Sequence Stratigraphy in Frontier Regions: An Example from the Rebi Block, Arafura Sea, Eastern Indonesia
Parvita H. Siregar, Gerald R. Baum, and Christopher G. St.
The Rebi Block is currently in the early stages of hydrocarbon exploration. The subsurface geology of this area is only known from seismic reflection data. By applying seismic stratigraphy techniques, unconformities and condensed sections were recognized. These discontinuities were dated using paleontological information from the Kulka-I well, Northwest Shelf of Australia. With these age constraints, seven unconformities and three condensed sections were dated and correlated to the Exxon global sea level curve.
The chronostratigraphic charts for the Rebi Block and the Northwest Shelf of Australia have clarified the Mesozoic stratigraphy of the study area. The Exxon global sea level curve has refined the ages determined by conventional paleontological dating. The chart has also helped in predicting source, reservoir and seal potential within a time framework. Prospective stratigraphic traps were those related to the incised valleys at the southeastern part of the Rebi Block. Although basin floor fans were recognized on the seismic lines, these sand-prone depositional systems are buried too deeply for current exploitation Further projection of maturity data from Well Koba-1 indicated the source rock has reached maturity in the Rebi Block. By extrapolating the depth versus R[o] of Well Koba-1 t the study area, the oil window is predicted to occur at a depth of approximately 1829.27 meters and the gas window at 3,355 meters.
AAPG Search and Discover Article #91019©1996 AAPG Convention and Exhibition 19-22 May 1996, San Diego, California