We present a geophysical and geocryological study of permafrost distribution and active layer thickness (ALT) in the Arctic area of Khanovey (Komi Republic, Russia). The area is crossed by a 1.5 km transect of the North Russian Railway that is experiencing serious instabilities caused by subsidence, with vertical deformations up to 2.5 cm/year. This is due to thawing permafrost, a consequence of global warming, whose effects depend on local factors, as vegetation, soil properties and land-use. We performed geocryological surveys including vegetation analysis and underground temperature measurements, together with the less invasive geoelectrical investigation. Results show landscape heterogeneity and an average resistivity of the active layer of about 80 m, while the underlying permafrost shows resistivity values higher than 200 Ωm. Due to the absence of insulating vegetation, low resistivity (<80 m) permanent unfrozen ground (i.e. talik and thermokarst lakes) occurs close to the railroad. In the study area, ALT values range between 0.5 m and 7 m. These detailed information on specific spatial variation in cryological conditions are fundamental to address the design of engineering solutions to ensure structural stability of the railway, such as maintenance of the thermal balance of the ground.

Geophysical and Geocryological Investigation of Active Layer Along The North Russian Railway (Khanovey, Russia)

Dal Cin M;Picotti S;Gei D;
2021

Abstract

We present a geophysical and geocryological study of permafrost distribution and active layer thickness (ALT) in the Arctic area of Khanovey (Komi Republic, Russia). The area is crossed by a 1.5 km transect of the North Russian Railway that is experiencing serious instabilities caused by subsidence, with vertical deformations up to 2.5 cm/year. This is due to thawing permafrost, a consequence of global warming, whose effects depend on local factors, as vegetation, soil properties and land-use. We performed geocryological surveys including vegetation analysis and underground temperature measurements, together with the less invasive geoelectrical investigation. Results show landscape heterogeneity and an average resistivity of the active layer of about 80 m, while the underlying permafrost shows resistivity values higher than 200 Ωm. Due to the absence of insulating vegetation, low resistivity (<80 m) permanent unfrozen ground (i.e. talik and thermokarst lakes) occurs close to the railroad. In the study area, ALT values range between 0.5 m and 7 m. These detailed information on specific spatial variation in cryological conditions are fundamental to address the design of engineering solutions to ensure structural stability of the railway, such as maintenance of the thermal balance of the ground.
File in questo prodotto:
File Dimensione Formato  
2021EAGEConfRossiEtAl.pdf

non disponibili

Tipologia: Altro materiale allegato
Licenza: Non specificato
Dimensione 744.03 kB
Formato Adobe PDF
744.03 kB Adobe PDF   Visualizza/Apri   Richiedi una copia

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: http://hdl.handle.net/20.500.14083/5401
 Attenzione

Attenzione! I dati visualizzati non sono stati sottoposti a validazione da parte dell'ateneo

Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus ND
  • ???jsp.display-item.citation.isi??? ND
social impact