Pathanamthitta: Geologists are investigating whether small earthquakes induced by heavy rains could be responsible for the caving in of roads in the hilly areas of Kerala during monsoon.

The suspicion was strengthened after cracks appeared on the Headworks Road and Nilakkal-Pampa Road in Munnar on the day Pettimudi was hit by a landslide that buried over 80 people.

Some wells in Erattupetta and Maramon collapsed and small craters emerged at many places in Thrissur and Idukki districts. Ham radio operators suspected that they detected seismic waves.

Chances of small tremors high

The Western Ghats are prone to very small tremors during heavy rains that cannot be detected by any seismometer, Dr K Soman, a former geologist with the National Centre for Geological Survey, said.

In Pettimudi, it is a valley that has collapsed. Huge stones have also fallen down. There might be another force besides heavy rains that is causing all this disturbances.

A fault line passes through the region. The Geological Survey of India and others should carry out serious studies in the region, he said.

Wells collapse, small craters emerge

Wells collapsing and cracks appearing in the ground at many places are an indication of pressure building up in the interior of the earth. This suggests that at least some fault lines are active, said geologist John Matthew.

It is doubtful if heavy rains can trigger small tremors in the high ranges of the Western Ghats. This trend (of wells collapsing and craters appearing), which has been visible for three years, needs to be studied. The state has the capability to identify areas prone to natural disasters and prepare an effective disaster management plan, John said.

Nilakkal road caves in

About three-quarters of a 60-metre stretch of Nilakkal-Pampa road at Planthode in Chalakkayam has caved in. The road has sunk at least one-and-a-half foot.

A team led by the Chief Engineer of the road section of the Public Works Department a team from NATPAC assessed the situation.

Pathanamthitta District Collector PB Nooh said officials of NCESS (National Centre for Earth Science Studies) in Thiruvananthapuram will also conduct inspections in the coming days. It will be examined if the landslide was caused by any earth-related activity or if it was a normal natural disturbance, he said. If it was a case of a normal landslide, the administration will take immediate measures to prevent it. But if it is not, then long-term remedial measures will be considered, he said.

Dr V Nandakumar, director in charge of National Centre for Earth Science Studies, Thiruvananthapuram, said the study would be started as soon as a request from the Pathanamthitta district collector is received.

The centre will get to work as soon it receives the request even though it has a shortage of experts due to the COVID pandemic, he said.