摘要
根据坑探、物探、测温资料和含冰量、含盐度的分析,讨论了菲尔德斯半岛的冻土上限及其垂直梯度的变化,并论证了石环区碗状冻结面的存在,提出了本区地壳冷圈的五层结构,即活动层、冻结砂砾石层、受海水渗透作用过的冻结火山岩层、无海水渗透影响的冻结火山岩层和未冻结的古陆基底层;肯定了离岸海下冻土的存在;发现了含盐量高的冻土电阻率可低达80Ω.m,并对冰缘地貌发育有抑制作用。
The data of pitting, geoelectrical prospecting and temperature measuring, as well as analysis on ice (water) content and saltness indicated that the permafrost table of Astrofix Hilltop of Fildes Peninsula is 1. 5m depth, and the table can rise (or descend) 0.3-0.5m with altitude rising (or descending) 10m based on the hilltop. Frost table of stone circle has a bowl-shape of concave center. Cryosphere of continent-sea-ice-rock has a structure of five layers, namely, active layer, frost sand-gravel layer, frost volcanic rock permeated by sea water, frost volcanic rock unpermeated by sea water and unfrost ancient continental base. Thickness of permafrost is about 80 to 150m, and it showed an existence of offshore (subsea) permafrost.
In the place of high salt content, the electrical resistivity of the permafrost can lowly reach to 800m, meanwhile, the periglacio-geomorphic development are limited (e.g. widespread stone circle, sorted polygon and nets in the region).
出处
《南极研究》
CSCD
1990年第4期1-10,共10页
基金
国家南极考察委员会科学考察项目
关键词
冷圈
冻土
上限
乔治王岛
含盐度
cryosphere, permafrost table, bowl-shaped frost table, resistivity sound-ings, saltness.
