Abstract The spread of loess soils in Golestan Province in northeastern Iran has caused numerous environmental issues. To evaluate the efect of loess collapse on the spatial distribution of pseudokarst sinkholes in this province, we have prepared undisturbed samples from 31 locations and characterized their physical and mechanical properties. Moreover, the collapse sensitivity in diferent parts of the study area has been determined by odometer tests and calculation of the collapse coefcient (Ic), the time required for 90% settlement (T90%), and initial collapse stress. Additionally, by conducting feld surveying, using aerial photographs, satellite images, and drone fight, the coordinates of sinkholes were identifed, and a map of their geographical distribution was prepared. The overlap of the sinkholes distribution map and the Ic changes map showed that although the amount of Ic of sandy loess soils (Zone III) is higher than that of silty loess soils (Zone II), the extent of destructive phenomena such as sinkholes is much greater in Zone II than in Zone III. The overlap of the map of sinkholes distribution with the map of changes in collapse sensitivity (Is) of loess soils showed that the density of sinkholes in Zone II (which has higher collapse sensitivity) is higher than Zone III. Also, the results show that with increasing initial collapse stress, the density of sinkholes increases. In Zone II, due to severe collapse sensitivity, the highest concentration of sinkholes is observed in a unit area, more than 0.18 per square kilometer. With a relatively severe to severe collapse sensitivity in Zone III, this concentration is 0.021 per square kilometer. Furthermore, in Zone I, the sinkholes (0.004 per square kilometer) have the least concentration.
