Scientists are on high alert after threat levels rose for three US volcanoes Thursday, suggesting eruptions may be imminent. The US Geological Survey (USGS) placed Alaska's Great Sitkin on ...

both at the University of Colorado. My main research interests are the geologic, hydrologic, and climatic histories of the planet Mars and all things related. In particular, I work on problems dealing ...

The magma rises into the Earth’s crust, where it can get trapped underground or erupt from volcanoes as molten lava. As magma or lava cools it forms a tough rock that is resistant to erosion ...