大青山煤田砂岩特征及其构造意义

对内蒙古大青山煤田砂岩的不同母岩的碎屑颗粒成分及其量比研究表明:晚石炭世-早二叠世中晚期盆地北侧陆源区母岩组合主要为下古生界寒武-奥陶系含燧石条带或结核的碳酸盐岩和碎屑岩以及上元古界震旦系石英岩,晚二叠世陆源区母岩组合主要为太古界古老变质岩和花岗岩及中酸性火山岩。晚石炭世-早二叠世早期陆源区构造作用表现为整体的平稳隆升,没有发生褶皱和冲断作用;早二叠世中晚期陆源区发生了较为强烈的隆升,还可能伴有冲断和褶皱作用;晚二叠世盆地北侧陆源区构造作用表现为显著的造山隆升作用和强烈的构造岩浆活动,并伴随着强烈的褶皱和冲断作用。综合研究表明,在晚石炭世初盆地北侧陆源区还曾保存有大面积的寒武-奥陶系乃至上元古界震旦系沉积盖层,说明晚石炭世以前,盆地北侧的陆源剥蚀区与整个华北地块是一个统一的、具有相同结构与演化历史和板块构造作用背景的整体,证明了“阴山古陆”并不是自元古代以来就长期隆升的构造单元。

The Characteristics and The Structural Significance of The Sandstone in Daqingshan Late Palaeozoic Coal-Gathering Basin

According to the contrast and research of the sandstones formed in the different stage, the fragment composition and content of its different parent rock, during the late Carboniferous to the middle-late stage of Early Permian, the parent rock assemblage at the north side land-source area of the Mount Daqingshan late Paleozoic coal-gathering basin mainly are the chert strip or nodule-bearing Carbonate and clastic rock from the lower Paleozoic Cambrian-Ordovician system and the quartzite from the upper Proterozoic Sinian; the terrigenous region tectogenesis just was table uplift wholly and no intensive folding and thrusting action. The terrigenous region thrusting and fold tectonism has begun by following the uplift of the stratum at the middle-late stage of Early Permian, and the strong fold deformation, overthrusting and obvious orogenic uplift processes also developed in the north side terrigenous region from the last Early Permian to late Permian. The research indicated that there also keep great area sediment caprock of the Cambrian-Ordovician system even the upper Proterzoic Sinian at the north side terrigenous region of late Carboniferous, it show before the late Carboniferous, the terrigenous denudation region in the north side of basin was the uniform whole with the North China massif with the same texture, evolvement history and plate tectonism background, as well as proved that the ‘Yinshan old-land’ not is the long term uplift tectonic unit since the Proterozoic.