Tephrostratigraphy and radiometric dating of authigenic carbonates

DOI

At convergent margins, fluids rise through the forearc in response to consolidation of the upper plate and dewatering of the subducting plate, and produce various cold-seep-related features on the seafloor (mud diapirs, mud mounds). At the Central American forearc, authigenic carbonates precipitated from rising fluids within such structures during active venting while typical mixed-mud sediments were ejected onto the surrounding seafloor where they became intercalated with normal pelagic background sediments, indicating that mud mounds evolved unsteadily through alternating active and inactive phases. Intercalated regional ash layers from Plinian eruptions at the Central American volcanic arc provide time marks that constrain the ages of mud ejection activity. U/Th dating of drill core samples of authigenic carbonate caps of mud mounds yields ages agreeing well with those constrained by ash layers and showing that carbonate caps grow inward rather than outward during active venting.Both dating approaches show that offshore Nicaragua and Costa Rica (1) active and inactive phases can occur simultaneously at neighboring mounds, (2) mounds along the forearc have individual histories of activity, but there are distinct time intervals when nearly all mounds have been active or inactive, (3) lifetimes of mounds reach several hundred thousand years, and (4) highly active periods last 10-50 k.y. with intervening periods of >10 k.y. of relative quiescence.

Supplement to: Kutterolf, Steffen; Liebetrau, Volker; Mörz, Tobias; Freundt, Armin; Hammerich, Thomas; Garbe-Schönberg, Dieter (2008): Lifetime and cyclicity of fluid venting at forearc mound structures determined by tephrostratigraphy and radiometric dating of authigenic carbonates. Geology, 36, 707-710

Identifier
DOI https://doi.org/10.1594/PANGAEA.789040
Related Identifier https://doi.org/10.1130/G24806A.1
Metadata Access https://ws.pangaea.de/oai/provider?verb=GetRecord&metadataPrefix=datacite4&identifier=oai:pangaea.de:doi:10.1594/PANGAEA.789040
Provenance
Creator Kutterolf, Steffen ORCID logo; Liebetrau, Volker; Mörz, Tobias; Freundt, Armin ORCID logo; Hammerich, Thomas; Garbe-Schönberg, Dieter ORCID logo
Publisher PANGAEA
Publication Year 2012
Funding Reference German Research Foundation https://doi.org/10.13039/501100001659 Crossref Funder ID 5484524 https://gepris.dfg.de/gepris/projekt/5484524 Volatiles and Fluids in Subduction Zones
Rights Creative Commons Attribution 3.0 Unported; https://creativecommons.org/licenses/by/3.0/
OpenAccess true
Representation
Language English
Resource Type Supplementary Publication Series of Datasets; Collection
Format application/zip
Size 19 datasets
Discipline Earth System Research
Spatial Coverage (-87.265W, 8.922S, -84.304E, 11.279N)
Temporal Coverage Begin 2002-09-02T18:40:00Z
Temporal Coverage End 2005-11-05T10:50:00Z