Definitions for "Precambrian"
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Quaternary, Miocene, Devonian period, Proterozoic, Pliocene, Tertiary, Archean, Archaean, Cenozoic era, Phanerozoic, Cretaceous, Paleocene, Neogene, Pleistocene, Phanerozoic eon, Eon, Cenozoic, Quaternary period, Triassic, Jurassic, Geologic time, Hadean, Eocene , Permian, Era, Cambrian period, Oligocene, Paleozoic era, Cambrian, Holocene, Carboniferous period, Permian period, Silurian, Devonian, Jurassic period, Paleozoic, Mesozoic era, Pennsylvanian, Cretaceous period, Mississippian, Carboniferous, Ordovician, Mesozoic, Triassic period, Palaeozoic, Recent, Pleistocene epoch, Holocene epoch, Cambrian explosion, Palaeolithic
All of geologic time before the Phanerozoic eon, i.e. about 90
The geological time period extending from formation of the earth to 600 million years before the present.
4,560-570 million years ago.
All geologic time before the beginning of the Paleozoic. It is equivalent to about 90% of geologic time (…4600-590 million years ago).
the most ancient period of geologic time that started at the Earth formation (4.6 billion years ago) and ended 570 million years ago.
The interval of geologic time between Earth's formation about 4.57 Ga and the beginning of the Phanerozoic Eon 542 Ma.
A time period in the earth's geologic history. This period began from the origin of earth to approx. 0.6 billion years ago. (See : GEOLOGIC TIME)
geologic era between the time when Earth's crust formed about 4.5 billion years ago to about 1 billion years ago.
All geologic time from the beginning of Earth history to 570 million years ago. Also refers to the rocks that formed in that epoch.
The period of time between the consolidation of the earth's crust and the beginning of the Cambrian period; about 4 billion years in duration.
This is the first and by far the longest geological period in Earth's history. It encompasses the time since the creation of the planet itself up to the start of the Cambrian period about 570 millions years ago; this makes the Precambrian approximately 4.5 billion years long! With recent discoveries in geology - in particular the discovery of very early life forms within Precambrian rocks - the term is now falling out of academic usage, although is still used as a general term. One of the features of the Precambrian was the lack of any evidence for life in rocks from that are; this is now known not to be the case.
A period of geological time, dating from the consolidation of the Earth's crust around 4600 million years ago to about 550 million years ago.
All geologic time, and its corresponding rocks, before the beginning of the Paleozoic; it is equivalent to about 90% of geologic time. Precambrian time has been divided according to several different systems, all of which use the presence or absence of evidence of life as a criterion.
That time span previous to the Paleozoic that comprises approximately 90% of earth history. (4.6 billion to 590 million years ago)
The first of the four Geologic Eras in which geologic time is divided. It extends from the beginning of Earth history (over 4 billion years ago) to the beginning of the Paleozoic Era (about 570 million years ago).
The division of geologic time from the formation of Earth (about 4.5 billion years ago) to the beginning of the Cambrian Period of the Paleozoic Era (about 600 million years ago). Also, the rocks formed during that time. Precambrian time constitutes about 90% of Earth's history.
the eon following the Hadean time and preceding the Phanerozoic eon; from about 3,800 million years ago until 544 million years ago
All geologic time from the formation of the earth, about 4.6 billion years ago, to the beginning of the Paleozoic Era, about 570 million years ago.
Rocks older than 600 million years. Earliest division of time for which rock strata are recognised.
adjective describing time before the Cambrian Era which was the time in Earth history when the first macroscopic life was found in the fossil record (in England when historical geology was first developing). The Precambrian-Cambrian boundary has recently been shifted in absolute time by Sam Bowring, John Grotzinger, and Beverly Saylor at MIT. It is now placed at about 540 million years ago. Thus, Precambrian time covers all rocks older than 540 million years old, including Hadean, Archean, and Proterozoic time.
All rocks formed, deposited and/or altered before the deposition of the Paleozoic rocks. Geologists assign a timeframe of 4500 million years to 570 Mya to these rocks. The Archean eon supposedly lasted from 4500 m.y. to 2500 m.y. with the Proterozoic eon comprising the remaining Precambrian time, 2500 m.y. to 570 m.y.b.p.
It is the extensive period of geological time which is literally used as "before the Cambrian." It contains around 90% of all geological time and it ends approximately 545 million years ago.
All geologic time before the beginning of the Paleozoic era. This includes about 90% of all geologic time and spans the time from the beginning of the earth, about 4.5 billion years ago, to 544 million years ago. Its name means "before Cambrian."
The 'unofficial' time period that encompasses all time from the Earth's formation, 4.55 billion years ago to 570 million years ago, the beginning of the Paleozoic Era. more details...
Informal term describing 7/8 of geologic time from the beginning of the earth to the beginning of the Cambrian Period of the Paleozoic Era. During this time the atmosphere and oceans formed, life originated (or possibly "colonized" Earth), eukaryotes and simple animals evolved and by the end of the precambrian they began to accumulate hard preservable parts, the common occurrence of which marks the beginning of the Cambrian. PICTURE
(see Geological Timescale)
The time-frame of the Precambrian period is 4.5 billion years to approximately 545 million years ago (when the Cambrian period begins). The Precambrian is divided into 3 eras, characterized as follows: Hadean (4.5 – 3.9 billion years ago): From the formation of the Earth until the first appearance of sedimentary rocks, with no record of fossil organisms. Archaen (3.9 – 2.5 billion years ago): Appearance of sedimentary rocks, stromatalites, and benthic prokaryotes. Proterozoic (2.5 -0.545 billion years ago): Appearance of planktonic prokaryotes, followed by appearance of eukaryotic cells, followed by appearance of multicellular organisms.
The period in Earth's history from its formation to 600 million years ago.
all time prior to 570 million years ago.
The earliest part of the geological time scale, including all corresponding rocks, equivalent to about 90 percent of geologic time; from the beginning of time until the beginning of the Paleozoic, about 600 million years ago.
the earliest geological period, from the formation of the Earth to about 590 million years ago, when the first single-celled and primitive multi-celled organisms appeared
All geologic time before 570 million years ago
geologic era ranging from 3400 Ma to 540 Ma. Comprise Archean from 3400 Ma to 2500 Ma and Proterozoic from 2500 Ma to 540 Ma.
The time before 600 million years ago
The part of the geological record that exists before 570 Ma. As the Earth is about 4.6 BILLION years old it is a very long period of time
A geological term denoting the time in Earth history prior to 570 million years ago.
Span of geologic time that dates from 4.6 billion to 570 million years ago. Made up of three geologic eras: Hadean, Archean, and Proterozoic.
The period of time from the formation of the Earth (4500Ma) to about 590Ma;
The period of time stretching from the formation of Earth 4.6 billion years ago to the beginning of the Paleozoic period, 545 million years ago.
the geologic time period between 4.6 billion years ago and 544 million years ago
the earliest era in geological time, emcompassing all the time before the Cambrian period; rocks formed in the Precambrian. [AHDOS
The Precambrian is the time 540 before the Cambrian period (before million years ago). It is the time from when the Earth formed until simple life-forms evolved.
Of or belonging to the period of geological time from approx. 3.8 billion years ago to approx. 570 million years ago, often subdivided into the Archean and Proterozoic eons.
The ancient epoch of geological time (3.5 billion to 600 million years ago), marked in the North Country by the Early Precambrian Keewatin, Laurentian, Knife Lake, and Algoman periods (3.5 to 2.7 billion years ago); the Middle Precambrian Early, Middle, and Late Huronian( Animikean) periods (2.6 to 1.6 billion years ago); and the Late Precambrian Early, Middle, and Late Keweenawan periods (1.6 billion to 600 million years ago).
The Precambrian (or Pre-Cambrian) is an informal name for the eons of the geologic timescale that came before the current Phanerozoic eon. It spans from the formation of Earth around 4500 Ma (million years ago) to the evolution of abundant macroscopic hard-shelled fossils, which marked the beginning of the Cambrian, the first period of the first era of the Phanerozoic eon, some 542 Ma.
Primary recovery