Answer:
The geologist time scale was formed when scientists studied rock layers and index fossils worldwide. With this information, they placed Earth's rocks in order by relative age. Later, radioactive dating helped determine the exact age of the divisons in the geologic time scale.
This scale is organized by the 4.6 billion years of earth's history into sections based on important changes seen in the geologic record. The largest intervals are called eons, with each eon containing many millions of years.
In precambarian time the processes that affect Earth's surface have lessened the erosion on the surface. Earth was being hit by meteorites every second. Now there is water erosion and there wasn't back then. The surface changes have lessened over time.
Answer: (written in paragraph form)
Scientists formed the geologic time scale by looking and studying layers of rock as well as index layers from around the world. Then they decided the rocks order from the estimated date of age. The geologic scale is organized in to parts based off of important things/changes in the geologic record. This parts can be identified by the names Eras, Eons, Periods, or Ages. Eons are the biggest, having millions of years with in them. Finally, in the precambrian time, processes/results of these processes include differing climate conditions, less water erosions, and lastly photosynthesis changed the Earth's environment.
Hope this helps! >-<
