Quakesourcing

Public reports help seismologists fill the gaps within their seismic sensor networks. more than 4,000 people described the intensity and duration of last week's earthquake in Oklahoma. Credit: USGS

Earthquakes that struck New Zealand, the United States, and the Mediterranean region show how the public can help seismologists protect society from the shifting Earth just as a new generation of crowdsourced projects come into their own.

Like scientists everywhere, seismologists must accept the way budgets constrain their ambitions. Seismic sensors cost quite a bit to make, deploy, and maintain. Densely-populated regions in quake-prone regions may justify a dense network of sensors, but that leaves little money for the spaces in between. The United States Geological Survey’s Advanced National Seismic System, for example, has more than 7,000 sensors to cover more than 3,000,000 square miles. 

When each sensor is dozens or even hundreds of miles from its nearest neighbor, seismologists are blind to what is really happening. The geology between the sensors changes the way earthquakes propagate as well as the effect earthquakes have on structures at the surface.

One way to fill in the coverage gap is to sacrifice data quality for data volume. Programs like the USGS NetQuakes and Stanford University’s Quake Catcher Network deploy inexpensive seismic sensors to volunteers. That avoids the maintenance expenses that traditional seismic sensors require.

Eyewitness reports are another way the public contributes to earthquake science. Seismologists conduct after-the-fact inspections of quake-struck regions to understand the effect on local geography, roads, and buildings. But there are only so many places a handful of scientists can reach before damaged buildings get repaired. Thanks to the Internet and social media, scientists get near-instantaneous feedback on an earthquake’s effects. 

The websites such as those at the USGS and the European-Mediterranean Seismological Centre let the public report the intensity, duration, and effect of an earthquake. The public can also upload pictures of landslides, liquefaction, and building damage. EMSC scientists reported that their service receives these public reports within seconds of an earthquake - and as much as ten minutes before their servers finish processing sensor data. This tweet from the EMSC shows how quickly it received reports from Oklahoma:

A new way for the public to contribute earthquake reports comes from scientists at the University of California Berkeley. Their MyShake app runs on Android-based smartphones (iOS coming soon). It uses data from the phone’s sensors to measure shaking during a quake. That data goes to the MyShake servers (which can tell the difference between a jogger and an earthquake).

Crowdsourcing gives seismologists better data about earthquakes. And that contributes to their most important job - assessing earthquake risks. Architects, insurers, emergency responders, urban planners and many others rely on earthquake risk assessments to improve their work. That leads to earthquake-resilient architecture, better zoning regulations, and other ways to keep people safe during an earthquake.