重庆芙蓉洞崩塌作用及其环境效应
|
摘要
利用洞穴调查和各类次生化学沉积物同位素测年技术等方法,对芙蓉洞内崩塌物进行研究。结果表明芙蓉洞内崩塌物规模巨大,为多期次崩塌作用的产物,分别形成于大于35万年、35~20万年间、10~2.6万年间、2.5万年后及旅游开放后的1995、2000、2003、2008年,既有洞顶围岩的规模性崩塌,也有洞顶石钟乳的崩落和洞底石笋、石柱的倒塌,分别起因于地壳抬升背景下洞内水流下切使原先浮力消失引起洞顶围岩地应力失衡、洞顶石钟乳不断联合使重量超过联合体-洞顶围岩接触面的临界结合力和洞底石笋、石柱受崩落的钟乳石砸中或强地震引发。崩塌作用引起了洞腔的规模性扩大、钟乳石景观和旅游设施的破坏、被迫改变游览线路等环境效应。针对芙蓉洞崩塌特点,提出了洞穴旅游开发的一些建议。
Collapse of the Furong Cave in Chongqing City is studied by means of in-situ investigation and the U-series and 14C isotopic dating of speleothems.The results show that the enormous collapse piles were formed in different stages: 0.35Ma earlier,0.2~0.35Ma,0.026~0.1Ma,and 0.025Ma later BP as well as recent collapses following the exploitation of the cave for tourism(collapses occurred in 1995,2000,2003 and 2008).Three collapse phenomena are considered: roof stoping,falling stalactites,and tipping or falling of stalagmites and columns.Upward stoping results from the adjustment of stresses in the parent rock as buoyancy decreases when the groundwater table lowers due to tectonic uplift.This results in upward void migration and enlargement of the Cave passage.Stalactites fall as their weight increases beyond the critical force on the contact plane between the stalactites and parent rock.Stalagmites and/or columns tip and fall occur when the speleothems or parent rock are hit by falling stalactites or shook by earthquakes.The collapse functions are of the environmental effects as enlarge the space of the cave,damage of the stalagmites and tourism facilities,and make the tourism path has to be changed.Therefore,some proposals on cave tourism development are put forward according to the features of the collapses in the Furong Cave.
Collapse of the Furong Cave in Chongqing City is studied by means of in-situ investigation and the U-series and 14C isotopic dating of speleothems.The results show that the enormous collapse piles were formed in different stages: 0.35Ma earlier,0.2~0.35Ma,0.026~0.1Ma,and 0.025Ma later BP as well as recent collapses following the exploitation of the cave for tourism(collapses occurred in 1995,2000,2003 and 2008).Three collapse phenomena are considered: roof stoping,falling stalactites,and tipping or falling of stalagmites and columns.Upward stoping results from the adjustment of stresses in the parent rock as buoyancy decreases when the groundwater table lowers due to tectonic uplift.This results in upward void migration and enlargement of the Cave passage.Stalactites fall as their weight increases beyond the critical force on the contact plane between the stalactites and parent rock.Stalagmites and/or columns tip and fall occur when the speleothems or parent rock are hit by falling stalactites or shook by earthquakes.The collapse functions are of the environmental effects as enlarge the space of the cave,damage of the stalagmites and tourism facilities,and make the tourism path has to be changed.Therefore,some proposals on cave tourism development are put forward according to the features of the collapses in the Furong Cave.
引文
[1]朱学稳,张任,张远海,等.武隆县芙蓉洞旅游开发规划设计书[R].桂林中国地质科学院岩溶地质研究所,1993.
[2]Davies W E.Mechanics of cavern breakdown[J].NSS Bulletin,1951,13:36-43.
[3]朱学稳,黄保健,朱德浩,等.广西乐业大石围天坑群发现探测定义与研究[M].南宁:广西科学技术出版社,2003:139-153.
[4]朱学稳,朱德浩,黄保健,等.喀斯特天坑略论[J].中国岩溶,2003,22(1):51-65.
[5]张英骏.崩塌在喀斯特洞穴和地貌发育中的作用//中国地理学会地貌专业委员会.喀斯特地貌与洞穴.北京:科学出版社,1985:96-101.
[6]Klimchouk A.Cave un-roofing as a large-scale geomorphicprocess[J].Cave and karst Science,2005,32(2-3):93-98.
[7]朱学稳.芙蓉洞的次生化学沉积物[J].中国岩溶,1994,13(4):357-368.
[8]黄保健,韩道山,陈伟海.重庆武隆芙蓉洞稳定性调查评价报告[R].桂林中国地质科学院岩溶地质研究所,2003.
[9]White E L and White W B.Processes of cavern breakdown[J].NSS Bulletin,1969,31(4):83-96.
[10]刘斌.地震学原理与应用[M].合肥:中国科学技术大学出版社,2009:30-65.
[2]Davies W E.Mechanics of cavern breakdown[J].NSS Bulletin,1951,13:36-43.
[3]朱学稳,黄保健,朱德浩,等.广西乐业大石围天坑群发现探测定义与研究[M].南宁:广西科学技术出版社,2003:139-153.
[4]朱学稳,朱德浩,黄保健,等.喀斯特天坑略论[J].中国岩溶,2003,22(1):51-65.
[5]张英骏.崩塌在喀斯特洞穴和地貌发育中的作用//中国地理学会地貌专业委员会.喀斯特地貌与洞穴.北京:科学出版社,1985:96-101.
[6]Klimchouk A.Cave un-roofing as a large-scale geomorphicprocess[J].Cave and karst Science,2005,32(2-3):93-98.
[7]朱学稳.芙蓉洞的次生化学沉积物[J].中国岩溶,1994,13(4):357-368.
[8]黄保健,韩道山,陈伟海.重庆武隆芙蓉洞稳定性调查评价报告[R].桂林中国地质科学院岩溶地质研究所,2003.
[9]White E L and White W B.Processes of cavern breakdown[J].NSS Bulletin,1969,31(4):83-96.
[10]刘斌.地震学原理与应用[M].合肥:中国科学技术大学出版社,2009:30-65.
版权所有：© 2023 中国地质图书馆 中国地质调查局地学文献中心