Oil Shale (image) American Chemical Society Share Print E-Mail Caption Fossils encased in an Estonian oil shale. Click here to access a high-resolution version of this image. Credit Mark A. Wilson, Wikipedia Commons Usage Restrictions None Share Print E-Mail 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.