TITLE:
An Integrated Appraisal of Burgan Reservoir in Soroosh Oil Field, Using Petrographic and Petrophysical Approaches
AUTHORS:
Davar Ebrahimi, Abdolhossein Amini, Ali Solgi, Elham Hajikazemi
KEYWORDS:
Burgan Formation, Reservoir Quality, Sequence Stratigraphy, Soroosh Oil Field, Persian Gulf
JOURNAL NAME:
Open Journal of Geology,
Vol.6 No.9,
September
8,
2016
ABSTRACT: The
Burgan Formation in northwest of the Persian Gulf is applied to lower part of Albian
age Kazhdumi Formation, where is dominated by coarse to medium terrigenous facies.
It is the most susceptible siliciclastic unit in the area to hydrocarbon
reservoir. This reservoir is studied in a well of Soroosh oil field with best available data to determine its facies characteristics, sequence
stratigraphy and reservoir quality. Based on the petrographic results and log
data, 7 facies are determined
in the formation, which are mainly composed of sandstone and shale. These facies are classified
into three facies associations (FA) based on their sedimentological properties and
environmental conditions. The first FA consists of sandstone, siltstone and
shale, mostly developed in the lower part of formation, and is related to a fluvial environment. The second FA consists of
fluvial sandstones and sandwich by marine shales and is
related to fluvial-dominated shallow marine setting (estuary to delta). The
third FA consists
of limestones of chemical and biochemical origin and is related to a marine condition. According to their reservoir quality, these facies
associations show a decreasing trend in porosity and permeability values from
FA1 to FA3. The first FA is more abundant in the lower part of the Burgan
Formation where causes a good reservoir quality trait. FA2, presenting a medium
reservoir quality, is more frequent in the middle parts of studied formation
and FA3 is found almost in the upper parts. Based on the results from this study, three 3rd order sequences have been identified.
Sequences 1 and 3 are partial but the sequence 2 is the main and most complete
one of the formation in the studied area. The paleosol horizons are used for
relative sea level change analysis of the formation in sequence stratigraphic
studies.