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采用单因素分析综合作图法,对塔里木盆地奥陶纪分五个作图单位进行定量岩相古地理研究及编图,即两河口—红花园期、大湾—牯牛潭期、庙坡期、宝塔期和临湘—五峰期。通过奥陶纪不同时期岩相古地理格局的变化,判断了不同时期海平面的变化,总体上看,两河口—红花园期到宝塔期是一个从东向西海进的过程,宝塔期到临湘—五峰期,古地理发生了重大变化,陆地面积增加,海域面积减少,表明塔里木盆地此时发生了海退。主要通过锶同位素地球化学等方法对塔北地区奥陶纪海平面升降进行了恢复,证实了两河口—红花园期到大湾—牯牛潭期海平面是个上升的过程。但在两河口—红花园期可以识别出两次海平面的相对下降,在大湾—牯牛潭期中期,也识别出了一次海平面下降。
Based on the single-factor analysis and integrated mapping method, the quantitative lithofacies palaeogeography and compilation of five Ordovician units in the Tarim Basin were studied, that is, the Lianghekou-Honghuayuan period, the Dawan-Huaniuitan period, the temple slope period , Pagoda period and Linxiang - Wufeng period. Through the change of lithofacies palaeogeographical pattern in different periods of Ordovician, the change of sea level at different periods is judged. Generally speaking, the process from the estuary to the pagoda of Lianghekou-Honghua Period is a process of proceeding from east to west, and pagoda period arrives In the Hunan-Wufeng period, significant changes have taken place in the paleogeography, with an increase in the land area and a decrease in the sea area, indicating that the reversion of the Tarim Basin occurred at this time. Mainly through the strontium isotope geochemistry and other methods to Ordovician seafloor elevation in northern Tarim recovered, confirmed that the two estuaries - Honghuayuan to Dayan - Huaniu Tan sea level is a rising process. However, two relative sea level declines were identified in the Lianghekou-Honghuayuan period, and a sea level decline was also identified in the middle of the Dayan-Huaniutian period.