Geotechnical study in Cizur

In Cizur, soils are predominantly formed by limestones, dolomites and marbles, which usually provide a high bearing capacity, making them favourable for shallow foundations where the geomorphological conditions allow it. In addition, levels of sandstones, conglomerates, flysch, and loose materials such as fine sands and silts are found occasionally, whereas compacted gravels and sands appear rarely. 5.37% of the soils correspond to gypsum, anhydrite and salts, which introduces the risk of dissolution and differential settlements—an essential variable for the design and execution of foundations.

Local seismicity is classified as moderate, with a record of 27 seismic events in the last 30 years and a maximum magnitude of 4.2; therefore, the geotechnical study must incorporate this consideration into the structural calculations. The substratum, with no dominant clay components, rules out risks associated with expansivity. However, the potential presence of karst phenomena in the limestone mass requires thorough prior verification before any foundation, since the existence of voids or cavities can decisively condition the stability of structures in the area.