GENERAL GEOLOGY

Detailed explanation-1: -One group of small ones is called microfossils. Another group of even smaller fossils is called nannofossils and they require very powerful microscopes to be seen. Just by the name of the group, scientists can estimate how small the fossil will be before they ever even look at it.

Detailed explanation-2: -Most fossils “hide out” in sedimentary rock . When tiny bits of rocks and minerals (called sediment) join together over millions of years, they become sedimentary rock. Plants and animals that become sandwiched in this sediment eventually turn into fossils. Two examples of sedimentary rocks are sandstone and shale.

Detailed explanation-3: -Fossils usually occur in sedimentary rocks. The molten material that forms igneous rocks would destroy the remains of living organisms. It is common to find fossils in low-grade metamorphosed sedimentary rocks, although the fossils are usually somewhat deformed or distorted.

Detailed explanation-4: -How can scientists use index fossils to determine the absolute age of rock layers in different parts of the world? an index fossil discovered in rock layers in different areas of the world indicates that the rock layers in these areas formed during the same time period.