ИСТИНА

Ice wedges are widespread phenomena in cryolithozone. The location, orientation, size and origin of ice wedges are very important for builders and operating companies dealing with infrastructure in polar and mountain regions. Frequently the parameters of ice wedges are not evident. Thermokarst developing on the ice wedges is deemed to be the dangerous process for linear engineering structures. So ice wedges and possible thermokarst concerning it are considered as hazard due to consequences of infrastructure loss. Some regional examples of thermokarst along roads and pipelines in Russia are given. Spatial and temporal aspects of ice wedge formation were illustrated. Local observations of the thawing ice wedges along roads or on the territories nearby of it have been provided in Chara Depression (Transbaikalia) during 2007-­2013. Study sites were separated on natural and anthropogenic types depending on thermokarst development: natural - where ice wedges are thawing due to climate change; anthropogenic - where ice wedges are thawing due to construction and pavement of the roads. Additionally thaw settlements were appeared during ice wedge melting and recognized by infrared camera. It helps engineers to monitoring the roads and pipelines.