Schmidt Ocean Institute’s R/V Falkor conducted high-resolution undersea mapping in collaboration with NASA, as a mission of opportunity in conjunction with the Vent Life Expedition exploring ecosystem dynamics of the hydrothermal vent fields in the nearby eastern Lau Basin. This survey contributes to the project to extend satellite-based measurements that NASA’s Earth Sciences Program began in summer of 2015 with collaborators from the National Geospatial-Intelligence Agency (NGA) and the Canadian Space Agency (via their Radarsat-2 satellite), as well as the German Space Agency (DLR).
Since much of the landscape dynamics associated with new oceanic island volcanoes happens underwater, this unique project of opportunity provides scientists at NASA and Columbia’s Lamont-Doherty Earth Observatory with an integrated view of the three-dimensional character of the new island from the seafloor to its approximately 130 meters tall summit above sea-level, all at spectacular meter-scale resolution.
(3D model of the new island)
This topographic viewpoint will serve to better understand how such rapidly-formed volcanic islands evolve and why their long-term survival as land is often so limited and short in duration. It will also contribute to an understanding of hydro-volcanic processes on planets such as Mars where similar-appearing volcanic structures (i.e., to the new island in Tonga, shown in the figure below) have been observed by NASA satellites such as the Mars Reconnaissance Orbiter (MRO).
R/V Falkor has excellent high-resolution mapping capabilities and has recently discovered several new underwater features such as the recently named Falkor Seamount. Falkor’s bathymetric mapping capabilities were able to be rapidly deployed to map a large region of complex seafloor topography around the new island, which is unofficially called Hunga Tonga Hunga Ha’apai (HTHH) on the basis of nearby pre-existing islands in the Kingdom of Tonga. Preliminary analysis by Columbia University scientist Dr. Vicki Ferrini, together with NASA scientists from the Goddard Space Flight Center, has showcased why the new island has lost nearly 30 percent of its initial land area in only 15 months since the eruptive activity ended in late January 2015. Just as at Goddard Space Flight Center, has showcased why the new island has lost nearly 30 percent of its initial land area in only 15 months since the eruptive activity ended in late January 2015. Just as at Surtsey island in the North Atlantic Ocean (near Iceland), the submarine topography around HTHH clearly exerts a controlling effect on the pace and location of erosion due primarily to marine abrasion and local subsidence.