Abstract:

On the basis of the analysis of petroleum geological conditions and the known fields of the North Sakhalin basin in the Sea of Okhotsk, Russian Far East, the author summarized the oil and gas distribution features of the North Sakhalin basin, and then combining with the analysis of tectonic evolution, discussed the main controlling factors of hydrocarbon accumulation. The results show that the hydrocarbon distribution of this basin has the features that the scale of onshore reserves is much smaller than that of the sea shelf reserves, and it can be longitudinally divided into 2 large plays, however, the oil and gas are mainly enriched in the Dagi Formation and Nutovo Formation, which are obviously zonal in planar distribution, the Dagi Formation reservoirs are mainly distributed in the landward inner zone and the Notovo Formation reservoirs are mainly distributed in the outside zone far from land. The hydrocarbon accumulations are mainly controlled by multicycle tectonic evolutions, hydrocarbonrich depression and different intensity in tectonic activities. Low amplitude uplifted structure zones in the postrift depression of the sea shelf are the major favorable exploration targets for accumulation of high abundance mediumlarge oil-gas fields.

Key words: tectonic evolution, oil and gas distribution features, play, main controlling factors, Sakhalin, Russian Far East