Monday, August 31, 2015

CBS Sunday Morning - Geology in the movies

Here is a recent story from CBS Sunday morning talking about the new film San Andreas. The Sunday Morning team interview USGS seismologist Lucy Jones about what is and what isn't real. Very similar to my Geological Movie Reviews I had worked on.

Monday, August 10, 2015

Geology of the National Parks Through Pictures - Zion National Park

My next post about the Geology of the National Parks Through Pictures is a fairly local park and a revisited park. 

You can find more Geology of the National Parks Through Pictures as well as my Geological State Symbols Across America series at my website


Obligatory entrance sign

 View down the Lower Fork Virgin River from the bridge that leads to the Emerald Pools Trail. Most of the visible cliff rocks within the canyon are the Navajo Formation. The Navajo Formation is a rock unit that used to be a vast desert that crossed the middle of North America.

 Nice view up the cliff along the Emerald Pools Trail.

 The tired hiker on the trail.

 Under one of the many waterfalls along the trail.

The Navajo Formation is actually prehistoric dunes. As the wind blows in a desert, the sand gets blown into piles called dunes. Eventually the sand gets blown over the top of the dunes. As more and more sand gets blown over the top, eventually the dune actually moves. The layers seen above, called cross-beds, are produced by this movement of the sand over the top and down the side of the dune. The side the sand slides down is called the slipface.

 View out of the Emerald Pools Trail into the main valley. When sandstone gets lithified (turned into rock) it produces a really hard rock that is difficult to erode. So when a river does erode a sandstone, the rocks not directly next to the river can form steep cliff faces, as seen within the Zion Canyon.

 Another view into the main valley.

 View of the Three Kings

Towards the eastern edge of the park is some of the best cross-bedding in the park. 

Some more cross bedding.