Mantle wedge hydration in Nicaragua from Local Earthquake Tomography.

Dinc-Akdogan, Nilay, Rabbel, Wolfgang, Flueh, Ernst R. and Taylor, W. (2011) Mantle wedge hydration in Nicaragua from Local Earthquake Tomography. Geophysical Journal International, 186 (1). pp. 92-112. DOI 10.1111/j.1365-246X.2011.05041.x.

[img] Text
Dinc.pdf - Published Version
Restricted to Registered users only

Download (1536Kb) | Contact

Supplementary data:

Abstract

The continental margin of Nicaragua and Costa Rica is characterized by significant lateral changes from north to south such as a decreasing dip of the slab, a decreasing magma production and a shift in the volcanic front. To investigate this transition, a joint on- and offshore local earthquake tomography was performed. Low P-wave velocities and high Vp/Vs ratios, indicative for hydration, were found in the upper-mantle and lowermost crust beneath the Sandino Basin. The mantle wedge hydration can be estimated to 2.5 wt. per cent beneath south Nicaragua. In contrast, the mantle wedge beneath north Costa Rica is weakly or not hydrated. The hydration leads to a local gap in the seismicity in Nicaragua. The lateral transition between the hydrated and non-hydrated areas occurs within a distance of about 10 km. This transition coincides with a change in the crustal thickness in the order of 5–10 km, thickening to the south, and in the tectonic regimes. The change in the tectonic regimes towards a stronger extension along the margin of Nicaragua could be the key for understanding the observations: the extension may support the opening of pathways for a wide zone of fluid migration and hydration through the overriding plate which are identified with areas of low Vp, high Vp/Vs and low seismicity.

Document Type: Article
Keywords: Seismology; Geophysics; Hydrothermal systems; Seismic tomography; Subduction zone processes; Continental margins: convergent
Research affiliation: Kiel University > Faculty of Mathematics and Natural Sciences > Institute of Geosciences
OceanRep > SFB 574
OceanRep > SFB 574 > A2
OceanRep > GEOMAR > FB4 Dynamics of the Ocean Floor > FB4-GDY Marine Geodynamics
Kiel University
OceanRep > The Future Ocean - Cluster of Excellence
Refereed: Yes
Open Access Journal?: No
DOI etc.: 10.1111/j.1365-246X.2011.05041.x
ISSN: 0956-540X
Projects: Future Ocean
Contribution Number:
ProjectNumber
SFB 574154
Expeditions/Models/Experiments:
Date Deposited: 13 Jul 2010 11:00
Last Modified: 10 Oct 2012 07:35
URI: http://oceanrep.geomar.de/id/eprint/8628

Actions (login required)

View Item View Item

Document Downloads

More statistics for this item...