MERMAIDS - Floating seismographs

What are Mermaids?

Developed by engineers from OSEAN in close collaboration with scientists from the the Université de la Côte d'Azur (formerly the University of Nice/Sophia Antipolis) and Princeton, Mermaids are the first instruments capable of seismometry in quasi-real time in the oceans.

How do they work?

The Mermaid can dive down to depths as large as 3000 m by using a pump and an oil reservoir to reduce its volume. It has a hydrophone that picks up acoustic signals from earthquakes, essentially seismograms of compressional (P) waves. Whenever the onboard computer recognizes a strong earthquake signal, the float comes to the surface and transmits the data via satellite (Iridium) and takes its position from GPS. In addition to the hydrophone, the Mermaid measures the ocean temperature during its descent, and can be equipped with a CTD to measure salinity as well. The Mermaid trajectories are used by oceanographers to monitor abyssal currents.

EarthScope Oceans

Easy to launch, even from recreational vessels, and not requiring extensive engineering support such as needed for ocean bottom seismometers, Mermaids are crucial for systematic monitoring of the oceans, which will start with seismological and oceanographic monitoring in 2017, and will be extended in 2019 to cover monitoring of whales and dolphins, rainfall, and the ocean's chemistry. The South University of Science and Technology of China in Shenzhen takes the lead in this project that has been named EarthScope Oceans. The Mermaid Data Portal will move to SUSTech by the end of 2017.

The Mermaid development was made possible with financial support from the European Research Council.

EarthScope is a trademark of the Incorporated Research Institutions for Seismology (IRIS), and EarthScope-Oceans is not affiliated with NSF's EarthScope project.