CHARACTERIZATION OF ATMOSPHERIC DUST AT GURUSHIKAR, MT ABU, RAJASTHAN

The nature of atmospheric aerosols at Gurushikar, Mt. Abu, Rajasthan w here a gamma ray telescope is to be installed, was investigated. Air p articulate samples collected on filters were used to estimate the tota l suspended particulate matter (TSPM) and its elemental composition. T he TSPM varied from 31 to 103 mu g/m(3) during January to March 1994. The heighest loads were observed during the months of May and June (80 -100 mu g/m(3)) and lowest during October (20-60 mu g/m(3)). The dust was also examined for size, shape and nature of the mineral matter. Th e particle sizes varied from 100 mu m to 5 mu m. The course particles (>50 mu m) are irregular shaped quartz grains. Some of the medium size (=50 mu m) particles were spherical and were highly conducting. These particles were rich in iron content. Correlation coefficients among v arious elements in the dust showed that it is made up of mainly two co mponents - wind blown ground dust and particulate arising out of wood and coal burning.