Death Valley, Owens Valley Fault Scarp, and Owens River Gorge
May 14, 2005
Today we visited Death Valley California. The thing that I enjoyed most about Death Valley was the large alluvial fans running from the surrounding peaks. Alluvial fans form in Death Valley when strong rains rush down the mountainside. When the strong rains rushes down the mountain they create mudflows that sweep up particles of rock and deposit them at the bottom of the mountains in a fan shape. The alluvial fan deposits are very unsorted; they can range from small grains of sand to large boulders. The picture below this entry shows a small alluvial fan and as you can see, the parking lot is small compared to the fan. Can you give me a reason why alluvial fans form in dry areas? If you would like the answer to the question above ask and I will post the answer.
May 15, 2005
Our May 15 stop was at the Owens valley fault, which is located east of the Sierra Nevada Mountains. The Owens valley fault is a horst and graben fault. Horst and graben faults occur when there is stretching in the land. When the land is stretched, the land in the middle drops down and two blocks remain above the lower block. The higher blocks are called horsts and the lower blocks are called grabens. The Owens valley fault is a good example of a horst and graben fault, but it also has strike slip motion. Strike slip motion is horizontal motion. If you have trouble, visualizing these two types of motion I have pictures below that show the motion.
The pictures above were taken from: www.leeric.lsu.edu/ bgbb/4/graben_horst.gif and
www.consrv.ca.gov/.../ images/strike-c.gif
May 16, 2005
We stopped at Owens River Gorge today. Owens River Gorge is an area where there are large volcanic deposits. We found pumice, which is a frothy rock with many air bubbles within the rock. Pumice has these air bubbles because there is a lot of gas present, and when the gas tries to rise in the lava does so in tiny bubbles; and when the lava hardens, it preserves the tiny air bubbles. If anyone has any questions about pumice post, your question and I will answer it.
Today we visited Death Valley California. The thing that I enjoyed most about Death Valley was the large alluvial fans running from the surrounding peaks. Alluvial fans form in Death Valley when strong rains rush down the mountainside. When the strong rains rushes down the mountain they create mudflows that sweep up particles of rock and deposit them at the bottom of the mountains in a fan shape. The alluvial fan deposits are very unsorted; they can range from small grains of sand to large boulders. The picture below this entry shows a small alluvial fan and as you can see, the parking lot is small compared to the fan. Can you give me a reason why alluvial fans form in dry areas? If you would like the answer to the question above ask and I will post the answer.
May 15, 2005
Our May 15 stop was at the Owens valley fault, which is located east of the Sierra Nevada Mountains. The Owens valley fault is a horst and graben fault. Horst and graben faults occur when there is stretching in the land. When the land is stretched, the land in the middle drops down and two blocks remain above the lower block. The higher blocks are called horsts and the lower blocks are called grabens. The Owens valley fault is a good example of a horst and graben fault, but it also has strike slip motion. Strike slip motion is horizontal motion. If you have trouble, visualizing these two types of motion I have pictures below that show the motion.
The pictures above were taken from: www.leeric.lsu.edu/ bgbb/4/graben_horst.gif and
www.consrv.ca.gov/.../ images/strike-c.gif
May 16, 2005
We stopped at Owens River Gorge today. Owens River Gorge is an area where there are large volcanic deposits. We found pumice, which is a frothy rock with many air bubbles within the rock. Pumice has these air bubbles because there is a lot of gas present, and when the gas tries to rise in the lava does so in tiny bubbles; and when the lava hardens, it preserves the tiny air bubbles. If anyone has any questions about pumice post, your question and I will answer it.