Abstract: In recent years, a series of major oil and gas discoveries have been made in the Upper Cretaceous turbidite sandstones in Guyana Basin, which increases the confidence of further exploration. The primary issue facing the petroleum exploration includes the differences in hydrocarbon accumulation patterns in various zones and reservoir sections, as well as the further exploration orientations. After studying tectono-sedimentary evolution, hydrocarbon accumulation conditions, oil and gas distribution, hydrocarbon accumulation pattern and main controlling factors, the differences in hydrocarbon accumulation in various zones of Guyana Basin are systematically analyzed and the further exploration orientation is determined. The study results indicate that Guyana Basin experienced four major stages of tectonic evolution, i.e., pre-rift, early rift, late rift, and passive margin, and four deposition zones were divided in the basin, including coastal plain, continental shelf, continental slope, and deep-water basin. Two sets of effective hydrocarbon source rocks are developed in the Basin: high-quality marine source rocks of the Cenomanian Stage during the passive margin period, and lacustrine source rocks of the Upper Triassic to Lower Jurassic strata during the early and late rift stages. The distribution of oil and gas shows characteristics of “vertical layering” and “planar zoning”. The main hydrocarbon accumulation play was developed in the Upper Cretaceous in continental slope zone, such as the large-scale turbidite sandstone oil reservoirs. Three types of hydrocarbon accumulation models are classified as a whole, namely near-source hydrocarbon accumulation, lateral medium-distance hydrocarbon migration and accumulation, and lateral long-distance hydrocarbon migration and accumulation. The continental slope zone and deep-water basin zone are dominated by near-source hydrocarbon accumulation model, which is the main hydrocarbon accumulation model in the basin, and the enrichment of oil and gas is mainly controlled by high-quality reservoir. The continental shelf zone is mainly characterized by lateral medium-distance hydrocarbon migration and accumulation, and sealing capacity and reservoirs are the main controlling factors. The coastal plain zone is characterized by lateral long-distance hydrocarbon migration and accumulation model, with the main controlling factors including source rock, migration pathway, and densification mechanism. The further exploration should focus on turbidite sandstones in continental slope zone, and attach equal importance to oil and gas, with two important orientations in the northwest and northeast zones.

Key words: hydrocarbon accumulation model, controlling factor, structural zones, exploration orientation, Guyana Basin