摘要
阿尔泰山第四纪期间曾广泛发生冰川作用,其中东山区古冰川遗迹保存较好。本文通过对西岔河矿区砂金矿的研究,认为古冰川作用与砂金矿有较为密切的关系。古冰川作用不仅产生了各种地貌形态,而且为后期砂金矿的形成创造了条件。
Altai Mts, known as Gold Mountain, lies in northern margin of Xinjiang Region. Influenced by cold climate in Quaternary, glaciers had been widely developed at this area. In the zonations of middle and high mountains, paleoglacial vestiges well remained. Studies of paleoglacial vestiges show that there were at least three glacial stages during pleistocene. The scale of glaciation culminated in the middle pleistocene.
The intense paleoglaciation had not only modeled various landforms, but also created favourable conditions of gold placer formation. First, the paleoglaciation broke down geological mass containing golds and produced tremendous rock fragments. Secondly, the paleoglaciation destroyed the stability of the residuum, accelerating weathering speed to release the gold from parent rocks. Thirdly, the glacial abrasion could grind parent rocks. These processes made gold grains isolate. At the same time, a large amounts of fine gold
grains were available as crystal nucleus for chemical deposition of gold.
In the paleoglaciation area of Altai Mts there are many glod placers. 'East Mountain Region' is a concentrated region of moraine gold placer. According to time of the formation, three types of the gold placer can be divided in this region, they are: the pre-glacial period, the glacial period and the past-glacial period.
出处
《冰川冻土》
CSCD
北大核心
1992年第1期63-72,共10页
Journal of Glaciology and Geocryology
基金
阿尔泰山砂金沉积规律研究成果之一
关键词
冰川作用
第四纪
砂金矿
阿尔泰山
Quaternary, paleoglaciation, gold placer, glacial abrasion
