A multi-channel chemical sensor and its application in detecting hydrothermal vents
There are well-established chemical and turbidity anomalies in the plumes occurring vicinity of hydrothermal vents, which are used to indicate their existence and locations. We here develop a small, accurate multi-channel chemical sensor to detect such anomalies which can be used in deep-sea at depths of more than 4 000 m. The design allowed five all-solid-state electrodes to be mounted on it and each (apart from one reference electrode) could be changed according to chemicals to be measured. Two experiments were conducted using the chemical sensors. The first was a shallow-sea trial which included sample measurements and in situ monitoring. pH, Eh, CO 3 2− and SO 4 2− electrodes were utilized to demonstrate that the chemical sensor was accurate and stable outside the laboratory. In the second experiment, the chemical sensor was integrated with pH, Eh, CO 3 2− and H2S electrodes, and was used in 29 scans of the seabed along the Southwest Indian Ridge (SWIR) to detect hydrothermal vents, from which 27 sets of valid data were obtained. Hydrothermal vents were identified by analyzing the chemical anomalies, the primary judging criteria were decreasing voltages of Eh and H2S, matched by increasing voltages of pH and CO 3 2− . We proposed that simultaneous detection of changes in these parameters will indicate a hydrothermal vent. Amongst the 27 valid sets of data, five potential hydrothermal vents were targeted using the proposed method. We suggest that our sensors could be widely employed by marine scientists.
Key wordschemical sensor multi-channel hydrothermal vents detection chemical anomalies SWIR
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- Banerjee R, Dick J B H, Wolfgang B. 2001. Discovery of peridotitehos-ted hydrothermal deposits along the ultraslow-spreading Southwest Indian Ridge. In: Geological Society of America annual meeting. Boston, 800Google Scholar
- Ding Qian, Pan Yiwen, Huang Yuanfeng, et al. 2015. The optimization of Ag/Ag2S electrode using carrier electroplating of nano silver particles and its preliminary application to offshore Kueishan Tao, Taiwan. Continental Shelf Research, 111: 262–267, doi: 10.1016/j.csr.2015.08.018CrossRefGoogle Scholar
- Fujimoto H. 1999. First submersible investigations of mid-ocean ridges in the Indian Ocean. Inter Ridge News, 8: 22–24Google Scholar
- Han Chenhua, Pan Yiwen, Ye Ying. 2009. CO2 microelectrode based on Zn-AI-LDH-ion carrier and its characterization. Journal of Tropical Oceanography (in Chinese), 28(4): 35–41Google Scholar
- Haymon R M, Fornari D J, Edwards M H, et al. 1991. Hydrothermal vent distribution along the East Pacific Rise crest (909′-54′ N) and its relationship to magmatic and tectonic processes on fast-spreading mid-ocean ridges. Earth and Planetary Science Letters, 104(2-4): 513–534, doi: 10.1016/0012-821X(91)90226-8CrossRefGoogle Scholar
- Provin C, Fukuba T, Okamura K, et al. 2013. An integrated microfluid-ic system for manganese anomaly detection based on chemilu-minescence: Description and practical use to discover hydro-thermal plumes near the Okinawa Trough. IEEE Journal of Oceanic Engineering, 38(1): 178–185, doi: 10.1109/JOE.2012.2208849CrossRefGoogle Scholar
- Wakita N, Hirokawa K, Ichikawa T, et al. 2010. Development of Autonomous Underwater Vehicle (AUV) for exploring deep sea marine mineral resources. Mitsubishi Heavy Industries Technical Review, 47(3): 73–80Google Scholar
- Walker S L, Baker E T, Resing J A, et al. 2007. A new tool for detecting hydrothermal plumes: An ORP Sensor for the PMEL MAPR. In: American Geophysical Union, Fall Meeting. Washington DC: American Geophysical UnionGoogle Scholar
- Ye Ying, Wu Daidai, Huang Xia, et al. 2003. Preparation and performance characterization of novel solid pH sensing electrodes. Journal of Transduction Technology (in Chinese), 16(4): 487–490Google Scholar