Rapid growth of mineral deposits at artificial seafloor hydrothermal vents

• DOI: 10.1038/srep22163
• Publication Date: 2016-02-25T10:22:44Z
• Authors: Tatsuo Nozaki; Jun-Ichiro Ishibashi; Kazuhiko Shimada; Toshiro Nagase; Yutaro Takaya; Yasuhiro Kato; Shinsuke Kawagucci; Tomoo Watsuji; Takazo Shibuya; Ryoichi Yamada; Tomokazu Saruhashi; Masanori Kyo; Ken Takai
• Keywords: Seafloor Spreading; Deposition; Chimney (locomotive)

Abstract Seafloor massive sulphide deposits are potential resources for base and precious metals (Cu-Pb-Zn ± Ag Au), but difficulties in estimating precise reserves assessing environmental impacts hinder exploration commercial mining. Here, we report petrological geochemical properties of chimneys less than 2 years old that formed where scientific boreholes vented hydrothermal fluids the Iheya-North field, Okinawa Trough, East China Sea. One these infant chimneys, dominated by Cu-Pb-Zn-rich minerals, grew a height 15 m within 25 months. Portions sulphate minerals. Some sulphide-rich similar to high-grade Cu-Pb-Zn bodies on land, albeit with relatively low As Sb concentrations. The high growth rate reaching months is attributed large vent more 50 cm diameter created borehole, which induced slow mixing ambient seawater enhanced efficiency deposition. These observations suggest possibility cultivating seafloor even controlling their grades through manipulations how mix quench seawater.