Scientists studying a land bulge near Bend, Ore., think a new volcano may be forming. A group from the U.S. Geological Survey is studying the swelling in Earth's crust. It is nearly two-thirds the size of Portland, Ore.

Recent eruptions at Mount St. Helens have rekindled interest in the patch of land west of Bend in Central Oregon.

Scientists say it probably started growing in 1997 and has been rising 1.4 inches a year since. The likely cause of the bulge is a pool of magma. Larry Chitwood, a geologist at Deschutes National Forest, told The Oregonian the pooling magma is under tremendous pressure causing the Earth's surface to expand and bulge.

The uplift could be anything from the early stages of a volcano, to a pooling of liquid rock. USGS geologists admit, they just don't know.

In March 2004, 350 small earthquakes indicated magma was moving underground, but the bulge has been quiet since.

Copyright 2005 by United Press International