Lithospheric structure in Central Eurasia derived from elevation, geoid anomaly and thermal analysis

<p>We present new crustal and lithospheric thickness maps for Central Eurasia from the combination of elevation and geoid anomaly data and thermal analysis. The results are strongly constrained by numerous previous data based on seismological and seismic experiments, tomographic imaging and integrated geophysical studies. Our results indicate that high topography regions are associated with crustal thickening that is at a maximum below the Zagros, Himalaya, Tien Shan and the Tibetan Plateau. The stiffer continental blocks that remain undeformed within the continental collision areas are characterized by a slightly thickened crust and flat topography. Lithospheric thickness and crustal thickness show different patterns that highlight an important strain partitioning within the lithosphere. The Arabia–Eurasia collision zone is characterized by a thick lithosphere underneath the Zagros belt, whereas a thin to non-existent lithospheric mantle is observed beneath the Iranian and Anatolian plateaus. Conversely, the India–Eurasia collision zone is characterized by a very thick lithosphere below its southern part as a consequence of the underplating of the cold and stiff Indian lithosphere. Our new model presents great improvements compared to previous global models available for the region, and allows us to discuss major aspects related to the lithospheric structure and acting geodynamic processes in Central Eurasia. </p

Updated Bouguer anomalies of the Iberian Peninsula: a new perspective to interpret the regional geology

<p>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.</p