Geology Reference
In-Depth Information
Shah-Azizbek fault. The Productive Sequence top there is encountered
at 1,875 m. Based on this analogy, we believe most favorable for the first
priority exploration are striplike positioned highs directly gravitating to
the stated fault and to the Central Caspian, Sefidrud-Karabogaz and West
Turkmenistan longitudinal and
Sangachal-Ogurchin, Milsk-Chikishlyar
and Pre-Caucasus Minor sublatitudinal faults (especially to their intersec-
tions). Such structures are available in several zones. They include: in the
Abikh Swell folding zone, Azizbekov prospect (D-6), Mamedkulizadeh
prospect (D-8), Dj. Djabarly prospect (D-17), Mushvig prospect (D-31).
Depths to the top of the Productive Sequence there are 3,000-3,400 m; in
the Sary-Chikishlyar folding, the West Chikishlyar prospect and possibly
Khanlar prospect (depths to the top of the Red-Bed Sequence is 3,000 and
4,400 m) (Figure 1.1).
Most preferable for the gas-condensate prospects are in the contract
block Alov (D-15) - Sharg (D-13) - Araz (D-19). They are associated with
a diagonal fault of the Abikh Swell and cut by large amplitude cross-faults.
There, the Productive Sequence top is at depths 2,200-3,200 m. Exploring
these structures is complicated by a number of factors. The water depths
there are up to 700 m, depths to the suggested productive intervals are
7 km and deeper, they are remote from the shore and have no necessary
infrastructure. Their exploration will be defined by the projects' econom-
ics, which depend on the long-term future-trading prices of hydrocarbons.
Besides, all these prospects are within the zone of the prevalent gas-accu-
mulation. The important issue affecting the expediency of exploration and
appraisal in the near future will be the availability of gas transport and of
its users.
Another factor must be considered in the evaluation of real geologic
potential of oil and gas occurrences in the basin, selection of optimum
exploration plays and improving drilling efficiency. The experience and
results of previous exploration and appraisal operations in the region
require mandatory consideration of the following: All drilled “dry” struc-
tures in the region fringing along the perimeter the step-block deep-water
zone and closest to its center (see Figure 1.1) are objective indicators of the
hydrocarbon generation in the Productive Sequence (Red-Bed Sequence)
and implementation mechanisms of the subsequent migration and accu-
mulation processes. From these positions, our view of the South Caspian
deep-water area is different from those postulated by some scientists (Ali-
zadeh, 2005; Babayan and Semenovich, 1996; Bagir-zadeh, Kerimov
et al
.,
1987; Kerimov
et al
., 1999). They postulate this area to have been the major
source of oil and gas generation in the region and of their lateral migration
up the regional dip. We believe that the deep-water area joining the Basin's
