摘要
三清山花岗岩体形成于燕山晚期，岩体侵位定位后又经历了大约50Ma的侵蚀和剥蚀，将上覆5000m的地层搬到南北两侧的断陷盆地中，形成白垩纪红色砂岩和砂砾岩地层，花岗岩体便出露地表。又经过大约50～60Ma的构造演化和地貌演变形成了目前海拔1000～1800m的玉京峰期壮年地面和1200～1300m的怀玉山期壮年地面。至距今2．4Ma以前的上新世，在这两期古地面上曾先后发育了红色风化壳。红色风化壳的底部形成了众多的石蛋。进入更新世，随着地壳的强列抬升和气候变冷，冰冻风化、块体运动和流水侵蚀，古地面上的沟谷迅速向下侵蚀，古地面受到切割、破坏，风化壳也被侵蚀掉，形成深切峡谷、悬崖峭壁和柱、峰林立的景观，在柱、峰顶部残存着一些花岗岩石蛋。这种海拔超过1500m，相对高差超过1000m的高山地貌巍为壮观，石柱、尖峰显得十分秀丽，这就是三清山式地貌——高山尖峰地貌的特色，是提供旅人欣赏的主要花岗岩景观地貌，也是需要人们切实保护的重要地质遗迹。
The Sanqing Mountain granite formed in the late Yanshanian period, and after its emplacement, the granite experienced about about 50 Ma of erosion and denudation. As a result, the 5000 m thick overlying strata were transported to downfaulted basins at its northern and southern sides, thus forming Cretaceous red sandstone and sandy conglomerate, and then the granite was exposed subaerially. Afterwards, the granite again experienced about 50 ~ 60 Ma of tectonic and geomorphologic evolution, thus forming the present Yujingfeng-aged matureland 1600-1800 m above sea level and Huaiyushan-aged matureland 1200 -1300 m above sea level. In the Pliocene, 24 Ma BP, red weathering crust was developed on the paleolands of the two phases, with many ＂stone eggs＂ formed in the low-lying part of the red weathering crust. In the Pleistocene, valleys and gullies on the paleo-landform eroded downward rapidly with strong crustal uplifting and cooling, frost weathering, block movements and fluvial erosion. Thus the paleo-lands were cut and destructed and the weathering crust was also eroded away, forming a landscape of deep-incised valleys, steep cliffs and stone columns and peaks standing upright as trees, with some granite ＂eggs＂ still remaining on the top of these stone columns and peaks. Such a high-mountain landform with altitudes of more than 1500 m above sea level and a relative height difference of more than 1000 m is very magnificent and tall stone columns and pointed peaks look very beautiful. Those are just the features of the Sanqing Mountain-type granite landform -- the high mountain and pointed peak landform. They form the main granite landscape from which tourists may get a geoheritage for which effective protection measures great deal of enjoyment and are also an important should be taken.
出处
《地质论评》
CAS
CSCD
北大核心
2007年第B08期41-55,229-232,共19页
Geological Review
基金
三清山国家地质公园资助的<三清山花岗岩地质地貌发展演化研究>项目的成果之一
关键词
花岗岩景观地貌
三清山式地貌
高山尖峰地貌
granite landscape
Sanqing Mountain landform
high mountain and pointed peak landform
