Journal article
The rise of pinnacle reefs: A step change in marine evolution triggered by perturbation of the global carbon cycle
Earth and planetary science letters, Vol.515, pp.13-25
06/01/2019
DOI: 10.1016/j.epsl.2019.02.039
Abstract
•First Silurian pinnacle reef tracts coincident with Manitowoc δ13Ccarb excursion.•Pinnacle reefs form above sequence boundaries during positive δ13Ccarb excursions.•Growth of pinnacle reefs driven by rapid sea level rise and calcification overshoot.•Reefs increasingly coincide with positive δ13Ccarb excursions in early Paleozoic.•Lockstep distribution of pinnacles and δ13Ccarb excursions: mid-Telychian onward.
The first appearance of pinnacle reef tracts, composed of hundreds to thousands of localized biogenic structures protruding tens to hundreds of meters above the surrounding mid-Silurian seafloor, represents a step change in the evolution of the marine biosphere. This change in seafloor morphology opened a host of new ecological niches that served as “evolutionary cradles” for organism diversification. However, the exact timing and drivers of this event remain poorly understood. These uncertainties remain, in large part, due to a paucity of index fossils in the reef facies, the difficulty of correlating between the offshore pinnacle reefs and more temporally well-constrained shallow marine facies, and cryptic unconformities that separate amalgamated reefs. Here we use δ13Ccarb stratigraphy within a sequence stratigraphic framework to unravel these complex relationships and constrain the origination of Silurian pinnacle reef tracts in the North American midcontinent to near the Pt. celloni Superzone—Pt. am. amorphognathoides Zonal Group boundary of the mid-Telychian Stage.
In addition, we identify a striking relationship between pulses of reef development and changes in global δ13Ccarb values and sea level. Viewed through this new perspective, we correlate prolific periods of reef development with short-lived carbon isotope (δ13Ccarb) excursions and eustatic sea level change that, ultimately, reflect perturbations to the global carbon cycle. From changes in the dominance of microbial reefs of the Cambrian to metazoan colonization of reefs in the Middle Ordovician, through the subsequent collapse of metazoan diversity with the Late Ordovician mass extinction, and the first appearance of early Silurian (Llandovery) pinnacle reef tracts and their proliferation during the late Silurian (Wenlock-Pridoli) and Devonian, major reef formation intervals increasingly coincide with δ13Ccarb excursions. These patterns suggest that Paleozoic reef evolution was the product of environmental forcing by perturbations of the global carbon cycle.
Details
- Title: Subtitle
- The rise of pinnacle reefs: A step change in marine evolution triggered by perturbation of the global carbon cycle
- Creators
- Patrick I. McLaughlin - Indiana Geological and Water SurveyPoul Emsbo - United States Geological SurveyCarlton E. Brett - University of CincinnatiAlyssa M. Bancroft - Indiana Geological and Water SurveyAndré Desrochers - University of OttawaThijs R.A. Vandenbroucke - Ghent University
- Resource Type
- Journal article
- Publication Details
- Earth and planetary science letters, Vol.515, pp.13-25
- Publisher
- Elsevier B.V
- DOI
- 10.1016/j.epsl.2019.02.039
- ISSN
- 0012-821X
- eISSN
- 1385-013X
- Number of pages
- 13
- Language
- English
- Date published
- 06/01/2019
- Academic Unit
- Earth and Environmental Sciences; Iowa Geological Survey; IIHR--Hydroscience and Engineering
- Record Identifier
- 9984701820302771
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