Petroleum surface oil seeps from a Palaeoproterozoic petrified giant oilfield

Melezhik, V.A., Fallick, A.E., Filippov, M., Lepland, A., Rychanchik, D.V., Deines, Y.E., Medvedev, P.V., Romashkin, A.E. and Strauss, H. (2009) Petroleum surface oil seeps from a Palaeoproterozoic petrified giant oilfield. Terra Nova, 21(2), pp. 119-126. (doi: 10.1111/j.1365-3121.2009.00864.x)

Abstract

Early Palaeoproterozoic rocks from the Onega Basin in Russian Fennoscandia contain evidence for substantial accumulation and preservation of organic matter (up to 75 wt% total organic carbon) with an estimated original petroleum potential comparable to a modern supergiant oilfield. The basin contains a uniquely preserved petrified oilfield including evidence of oil traps and oil migration pathways. Here, we report the discovery of the surface expression of a migration pathway, along which petroleum was flowing from the sub-surface. This surface oil seep, the first occurrence ever reported from the Palaeoproterozoic, appears as original bitumen clasts redeposited in Palaeoproterozoic lacustrine turbidites. The δ¹³C_org of clastic pyrobitumen ranges between −35.4 and −36.0‰ (n = 14), which is within the range of interbed- and vein-trapped fossil oil (−46 and −24‰), suggesting similar source. Biogenic organic matter, whose isotopic composition was modified during thermal maturation, is the likely source for the migrated hydrocarbon.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Fallick, Professor Anthony
• Authors: Melezhik, V.A., Fallick, A.E., Filippov, M., Lepland, A., Rychanchik, D.V., Deines, Y.E., Medvedev, P.V., Romashkin, A.E., and Strauss, H.
• Subjects: Q Science > QE Geology; G Geography. Anthropology. Recreation > GE Environmental Sciences
• College/School: College of Science and Engineering > Scottish Universities Environmental Research Centre
• Journal Name: Terra Nova
• Publisher: Wiley-Blackwell Publishing Ltd.
• ISSN: 0954-4879
• ISSN (Online): 1365-3121