塔河油田高精度三维地震采集参数优化研究

Optimization on the high-precision 3D seismic acquisition parameters in Tahe Oilfield

塔河油田以奥陶系缝洞型储层为主,高精度三维地震勘探技术是提高该区小尺度缝洞体识别能力的重要手段。通过采集参数优化来降低高精度三维勘探成本,对于塔河油田勘探开发具有非常重要的意义。利用塔河油田现有高精度三维采集试验区采用可细分面元观测系统采集的资料,进行观测系统退化试验,按照相同面元尺寸不同覆盖次数、相同覆盖次数不同面元尺寸,将原始观测系统退化成若干子观测系统,分别抽取相应的资料进行叠加、叠后偏移和叠前偏移处理,从信噪比、分辨率、"串珠"反射数量与清晰度以及河道刻画等方面对不同子观测系统资料的处理结果进行评价。综合勘探成本与奥陶系缝洞型储层的预测识别能力之间的关系,提出了该区高精度三维地震勘探的关键采集参数建议,给出了应用该建议参数采集的相邻区块资料与试验区资料的效果对比。

Ordovician fracture-cave reservoirs are developed in Tahe Oilfield,high-precision 3D seismic exploration is an important means to improve the identification ability on the small-scale fracture-cave bodies.It is significant to save the cost of high-precision 3D exploration through acquisition parameters optimization.The bins of the high-precision 3D geometry for testing can be subdivided in Tahe Oilfield.Therefore,degradation test is carried out to divide the original geometry into several sub-geometries,including same bin size ＆ different folds and same folds ＆ different bin size.With stack,poststack migration and prestack migration,we evaluate the processing effect of the sub-geometries data from the aspects such as signal-to-noise ratio,resolution,number and clearness of “string” reflections,characterization on channels.By balancing the relationship between exploration cost and the identification ability on the Ordovician fracture-cave reservoirs,we proposed suggestions on key acquisition parameters for the high-precision 3D seismic exploration and displayed the acquisition effect acquired by the suggested parameters in a neighboring area.