Geochemical characteristics and reservoir formation mechanism of tight oil source rocks in the Yanchang formation
In order to clarify the characteristics and control factors of tight oil reservoir formation in Ordos Basin,based on previous contributions and relevant geological data,combined with indoor experimental simulation,the pore structure characteristics,geochemical characteristics of hydrocarbon source rocks,and reservoir formation mechanism of the Yanchang Formation tight oil reservoir were deeply analyzed.The results showed that the tight oil reservoirs of the Yanchang Formation were mainly composed of lithic feldspathic sandstone and feldspathic lithic sandstone,with pore structures mostly at the micro nano scale.The main source types were organic rich shale and dark mudstone.The organic matter maturity of hydrocarbon source rocks was high,mostly greater than 0.7% .Tight oil reservoirs had excellent hydrocarbon production and expulsion rates,and organic shale accumulated to generate hydrocarbons×1 011 t,dark mudstone could accumulate hydrocarbon 2×1 010 t.The pressurization of hydrocarbon generation provided the main driving force for the continuous charging and accumulation of storage,and there were two charging periods.In addition,carbonate cementation was one of the key factors for reservoir densification.
ordos basindense oilreservoir formation characteristicshydrocarbon source rock
万方数据
维普
