A total of 80 weathering pits (gnammas), located on granite surfaces of Qing Mountain (青山), Hexigten (克什克腾) Global Geopark, Inner Mongolia, were identified and measured in terms of dimensional and orientat...A total of 80 weathering pits (gnammas), located on granite surfaces of Qing Mountain (青山), Hexigten (克什克腾) Global Geopark, Inner Mongolia, were identified and measured in terms of dimensional and orientational features. This article attempts to extract characteristics of the weathering pits by descriptive statistics and orientation rose diagrams, investigate the multi-phase evolution by the modified gnamma morphological analysis (GMA) method, and shed new light on the possible genesis and the influencing factors. Following the modified GMA method, weathering pits in Qing Mountain have been divided into six groups and compared with analogous sites to deduce their approximate age, which might be no older than 30 ka B.P., and explore the possibility that the multi-phase evolution of weathering pits may arise from responses to climate change. In consequence, we suggest that the combination of weathering, especially salt weathering, and wind erosion, both of which are closely related to climatic variation, take the main responsibility for the formation and development of weathering pits in Qing Mountain.展开更多
基金supported by China Geological Survey(No.11212011120118)the Fundamental Research Projects of China University of Geosciences,Beijing,China(No.2011YYL016)
文摘A total of 80 weathering pits (gnammas), located on granite surfaces of Qing Mountain (青山), Hexigten (克什克腾) Global Geopark, Inner Mongolia, were identified and measured in terms of dimensional and orientational features. This article attempts to extract characteristics of the weathering pits by descriptive statistics and orientation rose diagrams, investigate the multi-phase evolution by the modified gnamma morphological analysis (GMA) method, and shed new light on the possible genesis and the influencing factors. Following the modified GMA method, weathering pits in Qing Mountain have been divided into six groups and compared with analogous sites to deduce their approximate age, which might be no older than 30 ka B.P., and explore the possibility that the multi-phase evolution of weathering pits may arise from responses to climate change. In consequence, we suggest that the combination of weathering, especially salt weathering, and wind erosion, both of which are closely related to climatic variation, take the main responsibility for the formation and development of weathering pits in Qing Mountain.