To provide the U.S. mining and energy industries with information in the selection of seismic detectors for high-resolution applications, the Bureau of Mines evaluated 35 velocity detectors (geophones) and 9 accelerometers. It was found that velocity detectors with natural frequencies from 10 to 100 hz were effective for seismic studies in the 5- to 600-hz spectrum and that accelerometers were most effective in the 100- to 1,000-hz range. Although the accelerometers described in this report performed about equally with the better velocity detectors tested, the accelerometers showed higher output voltage levels at higher frequencies, which is an advantage. It is important that a seismic detector and its intended purpose be matched properly to achieve the intended results in high- resolution applications. There are many factors that could affect proper matching, thus careful selection of the best detector for a particular application must be exercised.