Mathematical modeling of radon transport in the aerated zone of porositic geomedium under conditions of its stress-strain state

The article uses a mathematical model to study anomalous changes in radon volume activity at a certain point in a porous geoenvironment under its stress-strain state. The stress state of the geoenvironment is described using a stress or activation function, which is included in the model equation as a source of radon inflow along with the intensity of its emanation. The model equation is a linear ordinary differential equation of the first order, which is solved using the integral Laplace transform, taking into account the initial condition. In the resulting analytical solution, the activation function is selected in the form of two exponentials. The first exponent describes the growth of stress in the geoenvironment, and the second its unloading. As a result of computer modeling in the Maple2021 environment, calculated curves of radon volume activity were obtained, which describe bay-shaped anomalies similar to those obtained during radon monitoring at the Petropavlovsk-Kamchatsky geodynamic test site.