CUSUM Portal: Spatio-Temporal Earthquake Anomaly Detection

Ongoing research with Dr. Woody Zhu, supported by SURF.

What it does

The portal applies sequential change detection to live earthquake catalogs to flag unusual bursts of seismic activity:

1. Fetches live USGS GeoJSON earthquake feeds.
2. Groups events into spatial grid cells and aggregates them over uniform time steps.
3. Converts magnitudes to an energy proxy using the Gutenberg–Richter relation, \(E \propto 10^{1.5M}\)

4. Runs a one-sided CUSUM on each cell’s energy series,

   \[S_t = \max\left(0,\; S_{t-1} + (X_t - \mu_0 - k)\right),\]

   and raises an alarm when \(S_t > h\), where \(\mu_0\) is the cell’s baseline mean energy, \(k\) is a slack allowance and \(h\) is the decision threshold (both scaled by the cell’s standard deviation).

5. Reports flagged cells and maps the anomaly zones over the epicenters.

Links

Open the portal View the code on GitHub