Geotechnical study in Castilléjar

In Castilléjar, soils formed by gypsum, anhydrite and salts predominate, accounting for a significant proportion beneath the surface. The presence of compact gravels and sands, together with materials such as sandstones and conglomerates, indicates locally good conditions for supporting moderate loads, although the risk of dissolution associated with the gypsum and salts requires particular attention, as it may affect the stability of the foundation. The low occurrence of clays and hard marls suggests a reduced likelihood of differential settlements, but the high gypsum contents require a detailed geotechnical study before defining the most suitable type of foundation.

Seismicity in Castilléjar is very low, with five recorded events over thirty years and a maximum magnitude of 3.4, which implies a low level of seismic hazard for structural design. The presence of non-clayey bedrock eliminates the risk of clay expansivity. However, the main geotechnical constraint arises from the possible existence of karst processes and dissolution-related hazards associated with the gypsum, anhydrite and salts; therefore, it is essential to verify the presence of voids and the ground’s stability before establishing any foundation.