Station Explorer — Data & Processing

Data Source

Raw MiniSEED data from Google Cloud Storage. Network 2J, stations NCF1 (TEN-NW) and NCF2 (TEN-NE), near Duchess, Alberta, Canada. V-band channels sampled at 0.2 Hz.

Processing Pipeline

Applied in order to each station on every processing run:

1. Despiking — median-filter MAD detector removes transient spikes from each gauge channel
2. Offset removal — step-change detector finds discontinuities; fits a linear slope to 500 samples before each offset and extrapolates across it to remove jumps
3. Barometric correction — 3-parameter OLS fit s = c₀ + c₁·t + c₂·b using raw (unfiltered) pressure. Bootstrap over 1000 iterations of 7-day sliding windows; selects window with lowest MSE. Corrected strain = strain − c₂_best × pressure
4. Tidal fit — 25 harmonic constituents (Agnew 2012), plus DC offset + linear drift terms. QR decomposition. Rayleigh criterion drops constituents unresolvable given the record length. Tidal residual = corrected strain − fitted tide
5. Regional strain — 4-gauge tensor geometry (VS1=0°, VS2=45°, VS3=90°, VS4=135° clockwise). Orientation matrix produces: EA (areal), ED (E-W differential), ES (shear)
6. Tidal calibration — fits M2 amplitude in the EA channel, compares to theoretical body tide (21.20 nstrain at NCF1 latitude). Scale factor converts radians → nanostrain

Units: raw data in radians of optical phase; calibrated output in nanostrain (nɛ).

High-Frequency (C-band) Data

Use the Seismic Spectrogram tab on NCF1 to explore high-frequency data interactively.

Processing follows the Tensora report spec, Feb 2026.