Earth movements and seismic activity have fascinated Geophysics Associate Professor Sigurjón Jónsson since childhood when a volcano erupted nine times just 20km from his home in Iceland.

Now, as a scientist he has been close to a number of natural disasters that have left a path of destruction in their wake.

Articles in various geoscience publications have praised the work that he and his colleagues from around the world have done to provide better understanding in the cause of tremors and to help governments prepare for future occurrences.

Working with a team of international faculty, Dr. Jónsson took part in a study of Haiti that discovered an unmapped geological fault. The fault was produced as a result of the country's devastating earthquake in January.

Reported in the most recent issue of Nature Geoscience, (http://www.nature.com/ngeo/journal/v3/n11/full/ngeo992.html), the team's study found that there is a potential for a similar-sized earthquake to happen even closer to the Haitian capital, Port-Au-Prince.

The study was made up of professors from the University of Texas, Purdue University Indiana, the University of Arkansas, University of Miami, Bureau des Mines et de l'Energie, Port-au-Prince and Université d'Etat d'Haiti.

Although he was not part of the on-the-ground team in Haiti, Dr. Jónsson's contribution to the study was nonetheless vital in determining its results. He provided analysis and modeling of the InSAR (Interferometric Synthetic Aperture Radar) data as well as coseismic slip estimation and error analysis.

Scientists initially thought that the quake had ruptured the Enriquillo-Plantain Garden fault that accommodates the movement between the Caribbean Plate to the south and the North American Plate to the north.

However, using both GPS and radar interferometry measurements of ground motion, the team found that this assumption was incorrect.

Their research determined that what had occurred was a combination of horizontal and contractional slip on a previously unmapped fault called the Léogâne fault. This fault lies sub parallel to the Enriquillo-Plantain Garden fault.

It was named for the town of Léogâne, which is, situated right on top of the newly detected fault and sustained the most heavy damage in the earthquake (according to reports, 90% of the buildings were destroyed).

Since the Enriquillo-Plantain Garden fault has not broken (releasing accumulated stress) for over 250 years, it still remains a significant threat for the city.

Sigurjón signed his contract to join KAUST on April 14, 2009. That very same week Saudi Arabia was hit with a swarm of 30,000 earthquakes caused by a volcanic intrusion that came just short of the surface - only 300km north of the campus.

As the intrusion in the northwest of the Kingdom took place, the Saudi Geological Survey installed a network of broadband enabled seismometers throughout the area to measure the activity.

Although most quakes were relatively low magnitude and the highest was just 5.7 on the Richter scale, the damage to houses in the rural area of Al Ais prompted Saudi authorities to evacuate some 40,000 people from the vicinity.

Most were moved to safer ground in Yanbu and Medina until the site was determined to be stable some three months later.

While still in Zurich at the Institute of Geophysics, ETH, Sigurjón requested the European Space Agency to turn on radar satellites when above the area of the swarm.

At KAUST he used images acquired previous to the quakes and contrasted them with images bounced from earth to satellite after the event.

He then measured the ground deformation and produced a model of the activity and displacement that took place underground.

What he and his collaborators found was a rare occurrence – a thin sheet (or dyke) of molten lava that had risen to roughly two kilometers below the surface and fractured brittle crystalline rocks above the flowing magma.

The Saudi lava fields (called harrats) cover approximately 180,000 square kilometers but the specific field in question, Harrat Lunayyir, is a relatively small one.

The formation of the rift that eventually led to the creation of the Red Sea started 30 million years ago with the splitting of Arabia from Africa.

The event provided valuable information on how magma ascends to the surface and may lead to improved predictive models of dyke intrusions and volcanic eruptions in the future.

In their September 2010 article published in Nature Geoscience, Sigurjón and his collaborators warn that "the harrat fields remain active and potentially hazardous" and report that, in response to their research, the Saudi Geological Survey is increasing its program of volcanic monitoring, hazard assessment and communication.

Unlike most scientists, Dr. Jonsson's laboratory is usually outside in the open air. He spends one to two weeks every summer with students surveying in his native Iceland – an intensely active volcanic area that provides he and his colleagues with baseline data for activity elsewhere in the world. He has also been involved in fieldwork in places like the Galapagos, Azores, and Hawaii.

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Sigurjón Jónsson