The Church Mountain Sturzstrom (Mega-Landslide), Glacier, Washington
- Western Washington Univ., Bellingham, WA (United States). Dept. of Geology
Detailed investigation of an ancient sturzstrom or mega-landslide near Glacier, Washington has revealed it areal extent, approximate volume, age, geomorphology, source area, and possible causes. Stratigraphic and lithologic investigations indicate Church Mountain as the source area; therefore, this mega-landslide has been named the Church Mountain Sturzstrom (CMS). The CMS deposit is approximately 9 km in length, averages about 1 km in width, and has an estimated volume of 3 [times] 10[sup 8] m[sup 3]. Characteristics of the morphology and stratigraphy of the CMS deposit are suggestive of a sturzstrom origin, and may be indicative of sturzstrom elsewhere in the world. The overall stratigraphy of the deposit mimics the stratigraphy of the source area. The deposit is very compact, poorly sorted, matrix supported, and composed of highly angular clasts. Over steepening of the mountain due to glacial erosion may have contributed to the cause of failure, although the age of the CMS is at least 7,000 years younger than deglaciation. Four trees were C[sup 14] dated, yielding ages of about 2,700 B.P. for the CMS. Several other mega-landslides have been identified within 5--30 km of the CMS. The close proximity of these mega-landslides to the CMS suggests the possibility that they may have been triggered by an earthquake, although the ages of the other slides are currently unknown. The age of the CMS correlates approximately with age ranges of co-seismic events occurring along the west coast of Washington, further suggesting the possibility of an earthquake triggering mechanism.
- OSTI ID:
- 5291284
- Report Number(s):
- CONF-9305259-; CODEN: GAAPBC
- Journal Information:
- Geological Society of America, Abstracts with Programs; (United States), Vol. 25:5; Conference: 89. annual meeting of the Cordilleran Section and the 46th annual meeting of the Rocky Mountain Section of the Geological Society of America (GSA), Reno, NV (United States), 19-21 May 1993; ISSN 0016-7592
- Country of Publication:
- United States
- Language:
- English
Similar Records
Geomorphology and failure history of the earthquake-induced Farmington Siding landslide complex, Davis County, Utah
Landslides caused by the Mw7.8 KaikÅura earthquake and the immediate response