TERRAPUB Journal of Oceanography

Journal of Oceanography, Vol. 64 (No. 3), pp. 471-477, 2008

Short Contribution

In-situ Survey of Nanomolar Manganese in Seawater Using an Autonomous Underwater Vehicle around a Volcanic Crater at Teishi Knoll, Sagami Bay, Japan

Takashi Doi1*, Michiaki Takano2, Kei Okamura3, Tamaki Ura4 and Toshitaka Gamo1

1Ocean Research Institute, The University of Tokyo, Nakano-ku, Tokyo 164-8639, Japan
2School of Environmental Science, The University of Shiga Prefecture, Hikone, Shiga 522-8533, Japan
3The Center for Advanced Marine Core Research, Kochi University, Nankoku, Kochi 783-8502, Japan
4Institute of Industrial Science, The University of Tokyo, Meguro-ku, Tokyo 153-8505, Japan

(Received 29 April 2007; in revised form 29 December 2007; accepted 4 January 2008)

Abstract: We present the results of a chemical survey at a submarine volcano, Teishi Knoll, obtained using a submersible in-situ Mn analyzer (GAMOS) mounted on an autonomous underwater vehicle (AUV) platform. During this survey, high-resolution data of dissolved Mn were obtained in three dimensions in nearly real time. The AUV enabled continuous detailed observations along a preprogrammed pathway, which could not have been performed with conventional CTD hydrocasts. During this observation, anomalously high dissolved Mn concentrations were obtained within the crater, corresponding to high water temperatures. The anomalies might be a hydrothermal signature due to volcanic activity from the crater.

*Corresponding author E-mail: takashidoi_1224@ybb.ne.jp

[Full text] (PDF 400 KB)