Several projects involving the exploitation of the seabed have become or are becoming a reality: the operation of port areas and waterways; dredging and dumping operations in maritime areas; offshore wind farms; pumped-storage hydroelectric plants; gas pipelines and communication cables; the permanent connection between Saaremaa and the mainland; the Tallinn–Helsinki tunnel; offshore fish, algae, and shellfish farms.
Geological mapping of the seabed
The planning and utilisation of maritime areas requires a geological mapping of the seabed to be carried out. This will also involve the preparation of an overview of the mineral resources located in the waters, as well as a geological assessment of the options for exploiting them.
One of the tasks of the Geological Survey of Estonia (EGT) is to manage the collected and processed information and make it accessible to the public. The EGT is able to do this thanks to both its modern equipment and experience in the geological exploration of the seabed.
Sea coastal surveys and monitoring
The monitoring of sea coasts has been conducted as part of the national environmental monitoring activities since 1994. The purpose of the monitoring is to track coastal processes (erosion and deposition) driven by natural and anthropogenic factors and to explain their development trends. Monitoring operations involve ascertaining the potential development of various coastal areas (necessary for the construction of ports, buildings, and roads, as well as the planning of recreational infrastructure) and providing a development forecast for the whole of the coast.
The results obtained, data collected, and thematic maps prepared in the course of monitoring operations are submitted to the Estonian Environment Agency via the national environmental monitoring database KESE.
Surveys of the environmental status of seabed sediments
Seabed and coastal surveys are highly important for reaching a good environmental status for the Baltic Sea, as well as for understanding how the environmental status of the Baltic Sea has changed over time, and for predicting possible future scenarios. In order to know how potential changes (e.g., population growth, infrastructure developments, intensification of transport, climate change, etc.) will affect the overall ecological status of the Baltic Sea in the future, it is crucial to assess the ecological changes that have already occurred in the Baltic Sea and to plan mitigation measures where necessary.
Marine geological survey capacities of the EGT
For the mapping of shallow maritime waters, the EGT has a research vessel that is equipped with seismoacoustic (Pinger-, Chirp-, and Boomer-type) profilers and sonar systems with different operating frequencies, which allow us to study the topography of the seabed as well as the cross-section of the Quaternary cover. The data obtained with this equipment makes it possible to create map layers and 3D models of various geological units (moraine and bedrock surface, Quaternary cover thickness, etc.). For the determination of the composition of sediments, the EGT collects bottom samples with a Van Veen grab sampler or Gemax corer.
