Category Archives: Geology

New Book on Berryessa Snow Mountain National Monument

Slightly off-topic here, but there’s a new book for those interested in geology, history, ecology, and travel guides in California’s North Coast Ranges: Exploring the Berryessa Snow Mountain National Monument Region, written by Marc Hoshovsky, Bob Schneider, Peter Schiffman, and also me (Tim Messick). I mostly prepared the maps and other graphics in this lavishly illustrated volume.

It’s available now from Backcountry Press, here:
https://backcountrypress.com/book/exploring-the-berryessa-region/
(And you get a free eBook version when you purchase the paperback edition before February 1st, 2026.)

Cover art by Obi Kauffman

Copyright © Tim Messick 2025. All rights reserved

Strolling around Panum Crater

Panum Crater in Google Earth

Panum Crater (foreground) and Mono Craters as seen in
Google Earth, looking southeast.

Panum Crater

One frosty morning in late October I walked around the narrow rim of Panum Crater, just south of Mono Lake. This is the youngest volcanic feature in the Mono Basin, so if you love landscapes built by fire and carved by ice, I highly recommend this hike, but do it in cool weather or very early on a summer day.

Panum Crater

Panum Crater

Panum Crater is only about 670 ±20 years old (circa 1320s to 1360s AD) (Sieh and Bursik 1986). The initial eruption was of the “Plinian” type, where abundant gases escape from the rising magma, producing a massive plume and rain of volcanic ash that may continue for weeks. (This is the same type of eruption that occurred on a larger scale at Italy’s Mt. Vesuvius in 79 AD, burying Pompeii and Herculaneum—witnessed and later described by Pliny the Younger, hence the name “Plinian.”) After the plumes of gas and ash subsided, magma welled up within Panum Crater to form a jagged dome of obsidian and pumice. Some time after the Panum Crater event, more ash fell throughout the area from eruptions several miles farther south in the Inyo Craters area.

Panum Crater

What would it have been like to see, hear, and smell this eruption, to feel the earth shake before and during the eruption? There were certainly Native Americans living here at that time — in the Mono Basin, the Bodie Hills, Bridgeport and Adobe Valleys, and on down to Owens Valley. We don’t know what time of year the eruption occurred, but there could have been groups traveling over Mono Pass and along other routes to trade with neighboring tribes when the eruption began.

Panum Crater

Laylander (1998) speculated on how earlier (ca. 880 AD) and larger Plinian eruptions in the Mono Craters may have affected local witnesses: “Local consequences for human populations from the eruption can be imagined. The event may have directly caused some loss of life or frightened the surviving witnesses into leaving the Mono Basin. The decimation of plant and animal communities may have drastically reduced the resource value of the affected area for humans for some time.” (He goes on to consider whether “an occupational hiatus, followed by a return to pre-event conditions” could be detected in the archaeological record and whether the duration of this hiatus could be estimated archaeologically. He concludes that “a hiatus of as much as a century is not likely to be detectable in the archaeological record” using hydration dating of artifacts, unless the sample size is “very large.”)

Panum Crater

Panum Crater

Banded obsidian and pumice atop the dome.

Panum Crater

Panum Crater

Panum Crater

Panum Crater is not quite the youngest cinder cone in California — that distinction may belong to Cinder Cone in Lassen Volcanic National Park, which erupted about 300 years later, circa 1650. And Lassen Peak itself erupted last in 1915.

References:
Laylander, D. 1998, Cultural Hiatus and Chronological Resolution: Simulating the Mono Craters Eruption of ca. A.D. 880 in the Archaeological Record, Proceedings of the Society for California Archaeology 11:148-154.

Sieh, K. and M. Bursik 1986. Most recent eruption of the Mono Craters, eastern central California. Journal of Geophysical Research, 91(B12): 12,539–12,571.


Copyright © Tim Messick 2020. All rights reserved.
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Effects of the Earthquake near Bodie

I was in Bodie the first week it was open to the public since the magnitude 5.7 earthquakes near Nine Mile Ranch in Fletcher Valley that caused some damage here and startled people through much of the Eastern Sierra region on December 28, 2016. There is visible damage to the walls or contents of several buildings. There’s also an issue with the water system.

Perhaps most serious is damage to the back wall of the DeChambeau Hotel. Some bricks fell away from the top of the wall and other cracks are visible lower in the wall.

DeChambeau Hotel

Brick Wall


Inside the DeChambeau Hotel, bottles on the bar fell over.

Bar

Next door in the IOOF building, many of the old bottles that were neatly stacked in a display case fell to the floor and broke.

Bottles


In the morgue, an open coffin toppled off the back of the table on which it was resting. The lid came off another one standing to its left.

Morgue

May 2017

Morgue, 2007

October 2007


The Boone Store lost one of the large front windows, now temporarily covered with plywood. Inside, the hat-wearing dress form looks a little worse for her exposure to the elements.

Boone Store

Boone Store

May 2017

Boone Store

June 2013


In the Cain House, bottles toppled from the display shelves inside the front windows.


Over on the northeast side of the Bodie Hills, in Fletcher Valley, the stone walls the historic building at Nine Mile Ranch (the oldest intact building in Mineral County!) were severely damaged. This building is only a mile from the epicenters of the largest quakes.

Nine Mile Nine Mile

 


Copyright © Tim Messick 2017. All rights reserved.
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