Abstract Hydrocarbon shows have been known in northern Turkey for more than 100 years. Close to the Black Sea, several source rock units, mainly from outcrops but also from wells, have been tested for source rock potential. Organic geochemical studies on subsurface and surface samples indicate that there are several potential hydrocarbon source rock units in the region: the Kartal Formation (Early Devonian), Yilanli Formation (Middle Devonian–Early Carboniferous), Alacaagzi and Zonguldak Formations (Carboniferous), Himmetpaga Formation (Middle Jurassic), (Çağlayan and Ülüs Formations (Cretaceous), Yemişliçay Formation (Late Cretaceous) and Kusuri Formation (Eocene). The Zonguldak and Himmetpaga formations are composed of predominantly gas-prone vitrinite macerals. The coal samples from the Alacaağzi Formation have a different maceral composition consisting predominantly of sporinite, which is capable of producing oil. Four surface oil seeps, one seep from offshore of Rize, one oil show from İğneada-1 well, one gas seep from the Ülüs Basin, and one gas sample from the Akçakoca-1 well, have been analyzed using classical organic geochemical techniques (pyrolysis, gas chromatography, and gas chromatography-mass spectrometry). An attempt has been made to correlate possible source rock in the area with the Armutçuk oil seep. Results of geochemical analysis of the oil seeps from different localities in the Black Sea region indicate that they have been derived from different units.