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每个地区的岩土和化石都能反应当地地质年代的变化,确定地层的年代等。文章在梳理岩石的类别以及黄土概念的基础上,对阿拉斯加中南部地区的岩土和化石情况进行了说明,指出:(1)中南阿拉斯加的岩石种类丰富,绝大部分基岩起源于各地体向北美克拉通贴附时隆起的海相沉积物;(2)马塔努斯卡河谷地区黄土层土壤十分肥沃,主要是由楚加奇山吹出的强风将附近冰川上的泥沙颗粒搬运到马塔努斯卡河谷的帕尔默周边地区后沉积下来形成的;(3)在中南阿拉斯加只发现了两处恐龙化石并且第三纪哺乳动物的化石和更新世的大型已灭绝的动物化石都很罕见。
Rock and soil and fossils in each region can reflect changes in the local geological age, to determine the age of strata and so on. Based on the classification of rocks and the concept of loess, this paper describes the geotechnical and fossil occurrence in south-central Alaska, and points out that: (1) There are abundant rocks in Central and Southern Alaska, with most of the bedrock originating from various places North American craton pasted uplift of marine sediments; (2) Loess Plateau in the Matanaska Valley is very fertile soil, mainly due to strong winds blowing from the Chugach Mountains to transport sediment particles from nearby glaciers to horses (3) Only two dinosaur fossils have been found in the Central South Alaska and both the Tertiary mammalian fossils and the Pleistocene large extinct animal fossils are very rare.