The rare-earth element (REE) geochemistry of sedimentary deposits has been used in provenance investigations despite the transformation that this group of elements may suffer during a depositional cycle. In the present investigation, we used the geochemistry and XRD mineralogy of a set of sand and mud fluvial deposits to evaluate the ability of REE parameters in provenance tracing, and the changes in REE geochemistry associated with weathering and sorting. The analyzed deposits were generated in a subtropical drainage basin where mafic and felsic units are evenly represented, and these crystalline rocks are covered by sedimentary successions in a wide portion of the basin. A few element ratios appear to hold robust information about primary sources (Eu/Y, Eu/Eu*, La_N/Yb_N, La_N/Sm_N, and Gd_N/Yb_N), and the provenance signal is best preserved in sand than in mud deposits. Sediment cycles, however, change the REE geochemistry, affecting mud and sand deposits differently. They are responsible for significant REE depletion through quartz dilution in sands and may promote discernible changes in REE patterns in muds (e.g., increase in Ce content and some light REE depletion relative to heavy REE).

Natural and anthropic hazards derived from climate change are endangering heritage and society. Geoheritage is vulnerable. Nowadays we are witnessing the destruction of monuments with high emotional significance due to wars, but climate change is also contributing to the loss of the same cultural heritage. Prevention is often the best way to protect geoheritage from disappearing and society is the best agent to implement preventive measures. Citizens are often unaware of the important treasures they have around them. Geoparks have been a great tool to bring awareness in society, since by involving the public in the whole process of recognition and promotion, they protect the space and the cultural and economic values associated with them. It is important to communicate the initiatives taking place in the geoparks to explain the importance of geology and the risk of losing the cultural value of these areas if natural hazards increase due to climate change, and also the risk to the population living in the area if those hazards reach destructive intensities. This paper is focused on discussing the case of Las Loras Geopark as an example to show the contribution of geoparks to the dissemination of science and the relevance of preserving geoheritage by implementing simple measures based on communication and prevention.