British team discovered that damage to Earth's crust created 'real danger'

[THE FUGITIVE]

Yesterday's earthquake struck in a region where, a fortnight ago, a University of Ulster professor predicted a new tsunami might be born.
A magnitude 9.0 earthquake which created the waves that claimed around 300,000 lives last December was likely to trigger more devastation, said a paper published in the journal Nature by Prof John McCloskey and colleagues.
In the light of the preliminary data on yesterday's magnitude 8.7 quake, he said: "It looks like one of our concerns has been realised. We'll have to wait to see how bad the damage has been this time." With colleagues, he calculated that the jolt in the Earth's crust at the end of last year, which led to a vast movement of the sea bed, significantly boosted seismic stresses and increased the risk of another large earthquake on the devastated Indonesian island of Sumatra.
When his paper came out, Prof McCloskey said: "Our results indicate unambiguously that there is a real danger of another earthquake in the region. It is vital that disaster fatigue does not delay the implementation of the Indian Ocean Tsunami Warning System."
The Boxing Day earthquake which generated the massive tsunami that hit Indonesia, Thailand, India and Sri Lanka also increased the stress on two other fault zones, one running directly under the remains of the city of Banda Aceh, the other under the sea off the west coast of Sumatra.
Stresses in the latter, the Sunda Trench, could generate another tsunami, said Prof McCloskey and Dr Suleyman Nalbant and Dr Sandy Steacy, also of the University of Ulster. Last night Prof McCloskey said the preliminary indications were that the new quake was "at the northern end of the Sunda Trench".
The team analysed data from the Boxing Day earthquake to look at its impact on other faults and whether it has raised the risk of more earthquakes. First, the team used calculations made by a group of seismologists at the California Institute of technology which give the exact displacements of crust during the earthquake.
This is done by repeatedly modelling the waves that were detected by seismic stations around the world. When these synthetic waves have a very similar form to the observed waves, then scientists know that their model of the earthquake closely resembles what actually happened.
The team then estimated the effect of the earthquake in the Indonesian region by calculating the amount of stress at any point which is caused by the movements triggered by an earthquake, then studied geological maps to identify nearby active faults.
Two zones showed significantly increased levels of stress. One was in the Sunda Trench, a 30-mile-long underwater zone adjacent to the 2004 earthquake rupture. The other was in the Sumatra fault, which runs for 190 miles along the centre of Sumatra. These levels of seismic stress indicated significantly increased risk of an earthquake, said Prof McCloskey.