Integrated Geophysical and Temperature Sensing Techniques Towards Scalable Monitoring of Permafrost Variability in Utqiaġvik, AK
Description:
Climate change is causing an increase in permafrost thaw, affecting both anthropogenically disturbed areas adjacent to infrastructure and undisturbed tundra regions. In this research, we use multiple geophysical methods—active and passive multichannel analysis of surface waves (MASW), electrical resistivity tomography (ERT), and ground temperature sensing—to study heterogeneity in permafrost's geophysical characteristics in Utqiaġvik, Alaska. To scale permafrost monitoring spatially and temporally, we deployed 2 km of distributed acoustic sensing (DAS) and distributed temperature sensing (DTS) cables that continually record passive seismic and temperature data for a three-year duration. MASW results from the active-source survey reveal a low-high-low shear wave velocities (Vs) pattern in most locations. A notable inverse correlation is observed between in-situ Vs and ground temperature. The Vs profiles and electrical resistivity profiles reveal cryostructures such as cryopeg and ice-rich zones in the permafrost layer. Corroboration of these geophysical observations with permafrost core samples' stratigraphy and salinity measurements further validates these findings. This combination of geophysical and temperature sensing methods, along with permafrost core sampling, confirms a robust approach to assessing permafrost's spatial variability in coastal environments. Continuous imaging of permafrost seismic structure through ambient noise DAS tomography, utilizing active-source survey Vs profiles as baseline models, may provide benchmarks for the rate of change in permafrost along the Arctic Ocean coast, thereby informing climate modeling efforts. Further, our results also indicate that civil infrastructure systems such as gravel roads and pile foundations affect permafrost by thickening the active layer, lowering the Vs, and reducing heterogeneity. We show how the resulting Vs profiles can be used to estimate critical parameters for designing buildings in permafrost regions and maintaining existing infrastructure in polar regions.
Session: Applications and Discoveries in Cryoseismology Across Spatial and Temporal Scales - I
Type: Oral
Date: 5/2/2024
Presentation Time: 04:30 PM (local time)
Presenting Author: Ahmad
Student Presenter: Yes
Invited Presentation:
Authors
Ahmad Tourei Presenting Author Corresponding Author tourei@mines.edu Colorado School of Mines |
Xiaohang Ji xhji@psu.edu Pennsylvania State University |
Eileen Martin eileenrmartin@mines.edu Colorado School of Mines |
Ming Xiao mzx102@psu.edu Pennsylvania State University |
Gabriel Rocha dos Santos grd5166@psu.edu Pennsylvania State University |
Rafal Czarny rkc5556@psu.edu Pennsylvania State University |
Tieyuan Zhu tyzhu@psu.edu Pennsylvania State University |
Ziyi Wang ziyiwang@psu.edu Pennsylvania State University |
Sergei Rybakov srybakov@alaska.edu University of Alaska Fairbanks |
Matthew Hallissey mjh6708@psu.edu Pennsylvania State University, State College, Pennsylvania, United States |
Dmitry Nicolsky djnicolsky@alaska.edu University of Alaska Fairbanks, Fairbanks, Alaska, United States |
Anne Jensen ajensen@alaska.edu University of Alaska Fairbanks, Fairbanks, Alaska, United States |
Integrated Geophysical and Temperature Sensing Techniques Towards Scalable Monitoring of Permafrost Variability in Utqiaġvik, AK
Category
Applications and Discoveries in Cryoseismology Across Spatial and Temporal Scales