Processing and simulation of the "Croissant" multi-component DAS sensor

Carla Acosta, Ivan Sanchez, Kristopher A. Innanen, Kevin W. Hall

In 2023, the Croissant was buried and tested at the Carbon Management Canada (CMC) Newell County Field Research Station (FRS) facility as a low-cost, permanent, multi-component DAS sensor. In this work, we investigate whether the integration of compact, point-based multicomponent sensors of this kind into otherwise single-component DAS systems can overcome directional limitations and enhance seismic monitoring, while preserving the cost-effectiveness of the technology. The study is based on multi-year field data recorded between 2023 and 2025 using a P-wave vibrator along a circular source line. This experimental dataset enables the analysis of the Croissant’s response to a wide range of azimuths and offsets, allowing for an evaluation of its directional sensitivity. In 2024, a geometric DAS model was developed by parameterizing the Croissant’s fiber trajectory according to its physical design and wrapping pattern. This year, synthetic shot gathers were generated using a 3D elastic finite-difference simulation (ElasWave3D) and compared amplitudes with the field data response for validation. Results showed strong agreement between synthetic and field data: the Croissant reliably captured vertical and horizontal strain, and amplitude decay followed expected trends. The findings support Croissant’s effectiveness as a point-based, multicomponent DAS sensor. Improvements in signal to noise ratio observed from 2023 to 2025 likely reflect improved sensor coupling due to soil compaction. While each sensor currently uses ~28 meters of fiber using a gauge length of 7 meters, early results suggest that could be reduced to ~14 meters under certain conditions.