There are three main types of rock: igneous rock, metamorphic rock, and sedimentary rock. Almost all fossils are preserved in sedimentary rock. Organisms that live in topographically low places (such ...

The basalt which makes up the Giant’s causeway is an igneous rock. Sedimentary rocks are formed by small rock pieces which are transported by rivers and laid down in layers. Chalk is a ...

Relative dating to determine the age of rocks and fossils Geologists have established a set of principles that can be applied to sedimentary and volcanic rocks that are exposed at the Earth's ...

What Was Happening on Earth at This Time The Precambrian is the earliest of the geologic ages, which are marked by different layers of sedimentary rock. Laid down over millions of years ...