The Rocky Mountains by

Geologic events The Rockies are composed exclusively of layered sedimentary rocks. These include limestone, dolomite, sandstone and shale, among others. Sedimentary rocks cover approximately 75% of the worlds surface. Regular sedimentation has been shattered, older rocks lie on top of younger rocks. SOURCE: Mountainnature.com. Accessed 11/10/09.

Mountain Types The Rockies include Matterhorn mountains. Glaciers have scoured the peak. Other types of mountains are dogtooth, sawtooth, castellate, anticlinal, synclinal, and complex SOURCE: Mountainnature.com. Accessed 11/10/09.

Geologic Forces In some places the formation of the mountains ripped through to the magma, which pushed through the older rocks This is called an igneous intrusion of dacite porphyry. This one is called Tooth of Time in Northern New Mexico and was formed in the Tertiary Period of the Cenozoic era some million years ago SOURCE: Tooth of Time. Accessed 11/10/09.

Extent of the Rockies

The orogony that caused the Rockies moved from the ocean inland This mountain belt protects the craton which is called The Great Plains It affects the weather and helps much of the United States in its ability to produce large amounts of food It is formed by the tectonic plates thrusting the continental shelf inward toward the continental interior, producing giant thrust faults hundreds of miles long, as if one block of continental crust was simply pushed over the top of another SOURCE: Google Answers. Plate Tectonics-Rocky Mountains. Updated 3/26/03. Accessed 11/10/09.

The mountains themselves have unpredictable weather. Snowfalls end in June at the mountain peaks and start again in August. But the peaks also provide many valleys with good grazing land for horses and cattle and ensure water for the growth of plants and animals.

Dolomite rock is one of the sedimentary rocks that undergoes a significant mineralogical change after it is deposited. The process is not metamorphism, but something just short of that. (SOURCE:DOLOMITE. Updated Accessed 11/10/09) Limestone is a very common sedimentary rock of biochemical origin. It is composed mostly of the mineral calcite. (Source:Limestone. Updated 2009, accessed 11/10/09.) Sandstone is sand cemented together into rock. It is a clastic sedimentary rock. It is composed mostly of medium-grain sand.(SOURCE: About Sandstone. Accessed 11/10/09.) Shale is a claystone that is fissile, splitting in layers. Shale is usually soft and does not crop out unless harder rock protects it. (Source: Shale. Accessed 11/10/09.)

The Tooth rises from the valley floor creating a sheer vertical face unable to support substantial plant life. Both its pinkish-gray color and its unusual shape make it a particularly notable geological landmark. It was well-known among the overland traders on the Santa Fe Trail. The Tooth was formed when magma from the Earth's mantle rose through older rock layers via convection and slowly cooled. Over thousands of years, the older sedimentary rock eroded and left the harder igneous formation. The sedimentary rock acted as a mold for the intrusive magma, causing it to harden and cool where the sedimentary rock was strongest. ABOUT MY GEOLOGIC FEATURE

HOW DO WE KNOW THE AGE OF THE ROCKIES? The formation of the Rocky Mountain structures in late Cretaceous through Eocene time is that plate of oceanic lithosphere was underthrust horizontally along the base of the North American lithosphere. The horizontal components of the motion of this plate are known from paleomagnetism The edge of the region of flat slab can be estimated from reconstructed patterns of volcanism. (SOURCE: Peter Bird. Formation of the Rocky Mountains, Western United States: A Continuum Computer Model. 3/25/88. Accessed 11/10/09)

ROCKY MOUNTAIN CLIMATE VARIANCES From the Alpine Tundra (SOURCE: To high mountain lakes (SOURCE: mountains.3.html) And tree lines that go from pines to aspens (SOURCE:

Rocky Mountain Surprises To rivers flowing with water that was ice just hours before (SOURCE: And hidden cantons hiding Native American history. (Source: The Rockies provide some of the most interesting and exciting areas in the United States.