陕西南宫山南坡火山岩崩塌景观地貌形成演化

The Formation and Evolution of the Volcanics-collapsed Landform on the South Slope of Nangong Mountain in Shaanxi Province,China

南宫山国家地质公园景观地貌是研究崩塌地貌形态、成因和动力机制的典型野外实例。该地貌呈现出火山沉积砂砾岩的岩性特征及后期营力作用,属于典型基岩崩塌地貌。按照地貌各类要素的表现形态及分布特征,划分出崩塌母岩地貌、崩塌残存地貌、崩塌垮落地貌和崩塌堆积地貌四种类型,崩塌体典型运动方式为"解体→位移→崩落→堆积",其演化阶段可划分为解体、崩离、垮落、堆积及崩滑五个阶段。重力崩塌地貌易诱发地质灾害,应进行详细勘查,采取野外监测、设牌警示和工程治理等防治措施,保护人员及财产安全。

The landform in the Nangong Mountain National Geopark is a typical natural demonstration for geomorphology research on the volcanics-collapsed landscape. The lithology of sedimentary volcanic sandy conglomerate and the later erosional alternation features the landscape a typical of bedrock-collapsed topography. In accordance with the representative conformation and distribution characteristics of various elements of the landscape, four types of topographic features were classified which comprises the collapsed bedrock landforms, the collapsed relic landforms, the collapsed caving landforms and the collapsed stack landforms. The typical formation mode of the landforms was rebuilt as ＂disintegration→displacement→collapsing→accumulation＂. The evolutionary stage can be divided into five stages： disintegration, separating, collapsing, accumulating and landslip. Gravitational geomorphology are easy to induce geological disasters, and detailed investigations should be carried out. Field monitoring, warnings sign, and management measures should be taken to protect personnel and property safety in the Nangong Mountain National Geopark.