Bed (geology)

Layer of sediment, sedimentary rock, or pyroclastic material

In geology, a bed is a layer of sediment, sedimentary rock, or volcanic rock "bounded above and below by more or less well-defined bedding surfaces". A bedding surface or bedding plane is respectively a curved surface or plane that visibly separates each successive bed (of the same or different lithology) from the preceding or following bed. In cross sections, bedding surfaces or planes are often called bedding contacts.

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