divided into two stages, i.e., before and after fracture initiation. The first stage of the research aimed at improving the accuracy in solving the poro-mechanical response of wellbore during fluid injection before a tensile fracture occurs, which is crucial to determine the …

Repetitive Sampling And Control Threshold Improve 16s Rrna Gene Sequencing Results From Produced Waters Associated With Hydraulically Fractured Shale, Jenna L. Shelton, Elliott P. Barnhart, Leslie Ruppert, Aaron M. Jubb, Madalyn S. Blondes, Christina A. Devera

United States Geological Survey: Staff Publications

Sequencing microbial DNA from deep subsurface environments is complicated by a number of issues ranging from contamination to non-reproducible results. Many samples obtained from these environments – which are of great interest due to the potential to stimulate microbial methane generation – contain low biomass. Therefore, samples from these environments are difficult to study as sequencing results can be easily impacted by contamination. In this case, the low amount of sample biomass may be effectively swamped by the contaminating DNA and generate misleading results. Additionally, performing field work in these environments can be difficult, as researchers generally have limited access …

Application Of Borehole Transient Electromagnetic Detection In The Test Of Hydraulic Fracturing Effect, Zhao Rui, Fan Tao, Li Yuteng, Wang Jikuang, Ma Yuan, Wang Bingchun, Liu Lei, Fang Zhe

Coal Geology & Exploration

Hydraulic fracturing technology is widely used in various aspects such as mine rock burst prevention and surrounding rock depressurization, but there has been a lack of efficient and intuitive technology for evaluating the fracturing effectiveness. To solve this problem, a three-component borehole TEM detection method using dynamic source and reception unit was proposed, and detection equipment and supporting construction techniques suitable for construction in hydraulic fracturing holes were developed. Two engineering tests have been carried out in a coal mine. By comparing the processing results of the vertical components of the two detection data before and after fracturing, a pure …

Stress-State And Injection-Rate Dependent Damage Processes During The Hydraulic Fracturing Of Granite, Gayani Sasendrika Gunarathna

Dissertations

Hydraulic fracturing is a well-stimulation technique that is employed in field applications, such as enhanced geothermal systems (EGS) and shale oil/gas extraction. This research experimentally investigates the effect of the state of stress and injection rate on the hydraulic fracturing processes. In addition, a displacement discontinuity method (DDM) code, FROCK, is used to model the crack initiation and propagation in a granite specimen under hydraulic fracturing conditions. In order to conduct the experimental work, a test setup capable of applying a triaxial state of stress and water pressure inside pre-fabricated flaws cut in prismatic granite specimens is developed. Additionally, the …

Household Water Security: An Analysis Of Water Affect In The Context Of Hydraulic Fracturing In West Virginia, Appalachia, Bethani Turley, Martina Angela Caretta

Faculty & Staff Scholarship

Hydraulic fracturing has been booming in the last decade in the United States. While natural gas extraction and production has improved the national energy security, it has raised questions around the water security of those communities where extraction is taking place. Both scientists and residents are concerned about hydraulic fracturing’s impacts on surface- and groundwater, especially regarding how hydraulic fracturing impacts residents’ access to safe household well water. In the past decade, the Marcellus Shale has been developed in Northwestern West Virginia, yet the human geography dimensions of oil and gas extraction in West Virginia remain to be investigated. This …

The Cognition Of Controversy: Examining Policy Elites’ Narrative Cognition And Communication Around Hydraulic Fracturing Practices In The U.S., Rachael M. Moyer

Graduate Theses and Dissertations

The use of hydraulic fracturing (HF) technologies to extract oil and gas in the United States has sparked contentious policy debates, producing inconsistent and inefficient policies that have done little to address the impacts of HF in any comprehensive way. Debates are accompanied by competing policy narratives that position HF as either an environmental threat or an economic opportunity, but little is known about how policy narratives around HF are used by individuals. This dissertation systematically examines how individuals cognitively internalize elements of competing HF policy narratives. Organized into three empirical chapters, this dissertation analyzes narrative cognition (Jones, Shanahan, and …

Investigation Of Energy-Related Wastewater Impacts On Disinfection By-Product Formation In Drinking Water, Hannah K. Liberatore

Theses and Dissertations

Elevated bromide and iodide in drinking water sources contribute to the formation of toxic brominated and iodinated disinfection by-products (DBPs) during drinking water treatment. Energy extraction and utilization processes, including hydraulic fracturing (HF) and coal-fired power plants (CFPPs), produce wastewaters with bromide/iodide levels on the order of tens to thousands of mg/L. These wastes have the potential to impact drinking water sources through both intentional (e.g., direct discharge) and accidental (e.g., basin overflow, spill) release pathways. This research focuses on a combination of quantitative and non-targeted approaches to assess DBP formation impacts from HF and CFPP wastewaters, with complementary toxicity …

Productivity Prediction Of Hypotonic Cbm Test Well In Jiaozuo Mining Area Under Hydraulic Fracturing, Wang Zhirong, Yang Jie, Chen Lingxia, Guo Zhiwei

Coal Geology & Exploration

In order to explore the permeable mechanism and the output law after fracturing of CBM in the "three soft" coal seam(soft coal, soft roof and soft bottom) of Jiaozuo under hydraulic fracturing, Based on the permeable model of reservoir fracture, considering the influence of fracture porosity on permeability after fracturing, a reservoir fracture penetration model was established, the application and analysis of the test well was carried out to obtain the characteristics of pressure cracks such as length, width, permeability and reservoir parameters after fracturing. Through the comprehensive analysis of isothermal adsorption curves and historical fitting, the recovery rate of …

Shale Play: Poems And Photographs From The Fracking Fields By Julia Spicher Kasdorf And Steven Rubin, Kelly Shepherd

The Goose

Review of Julia Spicher Kasdorf and Steven Rubin's Shale Play: Poems and Photographs from the Fracking Fields

Water Quality Assessment Of Deer Lakes County Park Before, During And After Unconventional Shale Gas Drilling, Daniel Robinson

Electronic Theses and Dissertations

Allegheny County, Pennsylvania, signed a lease to allow unconventional natural gas extraction from Marcellus Shale beneath Deer Lakes County Park in 2014. The park has three man-made lakes and four waterways that eventually flow into the Allegheny River. Drilling commenced in early 2016, and there are now five producing wells. The park has an extensive abandoned coal mine network and several abandoned oil and gas wells. Thus, an independent water quality study was undertaken beginning in July 2015. Samples from seven different sites in the park were used to establish a water quality baseline prior to the drilling. Monthly sampling …

Seismic Monitoring And Baseline Microseismicity In The Rome Trough, Eastern Kentucky, N. Seth Carpenter, Andrew S. Holcomb, Zhenming Wang, John B. Hickman, Edward W. Woolery

Report of Investigations--KGS

In the central and eastern United States, felt earthquakes likely triggered by fluid injection from oil and gas production or wastewater disposal have dramatically increased in frequency since the onset of the unconventional shale gas and oil boom. In the Rome Trough of eastern Kentucky, fracture stimulations and wastewater injection are ongoing and occur near areas of historical seismic activity. Unlike in surrounding and nearby states (Ohio, West Virginia, and Arkansas), in Kentucky, no seismic events related to subsurface fluid injections have been reported as felt or detected by regional seismic networks, including the Kentucky Seismic and Strong-Motion Network.

Oil …

Petrophysical And Geomechanical Characterization Of The Marcellus Shale In The Appalachian Basin, Yixuan Zhu

Graduate Theses, Dissertations, and Problem Reports

In recent years, more and more attention is paid to shale gas and hydrocarbon liquids exploration and exploitation in unconventional reservoirs. With the development of horizontal drilling and hydraulic fracturing, production from unconventional reservoirs has been greatly increased. However, not all wells, regions and basins harbor highly successful shale gas and liquids producers. In order to improve the production efficiency and reduce the cost of projects, detailed analysis needs to be undertaken to characterize the reservoir. As opposed to conventional reservoirs, extraction of gas in the unconventional reservoir is dependent not only on the reservoir quality, but also on completion …

Geomechanical Modelling Of Induced Seismicity, Bodi Zhao

Electronic Thesis and Dissertation Repository

In recent years, there has been a dramatic increase in seismicity (earthquakes) due to anthropogenic activities related to the unconventional oil and gas exploration in the Western Canada Sedimentary Basin (WCSB) and the central U.S. There are compelling evidences that hydraulic fracturing and wastewater injection operations in those areas play a key role in induced seismicity. To better understand the physical mechanisms involved, this thesis aims to explore the mechanisms responsible for occurrence of induced earthquakes: mainshock-aftershock triggering mechanism and poroelastic response. In the first approach, the obtained results indicate the relationship between the Coulomb stress changes after 4 moderate …

“Either Secrecy, Or Legal Monopoly”: Why We Should Choose Fracking Patents, Sarah Spencer

William & Mary Environmental Law and Policy Review

No abstract provided.

Estimating The Creation And Removal Date Of Fracking Ponds Using Trend Analysis Of Landsat Imagery, Rutherford V. Platt, David Manthos, John Amos

Environmental Studies Faculty Publications

Hydraulic fracturing, or fracking, is a process of introducing liquid at high pressure to create fractures in shale rock formations, thus releasing natural gas. Flowback and produced water from fracking operations is typically stored in temporary open-air earthen impoundments, or frack ponds. Unfortunately, in the United States there is no public record of the location of impoundments, or the dates that impoundments are created or removed. In this study we use a dataset of drilling-related impoundments in Pennsylvania identified through the FrackFinder project led by SkyTruth, an environmental non-profit. For each impoundment location, we compiled all low cloud Landsat imagery …