Answer:
During the 1960's the disclosure of enormous gas and oil fields in Alaska accelerated the change of most coal framework to other petroleum products. During this period Usibelli Coal Mine bought the Suntrana mine and the mining activities in the Matanuska coal fields stopped activity.
I think the correct answer from the choices listed above is the second option. An example of folded mountains can be seen in the Alps in Europe. <span>Fold mountains are mountains formed mainly by the effects of folding on layers within the upper part of the Earth's crust. Hope this answers the question.</span>
Canadian shield is composed of Precambrian rocks that cover 2.8 million square miles.
Answer:
uwuqgwhqjqjwjwjqjwhahajwj
Explanation:
snqhqghqqjkqkshshgwuwiqiwhqjqkanbsbanamakw
i. Using fossil evidences
ii. Similar rock lithologies at the edges of continent
iii. Climate clues
iv. Fitting of the continents into a puzzle
v. Sea floor spreading
Explanation:
Pangea was a super-continent on the earth which formed about 330 million years ago during the Paleozoic and began breaking up during the early Mesozoic, about 175 million years ago.
Most of the present day continents formed as a result of the separation of the Pangea in the early Mesozoic.
The first scientist to propose the existence of this super-continent was Alfred Wegener in 1912. He suggested the continental drift hypothesis to explain the separation of the land masses.
Today, the theory has been revised to the theory of plate tectonics which provides a better mechanism to understand the drifting of the continents.
Here are some of the evidences to support the existence of Pangea;
- Using fossil evidences: Mesosaurus, a reptile animal that lived during the Permian, was found in both South America and Southern Africa. Since this animal could not swim nor fly, only a jointed landmass could have made them present in both continents.
- Similar rock lithologies at the edges of continents: rock formations at the Western edge of Africa and South - Eastern part of Brazil matches with one another and have been believed to be once joined together.
- Climatic clues such as glacial tills that are confined to temperate and polar regions have been found in tropical regions.
- Wegener fitted the present day continent into a giant supercontinent and this provided a visual support for his claim.
- Evidences from sea floor spreading revealing magnetic reversals at divergent margins suggests the prevalence of plate tectonics i.e moving plates on earth.
This among many other evidences underscores the existence of a supercontinent called Pangea.
