Chapel Island Formation

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Chapel Island Formation
Stratigraphic range: Terminal Ediacaran – Fortunian[1]
Cambrian GSSP in Chapel Island Formation.jpg
Ediacaran-Cambrian boundary section at Fortune Head, NL, in the Chapel Island Fm. The darker units constituting the bottom c. 2-3 m of the outcrop correspond to unit 1; the GSSP lies a couple of m into Unit 2.
Type Formation
Unit of Young's Cove Group[2]
Underlies Random Fm[3]
Overlies Rencontre Fm[3]
Thickness Hundreds of metres[3]
Location
Region Newfoundland
Country Canada
Chapel Island Formation map.svg
Outcrop distribution in southeast Newfoundland

The Chapel Island Formation is a sedimentary formation from the Burin Peninsula, Newfoundland, Canada. It is an over 1000 meter thick succession of siliciclastic deposits that were deposited during the latest Ediacaran and earliest Cambrian.

Stratigraphy[edit]

Sequence stratigraphy shown here:[4] The formation starts in an intertidal zone, then as the Cambrian progresses, it becomes deeper water (outer shelf) as a general trend. The Chapel Island Formation lies on top of the Rencontre Formation and below the Random Formation.[5] It is 900 m thick in Fortune Bay as a fault-bounded basin, ; grey-green siltstones and sandstones, with minor limestone beds near its top. Small Shelly Fossils have been recovered - primitive taxa only. Setting nearshore or open shelf.[3]

Subdivision[edit]

The Formation is divided into six members, numbered 1 to 5, with member 2 split into 2A and 2B. The Proterozoic/Cambrian-boundary occurs 20.66 m above the base of the CIF, 2.4 m into Member 2A.[5]

The lowest occurrence of T.pedum in the succession is 16.25 m above the base of the unit.[6]


Overview of sedimentology and facies available in [7]:1282

References[edit]

  1. ^ Gehling, James G.; Jensen, Sören; Droser, Mary L.; Myrow, Paul M.; Narbonne, GUY M. (2001). "Burrowing below the basal Cambrian GSSP, Fortune Head, Newfoundland". Geological Magazine. 138 (2). doi:10.1017/S001675680100509X. 
  2. ^ "Newfoundland and Labrador Geoscience Atlas". 
  3. ^ a b c d Smith, Simon A.; Hiscott, Richard N. (December 1984). "Latest Precambrian to Early Cambrian basin evolution, Fortune Bay, Newfoundland: fault-bounded basin to platform". Canadian Journal of Earth Sciences. 21 (12): 1379–1392. Bibcode:1984CaJES..21.1379S. doi:10.1139/e84-143. 
  4. ^ Myrow, Paul M.; Hiscott, Richard N. (September 1993). "Depositional history and sequence stratigraphy of the Precambrian-Cambrian boundary stratotype section, Chapel Island Formation, southeast Newfoundland". Palaeogeography, Palaeoclimatology, Palaeoecology. 104 (1–4): 13–35. doi:10.1016/0031-0182(93)90117-2. 
  5. ^ a b Gehling, James G.; Sören Jensen; Mary L. Droser; Paul M. Myrow; Guy M. Narbonne (2001). "Burrowing below the basal Cambrian GSSP, Fortune Head, Newfoundland" (PDF). Geological Magazine. 213-218. 138. Archived from the original (PDF) on 28 October 2014. Retrieved 3 November 2012. 
  6. ^ Gehling, James G.; Jensen, Sören; Droser, Mary L.; Myrow, Paul M.; Narbonne, GUY M. (2001). "Burrowing below the basal Cambrian GSSP, Fortune Head, Newfoundland". Geological Magazine. 138 (2). doi:10.1017/S001675680100509X. 
  7. ^ Narbonne, G.M., Myrow, P.M., Landing, E., and Anderson, M.M. (1987). A candidate stratotype for the Precambrian- Cambrian boundary, Fortune Head, Burin Peninsula, southeastern Newfoundland. Can. J. Earth Sci. 24, 1277–1293.