Stromatolites of America

Fossil Galleries
 
American Stromatolites - Precambrian (Archaean and Proterozoic) Stromatolites
Page 1

Related pages:
Stromatolites
Large Stromatolite Images

 

 

Page 1: Precambrian (Archaean and Proterozoic) Stromatolites
Page 2: Phanerozoic Stromatolites

It is common to think of Australia when stromatolites are mentioned owing to the famous Shark Bay living stromatolites, as well as the bacterial microfossils and molecular fossils found in inland Australia that date to before 3 billion years ago. In fact, however, American North, South and Central) has numerous outcrops of stromatolites spanning across the continent as well as geological time. Older stromatolites are particularly abundant in the Northern states of Wisconsin, Michigan and Minnesota dating from about the upper Archaean to the Lower Proterozoic, including expansive banded iron formations that stand as testament to the rusting of the earth.

The American stromatolites image gallery below has specimens that have been cut and polished to a mirror finish. While rough stromatolites are generally dull and unremarkable in appearance, the fine polishing renders the inherent beauty of the oldest fossils on earth, including a myriad of colors and much variation in form genera and lamination structure.


Archaean Stromatolites
Hadrophycus immanus Stromatolites
Archaean (2.58 billion years old)
Libby Super Group, Nash Fork Shear Zone, Libby Flats Medicine Bow Range, Wyoming
Banded Iron Stromatolites
Archaean (2.87 billion years old)
Goldman Meadows Formation, Atlantic City Iron Mine, South Pass, Wyoming
Banded Iron Stromatolites
Archaean (2.73 billion years old)
Jackson County Iron Formation in Wisconsin
Stratifera form genera Stromatolites
Archaean (>2.58 billion years old)
Lower Whalen Group, Hartville Uplift, near Guernsey, Wyoming
Brecciated Banded Iron Stromatolites
Archaean (2.73 billion years old)
Jackson County Iron Formation in Wisconsin
Proterozoic Stromatolites Chocolay Group, Chocolay Hills, Northern Michigan
Proterozoic Stromatolites
Lower Proterozoic (2.2 to 2.4 billion years old)
Chocolay Group, Chocolay Hills, Northern Michigan
Lower Proterozoic (2.2 to 2.4 billion years old)
Chocolay Group, Chocolay Hills, Northern Michigan
Lower Proterozoic (2.2 to 2.4 billion years old)
Chocolay Group, Chocolay Hills, Northern Michigan
This specimen is interesting in that it exhibits both flat and wavy lamination outside the Girvanella form, and there are red blotches that are precipitated Rhodochrosite.
Gunflint Stomatolites (1.9 billion)
Gunflint Formation, Ontario, Canada

In the March 7, 2002 edition of Nature (Volume 406), J.W. Schopf, himself famous for his role in the discovery of Domain of Life Archaea, reported discovery of cellular remains of prokaryotic cells in the Gun Flint stromatolite. Note the intricate domal layers of this chertized (Chert is cryptocrystalized quartz) stromatolite that represents a piece of history in the study of Pre-Cambrian paleobiology.
Banded Iron (2.1 billion)
Upper Michigan
Newlandia concentrica (2.0 billion)
Greyson Shale, Big Belt Mountains, Montana
Walcott described and named this strange and unique (i.e., problematic) stromatolite in 1914
Collenia undosa (2.3 billion)
Biwabik Formation, Mary Ellen Mine, Mesabi Range, St. Louis County, Minnesota
Also called Mary Ellen Jasper, it is often used to make jewelry
From Alaska (age unknown), where it
occasionally washes ashore and is collected by the Inuit Native Americans.
Lower Proterozoic (2.4 billion)
Bad River Dolomite, Bayfield County, Wisconsin
Lower Proterozic (2.3 billion)
Eastern Andies South of Cochabamba, District of Cochabamba, Bolivia, South America

Stromatolites Images by Marlene Garo