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Block 30 - Onshore Oman

SUMMARY

Block 30 is a 1,185 km2 area located in the interior of Oman and straddles the Hajar

Mountains. It is located to the northeast of some of Oman's largest oil fields. Like those fields

the expected reservoirs are within the Wasia and Kahmah groups.

Just to the north/northwest of the block are located Jabals Shams and Akhdar. Extensive

erosion of these mountains has resulted in a breach of the Jabal Akhdar anticline and the

creation of a series of extremely deep wadis cutting through the entire stratigraphic section.

Because of this it is possible to view in detail the three dimensional aspects of what are the

subsurface reservoirs in the portions of the block were gas has been discovered. Thrust faults,

which form a trap type in the block are also visible in outcrop.

Tight gas is the predominant play within Block 30. To date gas has been discovered in the

Natih and Shuaiba formations. These discoveries have not been fully appraised and adjacent

structures remain undrilled. There are currently two additional gas prospects mapped within

the block.

Within the tight gas play is an unconventional sub-play for the Natih E. This unit is a source

interval and also a reservoir. Development of unconventional gas is only beginning in the

Sultanate and the Natih E has been recognized as a prime target.

Six of the nine wells drilled within the block have discovered gas in the Natih or Shuaiba

formations, as well as both of them. Gas rates for DSTs and during long-term tests ranged

from 7 MMscf/d to 18 MMscf/d. These rates may be constrained by drilling-related formation

damage. A clear example of this comes from the Hafar-1 well where the initial test from the

Shuaiba Formation was 1 MMscf/d. Following an acid treatment the production increased to

15.8 MMscf/d.

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BLOCK OWNERSHIP HISTORY

Over its history Block 30 has had many owners and it has also changed configuration. The

primary owners over the years were Petroleum Development (Oman) and Amoco. Other

companies which have owned this block are:

Japex

Gulfstream

Anadarko

RAK

The first well was drilled in 1967 by PD(O): the Hamrat Ad Duru-1. The last well on the block,

the Hamrat Ad Duru-4, was drilled in January 2010 by RAK. The last owner of the block was

DNO, which acquired RAK.

AVAILABLE DATA

Block seismic base map, satellite image map and infrastructure map

950 km 2D seismic data

Gravity data

9 Wells

Seismic and well location base map

STRATIGRAPHY

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Oman chronostratigraphic chart (GTS 2012 dates incorporated)

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The stratigraphic section occurring in this block can be placed into three groups. The oldest

of these ranges from Precambrian to Early Silurian in age and contains the Haima and Huqf

Supergroups. The Amin Formation is part of the Haima Supergroup. No well in the block has

been drilled deeply enough to test this formation but it contains gas in an adjacent block.

Separated by a regional unconformity that removed well over 100 million years of geologic

time is the known pay section. This begins with the Permian age Haushi Group and generally

ends with the Fiqa Formation of the late Cretaceous age Aruma Group. Within this portion of

the stratigraphic section can be found the Natih, Shuaiba and Lekhwair formations, all of

which are regionally significant reservoirs.

Stratigraphy of the Khamah and Wasia Groups in Oman

Finally, overlying the previous portion of the geologic section is the Triassic through Tertiary

age allochthonous section associated with the Hawasina Thrust Complex. This interval is

composed of time-equivalent rocks from over 200 kilometers away. These were thrust over

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the block as a result of Tertiary obduction. This portion of the section is found over much of

the block but is mostly absent in the southernmost region.

OUTCROP AND ANALOGS

The following formations are present in multiple outcrops and can also be viewed regionally

along the modern road to Jabal Akhdar.

Hamrat Duru Group: Allochthonous sediments of the Hawasina Basin

Natih Formation: Reservoir and source

Nahr Umr Formation: Regional seal

Shuaiba Formation: Reservoir

Kharaib Formation: Potential reservoir

Lekhwair Formation: Potential reservoir

DISCOVERIES

Six of the nine wells drilled within the block have discovered gas in the Natih or Shuaiba

formations, as well as both of them. Gas rates for DSTs and during long-term tests ranged

from 7 MMscf/d to 18 MMscf/d. These rates may be constrained by drilling-related formation

damage. A clear example of this comes from the Hafar-1 well where the initial test from the

Shuaiba Formation was 1 MMscf/d. Following an acid treatment the production increased to

15.8 MMscf/d.

PROSPECTS

There are currently two additional gas prospects mapped within the block.

PLAY SUMMARY

Tight gas is the predominant play within Block 30. To date gas has been discovered in the

Natih and Shuaiba formations. These discoveries have not been fully appraised and adjacent

structures remain undrilled.

Within the tight gas play is an unconventional sub-play for the Natih E. This unit is a source

interval and also a reservoir. Development of unconventional gas is only beginning in the

Sultanate and the Natih E has been recognized as a prime target.

TRAP

Predominantly 2-way dip-closed, fault-bounded anticlines. Stratigraphic traps associated with

progradational clinoforms and carbonate platforms exist in adjacent blocks and are expected

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within this block. Although not actively pursued to date imbricate thrusting and fault bend

folding within the Hamrat Duru Group sediments would create traps, although seal is a risk.

NW to SE seismic line that runs parallel to the orientation of the Hawasina Thrust Complex.

RESERVOIR

All potential reservoirs that have been encountered in the block are tight. The carbonate reservoirs

are fractured, which is common in the blocks adjacent to this block. These can be considered

unconventional reservoirs. These are listed below by Group.

Wasia Group

Natih Formation (gas already discovered)

Natih E is an unconventional hydrocarbon target (self-sourced)

Kahmah Group

Shuaiba Formation (gas already discovered)

Kharaib Formation

Lekhwair Formation (strong gas shows)

Haima Supergroup

Amin Formation (Undrilled in Block 30 but gas discovered in an adjacent block)

SEAL

Wasia Group

Natih Formation's more shale-prone members

Nahr Umr

Kahmah Group

Low permeability carbonate mudstones and shales associated with the basal portions of its

formations

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SOURCE

Natih E Formation

Post-Huqf, currently unnamed source

MOVING FORWARD

Proceeding further takes you out of the public area. Doing so gives you access to the raw data as well

as the ability to order interpretation-ready and evaluation packages.

MOG raw data viewing and purchase

This data can be viewed live from anywhere in the world via the MEERA platform.

Acquiring the raw data is simple. These data can be downloaded directly or can be provided

on digital media for a selected destination.

There is a large amount of raw data for this block. These data include seismic lines, well

documents and gravity data. Following is a brief summary listing for seismic and well data.

Seismic data: Results from 15 2D surveys in segy.

CEL93REG1: 1 line

IND07IBI1: 4 lines

IND07IBI2: 20 lines

IND07JAW1: 15 lines

JPX82REG1: 1 line

NOL03BHL1: 3 lines

NOL04BHL1: 3 lines

PDO05REG1: 7 lines

PDO66REG1: 1 line

PDO73REG1: 4 lines

PDO75REG1: 1 line

PDO78REG2: 6 lines

PDO84REG3: 10 lines

PDO87JAW1: 6 lines

PDO98JAW1: 8 lines

Those surveys possessing a high number of lines may contain a smaller number of total lines

which have been processed in several ways.

Well Data: Not all wells contain the same types of data. Most have log data and many have a

series of well documents. Some wells also have core data.

Al Sahwa-1

Hafar-1

Hafar-2

Hamrat Ad Duru-1

Hamrat Ad Duru-2

Hamrat Ad Duru-3

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Hamrat Ad Duru-4

Nadir-1

Nadir-2

Target Oilfield Services’ interpretation-ready package viewing and purchase

Target Oilfield Services has prepared interpretation-ready Petrel and Techlog projects. The

Petrel project contains all seismic data and MOG raw well data. The Techlog project contains

the MOG raw log data.

Both projects will save time since the data management has already been completed. The

data have also been placed into the PSD93 coordinate reference system. Interpretation can

proceed immediately instead of having to wait until the various data have been loaded onto

an interpretation platform.

Target Oilfield Services’ evaluation package viewing and purchase

Target Oilfield Services has completed a comprehensive block interpretation. This

interpretation has rectified data errors and inconsistencies. It places the block within a

regional context and incorporates Target's extensive knowledge of Oman's geology and

reservoirs. Intended to aid in block analysis the evaluation package provides a significant

advantage to anyone trying to assess this block.

The interpretation package for Block 30 contains the following.

A geological evaluation report for the block.

o Reviews and updates/corrects stratigraphy across the block.

o Contains a sedimentological study for the Natih and Shuaiba formations.

o Reviews and provides details on the geologic structures within the block.

o Identifies existing and additional prospects within the block.

Well log data

o Edited, spliced and QC log files for wells

o Interpreted logs for wells

Fault interpretations of the 2D seismic data for the following horizons.

o Natih Formation

o Habshan Formation

Multi-horizon TWT and depth interpretations of the 2D seismic data.

o Natih

o Habshan

Data are in digital format and can be provided as:

o Downloadable data in standard digital formats.

o A complete Petrel project containing the wells, well logs, seismic data and

interpretations.

o A complete Kingdom project containing the wells, well logs, seismic data and

interpretations.

o A complete Techlog project containing the well log data.