Download or read book Appraisal of Transport and Deformation in Shale Reservoirs Using Natural Noble Gas Tracers written by and published by . This book was released on 2015 with total page 74 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report presents efforts to develop the use of in situ naturally-occurring noble gas tracers to evaluate transport mechanisms and deformation in shale hydrocarbon reservoirs. Noble gases are promising as shale reservoir diagnostic tools due to their sensitivity of transport to: shale pore structure; phase partitioning between groundwater, liquid, and gaseous hydrocarbons; and deformation from hydraulic fracturing. Approximately 1.5-year time-series of wellhead fluid samples were collected from two hydraulically-fractured wells. The noble gas compositions and isotopes suggest a strong signature of atmospheric contribution to the noble gases that mix with deep, old reservoir fluids. Complex mixing and transport of fracturing fluid and reservoir fluids occurs during production. Real-time laboratory measurements were performed on triaxially-deforming shale samples to link deformation behavior, transport, and gas tracer signatures. Finally, we present improved methods for production forecasts that borrow statistical strength from production data of nearby wells to reduce uncertainty in the forecasts.
Download or read book Noble Gas Tracing of Fluid Transport in Shale Reservoirs written by and published by . This book was released on 2014 with total page 1 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Evaluation of Subsurface Fluid Migration Using Noble Gas Tracers and Numerical Modeling written by William Karl Eymold and published by . This book was released on 2020 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Fluid flow in the subsurface is a complex phenomenon, significantly affected by geologic characteristics such as porosity and permeability, temperature, compaction, sedimentation, and tectonic processes. The upper crust is often faulted and fractured, and these structural features will alter the inherent geophysical properties of the formations in which they are contained. Because individual techniques used to evaluate crustal fluids, paleo-temperature conditions of formations, and migration pathways each have their own limitations, multidisciplinary approaches must be developed to infer geologic history and past events of fluid flow accurately. In order to interrogate migration pathways and sources of crustal fluids, noble gases have been used to identify mechanisms of fluid flow, hydrocarbon origin, and constrain the temperature conditions of physical processes and chemical reactions. The inert nature and well-constrained sources of noble gases allows them to retain information about geologic history of fluids and rocks over time. Specific isotopic signatures and changes to ratios can distinguish styles of mixing or deformation that occurs during the development of sedimentary basins and orogenic fluid flow. Here, samples collected from the Karoo Basin in South Africa provide an opportunity to analyze the geochemistry of groundwater prior to petroleum exploration. In the Karoo Basin, a field study of the water geochemistry of groundwaters collected before industrial activity showed that naturally-occurring methane was present in the majority of samples and was associated with high salinity and high concentrations of crustal noble gases. The presence of atmospheric noble gases in these samples also suggests fractionation as the natural gas migrated from its source and was emplaced in shallow aquifers. Areas with higher intensity of faulting and fracturing in the Karoo served as preferential pathways during this fluid migration and may still operate that way at present. The effects of faults on fluid flow are further studied in this work by assessing the noble gas distributions along the damage zone of a thrust fault in the Northern Appalachian Basin in New York. Near the fault plane, the 4He concentrations display ~90% loss of the amount predicted and measured in samples further from the fault. The noble gas distribution supports previous fault assessments determined by calculations based on the geometry of the fault core, damage zone, and displacement and suggests that this fault served as a conduit during multiple episodes of fluid flow in the past. Numerical simulations are also beneficial to determine the rates of fluid migration over time and predict advection and diffusion of subsurface fluids based on observed data. By calculating diffusive loss of 4He from quartz grains, predictions can be made regarding the temperature history and permeability of the fault and local system. The formation of gas hydrates in porous sediments beneath the seafloor requires methanogenesis of organic matter and migration of natural gas into appropriate depths where pressure and temperature conditions lead to stability. Calculations based on noble gas observations along the fault damage zone can be used to evaluate retention or release of noble gases in crustal rock and simulations of methane production and migration processes based on input parameters from real world data can be used to predict the occurrence of gas hydrate in Blake Ridge using the flow and transport simulator, PFLOTRAN. By combining field, laboratory, and computational approaches, the results from these interdisciplinary studies offer greater understanding of subsurface flow and can be used to emplace more realistic constraints on geologic inferences.
Download or read book Geomechanical Studies of the Barnett Shale Texas USA written by John Peter Vermylen and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis presents five studies of a gas shale reservoir using diverse methodologies to investigate geomechanical and transport properties that are important across the full reservoir lifecycle. Using the Barnett shale as a case study, we investigated adsorption, permeability, geomechanics, microseismicity, and stress evolution in two different study areas. The main goals of this thesis can be divided into two parts: first, to investigate how flow properties evolve with changes in stress and gas species, and second, to understand how the interactions between stress, fractures, and microseismicity control the creation of a permeable reservoir volume during hydraulic fracturing. In Chapter 2, we present results from adsorption and permeability experiments conducted on Barnett shale rock samples. We found Langmuir-type adsorption of CH4 and N2 at magnitudes consistent with previous studies of the Barnett shale. Three of our samples demonstrated BET-type adsorption of CO2, in contrast to all previous studies on CO2 adsorption in gas shales, which found Langmuir-adsorption. At low pressures (600 psi), we found preferential adsorption of CO2 over CH4 ranging from 3.6x to 5.5x. While our measurements were conducted at low pressures (up to 1500 psi), when our model fits are extrapolated to reservoir pressures they reach similar adsorption magnitudes as have been found in previous studies. At these high reservoir pressures, the very large preferential adsorption of CO2 over CH4 (up to 5-10x) suggests a significant potential for CO2 storage in gas shales like the Barnett if practical problems of injectivity and matrix transport can be overcome. We successfully measured permeability versus effective stress on two intact Barnett shale samples. We measured permeability effective stress coefficients less than 1 on both samples, invalidating our hypothesis that there might be throughgoing flow paths within the soft, porous organic kerogen that would lead the permeability effective stress coefficient to be greater than 1. The results suggest that microcracks are likely the dominant flow paths at these scales. In Chapter 3, we present integrated geological, geophysical, and geomechanical data in order to characterize the rock properties in our Barnett shale study area and to model the stress state in the reservoir before hydraulic fracturing occurred. Five parallel, horizontal wells were drilled in the study area and then fractured using three different techniques. We used the well logs from a vertical pilot well and a horizontal well to constrain the stress state in the reservoir. While there was some variation along the length of the well, we were able to determine a best fit stress state of Pp = 0.48 psi/ft, Sv = 1.1 psi/ft, SHmax = 0.73 psi/ft, and Shmin = 0.68 psi/ft. Applying this stress state to the mapped natural fractures indicates that there is significant potential for induced shear slip on natural fracture planes in this region of the Barnett, particularly close to the main hydraulic fracture where the pore pressure increase during hydraulic fracturing is likely to be very high. In Chapter 4, we present new techniques to quantify the robustness of hydraulic fracturing in gas shale reservoirs. The case study we analyzed involves five parallel horizontal wells in the Barnett shale with 51 frac stages. To investigate the numbers, sizes, and types of microearthquakes initiated during each frac stage, we created Gutenberg-Richter-type magnitude distribution plots to see if the size of events follows the characteristic scaling relationship found in natural earthquakes. We found that slickwater fracturing does generate a log-linear distribution of microearthquakes, but that it creates proportionally more small events than natural earthquake sources. Finding considerable variability in the generation of microearthquakes, we used the magnitude analysis as a proxy for the "robustness" of the stimulation of a given stage. We found that the conventionally fractured well and the two alternately fractured wells ("zipperfracs") were more effective than the simultaneously fractured wells ("simulfracs") in generating microearthquakes. We also found that the later stages of fracturing a given well were more successful in generating microearthquakes than the early stages. In Chapter 5, we present estimates of stress evolution in our study reservoir through analysis of the instantaneous shut-in pressure (ISIP) at the end of each stage. The ISIP increased stage by stage for all wells, but the simulfrac wells showed the greatest increase and the zipperfrac wells the least. We modeled the stress increase in the reservoir with a simple sequence of 2-D cracks along the length of the well. When using a spacing of one crack per stage, the modeled stress increase was nearly identical to the measured stress increase in the zipperfrac wells. When using three cracks per stage, the modeled final stage stress magnitude matched the measured final stage stress magnitude from the simulfrac wells, but the rate of stress increase in the simulfrac wells was much more gradual than the model predicted. To further investigate the causes of these ISIP trends, we began numerical flow and stress analysis to more realistically model the processes in the reservoir. One of our hypotheses was that the shorter total time needed to complete all the stages of the simulfrac wells was the cause of the greater ISIP increase compared to the zipperfrac wells. The microseismic activity level measured in Chapter 4 also correlates with total length of injection, suggesting leak off into the reservoir encouraged shear failure. Numerical modeling using the coupled FEM and flow software GEOSIM was able to model some cumulative stress increase the reservoir, but the full trend was not replicated. Further work to model field observations of hydraulic fracturing will enhance our understanding of the impact that hydraulic fracturing and stress change have on fracture creation and permeability enhancement in gas shales.
Download or read book Multiscale Analysis of Mechanical and Transport Properties in Shale Gas Reservoirs written by Mohammad Hatami and published by . This book was released on 2021 with total page 127 pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation focuses on multiscale analysis in shale to improve understanding of mechanical and transport properties in shale gas reservoirs. Laboratory measurements of the effects of constant confining pressure (CCP), and constant effective stress (CES) on permeability were coupled with multiscale finite element simulations and the development of a comprehensive apparent permeability model to study the mechanical behavior of shale and transport mechanisms in shale. Predicting long-term production from gas shale reservoirs is a challenging task due to changes in effective stress and permeability during gas production. Unlike coal, the variation of sorbing gas permeability with pore pressure in shale does not always feature a biphasic trend under a constant confining pressure. The present contribution demonstrates that the biphasic dependence of permeability on pore pressure depends on a number of physical and geometrical factors, each with a distinct impact on gas permeability. This includes pore size, adsorption isotherm, and the variation of gas viscosity with pore pressure.
Download or read book Petroleum Abstracts written by and published by . This book was released on 1991 with total page 1512 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Petroleum Abstracts Literature and Patents written by and published by . This book was released on 1988 with total page 1656 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Geologic Analysis of Naturally Fractured Reservoirs written by Ronald Nelson and published by Elsevier. This book was released on 2001-08-24 with total page 353 pages. Available in PDF, EPUB and Kindle. Book excerpt: Geologists, engineers, and petrophysicists concerned with hydrocarbon production from naturally fractured reservoirs will find this book a valuable tool for obtaining pertinent rock data to evaluate reserves and optimize well location and performance. Nelson emphasizes geological, petrophysical, and rock mechanics to complement other studies of the subject that use well logging and classical engineering approaches. This well organized, updated edition contains a wealth of field and laboratory data, case histories, and practical advice. A great how-to-guide for anyone working with fractured or highly anisotropic reservoirs Provides real-life illustrations through case histories and field and laboratory data
Download or read book Environmental Tracers in Subsurface Hydrology written by Peter G. Cook and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 545 pages. Available in PDF, EPUB and Kindle. Book excerpt: Environmental Tracers in Subsurface Hydrology synthesizes the research of specialists into a comprehensive review of the application of environmental tracers to the study of soil water and groundwater flow. The book includes chapters which cover ionic tracers, noble gases, chlorofluorocarbons, tritium, chlorine-36, oxygen-18, deuterium, and isotopes of carbon, strontium, sulphur and nitrogen. Applications of the tracers include the estimation of vertical and horizontal groundwater velocities, groundwater recharge rates, inter-aquifer leakage and mixing processes, chemical processes and palaeohydrology. Practicing hydrologists, soil physicists and hydrology professors and students will find the book to be a valuable support in their work.
Download or read book Unconventional Oil and Gas Resources written by Usman Ahmed and published by CRC Press. This book was released on 2016-04-05 with total page 862 pages. Available in PDF, EPUB and Kindle. Book excerpt: As the shale revolution continues in North America, unconventional resource markets are emerging on every continent. In the next eight to ten years, more than 100,000 wells and one- to two-million hydraulic fracturing stages could be executed, resulting in close to one trillion dollars in industry spending. This growth has prompted professionals ex
Download or read book Publications of the Geological Survey written by Geological Survey (U.S.) and published by . This book was released on 1984 with total page 348 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Characterization Modeling Monitoring and Remediation of Fractured Rock written by National Academies of Sciences, Engineering, and Medicine and published by National Academies Press. This book was released on 2021-01-29 with total page 177 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fractured rock is the host or foundation for innumerable engineered structures related to energy, water, waste, and transportation. Characterizing, modeling, and monitoring fractured rock sites is critical to the functioning of those infrastructure, as well as to optimizing resource recovery and contaminant management. Characterization, Modeling, Monitoring, and Remediation of Fractured Rock examines the state of practice and state of art in the characterization of fractured rock and the chemical and biological processes related to subsurface contaminant fate and transport. This report examines new developments, knowledge, and approaches to engineering at fractured rock sites since the publication of the 1996 National Research Council report Rock Fractures and Fluid Flow: Contemporary Understanding and Fluid Flow. Fundamental understanding of the physical nature of fractured rock has changed little since 1996, but many new characterization tools have been developed, and there is now greater appreciation for the importance of chemical and biological processes that can occur in the fractured rock environment. The findings of Characterization, Modeling, Monitoring, and Remediation of Fractured Rock can be applied to all types of engineered infrastructure, but especially to engineered repositories for buried or stored waste and to fractured rock sites that have been contaminated as a result of past disposal or other practices. The recommendations of this report are intended to help the practitioner, researcher, and decision maker take a more interdisciplinary approach to engineering in the fractured rock environment. This report describes how existing tools-some only recently developed-can be used to increase the accuracy and reliability of engineering design and management given the interacting forces of nature. With an interdisciplinary approach, it is possible to conceptualize and model the fractured rock environment with acceptable levels of uncertainty and reliability, and to design systems that maximize remediation and long-term performance. Better scientific understanding could inform regulations, policies, and implementation guidelines related to infrastructure development and operations. The recommendations for research and applications to enhance practice of this book make it a valuable resource for students and practitioners in this field.
Download or read book Rock Fractures and Fluid Flow written by National Research Council and published by National Academies Press. This book was released on 1996-08-27 with total page 568 pages. Available in PDF, EPUB and Kindle. Book excerpt: Scientific understanding of fluid flow in rock fracturesâ€"a process underlying contemporary earth science problems from the search for petroleum to the controversy over nuclear waste storageâ€"has grown significantly in the past 20 years. This volume presents a comprehensive report on the state of the field, with an interdisciplinary viewpoint, case studies of fracture sites, illustrations, conclusions, and research recommendations. The book addresses these questions: How can fractures that are significant hydraulic conductors be identified, located, and characterized? How do flow and transport occur in fracture systems? How can changes in fracture systems be predicted and controlled? Among other topics, the committee provides a geomechanical understanding of fracture formation, reviews methods for detecting subsurface fractures, and looks at the use of hydraulic and tracer tests to investigate fluid flow. The volume examines the state of conceptual and mathematical modeling, and it provides a useful framework for understanding the complexity of fracture changes that occur during fluid pumping and other engineering practices. With a practical and multidisciplinary outlook, this volume will be welcomed by geologists, petroleum geologists, geoengineers, geophysicists, hydrologists, researchers, educators and students in these fields, and public officials involved in geological projects.
Download or read book Geophysics and Geosequestration written by Thomas L. Davis and published by Cambridge University Press. This book was released on 2019-05-09 with total page 391 pages. Available in PDF, EPUB and Kindle. Book excerpt: An overview of the geophysical techniques and analysis methods for monitoring subsurface carbon dioxide storage for researchers and industry practitioners.
Download or read book An Independent Scientific Assessment of Well Stimulation in California written by Ccst and published by . This book was released on 2015-01-01 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Relative Permeability Of Petroleum Reservoirs written by M.M. Honarpour and published by CRC Press. This book was released on 2018-01-18 with total page 243 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book enables petroleum reservoir engineers to predict the flow of fluids within a hydrocarbon deposit. Laboratory techniques are described for both steady-state and unsteady state measurements, and the calculation of relative permeability from field data is illustrated. A discussion of techniques for determing wettability is included, along with theoretical and empirical methods for the calculation of relative permeability, and prediction techniques. Contents include: Measurement of Rock Relative Permeability; Two-Phase Relative Permeability; Factors Affecting Two-Phase Relative Permeability; Three-Phase Relative Permeability; and Index.
Download or read book Monitored Natural Attenuation of Inorganic Contaminants in Ground Water written by and published by . This book was released on 2007 with total page 124 pages. Available in PDF, EPUB and Kindle. Book excerpt: V.3 ... consists of individual chapters that describe 1) the conceptual background for radionuclides, including tritium, radon, strontium, technetium, uranium, iodine, radium, thorium, cesium, plutonium-americium and 2) data requirements to be met during site characterization.