A view of a wind farm off the coast of Rudong county, Jiangsu province. XU CONGJUN/FOR CHINA DAILY

Offshore wind farms in Jiangsu province are playing a new role as seismic monitoring stations, significantly enhancing the region's maritime earthquake detection and early warning capabilities, according to provincial seismological bureau officials.

Since 2022, seismic monitoring devices have been installed on seven offshore wind farms in Jiangsu.

Along with three island-based seismic monitoring stations, these installations form the nation's first comprehensive maritime seismic monitoring network.

This innovative approach not only improves seismic data collection and analysis capabilities but also helps protect major offshore projects and the maritime industry, said Zheng Jiangrong, director of the Jiangsu Seismological Station.

Undersea earthquakes are a pressing issue in Jiangsu due to the complex geology of the seabed.

According to the bureau, 66 percent of earthquakes in the province occurred offshore. On Nov 17, 2021, a magnitude 5 earthquake struck the sea area off Dafeng district in Yancheng, highlighting the need for improving undersea earthquake monitoring.

Previously, a high-density seismic monitoring network was laid out within the land area of Jiangsu, but the stations at sea were sparse.

"Power supply, telecommunications and maintenance have been the major challenges for maritime seismic monitoring," Zheng said.

Gong Jie, senior engineer at the Jiangsu Seismological Station, said, in the past, seismic monitoring at sea relied on costly buoys and island-based stations. Buoys, deployed for months at a time, collected seismic data but could not transmit in real time. Island-based stations also struggled with stable power supply.

The 2021 Dafeng earthquake underscored the urgency for better maritime seismic monitoring, leading the bureau to collaborate with offshore wind power enterprises.

"Using offshore wind platforms for earthquake monitoring addresses many of the previous obstacles," Gong said.

Li Moting, an engineer with State Power Investment Corporation, one of the State-owned enterprises involved in the project, said seismic monitoring devices on offshore wind power platforms are powered by the wind turbines themselves, and data is transmitted in real time through existing submarine fiber optic cables.

"These devices require minimal power and are installed in easily accessible areas, significantly reducing costs compared with traditional monitoring methods," Li added.

"The cross-sector cooperation also highlights the potential of offshore wind farms to serve public and societal needs beyond power generation."

Zheng said that Jiangsu's success in transforming offshore wind farms into seismic monitoring stations serves as a model for other provinces grappling with maritime earthquake monitoring challenges.

Looking ahead, Jiangsu province plans to build two integrated maritime seismic observatories near the offshore wind platforms in Yancheng's Dafeng district.

The provincial seismological bureau also aims to apply artificial intelligence to enhance the quality of data collected from marine seismic monitoring.