Remote sensing in exploration geology. Field Trip Guidebook / Дистанционное зондирование в разведочной геологии

The earliest people in the Front Range area left scant record. During the Pleistocene, the first migrations of Oriental people crossed the Bering land bridge and some eventually moved into Colorado. Cliffdwelling Pueblo cultures developed in southwestern Colorado about 2000 years ago, with more nomadic tribes like the Ute and Apache arriving in Colorado about 700 years ago (Brown, 1985).
By the middle of the eighteenth century, the Pawnee had firm control of the South Platte River, with the Comanches to the south. Decimated by smallpox, the Pawnees moved northeast, and the dominant plains tribes became the Cheyenne and Arapahoe, who hunted from the Arkansas River to the North Platte River. Several tribes of Utes continued to inhabit the mountains.
One of the earliest known Europeans to arrive in the Front Range area was Juan Bautista de Anza. In 1779 he led troops north from Santa Fe and chased Chief Cuerno Verde and a band of his Comanches through Poncha Pass and onto the plains below Pikes Peak (Sprague, 1976).
President Thomas Jefferson doubled the size of the u.s. in 1803 by acquiring from Napoleon the Louisiana Purchase, comprising everything Napoleon owned west of the Mississippi River (a bargain at four cents an acre). The eastern part of what became Colorado was included in the Purchase, with the western half owned by Charles IV of Spain (later acquired from Mexico). The boundary was in dispute, being either the Arkansas River or the Red River <...>