摘要
韶关新区碳酸盐岩分布面积广,溶洞发育,对工程建设影响大,制约了城市的建设与发展,查明韶关新区覆盖型岩溶发育情况及分布规律,对韶关新区发展规划、重大项目选址等具有重要意义。通过资料收集整理、钻探等方法,对韶关新区的岩溶类型、岩溶发育与地层岩性组合、地质构造、地下水关系进行了研究,总结了岩溶发育规律及主要控制因素。区域岩溶发育平面空间上受区域性北东向构造和可溶岩展布控制,覆盖型岩溶整体呈北东向带状分布,平面岩溶发育程度可分为极强发育、强发育、中等发育和弱发育四个级别区。垂向上岩溶发育随深度的增加整体呈减弱趋势,由浅到深依次分为极强发育带、强发育带、中等发育带和弱发育带。岩溶发育主要受地层岩性、地下水活动和地质构造等因素控制,芙蓉盆地边缘梓门桥组不纯碳酸盐岩与壶天组纯碳酸盐岩接触带、江湾张屋岭和甘棠工业园区地下水强径流带、断层破碎带及芙蓉山向斜核部等区域,有利于地下水的流动,加剧了可溶岩的溶解作用,因而也加速了这些区域溶洞的形成和发育。
The carbonate rock in the Shaoguan New District is widely distributed,and the covered karst caves are well-developed,exerting a significant influence on engineering construction and restricting the city’s construction and development.Through research on the karst types,karst development and its stratum lithology combinations,geological structures,and groundwater relationships in the Shaoguan New District,we summarized the karst development patterns and main controlling factors.The findings provide valuable guidance for the planning and urban construction of the Shaoguan New District.The covered karst area in the Shaoguan New District is mainly distributed in the valley plain and is roughly divided into three regions by the surrounding hills:the Xilian–Gantang karst valley,the karst syncline basin in Furong New City,and the terrace of the Beijiang River in the Jiangwan Area,encompassing a total area of 35 km².Horizontally,controlled by regional northeast-oriented structures and the distribution of soluble rocks,etc.,karst in the study area is generally distributed in a northeast-oriented band.According to the lithology combination,groundwater recharge and runoff conditions,geological structures,topography,and detection rates of karst caves in boreholes,the degree of development of covered karst can be classified into four levels:extremely strong development,strong development,moderate development,and weak development.The area characterized by extremely strong karst development is approximately distributed in a northeast-oriented band,with a detection rate of karst caves generally exceeding 60%.This area can be broadly categorized into three types.The first type is mainly affected by lithology combinations,exemplified by the region surrounding Furongwan–Shaoguan Avenue–Hengda City,which is located near the lithological contact zone between the Hutian Formation and the Zimenqiao Formation.The second type is mainly affected by geological structures and lithology,as seen in Baoneng Mansion and the northeastern side of Xiahu Village located in the core of the Furong Mountain Syncline.The stratum lithology consists of the limestone and dolomitic limestone in the Hutian Formation,which is brittle and leads to highly developed rock joints and fractures,thereby providing favorable spaces and channels for groundwater activities.The third type is mainly affected by groundwater recharge and runoff conditions.For example,the Zhangwuling in Jiangwan and the Gantang Industrial Park are located in areas of strong runoff where groundwater discharges into the river.The intense groundwater activities in these locations provide favorable hydrodynamic conditions for karst development.The area characterized by strong karst development has a wide area and is mainly distributed in Xilian Town–Muxi Industrial Park,Gantang Industrial Park,the Furong Syncline Basin,and the south of Baimang Reservoir.The detection rates of karst caves range from 30%to 60%,and these caves are mostly distributed in the areas of groundwater runoff.The area characterized by moderate karst development is mainly distributed in Muyang Avenue–Muxi Industrial Park,Chishui New Village,the New Party School,and Cuntou,etc.The detection rates of karst caves range from 10%to 30%,and the soluble rocks are mainly from the Shidengzi Formation.The area characterized by weak karst development is mainly distributed in the peripheral regions of moderate development,and the detection rates of karst caves are generally less than 10%.Vertically,there are significant differences in karst development within the study area,which exhibit a diminishing trend as the depth increases.From shallow to deep,the area can be divided into four zones:extremely strong development,strong development,moderate development,and weak development.The zone of extremely strong karst development extends from the bedrock surface to a depth of 40 m,with detection rates of karst caves in the 20 m to 40 m depth range reaching 45%.These karst caves are mostly filled with silty clay.The zone of strong karst development is distributed at depths of 40 m to 60 m below the surface,where the detection rate of karst caves is 35%.In this zone,the karst caves are mainly fully filled or semi-filled.The zone of moderate karst development is distributed at depths of 60 m to 80 m below the surface,with a detection rate of karst caves being 20%.These caves are mainly semi-filled or unfilled.The zone of weak karst development is distributed at depths greater than 80 m,where the detection rate of karst caves is less than 10%.In this zone,the karst caves are mostly empty,with a few being semi-filled.The degree of karst development results from the interaction of various factors.Among the three areas of covered karst,the karst basin of Furong New Town is located in the core of the Furong Mountain Syncline structure,where the geological strata mainly consist of pure carbonate rocks,including the limestone and dolomitic limestone of the Hutian Formation,which are inherently brittle.The influence of the syncline structure has led to significant fracturing of the rock in the core area,providing optimal conditions for groundwater flow and dissolution.Additionally,the basin is located within a region of active groundwater flow,characterized by strong hydraulic action that can facilitate the formation and development of karst.Therefore,the overall degree of karst development in the karst basin of Furong New Town is stronger than that observed in the Xilian–Gantang karst valley and the terrace of the Jiangwan karst river.
作者
陈珲
龚锦钊
管振德
张文平
张云飞
谢昌阳
徐耀
CHEN Hui;GONG Jinzhao;GUAN Zhende;ZHANG Wenping;ZHANG Yunfei;XIE Changyang;XU Yao(Shaoguan Geological Survey Center,Guangdong Geological Bureau,Shaoguan,Guangdong 512000,China;Institute of Karst Geology,CAGS/Key Laboratory of Karst Dynamics,MNR&GZAR/International Research Centre on Karst under the Auspices of UNESCO,Guilin,Guangxi 541004,China)
出处
《中国岩溶》
北大核心
2025年第3期598-608,共11页
Carsologica Sinica
基金
中国地质科学院岩溶地质研究所基本科研业务费项目(202317)。
关键词
韶关新区
岩溶
发育特征
分布规律
Shaoguan New District
karst
developmental characteristics
distribution law
