Examining monuments, shipwrecks or other artifacts such as statues or mosaics that have sunk into the sea is usually time-consuming and correspondingly expensive. In the EU project NERITES, European companies and research institutions from five countries therefore want to find a new way to better record the condition of underwater cultural heritage in the sea. The project partners want to develop a system for the remote measurement of chemical, ecological and geophysical indicators. This should work autonomously under water and thus reduce both the previously high costs and the risks for divers.

LZH develops compact LIBS system for depths of 100 meters

Scientists at the LZH in Hanover will contribute a compact system based on Laser Induced Breakdown Spectroscopy (LIBS) to the project. LIBS is a non-contact and virtually non-destructive method for analyzing chemical elements. It generates a laser-induced plasma that can be used to analyze solids as well as liquids and gases. The LZH can draw on the experience gained from the EU project ROBUST, in which a LIBS system was developed and successfully tested that can be used to examine samples in the deep sea at depths of up to 6,000 meters.

Measuring the concentration of metals

The LIBS system for the NERITES project should be able to measure whether and in what concentration metals such as iron, aluminum or zinc are present. The measurement will take place at a water depth of up to 100 meters and at a distance of around 20 centimetres. The scientists will use a green 532 nanometer double-pulse laser and a line scanner.

A platform that combines several measurement technologies

The partners also involved in the NERITES project are supplementing the system with additional measurement technologies: a quantum cascade laser sensor will map hydrocarbons and carbonates, while image measurement systems will provide information on textures and colors. Together, they should provide a comprehensive overview of the condition of the underwater artifacts. The aim is to integrate the measuring systems on a single transportable platform. This is supplied with power from an energy and data docking station and can therefore work and communicate autonomously.

Protecting underwater cultural assets

Coastal and marine regions harbour a rich but hidden cultural diversity that represents an important body of knowledge for human civilization. This heritage is endangered by anthropogenic and natural influences. Although some countries have already introduced legal protection measures, the monitoring and preservation of underwater archaeological sites remains a challenge. Improving monitoring technologies and further developing approaches to assess conditions and impacts are crucial for sustainable conservation.

Funded by the EU

The project "Systematic autonomous remote surveying of underwater cultural heritage monuments and artefacts using non-destructive, cost-effective and transportable platform" (NERITES) is therefore also funded by the EU under the call HORIZON-CL2-2023-HERITAGE-01 of the Horizon Europe funding program. Further information can be found on the project website at https://nerites.eu

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