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通过对辽宁兴城地区中元古界长城系大红峪组底部的石英砂岩质砾岩的野外调研、砾石颗粒统计分析,在显微镜下分别对砾石的砂岩和填隙物的砂岩进行了岩相学研究、粒度统计分析等研究工作,结果显示砾石粒径大小为5mm～420mm,组成砾石的砂岩主要为细粒砂岩和粉砂岩,其中石英碎屑颗粒以跳跃方式搬运为主;填隙物砂岩的石英碎屑颗粒包括悬浮、跳跃、滚动形式搬运的3个次总体,其概率累积曲线研究显示代表性填隙物砂岩的各项参数为:平均粒径Mz=2.3、标准偏差σ1=0.83、偏度Sk1=-0.06、尖度KG=1.025、粒度参数Y=-5.585。因此认为:构成砾石的石英砂岩其沉积环境为滨浅海环境中的前滨与后滨亚相;填隙物的石英砂岩形成于滨岸带,属无障壁海岸相中的海岸沙丘亚相沉积;石英砂岩质砾岩的形成环境为冀鲁古陆边缘与胶辽边缘海交界处。此砾岩层的出现证实本区在大红峪早期发生过一次构造抬升。
Through the field investigation and gravel particle analysis of the quartz sandstone conglomerate at the bottom of the Dahongyu Formation in the Great Paleogene of the Great Paleozoic in Xingcheng, Liaoning, the gravelly sandstone and interstitial sandstone were analyzed under a microscope. Research, statistical analysis of granularity and other research work, the results show that the gravel size of 5mm ~ 420mm, composed of gravel sandstone mainly fine sandstone and siltstone, of which quartz chippings particles to skip the main transport; interstitial sandstone Quartz detritus includes three sub-populations of suspended, leaping and rolling modes. Probability accumulation curve shows that the parameters of representative interstitial sandstone are as follows: average particle size Mz = 2.3, standard deviation σ1 = 0.83, partial Degree Sk1 = -0.06, kurtosis KG = 1.025, particle size parameter Y = -5.585. Therefore, it is considered that the sedimentary environment of the quartz sandstone that constitutes the gravel is the foreshore and the backshore subfacies in the coastal shallow sea environment; the interstitial quartz sandstone is formed in the coastal zone and belongs to the coastal dune subfacies in the barrierless coastal facies; The formation environment of quartz sandstone conglomerate is the boundary between the edge of Jilu ancient land and Jiaoliao edge. The occurrence of this conglomerate confirms that there was a tectonic uplift in the early Dahongyu area.