Laser-Induced Breakdown Spectroscopy Agronomical Application

An air-bone method of exploration of ore deposits has been realized with the help of luminescence Lidar. Lidar embodies high power UV laser and a coaxial telescope detection system installed aboard a helicopter. The laser yields pulses having peak power 0.4-0.5 mJ, time delay 1 ps, gate width 1 ms, repetition rate 30-50 Hz, wavelength varying from 275 up to 400 nm. The laser footprint is about 400-500 cm and the distance between the closest footprints about 1 m. Air-bone survey is carried out from an altitude of 50-75 m. Sensitivity is 0.2-0.5 % by exposed area for most of minerals (Seigel and Robbins 1982, 1985). 

AIS Sommer GmbH of Germany delivered laser-induced fluorescence (LIF) analyzer for quality control in minerals and mineral processing (Broicher 2000). The LIF analyzer includes two light detector systems with three photomultipliers each, which evaluate three spectral bands in two time windows each. It was done in Kiruna phosphorous iron ore mine, Sweden. The limitation of LIF analysis is that its accuracy depends on the complexity of the composition of the ore and the concentration and fluorescence properties of the critical minerals in relation to all the other minerals present. The phosphorous iron ore in Kiruna is ideal for LIF analyzes, because its iron minerals are practically non-luminescent, while magmatic apatite is strongly fluorescent with intensive emissions of Ce and Eu.  

2 Laser-Induced Breakdown Spectroscopy Agronomical Application 

LIBS demonstrated a great capacity for accurate analysis of samples of various compositions, even for in-situ sampling of soils that may exhibit surface dust accumulation. LIBS remote sensing capabilities also make this method an attractive option for a variety of soils analysis and agronomic applications. The ability to obtain immediate results from analyses allows for on-site evaluation of contaminants or pollutants, which can be particularly useful for environmental and 

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