Optical interferometry-based array of seafloor environmental sensors using a transoceanic submarine cable

Area of Science:

• Geophysics
• Oceanography
• Fiber Optic Sensing

Background:

• Existing undersea fiber optic communication cables offer vast potential for Earth observation.
• Previous sensing methods were limited to integrated measurements over entire cable lengths.
• The deep ocean floor remains largely unmonitored by permanent, real-time sensors.

Purpose of the Study:

• To demonstrate localized environmental sensing using existing submarine communication cable infrastructure.
• To detect seismic and oceanic events on individual spans between cable repeaters.
• To enable widespread, real-time seafloor monitoring without infrastructure modification.

Main Methods:

• Utilized optical fiber-based sensing technology.
• Applied techniques to a 5860-kilometer transatlantic communication cable.
• Focused on detecting signals within individual repeater spans (45-90 km).

Main Results:

• Successfully detected earthquakes and ocean signals on individual cable spans.
• Demonstrated sensing capabilities over specific segments, not just the entire cable length.
• Validated the feasibility of using existing infrastructure for localized measurements.

Conclusions:

• Optical fiber sensing can be applied to existing submarine cables for localized seafloor event detection.
• This method allows for the creation of a dense network of real-time ocean sensors.
• The approach requires no modifications to the existing undersea communication network, offering a cost-effective solution for ocean monitoring.