RT Journal Article
T1 Seismic crustal structure in the southwest of the Iberian Peninsulaand the Gulf of Cadiz
A1 González Fernández, Antonio
A1 Córdoba Barba, Diego
A1 Vegas Martínez, Ramón
A1 Matías, Luis Manuel
AB The crust under the southwestern Iberian Peninsula and the Gulf of Cadiz has been sampled by 1200 km of deep seismicrefraction=wide-angle reflection profiles, together with many seismic reflection lines and bore-holes. Wide-angle seismicdata were collected during the last three decades. Commercial multichannel data provide a detailed image of the uppermostcrust, improving the confidence about the models of the deeper structures. P-wave velocities within the thick column ofsediments in the Gulf of Cadiz range from 2.0 to 3.8 km=s, while the Algarve and the Sines areas have higher velocitiesof 4.3 to 4.8 km=s. The top of the Palaeozoic basement rises to the northwest, outcropping in the South Portuguese zoneof the Iberian Massif, and is characterized by P-wave velocities of 5.7–5.9 km=s. High velocities of 6.4 km=s have beenfound at shallow depths of 7 to 10 km in the South Portuguese zone, that could be related to the mafic and ultramaficrocks in the Beja-Acebuches zone. Lower crustal velocities are in the range of 6.7–6.9 km=s. The crustal thickness showsimportant lateral changes from 29 km beneath the Guadalquivir Basin=Iberian Massif contact to 35 km in the southeasternpart of the South Portuguese zone. From the interpretation of these seismic data, a geodynamic model of the evolution ofthe crust in Southwestern Iberia and the Gulf of Cadiz is proposed. The Guadalquivir Basin, and its continuation at sea, theGulf of Cadiz, is a flexure area of the crust that could be related to the overloading due to the overthrusting of the AlboranDomain over the Iberian plate.
PB Elsevier, B.V.
SN 0040-1951
YR 1998
FD 1998
LK https://hdl.handle.net/20.500.14352/57606
UL https://hdl.handle.net/20.500.14352/57606
LA eng
DS Docta Complutense
RD 15 ago 2024