USGS - Science for a changing world

Bringing Earthquake Science into Your Home

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NetQuakes strong-motion instruments enable seismologists to collect extensive data in urban areas where installing traditional seismographs is not practical. This instrument (in blue, to the right of the upended chairs) takes up very little space in a San Francisco Bay Area resident's garage. It is the size of a car battery, runs on a home wifi network and captures data on an ordinary 2GB flash drive.

Obtaining timely earthquake information has become easier with interactive earthquake maps and NetQuakes, a citizen-science program that helps scientists to understand ground shaking caused by earthquakes.

Newly updated website provides robust, real-time earthquake information

Whether an earthquake is minor or major, visitors will see an interactive earthquake map that regularly updates, can be individually tailored, and provides saved settings for future map visits.

“For all citizens of ‘Earthquake Country,’ whether they reside in our Nation’s Capital or near a major global tectonic plate boundary, the new USGS earthquake site supplies increased functionality to provide more real-time information tailored to the viewer’s specific needs,” said USGS Director Marcia McNutt. “When the ground shakes and time is of the essence, our goal is to ensure that the most timely information is at the fingertips of those who need to know.”

From the website, you can access Latest Earthquakes to:

  • zoom into and pan the world map.
  • select different basemaps, as well as overlays such as plate boundaries, faults, and earthquake hazards.
  • display earthquakes on the map by time window, magnitude, depth, and maximum recorded intensity.
  • see a list below the map updates for the current map view and settings.
  • download earthquake lists into other map interfaces such as Google Earth (KML format) and Excel (CSV).

The event page, when an earthquake is selected, has also been upgraded and provides interactive features and more information, including downloadable data files in various formats for each earthquake product, such as ShakeMap and Did You Feel It? This new event-centric view allows you to see all the information associated with each earthquake without having to jump around the website to view each related product.

A future product in development will use the same user interface to present a seamless view of recorded world-wide earthquakes current and historical. It is anticipated that this product will be released in beta format later this year.

How do we gather earthquake data?

This device, about the size of a large shoebox, records strong ground motions and sends the measurements to the U.S. Geological Survey over the Internet. The data collected is available to assist with emergency response following an earthquake.

Seismic networks detect more than 87,000 earthquakes in the United States each year, although most of these quakes are too small to be felt by people. ShakeMaps, produced by the USGS and its university and State partners, give timely and detailed information on the shaking generated by quakes larger than magnitude (M) 3.5, which are often felt, are of interest to scientists, and are occasionally damaging. While the current monitoring system delivers earthquake information rapidly and reliably, seismologists are concerned that it will not fully record the damaging earthquakes that scientists have forecasted will occur. USGS scientists, however, have developed a cost-effective solution.

What is NetQuakes?

NetQuakes is a “citizen-science” program, developed in Menlo Park, Calif., by the USGS Earthquake Hazards Program , that offers the public the opportunity to help seismologists record earthquakes by hosting portable, low-maintenance sensors in private homes, public buildings, schools, and churches — and not just in the earthquake zones of California, but wherever seismic activity is a concern in the Nation. Hundreds of volunteers now host NetQuakes instruments, which transmit seismic data via Wi-Fi networks and the Internet to the USGS.

The NetQuakes project began in 2009 and was born of observations that came out of the September 2004 M6.0 earthquake near Parkfield, Calif.

“We learned from the Parkfield earthquake that intensity of ground motion amplitudes vary far more than we had believed,” said USGS geophysicist Jim Luetgert. “We had thought that sensors placed miles apart would give a good representation of the variations in shaking. But the Parkfield earthquake showed that a much closer spacing is needed to adequately map that variability.”

It’s complicated and expensive to place traditional seismographs in the urban areas that have sprung up in many seismically active areas. Traditional seismographic stations often require:

  • additional construction, such as a poured concrete foundation,
  • vandal-proof enclosures,
  • costly equipment that takes up the same space as a refrigerator, and
  • costs about $50 to transmit seismic data per station per month.

The NetQuakes instrument, in contrast, comes in an aluminum box the size and shape of a car battery. The instrument is attached to a metal baseplate that is bolted onto a foundation or floor. Rather than using GPS to keep accurate time as many traditional seismographs do, NetQuakes uses the network time protocol used by personal computers, which queries established Internet servers.

The instruments communicate occasionally with USGS computers, and telemetry is free to the USGS because hosts allow the instrument to communicate over their household Internet service. A 2GB-flash drive stores two weeks of data in case Internet communications fail in an earthquake. The instruments rely on power from a wall outlet, but contain an easily replaced internal battery to power the instrument for up to 36 hours should electricity fail.

The researchers are not looking to NetQuakes to record low-magnitude earthquakes or for rapid determination of location and magnitude, which is the role of the existing seismographic networks. Rather, they want to record how ground motion varies across a densely spaced array of high-quality sensors — especially during the largest earthquakes, which can produce ground accelerations up to three times the acceleration of gravity (3g).

Economically deploying large numbers of instruments has required some compromises. “Tradeoffs include levels of sensitivity and a few minutes of response-time,” Luetgert said. “The data are available within 10 minutes after the earthquake and are automatically incorporated into ShakeMap updates.”

For the first deployments, organizers sought a few volunteers from engineer and scientist friends near Stanford University and the University of California at Berkeley, where the Hayward Fault runs right through California Memorial Stadium. Today there are more than 130 NetQuakes instruments in the San Francisco Bay Area. Instruments have also been distributed to each of the regional networks in the USGS Advanced National Seismic System (ANSS). Luetgert noted that great progress has also been made in the Seattle area, which now has more than 80 NetQuakes instruments hosted by volunteers.

Traditional seismic stations such as this one require a source of power (solar here), a poured concrete foundation and several square feet of space. They are not always practical to install in urban areas, and that's where NetQuakes comes in.

The Portability of NetQuakes Has Advantages

Interest elsewhere has followed earthquake activity. Three years ago a swarm of small earthquakes in central Oklahoma occurred in an area devoid of seismic instruments, so Luetgert sent five instruments to NetQuake volunteers in that area. NetQuakes instruments were also deployed in the epicentral region of the August 2011 M5.8 earthquake near Charlottesville, Va., to locate aftershocks, as well as in the damaged National Cathedral in Washington, D.C. Three NetQuakes instruments were deployed near Youngstown, Ohio, to record earthquakes suspected to be induced by fluid injection in a deep well.

NetQuakes data are also being used to help resource managers and public agencies monitor shaking at critical facilities. The East Bay Municipal Utility District is partnering with the USGS to monitor ground motion at its suburban dams and reservoirs near the Hayward Fault in the eastern San Francisco Bay Area.

“Magnitude 6.8 earthquakes rupture the Hayward Fault on average every 140 years, and one may be coming due,” Luetgert noted. “We would like to be ready to record that earthquake with high-quality seismic instrumentation from a dense network to document the effects of the shaking in an urban area. This will enable engineers to better understand why buildings didn’t stand up to the shaking, and ultimately how to build structures that can resist shaking from future quakes. NetQuakes provides a cost-effective way to achieve that goal with the help of the public.”

Related stories:

USGS Menlo Park Evening Public Lecture: Shake Alert!

Join Citizens and scientists tracking the pulse of our planet

Is the recent increase in felt earthquakes in the central U.S. natural or manmade?

Oklahoma struck by series of quakes

5.8 earthquake in Virginia

Earthquake Hazards Program deformation data sites:


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