Abstract <p>Article presents the analysis of the consequences of large-scale technogenic impact on the relief taking into account the block–hierarchical structure of the natural–technogenic geosystem Degelen of the Semipalatinsk Test Site. The research methodology is based on the complex analysis of cartographic materials, remote sensor data and visual interpretation. The Degelen site is one of the most representative objects for studying post-explosive surface deformations formed in the epicentral zones during underground tests in horizontal mine chambers. Natural–technogenic morphostructures are represented by single and cluster areas of disintegration, complicated in some cases by subsidence funnels. The main morphometric parameters of technogenic and natural-technogenic relief forms located on the summit surfaces and along the slopes of the Degelen massif are determined using the QGIS software package. The isolation of disintegration fields is due to erosional incisions of temporary watercourses and faults traced by lineaments. Within the blocks of natural and natural–technogenic types, subtypes of blocks of a lower hierarchical level are identified based on the results of the analysis of the leading relief-forming factors. The subsequent ranking of the blocks is carried out according to the degree of technogenic modification of the landscape.</p>