The formation of Danxia landscapes is too slow to be observed in our life time and the paleoclimates in which Danxia landscapes developed are significantly different from the present. Thus, this study adopted experime...The formation of Danxia landscapes is too slow to be observed in our life time and the paleoclimates in which Danxia landscapes developed are significantly different from the present. Thus, this study adopted experimental approaches to examine the lithological and paleoclimatic control on the formation of various landscape morphologies in the Mt. Danxiashan, South China. A total of 122 rock samples were collected from a range of Danxia landscape morphologies such as white spots, small and large through caves, honeycomb caves, horizontal grooves, natural bridges, stone pillars, and squama stones. Analyses of the collected samples were conducted in different kinds of experiments, including uniaxial mechanical strength testing; rock resistance against sulfuric acid erosion, freezing, and thawing; X-ray fluorescence spectrometry（XRF） analysis; inductively coupled plasma mass spectrometry（ICP-MS） analysis; and identification analysis under a polarizing microscope. The results indicated that the formation of the various Danxia landscape morphologies could result from one or more of the following processes： differential erosion due to lithological difference, chemical dissolution and recrystallization, freezing and thawing actions, acid corrosion, weathering, lateral erosion of river flows, and tectonic uplifts. Water erosion in humid monsoon climate and the alternations of intensive freezing and thawing actions in the Quaternary glacial stages and the interglacial stages could have had great influences on the formation of Danxia landscape topographies.展开更多
Danxia Landform belongs to red terrestrial clastic rock landform, which is characterized by its red cliffed scarp. The development of Danxia Landform research in China experienced three historic stages, i.e. initial e...Danxia Landform belongs to red terrestrial clastic rock landform, which is characterized by its red cliffed scarp. The development of Danxia Landform research in China experienced three historic stages, i.e. initial establishment, taking shape and expanding since the concept 'Danxia Landform' raised by Prof. Chen Guoda in 1939. As a new branch of geomorphology, Danxia geomorphology research is now stepping its ripe stage. In the 1990s, the search enters into an unprecedented grand occasion at the prompting of tourism exploit.展开更多
高阻抗岩石地貌地区土壤电阻率较高,导致接地电阻较大,危及设备及人身安全。以岩石地貌地区较有代表性的220 k V源河变电站工程为例,详细阐述了接地降阻方案的选择过程,利用CDEGS软件建模仿真,对各接地降阻措施开展对比研究,选取最适合...高阻抗岩石地貌地区土壤电阻率较高,导致接地电阻较大,危及设备及人身安全。以岩石地貌地区较有代表性的220 k V源河变电站工程为例,详细阐述了接地降阻方案的选择过程,利用CDEGS软件建模仿真,对各接地降阻措施开展对比研究,选取最适合的接地降阻方案,同时为类似问题提供参考。展开更多
基金National Natural Science Foundation of China, No.41371204 No.41171163+6 种基金 No.41401216 National Science and Technology Basic Special Key Project, No.2013FY 11 1900 Foundation of State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, CAS, No.SKLLQG1206 No.SKLLQG1422 National Basic Science Personnel Training Project, No.J1103408 Foundation of Modern Analysis Center, Nanjing University, No.0422171010 Priority Academic Program Development of Jiangsu Higher Education Institutions, No.PAPD,Acknowledgements We appreciate the laboratory and field assistance of KONG Qingyou, LIU Di, YANG Li, WANG Xiaocui, FU Jingcheng, LIANG Guomin, MAO Xiaodong, FAN Dengfeng, LUO Jiehong, WU Huaan, TAN Ming, DAI Huibao, and XIE Zhangzhen.
文摘The formation of Danxia landscapes is too slow to be observed in our life time and the paleoclimates in which Danxia landscapes developed are significantly different from the present. Thus, this study adopted experimental approaches to examine the lithological and paleoclimatic control on the formation of various landscape morphologies in the Mt. Danxiashan, South China. A total of 122 rock samples were collected from a range of Danxia landscape morphologies such as white spots, small and large through caves, honeycomb caves, horizontal grooves, natural bridges, stone pillars, and squama stones. Analyses of the collected samples were conducted in different kinds of experiments, including uniaxial mechanical strength testing; rock resistance against sulfuric acid erosion, freezing, and thawing; X-ray fluorescence spectrometry（XRF） analysis; inductively coupled plasma mass spectrometry（ICP-MS） analysis; and identification analysis under a polarizing microscope. The results indicated that the formation of the various Danxia landscape morphologies could result from one or more of the following processes： differential erosion due to lithological difference, chemical dissolution and recrystallization, freezing and thawing actions, acid corrosion, weathering, lateral erosion of river flows, and tectonic uplifts. Water erosion in humid monsoon climate and the alternations of intensive freezing and thawing actions in the Quaternary glacial stages and the interglacial stages could have had great influences on the formation of Danxia landscape topographies.
文摘Danxia Landform belongs to red terrestrial clastic rock landform, which is characterized by its red cliffed scarp. The development of Danxia Landform research in China experienced three historic stages, i.e. initial establishment, taking shape and expanding since the concept 'Danxia Landform' raised by Prof. Chen Guoda in 1939. As a new branch of geomorphology, Danxia geomorphology research is now stepping its ripe stage. In the 1990s, the search enters into an unprecedented grand occasion at the prompting of tourism exploit.
