Rock fragments thrown into the air during a volcanic eruption are called

Geologists know that potassium-40 decays to argon-40, with a half-life of 1.3 billion years. if an analysis of a feldspar crystal in a sample of granite shows that 75 percent of the potassium-40 atoms have decayed to form argon-40, what is the age of the granite

Using plate tectonics and elastic rebound theory, describe why juan de fuca plate subduction produces so few earthquakes. what will happen in the future?

Sketch, label, and explain the rock cycle. your sketch should contain descriptions of all eight key processes. in addition, use sentences (no sketch) to describe why a rock might not experience the entire rock cycle.