基准面旋回格架内储层发育类型及其特征——以珠江口盆地LF13井区珠江组为例

The Development Types and the Characteristics of the Reservoir Within Base-level Cycle Framework——A Case Study of the Zhujiang Formation in LF13 Well Block of Pearl River Mouth Basin

通过测井、岩心、地震等资料综合分析,将珠江口盆地LF13井区珠江组划分为12个中期基准面旋回和5个长期基准面旋回,与经典层序地层体系的三级层序相对应。以此为基础,结合该井区储集层在单井和连井上的孔隙度、渗透率以及泥质含量等的变化,分析了基准面旋回格架内的砂体发育特征。长期基准面下降末期和上升初期可容纳空间低,沉积物供给量大,为厚层连片砂体发育的有利位置,其物性相对较好;长期基准面上升阶段偶见砂体发育,沉积物供给相对不足而可容纳空间极高,沉积砂体物性相对较差,连通性差,且泥质含量偏高。最终,综合砂体物性、基准面旋回、沉积相和成藏资料,提出在长期基准面上升初期-中期寻找岩性地层圈闭的有利的观点。

According to the log,core and the seismic data,the Zhujiang Formation of Well LF13 in Pearl River Basin was divided into 12 mid-term base level cycles and 5 long-term base level cycles which equal to the third-order sequence of the classic sequence stratigraphy system.Basis on the results mentioned above,in combination with the change of the porosity,permeability and the shale content of single well and connecting-well,the characteristics of the development of sand body within the base level cycle framework are analyzed.Low accommodation space which was the advanced position for the development of thick layer linked sand because of the sufficient supplies of the sediments and the good physical properties developed in the end period of the decrease of long-term base level and at very beginning of the increase of the long-term base level.In the increase period of base level,the sand of which the physical properties and the connectivity is poor occasionally,and the sediment supplying is relatively insufficient in spite of the high accommodation space.In combination with the sand properties,base level,sedimentary facies and the reservoir forming information,it is suggested that the beginning and middle periods of the increased base level are the favorable period for the prospecting of lithologic-stratigraphic trap.