DYNAMICS and ACTIVE PROCESSES - International Lithosphere ...

ILP TASK FORCE on SEDIMENTARY BASINS
2010 International Workshop
November 7-12, 2010, Tirana (Albania)
Reservoir properties of resedimented carbonates of Upper Cretaceous turbiditic
system in Albania
Rubert Yolaine 1, Jati Mohamed 1, Loisy Corinne 1, Cerepi Adrian 1, Foto Gjergji 2,
Mushka Kristaq 2
1, EGID-Bordeaux 3 Institute, 1 allée F. Daguin, 33607 PESSAC Cedex, France
rubertyolaine@yahoo.fr
2, Faculty of geology and mining, Tirana Polytechnic University, Albania
Introduction-Geological setting
The siliciclastic turbiditic systems have been largely studied motivated by their reservoir
rock potentials contrary to resedimented carbonates which did not benefit of such attention.
But several key studies of modern and ancient resedimented carbonate systems have permit to
precise the facies, the depositional models, or the controlling factors (Mullins and Cooks
1986; Einsele G. et al., 1991; Payros and Pujalte, 2008). Studies about resedimented
carbonates have allow to demonstrate their reservoir rock potential especially in coarse levels
(Casabianca et al. 2002).
The Northeastern part of Albania is an hydrocarbon bearing province with in particular
Late Cretaceous limestones which host oil reservoirs under the Peri-adriatic depression
(Xhavo, 2002). More in the south, this formation outcrops and is described as brecciated
limestones. In the Kremenara anticline, this formation displays superficial oil seeps (Dewever
et al. 2007) which allowed to describe the porosity and the factors controlling its formation.
The outcrops of Piluri and Muzina, studied here are devoid of oil seep but outcropping
conditions favour a combined sedimentary and petrographical-petrophysical study of the
Upper Cretaceous brecciated carbonates. A preliminary sedimentological study of these
brecciated limestones allowed to determine their gravitary origin. Paleogeographically they
correspond to slope and basin deposits belonging to the Ionian Basin (Zappatera, 1994).
Methodology
In Piluri outcrop, two sections were logged with total thickness reaching 227 m. At Muzina
two sections were logged, the total thickness being about 260 m. At Vanister around 150 m
thick was logged in the upper part of the succession. Several facies were defined by
sedimentological. study: fine-, medium- and coarse- calciturbidites, debris-flows, and slumps.
Sampling was performed relatively to each field facies and uncovered, unpolished thin
sections were made and observed with an optical microscope (Olympus BH-2). Petrophysical
measurements were realised with an air permeameter IPF 49 apparatus and dried cores, and
with a mercury porosimeter Micromeritics III and dried rocks fragments.
Results
Petrography
Thin section examination allowed to define seven microfacies, the various constituants and
to describe the diagenesis with additionaly field observations.
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