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  2. Oldest dated rocks - Wikipedia

    en.wikipedia.org/wiki/Oldest_dated_rocks

    The Moon rock "Big Bertha", collected on the 1971 Apollo 14 mission, contains an Earth meteorite that is 4 billion years old. 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 ...

  3. Metamorphic rock - Wikipedia

    en.wikipedia.org/wiki/Metamorphic_rock

    The study of metamorphic rocks (now exposed at the Earth's surface following erosion and uplift) provides information about the temperatures and pressures that occur at great depths within the Earth's crust. Some examples of metamorphic rocks are gneiss, slate, marble, schist, and quartzite.

  4. Earliest known life forms - Wikipedia

    en.wikipedia.org/wiki/Earliest_known_life_forms

    The earliest known life forms on Earth may be as old as ... in 3.4 Ga rocks, including 3.465-billion-year-old Apex chert ... record due to metamorphic processes that ...

  5. Shield (geology) - Wikipedia

    en.wikipedia.org/wiki/Shield_(Geology)

    A shield is a large area of exposed Precambrian crystalline igneous and high-grade metamorphic rocks that form tectonically stable areas. [1] These rocks are older than 570 million years and sometimes date back to around 2 to 3.5 billion years.

  6. Nuvvuagittuq Greenstone Belt - Wikipedia

    en.wikipedia.org/wiki/Nuvvuagittuq_Greenstone_Belt

    These rocks have undergone extensive metamorphism, and represent some of the oldest surface rocks on Earth. Two papers dating the age of the Nuvvuagittuq Greenstone Belt have been published. One paper gave an age of c. 3,750 million years , [2] while the other gave an age of c. 4,388 Ma. [3]

  7. Gneiss - Wikipedia

    en.wikipedia.org/wiki/Gneiss

    Gneiss (/ n aɪ s / nice) is a common and widely distributed type of metamorphic rock. It is formed by high-temperature and high-pressure metamorphic processes acting on formations composed of igneous or sedimentary rocks. This rock is formed under pressures ranging from 2 to 15 kbar, sometimes even more, and temperatures over 300 °C (572 °F).

  8. Rock (geology) - Wikipedia

    en.wikipedia.org/wiki/Rock_(geology)

    It may be limited to rocks found on Earth, or it may include planetary geology that studies the rocks of other celestial objects. Rocks are usually grouped into three main groups: igneous rocks, sedimentary rocks and metamorphic rocks. Igneous rocks are formed when magma cools in the Earth's crust, or lava cools on the ground surface or the seabed.

  9. History of geology - Wikipedia

    en.wikipedia.org/wiki/History_of_geology

    Metamorphic) Sediment; ... had occurred and that the flood had formed the rock strata of the Earth. ... oldest Archean rocks to be 1,600 million years old, ...