淮南及淮北煤田第四纪“底砾层”成因模式探讨

Genetic Interpretation of the Quaternary Bottom Gravels in Huainan and Huaibei Coal Basins

安徽省淮南及淮北煤田第四纪“底砾层”的研究 ,对于煤矿提高上限开采具有重要意义。关于底砾层的成因问题 ,有多种观点。本文分析研究了两淮地区第四纪底砾层沉积面貌、描述了砾石外观形态 (如瓜子形、拖鞋状、葫芦状、马鞍状等 )及表构特征 ,包括泥包砾、镶嵌及缝隙结构等 ,提出两淮地区底砾层为冰碛物 (冰川沉积 )。地球化学测试及分析结果表明 ,两淮地区砾石的几种主要化学成分含量非常接近 ,从而说明两淮底砾层属同一物源。综合这两方面的论证 ,提出了底砾层的“停积—融坠型冰碛物沉积模式” ,并进行了冰碛物的物源方向问题的探讨。

The bottom gravel of Quaternary system in Huainan and Huaibei mine districts of Anhui Province has been studied for the upper limit of coal mining. There are many viewpoints about the genesis of the 'bottom gravel'. In this paper, the authors studied the depositional characteristics, described the morphology and surface textures of the Quaternary bottom gravels in these districts. It is proved that the bottom gravels in these two districts are glacial till (glacial deposit). Although these two mine districts are located about 200km away from each other, chemical similarity of limestone and dolostone gravels for these two districts indicates that these gravels share a common source. A 'stagnation and deposition falling stacking' model is proposed for genesis of these bottom gravels.