A combined survey to evaluate the thermal behavior of loess for a landslide-prone slope on the Heifangtai terrace in Northwest China

• Published in: Journal of mountain science Vol. 18; no. 12; pp. 3247 - 3260
• Main Authors: Zhang, Hao, Zhang, De-xuan
• Format: Journal Article
• Language: English
• Published: Heidelberg Science Press 01.12.2021; Springer Nature B.V
• Subjects: Anomalies; Distribution; Earth and Environmental Science; Earth Sciences; Ecology; Environment; Escarpments; Geography; Groundwater; Groundwater levels; Groundwater table; Inertia; Infrared analysis; Infrared imaging; Irrigation; Laboratories; Laboratory tests; Landslides; Landslides & mudslides; Loess; Moisture content; Original Article; Polls & surveys; Properties; Seepage; Solar radiation; Spatial distribution; Surface temperature; Surveying; Surveys; Temporal distribution; Thermal response; Thermodynamic properties; Thermography; Water content; Water table; China; Loess landslide; Infrared Thermography; The Heifangtai terrace; Water content; Thermal response
• ISSN: 1672-6316; 1993-0321; 1008-2786
• DOI: 10.1007/s11629-020-6643-9

A combined survey including infrared thermography (IRT) and field-laboratory tests were conducted to analyze the thermal responses and thermal properties of loess on a landslide-prone loess slope in the Heifangtai terrace in Northwest China aiming at preliminarily demonstrating the potential of IRT as a complementary technique to the investigation of irrigation-induced loess landslides. Multitemporal thermographic surveys corresponding to various solar radiation intensities during the afternoon were carried out on the landslide-prone loess slope. Accordingly, the spatiotemporal distribution of the thermal responses within the observed slope surface was analyzed qualitatively and quantitatively. Meanwhile, field and laboratory investigations were also performed on the thermal properties of different landslide materials. The results indicate that loess, a landslide-prone deposit that usually has a relatively high water content, exhibits different thermal properties and anomalies, including a lower surface temperature and greater thermal inertia, compared to surrounding zones without landslides. The groundwater table and corresponding seepage line could also be obtained by determining the potential boundary between the thermal response distribution of landslide scarps and that of saturated deposits in the presence of landslides. The results of these investigations are expected to provide insight for future endeavors combining infrared thermography with other efficient survey methodologies (e.g., InSAR, which can monitor the active displacement of a loess slope) to evaluate the activity of this kind of excessive irrigation-induced loess landslide.