3D basin and petroleum system modelling of the early cretaceous play in the NW Persian Gulf

Abstract

Petroleum systems analysis has become a key part of hydrocarbon resource exploration. Early Cretaceous petroleum system in the northwest of the Persian Gulf basin with prolific source rocks and reservoirs, is the main petroleum system in the region. Most Iranian offshore oils have been stored in this geological interval. Recent studies indicate that finding new resources is still possible. Therefore, for the first time, this study applied a 3D petroleum system modeling approach to predict new prospects based on available seismic and well data in ∼30,000 km2 area. Results showed that the Berriasian Garau, Albian Kazhdumi and Barremian upper Gadvan are the dominant source rocks. Most of the hydrocarbons have originated from the two Binak and Northern troughs as oil kitchens in the northern and northwest areas. Most anticlines formed in the Late Cretaceous before the critical moment of the source rocks. At first, traps adjacent to the Binak and Northern troughs oil kitchens were charged. Then, hydrocarbon migrated laterally to the far structures. The activity of normal faults has played an important role in vertical migration and reservoir oil mixing, especially in oilfields located above the Khafji-Norooz Arch. Albian Burgan sandstone distribution map from process-based forward stratigraphic modeling suggests low probability of stratigraphic traps. Nonetheless, the Burgan anticline reservoirs have the highest oil in place because they have broad drainage area. Finally, three new anticlinal traps with significant oil reserves were identified in the Yamama, Burgan, and Khalij formations in the northwest of the study area. Results of this study help to better understand Early Cretaceous petroleum system performance and identify new hydrocarbon prospects in the study area.