Rock Around America!

Here are some famous monuments around America made from rock

Mt. Rushmore

pres--washington--jefferson--t_3770.jpg Mt. Rushmore is a very famous monument of 4 former American presidents carved into the face of a mountain. The monument is in Keystone, South Dakota. The 4 presidents are George Washington, Thomas Jefferson, Theodore Roosevelt and Abraham Lincoln. The memorial covers 5.17 km2 and is 1,745m above sea level.

The monument is made from Granite, which is an intrusive igneous rock, which means that it cools slowly under the earths surface. Sometimes the magma erupts onto the surface making a rock called Rhyolite.

**__The Grand Canyon__**

external image grand-canyon-south-rim_466.jpg

The Grand Canyon is a steep sided canyon that has been carved by the Colorado River in the state of Arizona. The Canyon is 446 km long, 29km wide and its depth is 1,800 metres. The Grand Canyon has 10 layers of different rock. Most of the layers are sedimentary. Starting at the bottom the layers are.. Vishnu Schist, Tapeats Sandstone, Bright Angel Shale, Mauv Limestone, Redwall Limestone, Supai Group, Hermit Shale, Coconio Sandstone, Toroweap Formation and Kaibab Limestone.

Washington Monument

external image Washington_Monument_Dusk_Jan_2006.jpgThe washington Monument was built to commemorate the first U.S. President, George Washington. The monument is made from Marble, Granite (igneous) and Bluestone Gneiss. Which means that most of the monument is Metamorphic( the Granite and Bluestone Gneiss). Metamorphic means that Igneous rock sets and then gets heated up and changes the appearance of the rock. The Washingtonn Monument is the worlds tallest stone structure and the worlds tallest obelisk. It stands at a height of 555 feet and 5 1/8 inches.