摘要
根据区域地震资料研究塔里木盆地塔东凸起西部中上奥陶统层序地层格架及沉积演化,在中上奥陶统识别出了2个地震层序,发现了叠置的丘状前积反射地震单元,综合岩心观察、岩屑录井和薄片资料,确认为海底扇沉积体.海底扇沉积主要由块状砂、砾岩,递变层理砂岩,平行层理砂岩,砂纹层理粉砂岩,变形或包卷层理粉砂岩,水平层理泥质粉砂岩或粉砂质泥岩,块状或递变的粉砂质泥岩和泥岩等岩相组成,形成于中扇和外扇环境,物源来自研究区南部的岛弧带.海底扇的发现对于塔东凸起乃至整个塔里木盆地中上奥陶统油气勘探具有重要意义.
Middle-Upper Ordovician sequence stratigraphy and sedimentary evolution are studied based on the interpretation of regional seismic data in west Tadong uplift, Tarim basin, Northwest China. Two seismic sequences are identified in the Middle-Upper Ordovician, and a group of seismic reflection units with mounded geometry and clinoforrns are confirmed as stacked submarine fan deposits calibrated by cores and lithological logs. The submarine fan deposits mainly consist of seven types of lithofacies, which are massive conglomerates and sandstones, normal-graded sandstones and siltstones, parallel-bedded sandstones and siltstones, rippled siltstones, convolute siltstones, horizontal-laminated silty shales, and massive or graded shales, respectively. The submarine fans were sourced from the Middle-Late Ordovician island arcs located to the south of our study area. The findings of this study are significant to hydrocarbon exploration in the Tarim basin.
出处
《地球科学(中国地质大学学报)》
EI
CAS
CSCD
北大核心
2006年第3期366-371,共6页
Earth Science-Journal of China University of Geosciences
基金
国家重点基础研究发展规划项目(No.G2000078501).
关键词
地震解释
层序
海底扇
浊流沉积
奥陶纪
塔里木盆地.
seismic interpretation
sequence
submarine fan
turbidite
Ordovician
Tarim basin.