Statistical Properties of Induced Earthquakes (Internship) King Abdullah University of Science and Technology (KAUST)

Overview

Induced seismicity is a central issue in the development of subsurface energy technologies in the kingdom and around the world.

Examples include subsurface wastewater injection, reservoir impoundment in the vicinity of large dams, development of mining, geothermal or hydrocarbon resources, and in geologic carbon sequestration. While most of the induced earthquakes are fortunately too small to be felt, some can go up to magnitude 5—large enough to be felt and to cause damage to buildings. 

Key Facts

Quantifying the statistical properties of induced seismicity is essential to successful management and mitigation of the seismic risk associated with subsurface energy technologies. A fundamental statistical relationship in seismology is the Gutenberg-Ricter frequency-magnitude relation. It describes the frequency of earthquakes as a function of their magnitude. 

It is usually expressed as: log10 N = a - b M, where N is the number of earthquakes with magnitude ≥ M, a is a constant that represents the total seismicity rate in a given region and time period, b is the b-value, typically around 1 for natural earthquakes, which characterizes the relative likelihood of small versus large earthquakes, and M is the earthquake magnitude. The b-value associated with induced earthquakes is a subject of ongoing debate and uncertainty.