**4. Conclusions**

The Las Loras UGGp present a high concentration of geological diversity components. The most part of them are associated to water circle shown a wide range of manifestations (springs, cave, canyons, travertine buildings, etc.) related to active processes whose action keep transforming the landscape.

The hydrogeological study carried out in this work show three types of sediments according to their behaviour: aquifers themselves, aquitards and aquifuges. An upper aquifer in the Las Loras UGGp includes materials between the Lower Cretaceous and the Quaternary. A deep regional aquifer is represented by marine Jurassic sediments. The first one, is characterized by aquifers with springs located above rivers. The deep regional aquifer is formed by confined aquifers.

Both aquifer systems do not show evidences of hydrogeological connection. The Lower Cretaceous materials acts as an aquitard that separates the upper from the deep aquifer. No signs of hydrothermalism have been recognized in the Ubierna Fault zone.

**Author Contributions:** Conceptualization, Á.d.l.H.-P.; methodology, Á.d.l.H.-P.; software, Á.d.l.H.-P.; validation, M.G., N.-E.L., M.C.-B., A.H.M., B.C., R.F., E.G.R., M.M.C.L., F.K.A.-G.; formal analysis, L.M.-M.; investigation, Á.d.l.H.-P., J.L.-G.; resources, M.G., J.Á.S.-F., K.S.; data curation, Á.d.l.H.-P.; writing—original draft preparation, Á.d.l.H.-P.; writing—review and editing, Á.d.l.H.-P., R.F.; visualization, Á.d.l.H.-P.; supervision, all co-authors; project administration, M.G.; funding acquisition, M.G., J.Á.S.-F., K.S. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research was funded by UNESCO International Geosciences Programme (IGCP) and by Severo Ochoa extraordinary grants for excellence IGME-CSIC (AECEX2021).

**Institutional Review Board Statement:** Not applicable.

**Informed Consent Statement:** Not applicable.

**Data Availability Statement:** Data supporting reported results can be found in Ref. [2].

**Acknowledgments:** The authors particularly thank the anonymous reviewer for the grea<sup>t</sup> contribution to the clarity and completeness of this paper.

**Conflicts of Interest:** The authors declare no conflict of interest.
