Field Guide 46 Cover (IMAGE) Geological Society of America Caption View of downtown Pittsburgh from Coal Hill (Mount Washington), courtesy of Joseph T. Hannibal. Credit Joseph T. Hannibal. Usage Restrictions Credit: Geological Society of America and Joseph T. Hannibal. License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.