ÇAĞRILI KONUŞMALAR / KEYNOTES Invited Speeches ... - TPJD

Diagenesis of the Upper Oligocene Sandstones from a Well which Located
Erzurum Around
Aynur Büyükutku 1 , Fatih Gültekin 2 , Ömer Şahintürk 3
1 Ankara University, Faculty of Engineering, Department of Geological Engineering, Ankara
2 Ankara University, Graduate School of Natural and Applied Sciences, Ankara
3 Turkish Petroleum Corporation, Exploration Department, Ankara
In the study, diagenesis of Upper Oligocene aged Kömürlü and Penek Formations sandstones
from a well which located Erzurum around at Aşkale sub-basin in the East Anatolia basin were
determined by using completely the subsurface datas (core samples). The diagenetic history
of the Upper Oligocene Sandstones from a well which located Erzurum around is described
based on petrological analysis of samples. Diagenesis in the sandstones principally involves
the progressive development of various types of cements in the following order: Calcite and
feldspar formation, smectite, mixed layer smectite-illite and smectite-chlorite authigenesis,
illite, chlorite authigenic minerals, and quartz overgrowths. After the formation of the quartz
overgrowths phases there is a dissolution phase creating secondary porosity via the dissolution
of grain framework and cement. These secondary porosity zone consist of reservoir properties
for hydrocarbon formation. Authigenic minerals affect negatively these sandstones hydrocarbon
reservoirs.
Keywords: Core, authigenic mineral, diagenesis, sandstone reservoir, hydrocarbon
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