From Deposition to Preservation: Investigating Lower Cretaceous Source Rock in Suriname Basin through Forward Stratigraphic Modeling

With the growing hydrocarbon exploration activities in the Suriname Basin, numerous studies have been conducted to reduce the uncertainties related to the presence of the source rock. This study aimed to investigate the presence of basin-wide source rock distribution in the Lower Cretaceous stratigraphic intervals by employing a process-based Forward Stratigraphic Modelling (FSM) approach. FSM is a comprehensive methodology that seamlessly integrates diverse datasets and geological information to construct a 4D stratigraphic model. The model is iteratively calibrated and validated using available data including seismic data (thickness map) and well measurements (e.g., lithofacies, Total Organic Carbon (TOC), and Hydrogen Index (HI)). Our model captures the presence of potential mixed marine-terrigenous source rock within the Lower Cretaceous interval, consistent with oil geochemistry and isotope and gas data analyses. Source rock deposition is associated with an increase in continental input during the Late Barremian/early Aptian, with modeled initial HI ranging from 200 to 450 mgHC/gTOC and initial TOC ranging from 1.5 to 5.7 wt% as the main source rock potential. The outcomes of this FSM study serve as a critical input to the petroleum system model, facilitating a more robust assessment of hydrocarbon maturation, generation, migration, and trap-charge analysis for further derisking.