A SEISMIC SENSOR

摘要

A seismic sensor contains a geophone disposed within a housing (11b). The sensor is also provided with locking means (14, 19, 13) that can either lock the geophone relative to the housing, or can allow the geophone to rotate within the housing. The geophone is enclosed in a casing (17) which is so constructed that the overall mass distribution of the casing and geophone is uneven. The casing and assembly thus adopt a preferred orientation when the sensor is unlocked. A liquid can be disposed within the housing, so that the casing (17) and geophone can float when the sensor is unlocked.