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Example Results From the King Mine Strong-Motion Station <br /> -P. Swanson, NIOSH/Spokane Research Laboratory <br /> As part of a technology transfer component of <br /> a NIOSH mine safety research project, a ....._ �...� .. <br /> triaxial strong-motion seismometer and <br /> vertical velocity seismometer were deployed <br /> at the King Mine in the fall of 2004. The <br /> sensors and data recording unit,as well as <br /> radio telemetry hardware and data processing rc - <br /> and display software, were demonstrated as <br /> potential components of a seismic monitoring WTM. 1 <br /> array contemplated by the Bowie Resources — <br /> longwall coal mine(Paonia, CO). j _ BWK rg <br /> The constituent parts of the King Mine station wr„ , <br /> (BWK)are illustrated and examples of some <br /> of the different types of raw data displays are shown below. <br /> A cursory analysis of data collected during the time period September 17 through <br /> November 18, 2004 was performed. Based upon the difference in arrival times of <br /> different types of seismic waves, one can estimate the distance the waves have traveled <br /> from its source. In this case, differences between arrival times of the first arriving P <br /> wave and slower arriving shear and/or surface waves were estimated. The time <br /> differences, or S-P times,become larger as waves travel farther. Events were observed to <br /> fall into three groups with similar S-P times, suggesting that the distances to the events <br /> fell into three different ranges (note- this type of measurement estimates range but not <br /> bearing). <br /> As three different longwall coal mines operate in the immediate vicinity of the King <br /> Mine, these three different S-P time groupings likely indicate events originating at the <br /> three different mines. Seismic events with magnitude greater than 2.5 are detected and <br /> reported by the U.S. Geological Survey. However, due to a lack of nearby stations,the <br /> calculated locations are not sufficiently accurate to be able to positively associate them <br /> with a specific mine. <br />