Publications

A case study from three deep-water exploration wells drilling is discussed with emphasis on optimization of data acquisition program, application of new technologies to measure missing information, petrophysical model building, and using the model in a well for which only minimally sufficient logs were acquired before conducting a drillstem test (DST). The target reservoirs are sand channel complex sequences developed in the Miocene - Pliocene slope of the Makassar Strait, east Kalimantan, in a water depth ranging from 1500 to 2500 ft. A tiered approach to formation evaluation was adopted in the project. First, for the first two wells, the mud log and LWD served for early hydrocarbon spotting and fluid identification based on in-house developed mud log analysis methodology. After this, and in the case of hydrocarbon show, high- resolution modern logs on Wireline were acquired for accurate quantification of reserves in thick and thin-bedded reservoirs. A modern dielectric log was used to measure formation water salinity and estimate position of fluid contacts, a triaxial induction log and high -resolution image logs were the basis for the interpretation of saturation and permeability in thin-bedded reservoirs. Real-time data transmission and data interpretation provided sufficient information to plan formation testing. A downhole formation tester was use to obtained a pressure profile survey and to take fluid samples. The gathered detailed information in the first two wells was sufficient to understand the reservoir structure and it’s complexities, calibrate conventional logs to predict key petrophysical parameters, and apply the parameter for a consequent full well test in the third well. Third well was logged only with basic LWD and triaxial induction logs, the data were analyzed according to developed petrophysical model, and the well was tested. The adopted approach allowed us to identify all hydrocarbon-bearing intervals and study in detail the formation, and also considerably saved rig operating time both because of the balance of complimentary LWD and wireline logs and because of the reduced logging time in the 3rd well, for which only surface test was performed.