S U M M A R YThe simulated annealing method was applied to jointly invert gravity and resistivity data to obtain the geometry of the density/resistivity interfaces and subsurface electrical resistivity distribution. The results obtained from the inversions of synthetic data indicate that the joint inversion significantly improves the solution decreasing the ambiguity of the models. The method was applied to gravity and resistivity data carried out in Sinai (northwestern Egypt). The results obtained revealed the geometry of the water-bearing zone with thickness ranging from 80 to 180 m and of the limestone-bedrock interface dipping northwards.

The 250 × 20-70 km Iberian Pyrite Belt (IPB) is a Variscan metallogenic province in SW Portugal and Spain hosting the largest concentration of massive sulphide deposits worldwide. The lowermost stratigraphic unit is the early Givetian to late Famennian-Strunian (base unknown) PhylliteQuartzite Group (PQG), with shales, quartz-sandstones, quartzwacke siltstones, minor conglomerate and limestones at the top. The PQG is overlain by the Volcanic Sedimentary Complex (VSC), of late Famennian to mid-late Visean age, with a lower part of mafic volcanic rocks, rhyolites, dacites and dark shales, hosting VHMS deposits on top (many times capped by a jasper/chert layer), and an upper part, with dark, purple and other shales and volcanogenic/volcaniclastic rocks, carrying Mn oxide deposits. The VSC is covered by the thousands of meters thick Baixo Alentejo Flysch Group of late Visean to Moscovian age. The VSC

The combined effects of post-rift magma emplacement and tectonic inversion on the hyper-extended West Iberian Margin are unravelled in detail using multichannel 2D/3D seismic data. The Estremadura Spur, acting as an uplifted crustal block bounded by two first-order transfer zones, shows evidence of four post-rift tectonic

SUMMARY We propose a 3‐D gravity model for the volcanic structure of the island of Maio (Cape Verde archipelago) with the objective of solving some open questions concerning the geometry and depth of the intrusive Central Igneous Complex. A gravity survey was made covering almost the entire surface of the island. The gravity data was inverted through a non‐linear 3‐D approach which provided a model constructed in a random growth process. The residual Bouguer gravity field shows a single positive anomaly presenting an elliptic shape with a NW–SE trending long axis. This Bouguer gravity anomaly is slightly off‐centred with the island but its outline is concordant with the surface exposure of the Central Igneous Complex. The gravimetric modelling shows a high‐density volume whose centre of mass is about 4500 m deep. With increasing depth, and despite the restricted gravimetric resolution, the horizontal sections of the model suggest the presence of two distinct bodies, whose relative position accounts for the elongated shape of the high positive Bouguer gravity anomaly. These bodies are interpreted as magma chambers whose coeval volcanic counterparts are no longer preserved. The orientation defined by the two bodies is similar to that of other structures known in the southern group of the Cape Verde islands, thus suggesting a possible structural control constraining the location of the plutonic intrusions.

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