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The southern Central Andes (SCA) (between 27° S and 40° S) is bordered to the west by the convergent margin between the continental South American Plate and the oceanic Nazca Plate. The subduction angle along this margin is variable, as is the deformation of the upper plate. Between 33° S and 35° S, the subduction angle of the Nazca plate increases from sub-horizontal (< 5°) in the north to relatively steep (~ 30°) in the south. The SCA contain inherited lithological and structural heterogeneities within the crust that have been reactivated and overprinted since the onset of subduction and associated Cenozoic deformation within the Andean orogen. The distribution of the deformation within the SCA has often been attributed to the variations in the subduction angle and the reactivation of these inherited heterogeneities. However, the possible influence that the thickness and composition of the continental crust have had on both short-term and long-term deformation of the SCA is yet to be thoroughly investigated. For our investigations, we have derived density distributions and thicknesses for various layers that make up the lithosphere and evaluated their relationships with tectonic events that occurred over the history of the Andean orogeny and, in particular, investigated the short- and long-term nature of the present-day deformation processes. We established a 3D model of lithosphere beneath the orogen and its foreland (29° S–39° S) that is consistent with currently available geological and geophysical data, including the gravity data. The modelled crustal configuration and density distribution reveal spatial relationships with different tectonic domains: the crystalline crust in the orogen (the magmatic arc and the main orogenic wedge) is thicker (~ 55 km) and less dense (~ 2900 kg/m3) than in the forearc (~ 35 km, ~ 2975 kg/m3) and foreland (~ 30 km, ~ 3000 kg/m3). Crustal thickening in the orogen probably occurred as a result of stacking of low-density domains, while density and thickness variations beneath the forearc and foreland most likely reflect differences in the tectonic evolution of each area following crustal accretion. No clear spatial relationship exists between the density distribution within the lithosphere and previously proposed boundaries of crustal terranes accreted during the early Paleozoic. Areas with ongoing deformation show a spatial correlation with those areas that have the highest topographic gradients and where there are abrupt changes in the average crustal-density contrast. This suggests that the short-term deformation within the interior of the Andean orogen and its foreland is fundamentally influenced by the crustal composition and the relative thickness of different crustal layers. A thicker, denser, and potentially stronger lithosphere beneath the northern part of the SCA foreland is interpreted to have favoured a strong coupling between the Nazca and South American plates, facilitating the development of a sub-horizontal slab.

The North Patagonian Massif (NPM) area in Argentina includes a plateau of 1200 m a.s.l. (meters above sea level) average height, which is 500–700 m higher than its surrounding areas. The plateau shows no evidence of internal deformation, while the surrounding basins have been deformed during Cenozoic orogenic events. Previous works suggested that the plateau formation was caused by a lithospheric uplift event during the Paleogene. However, the causative processes responsible for the plateau origin and its current state remain speculative. To address some of these questions, we carried out 3D lithospheric-scale steady-state and transient thermal simulations of the NPM and its surroundings, as based on an existing 3D geological model of the area. Our results are indicative of a thicker and warmer lithosphere below the NPM plateau compared with its surroundings, suggesting that the plateau is still isostatically buoyant and thus explaining its present-day elevation. The transient thermal simulations agree with a heating event in the mantle during the Paleogene as the causative process leading to lithospheric uplift in the region and indicate that the thermo-mechanical effects of such an event would still be influencing the plateau evolution today. Although the elevation related to the heating would not be enough to reach the present plateau topography, we discuss other mechanisms, also connected with the mantle heating, that may have caused the observed relief. Lithosphere cooling in the plateau is ongoing, being delayed by the presence of a thick crust enriched in radiogenic minerals as compared to its sides, resulting in a thermal configuration that has yet to reach thermodynamic equilibrium.

We present a 3-D lithospheric-scale model covering the area of Germany that images the regional characteristics of the structural configuration and of the thermal field. The structural model resolves major sedimentary, crustal and lithospheric mantle units integrated from previous studies of the Central European Basin System, the Upper Rhine Graben and the Molasse Basin, together with published geological and geophysical data. A combined workflow consisting of 3-D structural, gravity and thermal modelling is applied to derive the 3-D thermal configuration. The modelled temperature distribution is highly variable in response to an imposed heterogeneous distribution of thermal properties assigned to the different units. First order variations in the temperature field are mainly attributed to the thermal blanketing effect from the sedimentary cover, the variability in the amount of radiogenic heat produced within the different crystalline crust compartments and the implemented topology of the thermal Lithosphere-Asthenosphere Boundary.

Plumes are domains where hotter material rises through Earth´s mantle, heating also the moving lithospheric plates that may experience thinning or even continental breakup. In particular, the Iceland plume in the NE Atlantic (NEA) could have been instrumental in facilitating the breakup between Europe and Laurentia in the earliest Eocene. Here we present an open access three-dimensional density model of the NEA crust and uppermost mantle that is consistent with previously un-integrated available data. We propose that high-density anomalies in the crust represent the preserved modifications of the lithosphere in consequence of the plate’s journey over the hot mantle plume. Besides, low-density anomalies in the uppermost mantle would represent the present-day effect of the mantle plume and its interaction with the mid-ocean ridges. Overall, the model indicates that the presence of the plume together with the pre-existing crustal configuration controlled the timing, mechanisms and localization of the NEA breakup.