基于反演多参数体约束地质建模的水平井预警技术——以玛湖地区致密砂砾岩油藏为例  

Early warning technology by geological modeling based on multiparameter constrained inversion for horizontal wells:A case of tight conglomerate reservoirs in Mahu area

作　　者：李晓梅[1] 李洲[1] 邓振龙 宋平[1] 楼仁贵[1] 秦明[1] LI Xiaomei;LI Zhou;DENG Zhenlong;SONG Ping;LOU Rengui;QIN Ming(Research Institute of Exploration and Development,Xinjiang Oilfield Company,PetroChina,Karamay,Xinjiang,834000,China)

机构地区：[1]中国石油新疆油田分公司勘探开发研究院,新疆克拉玛依834000

出　　处：《油气地质与采收率》2021年第5期57-63,共7页Petroleum Geology and Recovery Efficiency

基　　金：国家科技重大专项“准噶尔盆地致密油开发示范工程”(2017ZX05070-002)。

摘　　要：针对玛湖地区致密砂砾岩油藏储层横向变化快、井间构造和储层预测难度大、优质储层钻遇率低等问题,采用反演多参数体约束地质建模,实现对优质储层三维空间分布的刻画,为水平井预警调控提供重要的依据。通过在油层之上建立预警标志层,根据标志层实钻数据更新局部速度场、构造和地质模型,提前预警靶点深度和水平段倾角关键参数变化,并根据井轨迹方向岩性韵律预测结果和随钻电阻率变化规律,及时进行水平段出层风险预警,以达到提高入靶精度和优质储层钻遇率的目标。当钻进位置位于正韵律区,电阻率下降反映顶切,有顶出的风险,需要进行预警并采取降斜措施;当钻进位置位于反韵律区,电阻率下降较快,有底出的风险,需要进行预警并采取增斜措施。玛湖地区应用效果表明,基于反演多参数体约束地质建模的水平井预警技术使油层钻遇率提高了7.4%,钻井周期缩短了8.7%。Due to the fast lateral changes of tight conglomerate reservoirs in Mahu area,difficult prediction of the interwell structures and reservoirs,and low drilling ratios of high-quality reservoirs,the geological modeling based on multiparameter constrained inversion was employed to characterize the three-dimensional spatial distribution of high-quality reservoirs,providing a solid basis for early warning and control of horizontal wells.The early-warning marker bed was established on the oil pay,and the local velocity field and structure as well as the geological model were updated according to the actual drilling data of the marker bed.The changes in key parameters,including target depth and horizontal-section dip angles,were forewarned.According to the prediction results of lithological rhythms along the well trajectory and the variation in resistivity while drilling,the early risk warning of drilling out of high-quality reservoirs in horizontal sections was carried out in time to improve the accuracy of target entry and drilling ratios of for high-quality reservoirs.When the positive rhythm area was drilled,the resistivity drop reflected the topcut,at a risk of top drill-out,which required early warning and a smaller hole angle;when the anti-rhythm area was drilled,the resistivity declined rapidly,at a risk of bottom drill-out,which demanded early warning and a larger hole angle.The application results in Mahu area demonstrate that the early warning technology by geological modeling based on multiparameter constrained inversion for horizontal wells enhances the drilling ratios of oil pays by 7.4%and cut the drilling period by 8.7%.

关 键 词：致密砂砾岩油藏 地质建模 水平井预警 随钻电阻率 玛湖地区 

分 类 号：TE243.1[石油与天然气工程—油气井工程]