Keywords: atmospheric, influx, quartz, aeolian, laser counter, pollution, PSA.

Aeolian derived from the arid and semi-arid regions of the globe is an important component of Earth's tropospheric aerosol burden. While the Sahara is the single largest global source, deserts of the North American continent are also a significant source of airborne inputs in the northern hemisphere. The estimation of deposition of atmospheric influx in high-elevation areas in the western United States is problematic because all components of the deposition (e.g., rain, snow, cloudwater, dryfall, and gases) have seldom been measured concurrently [5,6].

Moreover, the scale at which human activity alters the natural environment has increased dramatically in the last three centuries. As a consequence total population and per capita resource use began to grow exponentially, though not at the same rate everywhere. Total material flow from the resource base, through the human economy and back into the environment as waste, has multiplied many times over and is threatening the environmental systems upon which life on Earth depends.

The extent and the magnitude of atmospheric influx into a mountainous area located in the North of Arizona State was tested using a chemically resistance compound (quartz SiO2). Two criteria methods were selected in this experiment: Particle size analysis using laser counter for size range between 1-100 m, and Mathematical treatment of size distribution to determine if the samples came from the same depositional environment. Cumulative percentages of the quartz size distribution data were used using the computational technique of the moment statistics [2]. The descriptive statistics used are mean size, standard deviation, skewness, and kurtosis (a measure that has no visual analogy) is used with skewness to compare sample sorting and source.

The quartz content was determined as a function of particle size of soils over quartz free basaltic tephra in Arizona. Soils from Greens Peak Apache County, Arizona showed a decrease of quartz content from the east side to the west side and on average from the north to the south side of the peak. The contents of quartz was higher in the surface horizons than in the lower horizons. Quartz particle size distribution in these soils is dominantly in the range of 10-50 m. It is suggested that the quartz was added as loess sized material of mainly local origin brought into profiles by eolian transport.

The particle size analysis (mass based) showed skewness values close to zero, kurtosis values less than three, and standard deviation less than one. Moreover, all sites showed similar average for the mean, standard deviation, skewness, and kurtosis . The great resemblance in the size distribution proved by the four moment statistical analysis indicates that these inputs were well sorted and came from the same source [3]. In addition to that, the presence of significant amounts of quartz from quartz-free basalt and basaltic tephra provides an excellent marker to form the basis to evaluate atmospheric contamination or inputs.

Recognizing the source of atmospheric contamination using simple method (compared to isotope technology) is valuable input to pollution science. The next step in this research will be examining how much pollutants are found in each size separates. This step will enable us to determine the amount, source of different pollutants and the behavior of different type of pollutants.

1

Aubele, J.C., T.S. Crumpler, M. Shafiqullah. "K-Ar ages of late Cenozoic rocks of the central and Eastern parts of the Springerville volcanic field, East-Cenral Arizona". J. Sochron west. 46: 3-5, 1986.

2

Griffiths, J.C. "Scientific methods of analysis of sediments". McGraw-Hill. Book Company. New York, 1967.

3

Trask, P.D. "Origin and environment of source sediments of petroleum". Houston, Gulf Publication Co., 67 pp, 1932.

4

Mizota, C. "Tropospheric origin of quartz in and soils in the red-yellow soils on basalts", Japan. Soil Sci. Plant Nutr. 28(4): 517-522, 1982.

5

Prospero, J.M., Charlson, R.J., Mohnen, V., Jaenicke, R., Delany, A.C., Moyers, J., Zoller, W., Rahn, K. "The atmospheric aerosol system: an overview". J. Geophys. Res. 21, 1607-1629, 1983. doi:10.1029/RG021i007p01607

6

Prospero, J.M. "Mineral-aerosol transport to the north Atlantic and north pacific: the impact of African and Asian sources". In: The long-range atmospheric, 1990.

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