Mountain Building

Folded Mountain

-compressional forces squeeze the rock layers from opposite sides causing it to buckle.

Folded Mountain

Ex.

Up-Warped Mountain

- crust is pushed upward by forces inside the earth.

Up-Warped Mountain

- crust is pushed upward by forces inside the earth.

Up-Warped Mountain

Ex.

Adirondak Mountains

Rockies

Rockies

Black Hills

Volcanic Mountain

-molten material reaches the surface through a weak area of crust and piles up, one layer on top of another to form a cone-shaped structure

Volcanic Mountain

Ex.

Moana Loa

Moana Loa – shield volcano

Mt. St. Helens

Mt. St. Helens

Vesuvius

Etna

Colima, Mexico

One day a man from a small village in Michoacán, Mexico was going out in his fields. Just then the ground nearby opened up a fissure. There was a greenish smoke and a smell of sulfur. Then the ground rose up 2 ½ meters high.

Paricutin exploded out of a cornfield about 200 miles west of Mexico City in early 1943, giving the modern world its first opportunity to witness the birth of a volcano. Within a year, the volcano's cinder cone reached 1,100 feet. Within two years, its slow-moving lava flows buried most of the town of Paricutin. The lava eventually covered about 10 square miles.

Paricutin, Mexico

Paricutin is not expected to erupt again. The village was rebuilt some distance away.

Fault Block Mountain

- huge tilted blocks separated from surrounding rock by faults.

Fault Block Mountain

- huge tilted blocks separated from surrounding rock by faults.

Fault Block Mountain

Ex.

Tetons

Sierras - California

Franklin Mts. - Texas

San Pedro Valley

Thirty miles south of Salt Lake City, near the mouth of Provo Canyon in Orem, Utah is an excellent example of fault block mountains. The north-south trending Wasatch Range extends throughout the center of Utah. The western flank of

the range is very steep and relatively straight, the result of displacement along the extensive and still-active Wasatch Fault. Summits along the crest of the range have elevations between 9,000 and 10,000 feet. The mountain-sized fault

blocks of this region developed in a fairly orderly fashion, breaking roughly at right angles to the westward direction of stress. As visible in this photo, the truncated spurs of the Wasatch Mountains provide evidence that movement on the

Wasatch fault is geologically recent.

California