Organic Facies Characteristics of the Triassic Ispartaçay Formation, Antalya Nappes, Western Taurus, Turkey

In the Antalya Nappes (SW Turkey), the Triassic Ispartaçay Formation consists of radioaria, chert, turbiditic limestone and sandstone. Detailed data from thick Triassic sediments (Ispartaçay Formation) made it possible to construct an organic facies framework using different zonation. Organic matter is composed predominantly of woody material, with a minor contribution of planty and woody material. Kerogen in the deposits is type III, as indicated by organic petrographic observations and Rock-Eval data. Total organic carbon (TOC) values are generally between 0.16 and 1.36%, but reach 5.24% in the formation. Tmax values vary between 331 and 602 °C, confirming the increase in maturation trends indicated by vitrinite reflectance data. Organic facies type D was identified in the investigated units. Organic facies D is related to sandstone and limestone litofacies. This facies is characterized by average values of HI around 18 (equivalent to type III kerogen), TOC around 0.85%, and an average of S2 of 0.19 mg HC/g of rock. The organic matter is highly oxidized, decomposed and reworked. Organic facies D is no generative.