By Cheryl Pellerin
Washington File Staff Writer

Washington – A federally funded consortium of U.S. universities is offering long-term access to seismology equipment for institutions around the world that are seeking to establish or upgrade permanent seismic stations.

The freely offered equipment will be of use to nations or organizations establishing or upgrading earthquake-monitoring networks and to universities for teaching and research. The equipment loans also are intended to promote cooperation and free and open exchange of data among seismologists and other scientists.

Seismology is the study of earthquakes and the Earth’s structure, using naturally and artificially generated seismic waves. Networks of seismic stations are the main tools used to study earthquakes, track underground nuclear explosions, and monitor other sources of seismic waves that travel through the earth.

The Incorporated Research Institutes for Seismology (IRIS), funded by the U.S. National Science Foundation (NSF), is offering six-channel, 24-bit data loggers, which take signals from seismometers and digitize and record them.

Data loggers also can send the data to a data management center for distribution to other seismologists.

“We’ve been using those data loggers for more than 10 years in experiments all around the world,” IRIS Director of Planning Raymond Willemann told the Washington File.

“They still operate very well, but each time they get shipped, little pieces get jarred loose and get soldered back in place,” he added. “Over time, the instruments are no longer useful for experiments where you ship them around the world, but they would be useful for permanent seismic stations.”

EARTH OBSERVATORIES

A data logger is one element of a seismic station, which also includes a seismometer inside a vault, a solar panel and sometimes a freestanding communications module.

The seismometer vault is a cylindrical tank about a meter wide and two meters deep, with a concrete pad at the bottom. The tank is mostly buried, with less than a meter of the structure above ground.

The tank contains batteries, a data system, a global positioning system receiver, communications equipment and other electronics. A solar panel and communications antenna are attached to a metal mast and installed within 4.6 meters of the seismometer vault.

Networks of such seismic stations allow researchers to study and monitor the earth. One of these, the NSF-funded Global Seismographic Network (GSN), has 128 seismographic stations in more than 80 countries on all continents. GSN provides coverage for earthquake monitoring, worldwide reporting and research and monitors nuclear explosions worldwide. (See related article.)

GSN is one of four activities of the IRIS consortium. IRIS also has a pool of portable seismometers at its PASSCAL Instrument Center in New Mexico; a data-management center where GSN, PASSCAL and U.S. Geological Survey seismology data are stored; and an education and outreach program.

Another network, the International Federation of Digital Seismograph Networks, is a global organization whose members are groups responsible for installing and maintaining seismographs within their geographic borders or globally. Members coordinate station siting and provide free and open access to their data.

IRIS offers only data loggers, not all the equipment needed to establish a seismic station, Willemann said, so IRIS is looking for institutions that will be able to secure funds for other needed elements. Data loggers also can be used to upgrade existing seismic stations.

IRIS has ongoing discussions to expand the equipment loan program to countries such as Saudi Arabia, Bangladesh, Morocco and Tunisia. Other areas not covered by established seismic networks are Central Asia, Southeast Asia, the Philippines and Thailand.

To participate in the program, institutions must have the technical capability to maintain the data loggers, describe what kinds of seismometers they intend to use with the data loggers and commit to sharing their seismic data with other institutions and nations.

AFRICA ARRAY

IRIS announced the equipment-loan program in June, after establishing a pilot version with a project called AfricaArray, organized by principal investigator Andrew Nyblade of Pennsylvania State University and researchers at the University of Witwatersrand in South Africa.

AfricaArray is a 20-year public-private initiative to promote training and research programs to build and maintain a scientific work force for Africa’s natural-resource sector, especially petroleum, minerals and water. The network will be implemented in three phases over 10 years.

On the government side, AfricaArray funding comes from NSF, the U.S. Department of Energy National Nuclear Security Administration, and the South Africa National Research Foundation. Private industry provides the rest. AfricaArray also receives nonfinancial support from organizations like IRIS.

The program’s goal is to develop and maintain geophysical training programs in Africa, promote geophysical research in Africa, establish a research support system and collect geophysical data through an observatory network to study geological processes shaping the continent.

“We can’t effectively train African students at that level unless we have a research system to support it,” Nyblade told the Washington File. “That’s where the network of seismic stations comes in.”

Once the AfricaArray is established, that model of capacity building through training and research will be used in other science fields vital to the development of Africa’s natural resources.

“IRIS would like to use this instrumentation to seed a lot more AfricaArrays,” Nyblade said. “They would like to see the instrumentation be used to help to build initiatives like AfricaArray in other parts of the world.”

More information about IRIS and AfricaArray is available on those entities’ Web sites.