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dc.contributor.authorWarren, Justin Cableen_US
dc.date.accessioned2017-04-04T19:49:05Z
dc.date.available2017-04-04T19:49:05Z
dc.date.issued2011-05-02en_US
dc.identifier.otheretd-05162011-151046en_US
dc.identifier.urihttp://hdl.handle.net/10919/76766
dc.description.abstractThis study involves seismic monitoring of a deep coal mine. The purpose is to examine the processes responsible for induced seismicity. A seismic network consisting of five three-component short-period seismometers located above the mine recorded the seismic data. The events discussed here occurred from March 1, 2009 until April 7, 2011 during the mining of three longwall panels and the data was telemetered to Blacksburg, Virginia. A correlation equation was developed to relate local magnitude estimated by automatic data processing software in near real-time to seismic moment for well-recorded events. Local magnitude is a relative measure of relative size for a suite of earthquakes, while seismic moment is an objective measure of the actual physical size. Using the calculated seismic moments, we calculated "moment magnitudes" (Mw) for all events, which allowed us to do further studies in terms of their absolute size as a function of both time and space. The results indicate that there are two distinct classes of seismic events at the mine. The first class consists of small (M<=0) earthquakes recorded near the moving mine face. The second class of seismicity occurs in the mined-out "gob" area of the longwall panel at a greater distance behind the moving face. Their occurrence and relation to the mining history, depth of overburden and geology of the roof rocks is a significant interest. Results show that thick overburden due to elevated topography has a positive correlation with the number of seismic events but is not the only controlling factor; other factors include gob size and geological variability. Another important observation is the high seismic attenuation of the rock mass above the mine. This appears to be the result of the fracturing and caving processes associated with the creation of the gob and the resulting subsidence of the ground surface.
dc.language.isoen_USen_US
dc.publisherVirginia Techen_US
dc.rightsI hereby certify that, if appropriate, I have obtained and attached hereto a written permission statement from the owner(s) of each third party copyrighted matter to be included in my thesis, dissertation, or project report, allowing distribution as specified below. I certify that the version I submitted is the same as that approved by my advisory committee. I hereby grant to Virginia Tech or its agents the non-exclusive license to archive and make accessible, under the conditions specified below, my thesis, dissertation, or project report in whole or in part in all forms of media, now or hereafter known. I retain all other ownership rights to the copyright of the thesis, dissertation or project report. I also retain the right to use in future works (such as articles or books) all or part of this thesis, dissertation, or project report.en_US
dc.subjectSpatial Distributionen_US
dc.subjectMicroseismicen_US
dc.subjectMoment Magnitudeen_US
dc.subjectMining Induceden_US
dc.subjectQuality Factoren_US
dc.titleA Study of Mine-Related Seismicity in a Deep Longwall Coal Mineen_US
dc.typeThesisen_US
dc.contributor.departmentGeophysicsen_US
dc.description.degreeMaster of Scienceen_US
thesis.degree.nameMaster of Scienceen_US
thesis.degree.levelmastersen_US
thesis.degree.grantorVirginia Polytechnic Institute and State Universityen_US
thesis.degree.disciplineGeophysicsen_US
dc.contributor.committeechairChapman, Martin C.en_US
dc.contributor.committeememberHole, John A.en_US
dc.contributor.committeememberSnoke, J. Arthuren_US
dc.type.dcmitypeTexten_US
dc.identifier.sourceurlhttp://scholar.lib.vt.edu/theses/available/etd-05162011-151046/en_US
dc.date.sdate2011-05-16en_US
dc.date.rdate2016-10-18
dc.date.adate2011-06-16en_US


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