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A review of the S‐velocity structure beneath South America, for the crust and upper mantle, is performed using a recent methodology based on Rayleigh wave analysis, and a new 3D S‐velocity model (from 0 to 400 km depth) is achieved for this study area. The precise location and structure of the asthenosphere have been both determined from this new model, which have not been obtained in other previous studies, allowing to know how the different geological units that compose South America are delimited in terms of S‐velocity and lithosphere thickness. For example, the highest S‐velocities and the thickest lithosphere of the cratonic areas, are determined at the east of the Amazonian Craton and the São Francisco Craton. The lithosphere beneath the Guyana Shield is thinner than beneath the Central Brazil Shield, and the lithospheric root of the Amazonian Craton is determined deeper than the São Francisco Craton. The lithosphere at the east of the Central Brazil Shield is the thickest (~200‐km thick). Another interesting feature depicted in terms of S‐velocity and lithosphere thickness is the Transbrasiliano Lineament, which is determined in the crust and the upper mantle, confirming that it is not just a surface feature but a deep feature. [ABSTRACT FROM AUTHOR]

The article "CO2 polar mass on Mars determined from InSight pressure data" published in Frontiers in Astronomy & Space Sciences discusses the determination of the total mass of CO2 exchanged between the Martian atmosphere and surface using pressure data from the InSight mission. The study compares the results with data from gamma ray and neutron measurements and predictions from general circulation models. The findings suggest that pressure data can accurately determine the total mass of CO2 involved in the cycle, highlighting the impact of dust storms on Martian meteorology and the need for further research in this area. [Extracted from the article]

The elastic structure beneath the Gulf of Mexico and the Caribbean Sea is presented in this paper by means of S‐velocity maps, for depths ranging from 0 to 350 km, determined from Rayleigh‐wave analysis. The S‐velocity mapping, for the depth range from 0 to 5 km, shows clearly the distribution of sedimentary basins of the study area. For the depth range from 5 to 35 km, the higher S‐velocity values are associated to the areas in which the crust is thinner (oceanic crust). For the Caribbean Plate, which consists of the Venezuelan and Colombian basins separated by the Beata Ridge, a differentiation between both basins is possible in terms of S‐velocity. The thickening of the Caribbean crust (observed in the southern part of the study area), due to the Caribbean–South America plate interactions, is confirmed by the S‐velocity mapping; thickened crust is characterized by S‐velocities lower than those for the upper mantle. For depths greater than 35 km, the S‐velocity presents its higher values at the older regions of the study area, while the younger or active regions are imaged with low S‐velocity. Finally, a new and very interesting feature presented in this study is the location and thickness of the lithosphere–asthenosphere system. On the other hand, this study provides the mapping necessary to locate the deep geologic structures, present in the study area, which tectonic and geologic evolution is wished to determine, allowing also to know the nature and type of the crust and upper‐mantle structure beneath this area. Once this knowledge is reached, an evolutionary model can be developed. This study is especially interesting for areas in the Gulf of Mexico that are hidden beneath near‐opaque, complex, and extensive allochthonous salt bodies, which make it difficult to use other seismic exploration techniques such as seismic refraction or reflection techniques. [ABSTRACT FROM AUTHOR]