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地层层序和地层分区研究是造山带地质研究的关键之一。过去通常以古生物及其古地理资料为主要依据划分对比地层 ,对哑地层则采用岩石地层方法。由于昌宁 -孟连带构造地层状况复杂 ,利用单一方法进行以上工作有困难 ,故采用了沉积环境分析、大地构造背景分析、阴极发光分析、古生物地理分析和物源分析相结合的方法对昌宁 -孟连带的地层成因及地层格架进行了探讨 ,按地层在沉积盆地中的原始位置 ,把昌宁 -孟连带地层分为东区、中区、西区。东区为大陆边缘地层区 ,包括南段群 (组 ) (D3- C1 )和拉巴群(C2 - P2 ) ;中区为洋盆地层带 ,包括准洋脊玄武岩及相应的硅质岩 (D3- P2 ) ,也可能包括部分腊垒群的硅质岩 ;西区地层区包括火山岩—碳酸盐台地地层序列 (C1 - P)、大陆边缘沉积的南皮河群 (D3- T1 )和腊垒群 (D1 - T2 )以及相应的陆壳至过渡壳的洋岛火山岩系
The study of stratigraphic sequence and stratigraphic division is one of the key issues in orogenic belt geology research. In the past, palaeontology and its paleogeographic data were usually used as the basis for the comparison of stratigraphic stratigraphy. For the dull strata, lithospheric stratigraphy was used. Due to the complex structure of Changning-Menglian tectonic strata, it is difficult to use a single method to carry out the above work. Therefore, the sedimentary environment analysis, tectonic setting analysis, cathodoluminescence analysis, palaeogeographical analysis and provenance analysis are used to analyze the Changning - Meng associated strata formation and stratigraphic framework were discussed, according to stratigraphic original position in the sedimentary basin, the Changning - Meng associated belt is divided into Eastern, Central, Western. The eastern margin is continental marginal zone, which includes the southern segment (Group D3-C1) and the Laba Group (C2 - P2). The middle zone is the ocean basin belt including Quasi-Yangji basalts and corresponding cherts (D3- P2), and may also include part of the Leidian siliceous rocks. The western strata include the volcanic-carbonate platform sequence (C1-P), the Nanpi River group (D3-T1) (D1 - T2) and the corresponding Oceanic volcanic rocks from the continental crust to the transitional crust