Combining laser-induced breakdown spectroscopy (LIBS) and time-gated Raman spectroscopy for underwater ores...

Area of Science:

• Geochemistry
• Spectroscopy
• Marine Geology

Background:

• Depleting land-based mineral resources necessitate exploration of deep-sea metal deposits.
• Traditional ore analysis methods are time-consuming and lack real-time feedback.
• In-situ, rapid underwater ore identification is crucial for efficient deep-sea mining.

Purpose of the Study:

• To develop a rapid, in-situ technique for underwater ore identification.
• To integrate laser-induced breakdown spectroscopy (LIBS) and time-gated Raman spectroscopy.
• To evaluate data fusion strategies for improved ore classification.

Main Methods:

• An integrated LIBS-Raman setup was designed using a single laser and spectrometer.
• Ore samples were analyzed in deionized water.
• Partial least squares discriminant analysis (PLS-DA) was employed for classification.
• Data-level and feature-level fusion strategies were implemented.

Main Results:

• The integrated LIBS-Raman system achieved high accuracy in underwater ore identification.
• Data fusion significantly improved classification compared to individual methods.
• Data-level fusion yielded a 99.11% accuracy, while feature-level fusion achieved 98.44% with reduced computation.
• Successive projections algorithm (SPA) enhanced feature-level model efficiency.

Conclusions:

• LIBS and Raman spectroscopy are effective for rapid underwater ore identification.
• The integrated setup is suitable for developing compact, low-power deep-sea mining devices.
• This technology supports efficient and real-time feedback for deep-sea exploration.