16 Dec 2025

Fiber-Optic Distributed Acoustic Sensing for Nondestructive Monitoring of Permafrost

Fiber-optic distributed acoustic sensing (DAS) has gained traction in recent years as a geophysical monitoring tool. Advancements in commercially available DAS have allowed for sub-10 m data resolution and high sampling rates (over 10 kHz), leading to the use of DAS for infrastructure change detection and localization monitoring. Using this technology, a team from the US Army Engineer Research and Development Center–Cold Regions Research and Engineering Laboratory (ERDC-CRREL) built a field campaign around monitoring changes in permafrost using DAS via a dispersion analysis of surface wave propagation. In May 2024, active seismic testing was performed on a rapidly deployed, surface-laid, nondestructive DAS array above CRREL’s permafrost tunnel. Active source testing was repeated in September 2024 to collect data that may indicate changes in the seismic response due to permafrost changes. DAS response data was also collected from an unmanned aerial system (UAS) to evaluate for potential use in standoff assessment of permafrost changes. The field campaign results indicate that nondestructive DAS arrays are likely useful in detecting and localizing changes in near-surface properties of the permafrost.

2 Sep 2021

Spatial and Temporal Variance of Soil and Meteorological Properties Affecting Sensor Performance—Phase 2

ABSTRACT: An approach to increasing sensor performance and detection reliability for buried objects is to better understand which physical processes are dominant under certain environmental conditions. The present effort (Phase 2) builds on our previously published prior effort (Phase 1), which examined methods of determining the probability of detection and false alarm rates using thermal infrared for buried-object detection. The study utilized a 3.05 × 3.05 m test plot in Hanover, New Hampshire. Unlike Phase 1, the current effort involved removing the soil from the test plot area, homogenizing the material, then reapplying it into eight discrete layers along with buried sensors and objects representing targets of interest. Each layer was compacted to a uniform density consistent with the background undisturbed density. Homogenization greatly reduced the microscale soil temperature variability, simplifying data analysis. The Phase 2 study spanned May–November 2018. Simultaneous measurements of soil temperature and moisture (as well as air temperature and humidity, cloud cover, and incoming solar radiation) were obtained daily and recorded at 15-minute intervals and coupled with thermal infrared and electro-optical image collection at 5-minute intervals.