Beardmore orogeny

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The Beardmore orogeny was a mountain building event in the Neoproterozoic affecting what is now Antarctica. The event is preserved in the Trans-Antarctic Mountains, potentially in the Shackleton Range and by argillite-greywacke series in the Horlick Mountains, Queen Maud Land and the Thiel Mountains. Upright folds, asymmetric overturned or recumbent isoclinal folds first identified by Elliott in 1975 was interpreted in 1992 by Edmund Stump as indicative of compressive and convergent tectonic activity. [1]

The orogeny is expressed as an unconformity in the Transantarctic Mountains, between folded Late Proterozoic strata and overlying Early or Middle Cambrian sediments. This Late Precambrian event occurred between 660 and 580 Ma. [2]

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Yavapai orogeny Mountain building event 1.7 billion years ago in the southerwestern United States

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The Picuris orogeny was an orogenic event in what is now the Southwestern United States from 1.43 to 1.3 billion years ago in the Calymmian Period of the Mesoproterozoic. The event is named for the Picuris Mountains in northern New Mexico and interpreted either as the suturing of the Granite-Rhyolite crustal province to the southern margin of the proto-North American continent Laurentia or as the final suturing of the Mazatzal crustal province onto Laurentia. According to the former hypothesis, this was the second in a series of orogenies within a long-lived convergent boundary along southern Laurentia that ended with the ca. 1200–1000 Mya Grenville orogeny during the final assembly of the supercontinent Rodinia, which ended an 800-million-year episode of convergent boundary tectonism.

References

  1. Anderson, John B. (1999). "Antarctic Marine Geology". Cambridge University Press. p. 30-32. ISBN   9780521593175.
  2. Laird, Malcolm (1991). Tingey, Robert (ed.). The Late Proterozoic-Middle Palaeozoic rocks of Antarctica, in The Geology of Antarctica. Oxford: Clarendon Press. pp. 82–83, 104, 108. ISBN   0198544677.