Abstract
Studying the CPAD in a petroleum-rich super basin is a vital task that help to provide deep understanding of the petroleum accumulation mechanism (PAM) and the petroleum distribution pattern (PDP). Sirt Basin, with middle-mature exploration stages, usually imposes key concerns about the authentic estimated petroleum reserves, and most importantly, the remaining undiscovered resource potential (RUP). The current CPAD study established to provide a key reasonable explanation of the main parameters that govern the current discovered and possible remaining resource potential in a nearly 600,000 sq. km area. Typical basin data from various sources and types including, basin geology, subsidence and thermal maturity, and organic geochemistry of the source rocks and crude oils, were successfully integrated with a suitable refined regional multi-dimensional basin model. Five major reasons were defined that seem to impact the PAM and incentivize the entire Sirt Basin to develop huge amount of petroleum phases at different levels (burials) and locations, such as (1) Rifting phases and the plunged oblique SW.NW overall basin structure style (onshore/offshore), including two major tectonic features, troughs (source host) and platforms (reservoir host), (2) Multi-stacked mature and high-quality source facies dominated by marine, lacustrine, and terrestrial organofacies (B, C, and D/E), (3) Proper timing of early trap formation and positioning followed by later enough petroleum charge access (PCA), (4) Presence of conventional high quality clastic (lower basin section) and carbonate reservoirs (common middle/upper section), (5) A continues light oil and low Sulphur (less than 1.4) petroleum phase generated and expelled (charge volumes), and migrated/accumulated in well-sealed middle to large size structural and combined traps (Meso-Cenozoic). Taking into account the aforementioned reasons, achieving successful exploration optimization in the Sirt Basin, whether for conventional (e.g., offshore) or unconventional programs, necessitates the completion of thoroughly integrated basin and petroleum systems analysis studies (BPSA). These studies should be approached as a unified basin study, encompassing both onshore and offshore aspects.