Return to search

EROSION OF SEAFLOOR RIDGES AT THE TOP OF THE GAS HYDRATE STABILITY ZONE, HIKURANGI MARGIN, NEW ZEALAND – NEW INSIGHTS FROM RESEARCH CRUISES BETWEEN 2005 AND 2007.

It was proposed that erosion of subsea ridges on the Hikurangi margin may be linked to a
fluctuating level of the top of gas hydrate stability in the ocean. Since publication of this
hypothesis, three field campaigns were conducted in the study area. Here we summarize relevant
results from these cruises. We found that water temperature fluctuations occur at lower
frequencies and higher amplitudes than previously thought, making it more likely that
temperature changes reach sub-seafloor gas hydrates. Dredge samples encountered numerous
consolidated mudstones. We speculate that gas hydrate “freeze-thaw” cycles may lead to dilation
of fractures in mudstones due to capillary forces, weakening the seafloor. Ubiquitous gas pockets
beneath the ridge may lead to overpressure that may also contribute to seafloor fracturing.

Identiferoai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:BVAU.2429/1551
Date07 1900
CreatorsPecher, Ingo A., Henrys, Stuart A., Ellis, Susan, Crutchley, Gareth, Fohrmann, Miko, Gorman, Andrew R., Greinert, Jens, Chiswell, Stephen M., TAN0607 Scientific Party, SO191 Scientific Party
Source SetsLibrary and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada
LanguageEnglish
Detected LanguageEnglish
Typetext
RightsPecher, Ingo A.

Page generated in 0.0017 seconds