document.write=function() {}; document.writeln=function() {};
Home Archived Aug 4, 2016

USGS Geology in the Parks

Geologic story of the North Cascades button North Cascades National Park:
Early Encounters with the Rocks

Petrographs on the shores of Lake Chelan, painted by early North Cascade residents

The first explorers in the North Cascades who had an interest in rocks may well have been the native peoples, quarrying chert and volcanic glass for tools and weapons. According to archaeologists, hunters quarried chert for weapons as early as 8,000 years ago in the Skagit River valley near what is now Ross Lake. Based on radiocarbon ages of old campfires at quarry sites, archaeologists estimate that the early rock-workers were most active in the mountains between 3,500 and 4,000 years ago.

Native peoples established trails over some passes in the North Cascades. The first Europeans, seeking furs, gold and trade routes, followed these trails. By the 1890s, mining claims were established in many areas, including in the vicinity of Harts Pass in the Pasayten Wilderness, the upper North Fork of the Nooksack in the Mt. Baker Wilderness, and the Cascade Pass area of North Cascades National Park. The first professional geographer to see a significant part of the back country was George Gibbs, who in 1849 explored the Skagit, Chilliwack, and Pasayten drainages. His travel was no doubt difficult, but his rather dry account does no justice to the magnificence of the country.

In the early 1900s, as part of a resurvey of the border along the 49th parallel, Canada and the United States sent geologists to study the area along the border. George Otis Smith and Frank Calkins of the U.S. Geological Survey worked on the U.S. side. Although Smith and Calkins made significant contributions, their report pales beside that of their Canadian counterpart, a young professor from Boston named Reginald Daly.

Daly's cross section
Part of a cross section along Canadian border from Daly’s 1912 report. It shows young volcanic rocks (volcanic rocks of Mount Rahm) resting on rocks of the Hozomeen terrane and intruded by a younger pluton of the Chilliwack batholith.

Lumberjacks had cleared trees from a 100-foot-wide swath along the border, allowing Daly, usually mounted on a horse and following the tree fellers' trails, to reach terrain never seen before by geologists. His extensive report, published in 1912, was, for more than 40 years, the major source of geologic lore for the North Cascades. However, vast parts of the North Cascades remained unknown geographically and geologically until more recent times.

Material in this site has been adapted from a book, Geology of the North Cascades: A Mountain Mosaic by R. Tabor and R. Haugerud, of the USGS, with drawings by Anne Crowder. It is published by The Mountaineers, Seattle.

Accessibility FOIA Privacy Policies and Notices

Take Pride in America logo logo U.S. Department of the Interior | U.S. Geological Survey
Page Contact Information: Webmaster
Page Last Modified: 02-Oct-2014@13:05