Observational Seismology

(Machine Learning Seismology)

Large destructive earthquakes

Year Magnitude MMI Deaths Injuries Event
2023 7.8 XII 57,350+ 130,000+ 2023 Turkey–Syria earthquake
2011 9.1 IX 19,747 6,000 2011 Tōhoku earthquake and tsunami
2008 7.9 XI 87,587 374,177 2008 Sichuan earthquake

Hayward Fault

History

The California Memorial Stadium

An estimated magnitude of 6.3 or greater.

Many more small earthquakes

Seismic Networks

GPS Networks

Large-N and Large-T challenge

IRIS dataset

Mining the IRIS dataset

What information can we get from seismic data?

Station Channel Codes

Station Channels Codes IRIS

  • Can you find an earthquake?

Raspberry Shake Network

What information can we get from seismic data?

How are information extracted/determined?

  • Detection of earthquakes
  • Earthquake origin time and location
  • Earthquake magnitude
  • Earthquake focal mechanism/moment tensor
  • Shake map/ground motion prediction
  • Earthquake early warning
  • "Did you feel it?"

What additional information can we get from millions of earthquakes?

  • Earthquake catalog
  • Earthquake statistics
  • Earthquake triggering
  • Earthquake forecasting
  • Fault zone structure
  • Seismic tomography
  • Volcano, glacier, and landslide monitoring

How to use these information?

  • Monitoring earthquakes and earthquake early warning
  • Understand earthquake source physics
  • Understanding the Earth's structure
  • Applying seismology to environmental science, planetary science, climate science, etc.

Earthquake monitoring and earthquake rick?

  • Before an earthquake
  • A few seconds after an earthquake
  • Hours/days after an earthquake
  • Years after an earthquake

Before an earthquake

A few seconds after an earthquake

Hours/days after an earthquake

Magnitude Mw Fault Area km² Typical rupture dimensions (km x km)
4 1 1 x 1
5 10 3 x 3
6 100 10 x 10
7 1,000 30 x 30
8 10,000 50 x 200

Years after an earthquake

  • Understand earthquake rupture process
  • Improve ground motion prediction models (GMPE)
  • Improve hazard map and building codes
  • Earthquake forecasting models

How can we better monitor earthquakes?

Instrument side
(How to collect more and better data?)

  • Dense seismic networks
  • New sensors: broadband seismometer, nodal array, and DAS (Distributed Acoustic Sensing)
  • Remote sensing, LiDAR, etc.

How can we better monitor earthquakes?

Algorithm side
(New techniques for processing data and extracting information?)

  • Many signal processing algorithms, such as, STA/LTA, template matching, filtering, etc.

  • Machine learning & deep learning

  • Numerical simulation

  • Inverse theory

  • Statistical analysis

Things to learn in this course

  • Faimilar with seismic data
  • Learn the state-of-the-art machine learning methods for seismic data processing
  • Process seismic data, build seismic catalogs, and analyzing seismicity
  • Learn basic inverse theory for earthquake location, focal mechanism, seismic tomography, etc.

The advantages of machine learning

Deep Learning (Deep Neural Networks) is a new paradigm of software development

Applications of deep learning in seismology

  • Neural Networks
  • Automatic Differentiation
  • Optimization/Inversion

Machine Learning and Inversion

09/18 Seismic Data Processing
09/25 Earthquake Detection
10/02 Phase Picking & Association
10/09 Earthquake Location & Relative Location
10/16 Focal Mechanism & Moment Tensor
10/23 Earthquake Statistics
10/30 Ambient Noise
11/06 Seismic Tomography
11/13 Full-waveform Inversion

Grading

  • Attendance and participation (50%)
  • Final project (50%)
    • Project proposal (10%)
    • Project presentation (20%)
    • Project report (20%)
  • Extra credit (up to 10%)

Questions?