Manganese crust survey

Manganese crusts form a thin layer of mineral deposit that precipitates onto the surface of the seafloor at a rate of a few mm per million years. The crusts are thin, with thicknesses between 1 and 20cm, but have the potential to cover extremely vast regions of the seafloor, extending for several 10's of km. In this work, we aim to develop a way to survey the seafloor on these kinds of scales, by using a low flying underwater robot equipped with an acoustic sensor and a 3D visual mapping system to measure not only the distribution of the crusts on the seafloor, but also look beneath the seafloor and determine the thickness of the crusts.
To date, we have developed and deployed our measurement system at seamounts in the North west pacific and on the Phillipine sea plate.

          

Example of 3D reconstruction with overlaid acoustic thickness measurements

        

The ASV ABA (left) and the AUV "BOSS-A" being deployed for acoustic and 3D visual survey of Manganese crusts in the NW Pacific

Expeditions

2015

  • NT15-03 AUV acoustic survey and 3D mapping at #5 Takuyo seamount and Katayama seamount: Multivehicle operation using the AUV BOSS-A, the ASV ABA, the ROV Hyperdolphin and the R/V Natsushima, Chief Scientist: Blair Thornton, Jan. 2015

2013

  • NT13-13 Acoustic survey and 3D mapping at #5 Takuyo seamount using the ROV Hyperdolphin and the R/V Natsushima, Chief Scientist: Blair Thornton, June. 2013

≤2012

  • NT12-25 Acoustic survey and 3D mapping at Higashi Oki-daitou seamount using the ROV Hyperdolphin and the R/V Natsushima, Chief Scientist: Akira Usui, Sept. 2012
  • NT12-05 Acoustic survey and 3D mapping at #5 Takuyo seamount using the ROV Hyperdolphin and the R/V Natsushima, Chief Scientist: Blair Thornton, Feb. 2012
  • KY11-02 Leg2 3D mapping at Ryusei seamount using the ROV Hyperdolphin and the R/V Natsushima, Chief Scientist: Akira Usui, Feb. 2011
  • NT10-11 Acoustic survey and 3D mapping at #5 Takuyo seamount using the ROV Hyperdolphin and the R/V Natsushima, Chief Scientist: Blair Thornton, July 2010
  • KY10-04 3D mapping at Teisi knoll using the AUV/ROV Tuna sand and R/V Kaiyo, Chief Scientist: Tamaki Ura, March 2010
  • NT09-02Leg2 3D mapping at #5 Takuyo seamount using the ROV Hyperdolphin and the R/V Natsushima, Chief Scientist: Tetsuro Urabe, Feb. 2009

 


Latest

July 24, 2015
ACFR coming to IIS