Mapping the Clarion-Clipperton Fracture Zone

Map of transits

After two successful expeditions in the Hawaiian Archipelago--exploring from volcanic seamounts and recent lava flows off Hawaii’s Big Island to the outer reaches of Papahānaumokuākea Marine National Monument--E/V Nautilus is heading back to the mainland! While in transit from Honolulu to San Francisco, as Nautilus’ operations move back to the US West Coast, the team will conduct targeted seafloor mapping of a couple special regions. E/V Nautilus is equipped with a multibeam sonar and sub-bottom echosounder to collect bathymetric, surface sediment characteristic, subsurface geology and water column data.

The initial phase of the transit has been planned to transit southeast from Honolulu to map a section in the Clarion Clipperton Fracture Zone that is adjacent to areas designated for seabed mining under the International Seabed Authority (ISA). The ISA regulates deep seabed mining and also ensures that the marine environment is protected from any harmful effects that may arise during mining activities, including exploration. One of the areas identified for seabed mining of polymetallic modules is the Clarion-Clipperton Fracture Zone, but there is limited information and data related to the habitat in the CCFZ primarily because of the remoteness of the region. The team will maximize the value of the short time available while in transit to the mainland to ensure the mapping of this region adds to, and complements, available data to support future ROV exploration and other planned scientific cruises in the area.

Sea toad
Ocean Exploration Trust
A sea toad rests atop manganese nodules

The remainder of the transit route back to the US West Coast is planned to utilize the multibeam echosounder and sub-bottom profiler to fill in gaps in seabed mapping coverage across the Pacific. The routes planned will aim at mapping areas of the ocean that have never been explored, and the mapping data will be publically available and also be contributed to the Seabed 2030 project, an international collaborative project aiming to bring together all available bathymetric data to produce the definitive map of the world ocean floor by 2030.

Drop cam
Ocean Exploration Trust

During this transit, the Nautilus team is also collaborating with the National Geographic Society (NGS), which is providing two dropcams for use during the transit. The Deep Ocean Dropcam was developed by National Geographic Exploration Technology Lab as an efficient way to capture video of the sea floor. It is a high definition camera encased in a pressure housing rated to go to the deepest part of the ocean, with onboard lights to illuminate the scene. The camera is weighted and free falls to the sea floor, where it is programmed to record for a number of hours; when done recording, the burnwire connecting it to the weight dissolves, and it freely floats to the surface for recovery.