Quantitative paleogeography and accretionary history, northern Appalachians

Title: Quantitative paleogeography and accretionary history, northern Appalachians

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Abstract

Ongoing paleomagnetic work on Early and Middle Paleozoic units provides quantitative data on paleogeography, latitudinal separation and latitudinal drift rates of tectonic elements that characterize the history of the northern segment of the Appalachian orogen. Following rifting and opening of Iapetus, the southern margin of Laurentia moved from ca 15S in the Ordovician to ca. 30S in the late Silurian: the northern margin of Avalon drifted northward (separate from Gondwana) from > 50--30S during the same time interval. Paleolatitudes from volcanic units of the intervening Central Mobile Belt that yield primary magnetizations are: Newfoundland: Ordovician arc-back arc basin: 11[degree]S; Ordovician ocean island/arc: 31[degree]S; Silurian continental cover: Botwood Gp: 24[degree]S, Springdale Gp: 17[degree]S New Brunswick: Ordovician rift-subduction complex: 53[degree]S. Maine: Munsungun Volcanic Terrane 18[degree]S; Winterville Volcanic Terrane 15--20[degree]S; upper part Lunksoos Composite Terrane: 20[degree]S. The Ordovician results indicate several near-Laurentian volcanic terranes and back-arc basins, landward-dipping subduction complexes on opposite margins of Iapetus, and intra-Iapetus ocean islands/arcs. Silurian paleogeographic and tectonostratigraphic data show that closure of Iapetus and progressive outboard accretion in the northern portion of the Appalachian orogen was complete by the late Silurian. This closure is accompanied by considerable Ordovician to Early Silurian left-lateral strike slip and subsequent right-lateralmore »« less

Authors:

Pluijm, B.A. van der; Voo, R van der ^[1]

Univ. of Michigan, Ann Arbor, MI (United States). Dept. of Geological Sciences

Publication Date:: 1992-01-01

OSTI Identifier:: 5807779

Report Number(s):: CONF-921058-
Journal ID: ISSN 0016-7592; CODEN: GAAPBC

Resource Type:: Conference

Journal Name:: Geological Society of America, Abstracts with Programs; (United States)

Additional Journal Information:: Journal Volume: 24:7; Conference: 1992 annual meeting of the Geological Society of America (GSA), Cincinnati, OH (United States), 26-29 Oct 1992; Journal ID: ISSN 0016-7592

Country of Publication:: United States

Language:: English

Subject:: 58 GEOSCIENCES; APPALACHIAN MOUNTAINS; OROGENESIS; GEOGRAPHY; MAINE; NEW BRUNSWICK; NEWFOUNDLAND; ORDOVICIAN PERIOD; PALEOMAGNETISM; PLATE TECTONICS; SILURIAN PERIOD; CANADA; DEVELOPED COUNTRIES; GEOLOGIC AGES; ISLANDS; MAGNETISM; MOUNTAINS; NORTH AMERICA; PALEOZOIC ERA; TECTONICS; USA; 580000* - Geosciences

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                    Pluijm, B.A. van der, and Voo, R van der. Quantitative paleogeography and accretionary history, northern Appalachians.  United States: N. p., 1992. 
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                    Pluijm, B.A. van der, & Voo, R van der. Quantitative paleogeography and accretionary history, northern Appalachians.  United States.

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                    Pluijm, B.A. van der, and Voo, R van der. Wed .  
        "Quantitative paleogeography and accretionary history, northern Appalachians".  United States.

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@article{osti_5807779,

  title        = {Quantitative paleogeography and accretionary history, northern Appalachians},

  author       = {Pluijm, B.A. van der and Voo, R van der},

  abstractNote = {Ongoing paleomagnetic work on Early and Middle Paleozoic units provides quantitative data on paleogeography, latitudinal separation and latitudinal drift rates of tectonic elements that characterize the history of the northern segment of the Appalachian orogen. Following rifting and opening of Iapetus, the southern margin of Laurentia moved from ca 15S in the Ordovician to ca. 30S in the late Silurian: the northern margin of Avalon drifted northward (separate from Gondwana) from > 50--30S during the same time interval. Paleolatitudes from volcanic units of the intervening Central Mobile Belt that yield primary magnetizations are: Newfoundland: Ordovician arc-back arc basin: 11[degree]S; Ordovician ocean island/arc: 31[degree]S; Silurian continental cover: Botwood Gp: 24[degree]S, Springdale Gp: 17[degree]S New Brunswick: Ordovician rift-subduction complex: 53[degree]S. Maine: Munsungun Volcanic Terrane 18[degree]S; Winterville Volcanic Terrane 15--20[degree]S; upper part Lunksoos Composite Terrane: 20[degree]S. The Ordovician results indicate several near-Laurentian volcanic terranes and back-arc basins, landward-dipping subduction complexes on opposite margins of Iapetus, and intra-Iapetus ocean islands/arcs. Silurian paleogeographic and tectonostratigraphic data show that closure of Iapetus and progressive outboard accretion in the northern portion of the Appalachian orogen was complete by the late Silurian. This closure is accompanied by considerable Ordovician to Early Silurian left-lateral strike slip and subsequent right-lateral displacement based on the relative positions of Laurentia, Avalon and Gondwana in Early and Middle Paleozoic times.},

  doi          = {},

  url          = {https://www.osti.gov/biblio/5807779},
  journal      = {Geological Society of America, Abstracts with Programs; (United States)},

  issn         = {0016-7592},

  number       = ,

  volume       = 24:7,

  place        = {United States},

  year         = {1992},

  month        = {1}

}

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