Download or read book Investigation of Induced Microseismicity in Hydraulically Fractured Gas Wells written by J. E. Fix and published by . This book was released on 1992 with total page 128 pages. Available in PDF, EPUB and Kindle. Book excerpt: The results of the research in microseismic methods to determine hydraulic fracture dimensions during this contract were significant. Fracture diagnostics were monitored at the SFE no. 4 and two GRI cooperative wells. One of these wells further confirmed the viability of fracture diagnostics in previously fractured wells. A preliminary study was made with synthetic seismograms of crack waves calculated for an infinite fracture. Results are encouraging and suggest a sensitivity to fracture width. The theory needs to be expanded to include a finite fracture. The GRI Hydraulic Fracture Test Site (HFTS) development planning was a major effort. Teledyne Geotech (TG) personnel attended meetings of the Planning Team, Technical Review Committee (TRC), Diagnostics R & D Team, and several Working Groups. TG and S.A. Holditch and Assoc. wrote a Preliminary Development Plan describing the facilities and capabilities of the test site. The plan was presented in detail to the TRC and Project Advisors' Group (PAG). A comprehensive design was developed for the monitoring, acquisition, and data processing systems. The Diagnostics R & D Team designed a set of experiments to answer questions and issues concerned with fracture geometry mapping. A prototype geophone/cable assembly was obtained for the Data Well 1 at the Ft. Worth Basin candidate site. Teledyne Geotech aided GRI in presenting the hydraulic fracture diagnostics techniques to three candidate Field Test partners. No agreements were completed despite many contacts.

Download or read book Induced Seismicity Potential in Energy Technologies written by National Research Council and published by National Academies Press. This book was released on 2013-08-14 with total page 238 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the past several years, some energy technologies that inject or extract fluid from the Earth, such as oil and gas development and geothermal energy development, have been found or suspected to cause seismic events, drawing heightened public attention. Although only a very small fraction of injection and extraction activities among the hundreds of thousands of energy development sites in the United States have induced seismicity at levels noticeable to the public, understanding the potential for inducing felt seismic events and for limiting their occurrence and impacts is desirable for state and federal agencies, industry, and the public at large. To better understand, limit, and respond to induced seismic events, work is needed to build robust prediction models, to assess potential hazards, and to help relevant agencies coordinate to address them. Induced Seismicity Potential in Energy Technologies identifies gaps in knowledge and research needed to advance the understanding of induced seismicity; identify gaps in induced seismic hazard assessment methodologies and the research to close those gaps; and assess options for steps toward best practices with regard to energy development and induced seismicity potential.

Download or read book Microseismic Imaging of Hydraulic Fracturing written by Shawn Mawell and published by SEG Books. This book was released on 2014-01-01 with total page 212 pages. Available in PDF, EPUB and Kindle. Book excerpt: Microseismic Imaging of Hydraulic Fracturing: Improved Engineering of Unconventional Shale Reservoirs (SEG Distinguished Instructor Series No. 17) covers the use of microseismic data to enhance engineering design of hydraulic fracturing and well completion. The book, which accompanies the 2014 SEG Distinguished Instructor Short Course, describes the design, acquisition, processing, and interpretation of an effective microseismic project. The text includes a tutorial of the basics of hydraulic fracturing, including the geologic and geomechanical factors that control fracture growth. In addition to practical issues associated with collecting and interpreting microseismic data, potential pitfalls and quality-control steps are discussed. Actual case studies are used to demonstrate engineering benefits and improved production through the use of microseismic monitoring. Providing a practical user guide for survey design, quality control, interpretation, and application of microseismic hydraulic fracture monitoring, this book will be of interest to geoscientists and engineers involved in development of unconventional reservoirs.

Download or read book Microseismic Monitoring written by Vladimir Grechka and published by SEG Books. This book was released on 2017-09-01 with total page 471 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the past decade, microseismic monitoring, a technology developed for evaluating completions of wells drilled to produce hydrocarbons from unconventional reservoirs, has grown increasingly popular among oil and gas companies. Microseismic Monitoring, by Vladimir Grechka and Werner M. Heigl, discusses how to process microseismic data, what can and cannot be inferred from such data, and to what level of certainty this might be possible. The narrative of the book follows the passage of seismic waves: from a source triggered by hydraulic fracture stimulation, through hydrocarbon-bearing formations, towards motion sensors. The waves’ characteristics encode the location of their source and its focal mechanism. The analysis of various approaches to harvesting the source-related information from microseismic records has singled out the accuracy of the velocity model, fully accounting for the strong elastic anisotropy of hydraulically fractured shales, as the most critical ingredient for obtaining precise source locations and interpretable moment tensors. The ray theory complemented by its modern extensions, paraxial and Fréchet ray tracing, provides the only practical means available today for building such models. The book is written for geophysicists interested in learning and applying advanced microseismic data-processing techniques.

Download or read book Unconventional Reservoir Geomechanics written by Mark D. Zoback and published by Cambridge University Press. This book was released on 2019-05-16 with total page 495 pages. Available in PDF, EPUB and Kindle. Book excerpt: A comprehensive overview of the key geologic, geomechanical and engineering principles that govern the development of unconventional oil and gas reservoirs. Covering hydrocarbon-bearing formations, horizontal drilling, reservoir seismology and environmental impacts, this is an invaluable resource for geologists, geophysicists and reservoir engineers.

Download or read book A Comparison of Microseismicity Induced by Gel proppant and Water injected Hydraulic Fractures Carthage Cotton Valley Gas Field East Texas written by and published by . This book was released on 2002 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt: In May and July, 1997, a consortia of operators and service companies conducted a series of hydraulic fracture imaging tests in the Carthage Cotton Valley gas field of East Texas (Walker, 1997). Microseismic data were collected and processed for six hydraulic fracture treatments in two wells (3 completion intervals per well) (Mayerhofer et al., 2000). One well was completed with gel-proppant treatments in which a viscous crosslink gel was injected to entrain high concentrations of sand proppant into formation. The second well was completed using treated water and very low proppant concentrations (waterfracs). Waterfracs have been shown to be just as effective as the conventional gel-proppant treatments in Cotton Valley reservoirs, but at greatly reduced cost. Mayerhofer and Meehan (1998) suggest two possible reasons why waterfracs are successful: (1) Induced shear displacement along natural and hydraulic fractures results in self-propping (shear dilation enhanced by fracture branching, proppant and spalled rock fragments), and (2) Fracture extension and cleanup is easier to achieve with low-viscosity fluids. With improved source location precision and focal mechanism determination (fracture plane orientation and sense of slip), we have reexamined the Cotton Valley data, comparing the seismicity induced by water and gel-proppant treatments at common depth intervals. We have improved the location precision and computed focal mechanism of microearthquakes induced during a series of hydraulic fracture completions within the Cotton Valley formation of East Texas. Conventional gel-proppant treatments and treatments using treated water and very low proppant concentrations (waterfracs) were monitored. Waterfracs have been shown to be just as effective as the conventional gel-proppant treatments in Cotton Valley reservoirs, but at greatly reduced cost (Mayerhofer and Meehan, 1998). Comparison of the seismicity induced by the two treatment types show similar distributions of event locations and focal mechanisms for common depth intervals. We interpret the induced seismicity to be primarily controlled by the natural fracture geometry and independent of treatment design. By implication, we expect the effectiveness of shear-induced fracture propping to be independent of the treatment fluid in Cotton Valley reservoirs.

Download or read book Human induced Earthquakes from Deep well Injection written by Congressional Research Service and published by . This book was released on 2015-01-08 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt: The development of unconventional oil and natural gas resources using horizontal drilling and hydraulic fracturing (fracking) has created new demand for wastewater disposal wells that inject waste fluids into deep geologic strata. An increasing concern in the United States is that injection of these fluids may be responsible for increasing rates of seismic activity. The number of earthquakes of magnitude 3.0 or greater in the central and eastern United States has increased dramatically since about 2009, from an average of approximately 20 per year between 1970 and 2000 to over 100 per year in the period 2010-2013. Some of these earthquakes may be felt at the surface. For example, 20 earthquakes of magnitudes 4.0 to 4.8 have struck central Oklahoma since 2009. The largest earthquake in Oklahoma history (magnitude 5.6) occurred on November 5, 2011, near Prague, causing damage to several structures nearby. Central and northern Oklahoma were seismically active regions before the recent increase in the volume of waste fluid injection through deep wells. However, the recent earthquake swarm does not seem to be due to typical, random, changes in the rate of seismicity, according to the U.S. Geological Survey. The relationship between earthquake activity and the timing of injection, the amount and rate of fluid injected, and other factors are still uncertain and are current research topics. Despite increasing evidence linking some deep-well disposal activities with human-induced earthquakes, only a small fraction of the more than 30,000 U.S. wastewater disposal wells appears to be associated with damaging earthquakes. The potential for damaging earthquakes caused by hydraulic fracturing itself, as opposed to deep-well injection of wastewater from oil and gas activities, appears to be much smaller. Hydraulic fracturing intentionally creates fractures in rocks, and induces microseismicity, mostly of less than magnitude 1.0, too small to feel or cause damage. In a few cases, however, fracking has led directly to earthquakes larger than magnitude 2.0, including at sites in Oklahoma, Ohio, England, and Canada. The Environmental Protection Agency's (EPA's) Underground Injection Control (UIC) program under the Safe Drinking Water Act (SDWA) regulates the subsurface injection of fluids to prevent endangerment of drinking water sources. EPA has established regulations for six classes of injection wells, including Class II wells used for the injection of fluids for enhanced oil and gas recovery and wastewater disposal. Most oil and gas states administer the UIC Class II program. The SDWA does not address seismicity, although EPA regulations for certain classes of injection wells require some evaluation of seismic risk. Such requirements do not apply to Class II wells; however, EPA has developed a framework for evaluating seismic risk when reviewing Class II permit applications in states where EPA administers this program. How Congress shapes EPA or other agency efforts to address and possibly mitigate human-caused earthquakes may be an issue in the 114th Congress. In 2011, in response to seismic events in Arkansas and Texas thought to be associated with wastewater disposal wells, EPA authorized a national UIC technical work group to develop recommendations to address the risk of Class II disposal-induced seismicity. EPA plans to issue a document outlining technical recommendations and best practices in early 2015. At the state level, several states have increased oversight of Class II wells in response to induced seismicity concerns. In 2014, state oil and gas and groundwater protection agencies established a work group to discuss Class II disposal wells and recent seismic events occurring in multiple states.

Download or read book Understanding Downhole Microseismic Data Analysis written by Jubran Akram and published by Springer Nature. This book was released on 2020-01-01 with total page 196 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is designed as an excellent resource text for students and professionals, providing an in-depth overview of the theory and applications of downhole microseismic monitoring of hydraulic fracturing. The readers will benefit greatly from the detailed explanation on the processes and workflows involved in the acquisition design modeling, processing and interpretation of microseismic data.

Download or read book Geomechanical Studies of the Barnett Shale Texas USA written by John Peter Vermylen and published by Stanford University. This book was released on 2011 with total page 143 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 Fluid Induced Seismicity written by Serge A. Shapiro and published by Cambridge University Press. This book was released on 2015-04-23 with total page 299 pages. Available in PDF, EPUB and Kindle. Book excerpt: The characterisation of fluid transport properties of rocks is one of the most important, yet difficult, challenges of reservoir geophysics, but is essential for optimal development of hydrocarbon and geothermal reservoirs. This book provides a quantitative introduction to the underlying physics, application, interpretation, and hazard aspects of fluid-induced seismicity with a particular focus on its spatio-temporal dynamics. It presents many real data examples of microseismic monitoring of hydraulic fracturing at hydrocarbon fields and of stimulations of enhanced geothermal systems. The author also covers introductory aspects of linear elasticity and poroelasticity theory, as well as elements of seismic rock physics and mechanics of earthquakes, enabling readers to develop a comprehensive understanding of the field. Fluid-Induced Seismicity is a valuable reference for researchers and graduate students working in the fields of geophysics, geology, geomechanics and petrophysics, and a practical guide for petroleum geoscientists and engineers working in the energy industry.

Download or read book Microseismicity written by S. A. Shapiro and published by . This book was released on 2008 with total page 67 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Unconventional Petroleum Geology written by Caineng Zou and published by Elsevier. This book was released on 2017-03-10 with total page 508 pages. Available in PDF, EPUB and Kindle. Book excerpt: Unconventional Petroleum Geology, Second Edition presents the latest research results of global conventional and unconventional petroleum exploration and production. The first part covers the basics of unconventional petroleum geology, its introduction, concept of unconventional petroleum geology, unconventional oil and gas reservoirs, and the origin and distribution of unconventional oil and gas. The second part is focused on unconventional petroleum development technologies, including a series of technologies on resource assessment, lab analysis, geophysical interpretation, and drilling and completion. The third and final section features case studies of unconventional hydrocarbon resources, including tight oil and gas, shale oil and gas, coal bed methane, heavy oil, gas hydrates, and oil and gas in volcanic and metamorphic rocks. - Provides an up-to-date, systematic, and comprehensive overview of all unconventional hydrocarbons - Reorganizes and updates more than half of the first edition content, including four new chapters - Includes a glossary on unconventional petroleum types, including tight-sandstone oil and gas, coal-bed gas, shale gas, oil and gas in fissure-cave-type carbonate rocks, in volcanic reservoirs, and in metamorphic rocks, heavy crude oil and natural bitumen, and gas hydrates - Presents new theories, new methods, new technologies, and new management methods, helping to meet the demands of technology development and production requirements in unconventional plays

Download or read book Petroleum Abstracts written by and published by . This book was released on 1995-03 with total page 606 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Unconventional Reservoir Geomechanics written by Mark D. Zoback and published by Cambridge University Press. This book was released on 2019-05-16 with total page 495 pages. Available in PDF, EPUB and Kindle. Book excerpt: Since the beginning of the US shale gas revolution in 2005, the development of unconventional oil and gas resources has gathered tremendous pace around the world. This book provides a comprehensive overview of the key geologic, geophysical, and engineering principles that govern the development of unconventional reservoirs. The book begins with a detailed characterization of unconventional reservoir rocks: their composition and microstructure, mechanical properties, and the processes controlling fault slip and fluid flow. A discussion of geomechanical principles follows, including the state of stress, pore pressure, and the importance of fractures and faults. After reviewing the fundamentals of horizontal drilling, multi-stage hydraulic fracturing, and stimulation of slip on pre-existing faults, the key factors impacting hydrocarbon production are explored. The final chapters cover environmental impacts and how to mitigate hazards associated with induced seismicity. This text provides an essential overview for students, researchers, and industry professionals interested in unconventional reservoirs.

Download or read book Onshore Unconventional Hydrocarbon Development written by National Academies of Sciences, Engineering, and Medicine and published by National Academies Press. This book was released on 2018-07-26 with total page 55 pages. Available in PDF, EPUB and Kindle. Book excerpt: Oil and gas well completion and stimulation technologies to develop unconventional hydrocarbon resources in the United States have evolved over the past several decades, particularly in relation to the development of shale oil and shale gas. Shale oil and shale gas resources and the technology associated with their production are often termed "unconventional" because the oil and gas trapped inside the shale or other low-permeability rock formation cannot be extracted using conventional technologies. Since about 2005, the application of these technologies to fields in the U.S. have helped produce natural gas and oil in volumes that allowed the country to reduce its crude oil imports by more than 50% and to become a net natural gas exporter. The regional and national economic and energy advances gained through production and use of these resources have been accompanied, however, by rapid expansion of the infrastructure associated with the development of these fields and public concern over the impacts to surface- and groundwater, air, land, and communities where the resources are extracted. A workshop on December 1 and 2, 2016 at the National Academy of Sciences in Washington, DC, explored the management of risk related to the development of onshore unconventional oil and gas resources such as shale oil and shale gas. The second part of the workshop, on December 2, addressed issues associated with induced seismicity and managing the risk of induced seismic events associated with development of oil and gas fields. This publication summarizes the presentations and discussions from this second day of the workshop.

Download or read book Microseismicity a tool for reservoir characterization written by S. A. Shapiro and published by . This book was released on 2008 with total page 67 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book An Example of Using Oil production Induced Microseismicity in Characterizing a Naturally Fractured Reservoir written by and published by . This book was released on 1996 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt: Microseismic monitoring was conducted using downhole geophone tools deployed in the Seventy-Six oil field, Clinton County, Kentucky. Over a 7-month monitoring period, 3237 microearthquakes were detected during primary oil production; no injection operations were conducted. Gross changes in production rate correlate with microearthquake event rate with event rate lagging production-rate changes by about 2 weeks. Hypocenters and first-motion data have revealed low-angle, thrust fracture zones above and below the currently drained depth interval. Production history, well logs and drill tests indicate the seismically-active fractures are previously drained intervals that have subsequently recovered to hydrostatic pressure via brine invasion. The microseismic data have revealed, for the first time, the importance of the low-angle fractures in the storage and production of oil in the study area. The seismic behavior is consistent with poroelastic models that predict slight increases in compressive stress above and below currently drained volumes.