Tectonic
Influence on Oil and Gaz Field Distribution in the
Derbel Damak,
Fayrouz1, Ayedi Ben Gacha1 (1) Entreprise Tunisienne D'Activités Pétrolières,
The Central Mediterranean Sfax basin is located East of the
North South Axis; It lies on the
The hydocarbon
potential assesment of the Sfax
basin led to the following results:
Active synsedimentary
tectonic and post carbonate reservoir deposits has the main control on oil and
gas field distribution in Sfax basin.This
latter was intensively subsident during Triassic,
Jurassic and Neocomian times. At Middle Cretaceous,
extension is synchronous with halokinesis and the
early prospects are induced.During Upper Cretaceous,
distention climaxed and NW-SE grabens are formed.
Nevertheless, Cretaceous (Albo-Cenomanian, Maestrichtian)
and Tertiary (Intra Paleocene, Oligocene and Miocene)unconformities
are recorded (in several wells)expressing compressive phases which may result
in an angular unconformity.
Distension continues during Ypresian times. Relaxation phase succeeds and EW grabens are formed.
In the middle part of Sfax
basin, the El Jem Fault is a major structural
straight NW-SE oriented that separates two petroleum provinces:
The northern one comprises three
Cretaceous plays confirmed by:
-The Sidi El Kilani oil field producing from fractured chalky Upper
Cretaceous Abiod limestones.
Its offshore equivalent is the Upper Cretaceous Miskar
gas field. -the Cenomanian reefal
Isis oil field also considered as related to an obvious extention
in the offshore of the northern province. -and the good oil shows recorded in
the Serj reefal limestones of MAH-1 and MAHE-1 offshore wells.
A younging of
these plays seems to be noted from the NE towards the El Jem
fault.This may be explained by a more important
overburdening of the series towards the major fault.
The Southern province yields Eocene and
Cretaceous plays confirmed by the
AAPG Search and Discover Article #90063©2007 AAPG Annual Convention, Long Beach, California