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“Bite-Size Bits of Local, National, and Global History”
“Bite-Size Bits of Local, National, and Global History”
Calistoga in Napa County, California — The American West (Pacific Coastal)
 

Petrified Forest

 
 
Petrified Forest Marker image. Click for full size.
By James King, May 18, 2016
1. Petrified Forest Marker
Inscription. The petrified forest, dating from the Eocene Period, is the only known example of a petrified forest in California. Its size, scope and variety of petrification is unique in the world. Opalized wood, obsidian, quartz crystal, petrified coral and fossilized insects number among its wonders.
 
Erected 1978 by California State Department of Parks and Recreation with Ollie Orre Bockee, Jeanette Orre Hawthorne, and Davida Conway. (Marker Number 915.)
 
Location. 38° 33.344′ N, 122° 38.305′ W. Marker is in Calistoga, California, in Napa County. Marker can be reached from Petrified Forest Road 0.7 miles east of Porter Creek & Calistoga Roads. Touch for map. The marker is at the front of the visitor center, on the right. Marker is at or near this postal address: 4100 Petrified Forest Road, Calistoga CA 94515, United States of America.
 
Other nearby markers. At least 8 other markers are within 4 miles of this marker, measured as the crow flies. A different marker also named Petrified Forest (within shouting distance of this marker); To Commemorate..."Petrified Charlie" (within shouting distance of this marker); Pioneer Cemetery (approx. 3 miles away); Calistoga Sam Brannan Center
Petrified Forest Monument image. Click for full size.
By James King, May 18, 2016
2. Petrified Forest Monument
Visitor Center in the background
(approx. 3 miles away); Calistoga City Hall (approx. 3.6 miles away); Mount View Hotel (approx. 3.6 miles away); Calistoga Depot (approx. 3.7 miles away); Oat Hill Mine Road (approx. 4 miles away). Touch for a list and map of all markers in Calistoga.
 
Also see . . .  Petrified Forest, Calistoga, California. What has been described as one of the finest examples in the world of an ancient forest is preserved here at the Petrified Forest, in Calistoga, California. This unique site at the gateway to the Napa Valley was created following a violent volcanic explosion 3.4 million years ago. Seven miles northeast of this property lies the remains of an extinct volcano that today we call Mt. St. Helena. The incredibly powerful blast knocked down the forest of now extinct Redwood trees (Sequoia Langsdorfii) in a SW-NE orientation. Thick layers of volcanic ash billowing from the volcano rapidly buried the trees, creating an anaerobic (oxygen deprived) environment which discouraged the presence of the bacteria that decompose organic material. The thousands of years following the event were characterized by the formation of mineral-rich
A Story of Petrification image. Click for full size.
By James King, May 18, 2016
3. A Story of Petrification
Trees do not "turn to stone" in the literal sense of the word. Many years ago a forest grew here. It was covered by ashes and mud from an active volcano. Water seeped down through this dust, carrying volcanic ash. Gradually the wood was replaced by the silica, in many cases cell for cell. So perfectly was this accomplished that very thin sections of the petrified wood can be studied microscopically and their structure determined. This process of petrification took a long time and gradually the mud and ash deposited ages ago were eroded away.
water which percolated through the ashy deposits, saturating the pores of the organic tissues of the Redwoods with silica, moving it through the cellular spaces. During this process the saturated water evaporated, and the excess minerals were deposited in the cells and tissues, creating a three-dimensional fossil through the process of permineralization, and perfectly presevering even the most minute detail of the wood...
(Submitted on February 25, 2017, by James King of San Miguel, California.) 
 
Categories. EnvironmentHorticulture & ForestryPaleontology
 
The White Rock... image. Click for full size.
By James King, May 18, 2016
4. The White Rock...
...at your feet is volcanic ash composed of sparkling glass shards and fine particles of volcanic dust. Silica is present in molecular form which is carried down by water through the ash toward the buried forest. Orange streaks and clusters present are concretions of iron.
The Giant - Length 60 ft., Width 6 ft. image. Click for full size.
By James King, May 18, 2016
5. The Giant - Length 60 ft., Width 6 ft.
These coastal redwoods fell like matchsticks in the direction of flow from a volcanic explosion.
The source of the blast came from behind the present-day Mt. St. Helena, seven miles to the northeast.
A blanket of volcanic ash covered these trees for several million years. The ground during this time became saturated with water containing dissolved silicon and oxygen or silica from the overlying ash.
The molecules of silica replaced the molecules of wood, turning wood to solid silica, quartz and stone. - From a trailside informational sign
The Monarch or "Tunnel Tree" image. Click for full size.
By James King, May 18, 2016
6. The Monarch or "Tunnel Tree"
Exposed length - 105 feet
Diameter - 6 feet
Species - California Coastal Redwood
Discovered - 1919
 
 
Credits. This page was last revised on February 27, 2017. This page originally submitted on February 25, 2017, by James King of San Miguel, California. This page has been viewed 349 times since then. Photos:   1, 2, 3, 4, 5, 6. submitted on February 25, 2017, by James King of San Miguel, California. • Syd Whittle was the editor who published this page.
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