LOCATION : The two blocks are locating in the western side of the central part
of the Gulf of Suez basin west of October fields.
NORTHEAST OCTOBER & NORTH ISSRAN BLOCKS 1&2
N. ISSRAN BLOCK NE OCTOBER
NORTHEAST OCTOBER BLOCK 1
NEARBY FIELDS :
E. Tanka, GS 172 , GS 173 ,
NO-183 & October oil
fields, SB 276 & GS 277 for
BP Company.
N. Amer for GPC Company.
NW October for EGPC.
1 NORTHEAST OCTOBER BLOCK
AREA : 254 km2 WELLS : 5 Wells
PREVIOUS CONCESSIONNAIRS :
AMOCO, CONOCO and DEMINEX Co.
SEISMIC SURVEYS : - 2D seismic (2942 km)
- 3D seismic (313 km2 )
2D &3D SEISMIC COVERAGE 1
Zeit Co./Devon
S. October
2005
GUPCO
E. Tanka
95
Survey
Name
41 km2 272 km2 Coverage
Dana
Petroleum
GUPCO Operator
Petrographics Processing
Center/Year
NORTHEAST OCTOBER BLOCK
3D GUPCO E. Tanka 1995 = 272 km2 3D Zetico/Devon S. October 05 = 41 km2
NO. WELL NAME / NEW NAME
COMPANY SPUD. DATE
COMP. DATE
LAT.
LONG.
T.D. FEET
FORMATION REACHED
FINAL STATUS
1 TANKA -2
(Gi 80-10 ) AMOCO
13/08/1991
07/10/1991
28° 56’ 37.0”
32° 55’ 59.0” 15,250
MIOCENE
CLASTICS
P & A
Oil shows in
Rudeis
2 TANKA -1
(Gi 80-5 ) AMOCO
19/10/1990
03/12/1990
28° 56’ 12.6”
32° 57’ 27.1” 12,233 THEBES P & A
3 NO 147 -1
(Ha 80-2) AMOCO
18/05/1990
17/08/1990
29° 01’ 25.9”
32° 54’ 33.1” 14,308 NUBIA
P & A
Oil shows in
Eoc. & U. Cret.
4 C4NA -2
(Ha 79-2) CONOCO
18/11/1984
13/01/1985
29° 00’ 59.2”
32° 50’ 40.1” 10,770 NUBIA
P & A
Oil shows in
Eocene & U.
Cret.
5 DD 83 -1
(Ha 80-1) DEMINEX
14/06/1979
14/10/1979
29° 02’ 05.7”
32° 55’ 27.9” 14,297
U. CRETACEOUS
"WATA"
P & A
Tested 45 BO
of 17° API
from Thebes &
Oil shows in
Matulla.
1 NORTHEAST OCTOBER BLOCK
NORTH ISSRAN OFFSHORE BLOCK 2
NEARBY FIELDS :
E. Tanka, GS 172 , GS 173 ,
NO-183 & October oil
fields for BP Company.
N. Amer and Issran for GPC
Company.
NW October for EGPC.
2 NORTH ISSRAN OFFSHORE BLOCK
AREA : 404.6 Km2 WELLS : 12 Wells
PREVIOUS CONCESSIONNAIRS :
PETROSA, DOVER, BG and TREND Co.
SEISMIC SURVEYS : - 2D seismic (3653 km )
- 3D seismic (521 km2 )
2D &3D SEISMIC COVERAGE 2
E. Wadi
Araba 98
PETZED
Ezz EL
Orban 08
GUPCO
E. Tanka
95
Survey
Name
229 km2 135 km2 157 km2 Coverage
M.C.
(multi
client)
PETZED GUPCO Operator
PGS Western
Geco
Processing
Center
NORTH ISSRAN OFFSHORE BLOCK
3D GUPCO E.Tanka 1995 = 157 km2 3D PETZED EZZ EL ORBAN 2008 = 135 km2 3D (Multi clients) E.WADI ARABA 98 =229 km2
NO. WELL NAME / NEW NAME
COMPANY SPUD. DATE
COMP. DATE
LAT.
LONG.
T.D. FEET
FORMATION REACHED
FINAL STATUS
1 DEEB – 1 PETROSA 08/05/2009
28/08/2009
29° 00’ 48.8”
32° 49’ 22.4” 10,111 RAHA P & A
2 EWA – 2 DOVER 03/12/2002
07/01/2003
28° 57’ 13.7”
32° 40’ 54.6” 17,055 MATULLA P & A
3 EWA – 3 DOVER 02/12/2002
20/01/2003
28° 57’ 13.7”
32° 40’ 54.6” 7,310
U. CRETA.
"RAHA" P & A
4 SHAMS -1
(Ha 78-5) BG
02/02/1993
22/02/1993
29° 00’ 29.0”
32° 44’ 33.8” 5,070 EOCENE P & A
5 NIGMA -1
(Gj 79-4) BG
02/12/1992
27/01/1992
28° 56’ 00.1”
32° 48’ 03.9” 11,600 NUBIA P & A
6 LULI -1
(Gj 78-1) BG
08/09/1990
11/10/1990
28° 58’ 40.4”
32° 44’ 36.6” 7,860
U. CRET.
"RAHA" P & A
7 GI 78 -1
(Gi 78-1) TREND
07/05/1989
23/08/1989
28° 52’ 36.4”
32° 46’ 31.9” 10,537 NUBIA
P & A Oil shows
in Matulla
8 GI 78 -2
(Gi 78-2) TREND
08/02/1989
07/03/1989
28° 56’ 25.8”
32° 44’ 16.6” 6,919 NUBIA "C"
P & A, Oil shows
in Miocene sands
& Matulla
9 SABIL -1
(Ha 78-3) UNION
05/05/1986
14/09/1986
28° 00’ 48.7”
32° 47’ 20.1” 10,500 NUBIA "C"
Non Commercial tested 225 BOPD
from Zeit Fm.
10 C4 NA -1
(Ha 79-1) CONOCO
20/10/1983
26/12/1983
29° 00’ 33.0”
32° 49’ 36.5” 10,440 NUBIA
P & A, Oil shows
in Eocene Fm
11 THELMET NW -1
(Ha 78-2) UNION
30/07/1981
26/08/1981
29° 00’ 29.0”
32° 46’ 17.6” 9,050 NUBIA P & A
12 EE 81 -1
(Gj 78-1) DEMINEX
05/01/1980
03/04/1980
28° 54’ 24.6”
32° 45’ 30.6” 7,874 NUBIA
P & A, Oil shows
in Eocene & L.
Senonian
NORTH ISSRAN OFFSHORE WELLS 2
STRATIGRAPHY : The stratigraphic sequence of
the block is shown in the fig., nearly a full Miocene
and Pre-Miocene succession are present forming all
the hydrocarbon elements.
SOURCE ROCKS :
- The upper Senonian brown limestone.
- Wata and Raha of Nazzazate group.
- Shale of L. Rudeis Fm.
RESERVOIRS :
- Nubian sandstone.
- Upper Cretaceous (Wata& Raha fms).
- Sandstone of Nukhul and Asl Fms.
SEALS :
- Shales and limestones in U. Cretaceous.
- The Miocene evaporites and shales.
Petrosalam Co., 2011
Stratigraphic Column of NWO Field
1&2 NORTHEAST OCTOBER & NORTH ISSRAN BLOCKS
Source and Oil Migration:
Source rocks in the area are:
- The mature Eocene Thebes
- Upper Cretaceous brown
limestone.
It is believed that the hydrocarbon
present in this block comes from
Issran, West October and Lagia
basins.
1&2 NORTHEAST OCTOBER & NORTH ISSRAN BLOCKS
REGIONAL STRUCTURAL CROSS-SECTION SHOWING RELATIONSHIP OF THE TWO BLOCKS & LAGIA TROUGH “ KITCHEN”
1&2 NORTHEAST OCTOBER & NORTH ISSRAN BLOCKS
PETROPHYSICAL STUDY ALONG WELLS (C4NA-1, C4NA-2, NO147-1 & DD83-1)
It is evident from the
petrophysical analysis that the
Eocene Thebes limestone has net
pay encountered in all the wells
where it is intersected, with
varying degrees of potential across
the different wells of the area.
Stimulation and/or hydraulic
fracturing of the Thebes Fm. is
required.
Further wells should be
planned towards the regions
where the Thebes Fm is
structurally at its highest position,
as this study shows that it leads to
higher effective porosity and
higher net-to-gross ratio.
1&2 NORTHEAST OCTOBER & NORTH ISSRAN BLOCKS
NORTHEAST OCTOBER BLOCK
DEPTH STRUCTURE MAP ON ASL FORMATION
The Asl Member of
Rudeis Formation
shows some prospects
in the southern part of
the block. The
sandstone of the lower
part of Asl Mb is
productive in the fields
around the area (e.g. N.
October field) and
must be tested.
1
NORTHEAST OCTOBER BLOCK
RESIDUAL MAGNETIC MAP
Aeromagnetic data indicates several positive and negative anomalies in the area. The anomalies are
expressed as noses and closures in contours .
The magnetic data and model confirms the presence of a basement high structure, as well as the
presence of a NNW-SSE trending west bounding faults.
BASEMENT SHAPE MAP
1
NORTH ISSRAN OFFSHORE BLOCK
The Rudeis structure map
in the northeastern part of
the block showed Many
prospects. these closures
must be tested.
They are tilted fault blocks
and structurally highs.
PROSPECT MAP IN NE PART OF NORTH ISSRAN BLOCK
2
1 NE OCTOBER & N. ISSRAN
(1&2) NE OCTOBER & N. ISSRAN BLOCKS
LOCATION:
The two blocks are locating in the western side of the central part of the Gulf of
Suez basin west of October fields. NE October block covers 254 Km2 with 2942
km 2D seismic and 313 3D seismic, the block comprises 5 (five) wells. While
N. Issran block occupies an area of about 404.6 km2 and has 3653 km 2D
seismic lines and 521 3D seismic, it comprises 12 (twelve) wells.
EXPLORATION HISTORY:
- Exploration history dates back to 1979 when Deminex acquired the area.
- The wells were drilled in the block subsequently by Union, British Gas and
Dover.
- The Sabil-1 well was drilled by Union in 1986 to test NW-SE trending,
easterly tilted fault block on the northern extension of the Bakr-Amer
regional structural trend. The well was drilled to the Nubia sandstone at TD
10,500’. Drilling problems were recorded and the well, nevertheless,
encountered significant hydrocarbon shows throughout the section except
225 BOPD of 22o API was flowed from the basal sands of Zeit Formation.
- In 1995 BG Egypt announced commercial discoveries in EGB-1 and Sabil-1
and signed the south Zaafarana Development lease.
- The Development lease was surrendered on September 12, 1997 after three
years of discovery, as the operator did not produce oil on regular basis
according to the terms of the Agreement.
- In 2005 Arabian Oil Company (AOC) worked in the area and drilled two
successful wells (NWO-1 in 2006) and (NWO-2 in 2010). Those wells were
tested oil with very encouraging rates through three reservoirs (Nukhul,
Mokattam & Thebes Fms). In 2010 the Arabian Oil Company declared the
commercial discovery of “Northwest October” Field.
2 NE OCTOBER & N. ISSRAN
HYDROCARBON POTENTIAL:
- SOURCE ROCKS:
Oil analysis on ten oil samples from various fields surrounded the Issran
trough indicate that the oils are all generated from mature marine carbonate
source rocks, i.e. the Thebes (Eocene) and Brown limestone (Senonian)
Formation.
The area lies in the oil migration path of two different basins namely West
October (to the east) and East Issran (to the southeast) at different times and
has different qualities; Lagia basin has also a great effect on the area.
- SEALS:
Shale and limestone in the Raha and Matulla formation for Nubia
reservoir.
Some major shale sections within Late Miocene for Eocene and Miocene
reservoirs.
- RESERVOIR ROCKS:
Lower Cretaceous sandstone (Nubia “A” Formation).
Upper Cretaceous (Matulla and Wata formations).
Eocene -Thebes & Mokattem Limestone.
Multiple sand-bearing horizons of Miocene (Nukhul, Rudeis, Kareem &
Zeit Fms.).
Summary of NE October Block Wells
TANKA-2 well (1991)
- Hydrocarbon shows were found in Asl Formation (where the best porous
and permeable intervals of the well are found). However, even though
reservoir rocks were present, hydrocarbons quantities were small.
3 NE OCTOBER & N. ISSRAN
NO 147-1 well (1990)
- The NO 147-1 was designed to investigate the crested position of a north –
easterly dipping Pre-Miocene tilted faulted block up dip from a DD 83-1
well, which had showings in the Matulla and Thebes Fm.
- The Nubia reservoir was the primary objective, while the potential
reservoirs in the Nezzazat and Asl Fm. provided the secondary objectives.
- Hydrocarbons are found in three formations Sudr, Duwi and Thebes
formations. In the Duwi, since the permeability is very low and the
formation shows the characteristics of a source rock, it is not likely that
this formation can become a good producing zone.
- The Thebes Formation has high hydrocarbon saturation. The sonic data
shows the presence of secondary porosity. The porosity is quite good (net
pay porosity 12.65%), with the best porosities (up to 18%) being found at
the top of the formation, however the average permeability is low (net
pay permeability 5.93 mD).
- The best porosity and permeability of the well are found in the Nubia
Formation. However, no hydrocarbons have been found in this formation.
C4NA-2 well (1985)
- The C4NA-2 well was drilled to test the Nubia sandstone of a high standing
horst block on the east dipping flank of the Gulf of Suez.
- The well was terminated before reaching the Nubia sandstones due to the
lack of an up dip seal at the Matulla level. The Nubia sandstone was
expected to be water bearing also.
- Evaluation of the well results suggests that the C4NA-2 was drilled in
a downthrown block to the west of the target fault block.
- Hydrocarbons were found in the Thebes, Duwi and Matulla formations.
- In the Duwi since the permeability is very low and the formation shows the
characteristics of a source rock.
- In the Matulla, even though reservoir rocks are present, hydrocarbons
quantities are small.
4 NE OCTOBER & N. ISSRAN
- The Thebes Formation has hydrocarbon saturation (SW 15.15%). The sonic
data shows the presence of secondary porosity. The porosity is good
(24.53%), however the average permeability is low (2.14 mD).
- Hydraulic fracturing of the formation would then be recommended in
order to produce the available oil.
DD 83-1 well (1979)
- DD 83-1 was drilled on the margin of a fault block trap; it was bounded on
the southwest by a major clysmic antithetic fault complex.
- Major objective: Nubian sandstone of the Albian (lower Cretaceous).
- Secondary objective: Cretaceous sandstones of the Matulla and Raha
formations.
- Hydrocarbons were found in the Thebes Formation and during the well
flowed 45 bbls of oil
- The Thebes Formation has high hydrocarbon saturation (SW 9.2%). The
sonic data shows the presence of secondary porosity. The porosity is good
(12.37%), the best porosity (up to 20%) being found at the top of the
formation, however the average permeability is low (7.6 mD).
- Hydraulic fracturing of the formation would then be recommended in
order to produce the available oil.
Summary of Issran Block Wells
EWA-3 well (2003)
EWA-3 was a deviated hole from EWA-2 vertical hole, this to test the Matulla
and Nubia sands reservoir as primary target, and Belayim and Thebes
dolomites as secondary target, and to test the southeast extension of the four
way dip closure on top Belayim and top Thebes.
Two core intervals were obtained from the top Belayim and top Thebes
fractured dolomites. No oil shows were observed in both dolomites
sections. However, the Thebes Formation core did have horizons of
organic rich dolomites with source potential.
5 NE OCTOBER & N. ISSRAN
EWA-2 well (2003)
- This well drilled to test the four way dip closure on top Nubia.
- Primary objectives were Belayim and Thebes fractured dolomite.
- Secondary targets were Pre-Miocene (Matulla and Nubia) reservoir.
- Due to mechanical hole problems, the well was bottomed in the
uppermost part of Matulla at a depth 5189 ft, and could not reach the
Nubia reservoir target.
- The drilling was very difficult because of the loss of drilling mud due to the
presence of huge fractures. No oil / gas shows were reported during the
drilling of these fractures and log evaluation confirmed that these fracture
carbonates were water bearing.
- The structural re-interpretation indicated that the well was drilled in a
part of the extension of the Wadi Araba structure into offshore area. The
well block continued uplifting during the late cretaceous.
- A decision was therefore made to terminate the well and drill a sidetrack
hole to test the updip section of Belayim and Eocene fracture carbonates.
SHAMS-1 well (1993)
- The primary target is the Sandstones of the Rudies and Nukhul Formation,
with secondary potential in the Belayim and Kareem Formation.
- This well aimed to test the up dip terminus of the hydrocarbon generating
kitchen of the Issran trough and to confirm the quality of Miocene
reservoir.
- Unfortunately the encountered reservoirs: Belayim, Kareem, Rudeis, and
Oligocene were water bearing while the Nukhul Formation was absent.
- No gas shows were encountered in the well, except a very weak
background gas starting from 4424 ft. down to the total depth.
- No oil shows were traced in the well, except at 2790'/2800' and 3280' very
weak oil shows were found.
6 NE OCTOBER & N. ISSRAN
NIGMA-1 well (1992)
- Primary objective was Nubia while the secondary target is the Miocene
clastic and Eocene fractured limestone.
- The well encountered a full Miocene and Pre-Miocene succession and
bottomed in Early Cretaceous Nubia sandstone.
- The entire Brown Limestone section, local intervals in the Thebes
Formation and the upper most part of Matulla Formation contain oil-
prone source rock with good to excellent oil generating capacity. Gas-
prone source rock with fair hydrocarbon generating potential; on the
other hand, are encountered in Wata and Malha Formation, while rocks
with oil and gas generating abilities are present in localized intervals in
Thebes, Matulla and Wata Formation.
- The Pre-Miocene section analyzed in this well contains organically rich
rocks with the potential to generate hydrocarbons. The organically rich
intervals from Thebes Formation (8880-9060 ft, 9090-9210 ft and 9240-
9330 ft), the Brown Limestone Formation (10020-10090 ft) and the upper
part of the Matulla Formation (10170-10200 ft) have good to excellent oil
generating capacity.
- Quick look interpretation and reservoir evaluation for the potential
reservoirs showed that all are water wet except the Brown Limestone of
Duwi Formation.
- A detailed interpretation and reservoir evaluation was made on this
interval using the Elan program indicated the possibly of an oil bearing
reservoir in the Brown Limestone formation.
- A drill stem test was performed in this interval but the well didn't flow
even after the acid job.
LULI-1 well (1990)
- The well drilled to test a thick proven quality Malha/Paleozoic Nubia
sandstone reservoir, as well as several hundred cumulative feet of Rudeis
sands.
- A Miocene sandstone lenses is the primary target, and Eocene/Upper
Cretaceous fractured carbonates and Belayim reefs is the secondary
target.
7 NE OCTOBER & N. ISSRAN
- Luli is a west-dipping NW-trending elongated block which is bounded by
major normal faults on its NE and SW flanks.
- Drilling results showed that the well penetrated 2000' almost a complete
Miocene section excluding Nukhul which was missing. The section was
followed by thick Eocene carbonates and a complete Pre-Miocene section
down to the Nubia sandstone and Um Bogma Formation with no oil or gas
shows in all the horizons.
GI 78-1well (1989)
- This well was intended to test the Rudeis Formation in the downthrown
fault block.
- Shows in a fracture zone in the Brown Limestone were tested with
negative results.
GI 78-2 well (1989)
- The well was drilled to test a possible reefal buildup within a Miocene
platform carbonate sequence.
- Viscous black oil staining was encountered in cuttings and cores from
2490 to 3410 ft depth.
- Sandstones and carbonates in the Rudeis sequence were found to be
water bearing. Minor oil shows were noted in sandstones of the Matulla
and Wata formations.
- Geochemical analysis of oil staining in sidewall cores from the Matulla
Formation detected the presence of migrated hydrocarbons of a
composition and maturity level matching that the relatively high gravity
oil tested in EGB-1 to the east.
- Log analysis indicated intermittent hydrocarbon accumulation in the
Belayim/Kareem, Brown limestone, Matulla, and Wata Formation.
- Reservoir quality was very good in the Nubian sequence, but the
sandstones were saltwater bearing and didn't have hydrocarbon shows.
8 NE OCTOBER & N. ISSRAN
SABIL-1 well (1986)
- The well was drilled on a NW-SE trending fault block dipping to the
northeast. The test was to investigate the hydrocarbon potential of the
thick Miocene sands and the fractured Eocene carbonates.
- The Nubia sandstones and the Upper Cretaceous reservoirs were
considered as secondary targets.
- Significant oil and gas shows were encountered in the Zeit sands and
Belayim, Kareem and Thebes carbonates. High gas readings were also
recorded over the Brown Limestone, Wata carbonates and the entire
Nubia sand section.
- Log evaluation indicated possible pays in the Zeit Formation (30' with
OWC at -2906'), Belayim/Kareem formations (+/- 80'), Thebes formation
(130' with OWC at -6400') and Wata Formation (+/- 110'). The Nubia
sandstones were totally water wet.
- Five drill stem tests were conducted through over the Wata, Brown
Limestone, Thebes, Nukhul and Zeit formations. The fifth test in the Zeit
Formation flowed 225 BOPD, whereas the first four tests flowed salt
water,
- The well was plugged back and suspended as a non-commercial oil well.
C4NA-1 well (1983)
- The well was drilled to test the Cretaceous Matulla sandstone and Nubia
sand sequence of a secondary fault block located on the eastern flank of
a major NNW-SSE trending feature in the central Gulf of Suez.
- One open hole drill stem test was conducted in the Eocene limestone
which displayed good oil shows at interval from 7655' to 7975' and
produced an oil/water mixture with a flow rate of 1 gal/min decreasing to
0.2 gal/min. the poor flow rate is probably due to low fracture
permeability and the absence of effective matrix permeability.
- Hydrocarbons were founded in the Duwi and Thebes formations. In the
Duwi, since permeability is very low and the formation shows the
characteristics of a source rock, it was not likely that can become a good
producing zone.
9 NE OCTOBER & N. ISSRAN
- The Thebes Formation has high hydrocarbon saturation. The sonic data
shows the presence of secondary porosity and the core analysis shows the
presence of fractures. The porosity is good (net pay porosity 20.44%), with
the best porosities (up to 30%) being found at the top of the formation,
however the average permeability is low (net permeability 1.46 mD)
- During the well test, the gravity of the oil was estimated to be 25.5 API,
which is relatively heavy.
- The best porosity of the well is found in the Asl (23.06%) and the best
permeability is found in the Rudeis and Asl Formation (65.36 mD and
201.18 mD). However, no hydrocarbons have been found in these
formations.
- The Eocene oil produced from C4NA-1 is relatively mature marine oil
probably sourced from carbonate rocks deposited under highly reducing
conditions.
EE 81-1 well (1980)
- EE 81-1 was located on a horst block at the eastern edge of a stable
platform which is tilted to the south. The drilling reached to Paleozoic
Nubian Sandstones.
- Minor hydrocarbon shows were reported in the Belayim/Kareem, the
Nukhul, the Matulla and the Wata Formation, whereas the Nubian was
found to be water wet.
- Two DSTs were carried out in the Matulla Formation and recovered heavy
oil (12 API) at a rate of 67 BOPD. An open hole DST in the Thebes
Formation recovered 256 Bbls diesel and salt water, while a DST in the
Belayim/Kareem Fm. recovered minor quantities of black residual oil.
10 NE OCTOBER & N. ISSRAN
Nearby Fields and Wells:
- October oil field (Gupco): The majority of the production and reserves are
found in the Nubia reservoir. The Nazzazat, Nukhul, and Asal reservoirs are
considered secondary targets.
- N. October oil field (Gupco): produced from Nubia-C, Matalla Fm and Asl Mb.
(L. Rudeis).
- N. Amer oil field (GPC): produced from Rudeis & Nukhul fms., Eocene
Limestone Matalla Fm and Nubia sandstone.
- Issran oil field (GPC): the main oil bearing zones are upper & lower dolomite
in Belayim Formation and in Nukhul limestone.
- NW October field (EGPC): Three main reservoirs were tested oil in NWO Field;
they are Lower Miocene (Nukhul Fm.) and Eocene (Mokattam & Thebes Fms).
