摘要
在层序格架内研究川东北元坝地区三叠系飞仙关组碳酸盐岩台地演化及其影响因素。元坝地区三叠系飞仙关组划分为2个三级层序、4个体系域。元坝地区飞仙关组碳酸盐岩台地在不同时期、不同区域受到构造抬升和高位溢流的影响。在层序SQ1海侵期,元坝北部受到构造抬升的影响,外缓坡外侧沉积厚度反而大于外缓坡内侧厚度。从层序SQ1海侵期持续到高位初期的构造抬升减小了台地中缓坡与外缓坡的差异,促使台地规模迅速向北扩大。在层序SQ1高位期,元坝东部高位溢流现象显著。高位期台地可容纳空间减小,限制了台地的垂向加积潜力,沉积物向外缓坡方向侧向前积,出现高位溢流。鲕滩主要发育在高位溢流不同阶段所形成的中缓坡和缓坡斜坡内。
In this paper the evolution and it’s influence factor for the carbonate platform of Triassic Feixianguan Formation in Yuanba Area,Northeast Sichuan Basin was studied in the sequence framework.The Feixianguan Formation in Yuanba Area was divided into 2 third-order sequences,and 4 systems tracts.The Feixianguan Formation carbonate platform in Yuanba Area were affected by tectonic uplift and highstand shedding in different periods and different regions.In sequence SQ1 marine transgressive period,the north of the Yuanba area was affected by tectonic uplift,the lateral sediment thickness of the outer gentle slope is greater than the medial sediment's thickness of the outer gentle slope.The tectonic uplift from sequence SQ1 marine transgressive period to tectonic uplift in initial stage of high elevation period decreases the difference between the gentle slope on platform and the outer gentle slope,resulting in rapid expansion of the platform to the north.In sequence SQ1 high elevation period,the highstand shedding phenomena was remarkable in East of Yuanba Area.For high elevation period the accommodation for platform decreases,limiting vertical thicking potential for the platform,the sediment progrades laterally towards outer gentle slope,and the highstand shedding appears.The oolite beach mainly develops inside the slightly gentle slope and gentle slope which were formed in different stages of highstand shedding.
出处
《石油地球物理勘探》
EI
CSCD
北大核心
2010年第3期410-413,共4页
Oil Geophysical Prospecting
基金
国家973项目(2005CB422105)
"构造与油气资源"教育部重点实验室开放课题(TPR-2009-32)资助
关键词
缓坡
高位溢流
层序
元坝地区
四川盆地
gentle slope,highstand shedding,sequence,Yuanba Area,Sichuan Basin
