ASGP (2009), vol. 79: 195-211
SOURCE ROCK PREDICTION VALUE: WORLD PROVINCES DURING LATE JURASSIC–EARLIEST CRETACEOUS TIMES AND POSITION OF WEST CARPATHIANS IN SRPV PREDICTION
Jan GOLONKA (1), Michal KROBICKI (1), Anna WAŚKOWSKA (1), Irena MATYASIK (2), Robert PAUKEN (3), Natalia J. BOCHAROVA (4), Mary EDRICH (5) & Jim WILDHARBER (6)
1) AGH University of Science and Technology, Department of General Geology, Environmental Protection and Geotourism, Al. Mickiewicza 30, 30-063 Kraków; Poland, e-mails: jan_golonka at yahoo.com, krobicki at geol.agh.edu.pl, waskowsk at agh.edu.pl
2) Oil and Gas Institute, ul. Lubicz 25a, 31-503, Kraków, Poland, e-mail: matyasik at inig.pl
3) Mobil, 107 Southridge Drive, Red Oak, Texas 75154-5811, USA, e-mail: bob at paukenart.com
4) Nortel, P.O. Box 833871, Richardson, Texas 75083, USA, e-mail: nataliya at nortel.com
5) Mobil, 1927 Foreland Drive, Houston, TX 77077, USA, e-mail: johnjmarye at gmail.com
6) Mobil, 105 Dan Moody Trail, Georgetown, TX 758628, USA, e-mail: jlwild at suddenlink.net
Golonka, J., Krobicki, M., Waśkowska, A., I. Matyasik, I., Pauken, R., Bocharova, N. J., Edrich, M. & Wildharber, J., 2009. Source Rock Prediction Value: world provinces during Late Jurassic–earliest Cretaceous times and position of West Carpathians in SRPV prediction. Annales Societatis Geologorum Poloniae, 79: 195-211.
Abstract: Thirty-six Late Jurassic–Early Cretaceous regions were evaluated to obtain the Source Rocks Predic- tion Value (SRPV). We focused on three major processes, which control the organic richness in a specific paleogeographic, climatic and tectonic setting. These three processes are biologic productivity, background sedimentation rates with non-dilution of organic richness by clastic sedimentation, and preservation of organic matter. A high or increased level of primary biologic productivity supports an increased flux of organic carbon to the sediments of the sea floor. When sedimentation rate increases, especially of fine-grained sediment, the organic matter content of the sediment also increases. Preservation of organic matter depends on domination of anoxic conditions during periods of stagnation of Carpathian basins. The debate over which of the three primary pro- cesses is the most important control on the accumulation of organic-rich facies is inconclusive. We assume that the three processes are equally important, and that the balance between them has the overriding control. The amount and richness of organic matter buried in marine sediments then depends on the balance between production and destruction, where the latter includes consumption, decomposition, and dilution. The modeling of the Source Rocks Prediction Value has placed the marginal Tethyan Ocean (Carpathian basin) among the basins, which contain the richest Late Jurassic–Early Cretaceous source rocks in the world. Using the semi-quantitative Delphi method for 36 Late Jurassic regions, which represents a single tectono-depositional province in this time, we evaluated the assessment of SRPV for each of these. The south-Caspian and Central Asia basin was ranked eighth, while the Carpathian basin ninth. The paleogeographic and paleoclimatic settings are indicated as main factors in distribution by basins of known organic-rich rocks. The high organic productivity of the Carpathian basins was caused by upwelling, as well as restricted conditions in the narrow rift basins. The Upper Jurassic organic-rich Mikulov marls representing world-class source rocks (in the southeastern Czech Republic and north-eastern Austria) and Upper Jurassic–lowermost Cretaceous Vendryně Formation rocks were used as local example in analysis of oil source deposits within West Carpathian arc. The average measured Source Potential Index (SPI) for both investigated Upper Jurassic organic rich formations is around 10 and this value fits very well the SPI pre- dicted for Carpathian Upper Jurassic using Source Rocks Prediction Value method.
