在其大部分地质历史中,南美洲是由许多南半球陆地群组成的超大陆的一部分。南美洲在1.3亿年前开始与非洲分离,并在过去的5000万年中与南极洲分离。它是688万平方英里,是地球上第四大洲。南美洲主要有两个主要的地貌。安第斯山脉位于太平洋火环内,由南美板块整个西部边缘下的纳斯卡板块俯冲形成。与火环内的所有其他区域一样,南美洲容易发生火山活动和强烈地震。该大陆的东半部有几个克拉通,全年都超过10亿年。克拉通和安第斯山脉之间是沉积物覆盖的低地。该大陆几乎没有通过巴拿马地峡与北美相连,几乎完全被太平洋,大西洋和加勒比海洋所包围。几乎所有南美洲的大型河流系统,包括亚马逊河和奥里诺科河,都始于高地,向东流向大西洋或加勒比海。阿根廷的地质以西部安第斯山脉的变质和火成岩以及东部的大型沉积盆地为主。该国东北部的一个小部分延伸到拉普拉塔河畔克拉通。在南部,巴塔哥尼亚地区横跨太平洋和大西洋之间,包含世界上一些最大的非极地冰川。应该指出的是,阿根廷拥有一些世界上最富有的化石遗址,这些遗址都是巨大的恐龙和着名的古生物学家的家园。

澳大利亚昆士兰大学地质学Essay代写:南美地质

For much of its geologic history, South America was part of a supercontinent comprised of many southern hemispheric land masses. South America began to split apart from Africa 130 million years ago and separated from Antarctica within the past 50 million years. At 6.88 million square miles, it is the fourth largest continent on Earth. South America is dominated by two major landforms. The Andes Mountains, located within the Pacific Ring of Fire, are formed from the subduction of the Nazca plate underneath the entire western edge of the South American plate. Like all other areas within the Ring of Fire, South America is prone to volcanic activity and strong earthquakes. The eastern half of the continent is underlain by several cratons, all over one billion years in age. In between the cratons and Andes are sediment-covered lowlands. The continent is barely connected to North America through the Isthmus of Panama and is almost completely surrounded by the Pacific, Atlantic and Carribean Oceans. Almost all of South America’s great river systems, including the Amazon and Orinoco, begin in the highlands and drain east towards the Atlantic or Caribbean Oceans. Argentina’s geology is dominated by the metamorphic and igneous rocks of the Andes to the west and a large sedimentary basin to the east. A small, northeastern section of the country extends into the Río de la Plata craton. To the south, the Patagonia region stretches between the Pacific and Atlantic Oceans and contains some of the largest non-polar glaciers in the world. It should be noted that Argentina contains some of the world’s richest fossil sites that are home to both gigantic dinosaurs and famous paleontologists.

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