de Franco, R.

Grevemeyer, Ingo

Guzman, M.

Möller, Stefan

Prada, M.

Ranero, César R.

Sallarés, V.

Zitellini, N.

English

OceanRep

Geophysical Research AbstractsVol. 14, EGU2012-13065, 2012EGU General Assembly 2012© Author(s) 2012Rifting of the Tyrrhenian Basin, a complex interaction among faulting ,magmatism and mantle exhumation.C. R. Ranero (1), V. Sallarés (2), I. Grevemeyer (3), N. Zitellini (4), M. Guzman (5), M. Prada (2), S. Moeller (3),R. de Franco (6), and T h e MEDOC Cruise Party ()(1) Barcelona Center for Subsurface Imaging, ICREA at CSIC, ICM-CSIC, , Barcelona, Spain (cranero@icm.csic.es,+34-(0)93-2309555), (2) Barcelona Center for Subsurface Imaging, UTM-CSIC, Barcelona, Spain, (3) GEOMAR | HelmholtzCentre of Ocean Research, Kiel, Germany, (4) ISMAR. CNR. Via Gobetti 101 - 40129 - Bologna – Italy, (5) Barcelona Centerfor Subsurface Imaging, ICM-CSIC, , Barcelona, Spain (cranero@icm.csic.es, +34-(0)93-2309555), (6) IDPA. CNR, Milan,ItalyThe Tyrrhenian basin has been created during the extension of continental lithosphere driven by the retreat of aIonian slab across the mantle. The basin does not seem to be actively extending, but its preserved crustal structureprovides information of the time evolution of the processes involved in rifting. The basin rifted from north tosouth, with rifting stopping after progressively larger stretching factor towards the south. The northern regionstopped opening after a relatively low extension factor. Towards the south extension increased up to full crustalseparation that produced mantle exhumation. The final structure displays two conjugate margins with asymmetricstructures. Thus, the basin provides a natural laboratory to investigate a full rift system, that displays variableamounts of extension.We present observations from a two-ship seismic experiment that took place in spring 2010. The cruise took placeon two legs. In the first leg, the Spanish R/V Sarmiento de Gamboa and the Italian R/V Urania collected five E-Wtrending wide-angle seismic (WAS) profiles across the entire basin using 17 Ocean Bottom Seismometers and 25Ocean Bottom Hydrophones and a 4800 c.i. G-II gun array. The profiles were extended with land stations thatrecorded the marine shots. During a second leg the R/V Sarmiento de Gamboa collected 16 Multichannel SeismicReflection (MCS) profiles using a 3.75 km-long streamer and a 3000 c.i. G-II gun array. MCS profiles wereacquired coincident with the WAS profiles, and a number of additional lines concentrated in the central region ofthe basin where mantle exhumation took place. The seismic profiles were located to cover regions of the basin thatdisplays different amount of extension, and the coincident wide-angle and MCS transects cross the entire basin toimage the two conjugate margins.In this presentation we compare observations from different transects mapping the structures produced at differentextension factors. A comparison of the different transects permits to trade space (different transects mappingdifferent extension factors) for time (different transects provide an evolutionary snapshot of the extension process).Each transect provides the tectonic structure, the geometry of sedimentary deposits, and P-wave seismic velocitydistribution. This information allows to interpret the mechanisms of deformation, infer the importance andpotential role of magmatism in the rifting process, and estimate the region of mantle exhumation, currentlyinferred from one drill site. The analysis of the data provides insight in the process of formation of asymmetrystructure conjugated margins.

Rifting of the Tyrrhenian Basin, a complex interaction among faulting , magmatism and mantle exhumation

Rifting of the Tyrrhenian Basin, a complex interaction among faulting , magmatism and mantle exhumation

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