Mt. Shasta,CA  

Glass Mountain

 
   
   
 

Little Glass Mountain

Little Glass Mountain,CA  

 

  Little Glass Mountain,CA
 

 

  Little Glass Mountain, CA
 
             
        Little Glass Mountain
This is a most treacherous climb on pure glass
           

 

Glass Mountain from Medicine Lake caldera rim. USGS photo by Julie Donnelly-Nolan.
The most recent eruption occurred around 1,000 years ago when rhyolite and dacite erupted
at Glass Mountain and associated vents near the caldera's eastern rim. No field evidence has
been found to substantiate a report of an eruption in 1910.
Glass Mountain consists of a spectacular, nearly treeless, steep-sided rhyolite and dacite
obsidian flow that erupted just outside the eastern caldera rim and flowed down the steep
eastern flank of Medicine Lake Volcano. Ten additional small domes of Glass Mountain rhyolite
and rhyodacite lava lie on a N25degreesW trend to the north and one to the south.
The age of Glass Mountain and its preceding pumice deposits has been a matter of discussion
for some time. A radiocarbon dating age of 885+/-40 years before present (1990) was obtained
on a dead incense-cedar tree without limbs or bark that is preserved in the edge of one of the distal
tongues of the flow. The dated material consisted of a piece of exterior wood containing about 30
annual growth rings.
This age may be too old, because some of the outside of the tree is missing.
The tephra deposits that precede the flow and domes may be somewhat older but are constrained
to be less than about 1050 years before present (1990) by the Little Glass Mountain and Lassen Peak data.

Source: Wikipedia

 
       
 

Black Butte

Castle Crags

Castle Lake

Lava Tubes

McCloud Falls

Burney Falls

HedgeCreek Falls

Lake Britton

Lake Siskiyou

Mt. Shasta Ski Bowl

HedgeCreek Falls

Shasta Dam

Lake Siskiyou

Top of the Mountain

Squaw Valley Creek Trail

Wild Flowers at the top of Mt. Shasta

Views of Mt. Shasta from surrounding areas

North Weed Hwy and rest stop Leading to Weed

North View from Louis Road south

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