A new gravity survey (1164 gravity stations and 180 samples for density analysis) combined with two new geological cross sections has been carried out in a sector of the Central Pyrenees in order to improve the characterization of basement and cover architecture. From North to South, the study area comprises the southern half of the Axial Zone and the northernmost part of the South-Pyrenean Zone. New gravity data were combined with previous existing databases to obtain the Bouguer and residual anomaly maps of the study area. The two cross sections, oriented NNE–SSW, were built from field data and previous surficial and subsurface data and cross the La Maladeta plutonic complex. The residual anomaly map shows values ranging from −18 to 16 mGal and anomalies mainly oriented N120E. The two 2.5D modelled cross sections show similar observed gravity curves coinciding with similar interpreted structural architecture. Data show a gravity high oriented N120E coinciding with the Orri basement thrust sheet and an important gravity depression, with the same orientation, coinciding with the leading edge at depth of the Rialp basement thrust sheet and interpreted as linked to a large subsurface accumulation of Triassic evaporites. The volume at depth of the La Maladeta and Arties granites has been constrained through gravity modelling. This work highlights that the combination of structural geology and gravity modelling can help to determine the structural architecture of an orogen and localize accumulations of evaporites at depth.

The integration of geophysical modeling to classical structural studies constitutes a powerful approach to inferring the Earth's crust architecture (e.g.,

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Contractional deformation in the transition between the Iberian and Catalan Coastal Ranges (Linking Zone) generated both thin‐skinned structures detached in low‐strength Triassic units and basement‐involved structures. To evaluate their extent and relative contribution to the overall structure, we carried out a study combining structural geology and gravimetry. New gravity data (938 stations) and density determinations (827 samples) were acquired and combined with previous existing databases to obtain Bouguer anomaly and residual Bouguer anomaly maps of the study area. Seven serial and balanced cross sections were built, their depth geometries being constrained through the 2.5‐D gravity modeling and the 3‐D gravity inversion that we accomplished. The residual Bouguer anomaly map shows a good correlation between basement antiforms and gravity highs whereas negative anomalies mostly correspond to (i) Meso‐Cenozoic synclines and (ii) Neogene‐Quaternary basins. Cross sections depict a southern, thick‐skinned domain where extensional, basement faults inherited from Late Jurassic‐Early Cretaceous times were inverted during the Cenozoic. To the north, we interpret the existence of both Triassic‐detached and basement‐involved deformation domains. The two deformation styles are vertically overlapped in the southernmost part of the Catalan Coastal Ranges but relay both across and along strike in the Eastern Iberian Range. These basement and cover relationships and their along‐strike variations are analyzed in terms of the interplay between structural inheritance, its obliquity to the shortening direction, and the continuity and effectiveness of Triassic décollements in the study area.

We introduce the first map of density data in Northeastern Spain which can help in the interpretation of gravimetric surveying. The background map is a simplified version of the Geode continuous geological cartography (scale 1:200.000) of the Iberian Range and Ebro basin. These maps are synthetic and homogeneous maps based on previous 1:50,000 scale geological maps (MAGNA). The map uses the ETRS89 datum and UTM coordinates (30T northern zone) and covers an area of 140,000 sq km. The compiled data shown in the map come from previous papers of the region (≈ 700 points) as well as from more than 800 additional points developed in the course of an exploratory project focused on the underground characterization of a potential CO 2 reservoir in the so-called 'Linking Zone'. The new data accomplish some basic criteria; they are accurately georeferenced and lithology, stratigraphic age and other technical details about the measurements (e.g. means and error) and methods are fully displayed.