塔里木盆地塔东地区中—上奥陶统海底扇浊积岩层序地层格架及沉积特征

塔东地区是塔里木盆地重要的油气资源战略接替区域之一。在剖面、测井和岩心资料的基础上,以Cross的高分辨率层序地层学理论为指导,对区内中—上奥陶统海底扇相浊积岩进行了初步的层序地层分析,识别出了6个三级层序,并建立了横向连井层序地层对比格架,揭示了地层的时空展布规律。在对海底扇相沉积特征研究的基础上,首次以三级层序为单位勾绘了6期海底扇扇体形态的平面展布图,分析了各期扇体的平面展布特征;最后,依据扇体形态,结合其岩性特征和重矿物分析,对海底扇的物源方向进行了初步的探讨,得出该区海底扇物源应来自北部的库鲁克塔格地区,研究成果为本区今后的油气勘探工作提供了依据。

SEQUENCE STRATIGRAPHY AND SEDIMENTARY CHARACTERS OF SUBMARINE FAN OF MIDDLE-UPPER ORDOVICIAN IN TADONG AREA,THE TARIM BASIN

The Tadong area is one of important oil and gas resource potential exploration regions in the Tarim Basin.The research extent on the turbidite of Middle?-Upper Ordovician submarine fan in the area is low. Guided under the theory of high-resolution sequence stratigraphy and based on the sections, well logs and cores,the primary research of sequence stratigraphy about the turbidite of the submarine fan of Middle?-Upper Ordovician is done, and six interfaces of third-order sequences are identified.Lateral stratigraphy comparison frame cross wells is established to reveal time and space distribution of stratigraphy.Combined with the analysis of the sedimentary characters of the submarine fan and firstly by regarding the third-order sequence as primary units,the tabulate graphics of six periodic submarine fan shapes are constructed and the fan's plane distribution of each period is studied.Finally,based on the fan shapes and linked with the lithology characters of the submarine fas,and combined with the analysis of heavy minerals,the primary discussion about the direction of material supply of the submarine fan is made and the material supply is from Kuluketage region in the north.This paper aims at providing evidence for further exploration in the region.