Hydrocarbon Systems of the Ghadamis and Murzuk Basins, West Libya and Their Relation to Al Qarqaf Arch

By

 Yahya Ahmed Al Fasatwi¹, Amin A Missilati¹, Paul M. Van Dijk²

(1) Biruni Remote Sensing Centre, Tripoli, Libya (2) ITC, Enschede, Netherlands

 The Ghadamis and Murzuq Basins, west Libya, located within the African Shield, are major producers of hydrocarbon in the western part of Libya. Since 1958 more than seventy oil and gas fields have been discovered in the two Palaeozoic basins which are separated from each other by the east-west running Al Qarqaf Arch. The Murzuq Basin is the lesser explored of the two.

In this paper, the hydrocarbon accumulations of the Ghadamis and Murzuq Basins are investigated and grouped based on data collected from about seventy oil and gas fields. The work includes classification of different reservoirs and their relation to the geographic distribution of oil and gas fields. The reservoir characteristics indicate that the Ghadamis Basin hydrocarbons have accumulated mainly in combination and stratigraphic traps in areas close to Al Qarqaf arch, and in structural anticline traps in areas close to the centre of the basin. In the Murzuq Basin, hydrocarbons are trapped mainly in structural faulted anticline traps. The lithology of all reservoirs is mainly sandstone. In the Ghadamis Basin the depositional environment ranges from shoreline in areas close to Al Qarqaf to shallow marine in the centre of the Libyan part of the basin. The depositional environment for discovered Murzuq Basin oil fields is mainly shallow marine.

The distribution of oil fields in the Ghadamis and Murzuq Basins appears to be confined to a regional trend, which reflects a close relationship between tectonics, sedimentation, oil migration and accumulation.