塔河缝洞型油藏单井含水变化类型定量评价

Quantitative Evaluation of Single Well’s Water Breakthrough Types in the Tahe Fractured-vuggy Reservoir

塔河油田的储集体有溶洞型、裂缝型、裂缝溶洞型、溶洞裂缝型和缝孔型,导致实际生产中经常出现油井暴性水淹、油井停喷、产量递降、压水锥无效等复杂难题。可以通过分析水驱曲线的变化来评价不同储层类型或工程措施对生产的影响情况,前人通常采用两种方法来评价油井见水快慢程度:(1)通过生产曲线形态定性地表征油井见水快慢,将油井划分为缓慢出水型、含水突发上升型和间歇出水型等;(2)简单地用两个时刻含水率之差来评价单井或井与井的含水上升速度。基于评价油井见水快慢的传统方法的缺陷,本文提出一种新型双水驱曲线来分析油井动态生产情况,并用一种新的评价指标——水油比(拟合直线斜率k)来定量评价油井见水快慢,并最终对塔河四区S48单元井的含水变化进行了系统分类。

The reservoir types in Tahe oilfield consist of cave, fracture, crack-cave, cave-fracture and fracture-vuggy, which makes the problems complicated in the actual production, such as violent water flooding, stop ping blowout, production decline and invalid coning water. We can evaluate the effect of different reservoir types or engineering measures on production through the analysis of water flooding curve changes. The following two methods of water breakthrough speed were commonly evaluated： 1） evaluating water breakthrough speed quantitively according to the shape of production curve, and dividing oil wells into types of slow rising, sudden rising and, water and intermittent rising etc. 2） evaluating water breakthrough speed of single well or wells simplely using the watercuts in two points of time. Based on the disadvantage of the conventional methods, this paper makes a careful analysis in oil production curve, and forms a new dual water curves to analyze the well＇s dynamic production. By using a new evaluation parameter-water/oil ration（the slope of the fitting line, k）, we evaluate the speed of water breakthrough quantitively. At last, the authors classified the water breakthrough types of the wells in No.4 block, in Tahe Oilfield.