Publications

Hydrocarbon generation within a back-arc basin is influenced by the basin history itself. In general, the back-arc basin is formed by a thinning of the crust, resulting from a rifting mechanism. Such thinning will reduce the distance between the sedimentary basin and the mantle as a heat source, thus increasing the heat in a sedimentary basin. The rift phase is followed by a sag phase, characterized by a decline in heat as a result of the cooling of the upper mantle, which then forms a new crust. A magmatism phase taking place within the sag phase generates a heat flow. The methods used in the reconstruction of a hydrocarbon maturation history involve reconstructing a temperature history through time, one which later changes into a hydrocarbon maturation history through the Arhenius kinetic model. The hydrocarbon maturity model will be compared with measurements of vitrinite reflectance data. Obtaining a hydrocarbon maturity model corresponding to the measurement data is achieved by changing the value of the Paleo-heat flow, we need to consider the timing of the rifting phase, that will lead to the addition of a heat flow resulting from the shrinking distance from the deposition of sediments into the mantle, which acts as a heat source. The hydrocarbon maturity model calibration revealed from hydrocarbon maturity data is created by reconstructing the Paleo-heat flow, increased at the rifting phase, decreased at the sag phase and increased again at the end of the deposition. This is a case study in hydrocarbon maturation modeling, performed on several wells in the South Sumatra Back-arc Basin. The result is that there are five warming history phases: [1] an increase in heat flow during the rifting phase (30.5-25 Ma), [2] the heat flow decreases during the sag phase (25-20 Ma), [3] the heat flow increases again, due to magmatism activity (20-10 Ma), [4] another decline in the heat flow, due to the cessation of magmatism activity (10-1.6 Ma) and [5] the heat flow rises once more, due to the final magmatism activity (1.6-0 Ma).