摘要
本文采用大量实际资料,阐述了常德市的地质构造特征,从第四系及新构造运动的特点论述了常德市不同地段工程地质稳定性的差异,对该市灼规划建设布局和防震、防洪等方面提出了一些新的看法和建议。
Changde city is situated in the Central Dongting fault depression, which is the contact zone of three different tectonic units. Apart from a little Cambrian strata in the northwestern corner and small amount of Cretaceous and Tertiary strata outcropped in the west and in the northeastern corner, the studied area is covered with Quaternary deposits, which cosists of 6 steps of in-laid terrace in the uprise and 4 steps of burried terrace in the subside. The area can be divided into 5 tectonic units i.e., Changde neo-fault subside(V_1), Hefu neo-fault uprise(V_2), Duogongzui neo-fault uprise(V_3)Deshan neo-fault uprise (V_4) and Meijiachong neo-fault uprise(V_5). A secondary tectonic unit (i.e. Dingcheng neo-fault depression in Jiajieci(V_6)can be distinguished from V_1. There are 4 groups of fault in the area, i.e., NNE, NE, NW and nearly EW trends, among which the NNE trend Taiyangshan fault zone is long-term active and is an earthquake-active zone. An earthquake of magnitude 6.5 in Changde in 1631 and another of magnitude 3.8 in Lixian in 1979 are closely connected with this fault zone. Based on the Quaternary geology and neo-tectonic history according to the stability of engineering geology, the Changde city can be classified into three types of area, that is, relative stable area, relatively substable area and relatively unstable area. The geologic disaster and environmntal problems of the city are also discussed. It is pointed out that the city should extend along area from the trifurcate road in the west of the city to Hefu and from Wuling town southwestward Guojiapu to Doumubu.
出处
《湖南地质》
1990年第1期19-27,共9页
Hunan Geology
关键词
城市
规划
地质构造
新构造运动
Geo-structure
Neo-tectonic movement
Fault
Earthquake
Neo-fault uprise
Nco-fault subside
