Ooty, July 31: The Geological Survey of India (GSI) is extending a helping hand to the Nilgiris district administration by taking up investigations related to landslide monitoring around the district to evolve a mechanism to create an early warning system in the hills highly prone to catastrophic landslides, especially during the rainy season.

Speaking to Deccan Chronicle, Mr Thanavelu, senior geologist of Geological Survey of India, said the organisation, now a nodal agency to carry out landslide investigation acro-ss the country, has chosen Nilgiris to monitor landslides and to assist the administration in dealing with related problems.

GSI has selected Kateri belt, near Coonoor, on the Coonoor-Mettupalayam road, as the primary investigation area as frequent incidence of landslides were reported in this belt in the recent past.

Mr Thanavelu said the investigation is carried out in three stages nam-ely, geo-mapping, surface investigation and geo-physical investigation.

In the Kateri belt, with geo-mapping and soil-testing already over, GSI is concentrating on surface investigation.

In the surface investigation method, in-situ soil testing of the select area was done and in continuation of that, GSI has now taken up sub-surface investigation.

For this, drills have been made in 30 select spots around Kateri and 30 pillars installed in those spots on Thursday to monitor the movement of the soil mass.

The GSI team will regularly monitor these pillars to see whether any creeps are formed and if there is any movement of the soil mass.

Chennai
July 30: If keen-eyed visitors to Marina beach feel that the sea seems to be retreating a bit, they are right. Experts have said that Marina beach is expanding by 40 square metres every year, while the beach in North Chennai is losing 77 square metres of land annually.

This was detected in a study using remote sensing and geographic information systems by Dr R. R. Krishnamurthy of the applied geology department in the University of Madras. Dr S. Ramachandran, vice-chancellor of the university and an oceanographer, was also part of the research team. “The establishment of an artificial port in the 1880s hastened erosion on its northern part and accretion on its southern part,” said Mr Ramachandran.

Mr Krishnamurthy added that the closure of the Adyar river mouth was behind the popular perception of the sea coming closer near Srinivasapuram in Pattinapakkam, Though the expansion of the Marina beach will delight fishing communities in Nochikuppam and other hamlets, the erosion in North Chennai coast is worrisome since it continues despite construction of groynes in 2004.

“It is true that groynes have helped develop a 10 metre-long beach along a 3 km stretch in North Chennai,” said Mr Krishnamurthy. “But groynes have come late after over 749 metre of land was eroded.”

Mr Krishnamurthy’s study also shows that there is impending danger of Pulicat lake merging with the sea if enough precautionary measures are not taken.