Sutter Buttes, California

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

Sutter Buttes, CA The Sutter (or Marysville) Buttes rise with astonishing suddenness out of the Sacramento Valley. They are the only significant outcrops in the entire valley.

The Buttes are not just unique, they are remarkably steep. They consist of rhyolites and andesites about 1.5 million years old.
Given that some of the large Cascade Range stratovolcanoes are over a million years old, it is clear these were never in the same class, in size or longevity. They were probably more like the Mono Craters, a cluster of small and relatively short-lived vents.

Sutter Buttes, CA

Most of the outcrops themselves are on private land and not accessible without permission. However, road cuts and boulders along the public roads give a fairly clear picture of the geology.
Recently, large tracts of private land were acquired and hopefully this area will become a State park.

Sutter Buttes, CA

Fremont Was Here


	"In commemoration of Major General John C. Fremont, United States Army and his expedition encamped in the Sutter Buttes in this vicinity May 30, 1846 to June 8, 1846 while on a march from Klamath Lake to Sonoma where he represented the United States government during the Bear Flag Uprising which resulted in the acquisition of California from Mexico."

For those not familiar with California history, the Bear Flag Uprising was a coup byAmerican settlers during the Mexican War that proclaimed California a (briefly) independent republic. The flag became the present Californiastate flag. The bear on the flag is a grizzly bear, which ironically becameextinct in California shortly after 1900.

The Southern Buttes





	Stone walls were once numerous here, a startling sight since stone walls are not common in California.

Sutter Buttes, CA

The panorama above shows the resistant volcanic necks at right and the outward-dipping apron of lahars, flows, and pyroclastic debris at left.

The Southwestern Buttes




	Rock pile of volcanic boulders.

Sutter Buttes, CA

The panorama above shows the resistant volcanic necks in the distance flanked on both sides by their outward-dipping apron of lahars, flows, and pyroclastic debris.

The Western Buttes





	Below: views of the flat Sacramento River valley looking west.

The Northwestern Buttes






	A number of properties in this area make use of the abundant volcanic boulders for stone walls.

Rock Units of the Buttes

Cretaceous


	Small windows of Cretaceous sandstone occur in the Buttes (above) Left: doming of the underlying sedimentary units by the volcanic uplift created natural gas traps and natural gas wells are located around the buttes. One can be seen at lower left of the photo.

Tertiary

	Tertiary gravels occur in places on top of the Cretaceous.
	The gravel here is clearly not derived from the local lithology. The sandy unit underlying the gravel (below) may be Tertiary or may be Cretaceous in part.

Pleistocene Volcanic Rocks

	A lahar on the southwestern flank of the buttes
	Left and below: road cuts in the volcaniclastic apron of the buttes. Road cuts like these are best seen along the western side of the buttes.

	Left and below: roadside boulders allow frequent opportunities to sample the volcanic rocks, which seem to be uniformly coarse porphyritic rhyolites.

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Created 7 April 2003, Last Update 09 June 2020

	The Sutter (or Marysville) Buttes rise with astonishing suddenness out of the Sacramento Valley. They are the only significant outcrops in the entire valley.
	The Buttes are not just unique, they are remarkably steep. They consist of rhyolites and andesites about 1.5 million years old. Given that some of the large Cascade Range stratovolcanoes are over a million years old, it is clear these were never in the same class, in size or longevity. They were probably more like the Mono Craters, a cluster of small and relatively short-lived vents.


	Most of the outcrops themselves are on private land and not accessible without permission. However, road cuts and boulders along the public roads give a fairly clear picture of the geology. Recently, large tracts of private land were acquired and hopefully this area will become a State park.