PROCESS AND SYSTEM FOR DETECTING A NATIVE RESERVOIR FLUID IN A WELL BORE

摘要

A SYSTEM FOR DETECTING A NATIVE RESERVOIR FLUID IN A WELL BORE In order to detect the presence of a native reservoir fluid within a well bore, an auxiliary drilling fluid is injected into the borehole and recovered after it has circulated within the borehole. The detection system comprises a pressure-wave generator, an upstream pressure sensor for detecting the pressure wave as it passes through a first pipe in which the auxiliary drilling fluid circulates in the uncontaminated state, an outlet pressure sensor for detecting the pressure wave as it passes through a second pipe in which the auxiliary drilling fluid circulates and may be contaminated by a reservoir fluid which has entered the drilling fluid at any point of the well bore.