摘要
根据大量的地质钻探资料结合多种物探手段,在查明金沙洲地质环境条件的基础上,深入分析金沙洲岩溶发育的控制因素、岩溶发育程度及岩溶发育的分布规律,并对碳酸盐岩的溶蚀机理进行了探讨。分析研究表明,金沙洲大面积碳酸盐岩岩溶发育受到矿物组分、结构构造、机械破坏、溶蚀面积和溶蚀率等多方面的综合影响;受断裂构造影响越强烈部位,岩溶越发育,沿断裂两侧各100m范围内,单孔岩溶率、单个溶洞高度及溶洞发育层数均明显强于外部范围;总体上,石磴子组及壶天群灰岩岩溶属中等-强发育等级,大塱山组泥质粉砂岩岩溶属弱发育等级;纵向上,灰岩岩溶发育强度随深度增加而呈递减态势,而可溶性泥质粉砂岩由于可溶岩组分分布不均匀,纵向岩溶发育强度的规律性不明显。进一步分析显示,在岩溶强发育地段有利于土洞的形成,并容易发生岩溶地面塌陷。
Using to the geological drilling data, on the basis of identifying the Jinshazhou geological environment conditions combination with a variety of geophysical exploration methods, factors controlling the karst development, the degree of karst development and karst distribution law near Jinshazhou in the southern Guangzhou-Huadu basin were thorough examined and the corrosion mechanism of carbonate rocks was also discussed. The results show that the karst development in the carbonates was effeeted by mineral components, structures, mechanical damage, corrosion area and dissolution rate. The impact of the fault structure, the single-hole karst rate, the height of the single cave and cave development layers in both sides of a fault structure within the range of 100 m were significantly stronger than the external areas. On the whole, the developmental level of karst in limestone of the Shidengzi group and the Hutian group is medium to strong, the developmental level of karst in argillaceous sandstone of the Dalangshan group is weak. Vertically,the karst development intensity in limestone shows a decreasing trend with increasing depth, while the regularity of soluble muddy siltstone is not obvious due to uneven distribution. Further analysis shows that the strong karst development is conducive to the formation of soil cave and prone to karst ground collapse.
出处
《水文地质工程地质》
CAS
CSCD
北大核心
2014年第1期138-143,共6页
Hydrogeology & Engineering Geology
基金
广州市白云区金沙洲岩溶地面塌陷
地面沉降地质灾害调查探测与监测(ZX2012411007008)
关键词
岩溶
发育特征
规律
控制因素
溶蚀
断裂构造
karst
developmental characteristics
law
controlling factors
dissolution
fault structure
