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火山对当地地质地貌的塑造具有很大的作用,通过研究阿拉斯加中南部的火山特征有助于进一步了解中南阿拉斯加的地质构造以及构造运动。在梳理火山成因以及中南阿拉斯加火山分布情况的前提下,对阿拉斯加中南部地区的火山特征进行了分析。指出:(1)从地质年龄的角度看,库克湾火山群的火山都很年轻,所有的火山都不到200万年,且最年轻的圣奥古斯汀火山才不到1.9万年,虽然年轻,但是除了海耶斯火山以外,库克湾地区的其他所有火山都很活跃。(2)兰格尔火山群与库克湾火山群差别很大,兰格尔火山群是阿拉斯加最老的活火山,它们可以追溯到500万~1000万年前的中新世,而且兰格尔火山群近期远不如库克湾火山群活跃。(3)科珀河(铜河)流域还分布着大量的泥火山,热水将细黏土沉积物从地下带到地表,形成大量的泥浆。这些泥浆的中心地区一般没有植物生长,泥火山当中最高的那座有300英尺高。除了这些泥火山之外,在格伦纳伦以西约10英里的地方,还有一座数十英尺高、面积达数百平方米的泥火山。
Volcanoes play a very important role in shaping the local geology and geomorphology. Studying the volcanic features in south-central Alaska helps to further understand the geological structure and tectonic movements of Alaska in central and southern China. On the premise of combing the genesis of volcanoes and the distribution of volcanoes in Alaska, the characteristics of volcanoes in central-southern Alaska are analyzed. (1) Volcanoes in the Cook Bay volcano are geologically age-old, with all volcanoes less than 2 million years old and the youngest St. Augustine volcano less than 19,000 years old, Although young, all the volcanoes in the Cook Bay area are active except for Mount Hayes. (2) The Ranger volcano and the Cook Bay volcano vary widely. The Ranger volcano is the oldest active volcano in Alaska, dating back to the Miocene between 5 and 10 million years ago, and Lange The recent volcano group is far less active than the Cook Bay volcano group. (3) There are also a large number of mud volcanoes distributed in the Copper River Basin. Hot water brings fine clay sediments from the ground to the surface to form a large amount of mud. The mud centers are generally not plant-grown in the center, and the tallest in the mud volcano is about 300 feet tall. In addition to these mud volcanoes, about 10 miles west of Glenrunren there is a mud volcano tens of feet high and hundreds of square meters high.