Jack Hills

mountains, Australia

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June 29, 2026

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The Jack Hills are not mountains but a geological formation in Western Australia known for containing the oldest known minerals on Earth: detrital zircons that crystallized approximately 4.4 billion years ago. These ancient zircons are found within younger sedimentary rocks, and the original rocks from which they formed are unknown, possibly destroyed by tectonic activity or meteorite impacts. The Hadean Eon, which spans from Earth's formation about 4.6 billion years ago to 4.0 billion years ago, is characterized by the planet's initial formation, the stabilization of its core and crust, and the development of its atmosphere and oceans. During this time, Earth's surface was highly unstable due to frequent impacts and intense heat.12

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Precambrian
Age and correlation of granulite-gneiss belts
…zircons at Mount Narryer and Jack Hills in Western Australia that are more than 4 billion years old. Several regions have a history that began in the period dating from 3.9 to 3.6 billion years ago—western Greenland, Labrador, the Limpopo belt, Enderby Land, the North China craton, and the Aldan…
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…zircons at Mount Narryer and Jack Hills in Western Australia that are more than 4 billion years old. Several regions have a history that began in the period dating from 3.9 to 3.6 billion years ago—western Greenland, Labrador, the Limpopo belt, Enderby Land, the North China craton, and the Aldan…
Read More