Introduction to Induced Seismicity

Some of the most attention-grabbing headlines of the first half of the 2010s were related to oil and gas operations and the potential for induced seismicity. Emotions ran high as different stakeholders from government, industry and the broader community came to terms with the possibility that human operations were affecting the stability of the Earth’s crust.

Induced seismic events are not new. However, the correlation or potential causation between conventional drilling, unconventional drilling, stimulation, disposal, injection operations and seismic activity have entered the spotlight, and researchers now have a better understanding of how the energy sector affects forces in the subsurface beneath our feet. This unit closes with a more holistic look at the public concerns about oil and gas operations, particularly hydraulic fracturing.

Why It Matters

The scale of oil and gas operations is changing as new technologies unlock previously unknown or uneconomic reserves. These changes place more and more people in close contact with operations and place different kinds of stresses on those relationships. Being educated on the best management practices for mitigating risks to neighbors and the newest technologies available to address public concerns helps all stakeholders work together toward the future.

Learning Objectives

  • Understand the difference between brittle and ductile behavior of rock
  • Understand the three principal stresses in the earth and how they relate to faults
  • Understand basic earthquakes and how they are related to plate tectonics
  • Describe magnitude and intensity scales for earthquakes
  • Explain the process of induced seismicity and how/when pre-existing faults may play a role in induced seismicity
  • Describe examples of when injected fluids have potentially caused induced seismicity
  • Explain a basic traffic light system approach to regulating injection operations
  • Understand the important role well construction plays in protecting the environment

Images: “House Damage” by Brian Sherrod, USGS