A review of the development of a digital log database for petroleum exploration

Abstract

Modern petroleum exploration, incorporating routine acquisition of geophysical logs, began in Australia in the mid 1950s. Prior to 1976, data were recorded in analog form. By 1982, digital recording was routine for most logging units, and since 1985 few operators have accepted non-digital records. Approximately 60% of the log data acquired to date in Australia is thus analog. Varying standards of recording practice, evolving hardware and changes in drilling practice have all affected the quality of analog records, and their ease of use. The economics of use are often highly dependent on record quality. In 1981 Wiltshire Geological Services began systematic high fidelity conversion of analog data to digital. Our initial objectives were to develop tools for better and more efficient analysis of sedimentary sequences and basin evolution. By 1985 the developing data set was clearly a major asset. Since then we have built the data set as rapidly as possible whilst maintaining the highest possible data conversion standards. Resulting benefits include: data preservation is assured; data are standardized and enhanced by editing of noise; data reproduction is easier and cheaper; end-user working material is routinely tailored to specific job needs; worker efficiency is dramatically improved. Intangible benefits may arise from better interpretive use of the data in exploration.