Indian Point Formation

Indian Point Formation
Stratigraphic range: Ludlow epoch
~423–419 Ma
↓
TypeFormation
UnderliesArchibald Settlement Formation
Lithology
PrimarySandstone, siltstone, calcarenite
OtherBiostromal limestone, conglomerate, mafic volcanic rock
Location
Coordinates48°48′N 64°30′W / 48.8°N 64.5°W / 48.8; -64.5
Approximate paleocoordinates26°36′S 29°42′W / 26.6°S 29.7°W / -26.6; -29.7
RegionQuebec
Country Canada
ExtentGaspe National Park
Indian Point Formation is located in Canada
Indian Point Formation
Indian Point Formation (Canada)
Indian Point Formation is located in Quebec
Indian Point Formation
Indian Point Formation (Quebec)

The Indian Point Formation is a geologic formation in Quebec. It preserves fossils dating back to the Ludlow epoch of the Silurian period.[1]

Description

The Indian Point Formation comprises thin- to thick-bedded, locally fossiliferous, calcareous siltstones, fine-grained sandstones, calcarenites, and minor biostromal limestones, conglomerates, red siltstones, and mafic volcanic rocks. The Indian Point Formation is conformably overlain by within-plate tholeiitic mafic to intermediate flows and flow breccias of the Archibald Settlement Formation, developed as a synsedimentary normal fault in the Late Silurian, based on the presence of polymictic conglomerate beds in a thickened Indian Point section east of the fault. Post-Early Devonian (Acadian) orogenic events have produced open to close folds with northeast-trending axes.[2]

Fossil content

The following fossils were reported from the formation:[1][3]

Eurypterids

Pterobranchia

See also

References

  1. ^ a b Indian Point Formation at Fossilworks.org
  2. ^ Eurypterid-associated biota of Indian Point Fmn. in Gaspe National Park at Fossilworks.org
  3. ^ Plotnick, 1999

Bibliography

  • Plotnick, R. E (1999), Habitat of Llandoverian-Lochkovian eurypterids, in A. J. Boucot, J. D. Lawson (eds.), Paleocommunities - a case study from the Silurian and Lower Devonian, pp. 106–136