Vampire Formation

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Vampire Formation
Stratigraphic range: Cambrian
Type Geological formation
UnderliesSekwi Formation
OverliesIngta Formation
Thicknessup to
Location
LocationMackenzie Mountains
RegionFlag of the Northwest Territories.svg  Northwest Territories
CountryFlag of Canada (Pantone).svg  Canada

The Vampire Formation is a formation of delta-front siliciclastics deposited in the early Cambrian. The upper unit is trilobitic Cambrian. [1] Some authors place the underlying Ingta formation at least partially in the Cambrian; in places it overlies the sub-Cambrian unconformity. [2]

It contains a rich array of trace fossils spanning the pre-trilobitic Cambrian, [3] including some found only there (once interpreted as sponge-like forms); [4] its uppermost strata contain Fallotaspis-zone trilobites, whereas its lower levels come above Protohertzina and Anabarites-bearing shelly layers in the Ingta formation; as such, it spans much of the Fortunian. [5]

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References

  1. MacNaughton, Robert; Dalrymple, Robert; Narbonne, Guy (1997). "Early Cambrian braid-delta deposits, Mackenzie Mountains, north-western Canada". Sedimentology. 44 (4): 587–609. Bibcode:1997Sedim..44..587M. doi:10.1046/j.1365-3091.1997.d01-41.x.
  2. MacNaughton, Robert; Dalrymple, Robert; Narbonne, Guy (1997). "Early Cambrian braid-delta deposits, Mackenzie Mountains, north-western Canada". Sedimentology. 44 (4): 587–609. Bibcode:1997Sedim..44..587M. doi:10.1046/j.1365-3091.1997.d01-41.x.
  3. MacNaughton, Robert B.; Narbonne, Guy M. (1 April 1999). "Evolution and ecology of Neoproterozoic-Lower Cambrian trace fossils, NW Canada". PALAIOS. 14 (2): 97–115. doi:10.2307/3515367.
  4. Hofmann, H. J. (1983). "Early Cambrian problematic fossils near June Lake, Mackenzie Mountains, N.W.T.". Canadian Journal of Earth Sciences. 20 (10): 1513–1520. Bibcode:1983CaJES..20.1513H. doi:10.1139/e83-140.
  5. Pyle, Leanne J.; Narbonne, Guy M.; James, Noel P.; Dalrymple, Robert W.; Kaufman, Alan J. (2004). "Integrated Ediacaran chronostratigraphy, Wernecke Mountains, northwestern Canada". Precambrian Research. 132 (1–2): 1–27. Bibcode:2004PreR..132....1P. doi:10.1016/j.precamres.2004.01.004.