Skip to Main Content
Skip Nav Destination
GEOREF RECORD

Modelling the impact of pulsed CAMP volcanism on pCO (sub 2) and delta (super 13) C across the Triassic-Jurassic transition

Aviv Bachan and Jonathan L. Payne
Modelling the impact of pulsed CAMP volcanism on pCO (sub 2) and delta (super 13) C across the Triassic-Jurassic transition (in Mass extinctions, Bas van de Schootbrugge (prefacer) and Paul B. Wignall (prefacer))
Geological Magazine (March 2016) 153 (2): 252-270

Abstract

A sharp negative delta (super 13) C excursion coincides with the end-Triassic mass extinction. This is followed by a protracted interval of (super 13) C enrichment. These isotopic events occurred simultaneously with the emplacement of the Central Atlantic Magmatic Province (CAMP). Here we use a carbon cycle box model to explore the effects of episodic carbon release--constrained by recently developed high-resolution chronology - on atmospheric pCO (sub 2) , ocean chemistry and the delta (super 13) C of the ocean-atmosphere carbon pool. Our results are consistent with previous modelling efforts in suggesting that the sharp negative delta (super 13) C excursion and acidification event associated with the extinction are best explained by the rapid release (<20 ka) of highly (super 13) C-depleted carbon (-70 ppm). However, our model also indicates that the likely short duration of the excursion requires organic carbon burial to have closely followed carbon injection. The age within the Hettangian of the large positive delta (super 13) C excursion which follows is currently uncertain. If early Hettangian in age, then our modelling indicates that the interval of (super 13) C enrichment was closely associated with the volcanic CO (sub 2) pulses and pCO (sub 2) peaks. If late Hettangian in age, then the (super 13) C enrichment must have lagged the carbon input substantially (by hundreds of thousands of years) and was associated with CO (sub 2) drawdown and over-cooling. Our modelling highlights the need for improved age constraints on Hettangian stratigraphic sections in order to test between two distinct and contrasting possibilities: continuing carbon cycle instability due to recurrent perturbations from CAMP activity or a delayed recovery arising from internal biosphere dynamics.


ISSN: 0016-7568
EISSN: 1469-5081
Coden: GEMGA4
Serial Title: Geological Magazine
Serial Volume: 153
Serial Issue: 2
Title: Modelling the impact of pulsed CAMP volcanism on pCO (sub 2) and delta (super 13) C across the Triassic-Jurassic transition
Title: Mass extinctions
Author(s): Bachan, AvivPayne, Jonathan L.
Author(s): van de Schootbrugge, Basprefacer
Author(s): Wignall, Paul B.prefacer
Affiliation: Stanford University, Department of Geological and Environmental Sciences, Stanford, CA, United States
Affiliation: Utrecht University, Institute of Earth Sciences, Netherlands
Pages: 252-270
Published: 201603
Text Language: English
Publisher: Cambridge University Press, London, United Kingdom
References: 126
Accession Number: 2016-028271
Categories: General geochemistryStratigraphy
Document Type: Serial
Bibliographic Level: Analytic
Illustration Description: illus. incl. 3 tables
Secondary Affiliation: University of Leeds, GBR, United Kingdom
Country of Publication: United Kingdom
Secondary Affiliation: GeoRef, Copyright 2017, American Geosciences Institute. Abstract, Copyright, Cambridge University Press. Reference includes data from GeoScienceWorld, Alexandria, VA, United States
Update Code: 201614
Close Modal

or Create an Account

Close Modal
Close Modal