Source rock characterization in frontier basins – a global approach
Exploring in frontier basins carries with it the challenge of identifying and derisking hydrocarbon play elements where well data and consequently, lithological and stratigraphic information is often sparse to absent. In this setting, seismic data will typically be the only source of information available to identify potential play fairways and derisk the corresponding petroleum system elements. Until recently, the exploration focus of seismic interpretation has predominantly been on developing methodologies to identify structure, traps and reservoir rather than interrogate source rocks. Geophysical deconstruction of the data again focuses on categorizing hydrocarbon-bearing reservoirs, including AVO/AVA (Amplitude vs Offset/Angle) analysis, bright spot/dim spot and flat spot identification. Yet the lack of focus on source is curious as, particularly in frontier basins, the ability to derisk presence and effectiveness (total organic carbon percentage (TOC%) and maturity) of a viable source is key. Therefore, a study has been undertaken to evaluate a number of basins and to characterize the hydrocarbon system and source rocks therein. In conducting this study we have developed a workflow and characterization criteria that provides a significant development in the ability to derisk unproven hydrocarbon plays. Spectrum has developed a systematic approach for identifying working hydrocarbon systems in undrilled or frontier basins. This workflow is currently being applied to all frontier basins in which Spectrum operates, and in this study the results from a sample of four such basins is presented as well as how lessons learnt in a given basin can provide insight into on-trend and conjugate margins.