Hydrocarbon Systems and Assessment of The Probability of Discovery of Oil and Gas Accumulations in The Tatar Strait of The Sea of Japan

Abstract

Summary Numerical basin modeling of the Tatar Strait of the Sea of ​​Japan of the Tatar oil and gas region made it possible to identify up to 10 generation-accumulation hydrocarbon systems, represented to varying degrees in four stratigraphic intervals: Eocene-Oligocene, Oligocene-Miocene, Middle-Upper Miocene and Upper Miocene. Eocene-Oligocene hydrocarbon systems occupy the largest area of ​​the Tatar oil and gas bearing area and include large foci of oil and gas generation. The largest focus is associated with the South Tatar hydrocarbon system, the level of maturity of organic matter (OM), which corresponds to the “gas window” or exceeds it. The largest hydrocarbon systems of the Oligocene-Lower Miocene (Uglegorsk) interval are the North Tatar, Central Japan and South Tatar. In most of the areas occupied by them, the maturity of organic matter corresponds to the stage of predominant gas generation. The generation, migration and accumulation of hydrocarbons in the hydrocarbon systems of this interval began in the period from the end of the Early Miocene to the middle - second half of the Middle Miocene. The hydrocarbon systems of the Middle-Upper Miocene - Uglegorsk-Kurasian and Kurasi-Maruyamsky, in accordance with the modeling results, were formed in the conditions of a gradually deepening sea basin. The processes of generation, migration and accumulation of hydrocarbons in these systems began locally in the middle of the Miocene, and in main volumes - at the boundary of the Miocene and Pliocene, or somewhat later.