the black hills are an example of which type of mountain building?
a. uplifted mountains
b.fault-block mountains
c.volcanic mountains
d. oceanic mountains
To determine which type of mountain building the Black Hills are an example of, we need to understand the different types of mountains and how they are formed.
a. Uplifted mountains: These mountains form when tectonic forces push up crustal rocks due to compression, folding, or faulting. The rocks are usually lifted without significant displacement along faults. An example of this type of mountain is the Appalachian Mountains on the east coast of the United States.
b. Fault-block mountains: These mountains are formed when tectonic forces cause blocks of rock to move along faults. One block is elevated while the other drops down, creating mountains. The Sierra Nevada in California is an example of fault-block mountains.
c. Volcanic mountains: These mountains result from volcanic activity where molten rock (magma), ash, and other materials are expelled from a volcano and accumulate to form a mountain. Examples of volcanic mountains include Mount Fuji in Japan and Mount St. Helens in the United States.
d. Oceanic mountains: These mountains form along mid-ocean ridges where tectonic plates spread apart and magma rises to create new oceanic crust. The Mid-Atlantic Ridge is an example of an oceanic mountain.
In the case of the Black Hills, they are best classified as uplifted mountains (option a). The Black Hills in South Dakota and Wyoming were formed through a combination of uplift and erosion caused by tectonic forces. They are primarily composed of igneous and metamorphic rocks that were pushed up and exposed over millions of years.
So, the correct answer is: a. uplifted mountains.