open access

https://hdl.handle.net/2115/44892

WHATS : a new multi-bottle gas-tight sampler for sea-floor vent fluids

日本語

handling pressured sample

2003-08-01

日本地球化学会

Chikyukagaku (Geochemistry)

37(3)

101-109

We report a newly developed water sampler WHATS (Water and Hydrothermal-fluid Atsuryoku Tight Sampler), for collecting seafloor venting gas-rich fluid (or gas itself) at in situ pressure (Atsuryoku means pressure in Japanese). It consist of four 150 cm3 stainless steel sample cylinders, eight ball valves, a motor-driven arm, a rail, a peristaltic pump, and a flexible Teflon tube connected to a titanium inlet tube. The motor-driven arm on the rail can open one of the four cylinders. Then, by pumping out pure water that has filled the cylinder, we can introduce sample fluid into the cylinder. After completely replacing the pure water with sample fluid, the valves at both ends of the cylinder are tightly closed by moving the motor-driven arm again. At this stage, the next cylinder becomes to be ready for next sampling. We can take maximum 4 different gas-tight samples in series. Whole operation can be arranged inside the submersible cabin. Use of only one motor to operate valves makes the sampler small, light (28 kg in water), and easy to handle. With the sampler, we can collect almost uncontaminated sample because we pump fluid slowly (120 cm3/min.) into the cylinder using the peristaltic pump. To date, the sampler has been used for ca. 40 dives of shinkai 2000 and shinkai 6500 with the success rate of more the 90%. We also evaluate the safety factors in handling highly pressured samples. We conclude that the sampler can be used to the depth of 3,000 m.

学術雑誌論文

Version of Record

0386-4073

AN00141280