河北兴隆国家地质公园溶洞的成因及时代探讨  

The genesis and age of karst caves in Xinglong National Geopark,Hebei Province

作　　者：张皓月 姜群鸥[1] 张绪教[2] 王姗 ZHANG Haoyue;JIANG Qunou;ZHANG Xujiao;WANG Shan(School of Soil and Water Conservation,Beijing Forestry University,Beijing 100083,China;School of Earth Science and Resources,China University of Geosciences(Beijing),Beijing 100083,China)

机构地区：[1]北京林业大学水土保持学院,北京100083 [2]中国地质大学(北京)地球科学与资源学院,北京100083

出　　处：《地质力学学报》2025年第2期278-286,共9页Journal of Geomechanics

基　　金：国家自然科学基金项目(42301094);中央高校基本科研业务费专项资金项目(BLX202313)。

摘　　要：岩溶洞穴作为地球关键带的重要组成部分,兼具景观和科学研究价值。已有研究对与溶洞形成密切相关的构造报道较少,对溶洞形成时代的定量分析更是缺乏。文章基于河北省兴隆县陶家台洞穴形态特征、组成洞穴的地层产状和构造的详细调查,结合沉积物矿物X射线衍射和地球化学元素分析,对兴隆溶洞成因及时代开展了研究。组成溶洞的中元古代含燧石团块白云质灰岩中发育2条断层,溶洞自上而下顺断层倾向发育,属断裂构造形成的差异溶蚀型溶洞。洞穴中上部灌入的红土堆积与洞外风化壳残积红土的地球化学特征基本一致,且洞穴中发育有经地表水溶滤而富铁的红色钟乳石,表明洞穴内堆积的红土来源于洞外,溶洞形成时代应在红土形成之后。通过区域对比,地表残积红土为唐县期(3.1~3.7 Ma)夷平面的产物,说明溶洞形成时代应在上新世早期。文章提出了兴隆溶洞发育受控于断层的新认识,并较好地约束了其形成时代,可为其他区域岩溶地貌的成因及时代研究提供参考。[Objective]Karst caves,as an essential part of the Earth's Critical Zone,hold significant scientific and scenic value.However,previous studies have largely overlooked the tectonic factors influencing cave formation,and quantitative constraints on the age of cave formation remain scarce.This study aims to investigate the genesis and chronology of the Xinglong Karst Cave in the Taojiatai area of Hebei Province,elucidating the controlling factors and temporal constraints of cave development.[Methods]A comprehensive investigation of cave morphology,stratigraphic attitude,and tectonic characteristics was conducted,supplemented by mineralogical analysis using X-ray diffraction and geochemical element analysis.The study analyzed the relationship between cave formation and fault activity,while the geochemical composition of red clay deposits inside the cave was compared with external weathering crusts to constrain the formation age of the cave.[Results]The cave developed within Middle Proterozoic dolomitic limestone containing flint nodules,influenced by two major faults that facilitated differential dissolution along fault planes.The red clay deposits inside the cave share geochemical characteristics with external weathering crusts,indicating an exogenous origin.The enrichment of iron in red stalactites suggests leaching from surface water,further confirming the post-weathering deposition of the red clay.Regional comparisons reveal that the residual red clay outside the cave corresponds to the Tangxian planation period(3.1–3.7 Ma),indicating that the cave must have formed after this period.[Conclusion]This study provides new insights into the faultcontrolled genesis of the Xinglong Karst Cave and establishes a minimum formation age of 3.7 Ma,significantly younger than the Middle Proterozoic age of the host rock.The findings correct the previous misconception that the cave formed during the Proterozoic and highlight the crucial role of tectonic activity in cave development.[Significance]This research enhances our under

关 键 词：溶洞 构造 古土壤 地球化学 国家地质公园 兴隆县 

分 类 号：P642.25[天文地球—工程地质学] P596[天文地球—地质矿产勘探]