摘要:
西安已有3000余年的文明史,在其南部秦岭山峰中发育的多处大型基岩山崩体的形成历史与西安文明史一样久远,其中以西安市南30 km的翠华山大型山崩最为典型。该山崩体规模壮观,体量巨大,形态保存完整,景观奇特,被誉为中国“山崩奇观”,但其成因目前仍存争论。本文在野外调查与勘探基础上,对翠华山天池地段的山崩体形态特征、堆积体结构、成灾范围、形成年代、成因机理及其动力学过程进行研究。结果表明,翠华山山崩体体积约1.8×107 m3,山崩体的形成与距今2900年左右的古西周都城的消亡属同一时期的重大地震灾害事件;山崩过程包括孕育萌生、启动、加速、减速堆积等四个阶段,具有高速和长距离性;遗迹区内湖光、石海、断崖浑然一体,风景秀丽如画,具有奇、险、特、野之景观风格和极高的旅游观光价值。
关键词:
-
花岗岩
/
-
山崩
/
-
地震
/
-
地质遗迹
Abstract:
Xi’an is one of the oldest cities in China and has a civilization history of more than 3000 years. Recently, several large-scale rock avalanches have been found in peaks of the Qinling Mountains on the southern side of this city, and these rock avalanches might have a history as long as the city’s civilization. Among them, the Cuihua rock avalanche (CRA) located 30 kilometers to the south of Xi’an City is the most typical one, which, with characteristics of large scale, magnificent scene and good preservation, is called geological museum or miracle scenery of rock avalanche in China. Based on field investigation and geophysical prospecting, the authors studied such features of this rock avalanche as its geomorphology, volume, age, genetic mechanism and dynamics process. The results indicate that the volume of the rock avalanche is up to 1.8×107 m3 and its age is about 2900 years, suggesting that it resulted from the earthquake of 780 BC. The results of numerical simulation show that the whole failure process included four stages of starting up, accelerating, decelerating and accumulating; furthermore, the rock avalanche has some features of high speed and long distance. The study of the Cuihua rock avalanche has special importance for geological heritage protection, landslide research and tourism resources development.
下载: