滇西保山金鸡地区三叠系上统大水塘组震积岩的发现及意义

以往认为保山地区三叠系上统大水塘组为浅海沉积，通过1∶5万金鸡村等幅区域地质调查，本文认为保山三叠系上统大水塘组的背景沉积主体为一套钙质浊积岩，主要由A、E段组成，中部夹薄层状硅质岩（饥饿沉积），并伴有滑塌岩块，属斜坡-盆地环境，是永德-黑山裂谷（海槽）的一部分。笔者在大水塘组中首次发现了震积岩，包括振动液化卷曲变形构造、微同沉积断层、液化泥晶脉、震积不整合、地裂缝、液化角砾、液化眼球及由地震使沉积物液化流动形成的滑（流）积岩、滑（流）褶皱等资料，这些现象组合规律性极差，仅有少量有垂向组合层序，显示出地方性属种的色彩。微同沉积断层、液化泥晶脉几乎充满沉积的全过程。岩石遭敲击时，都会散发出极浓的油气味，显示出良好的烃源岩特征。因此，研究大水塘组震积岩的分布和形成对于恢复三叠系上统大水塘组古地理环境及寻找烃源岩都具有非常重要的现实意义。

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

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∶ 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.