Story by Erin Heffron

The ECSPB Marianas Survey Team in front of survey vessel, the M/V FUGRO SUPPORTER, at the Port of Saipan. From left: Giuseppe Masetti, Michael Smith, Erin Heffron, Tiziana Munene, and Andy Armstrong.

From September 14th through October 13th, two CCOM/JHC researchers and three graduate students participated in a cruise aboard the M/V Fugro Supporter. On board were Giuseppe Masetti, Research Assistant Professor; Michael Smith, Master’s Student, Ocean Engineering—Ocean Mapping; Erin Heffron, Master’s Student, Earth Sciences—Ocean Mapping; Tiziana Munene, Master’s Student, Ocean Engineering—Ocean Mapping; and Andy Armstrong, Co-Director Joint Hydrographic Center and Chief Scientist for this cruise. The purpose of the survey was to collect multibeam bathymetry, backscatter, and water-column data, as well as high-resolution subbottom profile data in the region surrounding the Northern Mariana Islands. This data was being collected as part of the Center’s Extended Continental Shelf Bathymetry Project. The data collected will be used to support the U.S. Extended Continental Shelf Project.

The Mariana Archipelago is in the North Pacific (see image below). The Northern Mariana Islands (Commonwealth of the Northern Mariana Islands, CNMI) is a U.S. commonwealth and includes all of the islands in the island arc except Guam, which is a separate U.S. territory. For this cruise, we will be departing from the island of Saipan. Saipan is a volcanic island (inactive), with fringing coral reefs, caves, and incredible scenery. It was also the site of the WWII Battle of Saipan and hosts many historic sites and parks memorializing soldiers, sailors, and airmen of various nationalities that fought and died there.

Left, location of the Mariana Archipelago. Right, the location of Guam and Saipan within the island arc. Images created in Google Earth.

This was the fifth cruise to the Mariana in support of the UNCLOS Bathymetry Project, following on efforts in 2006, 2007, and 2010. The bathymetry data coverage from previous cruises is shown below. The total area of these surveys is almost 495,000 km². On this cruise, the team surveyed in the north, covering portions of the trench and arc-ridge complex, as well as the Parece Vela Basin (see image below).

Mapping results from 2006, 2007, and 2010. Depths are in meters; the color legend pertains to the mapping results only, and is not indicative of the depths in the background map. Image created using QPS Fledermaus software.

Regional map showing all available multibeam bathymetry from a variety of agencies and countries, with major geological features labeled (Image 5). The white lines are the planned survey lines for this cruise. Depths are in meters and correspond to the multibeam bathymetry data only. Image created using QPS Fledermaus software.