George Cressey was a man who studied geology, which is like learning about the rocks and land around us. He loved to explore and discover new things. He was very interested in earthquakes, which happen when the ground shakes and moves.
Mr. Cressey traveled all around the world studying earthquakes and trying to figure out why they happen. He even went to places like Japan and Chile where they have lots of earthquakes. He talked to lots of people and measured things like the movement of the ground.
He learned a lot about earthquakes and became an expert in the subject. He wrote books and taught classes at universities to share what he learned with other people who also want to learn about earthquakes.
So George Cressey was a man who loved exploring and learning about earthquakes so he could teach others about them too.