Based on the theory of airborne γ-ray field

we propose a method was for determining boundary of radioactive plume.Under the medium exchange principle

mine-body models were used to simulate plume on the ground by air-sand exchange.The results show that

after the medium exchange

difference between the simulated and theoretical plume widths is small

with the relative deviations ranging from 6.4% to 8.9% for exceptional half width in the air (2z) from 410 m to 602 m.The method can be applied to boundary determination in airborne survey.