Seismic Event Detection & Phase Picking Method Selection Guide

Overview: Method Tradeoffs

When choosing an event detection and phase picking method, consider these key tradeoffs:

Method	Generalizability	Sensitivity	Speed, Ease-of-Use	False Positives
STA/LTA	High	Low	Fast, Easy	Many
Manual	High	High	Slow, Difficult	Few
Deep Learning	High	High	Fast, Easy	Medium
Template Matching	Low	High	Slow, Difficult	Few

• Generalizability: Ability to find arbitrary earthquake signals
• Sensitivity: Ability to find small earthquakes

Key insight: Each method has strengths and weaknesses. Purpose and resources should guide your choice.

STA/LTA (Short-Term Average / Long-Term Average)

Advantages

• Runs very fast: Automatically operates in real-time
• Easy to understand & implement: Can optimize for different window lengths and ratios
• No prior knowledge needed: Does not require information about earthquake sources or waveforms
• Amplitude-based detector: Reliably detects large earthquake signals

Limitations

• High rate of false detections during active sequences
• Automatic picks not as precise
• Requires manual review and refinement of picks for a quality catalog

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Template Matching

Advantages

• Optimally sensitive detector (more sensitive than deep-learning): Can find smallest earthquakes buried in noise, if similar enough to template waveform