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  2. Tar - Wikipedia

    en.wikipedia.org/wiki/Tar

    One can produce a tar-like substance from corn stalks by heating them in a microwave oven. This process is known as pyrolysis. Tar is a dark brown or black viscous liquid of hydrocarbons and free carbon, obtained from a wide variety of organic materials through destructive distillation. Tar can be produced from coal, wood, petroleum, or peat. [1]

  3. Geothermal gradient - Wikipedia

    en.wikipedia.org/wiki/Geothermal_gradient

    Earth cutaway from core to exosphere Geothermal drill machine in Wisconsin, USA. Temperature within Earth increases with depth. Highly viscous or partially molten rock at temperatures between 650 and 1,200 °C (1,200 and 2,200 °F) are found at the margins of tectonic plates, increasing the geothermal gradient in the vicinity, but only the outer core is postulated to exist in a molten or fluid ...

  4. Hotspot (geology) - Wikipedia

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

    It was later postulated that hotspots are fed by streams of hot mantle rising from the Earth's core–mantle boundary in a structure called a mantle plume. [6] Whether or not such mantle plumes exist has been the subject of a major controversy in Earth science, [ 4 ] [ 7 ] but seismic images consistent with evolving theory now exist.

  5. Earth's inner core - Wikipedia

    en.wikipedia.org/wiki/Earth's_inner_core

    Earth was discovered to have a solid inner core distinct from its molten Earth's outer core in 1936, by the Danish seismologist Inge Lehmann's [7] [8] study of seismograms from earthquakes in New Zealand, detected by sensitive seismographs on the Earth's surface. She deduced that the seismic waves reflect off the boundary of the inner core and ...

  6. Glossary of geology - Wikipedia

    en.wikipedia.org/wiki/Glossary_of_geology

    The name "illite" is inherited from the state of Illinois where natural non-swelling clay deposits exist. indurated Made hard (by heat or compaction). interbedded beds (layers) of rock lying between or alternating with beds of a different kind of rock. intrusion body of igneous rock that has crystallized from molten magma below the surface of ...

  7. Earth's internal heat budget - Wikipedia

    en.wikipedia.org/wiki/Earth's_internal_heat_budget

    Earth's tectonic evolution over time from a molten state at 4.5 Ga, [11] to a single-plate lithosphere, [24] to modern plate tectonics sometime between 3.2 Ga [25] and 1.0 Ga [26] Primordial heat energy comes from the potential energy released by collapsing a large amount of matter into a gravity well, and the kinetic energy of accreted matter.

  8. Earth's mantle - Wikipedia

    en.wikipedia.org/wiki/Earth's_mantle

    Earth's mantle is a layer of silicate rock between the crust and the outer core. It has a mass of 4.01 × 10 24 kg (8.84 × 10 24 lb) and makes up 67% of the mass of Earth. [ 1 ] It has a thickness of 2,900 kilometers (1,800 mi) [ 1 ] making up about 46% of Earth's radius and 84% of Earth's volume.

  9. Lava - Wikipedia

    en.wikipedia.org/wiki/Lava

    Lava is molten or partially molten rock that has been expelled from the interior of a terrestrial planet (such as Earth) or a moon onto its surface. Lava may be erupted at a volcano or through a fracture in the crust , on land or underwater, usually at temperatures from 800 to 1,200 °C (1,470 to 2,190 °F).