The Prospecting Advantageous On Chang8 Reservoir Of Yanchang Formation In Zhangjiawan Area, Zhiluo Oil Field.

According to the petroleum geology, sedimentary geology?logging geology?reservoir geology, geochemistry and so on as a guide. Based on the experimental test technology, with the use of the field outcrop, well drilling, logging and production performance data. As the beginning of studying depositional-facies and sand distribution, making a comprehensively analysis of the character of reservoir, diagenesis study, reservoir quality, microscopic pore structure, relationship of oil nature and macroscopic heterogeneity?combine with the character of source rock which controls the distribution of hydrocarbon in a certain degree, and finally point out the advantageous zones in this area.The study shows that the Chang8 formation has a gentle structure is low and slow latitudinal nose-shaped uplifts based on west-east dip monocline. The front-delta deposition developed mainly subaqueous distributary channel?the two wings of river microfacies and subaqueous interdistributary embayment. The main type of sandstone is minute and mintueness granular feldspathic litharenite and lithicarkose. The dominating pore types are feldspar dissolution and inter-granular pore. Because of poor physical property, Chang8 belongs to extremely lower porosity and permeability reservoir. On the basis of regular physical data, the secondary is Chang S reservoir, the average porosity is 10.02% and the average permeability is 0.3 Im D. The mainly experienced diagenesis are compaction, pressure solution, cementation, metasomatism and dissolution. In the underlying of Chang8 is Chang9, which has a large distribution and thickness and is the main source rocks for Chang8 reservoir. Combine with the test data and analysis, the main conclusions of control the distribution of oil and gas are the character of sediment, reservoir quality, structure influence and the distribution of source rock. Comprehensive oil well data?studying the dominate formation Chang8— where is the advantage exploration area which include four areas of the first type?two areas of the second type and two areas of the third type, which provides credible geology reference for further exploration and development.