The aftershocks rippling across South Asia in the wake of the massive earthquake that sent killer waves crashing ashore across the region are likely to continue, seismologists said yesterday. But the seismic activity doesn't necessarily portend another major temblor.

　　"After a major earthquake has occurred, it takes time for aftershocks to die down naturally. It could be weeks, months or even more than a year," said Chan Ying Wa, a senior scientific officer at the Hong Kong Observatory.

　　In the days since the 9.0-magnitude quake struck off the coast of Indonesia's Sumatra island, India's Meteorological Department said it has logged more than 100 aftershocks of magnitude 5.0 or above occurring in the same area, which also includes India's remote Andaman and Nicobar islands.

　　Indian Meteorological Department Director R.S. Duttatrayam said the quakes have not caused any casualties or damage since most of the temblors have occurred underwater, where much of the shock is absorbed.

　　Those quakes haven't been strong enough to trigger a tsunami like the massive December 26 earthquake.

　　Residents in Port Blair, the capital of the federally administered territories, said they didn't realize the aftershocks had even hit near the islands.

　　Seismologists have repeatedly emphasized that no scientific equipment available can accurately predict a quake.

　　"There is no way to tell with any certainty whether or not an earthquake will happen," said Duttatrayam.

　　"What we normally advise in the wake of aftershocks is to stay away from buildings damaged by the main shock since those buildings could be further damaged," he added.

　　Though there's no guarantee, the data so far suggests that both the frequency and the magnitude of the aftershocks have decreased in recent days, said Wa of the Hong Kong Observatory.

　　"If we look at the aftershock information, it doesn't seem to point to increased frequency or stronger magnitude," he said. "We don't think there's a sign to suggest another big quake."

　　In the first two days after the giant waves hit south Asia and parts of east Africa, the facility measured more than 20 moderate aftershocks a day, Wa said.