Integrating pressure data from formation tester tools and DSTs to characterize deepwater fields, East Kalimantan, Indonesia

In the past 3 years, two significant commercial hydrocarbon accumulations i n the deep waters of the Makassar Strait, Indonesia, were discovered. These fields are located approximately 16 miles northeast of the giant Attaka fi eld in 1,400 to 3,400 ft of water. To date, more than 40 exploration and appraisal wells have been drilled in both fields, and extensive pressure data have been collected by formation t ester tools and drillstem tests (DSTs). The pressure data. used with other data such as seismic and well logs. have enabled us to characterize deepwat er turbidite sand reservoirs. In this deepwater environment. DSTs are used selectively and only with stro ng justification because of their prohibitive cost. Instead, the use of the pressure-testing tool is pushed to its limit to gain extensive data on pre ssure, rock, and fluid properties conventionally obtained by DSTs. This paper will show how the deepwater reservoirs were characterized by mea ns of pressure data from formation tester tools and DSTs to complement geol ogical and seismic data interpretations. Reservoir characteristics such as fluid type, fluid contacts. reservoir connectivity, and sand geometry can b e inferred from the pressure gradients and pressure transients. These data are used in constructing reservoir fluid-flow models for a field-developmen t plan.