The role of tephra in enhancing organic carbon preservation in marine sediments

Jack Longman*, Martin R. Palmer, Thomas M. Gernon, Hayley R. Manners

*Corresponding author for this work

Research output: Contribution to journalReview articlepeer-review

41 Citations (Scopus)

Abstract

Preservation of organic carbon (C org ) in marine sediments plays a major role in defining ocean-atmosphere CO 2 levels, Earth climate, and the generation of hydrocarbons. Important controls over sedimentary C org preservation include; biological productivity, C org isolation from oxidants (mainly dissolved O 2 ) in the overlying water column and sediments, and C org – mineral association in sediments. Deposition of the products of explosive volcanism (tephra) in the oceans directly enhances C org burial through all these mechanisms, and indirectly through enhanced formation of authigenic carbonate (C auth ) derived from sedimentary C org . In the modern oceans, it is suggested that tephra deposition may account for 5–10% of the C org burial flux and 10–40% of the C auth burial flux. However, during certain periods in Earth's history, extensive explosive volcanism may have led to enhanced C auth precipitation on a sufficiently large scale to influence the global ocean-atmosphere carbon cycle. Changes in tephra-related C org preservation may also have played a role in increasing C org preservation rates in local marine basins, at the oxic-anoxic boundary and enhanced the generation of hydrocarbon deposits in these settings.

Original languageEnglish
Pages (from-to)480-490
Number of pages11
JournalEarth-Science Reviews
Volume192
DOIs
Publication statusPublished - May 2019
Externally publishedYes

Fingerprint

Dive into the research topics of 'The role of tephra in enhancing organic carbon preservation in marine sediments'. Together they form a unique fingerprint.

Cite this