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  2. Marine biogeochemical cycles - Wikipedia

    en.wikipedia.org/wiki/Marine_biogeochemical_cycles

    Phosphorus occurs most abundantly in nature as part of the orthophosphate ion (PO 4) 3−, consisting of a P atom and 4 oxygen atoms. On land most phosphorus is found in rocks and minerals. Phosphorus-rich deposits have generally formed in the ocean or from guano, and over time, geologic processes bring ocean sediments to land.

  3. Biogeochemical cycle - Wikipedia

    en.wikipedia.org/wiki/Biogeochemical_cycle

    Geologic processes, such as weathering, erosion, water drainage, and the subduction of the continental plates, all play a role in this recycling of materials. Because geology and chemistry have major roles in the study of this process, the recycling of inorganic matter between living organisms and their environment is called a biogeochemical cycle.

  4. Geochemical cycle - Wikipedia

    en.wikipedia.org/wiki/Geochemical_cycle

    Some [who?] may use the terms biogeochemical cycle and geochemical cycle interchangeably because both cycles deal with Earth's reservoirs.However, a biogeochemical cycle refers to the chemical interactions in surface reservoirs such as the atmosphere, hydrosphere, lithosphere, and biosphere [citation needed] whereas a geochemical cycle refers to the chemical interactions that exist in crustal ...

  5. Deep water cycle - Wikipedia

    en.wikipedia.org/wiki/Deep_water_cycle

    Estimates of the amount of water in the mantle range from 1 ⁄ 4 to 4 times the water in the ocean. [12] There are 1.37×10 18 m 3 of water in the seas, therefore, this would suggest that there is between 3.4×10 17 and 5.5×10 18 m 3 of water in the mantle. Constraints on water in the mantle come from mantle mineralogy, samples of rock from ...

  6. History of geology - Wikipedia

    en.wikipedia.org/wiki/History_of_geology

    [2] [3] [4] Some of the first geological thoughts were about the origin of the Earth. Ancient Greece developed some primary geological concepts concerning the origin of the Earth. Additionally, in the 4th century BC Aristotle made critical observations of the slow rate of geological change. He observed the composition of the land and formulated ...

  7. Geodynamics - Wikipedia

    en.wikipedia.org/wiki/Geodynamics

    Geodynamics is a broad field which combines observations from many different types of geological study into a broad picture of the dynamics of Earth. Close to the surface of the Earth, data includes field observations, geodesy, radiometric dating , petrology , mineralogy, drilling boreholes and remote sensing techniques.

  8. Magmatism - Wikipedia

    en.wikipedia.org/wiki/Magmatism

    Geological map showing the Gangdese batholith, which is a product of magmatic activity about 100 million years ago Not to be confused with Magnetism . Magmatism is the emplacement of magma within and at the surface of the outer layers of a terrestrial planet , which solidifies as igneous rocks .

  9. Geobiology - Wikipedia

    en.wikipedia.org/wiki/Geobiology

    The geologic timescale overlain with major geobiologic events and occurrences. The oxygenation of the atmosphere is shown in blue starting 2.4 Ga, although the exact dating of the Great Oxygenation Event is debated. [14] Perhaps the most profound geobiological event is the introduction of oxygen into the atmosphere by photosynthetic bacteria.