Friday Photo (67): Geologists in the Field – Balancing in the Middle of a River Rosalie Tostevin February 15, 2013 Geologists in the field, Photos Comments Closed When the contact falls in the middle of a river, there’s only one thing for it… On the isle of Arran, 2008 (c) Geology for Global Development 2013 By Rosalie TostevinRosalie was the Himalayas Programme Officer for Geology for Global Development and writer for the GfGD blog. She is a geochemist and a postdoc at the University of Oxford.