دیکشنری تخصصی مهندسی نفت - نسخه آنلاین

n: the theory that the earths landforms assumed their present configuration in a brief episode at the beginning of geologic history-possibly in a single great catastrophic event-and have remained relatively unchanged since that time. Compare uniformtarianism. catcher n: a device fitted into a junk basket that retains the junk picked up by the basket catch samples v: to obtain cuttings for geological information as formations are penetrated by the bit The samples are obtained from drilling fluid as it emerges from the wellbore or, in cable-tool drilling, from the bailer. Cuttings are carefully washed until they are free of foreign matter, dried, and labelled to indicate the depth at which they were obtained.

n: a recognisable. naturally formed physical land feature having a characteristic shape. such as a plain. alluvial fan. valley. hill. or mountain.