Known Geologic Events at Mount Rainier
The purpose of this page is to list all known, dated gelogic events at Mount Rainier, including lahars, debris flows, large rockfalls, large avalanches, rockfalls, and other events. This list is currently being compiled, so if you find errors or a missing event, please
let Scott know.
Database ID#: 82
Date: Wednesday, September 20, 2017
Location: Mount Rainier National Park
Glacier Name: None
Drainage Basin:
Event Type: Earthquake
Weather:
Varied, warm and dry to cool and wet
Season: N/A
Notes:
Over the last week more than 20 earthquakes have been located by the PNSN at Mount Rainier. In a typical week Mount Rainier experiences about two "located" earthquakes, so this represents a modest increase over background rates.
The seismicity uptick started late September 11 with a swarm of five earthquakes located 1-2 km to the southeast of the summit area. These earthquakes were shallow (up to 2 km above sea level), small (maximum magnitude was a M1.6), and in an area that has not had a lot of previously recorded seismicity. Beginning September 13, earthquakes were also detected about 1 km to the northeast and southeast of the summit, in areas where earthquakes typically occur at Mount Rainier. Depths for these events were 1-2 km below sea level, which is also typical for background seismicity at the volcano, and event magnitudes were small (maximum magnitude 1.2)
In total there have been 23 earthquakes since September 11, with event rates of up to eight located earthquakes per day. Although this is higher than the normal seismicity rates at Mount Rainier, it is not unprecedented. Over the past 10 years there have been three previous periods with similar or higher event rates (September 2009, April 2015 and May 2016). Current event rates are similar to those seen in April 2015 and May 2016, but are far smaller in rate, energy release, and total number of earthquakes than what was seen in September 2009, when a swarm featuring hundreds of located earthquakes occurred over a three-day period.
For the current swarm, earthquake location, depth, and size are all consistent with background seismicity; the only thing that is different is the event rate. These earthquakes are inferred by scientists to be caused by processes occurring in Mount Rainer's hydrothermal system.
THIS EVENT IS ONGOING AND LIKELY TO CHANGE.
http://www.morageology.com/earthquake_range.php?t0=1505433600&t1=1506297600&dt_length=50
Estimated Velocity:
Estimated Peak Flow:
Estimated Volume:
References:
S. Moran, personal communication.
Data references:
Beason, S.R., 2012, Small glacial outburst flood occurs on Mount Rainier - October 27, 2012: Unpublished National Park Service Science Brief, 3 p.
Beason, S.R., et al., in prep, Glacial outburst floods and debris flows from the South Tahoma Glacier, Mount Rainier National Park, Washington: August and September, 2015: National Park Service Natural Resource Report NPS/MORA/NRR-2015/XXX.
Copeland, E.A., 2010, Recent periglacial debris flows from Mount Rainier, Washington: M.S. Thesis, Oregon State University, 125 p.
Copeland, E.A., P.M. Kennard, A.W. Nolin, S.T. Lanscaster and G.E. Grant, 2008, Initiation of recent debris flows on Mount Rainier, Washington: A climate warming signal? American Geophysical Union Fall Meeting, San Francisco, CA.
Crandell, D.R., 1971, Postglacial lahars from Mt. Rainier volcano, Washington: U.S. Geological Survey Professional Paper 677, 75 p.
Donovan, K.H.M, 2005, An investigation into the 2003 Van Trump Creek debris flow, Mt. Rainier, Washington, United States of America: BSc Geological Hazards Thesis, University of Portsmouth (UK), 58 p.
Driedger, C.L. and A.G. Fountain, 1989, Glacier outburst floods at Mout Rainier, Washington State, USA: Anals of Glaciology, Vol. 13, 5 p.
Hodge, S., 1972, The movement and basal conditions of the Nisqually Glacier, Mount Rainier: Ph.D Thesis, Univeristy of Washington, xxx p.
Legg, N.T., 2013, Debris flows in glaciated catchments: A case study on Mount Rainier, Washington: M.S. Thesis, Oregon State University, 162 p.
Legg, N.T., A.J. Meigs, G.E. Grant and P.M. Kennard, 2014, Debris flow initiation in proglacial gullies on Mount Rainier, Washington: Geomorphology, Vol. 226, p. 249-260.
Richardson D., 1968, Glacier outburst floods in the Pacific Northwest: U.S. Geological Survey Professional Paper 600-D, D79-D86.
Samora, B., 1991, Chronology of flood events as noted in the superintendent's annual reports 1940-1991, Unpublished Internal Document, Mount Rainier National Park, WA, 13 p.
Scott, K.M., J.W. Vallance, and P.T. Pringle, 1995, Sedimentology, behavior, and hazards of debris flows at Mount Rainier, Washington: United States Geological Survey Professional Paper 1547, 56 p.
Vallance, J.W., C.L. Driedger and W.E. Scott, 2002, Diversion of meltwater from Kautz Glacier initiates small debris flows near Van Trump Park, Mount Rainier, Washington: Washington Geology, Vol. 30, No. 1/2, p. 17-19.
Vallance, J.W., M.L. Cunico and S.P. Schilling, 2003, Debris-flow hazards caused by hydrologic events at Mount Rainier, Washington: United States Geological Survey Open-File Report 2003-368, 4 p.
Walder, J.S. and C.L. Driedger, 1994, Geomorphic changed caused by outburst floods and debris flows at Mount Rainier, Washington, with emphasis on Tahoma Creek valley: U.S. Geological Survey Water-Resources Investigations Report 93-4093, 100 p.
Walder, J.S. and C.L. Driedger, 1994, Rapid geomorphic change caused by glacial outburst floods and debris flows along Tahoma Creek, Mount Rainier, Washington, USA: Arctic and Alpine Research, Vol. 26, No. 4, p. 319-327.
Walder, J.S. and C.L. Driedger, 1995, Frequent outburst floods from South Tahoma Glacier, Mount Rainier, USA: relation to debris flows, meterological origin and implications for subglacial hydrology: Journal of Glaciology, Vol. 41, No. 137, 11 p.