ÇAĞRILI KONUŞMALAR / KEYNOTES Invited Speeches ... - TPJD

Drilling Results 2007 – 2009 in the Western Black Sea Targeted on Neogene
Deep and Shallow Water Sediments
Alastair Gray, Atila Sefünç, Hüseyin Yıldırım
Tiway, Ankara
Prior to 2007 the only drilling in the West Balck sea ( west of Istanbu) were the Karadeniz-1(1970),
Igneada-1(1971), and Limankoy 1 and 2 (1999). The resuslts of all of these wells were negative
. Despite this, during the period 2006 to 2009 Toreador Turkey embarked upon an exploration
campaign in the western Black Sea. Well Karaburun-1(2007) was located adjacent to the
Kırklareli area to the Southwest of the previously drilled wells İgneada-1 and Karadeniz-1, The
Karaburun-1 well location was defined by seismic surveys conducted during 2007. Karaburun
targeted a basement high structure thought to be overlain by Sogucak reefal carbonates. This
premise was found to be false and the well finished in volcanics of Yemislicay with no resrvoir
potential being encountered. Durusu-1 well was identified by a 1500 km 2D marine seismic
survey which was acquired in 2006. Tertiary sediments cover the basement rocks of Istrandja
Massif and the Paleozoic istanbul Unit in Thrace Area. Basement rocks are overlain by different
stratigraphic units from Early – Middle Eocene to Miocene – Pliocene rock associations.The main
and secondary aims of Durusu-1 were to test the hydrocarbon possibilities of the Middle-Late
Oligocene aged deltaic Osmancık Sandstones and Late Oligocene-Early Miocene aged Danismen
deltaic sandstones. The Osmancık Sandstones together with Ergene and Danismen Sandstones
were encountered in Durusu-1 at the expected depths. No DST’s were performed. No core was
taken in the well. Drilling was continued down to 2510 m and Durusu-1 exploration well was
completed as a dry well on 27.08.2009. Structural and stratigraphic evaluations of 2D seismic data
laid the ground for a consistent regional framework. Seismic attributes and sequence stratigraphy
indicated that the main Osmancik reservoir interval is part of a large lowstand submarine fan
system. Analogies with recent successes in West Africa were noted. The well results are thought
to confirm the sedimentological model but unfortunately a source and migration combination
were missing.
Keywords : Seismic, Seismic Attributes, Volcanic,Well
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