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  2. Rock (geology) - Wikipedia

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

    Metamorphic rocks are formed by subjecting any rock type—sedimentary rock, igneous rock or another older metamorphic rock—to different temperature and pressure conditions than those in which the original rock was formed. This process is called metamorphism, meaning to "change in form". The result is a profound change in physical properties ...

  3. Rubidium–strontium dating - Wikipedia

    en.wikipedia.org/wiki/Rubidium–strontium_dating

    The rubidium–strontium dating method (Rb–Sr) is a radiometric dating technique, used by scientists to determine the age of rocks and minerals from their content of specific isotopes of rubidium (87 Rb) and strontium (87 Sr, 86 Sr). One of the two naturally occurring isotopes of rubidium, 87 Rb, decays to 87 Sr with a half-life of 49.

  4. Crust (geology) - Wikipedia

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

    The internal structure of Earth. In geology, the crust is the outermost solid shell of a planet, dwarf planet, or natural satellite.It is usually distinguished from the underlying mantle by its chemical makeup; however, in the case of icy satellites, it may be defined based on its phase (solid crust vs. liquid mantle).

  5. Earth's internal heat budget - Wikipedia

    en.wikipedia.org/wiki/Earth's_internal_heat_budget

    Thus, about 99% of Earth's internal heat loss at the surface is by conduction through the crust, and mantle convection is the dominant control on heat transport from deep within the Earth. Most of the heat flow from the thicker continental crust is attributed to internal radiogenic sources; in contrast the thinner oceanic crust has only 2% ...

  6. Porosity - Wikipedia

    en.wikipedia.org/wiki/Porosity

    In fractured rock aquifers, the rock mass and fractures are often simulated as being two overlapping but distinct bodies. Delayed yield, and leaky aquifer flow solutions are both mathematically similar solutions to that obtained for dual porosity; in all three cases water comes from two mathematically different reservoirs (whether or not they ...

  7. Hydrogeology - Wikipedia

    en.wikipedia.org/wiki/Hydrogeology

    Fault zone hydrogeology is the study of how brittlely deformed rocks alter fluid flows in different lithological settings, such as clastic, igneous and carbonate rocks. Fluid movements, that can be quantified as permeability, can be facilitated or impeded due to the existence of a fault zone. [7] This is because different mechanism and deformed ...

  8. Our DNA is 99.9 percent the same as the person sitting next ...

    www.aol.com/article/2016/05/06/our-dna-is-99-9...

    For humans, we're 99.9 percent similar to the person sitting next to us. The rest of those genes tell us everything from our eye color to if we're predisposed to certain diseases.

  9. Volcanic gas - Wikipedia

    en.wikipedia.org/wiki/Volcanic_gas

    Molten rock (either magma or lava) near the atmosphere releases high-temperature volcanic gas (>400 °C). In explosive volcanic eruptions, the sudden release of gases from magma may cause rapid movements of the molten rock. When the magma encounters water, seawater, lake water or groundwater, it can be rapidly fragmented.