| Abstract: | Much of the ground surface around Mount Rainier volcano is directly underlain by loose geologic deposits that veneer the hard rock formations. Examples of these deposits are sand and gravel bars along the rivers, ridges of loose rock debris beside the glaciers, and sloping aprons of rock fragments beneath almost every cliff. Even though they are generally thin and inconspicuous when compared with the rock formations, these surficial deposits are clues to geologic events that have profoundly influenced the shape of the park‘s landscape. Thus, from the character and extent of glacial deposits one can judge the age and size of former glaciers that carved the cirques and deep canyons of the park; from the mudflows which streamed down nearly every valley one can infer the age and size of huge landslides of the past that helped determine Mount Rainier‘s present shape; and from the pumice deposits some of the volcano‘s recent eruptive activity can be reconstructed.
The map (plate 1, in pocket) that accompanies this description of the surficial deposits of Mount Rainier National Park shows the location of the various geologic formations, and the explanation shows the formations arranged in order of their relative age, with the oldest at the bottom. The text describes the surficial deposits in sequence from older to younger. A discussion of the pumice deposits of the park, which were not mapped, is followed by a description of the formations shown on the geologic map.
Inspection of the geologic map may lead the viewer to question why the surficial deposits are shown in more detail in a zone several miles wide around the base of the volcano than elsewhere. This is partly because the zone is largely near or above timberline, relatively accessible, and the surficial deposits there can be readily recognized, differentiated, and mapped. In contrast, access is more difficult in the heavily timbered parts of the park, and surficial deposits there are generally blanketed by a dense virgin forest and are rarely exposed. Geologic investigations in such areas of the park were of a reconnaissance nature. |
| Genre: | USGS Numbered Series |
| ProdID: | 34086 |
| Citation Author: | Crandell, Dwight Raymond |
| Citation Contributing Office: | U.S. Geological Survey |
| Citation Datum: | |
| Citation Day: | |
| Citation Edition: | - |
| Citation Editor: | |
| Citation End Page: | |
| Citation Issue: | |
| Citation Keywords: | |
| Citation Language: | ENGLISH |
| Citation Larger Work Title: | |
| Citation LatN: | 0470000 |
| Citation LatS: | 0464000 |
| Citation LonE: | -1212500 |
| Citation LonW: | -1220000 |
| Citation Month: | |
| Citation No Pagination: | |
| Citation Number Of Pages: | |
| Citation Online Only Flag: | |
| Citation Phsyical Description: | 41 p. |
| Citation Projection: | |
| Citation Public Comments: | |
| Citation Publisher: | U.S. Geological Survey |
| Citation Series: | Bulletin |
| Citation Series Code: | B |
| Citation Series Number: | 1288 |
| Citation Search Results Text: | Surficial Geology of Mount Rainier National Park, Washington; 1969; B; 1288; Crandell, Dwight Raymond |
| Citation Start Page: | |
| Citation Volume: | |
| Citation Year: | 1969 |
| Type: | citation/reference |
| Text: | Surficial Geology of Mount Rainier National Park, Washington; 1969; B; 1288; Crandell, Dwight Raymond |
| URL (THUMBNAIL): | http://pubs.usgs.gov/bul/1288/report-thumb.jpg |
| URL (INDEX PAGE): | http://www.nps.gov/history/history/online_books/geology/publications/bul/1288/index.htm |
| URL (DOCUMENT): | http://pubs.usgs.gov/bul/1288/report.pdf |
| URL (INDEX PAGE): | http://ngmdb.usgs.gov/Prodesc/proddesc_21385.htm |
| Date Other: | Sat, 1 Jan 1994 00:00 -0600 |
| Publisher: | U.S. Geological Survey |
