EARTH SCIENCES RESEARCH JOURNAL Earth Sci. Res. J. Vol. 23, No. 3 (September, 2019): 171-183 ENVIRONMENTAL GEOLOGY ENVIRONMENTAL Measurement of radon in soils of Lima City - Peru during the period 2016-2017 Lázaro Luís Vilcapoma1, María Elena López Herrera1, Patrizia Pereyra1, Daniel Francisco Palacios1, Bertin Pérez1, Jhonny Rojas1, Laszlo Sajo-Bohus2 1Pontificia Universidad Católica del Perú, Lima, Peru 2Universidad Simón Bolívar, Caracas, Venezuela * Corresponding author:
[email protected] ABSTRACT Keywords: soil gas radon; emanation; Lima; LR- Lima City is situated on alluvial fan deposits of rivers flowing through geological formations that contain different 115 detector; Niño Costero; river floods; alluvial levels of uranium. In this paper, a study is made on the average spatial and temporal behavior of radon gas in soils of deposits; igneous rocks. Lima City. Radon concentration was determined using the LR-115 type 2 track detector during 36 periods, of 14 days each, in twenty holes distributed in the fifteen districts of Lima City. Radon concentration in soil pores ranged from 0.1 to 64.3 kBq/m3 with an average value of 5.6 kBq/m3. The average radon concentration in soil gas was about two times lower in winter than in the other seasons. High radon values during October/November 2017 were related to the earthquakes perceived in Lima City in that period. The highest radon concentrations were found in areas of alluvial deposits whose parental material has been removed from the Quilmaná and Huarangal volcanics by the Chillón and Huaycoloro Rivers. Soil gas radon concentrations were even higher in areas closer to volcanic and less distant from rivers.