The Silurian hot shale is encountered in the Akkas field, which is regarded as one of the largest gas fields in Iraq. It contains 5.68 tscf of initial gas in place of which 4.55 tscf is estimated to be recoverable. There is also the potential of condensate and other prospects in deeper formations. The well test confirmed the presence of natural gas with a flow rate of 6–8 MMscfd. Silurian shale contains two organic-rich black hot shale beds that are fissile with high-gamma uranium radiation. Silurian hot shales are geologically important from different sides. Stratigraphically, Silurian graptolites are used to delineate the time transgressive depositional advance of marine clastics across the Arabian Peninsula after the melting of Ordovician glaciers. For assessment of the hydrocarbon generation in the Paleozoic of Iraq, the hot shales of the Akkas Formation are low-sulfur, high-gravity oil, condensate, and gas and are considered as an important gas-rich formation in the region. From petrological and mineralogical view, the presence of distinctive minerals and some elements are important to interpret the depositional and climatic situation at Silurian time. This chapter also sets out assumptions about Akkas gas field development.
Part of the book: Shale Gas