Topic: Sand spouts - mud volcanoes

[Mike]

Watched a fascinating show on Discovery Magazine channel the other day which discussed earthquakes and geologists searching for fault lines and the like.  Unlike pyroclastic flows and lava, they have discovered in a mountanous area in the US of what they described as 'sand spouts' that have literally covered an area several metres deep as opposed to actual lava induced flows.

They described it similar to when you walk on the beach or in a mud sodden area and tramp down with your feet in one area and compress the mud/sand and you notice how the water rises to the top and then you find a spot near you that shows a small 'fountain' of water/sand coming up.  Imagine that on a volcanic scale as the boiling water and sand is thrust skyward.  Areas of volcanic history and tectonic plate shifts with soils of mostly sand and and soil showed layers of sand which had been forced upward and over soil as the plates moved and the water table also found an escape route.  Found these links of many it seems which has some info http://www.volcanolive.com/baiyanggou.html andthis http://volcanoes.usgs.gov/Products/Pglossary/MudVolcano.html

Has anyone else heard of these things?

Mike

[Harley Pearman]

Sand Spouts - Mud Volcanoes - 19/1/2008

Mike

This is interesting. Would the research be undertaken at Yellowstone National Park (Wyoming) or Mono Craters (California). If so I have been to such places where this could occur.

Mono Lake - There is a volcanic island situated in the middle of Mono Lake crater being a caldera crater sitting atop of magma plume below. You cannot get to the island but the island in the middle is composed of sand and fine volcanic material such as ash or pumice where this could potentially occur. I photographed a spectacular dust devil crossing this volcanic island when I was there which is why I have suggested this.

Mono crater is situated on the Eastern side of the Sierra Nevada some 2,200 metres in elevation and this area is riven with volcanic activity and fault lines.

The other location would be yellowstone.

Yellowstone: This is a supervolcano, a caldera with a magma chamber measuring 80 km x 40 km and 8 km thick. This park contains a majority of the world's geysers, mud volcanoes and fumeroes. There are numerous walking trails throughout that are signposted telling visitors to keep to the trails otherwise wandering off them could result in:-

a) Adversely affecting a geyser (In a similar fashion to what you say).
b) Collapsing through the ground.

Given the soil structure in parts of Yellowstone composed of sandy, ash and fine material, pressure exerted in one area does in fact force upward hot water or mud in a spring nearby. It is best to keep off these areas.

The warning signs specify this, especially around the Norris Geyser Basin.

Harley Pearman