Shastina and the Mount Shasta Landslide, California

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

California's magnificent volcano, Mount Shasta, has a satellite (or parasitic) cone on its western flank called Shastina. If Shastina were a solitary peak, it would still be the third highest peak in the Cascade Range with an elevation of 12,330 ft (3,758 m). However, it is overshadowed by Mount Shasta, nearly 2000 feet higher.

Shastina has a very fresh looking crater and is obviously recently active. The small hills in the distance beyond Shastina are great blocks that slid downhill in a huge landslide about 300,000 years ago. Despite their impressive size, volcanoes are weak piles of lave flows, mudflows, and ash layers, and are weakened further by corrosive gases from the magma. After Mount Saint Helens collapsed in 1980, geologists began to wonder how often collapses like that happened. The answer is, quite often. The hilly terrain northwest of Mount Shasta was soon recognized as one such landslide.

It is probably no accident that Shastina is located in the direction of the slide. After the volcano collapsed, it was easier for magma to escape through the broken flank of the volcano than through the old summit.

The snow patches on Shastina conceal a couple of tiny ponds that remain frozen until very late in the summer. Even in this picture, taken late in July, they are still covered with snow and ice.

Location of Mount Shasta:  41o 24' 33" N, 122o 11' 42" W. Location of Shastina:  41o 24' 33" N, 122o 13' 21" W.

Original Scene

(author's image)

Possible Coloring

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Created 19 February 2008, Last Update 15 January 2020