Full text loading...
-
Lower Oligocene Mezardere Formation as an unconventional shale-oil system: prospective area likely to be suitable for oil field development, Thrace Basin
- Publisher: European Association of Geoscientists & Engineers
- Source: Conference Proceedings, 19th International Petroleum and Natural Gas Congress and Exhibition of Turkey, May 2013, cp-380-00087
Abstract
The Tertiary sedimentary deposits in the Thrace Basin reach to 9000 meters in thickness at the depocenter. Sedimentation commenced in the Early/Middle Eocene time and continued through Pleistocene. In this time interval, the Mezardere Formation deposited in Early Oligocene (36 m.y.) through Early-Middle Oligocene (30 m.y.) and represented by marine prodelta facies of tuffy shales, marls and seldom sandstones. In northern Thrace Basin, geochemical isotopic correlation study completed by Gurgey et al. (2005) showed that the Mezardere shale functions as the source of conventional/ commercial Gelindere oil in the Hayrabolu field, condensate associated with wet gas (C2-C4) in the Karacalı gas field and gas in the Degirmenkoy gas field. However, field sizes are small and reserves are not in crucial quantity. The genetic correlation of the Mezardere shale with various hydrocarbon types mentioned above proves that the Mezardere shale is capable of generating oil, condensate as well as wet gas. Besides, the report by DOE (Department of Energy, USA) pointed out that the Mezardere shale has 785 km2 shale-gas prospective area with average net organically rich thickness of 90 m, TOC of 2.5 wt. % and thermal maturity of 1.10 % Ro. The report made mention of the Mezardere shale to contain 200 Bm3 (Billion m3) of risked GIP and 56 Bm3 of technically recoverable gas (DOE, April 2011).