Determination of Horizontal and Vertical Permeabilities Using Multiprobe Wire line Formation Tester in Layered Formations

A new interpretation technique is described for determining the horizontal and vertical permeabilities and the porosity-total compressibility product using a multiprobe wireline formation tester. The multi probe tester (tool) provides the capability to conduct controlled local production and interference tests along an openhole. It also permits flexible configuration. In this paper, we describe a three-probe configuration that consists of a sink, a diametrically opposite horizontal observation probe, and one vertically displaced observation probe. Pressure measurements from two observation probes are used for the estimation of unknown formation parameters. In layered and heterogeneous formations, this configuration allows one to test interlayer communication and to determine individual layer properties. The interpretation technique is applied for the estimation of the layer horizontal and vertical permeabilities and the porosity and total compressibility product for a carbonate formation in an offshore field in Abu Dhabi. Introduction In this paper, we present a new technique for determining horizontal and vertical permeabilities and storativity (the porosity and total compressibility product) using the multi probe wireline formation tester (MDT* Modular Formation Dynamics Tester1) pressure measurements. The multiprobe tester provides the capability to conduct controlled local production and interference tests in openhole wells as well as permits flexible configuration. The formation pressures along the well bore are measured at three different locations by a sink (production) probe and two observation probes, as shown in Fig. l. The first observation probe is called horizontal probe, which is diametrically opposite from the sink probe. The second observation probe is called vertical probe, which is vertically displaced at a distance of 2.3 ft from the sink probe.