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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. Early thermal weapons - Wikipedia

    en.wikipedia.org/wiki/Early_thermal_weapons

    The Siege and Destruction of Jerusalem by the Romans Under the Command of Titus, A.D. 70, by David Roberts (1850), shows the city burning. Early thermal weapons, which used heat or burning action to destroy or damage enemy personnel, fortifications or territories, were employed in warfare during the classical and medieval periods (approximately the 8th century BC until the mid-16th century AD).

  4. 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 ...

  5. Deep crustal hot zone - Wikipedia

    en.wikipedia.org/wiki/Deep_crustal_hot_zone

    The Deep Crustal Hot Zone (DCHZ), or just deep hot zone, is a zone in the lower crust where hot mantle material intrudes. [1] [2] In a volcanic arc setting, hot, molten material from the mantle may intrude into the lower crust. This hot material generates a new, more evolved melt in this area of the crust, which may collect and migrate upwards ...

  6. 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 ...

  7. Thermal history of Earth - Wikipedia

    en.wikipedia.org/wiki/Thermal_history_of_Earth

    In 1862, Lord Kelvin calculated the age of the Earth at between 20 million and 400 million years by assuming that Earth had formed as a completely molten object, and determined the amount of time it would take for the near-surface to cool to its present temperature. Since uniformitarianism required a much older Earth, there was a contradiction.

  8. Earth's outer core - Wikipedia

    en.wikipedia.org/wiki/Earth's_outer_core

    Earth's outer core is a fluid layer about 2,260 km (1,400 mi) thick, composed of mostly iron and nickel that lies above Earth's solid inner core and below its mantle. [ 1 ] [ 2 ] [ 3 ] The outer core begins approximately 2,889 km (1,795 mi) beneath Earth's surface is at the core-mantle boundary and ends 5,150 km (3,200 mi) beneath Earth's ...

  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).