Study Of Hydrocarbon Accumulation Model In Zhen-jing Block

The study of hydrocarbon accumulation is one of the important contents in the theory of petroleum geology, it is mainly analyzed the characteristics of reservoir, the formation process of oil and gas,and the regularities of distribution. Hydrocarbon reservoir study including static description and hydrocarbon accumulation mechanism and process analysis. The static characteristics of reservoir description mainly from the reservoir type, reservoir description cover etc. Characteristics of reservoir Hydrocarbon accumulation mechanism and process analysis with various analysis method is mainly studied and hydrocarbon accumulation periods, including the process of hydrocarbon generation, migration, accumulation and preservation and destroy all links.This article selects the Zhen-Jing block of as the research target,which is located in southwest part of Eordos basin. In this block of geological factors (hydrocarbon source rocks, reservoir, cover and conducting layer) and effect (hydrocarbon source rocks, thermal evolution process and hydrocarbon-discharging history, hydrocarbon migration, trap forming process, the process of hydrocarbon accumulation process) is analyzed and described. Through HH1Well for burial history and fluid inclusions in the analysis, the second section’s hydrocarbon source rocks of Yanchang group had achieve hydrocarbon-generating threshold in later Jurassic-early cretaceous (142Ma dating); the third section’s achieved the threshold in the early cretaceous (dating131Ma). The hydrocarbon source rock of Chang7has two generarion and expulsion peaks:(1), late Jurassic,the hydrocarbon source rock of Chang7began to source. Due to the end of late Jurassic stratum, makes the hydrocarbon source rocks thermal evolution process terminates, bore limited hydrocarbon.(2) in the early cretaceous, stratigraphic sedimentation, again hydrocarbon source rocks began to enter life, and in the early so late cretaceous to achieve maximum hydrocarbon-generating period. The oil and gas reservoirs and generated through cracks, unconformity in overpressure and buoyancy driven migration to extend, in yanan depositional period that has formed in the trap accumulation. According to the formation of the abnormal formation pressure (region distribution and diagenesis, reservoir formation conditions and sealing system, can be prolonged group-yanan groups reservoir reservoiring dynamics mechanism is divided into three types:Chang8for the reservoir pressure closed reservoiring dynamics system, diagenesis, corresponding to the continuous buried diagenetic system, Chang4+5&Chang6reservoir as part of the atmospheric upper allo-source semi-open enclosed dynamic system, diagenesis, corresponding to the middle open type diagenetic system, Yanan is half open source is normal accumulation dynamics system, diagenesis, corresponding to the long-term shallow open type diagenetic system. For the reservoir type, Chang8&Chang6should be sorted the lithologic reservoir. While, the Yan’an group’s reservoir is classified structural reservoirs. On the basis of the above analysis, Summarized the hydrocarbon accumulation model about Zhen-Jing block.