Shales of the Silurian Oaths Formation exposed in the southeast Anatolia were investigated by organic geochemical methods. The TOC contents range from 0.24 to 1.48 wt for the Hazro samples and 0.19 to 3.58 wt% for the Korudag samples. Tmax values between 438 and 440 degrees C in the Hazro samples indicate thermal maturity; Tmax values ranging from 456 to 541 degrees C in the Korudag samples indicate late to over maturity. Based on the calculated vitrinite reflectance and measured vitrinite equivalent reflectance values, the Korudag samples have a maximum of 1.91%R(g-v), in the gas generation window, while a maximum value of 0.79%R(amor-v) of one sample from the Hazro section is in the oil generation window. Illite crystallinity (IC) values of all samples are consistent with maturity results.