---}Answer the following questions briefly:---
• What is a rock?
• What are fossils?
• Why is it not possible for us to go to the Centre of the earth?
• Distinguish between extrusive and intrusive igneous rocks.
• How are metamorphic rocks formed?
• Mention any 2 uses of rock.
• What are sediments?
• Give reasons why sedimentary rocks are formed from sediments?
• Give reasons why limestone is changed into marble.
• What is lava?
Answers
Answer:
rock is any naturally occurring solid mass or aggregate of Minerals.
fossile is any preserved remains or trace of any once living thing from a past geological age.
it is not possible for us to go to the center of earth because the temperature and pressure increase enormously as we go deeper and deeper inside the earth.
Rocks are used in construction, used for manufacturing substances.
Sedimentation is the tendency for particles in suspension to settle out of the fluid in which they are entrained and come to rest against a barrier.
lava is hot liquid rock that comes out of a mountain with an opening in the top of volcano.
Explanation:
1). A rock is any naturally occurring solid mass or aggregate of minerals or mineraloid matter. It is categorized by the minerals included, its chemical composition and the way in which it is formed. Rocks are usually grouped into three main groups: igneous rocks, metamorphic rocks and sedimentary rocks.
2). A fossil is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved in amber, hair, petrified wood, oil, coal, and DNA remnants.
4). The two main categories of igneous rocks are extrusive and intrusive. Extrusive rocks are formed on the surface of the Earth from lava, which is magma that has emerged from underground. Intrusive rocks are formed from magma that cools and solidifies within the crust of the planet.
6). Rocks are used for many purposes but some of them that we can see in our daily life are cited below :
Making Cement (Limestone) (Sedimentary Origin)
Writing (Chalk) (Sedimentary Origin)
Building Material (Sandstone) (Sedimentary Origin)
Bath Scrub (Pumice) (Igneous Origin)
Kerb Stone (Granite) (Igneous Origin)
7). Sediment is solid material that is moved and deposited in a new location. Sediment can consist of rocks and minerals, as well as the remains of plants and animals. ... Erosion is the removal and transportation of rock or soil. Erosion can move sediment through water, ice, or wind.
5). Metamorphic rocks started out as some other type of rock, but have been substantially changed from their original igneous, sedimentary, or earlier metamorphic form. Metamorphic rocks form when rocks are subjected to high heat, high pressure, hot mineral-rich fluids or, more commonly, some combination of these factors.