OIL TO SOURCE CORRELATION FOR DETECT HYDROCARBON ORIGIN AND MIGRATION ON OFFSHORE SOUTHWEST SALAWATI BASIN

摘要

Oil to source correlation is very important to know about hydrocarbon in an area. This correlation is very attractive for hunting new hydrocarbon in prospect area, in this case such as in Salawati Basin. There was no well in offshore area which drilled until source rock, then the source rock sampel was taken from well on Salawati Island. Due to this weakness, geochemical method is important for detecting hydrocarbon origin and migration on offshore area.Positive correlation between oil and source rock showed on offshore wells. These equal look on GC, GC-MS, and Carbon Isotop character. GC, GC-MS, and Carbon Isotop data show that oil and source rock origin from marine with anoxic until sub-oxic depositional condition.. That could be appear from Gammacerana (show on hypersaline condition), abundance Oleanane (growth of Angiosperame on tertiary age), Pr/Ph have range 1-3 (show the sub-oxic depositional condition), C29/C30 hop low character (marine indication).Migration patterns was on offshore area have direction of northeast-southwest. That perpendicular with bedding formation, that things has been showing from sub-surface map, which showed depression area in north and high area in south. It was according to fault pattern on offshore area.Combination of two data show that hydrocarbon on offshore area origin from north and migration pattern perpendicular to bedding formation, especially Kais Formation as a reservoir and Klasafet Formation as a source rock sample.