针对目的层埋深大、钻井稀少且分布不均所造成的沉积相研究和砂体预测的难题,以哈萨克斯坦南图尔盖盆地Doshan地区为例,在层序地层学和沉积学研究的基础上,充分挖掘三维地震数据的横向分辨能力,利用90°相位转换、地层切片、分频处理等地震沉积学关键技术,通过单井相标定地层切片属性的实际地质意义,应用纵向关联的多张地层切片,识别出阿克沙布拉克组(SQ8层序)至少发育六期河道,其中SQ8-1旋回内发育两期,为河道发育最广泛、最强烈的时期;SQ8-2旋回内河道稀疏,纵向连续性差;SQ8-3旋回河道分布局限,水体范围缩小,与SQ8-1、SQ8-2相比较具有沉积的继承性特征,反映出水体深度有所变浅,经历了一期以水进为主的水进—水退过程.研究表明,地层切片技术有效地描述了河道的平面几何形态与不连续性,这为本区岩性地层圈闭的描述与预测提供了地质依据.

Taking Doshan area as an example, based on the study of sequence stratigraphy, sedimentology and the lateral resolution of seismic data, this paper characterizes the Akshabulak Formation sedimentary system by using the methods of seismic sedimentology such as stratal slicing, 90° phasing conversion and frequency division. Through calibrating the attributes of strata slice to actual geological significance by combining single well facies with associated stratal slice in vertical, at least 6 periods channels are identified, in which 2 periods are in SQ8-1 Formation that indicate channels developed most widely and intensely; the channels in SQ8-2 Formation are thinning and have poor continuity;the channels in SQ8-3 Formation distribute limited and the water area is shrinking, a main transgressive process is reflected in changing shallow water and sedimentary succession in a transgressive and regressive process compared with SQ8 -1 and SQ8 -2 Formation. The result shows that the stratal slicing technique describes the plane geometry and discontinuity of the channels effectively, and it can be the geological basis for the description and prediction of lithologic stratigraphic traps in this study area.