Mount Saint Helens

Steven Dutch, Professor Emeritus, Natural and Applied Sciences, University of Wisconsin - Green Bay

Data for Mount Saint Helens is somewhat ambivalent. The topography available online from the U.S. Geological Survey dates from 1981 and shows changes due to the eruption. But all the other data layers - hydrography, roads, and so, date from 1978! Thus the data show the pre-eruption glaciers, outline of Spirit Lake, and the now-buried course of old state highway 504. On the maps above, the buried highway is dark purple, new lakes are light blue and the debris flow is light brown. Post-eruption data from U.S. Forest Service maps.

Mt. St. Helens 1994 October 28, 1994

North Entrance: Randle to Goat Mountain

Mt. St. Helens 1994 The plan was simple: drive south from Randle via Goat Mountain, Ryan Lake and Norway Pass to Windy Ridge.
Mt. St. Helens 1994 The first view of the blast area is standing but dead trees on the fringe.
Mt. St. Helens 1994 Mt. St. Helens 1994
Mt. St. Helens 1994 Mt. St. Helens 1994
Mt. St. Helens 1994

The Best Laid Plans

Mt. St. Helens 1994 By the time we were at Goat Mountain it was obvious that fall had progressed into winter. Here we are definitely within the blast zone.
Mt. St. Helens 1994 Mt. St. Helens 1994
Mt. St. Helens 1994 Below: it became increasingly obvious we were not going to get in this way.
Mt. St. Helens 1994 Mt. St. Helens 1994

Bear Meadow

Mt. St. Helens 1994 Okay, go to plan B. Go in through Bear Meadow and hope for improved weather. Of course, we can't see Mount St. Helens today, but we can perhaps do some of Day 2's stops. Left is undisturbed timber at Bear Meadows, below are standing dead trees on the fringes of the blast zone.
Mt. St. Helens 1994 Mt. St. Helens 1994
Mt. St. Helens 1994  

Clearwater Creek Canyon

Mt. St. Helens 1994 On a clear day this is a truly wonderful view. Clearwater Creek valley is one of the finest textbook glacial valleys anywhere. The blast moved down the west (right) flank of the valley and spilled across the floor, but not up the opposite side. The blast was mostly directed north, and here only a small portion of the pyroclastic flow spilled over the intervening ridges. By the time it got here it had lost most of its momentum and density.
Mt. St. Helens 1994 Mt. St. Helens 1994
Mt. St. Helens 1994 Mt. St. Helens 1994
Mt. St. Helens 1994  

Miners' Car

Mt. St. Helens 1994 Two miners were in their cabin here when the blast hit. Their car, rusted and burned out, is still here.
Mt. St. Helens 1994 Mt. St. Helens 1994
Mt. St. Helens 1994 Mt. St. Helens 1994
Mt. St. Helens 1994 Mt. St. Helens 1994

Harmony Basin

Mt. St. Helens 1994 The Harmony Basin overlook.

Below: looking east from the ridge.
Mt. St. Helens 1994 Mt. St. Helens 1994
Mt. St. Helens 1994 Harmony Basin is a valley leading to the far north end of Spirit Lake. All the trees were leveled by the blast and those at the bottom of the valley were swept up by the wave after the big landslide hit Spirit Lake.

Left and below: General views of Harmony Basin.
Mt. St. Helens 1994 Mt. St. Helens 1994
Mt. St. Helens 1994 Mt. St. Helens 1994
Mt. St. Helens 1994 Mt. St. Helens 1994
Mt. St. Helens 1994 Mt. St. Helens 1994
Mt. St. Helens 1994 Mt. St. Helens 1994
Mt. St. Helens 1994 Below: Old Mt. St. Helens pumice layers.
Mt. St. Helens 1994 Mt. St. Helens 1994
Mt. St. Helens 1994  
Mt. St. Helens 1994  
Mt. St. Helens 1994 Left and below: the wave carried timbers up the valleys and piled up a jumble of timber at the high water mark.
Mt. St. Helens 1994 Mt. St. Helens 1994
Mt. St. Helens 1994 Mt. St. Helens 1994
Mt. St. Helens 1994 Mt. St. Helens 1994
Mt. St. Helens 1994 Left: timbers resting on old Mt. St. Helens pumice. Generally the older the pumice, the more it oxidizes and the deeper the yellow or orange color.

 

Spirit Lake

Mt. St. Helens 1994 Distant view of the log raft on Spirit Lake.
Mt. St. Helens 1994 Mt. St. Helens 1994

Glacial Geology

Mt. St. Helens 1994 This area was glaciated during the Illinoisan ice advance, the next to last ice age. It's very unusual to be able to see Illinoisan glacial features.
Mt. St. Helens 1994 Mt. St. Helens 1994
Mt. St. Helens 1994 Mt. St. Helens 1994
Mt. St. Helens 1994 Glacial striations
Mt. St. Helens 1994 Porphyritic dacite

The Floating Log Raft

Mt. St. Helens 1994 The weather was as thoroughly rotten as it looks. These are logs that were knocked down by the blast, picked up by the wave created when the landslide hit Spirit Lake, then carried back into the lake.
Mt. St. Helens 1994 Mt. St. Helens 1994
Mt. St. Helens 1994 Mt. St. Helens 1994
Mt. St. Helens 1994 Mt. St. Helens 1994

Windy Ridge

Mt. St. Helens 1994 Even by the standards of a place called Windy Ridge, it was windy. Actually it was a blizzard. The faint horizontal texture on the ground is scour from the 1980 pyroclastic flow.
Mt. St. Helens 1994 Downed timber on Windy Ridge.
Mt. St. Helens 1994 The south end of Spirit Lake. The low slope on the far side is the 1980 landslide.

Out the Way We Didn't Come In

Mt. St. Helens 1994 Mt. St. Helens 1994
Mt. St. Helens 1994 Mt. St. Helens 1994
Mt. St. Helens 1994 Mt. St. Helens 1994
Mt. St. Helens 1994  
Mt. St. Helens 1994 Mt. St. Helens 1994  
Mt. St. Helens 1994 Mt. St. Helens 1994
Mt. St. Helens 1994 Mt. St. Helens 1994  

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Created 15 April 2003, Last Update 08 June 2020