马58H致密油藏水平井分段多簇射孔压裂技术

马58H井是位于三塘湖盆地马朗凹陷马中地层岩性圈闭的水平探井,属致密凝灰岩油藏,具有高孔低渗、小孔喉、非均质性强的特点,水平井段长804 m。为解决该井压裂作业存在的难题,开展了致密油藏水平井分段压裂技术研究。针对低温井压裂液快速破胶难及施工后对致密油储层的伤害问题,研制出配套的超低浓度、低伤害复合压裂液体系,并通过对裂缝条数、裂缝长度、裂缝导流能力的优化、铺砂浓度与导流能力关系优化、簇间距及孔数优化,采用速钻桥塞分段多簇射孔压裂工艺,顺利完成了该井压裂施工。马58H井分段压裂施工总液量7 755.9 m3,总砂量566.3 m3,最高排量11.2 m3/min,压裂后获得日产131 m3的高产油流,为吐哈油田三塘湖致密油高效开发动用探索了一条新途径。

Staged multi-cluster perforation fracturing technology for horizontal Well Ma-58H in tight reservoir

Ma-58H is a horizontal exploratory well in Mazhong stratigraphic and lithologic trap in Malang Depression in Santanghu Basin. It is tight tuff limestone reservoir, characterized by high porosity and low permeability, small throat and high heterogeneity. The length of horizontal section is 804 m. In order to tackle the difficulties in fracturing operation in this well, research was conducted on staged fracturing technique in horizontal wells in tight reservoirs. In line with difficulty in rapid gel breaking for fracturing fluid in low temperature wells and damage to tight reservoir after fracturing, a compound fracturing fluid system of ultra-low density and low damage was developed, and through optimization of fracture numbers, fracture lengths and fracture conductivity, optimization of the relation between proppant density and conductivity and optimization of cluster spacing and hole numbers, the fracturing job was successfully completed in this well using fast drilling of bridge plug and staged multi-cluster perforation and fracturing technology. Total frac fluid used in staged fracturing of Ma-58H Well was 7 755.9 m3, total sand consumption was 566.3 m3 , the maximum displacement was 11.2 m3/min, and the daily oil production after fracturing was 131 m3, opening up a new approach for effective development of Santanghu tight reservoirs in Tuha Oilfield.