Abstract

This paper presents procedures and methods of testing and analyzing Indonesian reef oil and gas wells to determine the formation characteristics and well deliverabilities. The well tests are in five different oil fields, and one gas field. Most of the reservoirs have secondary porosity and permeability systems which allow high flow rates from individual wells. The bottomhole pressure drawdown on some of the best wells range from 2 to 15 psi at flow rates in excess of 10,000 BOPD. Conventional test analysis of individual drawdown and buildup are difficult even with high precision pressure recorders. Selection of correct pressure drawdown and Horner build up slopes on these type of wells are difficult to determine. Test analysis for determining formation characteristics of these wells are based on multipoint tests.

Buildup plots of wells with permeabilities of 10 to 100 millidarcies are shown that indicate a constant pressure boundary (active water drive) could be detected from test analysis.

Three types of tests and their analysis are presented in this paper, (1) Single flow and buildup, Buildup with and without a constant outer boundary pressure case, (2) Multipoint, isochronal and flow after flow, and (3) Single flow of long duration and buildup with constant pressure at inner boundary, are discussed in this paper.