huronian — hyüˈrōnēən adjective Usage: usually capitalized Etymology: Lake Huron (north of which the system was first differentiated) : of or relating to a division of the Proterozoic see geologic time table … Useful english dictionary
Keweenawan System — ▪ geochronology division of late Precambrian rocks and time in North America (the Precambrian began about 3.8 billion years ago and ended 540 million years ago). Rocks of the Keweenawan System are about 10,700 metres (about 35,000 feet)… … Universalium
Bruce Series — ▪ geology division of Precambrian rocks in North America that is well developed northeast of the Lake Huron region (the Precambrian began about 3.8 billion years ago and ended 540 million years ago). The Bruce Series is the lowermost of the … Universalium
Animikie Series — ▪ geology division of Precambrian rocks and time in North America (the Precambrian occurred from 3.96 billion to 540 million years ago). The Animikie Series, the uppermost division of the Huronian System, overlies rocks of the Cobalt Series … Universalium
Michigan — This article is about the U.S. state of Michigan. For other uses, see Michigan (disambiguation). State of Michigan … Wikipedia
Thomas Sterry Hunt — (* 5. September 1826 in Norwich (Connecticut); † 12. Februar 1892 in New York City) war ein US amerikanischer Chemiker und Mineraloge. [1] … Deutsch Wikipedia
Precambrian time — Interval of geologic time from с 3. 8 billion years ago, the age of the oldest known rocks, to 544 million years ago, the beginning of the Cambrian Period. This interval represents more than 80% of the geologic record and thus provides important… … Universalium
Great Oxygenation Event — O2 build up in the Earth s atmosphere. Red and green lines represent the range of the estimates while time is measured in billions of years ago (Ga). Stage 1 (3.85–2.45 Ga): Practically no O2 in the atmosphere. Stage 2 (2.45–1.85 Ga): O2 produced … Wikipedia
Timetable of the Precambrian — This is a timeline of geological and relevant astronomical events on Earth before the Cambrian period started. This covers 88% of the duration of the Earth. The dates given are based on the best current scientific evidence and where possible are… … Wikipedia
Snowball Earth — The Snowball Earth hypothesis as it was originally proposedcite book author = Kirschvink, J.L. year = 1992 chapter = Late Proterozoic low latitude global glaciation: The snowball Earth title = The Proterozoic Biosphere: A Multidisciplinary Study… … Wikipedia
