FOUNDATIONS OF THE FUTURE: 3D GEOLOGICAL MODELLING FOR SUSTAINABLE CITIES

We have reached a key milestone in history where the majority of the world’s population now lives in urban areas. The urban subsurface is increasingly being seen as a resource to place infrastructure and habitation, as well as a source of drinking water and green energy. The natural and artificially modified deposits and rocks under cities provide both opportunities and constraints which mediate/regulate our interactions with the subsurface. With such competing demands it is critical that cities maximise the economic, social and environmental benefits of their subsurface resources while also safeguarding them for the future.

Urban 3D geological modelling is an important tool for managing and de-risking the urban subsurface. Geological models allow a range of characteristics of subsurface environments to be predicted and simulated, aiding the mitigation of geohazards, management of groundwater resources, and development of infrastructure. However, for effective applications at the urban-scale, high-resolution 3D characterisation of geological systems and integration of non-geological data (such as buried assets, land uses, and nature of building foundations) and knowledge are required. Furthermore, urban 3D modelling also requires predicting deposits that are not often shown on traditional Geological Survey maps such as human-made ground and sub-formational heterogeneity.

Using case studies, we explore the advances, benefits, and challenges of shallow subsurface, urban-scale 3D modelling in the UK context. We highlight applications for predicting and characterising natural and human-made ground to identify potential ground hazards and to protect archaeological deposits, and the use of 3D modelling to support a new underground observatory for understanding resource sustainability and the subsurface environmental impacts of mine water geothermal heating. We will also show how models can be used to understand how different hazards can interact with each other in the subsurface.