When.com Web Search

Search results

  1. Results From The WOW.Com Content Network
  2. Allotropes of carbon - Wikipedia

    en.wikipedia.org/wiki/Allotropes_of_carbon

    Lonsdaleite is an allotrope sometimes called "hexagonal diamond", formed from graphite present in meteorites upon their impact on the earth. The great heat and pressure of the impact transforms the graphite into a denser form similar to diamond but retaining graphite's hexagonal crystal lattice. "Hexagonal diamond" has also been synthesized in ...

  3. Overburden - Wikipedia

    en.wikipedia.org/wiki/Overburden

    Overburden is also used for all soil and ancillary material above the bedrock horizon in a given area. By analogy, overburden is also used to describe the soil and other material that lies above a specific geologic feature , such as a buried astrobleme , or above an unexcavated site of archeological interest.

  4. Llewellyn Formation - Wikipedia

    en.wikipedia.org/wiki/Llewellyn_Formation

    The bottom of the formation is placed either at the bottom of Buck Mountain (no. 5) coal bed or at the bottom of the underclay or shale bed below this coal measure. Since this is the last bed deposited in the Appalachian Basin in eastern Pennsylvania that still exists, only recent alluvial and colluvial deposits rest on top.

  5. Parent material - Wikipedia

    en.wikipedia.org/wiki/Parent_material

    Parent material is the underlying geological material (generally bedrock or a superficial or drift deposit) in which soil horizons form. Soils typically inherit a great deal of structure and minerals from their parent material, and, as such, are often classified based upon their contents of consolidated or unconsolidated mineral material that has undergone some degree of physical or chemical ...

  6. Coke (fuel) - Wikipedia

    en.wikipedia.org/wiki/Coke_(fuel)

    Raw coke. Coke is a grey, hard, and porous coal-based fuel with a high carbon content. It is made by heating coal or petroleum in the absence of air. Coke is an important industrial product, used mainly in iron ore smelting, but also as a fuel in stoves and forges.

  7. Allegheny Group - Wikipedia

    en.wikipedia.org/wiki/Allegheny_group

    The Allegheny Group, often termed the Allegheny Formation, [2] is a Pennsylvanian-age geological unit in the Appalachian Plateau.It is a major coal-bearing unit in the eastern United States, extending through western and central Pennsylvania, western Maryland and West Virginia, and southeastern Ohio.

  8. Allotropy - Wikipedia

    en.wikipedia.org/wiki/Allotropy

    Diamond and graphite are two allotropes of carbon: pure forms of the same element that differ in crystalline structure.. Allotropy or allotropism (from Ancient Greek ἄλλος (allos) ' other ' and τρόπος (tropos) ' manner, form ') is the property of some chemical elements to exist in two or more different forms, in the same physical state, known as allotropes of the elements.

  9. File:Geologic Map of Minnesota- Bedrock Geology (2011).pdf

    en.wikipedia.org/wiki/File:Geologic_Map_of...

    Minnesota Geological Survey via Minnesota Geologic Topics; select Bedrock Geology, then select Geologic Map of Minnesota's Bedrock Geology: Author: Mark A. Jirsa, Terrence J. Boerboom, V.W. Chandler, John H. Mossler, Anthony C. Runkel, and Dale R. Setterholm: Permission (Reusing this file)