古地理学报2017，Vol.19Issue(6)：935-954,20.DOI:10.7605/gdlxb.2017.06.073
鄂尔多斯盆地东南部上古生界层序地层格架及含气砂体沉积演化特征
Sequence stratigraphic framework and sedimentary evolution characteristics of gas-bearing sandbody in the Upper Paleozoic in southeastern Ordos Basin
摘要
Abstract
The traditional idea of hydrocarbon distribution "oil exists in south and gas in north" of Ordos Basin prevailed for a long time,which is contradiction with the latest study.The recognition on lack of sandbodies in the Upper Paleozoic and weak geological research had been constrained the exploration and exploitation in the southeastern Ordos Basin.Therefore,strengthening geological research on the Benxi Formation to Xiashihezi Formation (coal-bearing strata of the Upper Paleozoic),especially the study of sequence stratigraphy and reservoir sandbody genesis has an important theoretical and practical significance.This paper study sequence stratigraphy of the Upper Paleozoic in the southeastern Ordos based on the theory and method of Vail's classical sedimentary sequence theory.First of all,identifying the sequence boundary based on lithologic characteristics,cycle,and change of depositional characteristics.This paper pointed out that the upper and lower lithological assemblages of the secondary sequence boundary are greatly changed,and the lowstand sandbodies thickness on the secondary boundary is significant.The Benxi Formation to Shihezi Formation was divided into 3 two-order sequence and 11 three-order sequence.Secondly,system tracts in sequence were also divided according different stacking patterns and different migration style.The spatial superposition relationship of the sandbody in the Benxi Formation,Shanxi Formation and the Member 8 of Xiashihezi Formation in the sequence stratigraphic framework have been analyzed by means of the sequence of large-scale well logs and the detailed description of the core.The formation mechanism of the time-transgressive base level cycle is discussed considering that Ben-2 Zone was "barrier migration,blanket connectivity",Shan-2 Zone was a "lowstand controlling sand,surface-line connectivity" features,Shan-1 Zone was "lateral migration,contact connection",He-8 Zone has a "migration-swings stack,multi-directional connectivity" features on the gas-bearing strata of the Upper Paleozoic in the southeastern Ordos Basin.关键词
鄂尔多斯盆地/上古生界/层序地层/煤系含气地层/低位聚砂Key words
Ordos Basin/Upper Paleozoic/sequence stratigraphy/gas-bearing coal strata/sand accumulation in low-stand分类
天文与地球科学引用本文复制引用
于兴河,王香增,王念喜,单新,周进松,韩小琴,李亚龙,杜永慧,赵晨帆..鄂尔多斯盆地东南部上古生界层序地层格架及含气砂体沉积演化特征[J].古地理学报,2017,19(6):935-954,20.基金项目
国家自然科学基金项目(编号:41072084)资助.Financially supported by the National Natural Science Foundation of China (No.41072084) （编号:41072084）
