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The oldest dated rocks formed on Earth, as an aggregate of minerals that have not been subsequently broken down by erosion or melted, are more than 4 billion years old, formed during the Hadean Eon of Earth's geological history, and mark the start of the Archean Eon, which is defined to start with the formation of the oldest intact rocks on Earth.
The earliest evidence of life found in a stratigraphic unit, not just a single mineral grain, is the 3.7 Ga metasedimentary rocks containing graphite from the Isua Supracrustal Belt in Greenland. [3] The earliest direct known life on Earth are stromatolite fossils which have been found in 3.480-billion-year-old geyserite uncovered in the ...
Quartz-pebble metaconglomerate (Jack Hills Quartzite), the rock type that contains Earth's oldest dated mineral grains (detrital zircon) Detrital zircons with ages greater than 4 billion years old have been found in these rocks, and a 4,404 ± 8 million year old zircon was found at Erawandoo Hill; [4] this is the oldest dated material originating on Earth; the date is in the Cryptic era of the ...
Hadean zircon is the oldest-surviving crustal material from the Earth's earliest geological time period, the Hadean eon, about 4 billion years ago. Zircon is a mineral that is commonly used for radiometric dating because it is highly resistant to chemical changes and appears in the form of small crystals or grains in most igneous and metamorphic host rocks.
The oldest minerals on Earth are detrital zircon grains from the Yilgarn Craton in the Mesoarchaean (3.2–2.8 Ga) Jack Hills, Western Australia dated to up to 4.4 Ga, meaning that granitic continental crust and probably supracrustal rocks formed during the Hadean, within 200 million years of Earth accretion. Most Hadean rocks were probably ...
Analyzing the chemical composition of the meteorite’s 4.45 billion-year-old zircon grain — a mineral that is typically only a few millimeters in size and formed in rocks that have been altered ...
The oldest such minerals analyzed to date—small crystals of zircon from the Jack Hills of Western Australia—are at least 4.404 billion years old. [ 6 ] [ 9 ] [ 10 ] Calcium–aluminium-rich inclusions —the oldest known solid constituents within meteorites that are formed within the Solar System —are 4.567 billion years old, [ 11 ] [ 12 ...
c. 4,250 Ma – Earliest evidence for life, based on unusually high amounts of light isotopes of carbon, a common sign of life, found in Earth's oldest mineral deposits located in the Jack Hills of Western Australia. [4] c. 4,100 Ma – Early Imbrian Era begins on Earth.