Author :
Publisher :
Page : 5 pages
File Size : 27,97 MB
Release : 1999
Category :
ISBN :
A 500-ft length, 6-level, 3-component, vertical geophone array was permanently deployed within the upper 800 ft of Unocal's well GDCF 63-29 during a plug and abandonment operation on April 7, 1998. The downhole array remains operational after a period of 1 year, at a temperature of about 150 C. Continuous monitoring and analysis of shallow seismicity (
Author : Ravi Batra
Publisher :
Page : pages
File Size : 18,86 MB
Release : 1984
Category : Geothermal engineering
ISBN :
Author :
Publisher :
Page : 8 pages
File Size : 34,90 MB
Release : 1994
Category :
ISBN :
This report summarizes the efforts of LBL to utilize MEQ data in reservoir definition as well as in evaluating its performance. Results of the study indicate that the velocity and attenuation variations correlate with the known geology of the field. At the NW Geysers, high velocity anomalies correspond to metagraywacke and greenstone units while low velocity anomalies seem to be associated with Franciscan melanges. Low Vp/Vs and high attenuation delineate the steam reservoir suggesting undersaturation of the reservoir rocks. Ongoing monitoring of Vp/Vs may be useful in tracking the expansion of the steam zone with time. Spatial and temporal patterns of seismicity exhibit compelling correlation with geothermal exploitation. Clusters of MEQs occur beneath active injection wells and appear to shift with changing injection activities. High resolution MEQ locations hold promise for inferring fluid flow paths, especially in tracking injectate. This study has demonstrated that continuous seismic monitoring may be useful as an active reservoir management tool.
Author :
Publisher :
Page : 10 pages
File Size : 42,42 MB
Release : 1993
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During the last several years Lawrence Berkeley Laboratory (LBL) and Lawrence Livermore National Laboratory (LLNL) have been working with industry partners at The Geysers geothermal field to evaluate and develop methods for applying the results of microearthquake (MEQ) monitoring. It is a well know fact that seismicity at The Geysers is a common occurrence, however, there have been many studies and papers written on the origin and significance of the seismicity. The attitude toward MEQ data ranges from being nothing more than an curious artifact of the production activities, to being a critical tool in evaluating the reservoir performance. The purpose of the work undertaken b y LBL and LLNL is to evaluate the utility, as well as the methods and procedures used in of MEQ monitoring, recommend the most cost effective implementation of the methods, and if possible link physical processes and parameters to the generation of MEQ activity. To address the objectives above the MEQ work can be categorized into two types of studies. The first type is the direct analysis of the spatial and temporal distribution of MEQ activity and studying the nature of the source function relative to the physical or chemical processes causing the seismicity. The second broad area of study is imaging the reservoir/geothermal areas with the energy created by the MEQ activity and inferring the physical and/or chemical properties within the zone of imaging. The two types of studies have obvious overlap, and for a complete evaluation and development require high quality data from arrays of multicomponent stations. Much of the effort to date at The Geysers by both DOE and the producers has concentrated establishing a high quality data base. It is only within the last several years that this data base is being fully evaluated for the proper and cost effective use of MEQ activity. Presented here are the results to date of DOE's effort in the acquisition and analysis of the MEQ data.
Author : David W. Eaton
Publisher : Cambridge University Press
Page : 377 pages
File Size : 45,62 MB
Release : 2018-04-26
Category : Science
ISBN : 1108596665
The past few decades have witnessed remarkable growth in the application of passive seismic monitoring to address a range of problems in geoscience and engineering, from large-scale tectonic studies to environmental investigations. Passive seismic methods are increasingly being used for surveillance of massive, multi-stage hydraulic fracturing and development of enhanced geothermal systems. The theoretical framework and techniques used in this emerging area draw on various established fields, such as earthquake seismology, exploration geophysics and rock mechanics. Based on university and industry courses developed by the author, this book reviews all the relevant research and technology to provide an introduction to the principles and applications of passive seismic monitoring. It integrates up-to-date case studies and interactive online exercises, making it a comprehensive and accessible resource for advanced students and researchers in geophysics and engineering, as well as industry practitioners.
Author : T. Kishi
Publisher : Elsevier
Page : 243 pages
File Size : 47,88 MB
Release : 2000-09
Category : Science
ISBN : 0080438512
The theme of the 15th International Acoustic Emission Symposium (IAES15) was set as 'practicality for life-extension and maintenance of plants and structures'. Special emphasis was placed on the review of acoustic emission (AE) research and applications in the 20th century and its future in the 21st century. The technique for monitoring defects and abnormal vibrations due to machine failures is vitally important for the safety of structures in a modern society. AE, as a passive, rather than an active NDT method, has drawn much attention because of its applicability to on-stream surveillance of structures. One important point is its capability to acquire data very simply but with high sensitivity so that the development of a non-contact sensing technique is particularly important. A quantitative method to evaluate structural integrity and remaining life from the detected AE signals is strongly required. Quantitative analysis, based on inverse procedures, has provided a certain solution, but has not been utilized widely enough in structures due to its complexity. Its applicability is limited partly because the accuracy of solutions depends on noise levels and partly because the phenomenon is usually non-reproducible. AE is expected to be a next-generation technique not only to monitor conditions but also for the repair of damaged structures, combined with an active-adaptive technique using a 'solid state actuator'. 'Smart Materials and Structures' are known in this respect. AE is considered to be a very promising technique, together with such sensing techniques as optical fiber, shape memory alloy and electro-rheological fluid. Thus, AE can play a very important roll in monitoring, evaluating and repairing structures. In this workshop, a limited number of invited papers are presented for technical discussion to review the achievements of AE research and applications in the 20th century. The proceedings are entitled Acoustic Emission - Beyond the Millennium to celebrate the new millennium, and stepping forward to a new era. The authors and topics of these review papers were selected by the editorial board.
Author :
Publisher :
Page : 7 pages
File Size : 26,39 MB
Release : 1998
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ISBN :
In collaboration with UNOCAL Geothermal Operations, Los Alamos National Laboratory assessed the feasibility of using vertical arrays of borehole seismic sensors for mapping of microseismicity in The Geysers geothermal field. Seismicity which arises from minute displacements along fracture or fault surfaces has been shown in studies of seismically active oil reservoirs to be useful in identifying fractures affected by and possibly contributing to production. Use of retrievable borehole seismic packages at The Geysers was found to reduce the threshold for detection of microearthquakes by an estimated 2--3 orders of magnitude in comparison to surface-based sensors. These studies led to the design, materials selection, fabrication, and installation of a permanent array of geophones intended for long term seismic monitoring and mapping of fractures in the vicinity of the array at The Geysers.
Author : Cezar I. Trifu
Publisher : Birkhäuser
Page : 632 pages
File Size : 45,6 MB
Release : 2012-12-06
Category : Science
ISBN : 3034881797
Author : Geothermal Resources Council. Annual Meeting
Publisher :
Page : 598 pages
File Size : 46,55 MB
Release : 1999
Category : Geothermal engineering
ISBN :
Author :
Publisher :
Page : pages
File Size : 33,63 MB
Release : 2007
Category :
ISBN :
Seismic stimulation is a proposed enhanced oil recovery(EOR) technique which uses seismic energy to increase oil production. Aspart of an integrated research effort (theory, lab and field studies), LBNL has been measuring the seismic amplitude of various stimulationsources in various oil fields (Majer, et al., 2006, Roberts, et al.,2001, Daley et al., 1999). The amplitude of the seismic waves generatedby a stimulation source is an important parameter for increased oilmobility in both theoretical models and laboratory core studies. Theseismic amplitude, typically in units of seismic strain, can be measuredin-situ by use of a borehole seismometer (geophone). Measuring thedistribution of amplitudes within a reservoir could allow improved designof stimulation source deployment. In March, 2007, we provided in-fieldmonitoring of two stimulation sources operating in Occidental (Oxy)Permian Ltd's South Wasson Clear Fork (SWCU) unit, located near DenverCity, Tx. The stimulation source is a downhole fluid pulsation devicedeveloped by Applied Seismic Research Corp. (ASR). Our monitoring used aborehole wall-locking 3-component geophone operating in two nearbywells.
