Foglepole Cave (IMAGE) Seismological Society of America Caption White stalagmites and associated formation are from Fogelpole Cave in southwestern Illinois (Illinois' longest cave) that were initiated by the New Madrid Seismic Zone earthquakes of 1811-1812. Credit S.V. Panno Usage Restrictions Please use credit information 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.