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  2. Proxy (climate) - Wikipedia

    en.wikipedia.org/wiki/Proxy_(climate)

    Reconstructions of global temperature of the past 2000 years, using composite of different proxy methods. In the study of past climates ("paleoclimatology"), climate proxies are preserved physical characteristics of the past that stand in for direct meteorological measurements [1] and enable scientists to reconstruct the climatic conditions over a longer fraction of the Earth's history.

  3. Glossary of geology - Wikipedia

    en.wikipedia.org/wiki/Glossary_of_geology

    Also called Indianite. A mineral from the lime-rich end of the plagioclase group of minerals. Anorthites are usually silicates of calcium and aluminium occurring in some basic igneous rocks, typically those produced by the contact metamorphism of impure calcareous sediments. anticline An arched fold in which the layers usually dip away from the fold axis. Contrast syncline. aphanic Having the ...

  4. Paleoclimatology - Wikipedia

    en.wikipedia.org/wiki/Paleoclimatology

    Paleoclimatology uses a variety of proxy methods from Earth and life sciences to obtain data previously preserved within rocks, sediments, boreholes, ice sheets, tree rings, corals, shells, and microfossils. Combined with techniques to date the proxies, the paleoclimate records are used to determine the past states of Earth's atmosphere.

  5. Glossary of geography terms (A–M) - Wikipedia

    en.wikipedia.org/wiki/Glossary_of_geography_terms...

    Also amphidrome and tidal node. A geographical location where there is little or no tide, i.e. where the tidal amplitude is zero or nearly zero because the height of sea level does not change appreciably over time (meaning there is no high tide or low tide), and around which a tidal crest circulates once per tidal period (approximately every 12 hours). Tidal amplitude increases, though not ...

  6. Speleothem - Wikipedia

    en.wikipedia.org/wiki/Speleothem

    Speleothem transects can provide paleoclimate records similar to those from ice cores or tree rings. [4] Slow geometrical growth and incorporation of radioactive elements enables speleothems to be accurately and precisely dated over much of the late Quaternary by radiocarbon dating and uranium-thorium dating , as long as the cave is a closed ...

  7. Principles of Geology - Wikipedia

    en.wikipedia.org/wiki/Principles_of_Geology

    Napoli, 1820, [1] which was based on a drawing by John Izard Middleton. [2] Principles of Geology: Being an Attempt to Explain the Former Changes of the Earth's Surface, by Reference to Causes Now in Operation is a book by the Scottish geologist Charles Lyell that was first published in 3 volumes

  8. Craton - Wikipedia

    en.wikipedia.org/wiki/Craton

    Cratons of South America and Africa during the Triassic Period when the two continents were joined as part of the Pangea supercontinent. A craton (/ ˈ k r eɪ t ɒ n / KRAYT-on, / ˈ k r æ t ɒ n / KRAT-on, or / ˈ k r eɪ t ən / KRAY-tən; [1] [2] [3] from Ancient Greek: κράτος kratos "strength") is an old and stable part of the continental lithosphere, which consists of Earth's two ...

  9. Discontinuity (geotechnical engineering) - Wikipedia

    en.wikipedia.org/wiki/Discontinuity...

    A discontinuity may exist as a single feature (e.g. fault, isolated joint or fracture) and in some circumstances, a discontinuity is treated as a single discontinuity although it belongs to a discontinuity set, in particular if the spacing is very wide compared to the size of the engineering application or to the size of the geotechnical unit.