General
During the Proterozoic Period, the Earth’s crust expanded greatly and the transition to an oxygenated atmosphere allowing for the emergence of single-celled and multi-cellular life.
Tectonics and Paleoclimate
During the Proterozoic eon, the first continents began to develop and to expand into the supercontinent of Rodinia. For the first time, the Earth experiences a notable build up of oxygen in the atmosphere. The Earth was covered with extensive shallow salt water seas. Some rocks from the Proterozic Eon have survived into present day relatively unaltered and indicate that this eon featured massive, rapid continental expansion, aggregation and dispersal of Earth's continental crust (e.g., supercontinent cycles), and natural mountain building. The first known glaciations occurred during the Proterozoic, one began shortly after the beginning of the eon and several at the end of the eon leading into the global Sturtian glaciation.
Flora
Plant life during the Proterozoic eon was mostly limited to red and green algae and other multi-cellular flora such as that which left behind “carbon films” (small, dark compressions, most resembling circles, ribbons, leaves or seaweed). There were no known land plants.
Fauna
The fauna during the Proterozoic starts out with the first advanced single-celled and multi-cellular life including soft-bodied organisms such as bacteria, archaeans, eukaryotes , and Stromatolites (layered mounds produced by the growth of microbial mats) which continued to diversity and expand throughout most of the eon. It is theorized that during the Proterozoic the first symbiotic relationships between mitochondria (fauna) and chloroplasts (flora) and their respective hosts evolved.
Meteorite Impacts on Earth
I included a list of meteorite impacts relevant to this time period as a point of reference since many of the explanations for mass extinctions throughout Earth’s history include meteorite impact(s) as a possible cause. The meteorite impact information below was obtained from the ‘Earth Impact Database’ maintained by the Planetary and Space Science Centre, University of New Brunswick, Fredericton, New Brunswick, Canada ( www.passc.net/EarthImpactDatabase). |
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Crater Name | Country & Continent | Diameter | Longitude | Latitude | M.Y.A. |
Foelsche | Australia, Oceania | 6.00 km (3.728 mi) | E 136° 47' | S 16° 40' | 545 |
Holleford | Canada, North America | 2.35 km (1.460 mi) | W 76° 38' | N 44° 28' | 550 |
Kelly West | Australia, Oceania | 10.00 km (6.214 mi) | E 133° 57' | S 19° 56' | 550 |
Sääksjärvi | Finland, Europe | 6.00 km (3.728 mi) | E 22° 24' | N 61° 24' | 560 |
Spider | Australia, Oceania | 13.00 km (8.078 mi) | E 126° 5' | S 16° 44' | 570 |
Acraman | Australia, Oceania | 90.00 km (55.923 mi) | E 135° 27' | S 32° 1' | 590 |
Söderfjärden | Finland, Europe | 6.60 km (4.101 mi) | E 21° 35' | N 63° 2' | 600 |
Saarijärvi | Finland, Europe | 1.50 km (.932 mi) | E 28° 23' | N 65° 17' | 600 |
Beaverhead | United States, North America | 60.00 km (37.282 mi) | W 113° 0' | N 44° 36' | 600 |
Strangways | Australia, Oceania | 25.00 km (15.534 mi) | E 133° 35' | S 15° 12' | 646 |
Jänisjärvi | Russian Federation, Asia | 14.00 km (8.699 mi) | E 30° 55' | N 61° 58' | 700 |
Lumparn | Finland, Europe | 9.00 km (5.592 mi) | E 20° 6' | N 60° 9' | 1,000 |
Suvasvesi N | Finland, Europe | 4.00 km (2.485 mi) | E 28° 10' | N 62° 42' | 1,000 |
Iso-Naakkima | Finland, Europe | 3.00 km (1.864 mi) | E 27° 9' | N 62° 11' | 1,000 |
Goyder | Australia, Oceania | 3.00 km (1.864 mi) | E 135° 2' | S 13° 28' | 1,400 |
Shoemaker (formerly Teague) | Australia, Oceania | 30.00 km (18.641 mi) | E 120° 53' | S 25° 52' | 1,630 |
Amelia Creek | Australia, Oceania | 20.00 km (12.427 mi) | E 134 ° 50' | S 20° 55' | 1,640 |
Keurusselkä | Finland, Europe | 30.00 km (18.641 mi) | E 24° 36' | N 62° 8' | 1,800 |
Paasselkä | Finland, Europe | 10.00 km (6.214 mi) | E 29° 5' | N 62° 2' | 1,800 |
Sudbury | Canada, North America | 250.00 km (155.343 mi) | W 81° 11' | N 46° 36' | 1,850 |
Yarrabubba | Australia, Oceania | 30.00 km (18.641 mi) | E 118° 50' | S 27° 10' | 2,000 |
Vredefort | South Africa, Africa | 300.00 km (186.411 mi) | E 27° 30' | S 27° 0' | 2,023 |
Suavjärvi | Russian Federation, Asia | 16.00 km (9.942 mi) | E 33° 23' | N 63° 7' | 2,400 |
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