地震沉积学在BZ19-4油田中的应用

Application of seismic sedimentology in BZ19-4 Oilfield

地震沉积学主要利用三维地震资料和现代地球物理技术,结合钻井资料进行沉积体系、沉积相平面展布以及沉积演化研究。海上油田钻井资料少,一般利用地震沉积学方法进行沉积相方面的研究。文中在渤海南部海域BZ19-4油田新近系明化镇组下段进行了地震沉积学应用研究,即利用井震结合进行层序划分及地层对比,根据对比结果的小层厚度发育情况选择合理的切片时窗,使用90°相位移资料进行地层切片,研究系列地层切片,同时结合钻井信息进行地质解释。研究结果表明,研究区发育浅水三角洲沉积砂体,纵向上经历了Ⅲ,Ⅳ油组窄河道型砂体到Ⅰ,Ⅱ油组朵叶状三角洲砂体的沉积演化。油田开发过程中,针对不同油组砂体发育特征,可采取不同的开发策略。

Seismic sedimentology can be used to study sedimentary system, plane distribution of sedimentary facies and sedimentary evolution through the use of 3D seismie data and modem geophysical technology（90° phase control and strata sliee）, eombined with drilling data. Because the drilling date lack for offshore oilfield, seismic sedimentology method can be used to study sedimentary syslems. In BZ19-4 Oilfield which is located in the southern part of Bohai Sea, we use the melhod to conduct the application study of seismic sedimentology in I^wer Minghuazhan Formation. That is the sequence division and strala correlation can be eondueted by lhe well-seismic eombination. Aceording to the layer thicknes, we select the reasonable slice window and make the slice through the use 90° phase shift seismic data. Then, strata slice is studied, and geological inteq）retatiun is completed through the combination of drilling data at the same time. Study results show that the shallow water delta sedimentary, sandbodies developed in the study area and they underwent the sedimentary evolution from narrow channel sandbody in oil measures Ⅲ and Ⅳ to lobati（m deha sandbody in oil measures Ⅰ and Ⅱ. Different development strategies can be adopted aiming at the sandbody development feature of different oil measures during oilfield development.