Fourier transform infrared and electron spin resonance examinations of kerogen from the Gunflint stromatolitic cherts (Middle Precambrian, Ontario, Canada) and related materials

• Main Authors: IVANA R. TONSA, MIROSLAV P. PREMOVIC, GORAN S. NIKOLIC, PAVLE I. PREMOVIC
• Format: Article
• Language: English
• Published: Serbian Chemical Society 2000-04-01
• Series: Journal of the Serbian Chemical Society
• Subjects: kerogen; Gunflint stromatolitic cherts; electron spin resonance; Fourier transform infrared spectroscopy
• Online Access: http://www.shd.org.yu/HtDocs/SHD/Vol65/No4-Pdf/V65-No4-02.zip

Kerogen occurrences in stromatolitic cherts from the Middle Precambrian Gunflint Formation and related rocks have been investigated by the use of elemental analysis, Fourier transform infrared and electron spin reconance spectroscopies. Particular attention was paid to the structural properties of the Schreiber kerogen to allow comparison with biologically controlled kerogens from Paleozoic carbonaceous rocks. The low atomic H/C ratios (0.5) of the Schreiber kerogen indicates that this material has reached a high level of maturity. The Fourier transform infrared/electron spin resonance examinations revealed that the Schreiber kerogen contains predominantly aromatic/polyaromatic structures similar to those found in mature kerogens from Paleozoic carbonaceous rocks. The evidence from this organogeochemical comparison indicates that the Schrei-ber kerogen and mature kerogens from Paleozoic/Mesozoic carbonaceous rocks have sufficient similarity to suggest a similar origin. Consequently, this work gives strong support to the hypothesis that if the Schreiber kerogen is of biotic origin than it is derived from the remnants of various microbial organisms (mainly phytoplanktons) including a minor contribution of subtidal (stromatolite-building) cyanobacteria.