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This paper considers the distribution of technogenic 137Cs and naturally occurring radionuclides:238U,232Th and 40K concentrations in soils and 137Cs in atmospheric dry depositions by altitudinal belts of the Aragats mountain massif,Republic of Armenia.Undisturbed soil samples were collected at altitudes from 1000 to 3200 m.For the determination of geochemical variability,two soil sampling campaigns were undertaken.Atmospheric dry depositions were sampled from five stations at 1100-3200 m collected onto organic fiber filters between June and December 2016.137Cs activity was measured using a high-purity Germanium detector coupled to a multichannel analyzer (Canberra).Results indicated th`t specific activity of 137Cs in soils at 1000m is 495-528 Bq m-2,and at 3200 m is 10,500-11,470 Bq m-2.No correlation observed for 137Cs versus naturally occurring radionuclides,which varies in distribution by altitude.Specific activities of 137Cs in dry atmospheric depositions varies from 1.06 at 846 m to 2.37 Bq m-2 per quarter at 3200 m and increases as the altitude increases.Activities of 137Cs in soil and dry atmospheric deposition correlated significantly,and 137Cs activity in soils and atmospheric dry depositions decrease as the absolute altitude decreases.The 50-year effective dose from exposure to 137Cs fallout varies with altitude from 0.007 to 1.42 mSv.