IN an extensive study, a group of geologists from the University of the Philippines has listed highly urbanized centers in the country where land subsidence is a growing problem.

The study, published in the International Journal of Applied Earth Observation and Geoinformation last September, pointed to excessive groundwater extraction and rapid urbanization as among the factors that contribute to ground subsidence, which is described as 'the gradual sinking or sudden collapse of the Earth's surface due to the settling of subsurface earth materials.'