Abstract: Disclosed is a formation testing tool for extracting formation fluid from an earth formation penetrated by a borehole having a drilling fluid. The tool includes: a sample flow element configured to extract formation fluid from the formation in a sample zone; a sample zone seal forming a perimeter defining the sample zone; a contamination removal flow element configured to extract formation fluid contaminated with the drilling fluid from a contamination removal zone in the formation; a contamination removal zone seal forming a perimeter defining the contamination removal zone, which surrounds and excludes the sample zone; and a controller configured to control a sample flow rate in the sample flow element and a contamination removal flow rate in the contamination flow removal element in order to decrease an amount of time required to acquire a sample of the formation fluid having an acceptable amount of contamination.

Abstract: Disclosed is a formation testing tool for extracting formation fluid from an earth formation penetrated by a borehole having a drilling fluid. The tool includes: a sample flow element configured to extract formation fluid from the formation in a sample zone; a sample zone seal forming a perimeter defining the sample zone; a contamination removal flow element configured to extract formation fluid contaminated with the drilling fluid from a contamination removal zone in the formation; a contamination removal zone seal forming a perimeter defining the contamination removal zone, which surrounds and excludes the sample zone; and a controller configured to control a sample flow rate in the sample flow element and a contamination removal flow rate in the contamination flow removal element in order to decrease an amount of time required to acquire a sample of the formation fluid having an acceptable amount of contamination.

Abstract: A whipstock assembly is provided for lowering within a cased wellbore, cutting a window through a casing for drilling a sidetrack borehole, and retrieving with conventional fishing tools. The whipstock assembly includes two separate whipstocks having different tapers, and which are releasibly coupled for separately retrieving from the cased wellbore. A barrier member is provided to prevent a tapered face of one of the whipstocks from wedging debris between the whipstock and the casing.