Geology Reference
In-Depth Information
The last gradation within the utilized estimation technique is reasonably
close in its accuracy to the С
1
reserves. For this reason, it is acceptable to
treat the proved reserves of the countries and the basin as the sum of all
categories (А+В+С
1
+С
2
).
In Azerbaijan and Iran, most of the stated amounts is concentrated of-
shore - 95.45% and 83.5%; but in Turkmenistan - onshore - 67.4%.
The situation in the countries by hydrocarbon type within the indicated
reserves quality is as follows: In Azerbaijan, total oil reserves are 946.74
MMT, condensate 348.23 MMT, gas 2,632.87 BCM, hydrocarbons 3,927.83
MMT of oil equivalent. In Turkmenistan, respectively, 272.77 and 40.61
MMT, 752.87 BCM and 1,066.25 MMT of oil equivalent. In Iran, 673.4 and
14.91 MMT, 788 BCM and 1,476.31 MMT of oil equivalent. In the Basin as
a whole, oil 1,892.91 and 403.75 MMT, gas 4,173.73 BCM and total hydro-
carbons, 6,470.39 MMT of oil equivalent (Table 11.4).
As of January 1, 2006, the recoverable oil + condensate and gas reserves
depletion rate (ratio of current recoverable reserves to the original ones)
is, respectively onshore and offshore: Azerbaijan, 0.952 and 0.527, 0.291
and 0.122; Turkmenistan, 0.710 and 0.294, 0.044 and 0.035 (see Table 9.4).
Thus, both countries have largest hydrocarbon production increase poten-
tial offshore.
A serious potential for increment of the recoverable oil and condensate
reserves at substantially depleted onshore fields may be associated with the
increase in oil and condensate recovery factor due to broad application of
the secondary and tertiary production methods. According to the State
reserves balance sheets average liquid hydrocarbons recovery factor in
Azerbaijan is approved at 35%, in Turkmenistan 41%. Increase in these val-
ues by just 1% would yield the increment in the current remaining reserves
increment of respectively 30 and 15 MMT.
At the Azerbaijan and Turkmenistan offshore prospects the commer-
cial oil and gas reserves increment in the nearest term may be achieved
first and foremost through the supplemental appraisal of the lower
Productive Sequence. That may be performed in the fields Azeri, Chirag,
Gyuneshli, Kyapaz, Shahdeniz and prospects with the established oil and
gas occurrences (Ashrafi, Karabakh, Dan Ulduzu and Nakhchyvan) and
also on the structures in contract blocks I and II in the Turkmenistan
offshore of the Balkhan zone. Onshore, positive results may be expected
on a number of incompletely appraised structures in the Lower Kura
Depression (Azerbaijan) and Gograndag-Chikishlyar zone of highs (West
Turkmenistan).
The conducted estimation suggests that the undiscovered C
3
and D
1
resources in the Productive Sequence (Red-Bed Sequence) of Azerbaijan
