摘要: |
通过对云南乌蒙山区彝良地区中下三叠统6条野外地质剖面测量及500余片岩石薄片镜下观察,结合区域构造特征,将该地区中下三叠统划分为6个三级层序。岩石类型主要为泥铁质粉砂岩、细粒长石岩屑砂岩、含钙质泥质粉砂岩、细粒岩屑砂岩、钙质胶结细粒岩屑砂岩、含生物屑泥晶灰岩、泥灰岩、泥灰岩-含海绿石铁质生物屑亮晶砂屑灰岩、微晶灰岩-泥晶灰岩-含海绿石泥晶砂屑灰岩、亮晶鲕粒灰岩、含粉砂质泥质微晶灰岩、微晶灰岩等。结合沉积物的结构特征、组分及其组合特征,认为彝良地区中下三叠统的沉积相主要为海岸和碳酸盐岩开阔台地相。 |
关键词: 嘉陵江组 中下三叠统 沉积相 层序地层学 |
DOI: |
附件 |
投稿时间:2019-05-30修订日期:2019-07-22 |
基金项目:本文受地质调查项目“乌蒙山区地质矿产综合调查”DD20160019(121201010000150002)资助 |
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Sequence stratigraphy and sedimentary facies of the Middle to Lower Triassic strata in the Wumeng mountain area, Yunnan: A case study of the Yiliang region |
SHEN Tao1, YANG Bin2, LIN Jiqing1, JI Panlong3, LIU Qisheng1, TU Zonglin1 |
(1. No. 403 Geological Prospecting Party, Sichuan Bureau of Geology and Mineral Resources, Emeishan 614200, Sichuan, China; 2. Chengdu Center, China Geological Survey, Chengdu 610081, Sichuan, China; 3. College of Earth Sciences, Chengdu University of Technology, Chengdu 610059, Sichuan, China) |
Abstract: |
The Middle to Lower Triassic strata in the Yiliang region, Wumeng mountain area, Yunnan are divided into six third-order sequences in the light of detailed examination of six geological sections, and grain size and lithological analysis of more than 500 pieces of rock samples collected from the study area. The rock types include muddy-ferruginous siltstone, fine-grained feldspathic lithic sandtone, calcareous-muddy siltstone, fine-grained lithic sandstone, fine-grained calcareous lithic sandstone, bioclastic micritic limestone, marl, marl-glauconitic ferruginous bioclastic spararenite, micritic limestone-glauconitic micritic arenite, sparry oolitic limestone, siltymuddy micritic limestone, micritic limestone, etc. According to the texture, composition and mineral assemblage, the Middle to Lower Triassic strata in the Yiliang region should be assigned to the coastal and open carbonate platform facies deposits. |
Key words: Jialingjiang Formation Middle to Lower Triassic strata sedimentary facies sequence stratigraphy |