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Where did Ordovician sandstone and conglomerate deposits form?
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Ordovician Period
The distribution of landmasses, mountainous regions, shallow seas, and deep ocean basins during the Ordovician Period. Included in the paleogeographic reconstruction are the locations of the interval's subduction zones.
During the Ordovician Period, coarse-grained siliciclastic rocks, such as sandstones and conglomerates, formed in two primary settings:
- High latitudes: These deposits accumulated in regions where significant carbonate accumulation was precluded.1
- Low latitudes: These formed in areas where orogenic uplift provided abundant sediment.1
In North America, significant accumulations occurred in the Appalachians due to the Taconic orogeny, which supplied sediment to the Queenston Delta. Additionally, the Middle Ordovician Saint Peter Sandstone formed as a vast coastal sand dune system across much of North America. On other continents, thick successions of sandstones are found in regions associated with Gondwana, including Antarctica, Australia, Great Britain, southern Europe, South America, and Africa. Furthermore, coarse siliciclastic rocks occur as glacial deposits in the late Late Ordovician of Africa and South America.1