The Discovery and Significance on the Seismites of Dashuitang Formation in the Upper Triassic Series in Baoshan Jinji Area of Western Yunnan

Key words: 
• Upper Triassic series /
• Dashuitang Formation /
• seismites /
• hydrocarbon source rocks /
• Jinji /
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Abstract: Previously considered the Dashuitang Formation in the Upper Triassic series in Baoshan Area was shallow marine sedimentary environment. This paper argues that the background deposition of the Dashuitang Formation in the Upper Triassic series in Baoshan area subject to a calcareous turbidite by 1∶〖KG-*2〗50000 regional geological survey of Jinji Village site.It is mainly composed of the A, E segment that sandwiched thinbedded chert in central folder(Hunger deposition),accompanied by slump rock blocks,being classified for slopebasin environment, and is a part of the Yongde  Montenegro Rift Valley(Trough). For the first time, the author found the seismites in the Dashuitang Formation that including vibration liquefaction deformation structures, microfault with the micro deposition, liquefied micritic veins, seismic unconformity, fissure, liquefied breccia, liquefied eyeball, and sliding(Flowing) sedimentary rocks, slip (flow) folds, slump rock blocks of liquefied sediment flow of the earthquake. It is very poor that the regularity of combination of these phenomena. Only a small amount of them with vertical combination sequence that shows features of endemic species. MicroFault with the micro deposition and liquefied micritic veins are almost filled the whole process of the deposition.It can emit a very strong smell of oil when the rock was struck, that shows the good characteristics of hydrocarbon source rocks. Therefore, the study on the distribution and formation of seismites, Dashuitang Formation has very important practical significance that for the ancient paleogeographic environment of the Dashuitang Formation in the Upper Triassic series and the search for hydrocarbon source rocks.