Chemical Composition of Argillites of the Cobalt Series (precambrian) and the Problem of Soda-Rich Sediments Pettijohn, F. J. ; Bastron, Harry Abstract Publication: Geological Society of America Bulletin Pub Date: 1959 DOI: 10.1130/0016-7606(1959)70[593:CCOAOT]2.0.CO;2 Bibcode: 1959GSAB...70..593P