|MVSEIS – Tectonic control, deep crustal structure and fluid escape pathways in the Gulf of Cadiz Mud volcano field|
Luis Menezes Pinheiro
Programme - PDCTM
Execution dates - 2003-07-01 - 2008-12-31 (66 Months)
Funding Entity - FCT (parte nacional)
Funding for CESAM - 723513 €
Proponent Institution - Universidade de Aveiro
This project investigates the deep crustal structure, the sedimentary section and sediment dynamics, the tectonic control and the detailed geometry of the fluid escape pathways in the Gulf of Cadiz. A multiscale approach to the imaging of the mud volcanic edifices, fluid conduits and largescale tectonic control on gas escape features, based on multichannel seismic profiles, single channel seismics and closely spaced high resolution 2-D seismic surveys. Particular attention is put into unravelling the links between the deep faulting in the accretionary complex/olistostrome and the mud volcanism. The transition between focused flow and diffuse flow patterns in shallow horizons, the intrinsic facies of the diffuse flow pathways and the role of stratigraphic controls on flow deflection and shallow migration pathways is also be investigated, as well as the relative role of climate-controlled oceanographic variability versus tectonics in the episodic formation and activity of fluid venting structures. Particular emphasis is put into unravelling the effect of the periodic variability of the Mediterranean Outflow Water (MOW) on the dissociation of gas hydrates, particularly in the northern sector of the Gulf of Cadiz, and the contribution of the release of the methane stored in the oceanic sediments to the formation of carbonate crusts and chimneys and to the greenhouse gas effect. Using heat-flow data and high resolution bathymetry, attempts are made to locally estimate the areal extent of some areas of gas hydrates and gas seepage in the Gulf of Cadiz.