A far-field record of the end Ordovician glaciation: The Ellis Bay Formation, Anticosti Island, Eastern Canada

Desrochers, André; Farley, Claude; Achab, A.; Asselin, Esther; Riva, John

doi:10.1016/j.palaeo.2010.02.017

Cited by 102 publications

(93 citation statements)

References 37 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This pattern may indicate that environmental shifts at this time were generally more abrupt and severe in their effects on the biota than environmental shifts in the preceding approximately ten million years. Many stratigraphic sections record high-frequency relative sea-level oscillations during the late Katian-Hirnantian transition (49,50), and nearly all continuous sections record dramatic shallowing and/or changes in environmental conditions (51).…”

Section: Resultsmentioning

confidence: 99%

Climate change and the selective signature of the Late Ordovician mass extinction

Finnegan

Heim

Peters

et al. 2012

Proc. Natl. Acad. Sci. U.S.A.

148

113

View full text Add to dashboard Cite

Selectivity patterns provide insights into the causes of ancient extinction events. The Late Ordovician mass extinction was related to Gondwanan glaciation; however, it is still unclear whether elevated extinction rates were attributable to record failure, habitat loss, or climatic cooling. We examined Middle Ordovician-Early Silurian North American fossil occurrences within a spatiotemporally explicit stratigraphic framework that allowed us to quantify rock record effects on a per-taxon basis and assay the interplay of macrostratigraphic and macroecological variables in determining extinction risk. Genera that had large proportions of their observed geographic ranges affected by stratigraphic truncation or environmental shifts at the end of the Katian stage were particularly hard hit. The duration of the subsequent sampling gaps had little effect on extinction risk, suggesting that this extinction pulse cannot be entirely attributed to rock record failure; rather, it was caused, in part, by habitat loss. Extinction risk at this time was also strongly influenced by the maximum paleolatitude at which a genus had previously been sampled, a macroecological trait linked to thermal tolerance. A model trained on the relationship between 16 explanatory variables and extinction patterns during the early Katian interval substantially underestimates the extinction of exclusively tropical taxa during the late Katian interval. These results indicate that glacioeustatic sea-level fall and tropical ocean cooling played important roles in the first pulse of the Late Ordovician mass extinction in Laurentia.climate change | stratigraphy | sea level | Hirnantian | marine invertebrates T he Late Ordovician Mass Extinction (LOME) was the first of the "Big Five" Phanerozoic mass extinctions, and it eliminated an estimated 61% of marine genera globally (1). The LOME stands out among major mass extinctions in being unambiguously linked to climate change. The primary pulse of extinction near the Katian/Hirnantian stage boundary closely coincided with the rapid growth of south polar ice sheets on Gondwana (1-4). Expansion of continental ice sheets was accompanied by substantial cooling of the tropical oceans (5, 6), a major perturbation of the global carbon cycle (7-9) and a large drop in eustatic sea level (2, 5, 10, 11), which drained the vast cratonic seaways that characterized the Late Ordovician world (12). Extinction rates were particularly high around the tropical paleocontinent of Laurentia (13) where retreat of cratonic seas drove a sharp reduction in the area of preserved sedimentary rock between Katian and Hirnantian time (Fig. 1).The complex interrelated events surrounding the LOME exemplify a classic problem in paleobiology. Peaks in apparent extinction rate (14) are commonly associated with major gaps in the stratigraphic record or rapid changes in depositional environments. It is not always clear, however, whether these peaks simply reflect the spurious accumulation of last appearances at hiatal surfaces and lithofacies j...

show abstract

Section: Resultsmentioning

confidence: 99%

Climate change and the selective signature of the Late Ordovician mass extinction

Finnegan

Heim

Peters

et al. 2012

Proc. Natl. Acad. Sci. U.S.A.

148

113

View full text Add to dashboard Cite

show abstract

“…Biostratigraphic, chronostratigraphic, and sequence stratigraphic studies continue on strata from the Anticosti Section (e.g., Desrochers et al 2010). The stratigraphy from Copper and Long (1998) is used here; and it is clear that the Vauréal Formation represents the upper Katian, and all or most of the Ellis Bay Formation is within the Hirnantian.…”

Section: Anticosti Island Stratigraphymentioning

confidence: 99%

Ordovician–Silurian Lilliput crinoids during the end-Ordovician biotic crisis

Borths

Ausich

2010

Swiss J Palaeontol

View full text Add to dashboard Cite

Coincident with the end-Ordovician (end-Katian for crinoids) biodiversity crash, crinoids from Anticosti Island, Quebec, experienced a statistically significant reduction in body size, an evolutionary trend termed the ''Lilliput Effect''. This decrease in body size occurred for the fauna as a whole, and data indicate that neither dominant Ordovician nor dominant Silurian clades experienced preferential size decrease. Because the post-extinction fauna with a diminished size is composed of largely new taxa, this example of the Lilliput Effect is regarded as the miniaturization mode. The miniaturization occurred very rapidly; however, the recovery on Anticosti Island did not occur for as many as 7 Ma. This macroevolutionary asymmetry, as demonstrated in many other studies, highlights the need to preserve the biodiversity present on Earth today.

show abstract

“…Well-preserved Hirnantian limestones from Anticosti Island lack negative d 13 C anomalies below the Ordovician-Silurian boundary ( Fig. 3; Desrochers et al, 2010), despite generally covariant d 13 C and d 18 O (Long, 1993;Jones et al, 2011). Prolonged subaerial exposure and extensive karst development below the Middle Ordovician Knox unconformity in the Appalachians significantly depleted d 18 O but had a minimal effect on d 13 C (Mussman et al, 1988).…”

Section: Resultsmentioning

confidence: 94%

“…began in the Middle Ordovician (Saltzman and Young, 2005;Pope and Steffen, 2003) and lasted into the early Silurian, with a global sea-level fall during the Hirnantian Stage that may have equaled or exceeded that of the last glacial maximum . Sea-level changes resulting from Late Ordovician (Katian-Hirnantian) glacial cycles have been inferred based on transgressive-regressive stratigraphic sequences from the margins of Laurentia (e.g., Harris and Sheehan, 1997;Desrochers et al, 2010).…”

Section: Ordovician-silurian Icehousementioning

confidence: 99%

Chemostratigraphy of an Ordovician–Silurian carbonate platform: δ13C records below glacioeustatic exposure surfaces

Jones

Creel

Rios

et al. 2015

Geology

View full text Add to dashboard Cite

The use of carbon isotope stratigraphy to construct time lines for stratigraphic correlation requires synchronous changes in carbon isotope ratios (d 13 C) to be preserved in carbonatedominated strata. Such changes are commonly interpreted to reflect primary secular variation in ocean chemistry. However, negative d 13 C anomalies developed in Pliocene-Pleistocene carbonate platforms following glacioeustatic sea-level fall due to remineralization of terrestrial biomass during meteoric diagenesis. These anomalies are similar in structure and magnitude to some Neoproterozoic d 13 C records, opening the possibility that the Neoproterozoic d 13 C anomalies have a meteoric origin derived from a large terrestrial biosphere. Here we test the hypothesis that a large terrestrial biosphere existed prior to the Silurian-Devonian land-plant radiation by examining d 13 C records of subaerial exposure surfaces formed in a shallow-water carbonate platform during the Ordovician-Silurian icehouse. The exposure surfaces include an unconformity at the Ordovician-Silurian boundary with terra rossa and dissolution-collapse breccia, and a lower Silurian quartz sand layer feeding a 50-m-deep system of karst pipes. There is no evidence for d 13 C depletion beneath either exposure surface. Strontium concentrations in the rocks are low (10-120 ppm) and covary with d 18 O; oxygen isotope ratios, however, do not positively correlate with d 13 C. Our results suggest that there was no significant terrestrial biosphere during Ordovician-Silurian time, and by extension, that Neoproterozoic negative carbon isotope anomalies cannot be explained by meteoric diagenesis.

show abstract

A far-field record of the end Ordovician glaciation: The Ellis Bay Formation, Anticosti Island, Eastern Canada

Cited by 102 publications

References 37 publications

Climate change and the selective signature of the Late Ordovician mass extinction

Climate change and the selective signature of the Late Ordovician mass extinction

Ordovician–Silurian Lilliput crinoids during the end-Ordovician biotic crisis

Chemostratigraphy of an Ordovician–Silurian carbonate platform: δ13C records below glacioeustatic exposure surfaces

Contact Info

Product

Resources

About