Map of Earthquakes and Injection Wells (IMAGE) University of Texas at Austin Caption This is a map showing earthquake epicenters determined in this study (red circles), injection wells (squares and + symbols) in use since October 2006, seismograph stations (white triangles), and mapped faults (green lines. Circle sizes indicate quality of epicentral location, with large, medium and small sizes indicating qualities A, B, and C. For injection wells, yellow squares are wells with maximum monthly injection rates exceeding 150,000 barrels of water per month (BWPM); white squares, exceeding 15,000 BWPM; + symbols, exceeding 1,500 BWPM. Credit Cliff Frohlich/U. of Texas at Austin. Usage Restrictions None 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.