Just a chronometrically perfect second – I am still in Switzerland, right?
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All of these units except for the Ediacaran are defined chronometrically.
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The second half opened in chronometrically identical fashion, but even more expensively for the Broncos.
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The new fossils are from chronometrically controlled stratigraphic sequences and date to about 4.1-4.2 million years ago.
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The base of the Mesoproterozoic is defined chronometrically, in terms of years, rather than by the appearance or disappearance of some organism.
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This numismatic and thus chronometrically valid distinction, however, could be useful regardless of whether the two brothers used the same or different passes.
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With them, the ancients could accurately measure the size of the earth, map it, and chronometrically tick off the cyclic passage of the ages.
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135(6), 1367-1370.Zelmanov A. L. and Khabibov Z. R. Chronometrically invariant variations in Einstein's gravitation theory. Doklady Akademii Nauk SSSR, 1982, v.268(6), 1378-1381.).
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Ryan Harris, the mechanical man of Australian bowling, a bowler so chronometrically accurate that he might have been made by watchmakers in Switzerland, sent down a half-volley.
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The Neoarchean (; also spelled Neoarchaean) is a geologic era within the Archaean Eon. The Neoarchean spans the period from --the period being defined chronometrically and not referenced to a specific level in a rock section on Earth.
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The Mesoarchean (, also spelled Mesoarchaean) is a geologic era within the Archean Eon, spanning . The era is defined chronometrically and is not referenced to a specific level in a rock section on Earth. Fossils from Australia show that stromatolites have grown on Earth since the Mesoarchean. The Pongola glaciation occurred around .
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The Statherian Period (; , meaning "stable, firm") is the final geologic period in the Paleoproterozoic Era and lasted from Mya to Mya (million years ago). Instead of being based on stratigraphy, these dates are defined chronometrically. The period was characterized on most continents by either new platforms or final cratonization of fold belts. Oxygen levels were 10% to 20% of current values.
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The Stenian Period (from Greek στενός (stenós), meaning "narrow") is the final geologic period in the Mesoproterozoic Era and lasted from Mya to Mya (million years ago). Instead of being based on stratigraphy, these dates are defined chronometrically. The name derives from narrow polymetamorphic belts formed over this period. Preceded by the Ectasian period and followed by the Neoproterozoic Era.
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The word 'Archean' comes from the ancient Greek word ('), meaning 'beginning, origin.' It was first used in 1872, when it meant "of the earliest geological age." Before the Hadean Eon was recognized, the Archean spanned Earth's early history from its formation about 4,540 million years ago (Mya) until 2,500 Mya. Instead of being based on stratigraphy, the beginning and end of the Archean Eon are defined chronometrically.
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The Rhyacian Period (; , meaning "stream of lava") is the second geologic period in the Paleoproterozoic Era and lasted from Mya to Mya (million years ago). Instead of being based on stratigraphy, these dates are defined chronometrically. The Bushveld Igneous Complex and other similar intrusions formed during this period. The Huronian (Makganyene) global glaciation began at the start of the Rhyacian and lasted 100 million years.
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The Ectasian Period (from Greek ἔκτασις (éktasis), meaning "extension") is the second geologic period in the Mesoproterozoic Era and lasted from Mya ago to Mya (million years ago). Instead of being based on stratigraphy, these dates are defined chronometrically. Geologically the name refers to the continued expansion of platform covers during this period. This period is interesting for the first evidence of sexual reproduction.
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The Calymmian Period (from Greek κάλυμμα (kálymma), meaning "cover") is the first geologic period in the Mesoproterozoic Era and lasted from Mya to Mya (million years ago). Instead of being based on stratigraphy, these dates are defined chronometrically. The period is characterised by expansion of existing platform covers, or by new platforms on recently cratonized basements. The supercontinent Columbia started to break during the Calymmian some 1500 Mya.
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The Orosirian Period (; , meaning "mountain range") is the third geologic period in the Paleoproterozoic Era and lasted from Mya to Mya (million years ago). Instead of being based on stratigraphy, these dates are defined chronometrically. Vredefort crater is believed to have formed in this period The later half of the period was an episode of intensive orogeny on virtually all continents. Two of the largest known impact events on Earth occurred during the Orosirian.
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The Siderian Period (; , meaning "iron") is the first geologic period in the Paleoproterozoic Era and lasted from Ma to Ma (million years ago). Instead of being based on stratigraphy, these dates are defined chronometrically. A Siderian banded iron formation in Dales Gorge, Western Australia The deposition of banded iron formations peaked early in this period. These iron rich formations were formed as anaerobic cyanobacteria produced waste oxygen that combined with iron, forming magnetite (Fe3O4, an iron oxide).
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The golden spikes on geologic timescales represent internationally agreed upon references for the boundaries of the stages in the geologic timescale. These contacts have been identified by the International Commission on Stratigraphy and they are known as GSSPs, or global boundary stratotype section and points. Some of these boundary points are at physical locations, while others are in ice drill core sections, or have been defined chronometrically. The GSSP for the Danian Stage marks the end of the Cretaceous and the beginning of the Paleocene Series.
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The ancient implements belonged to the Somaliland Stillbay culture typified by points and scrapers produced through flat percussion flaking. J.D. Clark a decade later excavated a nearby site, the Gury Waabay ("the poisonous house"), located around half a kilometer to the north. In the 1980s, Brandt also excavated the granitic inselberg, uncovering a top level Holocene layer. Fourteen burials were found therein, which constitute the earliest chronometrically dated burials from the Horn of Africa and contain the earliest definitive grave artefacts in the wider region.
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A stromatolite formed by Paleoarchean miocrobial mats, preserved as a fossil, from Pilbara craton, Western Australia The Paleoarchean (), also spelled Palaeoarchaean (formerly known as early Archean), is a geologic era within the Archaean eon. It spans the period of time --the era is defined chronometrically and is not referenced to a specific level of a rock section on Earth. The name derives from Greek "Palaios" ancient. The oldest ascertained life form of fossilized bacteria in microbial mats, old, found in the Dresser Formation in Western Australia, is from this era.
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