Asked in GeologyPaleontologySpeleology
Precambrian Time which includes most of Earths history began with?
Asked in Paleontology
What major event in earths history began about 225 million years ago?
Asked in Geology
Differentiate preCambrian era and paleozoic era?
Asked in Geology, Paleontology, Earth Sciences
When was the Precambrian?
The Precambrian is the informal name for the large expanse of time preceding the current Phanerozoic Eon. It began with the Earth's formation about 4.5 billion years ago and lasted until the advent of multicellular life about 542 million years ago. Overall the planetary environment was drastically different. Life appeared sometime late in the Precambrian, but it is not known when. The Precambrian "supereon" is divided into three eons: the Hadean, Archaean, and Proterozoic. Very little is known about the Precambrian, despite the fact that it comprises nearly 90% of the Earth's history. This is simply because Precambrian rocks are so old, and are either heavily metamorphosed, have been destroyed by erosion, or remain buried deep beneath Phanerozoic strata.
Asked in Earth Sciences
What is the significance of the didvision between the Cambrian and PreCambrian periods?
Asked in Science, Geology, Animal Life
Which span of geologic time is the longest?
How long did the PreCambrian era last?
The Precambrian Era. The name means: "before the Cambrian period." This old, but still common term was originally used to refer to the whole period of earth's history before the formation of the oldest rocks with recognizable fossils in them. In the last few decades, however, geologists have found that there are some hard-to-discern fossils in some Precambrian rocks, so this period is now also known as the Cryptozoic or "obscure life" Eon (from the words "crypt" = "hidden," and "zoon" = "life"). The Precambrian covers almost 90% of the entire history of the Earth. It has been divided into three eras: the Hadean, the Archean and the Proterozoic. Source: Unknown The Precambrian Era comprises all of geologic time prior to 600 million years ago. The Precambrian was originally defined as the era that predated the emergence of life in the Cambrian Period. It is now known, however, that life on Earth began by the early Archean and that fossilized organisms became more and more abundant throughout Precambrian time. The two major subdivisions of the last part of the Precambrian are the Archean (oldest) and the Proterozoic. Rocks younger than 600 Ma are considered part of the Phanerozoic.
What made the precambrian start?
Asked in Geology
What is the oldest time period?
Asked in The Difference Between
What is the most significant difference between Precambrian and Paleozoic life-forms?
The Precambrian life forms were less developed than the Paleozoic life forms. The Precambrian life forms were just starting to develop because this was 544 million years ago. that meant that things still needed to grow. This time didn't last very long though, due to the morphic and erosional processes. The Paleozoic Era began when organisms began developing new hard parts. This made it easier for fossils to be preserved.
Asked in History of the United States, Imperialism
Do you think American History began as an offshoot of European imperialism?
Asked in Ancient Egypt
Did the third dynasty began the period in egypians history called the Old Kingdom?