Tippecanoe sequence

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The Tippecanoe sequence was the cratonic sequence--that is, the marine transgression--that followed the Sauk sequence; it extended from roughly the Middle Ordovician to the Early Devonian.

Sedimentary characteristics[edit]

After the regression of the Sauk Sea early in the Ordovician, the exposed craton for a time underwent vigorous erosion, due to being located in a tropical climate; indeed, at this point in the Phanerozoic the North American continent roughly straddled the equator.[1]

The Tippecanoe transgression ended this period of erosion, beginning with the deposition of clean sandstones across the craton, followed by abundant carbonate deposition.[2] In the east these carbonates gradually become shales, representing sediments eroded from highlands created in the Taconic orogeny.[2]

The Tippecanoe sequence may have been the deepest of the Phanerozoic. At one point during the Silurian period, the Taconic highlands—which later became the Appalachian Mountains--were the only part of North America that was not submerged.[3] The massive evaporite deposits of the Michigan Basin were created during this period.[4]

The Tippecanoe sequence ended with a regression in the early Devonian, to be followed later by the Kaskaskia sequence.

References[edit]

  1. ^ Monroe, James S., and Reed Wicander. The Changing Earth: Exploring Geology and Evolution, 2nd ed. Belmont: West Publishing Company, 1997. ISBN 0-314-09577-2 pp. 533-4
  2. ^ a b Monroe and Wicander, pp. 534-5
  3. ^ Monroe and Wicander, p. 537
  4. ^ Monroe and Wicander, pp. 537-8