摘要
库车坳陷前陆区白垩系巴什基奇克组广泛发育扇三角洲前缘砂体,是天然气富集的有利场所。针对大北气田钻井少、井距大的特点,选取与目的层地质特征相似的典型露头剖面,利用三维激光扫描技术对其进行多方位全覆盖扫描和三维数据采集,并与人工实测地质信息和分析化验资料相结合,借助计算机模拟技术建立三维数字化地质模型,有效揭示扇三角洲前缘砂体构型特征。结果表明:研究区扇三角洲前缘砂体构型样式包括不完全叠拼式、侧拼式和孤立式3种,由于构型样式不同,砂体间连通性存在差异;砂体具有多期水下分流河道垂向叠加、大面积连续分布的特点,且河道砂体中、下部物性比底部和上部好,且以均质的中砂岩和细砂岩为最优;伴有少量河口坝和远砂坝微相沉积,砂体厚度和宽度与厚度比具有较好的负相关性;砂岩含量高,砂体间发育稳定的条带状泥岩,砂体间并非完全连通,层内和层间非均质性较强。
The sandbodies of fan delta front developed widely in Cretaceous Bashenjiqike Formation in the foreland area of Kuqa depression,which are favorable places for natural gas accumulation. In view of the situation of few drillings and large inter-well spacing in a certain gas field,a typical outcrop,which has the similar geological situation with the target stratum,was chosen to be scanned in multi-faceted and full coverage by the holographic laser scanning technology for acquiring three-dimensional data,and then a three-dimensional digital geological model was built through matching the data with the measured geological information and sampling analysis data by computer simulation technology to reveal the sandbody architecture of fan delta front effectively. The results show that the sandbody architecture types of fan delta front in the study area include three types:incomplete stacked stitching type,side stitching type and isolated type,while the sandbody connectivity are very different owing to the architecture differences. The channel sandbodies are presented as multiple underwater distributary channels stacked vertically and distributed widely,where the physical properties of the middle and lower part are better than that of the bottom and the top and the homogeneous medium sandstone and fine sandstone are the best. A few mouth bars and distal bars are also developed with a negative correlation between the sand thickness and width-thickness ratio. The sandstone content of the modeling section is high and there is stable lateral distribution of mudstone interbedded with the sandbodies. The sandbodies are not fully connected with each other and the inner-and interlayer heterogeneity is strong.
出处
《油气地质与采收率》
CAS
CSCD
北大核心
2017年第2期30-37,共8页
Petroleum Geology and Recovery Efficiency
基金
国家科技重大专项"重点前陆冲断带储层改造机制与地质评价"(2016ZX05003-001-002)
国家"973"计划"中国西部叠合盆地深部油气复合成藏机制与富集规律"(2011CB201104)
关键词
数字露头技术
扇三角洲前缘
砂体构型
储层模型
库车坳陷前陆区
digital outcrop technology
fan delta front
sandbody architecture
reservoir model
Kuqa foreland area
