苏里格气田苏20区块气水分布规律

苏里格气田苏20区块储层非均质性强,气藏气水分布的复杂性严重影响了气田产能建设效果,且随着勘探开发的不断深入,井位部署逐渐由富气区向外扩展,新完钻井投产后效果差,产水严重。因此开展气水分布规律研究已成为提高该区块产建效果的基础。在区域水化学分析、测井气水层识别、区域地质背景综合分析的基础上,对苏20区块气水的分布规律进行综合研究后认为:①气藏气水关系复杂,无统一的气水界面;②研究区垂向上表现为下气上水,下二叠统山1段基本不含水,从下二叠统盒8下亚段2层→盒8下亚段1层→盒8上亚段的地层水逐步增多;③从成藏要素分析,表明苏20区块富水与其生烃强度、构造位置和天然气的运移密切相关;④地层水根据其成因差异可以分为低部位滞留水、透镜状滞留水、孤立透镜体水3种类型,研究区内主要为透镜状滞留水类型。

Gas water distribution pattern in Block 20 of the Sulige Gas Field

The gas productivity construction is severely influenced by the strong heterogeneity of reservoirs and the complexity in gas and water distribution in Block 20 of the Sulige Gas Field. In addition, water production is a serious problem for new gas wells which are emplaced outside sweet spots along with the deepening of exploration and development. Therefore, it is quite necessary for decision makers to understand the gas water distribution in the study area. Based on the regional hydrochemical analysis, logging identification of gas/water layers, and regional geologic background, the gas water distribution pattern in Block 20 is thoroughly studied and the following understandings are obtained. a. Gas water relationship is so complicated that no uniform gas water contact exists. b. Vertically, gas layers underlie water layer. c. The abundance of water in this block is closely related with hydrocarbon generation intensity, structural location, and gas migration. d. Formation water can be classified into 3 genetic types including resident water in structural low, water in isolate lens, and resident water in lens, the last of which is predominant in the study area.