Title | The crinoid Marsupites in the Upper Cretaceous Nanaimo Group, British Columbia: resolution of the Santonian-Campanian boundary in the North Pacific Province |
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Author | Haggart, J W; Graham, R |
Source | Cretaceous Research vol. 87, 2017 p. 277-295, https://doi.org/10.1016/j.cretres.2017.05.029 |
Links | Erratum
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Year | 2017 |
Alt Series | Natural Resources Canada, Contribution Series 20170032 |
Publisher | Elsevier BV |
Document | serial |
Lang. | English |
Media | paper; on-line; digital |
Related | This publication is accompanied by Erratum to 'The crinoid
Marsupites in the Upper Cretaceous Nanaimo Group, British Columbia: resolution of the Santonian-Campanian boundary in the North Pacific Province,' Cretaceous Research, v. 87, pp. 277-295 |
File format | pdf (Adobe® Reader®); doc (Microsoft® Word®) |
Province | British Columbia |
NTS | 92C; 92B; 92F; 92G/02; 92G/03; 92G/04 |
Area | Vancouver Island; Nanaimo; Tsable River; NOrthwest Bay; Haslam Creek; Duncan |
Lat/Long WENS | -125.5000 -123.0000 50.0000 48.7500 |
Subjects | paleontology; stratigraphy; fossils; endemic faunas; biostratigraphy; Upper Cretaceous; Santonian; Campanian; fossil assemblages; stratigraphic correlations; magnetostratigraphy; index fossils; fossil
zones; continental margins; continental slope; fossil morphology; Molluscs; Sphenoceramus orientalis; Sphenoceramus elegans; Sphenoceramus sachalinensis; Crinoids; Marsupites; Nanaimo Group; Haslam Formation; Marsupites testudinarius; Marsupites
lamberti; proto-Pacific Ocean; Ammonites; Pseudoschloenbachia umbulazi; Eupachydiscus haradai usheri; Inoceramids; Bivalves; Pacific Continental Margin; Pacific Slope; Submortoniceras; Phanerozoic; Mesozoic; Cretaceous |
Illustrations | location maps; stratigraphic charts; schematic diagrams; photomicrographs; tables |
Program | Science laboratory network |
Released | 2017 05 30 |
Abstract | The strongly endemic nature of Late Cretaceous molluscan faunas of the North Pacific region creates challenges for correlation of stratigraphic sections in basins surrounding the proto-Pacific Ocean
with European standard successions. A particularly problematic stage boundary in the Pacific region is the SantonianeCampanian boundary, which is poorly defined in the northwest and northeast Pacific regions on the basis of local ammonite and
inoceramid bivalve assemblages or poorly constrained magnetostratigraphy. Examples of the crinoid genus Marsupites Mantell in Miller 1821, considered a marker of the SantonianeCampanian boundary at many places around the globe, have been collected
recently from a number of localities of the Upper Cretaceous Nanaimo Group succession of southwestern British Columbia, including the species M. testudinarius and M. lamberti. Co-occurring specimens of Marsupites testudinarius in the Nanaimo Group
include both smooth and coarsely ornamented forms which do not show stratigraphic segregation, suggesting that M. testudinarius is a morphologically-variable species which includes forms that were attributed to different species by previous workers.
The presence of M. testudinarius in stratigraphic sections of the Nanaimo Group allows the precise placement of the SantonianeCampanian boundary interval in the Nanaimo Group succession, and correlation of this boundary with the European standard
succession. As well, the occurrence of the crinoid allows for revision of the biostratigraphic zonation of the upper Santonianelower Campanian interval in the Nanaimo Group. Characteristic molluscan assemblages which are found in association with
M. testudinarius in the Nanaimo Group are known to occur elsewhere along the North American Pacific slope (e.g., northern California, USA), as well as in the northwest Pacific region (Japan, Sakhalin, Koryakia), and thus provide a marker for the
SantonianeCampanian boundary in those areas where Marsupites has not yet been found. |
Summary | (Plain Language Summary, not published) The authors have identified a fossil echinoderm in sedimentary rocks of Late Cretaceous age, about 84 million years old, on Vancouver Island in
southwestern British Columbia. This is the first time this fossil crinoid has been recognized in the Pacific Rim region. The fossil has been widely known previously in northern Europe, where it is considered to be a marker fossil for the boundary of
the Santonian and Campanian age interval of the Late Cretaceous. Its recognition in rocks of Vancouver Island allows geologists to directly correlate the Santonian/Campanian boundary interval in rocks of western Canada with the succession of northern
Europe, and to also identify likely intervals in other areas of the Pacific Rim where the boundary should be found. |
GEOSCAN ID | 300671 |
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