东濮凹陷挥发油特性及勘探方向

东濮凹陷现已查明的文 72、文 88、文 1 3东等 3个挥发油油藏的流体性质明显不同于其它油气藏 ,不仅具有原始溶解气油比高、体积系数高、饱和压力高、饱和油压缩系数高、气体平均溶解系数高、收缩率高和饱和油密度低、流体黏度低的特性 ,而且在化学成分、PVT特征、体积收缩特征等方面也很特殊。在形成条件方面与其它油气藏相比也有其特殊性 ,质量好、成熟良高的生油岩是油藏形成的物质基础 ,巨厚的盐膏岩、膏泥岩或泥页岩沉积组合作盖层和侧向封堵是油藏的圈闭条件 ,埋藏深有利于高气油比流体的运移聚集 ,深部地温高有利重烃热裂解为轻烃 ,并能提高油藏的气油比 ,馆陶期以后地层未受构造运动影响 ,是保存油藏的重要条件。阐述该类油藏的开发规律认为 ,东濮凹陷寻找挥发油油藏的主要地区和层位是 :长垣断层下降盘沙三中4— 10 —沙三下 ;文东构造带北部沙三中4— 10 —沙三下1— 4;白庙—桥口构造深层沙三中—沙三下亚段以及刘庄地区沙二下亚段。图 4表 2参 2

The properties of volatile oil and its exploratory direction in Dongpu depression

The fluid properties of Wen72, Wen88 and Wen13 East structures, which have been proven as volatile oil reservoirs, are different from others clearly in Dongpu depression. These three reservoirs not only have the characteristics of "six high and two low" but also are very unique in chemical components, PVT feature, volume shrinkage feature and so on. Compared with other reservoirs, they also have some particularity in formation conditions. The oil source rock with better quality and high maturity is the material basis for their formation; the depositional combination of the massive salt rock, salt mudstone or shale as cap rock and lateral sealing are their trap conditions. The deep burial is of benefit to the migration and accumulation of the fluid with high gas oil ratio. The high geotemperature in deep depth is of benefit to the heavy hydrocarbon cracking into light hydrocarbon and to the improvement of gas oil ratio. It is an important factor to preserve these reservoirs that structure movement after Guantao Period has not affected the formations. This paper demonstrates the development law for the type of reservoir. The authors consider that the main areas and formations to find the volatile oil reservoir in Dongpu depression are the S 3M 4 10 -S 3L in downthrow block of Changyuan Fault, the S 3M 4 10 -S 3L 1 4 in the north part of Wendong structure belt, S 3M-S 3L submembers in the deep zones of Baimiao Qiaokou Structure and the S 2L of Liuzhuang area as well.