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The Gorringe Bank is a 5000 m high seamount near the Atlantic coast of Iberia characterized by a 9 m high geoid anomaly and a ~ 120 reGal Bouguer anomaly relative to the surrounding abyssal plains. It has been linked to a NW directed thrust carrying exhumed upper mantle rocks and transitional crust on top of flexed-down Eurasian oceanic crust along the Tagus Abyssal Plain. However, estimations of crustal shortening have yielded dissimilar results, and the deep structure of the ridge remains highly unknown. We present a restored cross section and a new model of the lithospheric structure based on gravity, geoid, elevation, and the presence of serpentinized peridotites. At least 20 km of shortening took place along a flat-ramp-flat thrust fault, and the density structure of the lithosphere is consistent with mantle serpentinization varying from 70% at the surface to 20% at 14 km depth and 0% at 40 km. The topographic relief and gravity anomalies are explained by assuming a flexural isostatic model with an elastic thickness [T.sub.e] of ~30 km. The evolution of the Gorringe Bank since the Late Jurassic is interpreted in relation to Eurasia-Africa-North America plate motion in four stages: (1) transtension between Newfoundland-Iberia and Africa, which generated small oceanic basins and mantle exhumation; (2) opening of the North Atlantic and seafloor spreading at the NW side of the exhumed Gorringe, which produced gabbro intrusions and serpentinization; (3) a quiescent tectonic period dominated by subsidence and sediment accumulation; and (4) a transpressional plate boundary between Eurasia and Africa with NW directed subcrustal thrusting and generation of the present Gorringe relief. doi: 10.1029/2009TC002458.

[1] We perform numerical modeling to investigate the mechanisms leading to the postcollisional tectonic evolution of the Alps. We model the lithospheric deformation as a viscous thin sheet with vertically averaged rheology and coupled with surface mass transport. The applied kinematic boundary conditions simulate the convergence between the Adria indenter and the European foreland during the last 35 Myr. Model predictions of elevation, lithospheric structure, erosion/sedimentation pattern and vertical axis rotation are compared with observations of the planform shape of the chain, topography, crustal thickness, distribution of rock exhumation and sediment thickness, and paleomagnetic rotations. Thickening of the lithosphere in the Alpine region is shown to be highly sensitive to the assumed viscosity law, to the strength contrasts between the different regions and to the surface mass transport. Modeling results indicate that the large-scale deformation of the Alps during the postcollisional phase is mainly controlled by accommodation of convergence in a weak orogenic zone caught between a nearly rigid Adria plate and a strong European foreland. Modeling of the present-day stress field shows that (1) the present rotation of Adria is responsible for the change of extension direction from strike-perpendicular in the western Alps to strike-parallel in the east and (2) the strike-perpendicular extension observed in the western Alps is likely due to lateral variations of gravitational potential energy. The results suggest a NNE shift of about 700 km of the Euler pole of Adria relative to Europe from its mean position during postcollisional deformation to the present day. doi: 10.1029/2004TC001754.

[1] We analyze the Cenozoic topographic evolution of the Catalan Coastal Ranges (NE Spain) and the role of fault activity, erosion, sedimentation, and isostasy in controlling uplift and subsidence. A forward numerical model constrained by an extensive geological and geophysical data set is used to examine the temporal and spatial record of Cenozoic vertical motions. We show that the effect of isostasy, erosion, and sedimentation is as important as the contribution of fault deformation to the topography of the Catalan Coastal Ranges. The model predicts that Paleogene topography generation by thrusting was compensated by erosion (up to 1.3 km) and isostatic subsidence (up to 1.2 km), resulting in a 1.2-1.9 km high mountain range by the end of compression (29 Ma). During the Neogene, strong tectonic subsidence related to normal faulting and the consequent flexural uplift (of 0.7-1.2 km), surface erosion (as much as 1.6-2.3 km), and sedimentation (up to 4.5 km) led to the present landscape configuration. Extension rates along the Barcelona fault controlled flexural uplift and, in combination with erosion and sedimentation processes, led to the migration of the topographic maximum of the Prelitoral Range toward the easternmost Ebro Basin. INDEX TERMS: 8105 Tectonophysics: Continental margins and sedimentary basins (1212); 8015 Structural Geology: Local crustal structure; 3210 Mathematical Geophysics: Modeling; 8109 Tectonophysics: Continental tectonics--extensional (0905); KEYWORDS: modeling, vertical motions, NE Spain. Citation: Gaspar-Escribano, J. M., D. Garcia-Castellanos, E. Roca, and S. Cloetingh (2004), Cenozoic verticaI motions of the Catalan Coastal Ranges (NE Spain): The role of tectonics, isostasy, and surface transport.

[1] Integration of stress indicator data, gravity data, crustal kinematics data, and analysis of topography and recent vertical motions demonstrates the occurrence of consistently oriented spatial patterns of large-scale Alpine to recent intraplate deformation in Iberia. The inferred upper crustal and lithospheric deformation patterns and the timing of the associated expressions at or near the surface support the existence of a close coupling with plate boundary processes operating at the margins of Iberia. Patterns of lithosphere and upper crustal folds are oriented perpendicular to the main axis of present-day intraplate compression in Iberia inferred from structural analysis of stress indicator data and focal mechanism solutions. These findings suggest the presence of lithospheric folds, with wavelengths compatible with theoretical predictions of folding wavelengths of Variscan lithosphere. Stress-induced intraplate deformation set up by plate interactions is compatible with indications for the absence of present-day deep mantle-lithosphere interactions inferred from seismic tomography. INDEX TERMS: 8105 Tectonophysics: Continental margins and sedimentary basins; 8107 Tectonophysics: Continental neotectonics; 8122 Tectonophysics: Dynamics, gravity and tectonics; 8159 Tectonophysics: Evolution of the Earth Rheology--crust and lithosphere; 8164 Tectonophysics: Evolution of the Earth Stresses--crust and lithosphere; KEYWORDS: lithospheric folding, intraplate deformation, Iberia, recent vertical motions, drainage patterns. Citation: Cloetingh, S., E. Burov, F. Beekman, B. Andeweg, P. A. M. Andriessen, D. Garcia-Castellanos, G. de Vicente, and R. Vegas, Lithospheric folding in Iberia, Tectonics, 21(5), 1041, doi: 10.1029/2001TC901031, 2002. Received 31 July 2001; revised 27 December 2001; accepted 15 January 2002; published 4 October 2002.

[1] Previous quantitative studies dealing with the origin of foreland basins have focused primarily either on the rheological basis of the lithosphere mechanical response or on the relationship between orogenic loading and sediment geometry. To link the evolution of the Guadalquivir foreland basin (South Iberia) with the thermomechanical stratification of the Iberian lithosphere, we combine quantitative approaches to deep and shallow processes: thrust loading, lithospheric flexure, thickness changes of the crust and the lithospheric mantle, and surface mass transport. A planform flexural analysis of the presentday load distribution shows that basement subsidence is related not only to upper crustal thrusting but also to a deep-seated additional load. On the basis of the observed gravity and geoid fields, we propose this additional load to be related to a lithospheric mantle thickening larger than the coeval crustal thickening. Further modeling of the evolution of a basin cross section reveals that the architecture of the sedimentary basin is additionally related to the lithosphere rheological response. The quantitative study of the evolution of basement faulting and the forebulge uplift of Sierra Morena leads us to conclude that viscous stress relaxation and/or plastic yielding within the lithosphere are key processes to explain the flexural evolution of the basin. INDEX TERMS: 8105 Tectonophysics: Continental margins and sedimentary basins; 8102 Tectonophysics: Continental contractional orogenic belts; 8120 Tectonophysics: Dynamics of lithosphere and mantle--general; 8122 Tectonophysics: Dynamics, gravity and tectonics; 8158 Tectonophysics: Evolution of the Earth: Plate motions--present and recent (3040); KEYWORDS: lithospheric flexure, anelastic rheology, basin architecture, hidden load, Betic Range, Sierra Morena