摘要
庙西南凸起蓬莱A构造区馆陶组有良好油气发现,但储层厚度多小于5 m,难以被精确识别刻画。以薄层砂体为研究对象,综合地震、测井、钻井岩心、古生物等基础资料,明确研究区馆陶组沉积时期受北东向物源供给沉积,发育河流-浅水三角洲相。基于90°相位化处理确定砂体地震响应特征;分频解释处理判断相对等时地震同相轴,构建馆陶组高频层序地层格架(三级层序SQ1-3),优选60Hz地震数据体进行地层切片划分;地层切片高精度沉积学解释揭示研究区馆陶组SQ1层序至SQ3层序依次发育河流-席状化浅水三角洲-朵叶状浅水三角洲-水下河道型浅水三角洲。其中SQ1层序中河道砂体以及SQ2-3层序中浅水三角洲前缘砂体皆为有利储层。此次研究丰富发展了渤海海域河流-浅水三角洲相中地震沉积学在砂体预测中的研究成果。
The Penglai A structure area in the Miaoxinan uplift had good drilling show of oil and gas in the Guantao formation,but reservoir sands with the thickness less than 5 meters could not be resolved and interpreted precisely.Recognition that the source direction in the sedimentary period of Guantao formation is northeast,fluvial to shallow water delta facies were developed which was made by comprehensive utilization of drilling cores,the data of sporopollen and algae,logging and 3-D seismic data.90°phasing adjusted seismic wavelet phase to-90°to tie seismic events to lithology.Frequency division was used to interpret,treat and judge phase axis following relative geologic time surfaces to establish high-frequency,sequence stratigraphic framework and optimized 60 Hz dominant frequency seismic data for stratal slicing.Stratal slicing made from the 3-D seismic volume revealed better facies information on the relative geologic time surfaces.With the interpretation of sand body depositional features displayed on each sequence stratal slice,it could be found that sedimentary evolution process in the study area was divided into four stages:fluvial facies stage,sheet-like shallow water delta stage,lobate shallow water delta stage and distributary channel shallow water delta stage.And it also could be found that the sand body mainly developed horizontally in the north of the study area,and the position of fluvial channels and shallow water delta front provided good areas for oil and gas exploration.This study case proved that the method of seismic sedimentology is suitable for thin sandstone reservoir prediction in Bohai basin.
作者
付鑫
杜晓峰
官大勇
李瑾
李晓辉
Fu Xin;Du Xiaofeng;Guan Dayong;Li Jin;Li Xiaohui(Tianjin Branch of China National Offshore Oil Corporation Limited,Tianjin 300452,China)
出处
《地质科技通报》
CAS
CSCD
北大核心
2021年第3期96-108,共13页
Bulletin of Geological Science and Technology
基金
“十三五”国家重大专项(2016ZX05024-003)。
关键词
地震沉积学
渤海海域
河流-浅水三角洲相
储层预测
馆陶组
seismic sedimentology
Bohai basin
fluvial to shallow water delta facies
reservoir prediction
Guantao formation
