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•r <br />Example Results 1•-rom the Kin;; dine titrunl;-~lutiun Station <br />-P. S\\"an.cm, \IO~II Spokane Rixx:u'cft I ahurltorv <br />~1s part of a technology transfer component of <br />a \IUSFi mine safety research project, a <br />tri;vial strong-nxtlion scisnnxnctcr and <br />vertical velocity scisnunnetcr tccre deployed <br />at the pine mine in the fan of _'otu. "fhe <br />sensors and data recording unit. as well as <br />radio telemetry hardware and data prcxessinc <br />and displa} solhvarc, were demonstrated as <br />potential components of a seismic monitoring <br />array eontemplatcd by the L3o\vic Kesources <br />longwall coal mine Ipaunia, C'O). <br />1'hc constituent parts of the Kin,_ Mine station <br />1 BW'K) arc illustrated and ex;unplcs of unite <br />of the diftorcnt types ~,f raw data displays arc shown below. <br />A cursory analysis of data collected during the time i+eriod September 17 through <br />Vuvemlxr I S, 2QI)4 was pcrfonncd. 13ascd ulxm the dif7crencc in arrival times of <br />different tyixs of seistntc \caves, one can estimate the distance the waves have travclyd <br />from its source. In this case, dittcrcnces between arrival tinter of the tint arciving P <br />wave :utd slo\vcr arriving shear and,'or surface waves were estimated. '1°hc time <br />diflcrcnces, or S-P times, hccclme larger as waves travel Gtrther. Events weft: observed to <br />tall into three groups with similar S-P times, suggesting that the dist:utces to the events <br />fell into three difTcrcnt ranges mote - this type of measurement estimates range but not <br />hcarincl. <br />:\s three ditlcrcnl Iongwall coal mines operue in the inunedtatc vicinity of the King <br />~1inc, these three difcrent S-P time groupings likely indicate events originating at the <br />three different mines. Seismic events with magnitude greater than 2.5 arc detected and <br />reported by the U.S. Geological Sur\•cy. However. due hl a lack ofneurby stations, the <br />calcul:ucd Icxations are not suflicicntly accurate to lax able to positively asscxiate them <br />with a specific mine. <br />