Dresser Formation
The Dresser Formation is a Paleoarchean geologic formation that outcrops as a generally circular ring of hills the North Pole Dome area of the East Pilbara Terrane of the Pilbara Craton of Western Australia. This formation is one of many formations that comprise the Warrawoona Group, which is the lowermost of four groups that comprise the Pilbara Supergroup. The Dresser Formation is part of the Panorama greenstone belt that surrounds and outcrops around the intrusive North Pole Monzogranite. Dresser Formation consists of metamorphosed, blue, black, and white bedded chert; pillow basalt; carbonate rocks; minor felsic volcaniclastic sandstone and conglomerate; hydrothermal barite; evaporites; and stromatolites. The lowermost of three stratigraphic units that comprise the Dresser Formation contains some of the Earth's earliest commonly accepted evidence of life such as morphologically diverse stromatolites, microbially induced sedimentary structures, putative organic microfossils, and biologically fractionated carbon and sulfur isotopic data.
Dresser Formation | |
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Stratigraphic range: Paleoarchaen | |
Type | Geological formation |
Unit of | Warrawoona Group |
Sub-units | two bedded chert horizons separated by pillow basalt |
Underlies | Mount Ada Basalt |
Overlies | North Star Basalt |
Area | limited to Panorama greenstone belt surrounding North Pole Dome of Pilbara Craton |
Lithology | |
Primary | bedded chert, volcaniclastic sandstone, felsic tuff, conglomerate, breccia, and jaspilitic chert |
Other | basalt |
Location | |
Coordinates | 21.151759°S 119.437252°E |
Region | Western Australia |
Country | Australia |
Extent | 25 km2 (9.7 sq mi) |
Type section | |
Named for | Dresser Mine |
Named by | M. J. Van Kranendonk |
Location | Dresser Mine |
Year defined | 2000 |
Region | Western Australia |
Country | Australia |