The OGS takes part in an international expedition to explore submerged aquifers off the New England Coast
Beneath the seabed, deposits of fresh and brackish water are sometimes found, trapped within underground aquifers whose origins and dynamics remain largely unexplored. To shed light on these concealed ecosystems, the self-elevating jackup rig Robert departed on 19 May from the port of Bridgeport, USA. The rig serves as the operational base for the international IODP³-NSF Expedition 501 “New England Shelf Hydrogeology”, promoted by the International Ocean Drilling Programme (IODP³) and the United States National Science Foundation (NSF).
The OGS is also partaking in this expedition, which is diveded into two phases (offshore and onshore operations) and involves 41 scientists from 13 different countries. Among those participating in the mission is Cristina Corradin, an OGS researcher currently engaged in the RESCUE project, who will be a member of the Shore-based Science Team.
Cristina Corradin will collaborate as part of the OGS hydrogeology group to develop a geostatistical model mapping the distribution of sedimentary facies and subsequently produce a hydrogeological model of the study area. This will be based on both newly acquired and pre-existing data, alongside pumping tests conducted onboard. These models will allow simulation of groundwater circulation to evaluate the potential active recharge from the continent towards the ocean, the origin of offshore freshwaters, and the mechanisms behind their emplacement and migration.
The Robert jackup rig will drill into the seabed to depths of up to 550 metres below the ocean floor. Water and sediment samples will be collected from up to three carefully selected sites, with the data gathered expected to shed light on whether these offshore aquifers date back to glacial periods—when sea levels were considerably lower—or stem from other as yet unknown processes.
By contributing to the study of a hidden and potentially strategic water resource, the OGS once again affirms its pivotal role in international geoscientific research.