New Hampshire Geology New Hampshire Bedrock Map

Precambrian Period page 3
(4600-540 million years ago)


Good Things Come In Small Packages

During the next 1.96 billion years, known as the Proterozoic Eon (42.6 yards long on the "100 Yard Model"),  several major milestones come to pass:

The Earth cools enough for the water vapor in the atmosphere to condense into liquid and solid forms. The oceans are formed.

The hydrologic (water) cycle begins.  This starts the weathering and erosion of landforms.  This is very important for wearing down mountain ranges and depositing layers of sediments that will form sedimentary rocks.

The first life forms develop in the primordial oceans. These would consist only of single celled organisms until the very end of the Precambrian Period when multicellular life appears.

 
Cellular Life


The first life forms on Earth were most likely single celled organisms.

Image credit:
Wilhelm Foissner, Institute of Zoology, University of Salzburg for the Bureau of Land Management, U.S. Dept. of the Interior


 

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