ÇAĞRILI KONUŞMALAR / KEYNOTES Invited Speeches ... - TPJD

Surface Geochemical Evaluation of Murzuq Basin (Libya)
Feridun Alp Uğur, Hüsnü Çorbacıoğlu, Y. Haluk İztan, Şakir Özsoy
Turkish Petroleum Corporation, Research Center, Ankara
The surface geochemical surveys as having a growing importance in petroleum exploration,
primarily determine and evaluate the light hydrocarbon (C1-C4) surface microseeps from active
oil and natural gas reservoirs at depth. A surface geochemical prospection was conducted in
northern Murzuq basin (Libya) and a total of 700 soil gas samples were collected over a 500
km2 survey area from a depth of 1.2 meters with a specially desinged soil gas probe system
and analysed by gas chromatography for methane, ethane, propane and n-butane. Selected
components were used to produce light hydrocarbon contour and dot maps, pixler diagrams
etc. in order to evaluate the distribution, magnitude and the type of the hydrocarbons trapped
in the subsurface reservoirs beneath. Since the surface anomalies can also be originated from
the fractured rocks and faulted zones, these linear anomaly features in the study area were
characterized and differentiated by using the subsurface geological and geophysical data. As a
conclusion, the Murzuq basin survey has revealed that both the correlation of the results with
the post drilling activities, low costs and short project deadlines gives a positive indication for the
more extensive use of the method in the petroleum exploration.
Keywords: Organic geochemistry, surface prospection, light hydrocarbons, Murzuq Basin, Libya
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