Glacial Sediments Greased the Gears of Plate Tectonics
COLLEGE PARK, Md. – Earth’s fractured outer shell is composed of giant plates of solid rock that move —grinding together, sliding past or dipping beneath one another to create the mountain ranges and other major surface features of our planet and generating earthquakes, volcanoes, tsunamis and other powerful events. However, Earth’s surface has not always experienced these “plate tectonics” and questions about when this began and how it has changed through time have been much debated by scientists. (more…)