reillymj writes "Despite hundreds of media reports to the contrary, Sam Bonis, a geologist whose life work has been studying Guatemalan geology, has plainly said that the dramatic 'sinkhole' in Guatemala City that opened over the weekend isn't a sinkhole at all. Instead, he called it a 'piping feature' and warned that because the country's capital city sits on a pile of loose volcanic ash, the over one million people living on top of the pile are in danger. 'I'd hate to have to be in the government right now,' Bonis, who worked for the Guatemalan government's Instituto Geografico Nacional for 16 years, said. 'There is an excellent potential for this to happen again. It could happen almost anywhere in the city.'"