Development of an Easy-to-Operate Underwater Raman System for Deep-Sea Cold Seep and Hydrothermal Vent In Situ Detection

As a powerful in situ detection technique, Raman spectroscopy is becoming a popular underwater investigation method, especially in deep-sea research. In this paper, an easy-to-operate underwater Raman system with a compact design and competitive sensitivity is introduced. All the components, including the optical module and the electronic module, were packaged in an L362 × Φ172 mm titanium capsule with a weight of 20 kg in the air (about 12 kg in water). By optimising the laser coupling mode and focusing lens parameters, a competitive sensitivity was achieved with the detection limit of SO42- being 0.7 mmol/L. The first sea trial was carried out with the aid of a 3000 m grade remotely operated vehicle (ROV) "FCV3000" in October 2018. Over 20,000 spectra were captured from the targets interested, including methane hydrate, clamshell in the area of cold seep, and bacterial mats around a hydrothermal vent, with a maximum depth of 1038 m. A Raman peak at 2592 cm-1 was found in the methane hydrate spectra, which revealed the presence of hydrogen sulfide in the seeping gas. In addition, we also found sulfur in the bacterial mats, confirming the involvement of micro-organisms in the sulfur cycle in the hydrothermal field. It is expected that the system can be developed as a universal deep-sea survey and detection equipment in the near future.

Medienart:

E-Artikel

Erscheinungsjahr:

2021

Erschienen:

2021

Enthalten in:

Zur Gesamtaufnahme - volume:21

Enthalten in:

Sensors (Basel, Switzerland) - 21(2021), 15 vom: 27. Juli

Sprache:

Englisch

Beteiligte Personen:

Liu, Qingsheng [VerfasserIn]
Guo, Jinjia [VerfasserIn]
Ye, Wangquan [VerfasserIn]
Cheng, Kai [VerfasserIn]
Qi, Fujun [VerfasserIn]
Zheng, Ronger [VerfasserIn]
Sun, Zhilei [VerfasserIn]
Zhang, Xilin [VerfasserIn]

Links:

Volltext

Themen:

Cold seep
Deep sea
Hydrothermal vent
In situ detection
Journal Article
Methane
OP0UW79H66
Raman system

Anmerkungen:

Date Completed 11.08.2021

Date Revised 13.08.2021

published: Electronic

Citation Status MEDLINE

doi:

10.3390/s21155090

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM329164376