microseismic instrument

microseismic instrument

[¦mī·krə¦sīz·mik ′in·strə·mənt]
(mining engineering)
An instrument for the study of roof strata and supports; it is inserted in holes, drilled at selected points, for listening to subaudible vibrations that precede rock failure.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.