摘要
前人研究多认为四川盆地北缘及秦岭地区震旦纪—寒武纪为深海斜坡或台地边缘斜坡,而在该区古地理编图过程中发现,本区碳质泥岩、石煤为地表或近岸浅水滞留环境如沼泽、澙湖的沉积产物,非深水或深海环境的沉积产物。为此,通过对川北野外剖面精细观察和实测、钻井资料深刻分析和对比,并结合地震剖面的解释和控制,对研究区进行了综合剖面相分析、剖面对比相分析及平面剖面相分析;同时参考前人有关该区的构造层序古地理、定量古地理和生产古地理编图资料,通过优化编制震旦纪—寒武纪以世或段(期)为单元的古地理图,认为四川盆地北缘秦岭地区震旦纪—寒武纪的古地理格局主要由潮坪、澙湖、泥碳沼泽、滨岸、局限台地等相带或古地理单元所构成,而非深海盆地、斜坡或台地边缘斜坡。
Most previous studies suggest that the lithofacies palaeogeography of northern Sichuan Basin and Qinling ar- ea is the deep-sea slopes or slopes of platform margin during the Sinian-Cambrian. However, in the process of paleo- geographic mapping in this area, it was discovered that the Carbonaceous mudstone and the stone coal are deposited in the surface water or near shore shallow water, such as swamps and lagoons, rather than in the deep water or the deep sea. Therefore, based on the detailed observation , the measurement of outcrop profiles and the profound analysis of the well datas, and combined with the interpretation ofseismic profiles in the northern Sichuan Basin, the comprehen- sive analysisof the single section facies, cross section facies and facies mapping were made; meanwhile, by referring to the tectonic palaeogeography, quantitative palaeogeography and production palaeogeography in the area, the paleo- geographic maps were drew optimally from the Sinian to Cambrian.It was concluded that the palaeogeographic frame- work in the area of northern Sichuan Basin to Qinling area mainly consists of tidal fiats, lagoons, peat swamps, shores and restricted platform facies, rather than the facies of the deep-sea basin, slopes or margin slopes of platform during the Sinian-Dambrian.
出处
《沉积学报》
CAS
CSCD
北大核心
2014年第1期1-7,共7页
Acta Sedimentologica Sinica
基金
"十二五"国家科技重大专项(编号:2011ZX05005-002)
国家重点基础研究发展计划(编号:973计划)项目(编号:2012CB214802)联合资助
关键词
四川盆地北缘
秦岭
震旦-寒武纪
古地理
潮坪白云岩
沼泽澙湖
the northern Sichuan Basin
Qinling
Sinian-Cambrian
palaeogeography
dolomite of tidal flat
swampand lagoon
