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在区域地质调查、实测地层剖面和区域对比基础上,对西藏西南部雅鲁藏布江缝合带西段的穷果群进行了研究,认为穷果群仅分布于萨嘎以西的仲巴微地体,萨嘎以东雅鲁藏布江缝合带中过去识别的穷果群实为构造混杂岩(三叠系—古近系)修康岩群的大型外来岩块;与下伏二叠系曲嘎群呈(侵蚀)假整合接触,上未见顶,与修康岩群之间可能不存在直接的整合/不整合接触关系;时代为三叠纪Induan期—Carnian期。依据岩相、层位差异,穷果群由下向上可划分为屯具场组、屯具日组和尼多曲组3个地层单元。屯具场组以石英砂岩为特征,向上夹含岩屑砂岩、粉砂岩和板岩或互层,厚30~550m,顶与屯具日组整合接触,时代暂置于早三叠世早期的Induan期,大多分布于霍尔巴—仲巴地区,其下部沉积环境为(可含障壁)滨岸,向上演变为为浅表海;屯具日组以晶粒灰岩为特征夹板岩/页岩、粉砂岩,或与之互层,产较为丰富的菊石、双壳类、牙形石等化石,厚200~800m,上未见顶或与尼多曲组整合接触,广泛分布于仲巴微地体,依据Claraia和Eumorphotis双壳动物群、Flemingites和Meekoceras菊石动物群、Neospathodus牙形石动物群,其时代可归属于早三叠世晚期的Olenekian期—中三叠世,沉积于较深陆表海环境;尼多曲组以黑色、深灰色碳质板岩为特征,厚300~500m,与下伏地层整合或假整合或断层接触,上未见顶,分布于仲巴地区,牙形石Metapolygnathus cf.polygnathiformis指示其时代为晚三叠世早期的Carnian期,沉积于深表海。
On the basis of regional geological survey, measured stratigraphic section and regional contrast, the study on the poor fruit groups in the western section of the Yarlung Tsangpo suture zone in southwestern Tibet shows that the poor fruit groups are only distributed in the Zhongba micro-body west of Saga, In the East Brahmaputra suture the past identification of the poor fruit group is actually the construction of melange (Triassic-Paleogene) Xunkang group of large intrusions; and the underlying Permian Quga group was (erosion) fake integration Contact, there is no top, there may not be any direct integration / unconformity relationship with Xukang Rock Group. The era is the Triassic Induan-Carnian Period. According to the lithofacies and horizon differences, the poor fruit group can be divided into three strata units: Tuenchangchang Formation, Tuenzuri Formation and Nidooqu Formation from bottom to top. The Tuenchangchang Formation is characterized by quartz sandstone that contains lithic sandstone, siltstone and slate or interbedded up to 30-550m thick. The top and Tunzai Formation are in integrated contact with each other, and the epoch was temporarily located in the early Triassic During the Induan period, most of them were distributed in the Halba-Zhongba area, and the sedimentary environment in the lower part of the Induan period was (barrier-free) and evolved into a superficial sea level. The Tunliu Formation was characterized by grain limestone. Rocks, siltstones, or with the inter-layer, producing more abundant ammonites, bivalves, conodonts and other fossils, thickness 200 ~ 800m, did not see the roof or integrated contact with the nido song group, widely distributed in the Zhong Baba, based on the Claraia and Eumorphotis bivalve, Flemingites and Meekoceras ammonites, and Neospathodus conodont fauna, dating back to the Early Triassic Olenekian-Middle Triassic, deposited in Which is characterized by black and dark gray carbonaceous slate with a thickness of 300-500m. It is in conformity with the underlying strata integration or fake integration or fault contact. There is no roof on the top, which is distributed in the Zhongba area. The teeth The Metapolygnathus cf. Polygnathiformis indicates that its age was the Carnian period of the early Late Triassic and deposited in the deep sea .