Abstract
This paper presents a discussion on the use of the Wireline Formation Tester (WFT) to identify oil-bearing intervals in a reservoir section that contains thinly-laminated, low-resistivity pay sections in the Ghadames Basin of southern Tunisia. Pay zones previously bypassed by conventional log analysis have been conclusively determined as oilbearing through use of the tool.
Three field examples are discussed on the use of the Downhole Fluid Analyzer (DFA) to determine hydrocarbon type and in-situ GOR for three different hydrocarbon phase environments.
The paper also discusses, again through use of field examples, how analysis of the post-DFA pressure response could be used to determine zonal producibility. This zonal producibility from the WFT is then compared to conventional well-test productivity. A close agreement exists between the WFT and conventional well-test productivity estimates. Thus, it eliminates the need for zones to be conventionally tested to determine productivity.
Finally, the paper provides a method to significantly reduce the time necessary to collect representative fluid samples through proper monitoring of the DFA data stream.
