鄂尔多斯盆地长7段致密油合理开发方式探讨  

Development modes of Triassic Yanchang Formation Chang 7 Member tight oil in Ordos Basin, NW China

作　　者：李忠兴[1] 屈雪峰[2,3] 刘万涛[2,3] 雷启鸿[2,3] 孙华岭[2,3] 何右安[2,3] 

机构地区：[1]中国石油长庆油田分公司 [2]中国石油长庆油田分公司勘探开发研究院 [3]低渗透油气田勘探开发国家工程实验室

出　　处：《石油勘探与开发》2015年第2期217-221,共5页Petroleum Exploration and Development

基　　金：中国石油天然气股份有限公司重大科技攻关项目(2011E-2602)

摘　　要：鄂尔多斯盆地三叠系延长组长7致密油储集层致密,孔隙结构复杂,孔隙度小,渗透率低,储集层微裂缝发育,地层压力系数低,采用丛式井网超前注水开发单井产量低,难以实现有效动用。以鄂尔多斯盆地A井区长7致密油为例,通过物质平衡理论计算、数值模拟方法研究以及矿场实践数据分析,认为水平井体积压裂后单井产量大幅度提高,但采用直井注水、水平井采油的联合井网开发,水平井见注入水风险大,见水比例达到65%;水平井衰竭式开发地层能量下降快,前期单井产量平稳,生产12个月后单井产量递减大,4个月单井产量累计下降50.3%。由此提出了水平井体积压裂后衰竭式开采,待地层能量不足时,运用注水吞吐采油的开发方式,致密油体积压裂水平井注水吞吐第1周期单井日产油量比吞吐前增加78.3%,注水吞吐采油取得初步效果。The Triassic Yanchang Formation Chang7 Member tight oil reservoir in Ordos Basin, featuring complex pore-throat structures, low porosity, low permeability, rich micro-fractures and low pressure coefficient, is difficult to produce by advanced water-flooding from cluster vertical wells with low individual-well producing rate. With Block A as an example, the material balance calculation, numerical simulation and field practical analysis showed that the horizontal well production would increase significantly using volumetric fracturing. But the well pattern of water injection in vertical wells and oil production in horizontal wells has high risk of injection water breakthrough in horizontal wells, and the proportion of water breakthrough wells reached 65%. In contrast, the formation energy decreased in depletion development with horizontal wells, in which the oil production kept stable in early period, but decreased quickly after 12 months, the cumulative decline of oil rate in 4 months amounted to 50.3%. Therefore, a development scheme of depletion production from volumetric fracturing horizontal wells at first and then water-flooding huff and puff after producing energy is deficient was proposed. Following this scheme, the daily oil rate of single well increased by 78.3% after the first cycle of water huff-and-puff than before the treatment, marking the initial success of the measure.

关 键 词：致密油 体积压裂 开发方式 水平井 数值模拟 注水吞吐 

分 类 号：TE348[石油与天然气工程—油气田开发工程]