Mofettes (image) Friedrich-Schiller-Universitaet Jena Share Print E-Mail Caption Mofettes close to the Czech river Plesná is shown. These small openings in the ground are leaking carbon dioxide, which originates in the magma chambers of the earth's mantel or the earth's crust. Credit Felix Beulig/FSU 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.