The beginning of the creation of the universe. This theory said it created space and energy and atoms began to form.
Geologic Time Scale: Phanerozoic
It wasn't until the ozone layer (red circle) developed to protect Earth from the Sun's UV rays for life to start on Earth. Before, Earth's atmosphere consisted mainly of nitrogen, water vapor and carbon dioxide. There was no oxygen.
Pangaea Plate Tectonics and Plate Boundaries
The Precambrian covers the Hadean, Archean and Proterozoic eras. After the planet cooled, crust and oceans formed. Eventually bacteria would do photosynthesis producing enough oxygen for plant and animal life to form. The Precambrian covers about 87% of Earth's history
This eon covers three major time spans: Paleozoic (541 million to 252 million years ago), Mesozoic (252 million to 66 million years ago), and Cenozoic (66 million years ago to the present) eras. During the Mesozoic era, the supercontinent, Pangea split apart.
Pangaea was a supercontinent on Earth. The Earth's crust consists of many tectonic plates. When they move, so do the continents, called continental drift. The moving plates can end up forming mountains, volcanoes and can cause earthquakes. A divergent boundary is when plates are moving apart and new crust is created. A convergent boundary is when plates above and below each other. And a transform boundary is when plates move against each other.
Fossils are the remains of once living animals or plants. Scientist use fossils to observe how life once was and how it evolved. They also contribute to there being a supercontinent because of the same fossils found overseas. The fossil record states: Older fossils are deeper in the ground and the younger on top.