The origin of some natural carbon dioxide gases

Abstract

Natural carbon dioxide gas issues from vents and springs in sedimentary rocks. Exploratory wells drilled for oil have produced large volumes of carbon dioxide in subsurface. Where these gases are found in quantity, limestones and igneous rocks are in close association and the origin of the gases is thus suggested. Until the advent of the mass spectrometer there was no means to investigate this problem. Gas samples were taken from representative areas and the analyses showed that the gases were derived from limestone. The isotopic ratios did not give evidence of fractionation.