Paleo-Fluid Expulsion Influencing Contouritic Drift Formation on the Chatham Rise, New Zealand.

Waghorn, Kate, Pecher, Ingo, Strachan, Lorna, Crutchley, Gareth, Bialas, Jörg, Coffin, Richard, Davy, Bryan, Koch, Stephanie, Kroeger, Karsten F., Papenberg, Cord, Rose, Paula and Sarkar, Sudipta and SO226 Scientific Party (2017) Paleo-Fluid Expulsion Influencing Contouritic Drift Formation on the Chatham Rise, New Zealand. Basin Research . DOI 10.1111/bre.12237.

[img] Text
Waghorn.pdf - Accepted Version
Restricted to Registered users only

Download (13Mb) | Contact

Supplementary data:

Abstract

The Chatham Rise is located offshore of New Zealand's South Island. Vast areas of the Chatham Rise are covered in circular to elliptical seafloor depressions that appear to be forming through a bathymetrically controlled mechanism, as seafloor depressions 2-5 km in diameter are found in water depths of 800-1100 m. High resolution P-Cable 3D seismic data were acquired in 2013 across one of these depressions. The seafloor depression is interpreted as a mounded contourite. Our data reveal several smaller buried depressions (<20-650 m diameter) beneath the mounded contourite that we interpret as paleo-pockmarks. These pockmarks are underlain by a complex polygonal fault system that deforms strata and an unusual conical feature. We interpret the conical feature as a sediment remobilization structure based on the presence of stratified reflections within the feature, RMS amplitude values and lack of velocity anomaly that would indicate a non-sedimentary origin. The sediment remobilization structure, polygonal faults and paleo-depressions are indicators of past subsurface fluid flow. We hypothesize that the pockmarks provided the necessary topographic roughness for formation of the mounded contourites thus linking fluid expulsion and deposition of contouritic drifts.

Document Type: Article
Keywords: fluid flow, seafloor depressions, Chatham Rise, SO226
Research affiliation: OceanRep > GEOMAR > FB4 Dynamics of the Ocean Floor > FB4-GDY Marine Geodynamics
Refereed: Yes
Open Access Journal?: No
DOI etc.: 10.1111/bre.12237
ISSN: 0950-091X
Expeditions/Models/Experiments:
Date Deposited: 22 Jul 2016 08:59
Last Modified: 06 Apr 2017 08:14
URI: http://oceanrep.geomar.de/id/eprint/33448

Actions (login required)

View Item View Item

Document Downloads

More statistics for this item...