Reservoirs Patterns and Key Controlling Factors of the Lenghu Oil & Gas Field in the Qaidam Basin, Northwestern China

Abstract

The Lenghu area is one of the most crucial tectonic belts for oil and gas exploration in the Qaidam Basin. However, reservoir distribution and the factors controlling petroleum accumulation in this area have not been studied in detail. In this paper, the structural characteristics and controlling factors of oil and gas accumulation in the Lenghu belt are investigated based on seismic profiles combined with drilling logs and microphotographs data. Results indicate that the Lenghu belt has thick source rocks and has preserved hydrocarbon generation conditions. Moreover, structural characteristics and lithology are the key factors controlling the reservoir distribution. The production of oil and gas layers are mainly distributed in high structural points and weak stress zones. The fracture zones and the weak stress zones are the potential places for the distribution of oil and gas reservoirs.

Keywords

Lenghu belt / reservoir patterns / controlling factor / potential distribution zones

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