Contents Stratigraphic architecture of the Sonia Fluvial interval, India in its Precambrian context S. Sarkar, P. Samanta, S. Mukhopadhyay and P.K. Bose Archean cherts in banded iron formation: Insight into Neoarchean ocean chemistry and depositional processes P.C. Thurston, B.S. Kamber and M. Whitehouse lon microprobe analyses of 5'80 in early quartz cements from 1.9 Ga granular iron formations (GIFs): A pilot study L.C. Cunningham, F.Z. Page, B.M. Simonson, R. Kozdon and J.W. Valley The radiogenic isotope characteristics of dikes and sills associated with the Mesoproterozoic Midcontinent Rift near Thunder Bay, Ontario, Canada P. Hollings, M. Smyk and B. Cousens