Читать книгу One Best Hike: Grand Canyon. Everything You Need to Know to Successfully Hike from the Rim to the River—and Back онлайн
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To answer these clusters of questions, and others, I describe the tectonic regimes to which the Grand Canyon area was subjected from 1.8 billion years ago until today, as the tectonic surroundings dictate many of the geologic processes that are recorded. These descriptions include information about the environments that led to the creation of the three main rock groups in the Grand Canyon: the Grand Canyon Metamorphic Suite, the Grand Canyon Supergroup, and Paleozoic sedimentary layers. (See page for descriptions of features that identify each rock layer.)
This brief description of the Grand Canyon’s geology is obviously incomplete. If learning a few tidbits piques your curiosity to learn more about the past and present processes that have created the landscape, check out the numerous books written on Grand Canyon geology (see page). Carving Grand Canyon by Wayne Ranney is especially recommended both to learn about what forces combined to create the Grand Canyon and to understand how geologists use field evidence to discern geologic processes. Ancient Landscapes of the Colorado Plateau’s scope (by Ron Blakey and Wayne Ranney) is broader than the Grand Canyon, but it does a superb job of describing historical environments in the Grand Canyon region, both through narrative and maps. Hiking the Grand Canyon’s Geology by Lon Abbott and Terri Cook provides a good introduction to the region’s geology, detailed information on the formation of the many rock layers, and a geologic guide to take with you as you hike along either of the trails described in this book. The U.S. Geological Survey provides an online geologic map and annotated photos from the South Kaibab and Bright Angel trails at: http://3dparks.wr.usgs.gov/grca/index.html.