<span>it is the study of human activities on the surface of the globe
(regions inhabited <span>by men)</span></span>
The US received more than 20 million immigrants.
The major geological process of this Era was denudation. The gigantic mountains that were formed by the Precambrian orogeny were subjected to intense and prolonged denudation. At the end, the once gigantic mountain ranges were reduced to a “peneplained” surface.
