摘要
针对乌兰花凹陷安山岩储层具有低孔特低渗、天然裂缝发育、高杨氏模量、低泊松比和脆性强等特点,压裂中如何在控制滤失的同时充分利用天然裂缝等弱面,是裂缝性储层压裂工艺和改造工作液面对的难题。以储层特点及改造难点为出发点,借鉴非常规油气藏体积改造中"疏与堵"相结合的天然裂缝处理模式,缩小基质—裂缝流动距离,提高基质贡献程度。依据室内实验和现场实践,优选出0.25%低浓度瓜尔胶低伤害压裂液体系,采用线性胶与冻胶相结合的复合压裂工艺技术,前期利用低黏线性胶起裂,以实现缝高控制和沟通天然裂缝;后期采用组合粒径支撑剂段塞注入技术,实现高导流、控缝高的改造目标。该技术已应用在兰42井安山岩裂缝储层改造中,获工业油流,井温测试结果显示裂缝高度控制较好,取得较好的应用效果,对乌兰花凹陷安山岩勘探开发具有重要的借鉴意义。
Wulanhua sunken andesite reservoirs feature in low porosity,ultra-low permeability,well developed natural fractures,high Young’ s modulus,low Poison’ s ratio,and high brittleness.To take full advantage of nature fractures while controlling filtration is difficult for fracturing process and working fluid transform in fractured reservoirs.Taking reservoir features and transform difficulties as a starting point,we learned from the natural fracture treatment modes by combining ways of dredging and blocking during reservoir volume stimulation of unconventional oil and gas reservoirs,reduced the matrix-fracture flow distance,and enhance the contribution of matrix.Based on lab experiment and field practice,we chose the 0.25%low-concentration guar-based fracturing fluid,adopted the complex fracturing technology integrating linear glue and gel.At earlier stage,we used linear glue of low viscosity to initiate fracturing,so as to fulfill fracture height control and natural fractures connection.At later stage,we utilized the technology of combined particle size proppant with plug pumping to achieve the goal of high flow conductivity and fracture height control.We had applied to Andesite fracture reservoir stimulation of Well Lan 42 and got industrial oil flow.And the well temperature test results showed that the fracture height was controlled well.It could be good reference to andesite exploration and development in Wulahua Sag.and hybrid fracturing technology,which can achieve high conductivity and well fracture height control.The above research results are applied in Lan42 well,after stimulation the test production reached 3.2m /d,which achieved better effect of stimulation results,and have great significance for the breakthrough of Wulanhua sunken exploration and development.
出处
《非常规油气》
2016年第1期77-81,共5页
Unconventional Oil & Gas
基金
中国石油天然气股份有限公司科技重大专项(2014B-1202,2014E-35)
关键词
安山岩
裂缝性储层
压裂
低浓度
控制裂缝高度
andesite
fractured reservoir
fracturing
low concentration
fracture height control
