摘要
水下分流河道是浅水三角洲沉积主要的砂体类型之一,但受砂体规模限制,如何在非密井网区对水下分流复合河道内部单一河道砂体进行表征,是目前开发地质研究中亟待解决的难点之一。以乾安油田高台子油层为例,采用井震结合的手段对目的层水下分流复合河道内单一河道砂体展开划分与识别。研究表明,水下分流复合河道内单一河道砂体侧向叠置关系可划分为切叠式、接触式和孤立式3大类,分别与单边侧向叠加、多边侧向叠加、厚度差异、厚—薄—厚、河间砂沉积型和河间泥沉积型6类测井—地质识别标志相对应;根据密井网区测井资料建立6类识别标志的实际地质模型,并进一步通过正演模拟建立6种单一河道组合正演模型,各种单一河道组合的连接部位的地震响应特征分别为"能量不变、波峰错动、波谷错位"、"能量不变、波形下错"、"能量减弱、波形拉长、上移"、"能量不变、单峰上移"、"能量减弱、视厚度增加、边界错动"、"能量很弱、出现复波";由密井网区单一河道砂体划分结果拟合得到研究区单一水下分流河道砂体宽/厚比经验公式,在此指导下,通过寻找与已建立正演模型特征相符的井间地震响应,完成了稀疏井网区水下分流复合河道内单一河道砂体的识别。
Subaqueous distributary channel is one of the major sand body types in shallow water delta facies,but limited by its size.How to characterize the single channel sand body in the compound channel sand bodies becomes a difficulty in the development geology research now.Taking the Gaotaizi oil layer in Qian＇an Oilfield as an example,combined with well logs and seismic data,the single channel sand body in the subaqueous distributary compound sand bodies of the target layer is divided and recognized.The research shows that the lateral spatial overlay relationship between the single channel sand bodies in the compound channel sand bodies can be divided into three types,i.e.,mutual overlay style,contact style and isolation style.They are respectively corresponded to six log-geology recognition remarks,i.e.,one-sided lateral overlay type,both-sided lateral overlay type,thickness difference type,thick-thin-thick type,sand deposit between channels type and mud deposit between channels type.According to the log data in the high density well area,practical geology model of six recognition remarks is established,then single channel composite forward model corresponding to each geology model has been built through seismic forward simulation.Seismic response characteristics of the joint point in each forward model is＂energy unchanged,peak shift,trough dislocation＂,＂energy unchanged,waveform down shift＂,＂energy reduced,waveform stretch,up shift＂,＂energy unchanged,single peak move up＂,＂energy reduced,visual thickness increased,boundary wave peak shift＂,and＂low energy,complex wave emerged＂.The empirical formula of sand width/thickness ratio of the single subaqueous distributary channel sand body is fitted by the result of single channel sand division in the high density well area.With this guidance and looking for the similar seismic response characteristics between wells in the practical seismic profiles with the established forward models,the recognition of single channel sand body in the subaqueous distributary channel compound sand bodies in the low density well area is accomplished.
作者
王俊
高银山
王洪君
王新星
鲍志东
张红静
Wang Jun;Gao Yin-shan;Wang Hong-iun;Wang Xin-xing;Bao Zhi-dong;Zhang Hong-iing(College of Geoscience,China University of Petroleum（Beijing）,Beijing 102249,China;5^t Oil Production Plant,Changqing Oilfield Company of CNPC,Xi＇an 710200,China;Geophysical Technology Research Center,BGP Inc.of CNPC,Zhuozhou 072751,China)
出处
《天然气地球科学》
EI
CAS
CSCD
北大核心
2018年第9期1310-1322,共13页
Natural Gas Geoscience
基金
"十二五"国家科技重大专项项目(编号:2011ZX05004-004-007)
中国石油天然气股份有限公司重大科技专项项目(编号:2013E-0501)联合资助
关键词
单一水下分流河道
正演模拟
井震结合
青山口组
乾安地区
松辽盆地
Single subaqueous distributary channel
Forward simulation
Identification marks of logging and seismic
Qingshankou Formation
Qian＇an area
Songliao Basin
