Characteristics of Lower Silurian Rocks as an Unconventional Resource in Diyarbakir Basin, SE Turkey

Abstract

Increasing demand for alternative energy sources leads to an interest in unconventional hydrocarbons in Turkey as in all over the world in that Dadas Formation, one of the proven source rocks in the region, has been taken so much attention in terms of unconventional potential based on its geochemical and mineralogical properties. In this study, stratigraphically lower part of Dadas Formation, Landoverian to early Wenlockian in age, were evaluated as prospective shale oil/gas sources in Diyarbakir Basin, SE Turkey. Core and cutting samples of several wells were analysed within the scope of this study in Diyarbakir Basin. The new organic geochemical, mineralogical and palynological data incorporated with the well logs and core data were used to reveal the unconventional hydrocarbon potential of lower Silurian source rocks. As a result, lower part of Dadas Formation is divided into five subdivisions from “a” to “e” based on the geochemical, lithological-mineralogical and biostratigraphic differences. The subdivision-c which is mainly composed of dark colored, organic rich shales shows the best source rock potential based on the geochemical analyses. The organic matter content (TOC) is remarkably high up to 7 wt% with an avarage of 3–4 wt% as oil-prone Type II kerogen. Quartz content is around 30–40 wt% and clay content is between 30 wt% to 45wt% in this best source rock zone. Moreover, Tmax values of the lower part of Dadas Formation varying between 442 oC and 465 oC show that the thermal maturity increases towards to the north with increasing burial depth in the region.

AAPG Datapages/Search and Discovery Article #90194 © 2014 International Conference & Exhibition, Istanbul, Turkey, September 14-17, 2014