I. Complete the following:
1. The main structural elements of
the Middle East are sedimentary basins, Arches, and Transform Faults & Normal Faults.
2. The main
sedimentary basins and sub-basins in the Middle East are Tabuk sub-basin
in Saudi Arabia, Widyan sub-basin in Saudi Arabia, Sirhan
sub-basin in Jordan, Rub A1 Khali and Ras A1 Khaimah sub-basins in Saudi
Arabia - U.A.E, Zagros Basin in Iran, Palmyra and Sinjar sub-basins in
Syria-Iraq, The Mesopotamian sub-basin in Iraq and Red Sea and
Gulf of Aden sub-basin in Saudi Arabia-Yemen.
3. The main platforms in the Middle East
are Southeastern Arabian platform, Northern Arabian Platform, and
Northwestern Arabian Platform.
4.
The Early-Late Paleozoic sequence in Northern
Saudi Arabia comprises the Jauf, Sakaka and the Berwath
(Pre-Unayzah Clastics) formations.
5. The Early-Late
Paleozoic sequence in Southwest Saudi Arabia is represented by the Khusayyayn
Formation
6. The Late
Mesozoic part of the Jurassic section in Saudi Arabia includes the Marrat,
Dhruma, Tuwaiq Mountain, Hanifa, Jubailah, Arab and Hith formations.
7. Oil and Gas Seeps in
Saudi Arabia include a 5-cm stringer of bitumen in anhydrite overlying the
Arab producing horizons, a tar seep was found at Dahl Hit in a small solution
cave near Riyadh and scattered oil seeps along the Red Sea coast,
especially in the Farasan and Dahlac islands.
8. The first oil
discoveries in the Middle East were made by the D'Arcy Company in
1901 for work in southwestern Iran at Masjidi-Sulaiman
Anticline.
9. In Saudi Arabia, the
first oil field is the Dammam Field was discovered in 1938, the
Abu Hadriya Field was found in 1939, and the Abqaiq and Qatif Fields
were discovered in 1940.
10.
Most of the hydrocarbon production in the Middle East comes from Iraq,
southwestern Iran, eastern Saudi Arabia, Kuwait, Qatar, the U.A.E. and Oman.
11. Large volumes of gas are
present in the Late Permian Khuff Formation and its equivalent
formations in Saudi Arabia, Bahrain, Qatar, Iran and the U.A.E.
12. For oil in the Middle East, the
most prolific reservoirs are the Upper Jurassic Dhruma and Arab
formations in Saudi Arabia, Bahrain, Qatar and Abu Dhabi.
13.
In Saudi Arabia and adjoining regions in the Middle East, the early Silurian Qusaiba
(Shale) Formation is the principal Paleozoic source and it generated
hydrocarbons throughout the Mesozoic and in the Cenozoic.
14.
The most important oil-reservoir rocks in the Middle East at least 80% are
carbonate, and the 20% are sandstone and most important
gas-reservoir rocks 95% are
carbonate, and the 5% are sandstone.
15.
In the Middle East, the recoverable oil and gas in the main producing countries
shows that Cretaceous rocks host 51% of the recoverable oil, and
Paleozoic rocks host 50% of the gas.
16.
The
principal cap rock in the Middle East is anhydrite, which formed during Permian
to early Miocene; and the shale, mostly Cretaceous
performs the same seal.
17.
The Zagros Basin containing two-thirds of the world's
oil and one-third of its gas in a narrow belt.
18.
In Iran, the large oil and gas accumulations of the Zagros Fold Belt are
all associated with carbonate reservoirs and the most important
are the Asmari Limestone of Oligo-Miocene age, followed by the limestone
of Albian-Campanian Bangestan Group.
- In central Oman, the principal
reservoirs are contained in Late Paleozoic clastic and Lower
and Middle Cretaceous carbonate rocks.
II.
Answer the following questions
1. What are the factors of the hydrocarbon
richness of the Middle East?
1) the accumulation of a thick
sedimentary pile throughout the Phanerozoic with a few
major interruptions and, until the late Neogene, without volcanicity;
2) excellent carbonate
reservoir rocks with both primary and secondary (fresh-water leaching) porosity
and fracture porosity;
3) wide regional
distribution of seals, anhydrite (Upper Jurassic Hith and Gotnia formations and
Miocene Gachsaran Formation) and shale (Cretaceous Nahr Umr and Laffan
formations) and seals of intermediate quality (argillaceous limestone);
4) reservoirs in
extensive shelf areas closely associated with the intrabasinal anoxic source
rocks rich in organic matter;
5) traps that are
anticlinal with extraordinarily wide clo- sures, gentle growth structures on
the Arabian Plat- form associated with the flow of Infracambrian salt or
deep-seated basement faults and traps associated with the tectonically active
Taurus-Zagros-Oman Moun- tains;
6) enormous storage
capacity of the unbreached traps;
7) the substantial
release of oil and gas from large zones of mature source rocks;
8) the formation of traps
preceding migration.
2.
What ere the mechanism of hydrocarbon generation and accumulation in the
Arabian Gulf region?
a)
Catagenetic origin and long-distance migration. The idea is based on studies of
argillaceous rocks where possible source sediments at a depth and over a
sufficient geological time generate petroleum through the "kerogen"
stage.
b)
Diagenetic origin and short-distance migration. The idea is that the carbonate
rocks have the capability to generate hydrocarbon directly from organic matter
within them without passing the "kerogen" stage.
c)
Early migration and accumulation, or the "Protopetroleum Theory". The
basis of this theory is that oil that has not yet reached a mature stage may be
generated in a shallower zone than usual for oil generation. After the
premature migration and accumulation, it finally matures in the reservoir.
3. What are the main
provinces and hydrocarbon basins in Yemen?
1.
Ma'rib-Jawf-Shabwa-Balhaf Graben System
2. Eastern Tableland
(Hadhramout-Jeza-Qamar and Sayhut Basins)
3. Red Sea Coastal Area and the
Tihama Sub-basin
4. Gulf of Aden Basin
4. Copmare between the Carbonate
source and Siliciclastic source for total sulpher, gravity, n-alkanes (CPL or
OEP), sternes, disternes, thiophenic sulphur and maturation change Parameters.
5.
What are the main oil fields in Kuwait?
1. Greater
Burgan Field 2. Bahrah Field 3. Raudhatain Field 4. Sabriya Field 5.
Minagish Field 6.Umm Gudair Field 7. Khafji Field 8. Dorra Field 9. Wafra Field 12. Umm Gudair South Field 13. South Fuwaris Field.
6.
What are the main oil and gas fields in Qatar?
1. Dukhan Field 2. ldd El Shargi Field. 3. Maydan Mahzam Field. 4. Bul
Hanine Field. 5. The North
Field.
7.
What are the main oil and gas fields in United Arab Emirates?
1. Zakum Oil Field 2. Asab Oil Field 3. Bu Hasa Oil Field 4. Margham Gas-Condensate Field 5. Fateh Oil Field 6. Bab Oil Field 6. El Bunduq Oil Field 7. Sajaa Gas-Condensate Field
8. What are the main seals and seal
Formations of southeastern Turkey
1. Lower Paleozoic Handof shale.
2. The shale and marl of
Campanian-Maastrichtian Kastel Formatio.
3. Shale of Maastrichtian-Paleocene
Germav Formation.
9. What are the main oil fields in Iraq?
1. Ain Zalah Field. 2. Butmah Field. 3. Kirkuk Field. 4. Bai l-lassan Field. 5. Qaiyarah fields. 6. Buzurgan Field. 7. Nahr Umr Field. 8. Rumaila Field. 9. Zubair Field.
10. What are the main oil and gas reservoir
rocks in Oman?
1.
Infracambrian Reservoirs
2. Cambro-Ordovician Reservoirs
3. Permian Reservoirs
4. Lower Cretaceous Reservoirs
5. Middle Cretaceous Reservoirs
6. Paleocene Reservoirs
11. What are the main oil and gas reservoir
fileds in Oman?
1. Natih Fields
in the Foreland (North Oman) Sub-basin.
2. AI Huwaisah Field in the West Oman
Sub-basin.
3. Lekhwair Field in the West Oman
Sub-basin.
4. Yibal Field in the West Oman
Sub-basin.
5. Safah Field in the West Oman
Sub-basin
6. Mukhaizna Field in the South Oman
Sub-basin.
7. Marmul Field in the South Oman Sub-basin.
8. Nimr Field in the South Oman
Sub-basin.
9. Saih Rawl Field in the Central Oman
Sub-basin.
10. Qaharir Field in the South Oman
Sub-basin.
11. Rima Field in the South Oman
Sub-basin.
12. Bukha Field in the Offshore Musandam
Sub-basin.
III.
Writhe short notes on each of the following:
1. Supergiant Ghawar Oil Field
In Saudi Arabia, the Ghawar Oil Field
is a simple anticlinal structure, with a length of nearly 200 km, a width
of 16 km
and uniform flank dips of 5-8 degrees. There are six culminations
which are, from north to south: Farzan, Ain Dar, Shedgum, Uthmaniyah,
Hawiyah and Haradh. The widely spaced structural holes
drilled in 1941 in the supergiant Ghawar oil field confirmed the existence of major
anticlinal axis, which has a total length of 400 km. the first
discovery was in the E1 Nala anticlinal in 1935. The next discovery in 1949, in the Haradh
area was followed by Uthmaniyah in 1951, Shedgum in 1952
and Hawiyah in 1953. Production from the Ain Dar began in 1951,
followed by Uthmaniyah in 1953, Shedgum in 1954, Farzan
in 1962, Haradh in 1964 and Hawiyah in 1966.
Ghawar Oil Field in the south has a simple anticlinal form to as
far north as the Huiya area, where the eastern flank shows
an offset of 10-15 km
before resuming the general north-south trend and further to the
north, a central depression bordered by marginal elevations is
developed. Ghawar Oil Field the paleostructural map of the Arab D
shows the beginning of the Ghawar structure developed by the time of the
Wasia-Aruma unconformity. There was further growth during the Eocene,
and further development is evident during the interval represented by the Eocene-Miocene
unconformity. However, by the Miocene, the development of the anticline
was largely complete. In the Ghawar Oil Field the high oil
productivity usually is associated with the calcarenitic limestone and
the gravity of the Ghawar crude oil increases from north to south, in
the 32-36 API. Well productivity
decreases from north to south, due to a reduction in reservoir thickness,
the corresponding reduction in porosity and permeability and the increasing
viscosity of the oil. The average output for the Ghawar field in 1979
was 5.09 MM.bbl\d,
and total oil production had reached 19.0 B.bbl by 1979. Total
estimated original recoverable oil reserves for the whole field are 80.3 B.bbl.
2. Harmaliyah Oil Field
In
Saudi Arabia, the Harmaliyah Field is in a relatively simple asymmetric
anticline, about 40 km
long by 15 km
wide, with the steeper, south-eastern flank showing dips of 1.5 degree.
It lies east of the Ghawar Field. Oil was found in 1971 in the Arab
D reservoir below the C-D evaporite seal and it produced 35
API oil with a 1.65% sulfur content and a 740 gas/oil
ratio. By mid 1979 the field had produced a total of 133 MM/bbl.
The original recoverable oil reserves were estimated at about 1
B/bbl.
3. Qatif Oil Field
In Saudi
Arabia, the Qatif Field was discovered in 1945, after surface
geology and gravity surveys had indicated the presence of a major north-south
anticlinal structure. Qatif is a low-amplitude,
"banana-shaped" shear fold, convex westward, probably formed by fight-lateral
displacement along basement faults and possibly enhanced by deep
movement of salt from the Cambrian Hormuz Salt. Qatif field is an enormous structural
trap measuring 44 km
long by 5-7 km wide and contains several Jurassic carbonate
reservoirs of which two, the Arab C and Arab D members of the Upper
Jurassic, are the most important, with initial production beginning in 1945.
Qatif Field, high porosities and permeabilities in the reservoirs are due
to preserved primary porosity or early diagenetic secondary porosity.
The average API gravity of produced oil is 39 for Arab C
and 38 for Arab D with initial sulfur content of 2.4%
and 1.6%, respectively. The initial and continuing production
mechanism is a water drive. Other producing oil reservoirs are Arab
A in 1948, Arab B in 1962 and Fadhili in 1963
and gas reservoir is discovered in the Permian Khuff Formarion.
In 1979, the field averaged 150,000 bbl/d and total of 620 MM.bbl.
The original recoverable oil reserves were estimated at 4.7 B.bbl
4. Khursaniyah Oil Field
In
Saudi Arabia, the Khursaniyah Field is an anticlinal, domal
structure whose major axis trends in a NE-SW direction. Khursaniyah
well-1 was spudded in1956, and discovered sour oil in all four
"members" of the Upper Jurassic Arab Formation and in a
porous calcarenite section of the Jubailah Formation. Khursaniyah
Field has verage porosities are 23% for Arab A, 25%
for Arab B, 26% for Arab C and 23% for Arab D,
while the Jubailah has an average porosity of 21%. The permeability
averages are 900 md for Arab A, 200 md for Arab B, 300
md for Arab C and 80 md for Arab D. The average thickness
of each producing zone is 11
m for Arab A, 11 m for Arab B,
32 m
for Arab C, 23 m
for Arab D and 2,050
m for Jubailah. Khursaniyah Field, the
proved oil column of the Arab A is slightly more than 366 m; that of Arab B
is 355 m
; Arab C has an oil column of 335 m; Arab D is 274 m; and the Jubailah
is 102 m.
The proved areas of each producing zone are 15,500 acres
for Arab A, 14,200
acres for Arab B, 12,800 acres
for Arab C, 11,300
acres for Arab D and about 300 acres for the Jubailah
Formation. The estimated original recoverable oil reserves for the field was
2.2 B.bbl.
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