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[EN] The tectonic map at scale 1:1,750,000 presented in this work shows an update of the existing knowledge of the main tectonic and volcanic structures along the Iberian continental margins and abyssal plains. The morphotectonic trends around Iberia recorded superposed geodynamic processes linked to the opening of the North Atlantic Ocean since the Mesozoic and the evolution of the Mediterranean Sea during the Cenozoic, as well as the reactivation of Hercynian faults and the formation of new tectonic structures during the Alpine orogeny. This map is based on the interpretation of the digital bathymetric model and other geophysical data from our own studies, and those from other authors. The morphotectonic features in this map provides a basis for the recognition of the tectonic control at lithospheric plate scale and the establishment of potential tectonic and volcanic risk zones.

The Drake Passage is an oceanic gateway of about 850 km width located between South America and the Antarctic Peninsula that connects the southeastern Pacific Ocean with the southwestern Atlantic Ocean. It is an important gateway for mantle flow, oceanographic water masses, and migrations of biota. This sector developed within the framework of the geodynamic evolution of the Scotia Arc, including continental fragmentation processes and oceanic crust creation, since the oblique divergence of the South American plate to the north and the Antarctic plate to the south started in the Eocene. As a consequence of its complex tectonic evolution and subsequent submarine processes, as sedimentary infill and erosion mainly controlled by bottom currents and active tectonics, this region shows a varied physiography. We present a detailed map of the bathymetry and geological setting of the Drake Passage that is mainly founded on a new compilation of precise multibeam bathymetric data obtained on 120 cruises between 1992 and 2015, resulting in a new Digital Bathymetric Model with 200 × 200 m cell spacing. The map covers an area of 1,465,000 km2 between parallels 52°S and 63°S and meridians 70°W and 50°W at scale 1:1,600,000 allowing the identification of the main seafloor features. In addition, the map includes useful geological information related to magnetism, seismicity and tectonics. This work constitutes an international cooperative effort and is part of the International Bathymetric Chart of the Southern Ocean project, under the Scientific Committee on Antarctic Research umbrella. © 2018, © 2018 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group on behalf of Journal of Map.

The NW Iberian continental margin has a complex structure, resulting from the succession of several rifting episodes close to a ridge triple junction, and a superimposed partial tectonic inversion stage. The wide-ranging physiography matches the diverse tectonic deformation domains related to its evolution. Each deformation domain has a distinctive gravity signal, so the detailed Bouguer anomaly map presented here is a good first approach to the regional study of the whole margin. Moreover, as the presented chart is a complete Bouguer anomaly map (including terrain corrections), its analysis and interpretation can be done in terms of density, geometry and depth variations below the seafloor. This map is mainly based on the dataset obtained during seven one-month surveys carried out in the frame of the Spanish Economic Exclusive Zone project, and also includes two 2¿+¿3/4D density models illustrating the deep structure of the margin.

The acoustic facies analyses have provided an important basis for sedimentary processes in the deep-sea environments. The echo-character mapping, through the interpretation and correlation of very high-resolution seismic profiles, is a very useful tool for the characterization of the recent sedimentary processes and their distribution. This work presents the first echo-character map at 1:800,000 scale of the Galicia Continental Margin and the adjacent abyssal plains elaborated by the Geological Survey of Spain. The map was carried out on the basis of the analysis and interpretation of the bathymetry and reflectivity data from the SIMRAD EM12, EM120 and EM1002 echosounders, and the high-resolution seismic profiles from the SIMRAD TOPAS PS18 parametric echosounder. On the basis of seafloor morphology, surface bedforms, backscatter and sub-bottom acoustic echocharacters, 26 echo-types were identified in the uppermost sedimentary sequence. These echo-types have been grouped into four main echoes: Distinct, Irregular, Hyperbolic and Undulated, according to their main acoustic characteristics. This information has been acquired in the framework of the ‘Scientific Research Program of the Economic Exclusive Zone of Spain’, which is coordinated and leaded by the Defense Ministry of Spain, during the oceanographic cruises carried out on board of the R/V Hesperides in 2001–2003 and 2006–2009.

Bouguer anomaly maps are powerful cartographic tools used mainly by geoscientists and natural resources’ companies (oil, mining, etc.) since they reflect rock density distribution at different depths, allowing the identification of different tectonic features. At upper crustal levels, Bouguer anomaly maps can help, for instance, in characterizing possible ore deposits, ground water reservoirs, petroleum resources, CO2 storage sites and sedimentary basins; at deeper crustal levels they can help to further refine seismic velocity models or other integrated geophysical models and thus help in deciphering the lateral density variations within the crust and the geometry of the base of the crust. This new Bouguer anomaly map at a 1:1,500,000 scale is based on the compilation of 210,283 gravity stations covering the Iberian Peninsula (c. 583,254 km2). The new map upgrades previous maps in two ways: (1) it is built up from a database with a 15% more spatial coverage than previous compilations and (2) it is freely available. This map show shorter wavelengths than previous published maps thus allowing investigation of smaller geological features.

Bouguer anomaly maps are powerful cartographic tools used mainly by geoscientists and natural resources’ companies (oil, mining, etc.) since they reflect rock density distribution at different depths, allowing the identification of different tectonic features. At upper crustal levels, Bouguer anomaly maps can help, for instance, in characterizing possible ore deposits, ground water reservoirs, petroleum resources, CO2 storage sites and sedimentary basins; at deeper crustal levels they can help to further refine seismic velocity models or other integrated geophysical models and thus help in deciphering the lateral density variations within the crust and the geometry of the base of the crust. This new Bouguer anomaly map at a 1:1,500,000 scale is based on the compilation of 210,283 gravity stations covering the Iberian Peninsula (c. 583,254 km2). The new map upgrades previous maps in two ways: (1) it is built up from a database with a 15% more spatial coverage than previous compilations and (2) it is freely available. This map show shorter wavelengths than previous published maps thus allowing investigation of smaller geological features.

RADARSAT-2 data in the ultra-fine and fine quad polarization mode was evaluated to identify morpho-structural, periglacial, and other geomorphological features within the Antarctic Peninsula region. The study was carried out within Byers Peninsula, the largest ice-free area on the South Shetland Islands. A methodology was developed to integrate and compare data from different sources to optimize the selection of criteria and techniques to obtain information from RADARSAT-2 relevant to the geomorphology of the study area. Ultra-fine data were focused on the extraction of linear features and fine structures; whereas, fine quad polarized data were implemented to identify scattering mechanisms for different surface covers. It was possible to extract a greater number of lineaments and structures with the ultra-fine data. A supervised classification was carried out using the fine quad polarized data, where a careful selection of training and validation sites was needed. The overall classification accuracy was 75% with a Kappa coefficient of 0.71. Surface cover features with low entropy scattering mechanisms were well identified with a maximum of 86% accuracy. The accuracy for higher entropy volume and multiple scattering mechanisms were only slightly lower and are considered especially important for the type of geomorphological features studied on Byers Peninsula

RADARSAT-2 data in the ultra-fine and fine quad polarization mode was evaluated to identify morpho-structural, periglacial, and other geomorphological features within the Antarctic Peninsula region. The study was carried out within Byers Peninsula, the largest ice-free area on the South Shetland Islands. A methodology was developed to integrate and compare data from different sources to optimize the selection of criteria and techniques to obtain information from RADARSAT-2 relevant to the geomorphology of the study area. Ultra-fine data were focused on the extraction of linear features and fine structures; whereas, fine quad polarized data were implemented to identify scattering mechanisms for different surface covers. It was possible to extract a greater number of lineaments and structures with the ultra-fine data. A supervised classification was carried out using the fine quad polarized data, where a careful selection of training and validation sites was needed. The overall classification accuracy was 75% with a Kappa coefficient of 0.71. Surface cover features with low entropy scattering mechanisms were well identified with a maximum of 86% accuracy. The accuracy for higher entropy volume and multiple scattering mechanisms were only slightly lower and are considered especially important for the type of geomorphological features studied on Byers Peninsula