Construction of a 3D geological model to reduce the vulnerability of groundwater resources to climate change: the case of Gran Canaria (Canary Islands, Spain)

Climate change poses a major challenge to sustainable groundwater management, especially in island territories. In this context, the development of innovative tools for characterising aquifers is essential to reduce their vulnerability. Currently, 3D geological modelling allows the geometric properties of geological bodies to be defined, making it possible to infer their structure, volumes and determine the availability of their groundwater resources. These three-dimensional models also form the basis for implementing numerical flow simulations, providing valuable geoscientific information for the proper management of aquifers.

Within the framework of the GENESIS project, this work presents the first 3D geological model of the volcanic island of Gran Canaria (Canary Islands, Spain). The 3D model was created using GeoModeller software, based on the island's Digital Terrain Model, surface geological maps, geological cross-sections and lithological data from boreholes and wells. The geological model obtained covers the entire surface of the island of Gran Canaria and includes a geological sequence of six main formations representing the most important volcanic edifices and geological and hydrogeological structures on the island, including the Caldera Tejeda, the remains of the Roque Nublo stratovolcano and the island's characteristic radial ravine system.

The 3D geological model will serve as the basis for the development of the first hydrogeological model of the island of Gran Canaria. This new information will be key to improving knowledge about the island's aquifer and implementing nature-based solutions (NbS), creating new management strategies to tackle climate change.