Mount Multnomah is an invalidated hypothetical ancient
volcano
A volcano is a rupture in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface.
On Earth, volcanoes are most often found where tectonic plates are ...
postulated in a 1925 publication by geologist
Edwin T. Hodge. It was proposed to exist in central
Oregon
Oregon () is a U.S. state, state in the Pacific Northwest region of the Western United States. The Columbia River delineates much of Oregon's northern boundary with Washington (state), Washington, while the Snake River delineates much of it ...
at the present day location of the
Three Sisters region. It was estimated to have been around tall, and was believed destroyed in a fashion similar to
Mount Mazama
Mount Mazama (''Giiwas'' in the Native American language Klamath language, Klamath) is a complex volcano in the state of Oregon, United States, in a segment of the Cascade Volcanoes, Cascade Volcanic Arc and Cascade Range. Most of the mountai ...
's eruption resulting in what is now
Crater Lake
Crater Lake (Klamath language, Klamath: ''Giiwas'') is a volcanic crater lake in south-central Oregon in the western United States. It is the main feature of Crater Lake National Park and is famous for its deep blue color and water clarity. The ...
in southern Oregon.
In 1924, Hodge performed fieldwork around the area and concluded that the three adjacent volcanoes and their foothills were once part of a single giant volcano. His conclusion was bolstered by
oral history
Oral history is the collection and study of historical information about individuals, families, important events, or everyday life using audiotapes, videotapes, or transcriptions of planned interviews. These interviews are conducted with people wh ...
from the local
Warm Springs tribe, which recounted the massive eruption and collapse of the ancient peak:
The date of eruption that Hodge calculated using the
potassium-argon method was
25 million to 27 million years ago. This predates the earliest estimates of human presence in North America (see
Settlement of the Americas
The settlement of the Americas began when Paleolithic hunter-gatherers entered North America from the North Asian Mammoth steppe via the Beringia land bridge, which had formed between northeastern Siberia and western Alaska due to the lowering o ...
) and even the earliest known humans (see
Archaic Homo sapiens) by millions of years.
Years later, Howel Williams, then dean of Cascade volcanologists, concluded that each of the Three Sisters and their surrounding mountains were unique and did not represent remains of a single collapsed structure.
[ quoting Stephen L. Harris]
See also
*
Supervolcano
References
*
*
Cascade Range
Natural history of Oregon
{{Oregon-geo-stub