Glacier erratics landscape and research. Researcher (upper left) carrying out research on glacial erratics, blocks of rock deposited in the landscape by ancient glaciers. These erratics are located in the Swiss Jura mountains. Research like this helps reconstruct the history of the region's geography and climate. These boulders, dating from 25,000 years ago and weighing between 10 and 15 tons, were transported 130 kilometres from the Mount Blanc region and deposited here on the slopes of the Jura mountains. Photographed in October 2012.