珠江口盆地B油田储量参数概率分布

Probability distribution of reservoir parameters in the B oil field, Pearl River Mouth Basin

涂乙 杨娇 王秀玲 万钧

Tu Yi Yang Jiao Wang Xiuling Wan Jun

中海石油(中国)有限公司 深圳分公司, 广东 深圳 518000

Shenzhen Branch, CNOOC (China) Ltd., Shenzhen, Guangdong 518000, China

针对珠江口盆地某油田圈闭面积大、构造不规则且井资料少等问题，为了准确获取储量大小、潜力和风险，采用概率法进行储量快速评估是目前最为有效的方法。以B油田Z5油藏为例，考虑到该油藏构造两翼较陡以及中间过渡带较长且井控程度较低，采用面积-厚度-形状因子法构建岩石体积模型，提出根据油藏形状分为N个模块，分模块精细刻画Z5油藏形态，降低构造形态不规则对储量的影响。其中有效厚度、孔隙度采用对数正态分布，含油饱和度采用正态分布，含油面积、体积系数和原油密度均采用单值分布模型，建立各参数概率分布以及储量概率分布模型。结果表明，概算法Pmean储量结果与该油藏确定性方法计算储量规模接近，两者误差不到4%。结合地质参数对储量大小敏感性分析结果，可指导油藏部门进行储量敏感性、经济性、风险和潜力的深入研究，为开发方案与决策的制定提供依据。

A block of the Pearl River Mouth Basin has a large trap area, irregular structure and limited well data and thus to get accurate reserve size, potential and risk, the probability method is most effective for rapid reserve assessment. The Z5 reservoir in the B oil field was taken as an example. Considering steep wings, long middle transition zone and the low level of well control, an area/thickness/shape factor method was used to construct a physical model of bulk-volume rock. N modules were divided according to the distribution form of reservoir. The form of Z5 reservoir was precisely described according to each module, which could reduce the influence of irregular structural form on reserve. Logarithmic normal distribution was used to analyze effective thickness and porosity. Normal distribution was chosen for oil saturation. A single value distribution model was adopted to study oil-bearing area, volume coefficient and crude oil density. The probability distribution of various reserve parameters and a reserve probability distribution model were established. The results show that the Pmean reserves of the approximate method were close to those of the deterministic method, and the error between them was less than 4%. Combined with reserve sensitivity analysis results of the geological parameters, the study could guide the studies of reserve sensitivity, economics, risk and potential, and provide a theoretical basis for development plans and decisions.

国家科技重大专项“南海东部海域大中型油气田地质特征”（2011ZX05023-006-03）资助。

https://doi.org/10.11781/sysydz201704573