the U.S. Geological Survey in Portland, Oregon, told National Geographic that the mudslide, which was up to 15 feet (4.5 meters) deep in some areas, was caused by ground made unstable by heavy rainfall.
the U.S. Geological Survey in Portland, Oregon, told National Geographic that the mudslide,which was up to 15 feet (4.5 meters) deep in some areas, was caused by ground made unstable by heavy rainfall.