Answer:
Protostars are difficult to observe because they are surrounded by cocoons of gas and dust.
The igneous rocks are the basic material for the formation of the two other rocks types, the sedimentary and metamorphic rocks. These rocks are the first that form. They form from the magma that has cooled inside the crust, or by the lava flows on the surface. Over time, the weathering and erosion start to break them apart little by little, creating sediments from them. These sediments are the founding block for the formation of the sedimentary rocks. Once these sediments are exposed to certain temperatures and pressures they start to become compact again, which is made possible through the cementation process that keeps them together. As more and more sediments are merged together, the sedimentary rocks are formed, and they can come in multiple different types, sizes, shapes, as well as compositions, and structures.
Kuril island hope it helps
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.