CONTRIBUTION OF POST-2000'S PETROLEUM EXPLORATION IN INDONESIA TO SOME ISSUES OF TECTONICS: SOLUTIONS TO PROBLEMS, NEW KNOWLEDGE, AND HYDROCARBON IMPLICATIONS

摘要

Application of a new Oil and Gas Law (Law No. 22 Year 2001) and Minister Regulation No. 40, Year 2006 (regulating direct tender/direct offer for acquiring working area) have significantly enhanced petroleum exploration in Indonesia. There have been many areas surveyed by seismic and wells drilled, which had never occurred before 2000's. Many frontier areas with less understood geology and tectonics in western and eastern Indonesia have been explored. These activities have provided data which have enabled better understanding of some areas in Indonesia, resolving existing problems/debates, and providing new knowledge. Some tectonic issues of Indonesia's geology relating to these are addressed, based on new data. Existing problems/debates are resolved, such as: (1) the mechanism of opening and the nature of the basement of the North Makassar Straits, (2) the origin of the Sumba micro-continent, (3) the basement nature of Cendrawasih Bay, Papua. In addition, some issues are better defined using new data, such as: (4) the forearc areas from Sumatra to West Java, and (5) the foredeep areas of Seram-Tanimbar-Timor troughs. Some new knowledge of tectonics have arisen, such as: (6) the presence of Late Paleozoic-Mesozoic sections of the Gondwanan micro-continents in East Java and South Makassar Straits, and (7) the multiple rifts/terranes of the Gorontalo Basin. These tectonic issues, now better understood with new data, provide insight into how to explore the areas where the issues are. Improved understanding of geology and tectonics of these areas will provide better analyses and syntheses of basin configuration, stratigraphy, structure, and petroleum systems, hence resulting in better definition of exploration play concepts.