Why So Much Oil in the Middle East?

vol. 7, no. 1 – 2010

GEOSCIENCE & TECHNOLOGY EXPLAINED geoexpro.com

Geotourism: The Cape Peninsula

Middle East: Why So Much oil in the Middle East?

Qatar: 70 Years of Oil History

Seismic foldout: West of Shetland

Recent Advances in Technology: Marine Seismic Sources

g e o l o g y g e o p h y s i c s r e s e r v o i r m a n a g e m e n t Next edition of GEO ExPro; March 2010: Kurdistan: Safe and Secure, with Billion Barrel Prospects Photo: Halfdan Carstens GEOSCIENCE & TECHNOLOGY EXPLAINED columns 5 Editorial 8 ExPro Update 16 A Minute to Read 32 Recent Advances in Technology: Marine Seismic Sources 20 42 History of oil: Qatar Why so Much Oil in the Middle East 48 Geotourism In terms of oil reserves, the Middle East is second to none. This “oil miracle” 54 Energy Statistics: Provided by Rystad Energy of the world has been shaped by a set of favourable factors, some global 56 Geomedia: Edwin Drake and others local, inscribed in the geologic history of the region. Here we see 58 Global Exploration Update the oil museum in Muscat, Oman. 60 Q&A 62 Hot Spot 64 Global Resource Management: Iraq Illustration: TGS features 20 Why so Much Oil in the Middle East

28 The First Oil Discoveries in the 36 Middle East 36 SEISMIC FOLDOUT: GEOSCIENCE EXPLAINED: Seismic Fold-out IMPROVED SUB–BASALT IMAGING Newly reprocessed long offset seismic data from the Faroe Shetland Basin now provides a tool to enable interpreters to produce meaningful correlation in the sub-basalt section and raises some exciting geological questions for the West of Shetlands.

54 36 60 8 6

1 64 59 62 20 28 42 58

59 48 GEOSCIENCE & TECHNOLOGY EXPLAINED iraq’s overwhelming problems www.geoexpro.com Roughly 60 percent of the world’s oil reserves and 41 percent of the world’s gas reserves belong to Middle Eastern countries. Some of that - actually, quite a bit - rests in the Iraqi subsurface. According to the BP Sta- GeoPublishing Ltd 15 Palace Place Mansion tistical Review of World Energy (2009), Iraq’s estimated oil reserves are now 115Bb, only surpassed by Saudi Kensington Court Arabia and Iran on a world-wide basis. Others present figures that are even higher. The result is the same. By London w8 5bb, u.k. making these barrels available to the world, as is now being done by Baghdad officials, production may soar +44 20 7937 2224 from 2.5MMbopd today to more than 10MMbopd in 2017. That, at least, is the ambitious government target. When Iraq was invaded in the spring of Managing Director Tore Karlsson 2003, many believed that the war “was merely a grab by Western com- Middle Middle East East Editor in Chief panies for Iraq’s vast oil reserves” Halfdan Carstens (TIME, December 7, 2009). If so, they have certainly succeeded in Contributing Editors their efforts. Following two Thomas Smith [email protected] licensing rounds last year, altogether ten Middle East oil and gas reserves Jane Whaley contract areas have compared to the rest of the world’s [email protected] been awarded. And, if reserves. Oil in green, gas in red. the companies succeed Rasoul Sorkhabi [email protected] in their efforts, production may eventually reach the official Paul Wood target, or even more. [email protected] In fact, the projected increase will boost global output and may eventually bring down oil Editorial enquiries prices. GeoPublishing 7491 Trondheim, Norway The bad news is that the war-torn country has lost most of its infrastructure. What was there when produc- +47 73 90 40 90 /+47 90 56 35 95 tion peaked at 3.7MMbopd in 1979 is now largely gone. Their almost insurmountable problems also include [email protected] brain drain, meaning that there will be a critical shortage of geologists, geophysicists, engineers and managers. www.geoexpro.com Unlike their neighbours Saudi Arabia, Kuwait and Iran, experts need to be imported into the country in order to achieve the goals. Marketing Manager Thanks to Saddam Hussein’s behaviour, the timely invasion of Iraq seven years ago and the new govern- Kirsti Karlsson +44 79 0991 5513 ment’s need for technical and financial investments, the huge deposits of oil and gas in Iraq are now again [email protected] available to assist international oil companies to book new reserves. Subscription GeoPublishing Ltd +44 20 7937 2224 15 Palace Place Mansion Kensington Court London w8 5bb, u.k. [email protected] Halfdan Carstens Editor in Chief geo expro is published bimonthly for a base subscription rate of gbp 50.- a year (6 issues). We encourage readers to alert us to news for possible publica-

VOL. 7, NO. 1 – 2010 THE MIDDLE EAST “OIL MIRACLE” tion and to submit articles for

HNOLOGY EXPLAINED GEOSCIENCE & TEC The Middle East is unique when we look into why the Middle publication. geoexpro.com it comes to petroleum reserves. As East is flush with oil and gas. Geotourism: The Cape Peninsula shown in the graph above, roughly As explained in our Cover Story, Cover Illustration: Drilling for oil in the Middle East. 60% of the world’s oil reserves are it has to do with both regional Photo: Halfdan Carstens Middle East: found beneath vast, inhospitable and global factors, meaning that Why So Much oil Geotourism photo: in the Middle East? deserts with little else to offer. the long story begins in the late Jane Whaley Qatar: Sheep feeding on almost barren Precambrian. And, as every pe- 70 Years of Oil History

Seismic foldout: rocks is nevertheless a familiar troleum geologist knows, it has West of Shetland Layout: Skipnes Kommunikasjon

Recent Advances in Technology: sight in some areas. In this par- to do with source rocks, reservoir Marine Seismic Sources Print: NXT Oslo Reklamebyrå

R E S E R V O I R M A N A G E M E N T ticular case, in Syria, they have rocks and cap rocks. In addition, G E O P H Y S I C S G E O L O G Y found a sweet-spot close to a rig a favourable time relationship issn 1744-8743 drilling for oil. between migration and trap for- In this edition of GEO ExPro mation is needed.

geo expro february 2010 5 Jane Whaley ExPro Update

Life in the UKCS yet? ABBREVIATIONS Numbers Drilling activity on the UKCS the 26th UKCS Seaward Westward LLP gave an inter- (U.S. and scientific community) fell dramatically in 2009. Well Licence Round, expected early esting overview of the oppor- M: thousand = 1 x 103 numbers were on a par with in 2010. tunities available in the UKCS, 6 2005 - and only 7% were ex- As Simon Toole from DECC emphasising the fact that more MM: million = 1 x 10 9 ploration wells – but the mood said in his opening address, there than 500 prospects with an B: billion = 1 x 10 at the seventh Prospect Fair, is still an estimated 20 Bbo in average size of 44 MMboe have T: trillion = 1 x 1012 PROSPEX, in December 2009 the UKCS waiting to be found. already been identified but not was distinctly one of cautious Although some of the smaller developed in the area. Extrapo- optimism. players appeared to be suffer- lating from previous rounds, Liquids PROSPEX, sponsored jointly ing as a result of the economic he anticipates that this new barrel = bbl = 159 litre by the PESGB and DECC, was downturn, he pointed out that round should attract about 20 boe: barrels of oil equivalent held in the Business Design more than 400 MMboe per year well commitments and see the bopd: barrels (bbls) of oil per day Centre in London, and attracted were discovered between 2007 awarding of about 250 blocks. bcpd: bbls of condensate per day more than 700 delegates, 73 ex- and 2009, with the Promote Ini- Delegates at the conference hibitors and 24 talks. It showed tiative alone leading to 18 pub- commented on the generally bwpd: bbls of water per day that, despite the economic lished successes. He said that the buoyant and optimistic mood. climate, there is still plenty of 26th Licence Round may intro- One exhibitor even complained Gas interest in North West Europe duce a new nine year West of that the first day was too MMscfg: million ft3 gas and the UKCS in particular. The Shetland frontier licence, as well crowded! Signs that the industry 3 year actually saw an increase in as fresh acreage in the underex- has not yet finished with the MMscmg: million m gas exploration activity in the chal- plored Western Approaches and UKCS yet, perhaps? Tcfg: trillion cubic feet of gas lenging areas West of Shetland, English Channel. and there was much talk about Chris Bulley from Hannon Ma: Million years ago

LNG Liquified Natural Gas (LNG) is natural gas (primarily methane) cooled to a temperature of approximately -260 oC.

NGL Natural gas liquids (NGL) include propane, butane, pentane, hexane and heptane, but not methane and ethane.

Photo: kmphotos.com/PESGB Reserves and resources P1 reserves: Quantity of hydrocarbons believed recoverable with a 90% probability

P2 reserves: Quantity of hydrocarbons believed recoverable with a 50% probability

P3 reserves: Quantity of hydrocarbons believed recoverable with a 10% probability

PROSPEX, held in London in December 2009, has developed into a major event for those active in the North Sea. Oilfield glossary: www.glossary.oilfield.slb.com

6 geo expro february 2010 Technology Update Jane Whaley

Geologging on the Forties Field

Aberdeen based HRH Geological Services has spent many years helping companies find the right technology to unlock the potential of their fields by turning geological data into more useful digital formats which can be integrated into the workflow. Its innovative Geologging service is the latest technique to assist in this.

“Geologging improves workflow and connectivity between the rig site and the office,” explains HRH’s Managing Director David Harrison. “The onboard Geologgers, all fully qualified and trained geologists, use our

Gravitas software to turn the Image: HRH Geological Services geology into logs, charts and reports, which link into the platform’s incumbent drilling monitoring package and connect the asset to the digital oilfield. The key value of the software lies in the number of ways that it collects data from different rig vendors. This is then produced in various formats, each one allowing different key rig personnel to use it to improve their assumptions while drilling. The software provides all sorts of different reporting methods throughout each stage of the well life cycle, from the planning operational stages to the con- tinuing and final analyses.” HRH Geologgers are trained to a significantly higher level than conventional mudlogging personnel, frequently being deployed as wellsite geologists in their own right. “The Geologging service also means that there is no longer a need to process cuttings offshore, as the cuttings samples mated five billion barrels of oil the detailed core investigations data for a bit of extra room, but are dried, stored and analysed in place, but when Apache took are undertaken onshore, the the data our systems are supply- onshore at our premises in it over in 2003, production was geologgers have more time for ing is as good as, if not better Aberdeen. This halves the down to 35,000bpd, compared geological interpretation, with than, the traditional methods.” number of mudloggers needed to its peak of 500,000bpd in the the Gravitas software ensuring “We are happy to know that on a rig from four to two, sig- late Seventies. that information flows rapidly our Geologging service has nificantly reducing costs and “Apache knew that reducing to the decision makers in almost been a vital contribution to the space.” the number of people on board real-time.” renewed success of the Forties This change of conventional was key to success,” David “Initially, Apache had reser- field,” David Harrison con- workflow caught the interest of explains. “Until 2006, the vations as to whether by using cludes. “In the three years since oil company Apache North Sea, Forties field had operated with such a reduced team there we started working there, 70 specialist in field rejuvenation, conventional mudlogging teams would be a consequent reduc- wells have been drilled, and pro- when Apache was analysing of four to six people. HRH tion in quality of interpretation duction has doubled to approxi- ways to improve production at replaced this with our Geolog- and analysis, but we are pleased mately 70,000 bpd. Geolog- its new acquisition, the legend- ging service, which requires to say that this fear has been ging has freed up rig space and ary Forties field. Found in 1970, only two people working back proved completely unfounded. reduced head count, cut costs Forties is still the largest ever to back on 12 hour shifts, Oil companies would not com- and delivered a better service. A UKCS discovery, with an esti- freeing up platform space. Since promise the quality of geological win-win situation!”

8 geo expro february 2010 Technology Update Jane Whaley

World Leaders in Thermal History

What is Apatite Fission Track Analysis – and how can it help the oil industry?

“We use a technique called the UK and the Recôncavo Basin “Apatite Fission Track Apatite Fission Track Analysis of Brazil, have been found to Analysis is therefore based on (AFTA®), in tandem with other contain significant quantities of measuring fission track age and methods, to determine the hydrocarbons. In these areas, dis- length and the chlorine content thermal history of rocks and, in covering hydrocarbons requires of each grain, and modelling Photo: Jane Whaley particular, to identify when a rock detailed knowledge of the mag- these parameters to determine section cooled from its maximum nitude and timing of exhumation the most likely thermal history post-depositional temperature,” and its associated effects. scenarios.” explains Paul Green, Technical This is where Australian Multiple cooling episodes can Director of Geotrack Interna- company Geotrack International often be resolved from data in tional, the only company in the comes in. individual samples. “This sort of world to specialise in this tech- information cannot be obtained nique. The method from any other source, and we “We analyse ‘fission tracks’ can therefore provide unique Need for knowledge within detrital apatite (a phos- constraints on when hydrocarbon Most oil and gas is found in basins phate mineral) grains extracted generation effectively ‘switched with relatively simple histories, from sandstones and other clastic off ’,” Paul continues. Dr Paul Green, together with Dr. where source rocks have under- rocks. Each track is created by “By combining this data with Ian Duddy, founded Geotrack gone almost continual burial to radiation damage resulting from structural information, it is International in 1986 to enable reach the temperatures required spontaneous fission of a single possible to identify areas where AFTA to become a routine tool in 238 the hydrocarbon industry. to generate hydrocarbons. atom of uranium ( U), and the hydrocarbons were generated But in some regions, rocks number of tracks in an apatite after traps were formed, which have been exhumed from their grain depends on uranium can significantly reduce explora- maximum burial depths to shal- content and time. Therefore, by tion risk.” lower levels. These areas are measuring the amount of 238U Africa have been high and stable conventionally viewed as less and number of tracks, we can Burial histories since the rifting of the conti- attractive for exploration, as calculate the time over which revealed nent that led to formation of the seal may have breached, and the the tracks have accumulated. This technique has revealed margins. But our AFTA data timing of hydrocarbon genera- However, the length of tracks is hidden complex burial histories, shows this is not the case, and the tion is also more difficult to re- reduced by burial, as tempera- showing that areas which had landscapes are much younger. We construct because some geologi- ture increases the speed at which previously been thought to have have studied this phenomenon in cal section is missing. However, the radiation damage is repaired, experienced either prolonged sta- Namibia, SE Australia, Green- many exhumed basins, such as which is also affected by the bility or more or less continuous land and Brazil.” the Southern North Sea Basin of chorine content.” subsidence have in fact undergone Geotrack International formed major episodes of exhumation. out of a research group at the “AFTA often exposes accepted University of Melbourne in geological histories to question,” the 1980’s, in order to provide Paul adds. “For example, we thermal history reconstruction to have discovered a remarkable the oil exploration industry. Spe- coincidence in the timing of cialising in AFTA and support- major phases of exhumation ing techniques like vitrinite re- from Alaska and Arctic Canada, flectance, it also provides services through Greenland into Norway such as petrographic analysis and and through the North Atlantic microanalytical methods. Over to the UK. We found that these 1,000 studies have been success- phases of exhumation coincide fully conducted throughout the with times of major regional rear- world, covering a range of geo- rangements of the tectonic plates logical settings, including thrust throughout the Arctic and North belts, foreland basins, inverted Atlantic regions, which cannot be basins, intra-cratonic settings and explained by current theories.” rifted margins. Image: Geotrack International “Similarly, it is often assumed This apatite crystal shows etched tracks caused by radiation damage result- that the 2,000m high plateaus ® AFTA is the registered trademark ing from spontaneous fission of a single atom of uranium. seen in places like Southern of Geotrack International

10 geo expro february 2010 Technology Update r dsge fr aaes with managers, for designed are montage page back the and page initial The criteria. search porate cor their against it match and easy for them to evaluate an asset Mike continues. idea is to make it “The quickly,” need they tion informa the find to where and expect,to what know clients our always follow the same format, so ourclients.”for target and contact the right people montage,of style unique then and its including format, recognised it succinctly and visually in Envoi’s potential in an asset, to summarise offer is to be able torapidly see the we skill “The purchasers. spective pro for looking and assets area non-core of themselves divest to to partners spread exploration risk, or wishing seeking either me to come “Companies laughs. he really!”match-maker, a as act “to panies themselves. com the by done generally was sellers together, which at the time and buyers potential putting and deals farmout international ing market a in specialising company for need specific a saw soon He marketing. to inter project national exposed first was he where Petresearch, joined Mike Kelt, then and geolo Carless with a gist as industry oil the in working years of number a After you andyourexpertise.” andtobelievein isoffering, with peopleandgettingthemtoquicklyunderstandwhatanopportunity explains MikeLakin,founderandManagingDirectorofEnvoi.“You mustbegoodatcommunicating “You needaknowledgeofpsychologyinthisjob,tounderstandhowandwhypeopledodeals,” ofGeology The Art 12 “Envoi’s project synopses synopses project “Envoi’s Mike established Envoi in 1999 geo expro february geo 2010 GEO ExPro 2 0 0 4 - 2 0 0 9 Previous issues: y g o l o e g

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Photo: Gillianne Tedder GEOSCIENCE & TECHNOLOGY EXPLAINED TECHNOLOGY & GEOSCIENCE S C I S Y H P O E G

R I O V R E S E R

Photo: APOC

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Northern Explorer Northern Hawk Explorer seismic source vessels and 4C/4D seabed node seismic seismic streamer, node seabed services. long-offset acquisition data 4C/4D and 2D vessels 3D, source seismic shallow streamer in towed specializing water contractor, multi-disciplinary acquisition world-wide a seismic is Exploration SeaBird Node Operations vesselNode Explorer |Hugin R I O V R E S E R - - Osprey Explorer Munin Explorer Munin 2D Long Offset - Source-2D-3D Vessels -Source-2D-3D Offset 2D Long

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30/9/09 12:19:15 GEO EXPRO VOL. 6, NO. 6 – 2009 – 6 NO. 6, VOL. EXPRO GEO Y G O L O E G Waters Icy for Preparing vessels: Seismic Gabon Offshore Pre-salt foldout: Seismic gas and oil all of 90% generated has horizons Six Rocks: Source geoexpro.com

GEOSCIENCE & TECHNOLOGY EXPLAINED TECHNOLOGY & GEOSCIENCE S C I S Y H P O E G

Jane Whaley R I O V R E S E R

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Market Update

Thina Margrethe Saltvedt (Ph.D.) Senior macro/oil analyst at Nordea Markets, Oslo, Norway major events geologic time scale

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N Tertiary oic the Agenda in the Oil Market z 2323 ening

Oil prices are expected to rise gradually in 2010 and accelerate en o C at the end of 2011 as as the world economy gradually strengthens gene ts o p ale o

and the oil fundamental balance tightens. P 65 y 65* tic sta r ge n ening The demand for oil is sensitive Increasing investments are y

o Cretaceous to global economic cycles. The also needed to expand capacity tla n ge n ts o p global economy is now gradually to meet the world’s growing need o lpine o r outh A S recovering and industrial produc- for energy. High costs, the finan- A

tion is picking up pace. Robust cial crisis and global recession ea sta r growth in oil-intensive emerging have put adequate investments in amide o r a r 145145 L eakup

economies is expected to be a key new capacity at risk. oic z Jurassic driver of oil demand. Urbanisa- Timely investments in the eenland S r tion and increasing living stan- Middle East are essential as a es o M ting dards, especially in countries with growing share of the future oil angaea b r i f P

large populations such as China production is expected to take egian- G w ea r ts and India, are expected to accel- place in this region. The region o r 199199* ening N th S

erate the demand for energy and has around 60% of the world’s e n o r

Triassic v N continue to boost car sales. proven oil reserves. Last year’s ts o p Transport fuel is expected licensing rounds for Iraqi oil

to increase its share of total oil fields have increased the capacity tion E tic sta r 251251* consumption. Although the Co- potential in the medium term. tla n

ting Permian penhagen Accord was weaker But the obstacles to invest are tin c oic i f oic z z al A o o than expected, we still anticipate many such as sovereignty over oil o r t r e E x xi c binding deals on climate gas reserves, increasing national pro- e n i v e C 299299 hane r emissions to be signed within tectionism and political unrest. hane r P the forecast period. In the long Aggravating the risk of inade- P Carboniferous

term, binding requirements for quate investments to meet future ulf of M G ANGAEA emission cuts are expected to supply requirements is the unfa- he Big F T

gradually change the framework vourable investment climate in * for the total energy spectrum. other oil regions such as Nigeria, TION OF P 359359* As oil demand now gradually Venezuela and Russia. Russian recovers, the market will soon oil production increased, sur- Devonian FORM A oic oic z shift its focus back to a world prisingly, in 2009 after peaking z that is running out of accessible for the second time in 2007. ale o ale o P oil. Production is now falling at However, the upside potential P y 6.4% per year from old mature is limited without further tax 416416 oil fields. Huge investments cuts. Limited access to investing ge n o Silurian are thus necessary just to offset in areas with larger reserves at

an o r 443443* losses from steep production falls lower costs forces oil companies y

in areas such as the North Sea, to invest in higher cost areas, is c Ordovician ge n a r o Alaska, the Mexican Cantarell which also contribute to higher V field and West Siberia in Russia. prices. 488488 aledonian o r

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The Great Unconformity 542542 oic oic z z ian ian o o e r e r o t o t amb r amb r e c e c r r eop r P eop r Source: Nordea Markets P N N Oil price scenarios - baseline, high and low price for the period 2002-2011.

14 geo expro february 2010 A Minute to Read News around the world

More data offshore U.S. East Coast More data in the Gulf Spectrum has accelerated its In 2006, the company submit- CGGVeritas has begun acquir- uled for August 2010. Final preparations to collect seismic ted permit applications to the ing the Three Corners Exten- products from the survey are data in the U.S waters of the Minerals Management Service sion 3D Wide-Azimuth multi- expected to be delivered in the Atlantic Ocean in response to (MMS) to conduct seismic, client survey in the western second quarter of 2011. the recent announcement by the gravity and magnetic surveys Gulf of Mexico. The 415-OCS According to Colin Murdoch, Department of the Interior to off the US East Coast. The block wide-azimuth survey is an Executive Vice President, North begin the environmental analysis new survey would extend Spec- extension of the recently com- America region, CGGVeritas, of geological and geophysical ac- trum’s U.S multi-client library, pleted Three Corners Wide- the customers have been im- tivities off the east coast. which has been growing since Azimuth survey. The combined pressed with the preliminary Spectrum was the first the company began acquisi- survey will cover over 600 blocks image results from the Three company to actively collect tion offshore Florida in 2003. in East Breaks and Alaminos Corners survey. “Until now multi-client seismic data since This modern seismic now covers Canyon. the Alaminos Canyon protrac- the leasing and drilling mora- much of the “un-leased” area of Acquisition is scheduled to tion area has been one of the torium went into effect in the Eastern Gulf of Mexico. be completed during the second most difficult areas to image mid-1980s. It is currently re- Upon receiving permit ap- quarter of 2010, enabling the in the Gulf of Mexico, yet our processing and studying existing provals, Spectrum plans to delivery of a Fast Trax 3D wide-azimuth acquisition and seismic data from the U.S East actively pursue a comprehensive PSDM RTM volume to the advanced imaging technologies Coast. Through these activities, program to acquire seismic and industry prior to MMS OCS have shown excellent results,” Spectrum is gaining knowledge other geophysical data over the Western lease sale 215 sched- Murdoch says. to identify the most prospective U.S Atlantic offshore continen- areas for oil and gas explora- tal shelf and deepwater areas tion and the technologies to best focusing its activities with the image and understand the sub- knowledge gained from the re- surface in this frontier region. processed data.

More data in Indonesia TGS has launched a 2D seismic The program has industry acquisition program offshore pre-funding and supports the West Papua in East Indonesia. Indonesia government’s overall The program adds 2,240 km of objective to attract exploration new 2D data designed to help and raise declining production evaluate the petroleum potential levels. © CGG south of the Salawati Basin. The Upon the completion of the Salawati Basin is recognised as program, the TGS Indonesia one of the largest oil basins in library will exceed 100,000 ki- More data in Liberia Eastern Indonesia with total cu- lometers of 2D seismic; 400,000 mulative oil production of more kilometers of multi-beam bathy- TGS has commenced acquisi- the Africa Transform Margin. than 300 million barrels. metric data and 1,200 core tion of the next phase of 3D Recent petroleum discoveries in Data acquisition is now underway samples covering over 1 million projects offshore Liberia. This the Gulf of Guinea and offshore and is expected to conclude by square kilometers of Indonesia’s newest project covers Liberia Sierra Leone have attracted sig- the second quarter of 2010. deep-water basins. blocks 8 and 9 and totals 5,000 nificant exploration interest in km2. The MV Polarcus Nadia this region. Upon completion of will acquire the project and this latest project, TGS will have TGS will apply advanced pre- more than 30,000 kms of 2D and stack time and pre-stack depth 18,000 km2 3D seismic covering imaging techniques to create the this emerging exploration play in final subsurface image. West Africa. The TGS African data library The acquisition of the survey includes a series of 2D and will complete in Q2 2010 and is

Arctic Energy, Tromsø, Norway, May 31-June 4, 2010 The Arctic Energy is a forum for presenting recent developments in the geological research, exploration and exploitation of petroleum resources in the Arctic and for discussing future challenges. The conference aims at participants from the petroleum industries, academia, governmental institutions, consultants and service companies.

16 geo expro february 2010 cyprus_megaproject_geoexpro_0210_version2 29/01/2010 10:48 Page 1

A Minute to Read News around the world

3D in Saudi waters More accurate MWD ARGAS, a Saudi Arabian joint initial 6,000 sq km over the Fugro Gravity & Magnetic Geomagnetic referencing is venture owned 49% by CG- next three years and require Services has introduced its Mag- frequently used by leading drilling GVeritas and 51% by TAQA, has operational expertise working CUBETM technology, which companies. When enhanced by been awarded two major Ocean in complex environments, such enhances geomagnetic referenc- MagCUBE, it can lead to signifi- Bottom Cable (OBC) 3D data as producing oil fields and busy ing by increasing the accuracy cant savings in overall project costs CYPRUS acquisition contracts by Saudi shipping lanes within the Saudi of measurement while drilling by providing accurate, real-time Aramco. The two contracts have waters of the Gulf with depths (MWD) in directional drilling data on well position while correc- a combined value of around $375 ranging from 20 to 60 meters. applications. tions to trajectory are still possible, million. ARGAS will mobilize two MagCUBE utilizes the minimizing the need to side track; The first project is scheduled fully independent OBC crews magnetic intensity measured and minimizing the costs of extra MC3D Data to start in June 2010 and operate equipped with the latest Sercel at the surface from an airborne, rig time required to run a post- Offshore Cyprus for a period of 18 months while SeaRay 4C equipment and re- marine or land magnetic survey. drilled gyroscopic survey. and Lebanon the second is scheduled to run cording systems. These fully The surface magnetic data is geo- from October 2010 for a period offshore operations will be magnetically referenced to the of 24 months; each contract managed through a fleet of magnetic survey data measured respectively has an 18- and vessels equipped with CGGVer- in the wellbore to provide a finer LEBANONLEBANON 24-month optional extension itas deployment and positioning subsurface anomaly vector, which period. systems geared to operate in such provides a more accurate well The projects will cover an environments. path to avoid costly side tracks. © Fugro Gravity & Magnetic Services Magnetic & Gravity Fugro ©

ERGO: It’s logical called ERGO. Web-delivered via a Wiki™- lected, describing sandbody and To optimise modern reservoir based front-end, it provides easy geomorphic reservoir elements in Fugro Robertson’s 40 years of ex- modelling techniques, it is impor- access to the geometry database Fluvial/Alluvial and Deep Water perience in sedimentology and tant to understand the geological and the tools to investigate it environments, with innovative at- reservoir characterisation has led controls on reservoir formation. Key functionality includes the tribution derived from in-house to the development of a new tool However, modellers often under- ability to easily calculate inputs datasets such as Tellus™, Plate designed to help decision-making estimate the value of geological for modelling software by using Wizard™ and Merlin™. in static reservoir modelling. It’s analogues, and good quantitative simple statistical and charting Already a well-proven tool, and descriptive data for reservoir tools that enable the user to un- ERGO is being expanded to cover geometries is not always easily derstand and apply relationships the full range of depositional en- MegaSurveys Eastern Mediterranean MegaProject Phase 1 available. ERGO bridges that gap, derived from analogue datasets. vironments. The eventual goal offering a great source of input data ERGO data sources include is to develop ERGO so that it is (quantitative reservoir geometries) public domain literature, remote capable of generating quantitative combined with an expert knowl- sensing datasets and targeted data that describe geological ana- edgebase of depositional processes fieldwork. 11,000+ detailed res- logues for all modelling and explo- and reservoir modelling methods. ervoir geometries have been col- ration scenarios. The Eastern Mediterranean MegaProject (EMMP) Phase I comprises of more than 30,000 km of GeoStreamer® and Improving subsalt the mega 3D seismic program streamers and the fact that, with areas, known as Han Sur-Oeste conventional 2D seismic data, matched and merged with 3,000 imaging currently being acquired for a 12 by 8-km by 100-m configu- de Tamil, covers a surface area of PEMEX in the Gulf of Mexico. ration, the Alizé is towing one of 12,300 km2 in the Mexican deep sq.km of 3D data offshore Cyprus and Lebanon. Regional horizons, CGGVeritas says that the suc- Despite severe winter weather the largest areal receiver arrays in waters of the Gulf of Mexico. several of which are beneath the Messinian salt, have been cessful deployment of its Nautilus conditions the Alizé, on its first the industry. Robert Brunck, Chairman Regional interpretation acoustic positioning and streamer project of the program, has Nautilus has dramatically and CEO, CGGVeritas, claims interpreted to provide a better understanding of regional plays and steering system on the Alizé, achieved a one-day production reduced the infill requirements that the Alizé’s deployment of a GeoStreamer data hydrocarbon prospectivity. one of its high-end vessels, has record of 117 km2 and has sig- through consistent streamer sep- combination of advanced Sercel dramatically increased produc- nificantly exceeded production arations and depth control across Sentinel solid streamers and Subsalt horizons tion levels on the first project of targets. This has been supported the entire spread. Nautilus is setting a new bench- The EMMP Phase I offers a head start before opening of by the deployment of 12 Sercel The first project in the PEMEX mark for safer operations, quieter Upcoming license rounds license rounds in 2010. Exclusively provided by PGS.

NO. 5 – 2009 VOL. 6, Nautilus-Sentinel® steered solid survey program targeting subsalt data and better crew efficiency.

Y EXPLAINED

GEOSCIENCE & TECHNOLOG

geoexpro.com Geotourism: Great Water australia: The seismic data base constitutes open fi le 2D and 3D seismic data that have recentl reprocessed, together with the acquisitioy been High Resolution Aeromagnetic (HRAM) surveyn of and Synthetic Aperture Radar (SAR) seep data. The 2D seismic reprocessing includes spec Examples of trap ty pes in the Ceduna Su ial b-basin. new study reveals Amplitude Variation with Offset (AVO) produ Early Cretaceous san ds are orientated in tilte cts blocks and basement dr d fault for more advanced analysis. Only two wells apes along the basin m have been drilled. gin. The Upper Cretac ar- eous plays are largely con- fi ned to the deeper aterw area, in tilted faul and horsts where the t blocks Reservoir Management: sealing potential is h ighest. Based on an entirely new data set, including reprocessed seism Younger Turonian fan plays draped ov huge potential thrust along the sou er the toe thern margin represent ic and remote sensing data, a new, an integrated geological study clearly demonstrates the as yet unrecognised play in the basin. Whi structuring is comple le the The Importance of presence of mature source rocks x along this outer f old trend, and a multitude of play models in the Ceduna Sub-basin off s and may ultimately require 3D coverage, th deep seated and the in e thrust is 4D in IOR GEO ExPro 2010 version has generated See full story starting on p hore Southern Australia. area closures. large age 39. Image: FMCS and MCG Section Width ~ 170 kms Submarine Channel Image: FMCS and MCG Turonian Source Rocks History of Oil/ Turonian Fan Amplitude Anomaly Recent Advances in Technology: The Valhall Story Six editions. Six seismic foldouts. Per Helge Semb Oystein Lie Nicolai Benjamin Dahl Tel: +47 90 61 99 61 Tel: +47 93 08 56 61 Tel: +47 92 49 39 31 A Clearer Image

LEGEND Present Day [email protected] [email protected] [email protected] MANAGEMENT Top Paleocene www.pgs.com RESERVOIR Top Santonian GEOPHYSICS Intra Coniacian GEOLOGY Top Cenomanian Base Cenomanian Intra Aptian 36 geo expro october 2009 Basement

Data courtesy of and

Illustration: Fugro

geo expro october 2009 18 geo expro february 2010 38 Gas Oil TOPIC GEOSCIENCE E X P L A I N E D

Why So Much Oil in the Middle

20 geo expro february 2010 TOPIC GEOSCIENCE E X P L A I N E D

In terms of oil reserves, the Middle East is second to none. This “oil miracle” of the world has been shaped by a set of favorable factors, some global and others local, inscribed in the geologic history of the region.

rasoul sorkhabi, ph.d.

The term “Middle East” is not without problems. First, it has colonial connotations, as the term first appeared in the mid-nineteenth century as part of the Europe-centered division of the East into the Near, Middle and Far East. Second, there is no consensus on the geographic extent of the Middle East. Some define it as the region between India and Egypt, in which case it has been aptly designated by the United Nations as Western Asia. Other definitions also add North Africa or central Asia. For the purpose of this article, the term “Middle East” focuses on the oil-rich countries in southwest Asia including Iran, Iraq, Syria, Kuwait, Saudi Arabia, Bahrain, Qatar, United Arab Emirates (UAE), Oman, and Yemen. These ten countries together have an area of 5.1 million square kilometers or about 3.4% of Earth’s land surface, but they possess 60% of world’s known oil reserves and 41% of natural gas reserves. From time to time, regions such as the Caspian or West Africa have been fantasized as “another Middle East” but none has materialized, which begs this important question: Why is there so much oil in the Middle East? This article synthesizes our knowledge about this question and briefly describes the geological factors for the abundance of oil in the Middle East. gondwana margin and tethys The Proterozoic-Cambrian transition at 542 Ma opened a new chapter in the geologic history of the Middle East with far-reaching implications for petroleum resources of this region. After a long history of ocean subduction and micro-continental collision along the northeastern margin of Africa, from about 700 Ma to 600 Ma, the basement rock of the Middle East (the Nubian-Arabian shield) was consolidated. This event, together with some other collisions as- sembled the supercontinent of Gondwana in the southern hemisphere, comprised by Africa, India, Australia, Antarctica, and South America. The Middle East was then positioned on the north-facing passive margin of Gondwana. Throughout Paleozoic and Mesozoic times, the Middle East was a locus of sedimentation over a long and wide shelf affected, from time to time, by sea level changes. As Gondwana consolidated at the turn of the Cambrian, mi- croorganisms and marine species also rapidly evolved and diversified, thus enriching marine sediments with organic carbon necessary for oil generation. The Tethys Ocean, which washed the northern margin of Gondwana, was not asingle ocean, but developed in at least three oceanic basins: Proto-Tethys (Infracambrian-Carbonif- erous), Paleo-Tethys (Ordovician-Early Jurassic), and Neo-Tethys (Permian-Paleocene). This Why So Much Oil in the Middle East?

geo expro february 2010 21 TOPIC GEOSCIENCE EXPLAINED

40°E 50°E 60°E 40°N sequential development of Tethys took place as continental fragments successively broke 0 300 km Caspian away from the Gondwana margin and drifted 0 300 miles Sea northward to join the paleo-Asian continent.

S Y R I A The opening of each Tethys ocean was ac- companied by extensional tectonics which, in I R A N turn, created continental rifts during the In- I R A Q fracambrian (Ediacaran-Cambrian transition ° 30 N period), the Ordovician, and the Permian in Persian the Middle East. These rift basins added fa- KUWAIT vorable sites for petroleum generation in the Gulf region. BAHRAIN Of the Earth’s total land Gulf of Oman At the end of the Paleozoic, Gondwana S A U D I surface (149 million Red Sea QATAR U A E A R A B I A square kilometers), ten merged with Laurasia to form the largest su- O M A N countries in the Middle percontinent ever, Pangea. It was also during 20°N East account for only this time that Proto-Tethys closed and Neo- 3.4% of the area but Tethys began opening. In the Late Creta- contain 60% of world’s ceous, Neo-Tethys began to subduct beneath O I L G A S known oil reserves and 41% 41% of natural gas the southern margin of paleo-Asia (along the 40% Y E M E N Middle East reserves. Despite de- Anatolia-Iran-Tibet margin) and shrank in Rest of World 59% 2681 tcf cades of exploration 504 bbl 60% Rest of World size until the ocean completely disappeared in Middle East worldwide, we have not Gulf of Aden 3853 tcf the Eocene and gave way to a foreland basin 754 bbl found “another Middle East.” in front of the rising Bitlis-Zagros-Himala- 10°N yan mountains. Illustration: Rasoul Sorkhabi Rasoul Sorkhabi (2009)

30°E 40°E 50° E 60°E N

° BITLIS CASPIAN 40 ANATOLIAN PLATEAU SEA

Zagros foreland sediemnts 1.4 cm/yr ZAGROS SUTURE Tectonic framework of the Middle East di- Zagros folded belt MEDITERRANEAN ASIAN PLATE vided into (1) Zagros fold-and-thrust belt, (2) SEA 1.9 cm/yr Unstable Arabian shelf, and (3) Stable Ara- IRANIAN bian shelf. The Arabian continental plate, LEVANT FAULT

PLATEAU which collided with the Asian plate along the N

° ARABIAN PLATE Bitlis-Zagros suture during the Eocene is still

30 converging with Asia at rates of 1.9 to 2.3 Najd Fault System PERSIAN cm per year based on GPS measurements. 0.6 cm/yr (Global measurements of relative plate mo- tions of Arabia with respect to Eurasia show GULF higher velocities of 2.4-3.5 cm per year). This Unstable Shelf continental collision gave rise to the Zagros Orogen and its Cenozoic foreland basin AFRICAN Precambrian OMAN Outcrop which was superimposed on the Paleozoic- PLATE Mesozoic Tethys shelf. The cumulative thickness of sediments in the region thus reaches 2.3 cm/yr

N RED SEA RIFT up to 12 km. The Zagros deformation and salt

° ARABIAN PENINSULA

domes have folded the sedimentary beds into 20 large, gentle anticlines (“whaleback” structural Stable Shelf traps). The western and southern boundaries of the Arabian plate are bounded by the Red Sea and Gulf of Aden rifts. These Neogene RIFT continental rifts have separated Arabia from Africa, and are further pushing Arabia against ADEN OF Asia. The rift-shoulder uplifts have outcropped 1000 km GULF the Precambrian rocks (part of the Nubian- OWEN

N Arabian shield) along the Red Sea and are ° Rasoul Sorkhabi (2009) capped at places by rift volcanic. 10 FRACTURE Illustration: Rasoul Sorkhabi

22 geo expro february 2010 C I P O T

D E N I A L P X E E C N E I C S O E G

Illustration: Rasoul Sorkhabi pnig aezi ad eooc ie in times Mesozoic and Paleozoic margin spanning continental-shelf passive a on ited source rocks, though, is that they were depos East. Middle What is remarkable the about Middle East’s to unique not are >5%) carbon organic total source(with rocks Organic-rich back source to the to thisregion. unique ways in East Middle the in mulation accu and generation petroleum on impacted in some areas. hiatuses Oligocene and Paleocene early with and top) the (toward siliciclastics and carbonates both including sequence foreland with only brief hiatuses; and (3) the Cenozoic rocks sequence,carbonate mainly of up made Permian-Cretaceousthe levels);(2) sea lower middle-Paleozoic the (during sedimentation in gaps long showing and rocks siliciclastic Infracambrian- of sequence, largely Carboniferous consisting The (1) mega-sequences: of to up three into divided be may and meters 12,000 reaches East Middle the in sion including Beydoun( sources various from Compiled region. the of history sedimentation for relevant events geologic major are shown Also times. Phanerozoic throughout area Gulf Kuwait-Persian the of Movement

hs etncsdmnain framework tectonic-sedimentation This succes sedimentary Phanerozoic The Devo- Ediacaran Cambrian Ordovician Silu- Carboni- Permian Jurassic Cretaceous rian nian ferous Triassic Cenozoic M 542 200 146 359 299 444 488 416 0 66 251 a

30° N

C 20° N arb ona Episodes

la 10° N t e sedimen Kuwait ttitudes

EQUATOR sit e , June1998). ta

tion 10° S

20° S G G lacia lacia 30° S tion tion G - - - assembly ondw

NeoTethys Ocean A r

abia-A 40° S ratios). carbon hydrogen-to- lower with but (lipid-rich II I (protein/lipid-rich algal organic matter) and types kerogen oil-prone contained marls and shales marine these Moreover, cost. the off sites upwelling nutrient-rich and ronments, rises, sea-level tageof anoxic (reducing) envi relatively stable conditions, which took advan uasc 1020 tik n ye locality), type in thick m 150-200 Jurassic, rocks the include Sargelu Formation (Middle source classic these of Some eon). Pha nerozoic the of 30% than less for (accounting sediments Jurassic-Cretaceous from erated organic matter. of amounts exceptional with sediments the enriched that current upwelling major a to during the Silurian the Middle East was close Parrish, Judith ( circulations atmospheric and tinents con Paleozoic of modeling Paleogeographic Africa. North and East Middle the of parts other some in in found also Shale but Arabia Qusaibah Saudi the called shale “hot” Silurian the is East Middle the in generation A A Zagr R ana no no ed S G n o te uk hrzn fr petroleum for horizons lucky the of One Over 70% of the Middle East oil was gen was oil East Middle the of 70% Over ondw breakup xic e xic e os or

PaleoTethys Ocean sia c ea r 50° S P v v angea ana en en if o ollision AAPG Bulletin ting gen t ProtoTethys Ocean t 60° S M y

600 500 400 300 200 100 0 a 1.0 R W Global Relative change ising Global sea level change ar ming G W (first order) lobal ar , June 1982) shows that ming 0.5

Rasoul S Present sea level Falling ork habi (2010) 0 - - - - - Gondwana was split apart, and as rift volca rift as and apart, split was Gondwana processes andhigh standsea-levels. sedimentation organic-rich from benefit to position favorable a in west-east,and almost oriented shelf wide its with basin pointed enclosed partly shape a thus was it west; in toward (thinning) triangular was Tethys Bulletin AAPG Murris,J. (R. that twice least at of length a enjoyed a 2000-3000 km-wide wide shelf and it Equator; organic-rich warm, the to close located then Neo-Tethys was times. taceous Cre and Jurassic the during of shelf Neo-Tethys extent and position the consider to the Persian areas. Gulf age- and and Iraq in formations Iran limy-shale equivalent SW of basin Zagros the in Kazhdomi Formation Cretaceous, (Middle and 200 m thick) thick), m 100 (Lower Cretaceous, Formation Gadvan thick), m 800 over Cretaceous, (Lower Formation Garau category. second the in included are rocks source Rich high-energy by platforms. carbonate-evaporite from margins separated basins euxinic (sediment-deficient) starved with marked is under differentiation and deposited conditions, transgressive were which or platform carbonates, shelf carbonate differentiated (2) and basin, the into brought were clastics when regressions marine during deposited and m 100 to 30 from thickness in ranging cakes”) (“layer with cycles with beds) clayey clastic (mixed ramps Carbonate (1) egories: cat two into East Middle the of carbonates Mesozoic the divided has J. Murris tions,R. time. position ataright East wasinaright Middle the and events these from benefited most Neo-Tethys period. laid that during sediments down marine of richness organic the in factor key a - populations plankton of radiation profuse a to led turn, in oceans, of contents nitrogen-phosphorus-carbon the in increases Warmseas,and climate,high-stand times. Cretaceous mid-late in maxima level sea- for evidence stratigraphic sequence with increased volcanic activities). This is consistent ic carbon dioxide concentrations (mainly from warming due to a rapid increaseglobal in atmosphersevere of time a was shown Ma 125-85 that have sediments marine Cretaceous analyses of planktonic foraminifera from mid- and Oxygen- arcs). island or margins ridges continental mid-ocean (along outpourings enriched with nutrient elements from volcanic became waters ocean and rose temperatures nism and sea-floor spreading developed, ocean n ae uascEry rtcos times, Cretaceous Jurassic-Early Late In Toneed we rocks source rich these explain Based on their sedimentary Based facieson distribu their sedimentary , May 1980). Moreover,Neo- 1980). May , geo expro februarygeo 2010 23 - - - - - TOPIC GEOSCIENCE EXPLAINED

continental land North West Shelf ~200 Ma (Early Jurassic) shelf/shallow marine World paleogeogra- into the storage and trap deep ocean phy in the Early Jurassic The Middle East is renowned for its rich car- New Non-Exclusive 3D Seismic Surveys N (~200 Ma) when the bonate oil reservoirs. Such reservoir rocks are 60°N Middle East was part of

P Gondwana passive mar- also found in North America and Western gin submerged under the Siberia (mainly Paleozoic), Central-South

30°N A warm equatorial waters of America (mainly Mesozoic), and Southeast LAURASIA Neo-Tethys. The triangular P ys Asia (mainly Miocene). In the Middle East, N eth PaleoT Neo-Tethys Ocean had a lock Cimmerian B wide N andEO-T E longTHYS shelf, re- however, carbonates were deposited on a long A T T stricted on the western end E and wide shelf from the Permian to the Paleo- but open to the east. The N cene with insignificant hiatus. Even after the EQUATOR idea of trade winds and H T Neo-Tethys ocean currents Arabia-Asia collision, carbonate sedimenta- G A H (concentrating nutrients for tion continued in a very shallow marine en- GONDWANA E Y planktons) comes from

L vironment (an ongoing process in the Persian S Irving et al. (Canadian Gulf ). Indeed, large oil fields in the Middle Cartier A A Journal of Earth Science, S Jan. 1974). These con- East have thick stacks of multiple carbonate S ditions, which favored payzones. Cartier West 30°S A deposition of organic-rich Limestone and dolomite reservoirs of the source rocks and thick car- 60°S bonates, prevailed in the Middle East have fairly good porosity and S Middle East until the latest permeability. Primary porosity has been well Cretaceous. Tethys ocean current preserved in packstones and grainstones such Trade winds as those of the Upper Jurassic Arab Formation

Illustration: Rasoul Sorkhabi Rasoul Sorkhabi (2009) widely spread in the Middle East. In Saudi Zeemeermin Arabia’s Ghawar field (the world’s largest oil Central Southern Period Syria SW Iran UAE Oman Ma Saudi Arabia Iraq field), two producing members (C and D) of Quaternary 1.8 the Arab Formation, respectively, have thick- Pliocene 5.3 nesses of 30 m and 80 m, and a porosity of Miocene 20%. The same formation in the UAE ranges 23 from 130-240 m in thickness and 10-30% in Oligocene 34 porosity. Moreover, the Zagros deformation Eocene has created fracture networks enhancing per- Phoenix 56 meability, especially in cemented limestones Paleocene 66 such as the Oligocene-Miocene limestones Upper of southwest Iran (Asmari Formation) and 89 Barrow Ultracube

e o u s eastern Iraq ( Jerribe Formation), where its Middle

e t a c thickness ranges from 120-480 m, and has a 112 r C Lower porosity of 8-24%. Eendracht 146 Apart from marine shale and marl cap Upper 3D Acquisition Outlines* 159 rocks, a vast part of the Middle East basins Middle 3D Reprocessing Outline*

a s i c also contains evaporite beds, which are ef-

169 J u r ficient seals because of their ductility. The *Surveys are subject to change Lower main evaporite horizons include (1) the In- 199 Triassic fracambrian Hormuz salt; (2) Triassic inter- 251 bedded evaporites; (3) Late Jurassic Gotnia- Fugro Multi Client Services have many new and exciting 3D projects Permian Hith Formation; and (4) and the Miocene 299 Carboni- Gachsaran Formation. In this manner, the on the North West Shelf of Western Australia. ferous 359 entire Phanerozoic succession is bounded by Devonian evaporite seals both at the bottom and on 2 416 Cartier and Cartier West - acquiring ~3,500 km in the Timor Sea ?? the top. Silurian 2 444 These ductile evaporite and shale beds Zeemeermin 3D - recent acquisition of ~ 1,160 km Ordovician have also acted as detachment horizons for 2 488 the Zagros thrust structures, thus producing Phoenix - planning to acquire ~1,100 km in the Canning Basin Cambrian ?? 2 542 vertical compartments of petroleum systems Eendracht 3D - currently acquiring ~8,000 km in the Carnarvon Basin Infra- ?? ?? ?? cambrian within the sedimentary succession. ~570 Barrow Ultracube - together with Searcher Seismic are reprocessing ~8740 km2 LEGEND Hiatus Major source Major reservoir zagros deformation and Shale/ Conglomerate Mudstone Limestone Evaporite salt domes Basin modeling from various parts of the Sandstone Marl Dolomite Volcanics Fugro Multi Client Services Rasoul Sorkhabi (2009) Middle East has shown that the Jurassic- Owen Dyer Stratigraphy and petroleum source-reservoir rocks of selected areas in the Middle East. Data Cretaceous source rocks were buried to oil- ...see us first P: +61 8 9420 6085 compiled mainly from Beydoun (1999) and Alsharhan & Nairn (2003). generation-window temperatures during the M: +61 413 607 363 Illustration: Rasoul Sorkhabi Neogene, and this partly overlapped in time www.fugromcs.com.au E: [email protected] 24 geo expro february 2010 TOPIC GEOSCIENCE EXPLAINED

with Zagros deformation and development of summing-up large anticlines as structural traps. For petroleum to be successfully gener- Three important features of Zagros defor- ated, migrated, accumulated, and preserved, mation helped to preserve oil accumulations all elements and processes of the petroleum in the Middle East: system, including organically rich and ther- Firstly, the Cenozoic Zagros foreland basin mally matured source rocks, porous-permeable was superimposed on the Paleozoic-Meso- reservoir rocks, effective extensive cap rocks, zoic Tethyan sediments, providing an over- and appropriate time relations between oil mi- burden necessary for preservation as well as gration and trap formation should be present. burial heating of the underlying source rocks. Obviously, the Middle East qualifies all these Secondly, the relatively slow motion of the conditions to a high degree and quality. African-Arabian plate during the Cenozoic Since our discussion is at the regional scale of prevented a wide-spread, severe tectonic de- the Middle East, we have to simplify and gen- formation unlike what occurred in other parts eralize the issue and thus ignore variations in Photo courtesy of Saudi Aramco of the Tethyan belt, most notably in the Hi- structural and sedimentation histories within View of the Qatif Central Producing Plants during malayas. (The Indian plate has moved at a rate the region. One such variation, for example, is its construction in the early 2000s. Completed in of 5-6 cm per year after the India-Asia col- that as we move away from the Precambrian 2004, these facilities, according to Saudi Aram- lision at 50 Ma, which is about three times outcrops in western Saudi Arabia toward the co, produce 800,000 barrels per day from reju- faster than that of the African-Arabian plate High Zagros in southwest Iran, the basin(s) venation of the onshore Qatif field (first produced in 1951) and the offshore Ab Safah field (first over the same period.) become deeper and Mesozoic-Cenozoic sedi- produced in 1966). Thirdly, the presence of ductile Hormuz ments attain enormous thicknesses. Few wells salt at the base of the Phanerozoic sediments have, indeed, penetrated the Paleozoic sections helped to detach the sedimentary cover in these deeper parts of the basin. Moreover, exhume the entire Tethyan shelf sediments; from the underlying igneous-metamorphic some parts of the Middle East, notably the (11) Large “whaleback” anticlines generated by basement rock. Therefore, Zagros deforma- central and northern Iran, virtually remain un- the “gentle” Zagros compression (folding and tion evolved as a thin-skinned tectonic de- explored. While keeping these shortcomings thrusting) or salt diapirs provided abundant formation in which the basement rock did in mind, several key points may be highlighted structural traps for oil accumulations. not override the sedimentary cover nor did it to explain the abundance of oil in the Middle exhume the entire Tethyan shelf sediments. East: Bibliographic Notes (This scenario has happened in the thick- (1) A 500-million history of sedimentation on Since the 1950s, a number of petroleum geolo- skinned tectonic deformation and uplift of the passive continental margin of Gondwana; gists working in the Middle East have opined on the Himalayas.) (2) Sedimentation largely within latitudes 30° the richness of oil in that region; classic papers Indeed, in the Zagros Mountains, Precam- North-30° South where climate is warm and published in the AAPG Bulletin include Baker brian metamorphic rocks are not outcropped, organic activity is at high levels; and Henson (October 1952); Law (January and those metamorphic schists and granites (3) Wide, long (east-west oriented) shelf of 1957); Kamen-Kaye (December 1970); Murris in Zagros, which were once thought to be of Neo-Tethys during the Jurassic-Cretaceous; (May 1980); Bois et al. (September 1982); Precambrian age, have been dated as Paleo- (4) Favorable position of the Middle East and Klemme & Ulmishek (December 1991). zoic by high-resolution radiometric methods. during the mid-Cretaceous global warming, The Late Z. R. Beydoun also discussed this issue Note that a thin-skinned deformation in the sea level rise, and plankton abundance; in Episodes, June 1998. Zagros fold-and-thrust does not overrule the (5) Marine source rocks containing oil-prone Habitat of Oil, edited by Lewis Weeks possibility of basement deformation at deeper kerogen types; (1958) is the proceedings volume of an AAPG levels; it simply means that deformation of (6) Proximity of interbedded source rocks to symposium on this topic, which also includes the sedimentary cover has been decoupled reservoirs minimized oil migration pathways; several classic papers relevant to the Middle from that of the basement (of which we have (7) An enormous thickness of sediments (pre- East. I have benefited from all these sources. little knowledge). Perhaps, millions of years dominantly carbonates but some clastics as For information on the geology of specific in the future, Zagros will also look much like well) provided the necessary storage for the basins and chronostratigraphic events in the today’s Himalayas, especially if the motion of huge amounts of generated oil; Middle East, I have found review papers in the Arabian Plate, currently being pushed by (8) Presence of effective regional seals, both GeoArabia as well as the following volumes the Red Sea rifting, becomes faster as the Red marine shale and evaporites, at the bottom, on particularly helpful and handy: Sea develops into a wide ocean. the top, and within the sedimentary package; Alsharhan, A.S., and Nairn, A.E.M. (2003) The Infracambrian Hormuz salt has also (9) Superimposition of the Cenozoic Zagros Sedimentary Basins and Petroleum Geology of created salt diapris and folds, which provide foreland basin atop the Tethyan shelf sedi- the Middle East (Amsterdam: Elsevier) favorable structural traps for oil; these salt ments; Beydoun, Z.R. (1991) Arabian Plate Hydro- movements date back to the Late Cretaceous. (10) Relatively slow motion of the Arabian carbon Geology and Potential: A Plate Tectonic Although the Hormuz salt has been mapped plate and the presence of ductile evaporite- Approach (AAPG Studies in Geology #33, only in some areas of the Middle East, its shale layers at the base of the Phanerozoic Tulsa) true extent is not precisely known as it has sediments resulted in a thin-skinned tectonic Sharland, P.R. et al. (2001) Arabian Plate not been drilled in areas such as southern Iraq regime in which the Precambrian igneous- Sequence Stratigraphy (GeoArabia Special or the UAE. metamorphic basement did not override or Publication 2, Bahrain)

26 geo expro february 2010 TOPIC GEOSCIENCE E X P L A I N E D

The First Oil Discoveries in the Middle East Flashbacks on the first discoveries of oil fields in the Middle East.

rasoul sorkhabi

1908 (May 26): 1956: 1956 (October): Masjid Sulaiman field (Masjid Sulaiman-1 well), Marmul field (Marmul-1 well), Oman, by Petro- Karatchok field (Karatchok-1 well), northeastern southwest Zagros basin, Iran (Persia) by the Con- leum Department of Oman (subsidiary of IPC). Syria, by the American independent James W. cessions Syndicate Ltd. (owned by Englishmen Reservoirs: Umm Er Radhuma (Paleocene) 576 Menhall Drilling Company. Reservoir: Massive William Knox D’Arcy and Lord Stathcona, and m deep (18° API) and Biyadh sandstone (Lower Limestone Formation (Cretaceous), 3155 m deep; the Scottish Burma Oil), forerunner of the Anglo- Cretaceous) 854-976 m deep (20.8° API). The oil 19-21° API. Production began in 1969. Persian Oil Company (later British Petroleum). field was non-commercial. 1963-67: The first Reservoir: Asmari limestone (Oligocene-Early Mio- producing fields, Yibal (1963, depth 2275 m, 1984 (March 4): cene), 354 m deep; oil 39.4° API gravity. 38° API), Natih (1963, depth 2202 m, 31° API) Alif field (Alif-1 well), Ma’rib Jawf graben of and Fahud (1964, depth 590 m, 33.6° API) (all the Sab’atayn basin, Yemen, by the American 1927 (October 14): Cretaceous limestone), in Oman were discovered Yemen-Hunt Oil Company. Reservoir: Sab’atayn Kirkuk field (Baba Gurgur No. 1 well), Kurdis- by Shell and Partex (Gulbenkian Foundation). Pro- Formation (Upper Jurassic), 2400 deep; oil 43 tan region, Iraq, by the Turkish (Iraqi) Petroleum duction began in 1967. API. Production began in 1987. Company (IPC, a consortium of the Anglo-Persian, Shell, Francaise des Petroles, American Near East Development Corporation, and Gulbenkian Foun- dation). Reservoir: “Main Limestone” or Kirkuk for- FIRST OIL DISCOVERIES IN THE MIDDLE EAST mation (Asmari equivalent) limestone (Oligocene), depth unknown; oil 36° API. Production began 40E 50E 60E in 1934. 40N

1932 (June 1): Jabal Dukhan field (Jabal Dukhan-1 well), Bahrain, Caspian by the Bahrain Petroleum Company (a subsidiary Sea of the Standard Oil of California); Reservoir: Waisa limestone (Cretaceous) at depths of 600- 750 m; oil 38° API. Production began in 1934. S Y R I A (1956) 1938 (February 23): I R A N Burgan field (Burgan-1 well), Kuwait, by the Ku- [PERSIA] wait Oil Company (owned by the Gulf Oil and (1908) the Anglo-Persian). Reservoir: Burgan sandstone I R A Q 30N (Middle Cretaceous), 1120 m deep; oil 32.5° (1927) API. Production began in 1946. P e r si a n 1938 (March 4): KUWAIT Dammam field (Dammam-7 well), eastern Saudi (1938) Arabia, by the California Arabian Standard Oil G u l f Company (a subsidiary of Standard Oil of Cali- BAHRAIN G u l f of fornia). Reservoir: Arab limestone (Upper Jurassic), (1932) O m a n 1441 m deep; oil 34-35° API. Production began R e d S e a S A U D I QATAR A R A B I A in the same year. (1940) O M A N (1938) U A E (1956, (1953) 1940 (January): 1963) Dukhan field (Dukhan-1 well), Qatar, by the Pe- 20N troleum Development of Qatar (a subsidiary of the Anglo-Persian/IPC). Reservoir: Zekrit (Arab) limestone (Upper Jurassic), 1733 m deep; oil 37° API (Limestone 3) and 42° API (Limestone 4). Produc- tion began in 1940 and export began in 1949. Y E M E N A r a b i a n 1953: (1984) S e a Bab (or Murban) field (Murban-1 well), Abu A d e n Dhabi (later part of the United Arab Emirates), by 0 300 km Abu Dhabi Petroleum Company (formerly Oil De- G u l f of velopment of Trucial Coast, a subsidiary of IPC); 0 300 miles Reservoir: Kharaib Formation (Lower Cretaceous 10N limestone), 3,776 m deep; oil 40° API. Produc- tion began in 1963. Rasoul Sorkhabi (2010)

28 geo expro february 2010 recent advances in technology Marine Seismic Sources part i: air-guns for non experts

This series on marine seismic sources will summarize salient points for geoscientists who need to sharpen their rusty skills in seismic source technology. It will also discuss the effect seismic sources have on marine life.

A seismic source is defined as any device which releases 6m, except for refraction studies when a deeper deploy- “Double, energy into the earth in the form of seismic waves. The ment is needed. The gun pressure mostly used by the double, toil and major source type in marine exploration is the air-gun seismic industry is 2,000 psi (138 bar) and during a array, which since the 1970’s has been by far the most survey, the guns fire every 10-15 seconds. trouble; Air popular. The air-gun can be described as a chamber of It is common to arrange several (2-4) air-guns in a guns fire and compressed air that is released rapidly into the sur- cluster, with the guns so close together that they behave ocean bubble. rounding water to create an acoustic pulse. The air gun as a larger single gun. The main purpose of clustering is the most commonly used source because the pulses is to improve signal characteristics, since the bubble With apologies to are predictable, repeatable and controllable, it uses com- motion (see below) is reduced by this configuration. Shakespeare’s three pressed air which is cheap and readily available, and it The energy sent out by air-gun arrays - isdomi witches in Macbeth, has only a minor impact on marine life. nantly directed vertically downwards. The broad and thanks to our col- band of frequencies from the array form a pulse with leagues Bill Dragoset peak-to-peak amplitude in the range 14-28 bar-m, and Jan Langhammer. size and geometry An air-gun volume is measured in litres (l) or more corresponding to 243-249 dB re 1 μPa-m vertically commonly, by the conservative petroleum geophysi- downward. The amplitude levels emitted horizontally cist, in cubic inches (in3). Typical volumes of individual tend to be 15-24 dB lower. These numbers are fre- air-guns used by the exploration industry vary from 20 quency dependent. By filtering out high frequencies in3 (0.3 l) to 800 in3 (13.1 l), while academic seismic there is less deviation between amplitude levels verti- refraction studies can use volumes up to 1600 in3 (26.2 cally and horizontally. l). An air-gun array consists of 3 - 6 sub-arrays called Here, ‘dB re 1 μPa-m’ means decibel value peak-to- strings, each string containing 6 - 8 individual guns, so peak relative to the reference pressure one micropascal that the array usually involves between 18 and 48 guns, at a reference distance of one metre. Confusing units? although in special cases as many as 100 guns an array Read Box 1 and we will guide you through the physical can be used. The air-gun array volume is the sum of the principles of air-guns and the basic sound measurement volumes of each gun, and is typically in the range 3,000- units. Our focus in the present article is on the vertically 8,000 in3 (49.2-131.6 l). downward travelling ‘far-field’ signature of an air-gun The air-guns hang in the sea beneath floats between array as this signature provides a quantitative measure 3m and 10m below the sea surface, generally at about of the array’s performance.

Lasse Amundsen is Chief Scientist, Geophysics, at Statoil.

Top: Single air-gun and three-gun cluster (www. bolt-technology.com). Bottom: Pictures of air Martin Landrø is profes- bubbles 1 ms, 1.5 ms, sor in Applied Geophys- and 7 ms after firing a ics at NTNU, Trondheim, small air-gun in a tank Norway. (Langhammer 1994).

32 geo expro february 2010 Martin Landrø and Lasse Amundsen © Schlumberger © WesternGeco

Note Man Kneeling Seismic vessel towing two air-gun arrays at 6 m depth. One array, consisting of three strings with in total 24 guns, is sketched in plan view. It measures 15 m x 16 m (inline x cross-line). The numbers are Part of an air-gun array onboard a vessel. gun volumes in in3. The total volume is 3,397 in3.

bubble oscillations pressure signature. However, another pulse simultane- When compressed air is suddenly released into the water ously travels upward from the source, is reflected down an oscillating bubble forms. This process is described in at the sea surface and joins the original downward- Parkes and Hatton (1986): travelling pressure pulse. This delayed pulse, reflected at Fig 2 Initially, the pressure inside the bubble greatly exceeds the the sea surface, is called the source ghost. From a data hydrostatic (external) pressure. The air bubble then expands processing point of view, the source ghost is considered well beyond the point at which the internal and hydrostatic to be an intrinsic feature of the source wavefield, and pressures are equal. When the expansion ceases, the internal therefore often included in the definition of the source Classification: Internal Status: Draft bubble pressure is below the hydrostatic pressure, so that the pressure signature. bubble starts to collapse. The collapse overshoots the -equi As illustrated in Box 3, the effect of the source ghost librium position and the cycle starts once again. The bubble on the frequency content of the source signature is sub- continues to oscillate, with a period typically in the range of stantial. Therefore, like gun size, the gun depth is an im- tens to hundreds of milliseconds. portant parameter in source and survey design. The oscillation is stopped due to frictional forces, and The useful frequency band of seismic data is between the buoyancy of the bubble causes it to break the sea the first (always at 0 Hz) and the second zeroes in the surface. If we could stop this cyclic motion immediately amplitude spectrum of the source signature. The zeroes after the first expansion of the bubble, the air gun would in the spectrum, caused by the source ghost and there- create an ideal signal close to a single spike and similar to fore called ghost notches, implies that there is no signal a dynamite explosion. However, due to the cyclic bubble at these particular frequencies. motion, the signal from a single air gun is far from ideal. If high-resolution seismic of the shallow subsurface is As explained in Box 2 on bubble motion, the dominant the objective, it is important to extend the high-frequen- frequency of the bubble oscillations decreases with in- cies as much as possible. For a source at a depth of 3.75

creasing gun volume, or with increasing gun pressure, or m, the second ghost notch is at frequency f1=200 Hz. with decreasing source depth. Therefore, small guns emit But the low-frequency amplitudes are much lower than higher frequencies and big guns emit lower frequencies for a source depth of, for example, 15 m. As low frequen- – like a bell choir. The geophysicist wants a broad band cies improve penetration into the subsurface, a shallow The air bubble from a of frequencies. source is not recommended for a dee-looking survey. By 600 in3 gun at 3 m However, as we will explain, the source ghost (see Box comparison, a 15 m source depth has nice low-frequency depth. The released air 3) has a detrimental effect on broad-band spectrum. characteristics for good penetration, but the ghost notch produces a steep-fronted

at f1=50 Hz has a detrimental effect on resolution. A shock wave that is ob- survey with both low-frequency and high-frequency observed as ripples on the the source ghost sea surface (pictures 1 The time domain pressure pulse that is emitted by the jectives is difficult to realize. It can be seen from this that and 2) before the bubble single air-gun in the vertical direction is called the the survey objective dictates the source depth. breaks the surface. © Statoil

geo expro february 2010 33 recent advances in technology

Pressure signature of the sound pulse of a single BOX 1 40-in3 air-gun. The near- Definitions field signature (upper trace) shows the measurement Hydrophones are sensitive to sound pressure, which of the released air produc- is measured in micropascals (μPa). By tradition, the ing a steep-fronted shock geophysicist uses a different pressure unit, microbar wave followed by several (μbar). One bar is equivalent to 1011 μPa. oscillations resulting from the repeated collapse and The far-field signature of an air-gun array, expansion of the air bubble. measured vertically beneath, is used to define the The signal strengths of the nominal source level. This is the acoustic pressure 1 direct wave and the first m away from its hypothetical point source equivalent bubble are P and B, respec- that would radiate the same amount of sound in the tively. The near-field peak- far-field as the actual source. Units are in bars at 1 to-bubble ratio is PBR=P/B. m, abbreviated as bar-m. For example, 100 bar-m The far-field signature (lower trace) shows the effect that means that if the array were a point source and a the source ghost has on the hydrophone were 50 m away, then the hydrophone near-field signature. The would detect a pressure of 2 bar. peak-to-peak amplitude P-P In presenting sound measurements, acousticians (the distance between the use ratios of pressures; in underwater sound the positive peak of the primary adopted reference pressure is one μPa. Further, ac- and negative peak of the ousticians adopt the decibel (dB) scale so that sound ghost) is 2.3 bar-m. The far-field peak-to-bubble ratio pressure level (SPL) of a sound of pressure S is SPL (dB) is PBR=P-P/B-B=1.9. The = 20 log10(S/S0) where S0 is the reference pressure. bubble period is tau=60 ms The standard for specifying air-gun signal levels is the (Langhammer 1994). peak-to-peak (P-P) level, which is the maximum negative-to-positive measurement of the air-gun signature. the air-gun signature The seismic survey literature refers to P-P pressure am- Acknowledgment The air-gun ‘signature’, recorded by a hydrophone below plitudes in bar-m. P-P can be converted to source level We thank WesternGeco the gun, has three characteristic features: the direct L in dB re 1 μPa-m as follows: L (dB re 1 μPa-m) = for providing useful illustra- arrival produced when the gun fires; the source ghost; s s tions to this article. 20 log(P-P)+220. Acoustic pressures of 10-20 bar-m and the bubble pulse caused by the expansion-collapse correspond to 240-246 dB re 1 μPa-mP-P. References cycle of the air bubble. The signature is characterized by The source amplitude spectrum level gives source A Ziolkowski 1970; A meth- two parameters: the primary pulse peak-to-peak (P-P) amplitude strength versus frequency. It is common to od for calculating the output amplitude, or “strength”, the useful part of the signal, normalize the amplitude spectrum in dB relative to pressure waveform from an and its bubble period. These two characteristic param- air gun: Geophys. J. R. astr. 1 μPa/Hz at 1 m, abbreviated as dB re 1 μPa/ Soc. 21, 137-161. eters depend on the air-gun’s size, initial firing pressure, Hz-m. Because the reference pressure 1 μPa is a G Parkes and L Hatton and depth. small pressure, a moderately sized air-gun array will 1986; The marine seismic have a spectrum that peaks above 200 dB above source: Kluwer. source arrays this reference level. J Langhammer 1994; Ex- Two important parameters of an air-gun array signa- perimental studies of energy loss mechanisms in air-gun ture are its peak-to-peak (P-P) strength and primary- bubble dynamics: PhD the- to-bubble ratio (PBR). The PBR should be as high as sis, NTNU. possible so that the air-gun array signature is close to an used to define a nominal point-source level, at 1 m from B Dragoset 2000; Intro- ideal pulse. To find the P-P strength of an array, its sig- the centre of the array, by multiplying the signature by duction to air guns and air- nature is measured at a distance from the source known the radial distance from this point to the hydrophone. gun arrays: Leading Edge, 8, 892-897. as the far-field point, a point where the output signals This nominal point-source level is a theoretical sound J Caldwell and B Drago- of the individual guns interfere constructively, typically pressure level. Because of partial destructive interference set 2000; A brief overview 250-300m beneath them. This far-field signature is then between the signals of the individual guns, the actual of seismic air-gun arrays: level at this point in reality tends to be 10 times (20 dB) Leading Edge, 8, 898-902. lower than the nominal level. The P-P strength (related to this nominal source level) is defined as the difference in absolute amplitude between the peaks of the primary and ghost arrivals. The P-P amplitude of, for example, the 3,397-in3 array is 102 bar-m, corresponding to 260 dB re 1 μPa-m. © WesternGeco © Typical arrays tend to produce levels of 243-249 dB re Far-field pressure signa- 1 μPa-m, corresponding to 14-28 bar-m. The seismic tures of individual air-guns vary with gun volume. The industry sometimes gives output levels in root-mean- tuned pressure signature is square (rms) peak-to-peak amplitudes (rms P-P). The obtained when the six guns dB reduction of rms P-P compared to P-P is around 3 are fired simultaneously; dB since the maximum peak and trough amplitudes are PBR=8.6. approximately equal.

34 geo expro february 2010 Location of the Faroe FSB dataset SHETLAND ROCKS! Shetland Basin (FSB) dataset line location map Improved Sub-Basalt Structural Imaging Extensive thick sequences of basalt dominate the northwest flank of the Faroe Shetland Basin. Recent reprocessing of this long offset data dramatically improves the interpret- ability of the sub-basalt structures. See full story starting on page 39.

FUGLEEOYE RIDGE SYSTEM ? FAROE SUB - BASIN ? FUGLEEOYE RIDGE SYSTEM ? FAROE BASIN ? EAST FAROE HIGH ? NORTH CORONA SUB - BASIN CORONA RIDGE FLETT SUB - BASIN FLETT RIDGE COMPLEX FOULA SUB - BASIN NORTH WEST SHETLAND BASIN Glenlivet RONA-RIDGE look-alike FAROES CS UKCS

36 geo expro february 2010 geo expro february 2010 38 topic frontier exploration

Source signature and am- where compressional features within the Early Palaeocene reprocessing discussion BOX 2 plitude spectrum for the 3,397-in3 air-gun array. section are evident. Within this area it seems possible to cor- What were the main processing elements which led to this im- Bubble motion relate a deep reflection sequence representing a Devonian/ provement? The peak-to-peak ampli- The physics of air bubbles from marine air-guns tude is 102 bar-m. WeSt of Shetland: Lewisian basement horizon across to the Rona Ridge area. Three key approaches were used: is complex. The temperature inside the bubble To the northwest the profile traverses the very interesting • Preservation and enhancement of low frequency signal can drop to around minus one hundred degrees • Noise Attenuation in multiple domains Improved Sub–Basalt Imaging Corona Ridge feature containing a section imaged down to Celsius, causing ice crystals to form. There great depth. Could the Corona Ridge be formed of a set of • Full Sequence Migration Velocity Analysis is also evidence that the bubble comprises a fault block elements which as a whole constitute an inverted number of small bubbles rather than one large Newly reprocessed long offset seismic data from the Faroe Shetland Basin now basin? Careful attention to the preservation and enhancement of low one. provides a tool to enable interpreters to produce meaningful correlation in the The Rona, Flett and Corona Ridge features all trend in frequency signal, multiple and noise removal are seen to be Nevertheless, to a first approximation, the the mainly NE/SW direction through this area each of them crucial to improving signal-to-noise beneath the basalt. There is parameters that govern the time behavior of sub-basalt section and raises some exciting geological questions for the West of showing offsets caused by movements along the NW/SE no need to compromise the frequency content of the overlying the bubble oscillation are surprisingly “simple”: 1/3 1/3 5/6 transfer fault system active along the whole of the Atlantic Tertiary section when reprocessing shallow towed datasets for T = C1 P V / P0 . Here, P and V are Shetlands. Margin. sub-basalt targets. the initial internal pressure (firing pressure) and

Northwest of the Corona Ridge the profile traverses a The third approach, Full Sequence Migration Velocity volume of the air before it is released and P0 is feature named the North Corona Sub–basin. It is founded on Analysis, is seen to be the key to improving the structural in- the hydrostatic pressure. C1 is a constant that bent baumbach, project development, tgs - bedford, uk a set of fault block elements. It is possible to correlate reflec- terpretability of concealed Mesozoic and Palaeozoic structures. depends upon the air gun details. tor horizons across the basin even at depth. The Eriboll well Recent advances in compute power mean that this procedure The dominant frequency of the bubble motion, f=1/T, then decreases with increasing 213/23–1 drilled to the southwest of the profile encountered a can now be run within the time frame of a quick turnaround gun volume, or with increasing gun pressure, or BOX 3 TGS has successfully completed the reprocessing of the first carboniferous section underlying a Tertiary–Mesozoic section large scale production project. It permits the early involvement geological discussion with decreasing hydrostatic pressure (and thus, Source ghost 6,500 km of a large 10,000 km long offset regional dataset in the This summary, built on past and current exploration ideas high- however the knowledge of the stratigraphic section within of interpreters, to whom the choice of a range of alternative source depth). Faroe Shetland Basin (FSB). The remaining 3,500 km is due to lights some new geological questions for the West of Shet- this sub-basin is still incomplete. structural images may be presented. Each alternative has the The physics of the source ghost related to marine sources is simple. The By tradition, the seismic industry quotes firing upward travelling part of the source signal cannot escape into the air, as the be finalised by February 2010. The objective of the reprocessing lands. Note the anticline feature at depth located within the area processing and signal-to-noise characteristics of a final section pressure in pound force per square inch, psi was to improve overall imaging with particular emphasis on the Looking at the West Shetland Basin area, the stratigraphic named the Faroe High. and allows a ‘composite’ image to be built. The final time domain sea surface acts as a mirror, and reflects the signal downwards with opposite (psi=6894.76 Pascals; a Pascal is a Newton polarity. This source ghost pulse is delayed in time with respect to the initial sub–basalt section. section known to be present in this basin consists of a full The profile traverses further into the Faroese Continental migration velocity field should provide an excellent reference per square meter). downwards primary pulse from the source. Geometrically, the source ghost The fold out profile heading this article shows an example of column of Tertiary section overlaying an Upper Cretaceous Shelf (CS) across the Faroe–Shetland Escarpment and on to model for initial passes of pre-stack depth migration and to- appears to originate from the mirror image of the seismic source. The time the sub–basalt imaging achieved by methodical analytical pro- section resting unconformably on the Lewisian basement. an area where the sub-basalt section rises dramatically to a mography-based velocity updates. Air-gun strength delay therefore is given by τ =2d cosθ/c, where d is the source depth, c is cessing using TGS’ latest processing software. Moving northwest the profile traverses the Rona Ridge. position with the top volcanic horizon near the water bottom. The strength of an array is: the sound of speed in water, and θ is the offset angle of the initial downwards To observe the dramatic improvements achieved in the 2010 The Clair oilfield further south is hosted on the Rona Ridge Further observe the dramatic thickening of the individual conclusion (1) Linearly proportional to the number of guns primary pulse measured from the vertical axis. reprocessed data, a comparison between the original processing complex, with oil accumulated in a Devonian Sandstone res- basalt sequences into the Faroese CS and the much improved The West of Shetlands contains three of the largest producing in the array. All else being equal, a 40-gun The frequency spectrum of the composite signal (primary and ghost) is and the newly processed profile is shown. The recent reprocessing ervoir overlain by a Carboniferous formation. This gives an resolution achieved within the basalt sequences particularly fields on the UKCS today yet it still has vast tracts of open array generates twice the amplitude of a |G(f)| = 2 sin(2 π f d cosθ/c). has brought out significant improvements of key importance in indication of what might be present within the Rona Ridge acreage. It is clear that this reprocessed dataset now gives the 20-gun array. in the shallow, where seismic sequence analysis now seems to This spectrum has zeroes called ‘ghost notches’ at frequencies fn = n c/(2 the understanding of the sub–basalt geological setting, allowing in the Victory area. None of the wells drilled in the Clair area be possible. Looking at depth in this section the immediate interpreter the ability to carry out evaluation, correlation and (2) Close to linearly proportional to the firing d cosθ), where n is zero or positive integer. The first notch (n=0) is always at pressure of the array. A 3000-psi array meaningful correlation across the West of Shetlands area. penetrated into basement. The overburden section deposited impression is that one is looking at a major set of fault blocks mapping within the prospective sub–basalt interval. f0=0 Hz. The useful frequency band in seismic is inside the first and second has 1.5 times the amplitude of a 2000-psi on top of the apex of the Rona Ridge consists of a nearly full initially positioned at depth, but then from late Palaeocene/ notch frequencies (inside f0 and f1) of the spectrum of the composite signal. array. Tertiary section with a late Palaeocene formation resting on Early Eocene to present was subjected to severe compression Further Information the ridge apex. mainly in a WNW – ESE direction. TGS have submitted an abstract with further details of the reprocess- (3) Roughly proportional to the cube root of its volume. The source ghost The sediment section thickens dramatically immediately ing to the forthcoming EAGE conference in Barcelona. reflects at the sea

west of the Rona Ridge into the Foula Sub–basin. Deep surface to join the The number of guns provides the greatest seismic imaging is observed in the basin. Note the rollover primary downwards influence on the array strength, not the firing pulse from the feature observed in the Palaeocene section right next to the pressure nor the total volume. source. The ghost ridge – a possibly similar feature to the recent gas discov- appears to originate ery Glenlivet. Good control on the anticipated stratigraphic from a virtual source column within the basin is provided, based on data available at the mirror loca- from wells drilled further south. tion of the physical source. A near full Tertiary section rests unconformably on Late Cretaceous and Late Early Cretaceous. A hiatus unconformi- It is important to remember that the time-domain spec- ty separates the Cretaceous from an underlying Late Jurassic ifications of P-P strength and PBR depend strongly on section which is known to contain the Kimmeridge source the frequency bandwidth of the array’s signature. When rock. Several prospective sandstone reservoirs are present high frequencies are cut the P-P strength and PBR both within the Cretaceous–Jurassic section. The Jurassic rests decrease. unconformably on Permo–Triassic, potential Carbonifereous There are several reasons for deploying air-guns in (another possible source ) and Devonian section. arrays. The first is to increase the power of the source. The Frequency spectra West of the Foula Sub-basin the FSB Profile crosses into basic idea is that a source array of n single sources produces of the composite signal travelling in the Flett Ridge area. The seismic data hints at the Flett Ridge n times the power of the single source. The second is to the vertical direc- being a composition of fault blocks forming the ridge caused minimize the PBR by tuning the array: Guns with differ- tion (θ=0) for source by transpressural/transtensional movements within the fault ent volumes will have different bubble periods, leading to depths at 3.75 m Structural Elements West of Shetland, with main basins, fields and block components. The stratigraphic composition within each a constructive summation of the first (primary) peak and (green), 7.5 m (red) discoveries. The same features are annotated at the top of the FSB of these fault blocks has hitherto been unknown. destructive summation of the bubble amplitudes. and 15 m (black). profile. Further to the west the profile traverses the Flett Sub–basin A comparison between new (2010, below) and original (1999/2000, above) processing illustrating a dramatic increase in quality.

geo expro february 2010 39 40 geo expro february 2010 geo expro february 2010 35 history of oil

The Qatar Oil Discoveries of 1940 and 1960

In January 1940 (now 70 years ago), with the discovery of the onshore Dukhan oil field, Qa- tar joined the Middle East’s oil club. In 1960 (50 years Al-Ruays ago), Qatar’s first offshore BAHRAIN field was discovered. Today, this country, smaller than the Gulf of Bahrain state of Connecticut, pos- sesses the world’s third largest gas reserves, and about 25 billion barrels of oil. QATAR Bir Zekrit Dukhan

Doha Gulf of Salwa Umm Bab Umm Said

SAUDI ARABIA

Image courtesy of NASA A satellite image (taken on 18 February 2003) of the southern Persian Gulf showing the Qatar Peninsula and phytoplankton boom in the nearby waters.

42 geo expro february 2010 U.A.E. 30 km Rasoul Sorkhabi

The Qatar Oil Discoveries of 1940 and 1960

50E Qatar is relatively a small peninsula, 160 km long and 55-90 km 51 E 52 E 53 E

wide, that extends from Saudi Arabia into the Persian Gulf. It is South Pars 27 N 27 an Arab emirate ruled by the Al-Thani family since the 1870s. N 27 From 1872, to the beginning of World War I in 1914, Qatar was Field under the Ottoman Empire. Qatar gained its independence in 1971, after being a British protectorate since 1916. The early Al-Rayyan IRAN twentieth-century history of oil exploration in Qatar is associated Al-Shaheen Illustration by Rasoul Sorkhabi Oil Field with British players in the region. Al-Ruays

1920s … North Gas Field 26 N 26 As early as 1922, Major Frank Holmes (also called “Abu Naft,” N 26 BAHRAIN Al-Khalij or Father of Oil in the Middle East) had his eye on Qatar’s oil BAHRAIN resources. Holmes was a New Zealand-born British miner, army Gulf of officer, and oil businessman who represented the London-based Maydan Eastern and General Syndicate’s ventures in the Middle East, Mahzam Bahrain Bul Hanine and helped obtain oil concessions in Saudi Arabia, Kuwait and N Bahrain in the 1920s (see “The Emergence of the Arabian Oil Idd al-Sharqi S

Dukhan Qatar Arch Industry,” GEO ExPro, 06/2008). However, Holmes, who also Field

Doha 25 N 25 managed to met with Qatar’s ruler Shaikh Abdullah bin Jassim Al-Karkara N 25

al-Thani in Doha in 1923, did not proceed with his ideas because QATAR the British Colonial Office had prohibited oil ventures in Qatar. ABU DHABI

QATAR By 1925, however, such restrictions appear to have eased, for SAUDI ARABIA Arch in early 1926, George Martin Lees, a geologist with the Anglo- 0 km 50

Bir Zekrit Dukhan Persian Oil Company (APOC, later British Petroleum), visited 53 E Dukhan Doha and made a one-day trip to a few outcrops of Qatar, which 50E R. Sorkhabi (2010) 51 E 52 E he rightly identified as Eocene limestone exposed on the crest Onshore geology and the Qatar’s major oil and gas fields. Doha of a gently-dipping anticline. Before leaving, Lees also obtained permission from the Shaikh for exploring the emirate for the fol- Gulf of Salwa lowing two years. Umm Bab 1930s … Umm What renewed the British interest in Qatar’s oil was the 1932 Said discovery of oil in Bahrain by the Standard Oil Company of Cali- fornia. Alarmed by the American company’s success in the region, APOC sent C. C. Mylles to Doha to negotiate an oil concession with the Shaikh. In August of that year, APOC was granted a two-year exploration license in Qatar. This venture, however,

posed a problem for APOC, as the company had signed the 1927 Jacques LeBlank Photo courtesy of Dr. “Red Line” with a consortium of oil companies called the Iraq Petroleum Company (IPC) to the effect that no member of the consortium would be engaged, on its own, in any exploration activity in the former Ottoman empire of the Middle East, and Qatar was part of the Red Line Agreement. APOC thus informed SAUDI ARABIA IPC of its option in Qatar, and IPC permitted APOC to act as its nominee in Qatar. Late in 1932, APOC dispatched two geologists, E.W. Shaw and P.T. Cox, to Qatar. After a survey during January-March 1933, the team found out that the Dukhan anticline in southeast- ern Qatar shared similarities with the discovery field in Bahrain: Its surface rocks were Eocene limestone and hence good potential for a Cretaceous reservoir rock (like that of Bahrain). The Dukhan anticline was nothing but the highest hills in Qatar, which the natives called Jabal Dukhan (“Hill of Smoke”) for its oftentimes hazy weather. Outcrop of the Dukhan anticline displaying the Middle Eocene Dammam Formation.

geo expro february 2010 43 U.A.E. 30 km history of oil

In 1933-34, APOC dispatched W.E. of Qatar, which took over the concession and Qatar at a Glance Browne and D.C. Ion to precisely map its operations. This new company included BP Land area: 11,437 sq. km (4,416 sq. mi) the Dukhan anticline. After this mapping, (23.75%), Royal Dutch Shell (23.75%), Cie Population: 860,000 (largely immigrants APOC entered a negotiation with Qatar, and Francaise des Petroles (23.75%), Standard Oil from other parts of the Middle East) on 17 May 1935, it was granted a 75-year of New Jersey (11.87%), Mobil (11.87%), and Proven oil reserves: 25.41 billion barrels oil concession covering all of Qatar’s land Paratex (Glubenkian Foundation) (5.0%). Oil production: 843,000 bopd to explore and produce oil. In return, the During the winter of 1937-38, a new group Producing oil wells: 421 Qatar government was to receive a royalty of geologists, Norval E. Baker, T.F. Wil- Crude oil exports: 703,000 bopd of 2 Indian rupees per ton of oil produced, a liamson, and R. Pomeyrol, visited Dukhan Refinery capacity (Umm Said built in payment of Rs. 400,000 on signature, and an to locate a drilling site. They examined the 1953 with an initial capacity of 600 annual sums of Rs. 150,000 (after five years, Dukhan anticline, which was 80 km long bopd): 80,000 bopd Proven natural gas reserves: Rs. 300,000) in addition to the royalty. Two with 90 meters of structural closure in the 25.466 trillion cubic meters (891 Tcf, world’s years later, APOC on behalf of IPC created a Middle Eocene limestone, and recommended third largest after Russia and Iran) new company called Petroleum Department a location for the first well. Gas production: 76.98 billion cubic

meter (Bcm)

f n i h t p Formation e Natural gas exports: 56.78 Bcm OPEC member since 1961

Mauddud Source: OPEC Annual Statistical Bulletin 2008

t e e

eous

iddle

etac

r Nahr Umr

C 5000 Shuaiba

Hawar Qatar flag

Kharaib The Story of Shaikh Mansour All historical oil discoveries in the Middle East included local guides, some of

eous 6000 whom contributed no less than their

etac Yamama bosses to the success of expeditions

r although these men have often gone

er C

o nameless or little known. In the case

L of the Dukhan field, however, we are Sulaiya fortunate to have a report about a man named Shaikh Mansour, who helped the Shaw-Cox survey in 1933 and the 7000 Williamson-Baker survey in 1937-38. Hith Williamson later remarked that Shaikh I Mansour “appeared to have a mental II picture of the whole of Qatar and had III

r a quite uncanny capacity for knowing

IV exactly where he was under all condi-

c i s s a

tions – in clear weather, in fog, or even

r u J r

e Jubaila in darkness.” He ensured that the field p p 8000 U work proceeded smoothly among the local inhabitants; he was also quick to Hanifa learn geology, especially for locating the outcrops of Eocene-age Alveolina Upper (a large foraminifer fossil) limestones in Seal (Evaporite/Marl/Shale)

r Uwainat Qatar. During World War II, Mansour

c i s s a A Carbonate Reservoir Gas Lower went blind from trachoma. Despite this,

Source (Marl) Oil in 1946 he joined N.E. Baker and F.

r u J e l d d i 0 2 km 9000

M Izhara E. Wellings, geologists working for Petroleum Development of Qatar, to Illustration by Rasoul Sorkhabi examine outcrops outside the Dukhan Stratigraphy and structural cross-section of the Dukhan oil and gas field drilled in 1940 (Source, Frei, field. For this new field work, Mansour H.P., 1984, Proceedings of Seminar on Source Habitat of Petroleum in the Arab Countries, OAPEC, took his nephew as his “seeing eye,” Kuwait, pp. 115-123.). The Dukhan field is about 80 km long and up to 8 km wide. At the surface, and still proved to be an excellent guide. the limbs of the anticline dip 2-10°. At the Jurassic reservoir level, the anticline comprises four culmina- tions along strike. Structural closure at the Jurassic horizon is 488 m which increases to 640 m at the He lived in a village near Dukhan until level of the Permian Khuff formation. The deepest well in the field is the 1990 Dukhan DKG-27 which his death in 1972. penetrated the Ordovician sandstone at a depth of 4,975 m.

44 geo expro february 2010 the discovery well Drilling of Dukhan No. 1 began in October 1938. In the last weeks of 1939, the well hit oil shows, not in the Cretaceous limestone (as had been expected with comparison to the Bahrain field) but in the Upper Jurassic limestone, similar to Saudi Arabia’s Dammam field discovered in 1936. In January 1940, Dukhan No. 1 was completed at a depth of 1733 m, and was then producing about 4,480 barrels of oil per day (bopd). The producing reservoir rock, the Upper Jurassic Zekrit Formation, was similar to the

Arab Formation of Saudi Arabia, even having Photo courtesy of Qatar Petroleum the same number of limestone payzones which had been named A, B, C, and D of Arab For- A view of Halul Island (an area of 1.5 sq. km) from where the first shipment of oil produced by Shell mation in the Dammam field. However, N. from the Idd al-Sharqi field was exported on 1 February 1964. Today, the island is home to 11 large T. Langham, the well site geologist, unaware oil storage tanks with a total capacity of 5 million barrels; it also has pumping stations and modern of these payzones discovered two years earlier, loading terminals for tankers. In 2008, oil exported from Halul was about 90 million barrels transported by 137 tankers; operations are managed by the Qatar Marine Crude. called the Zekrit limestones as No. 1, 2, 3 and 4. (Zekrit Formation is named after the port of Zekrit, northeast of Dukhan, where a jetty had been built by the drilling team for un- Khatiyah sector. Production from Fahahil duction averaged about 169,000 bopd. loading materials.) began in 1954 and from Jaleha in 1955. In During 1959-60, deeper wells in the 1955, Dukhan No. 1 began producing water Dukhan field discovered non-associated gas 1940s … so much so that the provincial government from the Permian Khuff formation GEO ( In March 1941, Dukhan No. 2 was drilled designed a man-made oasis. But many other ExPro 04/2009) at a depth of 3,000 m, and about 16 km south of the first well. It dis- wells continued producing oil from. By 1957, this new play added to the hydrocarbon covered oil in the No. 3 limestone and gas in 58 wells had been drilled in the Dukhan, of wealth of the Dukhan oil and gas field. The the No. 4 limestone. In May 1942, Dukhan which 48 wells were producers. In 1959, pro- top of the Khuff formation lies at depths of No. 3 was drilled about 5 km east of the first well. However, World War II (1939-45) put an end to field operations in Dukhan. Indeed, IDD AL-SHARQI Reservoir DUKHAN Dukhan wells and installations were stripped Onshore field NORTH DOME or destroyed in 1942; therefore, after the war ended, the field needed reconstruction. Aptian, 99 m thick Porosity 22-30% Shuaiba Renewed operations began in late 1947. Permeability 0.2-200 mD During the following three years, three Oil 27° API, 2.8% sulfur drilling rigs were continuously employed to Illustration by Rasoul Sorkhabi drill 25 wells. Meanwhile, a 120-km pipeline No Cretaceous payzone Barremian, 174 m thick Porosity 15-30% was built from the Dukhan field to the Kharabi Permeability <12 mD port of Umm Said in eastern Qatar where Oil 27° API, 2.8% sulfur terminal facilities also were put in place. On 31 December 1949, the first shipment of the Kimmerdgian-Tithonian, Kimmerdgian-Tithonian, Dukhan crude was made from Umm Said 27 m thick 30 m thick Arab-3 (C) Porosity 15-20% Porosity 10-23% (Mesaieed) where the tanker S.S. President Zekrit Permeability 30 mD Permeability 50-200 mD Manny carried 80,000 tons of oil to Europe. Oil 37° API, 1.8% sulfur Oil 27° API, 3% sulfur Kimmerdgian-Tithonian, Kimmerdgian-Tithonian, 56 m thick 102 m thick 1950s … Arab-4 (D) By 1950, Qatar was producing 33,800 bopd. Porosity 19% Porosity 10-38% Zekrit The production increased threefold by 1954. In Permeability 70 mD Permeability 1-300 mD 1950, Qatar’s revenue from oil was $1 million; Oil 42° API, 1.1% sulfur Oil 32° API, 1.7% sulfur it amounted to $23 million in 1954, mainly Callovian, 46 m thick Porosity 5-20% because in September 1952, Qatar had signed Upper Permeability 0.1-20 mD a new agreement with the Petroleum Depart- Araej Oil 36° API, 1.2% sulfur Comparison of oil payment of Qatar calling for 50-50 profit-sharing. Bathonian, 60 m thick Bathonian, 55 m thick zones in the onshore The Dukhan field is comprised by three Dukhan field and the off- Uwainat Porosity 19% Porosity 5-20% oil reservoir sectors, Khatiyah, Fahahil, Permeability 16 mD Permeability 1-1600 mD shore Idd al-Sharqi North and Jaleha/Diyab, respectively, from north Oil 43° API, 0.8% sulfur Oil 36° API, 1.2% sulfur Dome field (data after Frei, to south. Early production was from the 1984).

geo expro february 2010 45 history of oil

2835-3262 m, and its thickness varies from Qatar Petroleum 448-564 m. Gas production from the Khuff In 1952, Petroleum Department of Qatar together with Petroleum Department of Oman commenced in 1978. and Dharfur and Petroleum Department of Trucial Coast States (small shaikhdoms between Qatar and the mouth of the Persian Gulf) merged to form the Petroleum Con- offshore qatar 1960s: cessions Ltd under the general-manager of G. Heseldine. enter shell In 1953, with further organizational changes, Petroleum Department of Qatar was In August 1949, the new ruler of Qatar, named Qatar Petroleum Company. Shaikh Ali ibn Abdullah al-Thani (the elder In 1972, the government of Qatar established the Qatar National Oil Company son of the former Emir), gave a concession to manage its oil operations. In 1973, the government took 25% share each of Qatar to the International Marine Oil Company (a Petroleum Company and Shell Company of Qatar. In 1974, the government estab- subsidiary of the Superior Oil Company and lished the General Petroleum Corporation (later called Qatar Petroleum), and signed Investment Corporation) to explore for oil new agreements with the two oil companies giving 60% share to the state-run Qatar offshore Qatar (in waters beyond the 3-miles Petroleum. In 1977, Qatar fully national- line); but the company could not locate any ized onshore and offshore operations and suitable structure for drilling, and thus relin- gave service contracts to the former conces- quished the concession in 1952. sionaries. Qatar, in turn, granted a new offshore concession to Shell Overseas Exploration Company; the concession was transferred in 1954 to a new subsidiary called Shell The Dukhan Field Today Company of Qatar. The concession, covering Dukhan, Qatar’s only onshore oil and gas field, is located about 84 km west of Doha. 25,900 sq km (the equivalent of 4 North Sea Its oil production capacity, according to Qatar Petroleum, is up to 335,000 bopd but quadrants), was for 75 years and included an the actual production is subjected to reservoir management. The total number of wells initial payment of £260,000 to the Shaikh, in the Dukhan field is 605, including 300 oil-producing wells, 182 water injection and a fifty-fifty profit sharing after -produc wells, 58 gas-producing and injector wells; the remaining are shut-in, observational or tion; field operations were bound to start abandoned wells. within nine months and drilling within two Oil and gas from the Dukhan field are separated in four degassing stations: Khatiyah years. Shell started seismic survey in the Qatar North, Khatiyah Main, Fahahil Main and Jaleha. (The Khatiyah, Fahahil and Jaleha waters in the spring of 1953 and drilled two stations were built in 1949, 1954, and 1955, respectively.) The crude is then pumped exploratory wells in 1955 and 1956; both wells to the Umm Bab Booster Station where its pressure is boosted for transportation by were dry. It was only in May 1960 that Shell pipeline to the Umm Said (Mesaieed) port, about 100 km east of Dukhan. discovered the Idd al-Sharqi oil and gas filed, In 1989, water injection in the Dukhan field was started to maintain reservoir some 85 km east of Doha. This field consists pressure. In 1998, a gas recycling plant was started to process 800 million cubic feet of two elliptical domes; the larger North per day of Arab-D gas cap to recover 38,000 bopd of condensate and 750 tons per Dome (which was discovered and produced day of NGL. In 2008, Qatar Petroleum awarded a $140 million deal to French firm first) and the smaller South Dome. CGS Veritas for a 3D-seismic survey of the Dukhan field. This project is expected to be completed by the end of 2011. A new reservoir study of the Dukhan field is also In 1963, Shell discovered another major underway and will be completed in 2012. offshore field, the Maydan Mahzam, with payzones at Arab-D, Arab-C, and Uwainat. Production from this field started in 1965. In 1969, the Idd al-Sharqi was producing 35,000 b/d and the Maydan Mahzam 100,000 b/d. By then, Qatar’s total oil production had increased to 17 million tons (293,000 bopd), earning its government $115 million in 1969. Production from the Idd al-Sharqi in 2006,

according to a report by Qatar’s Ministry of Photo courtesy of Qatar Petroleum Foreign Affairs, was close to 144,000 bopd from the North Dome and 10,000 bopd from the South Dome. Production from the Maydan Mahzam in 2003 averaged 38,800 bopd. Crude produced from these offshore fields were (and are) stored at facilities on the island of Halul (located about 80 km northeast of Doha), which also has pumping stations and loading terminals for tankers. The first shipment of oil produced from the Idd al- Sharqi North Dome field was exported from A view of the new Qatar Petroleum corporate training facility at Dukhan this island on 1 February 1964.

46 geo expro february 2010 geotourism

The Cape Peninsula:

An Ancient Beauty Photo: Jane Whaley

Table Mountain dominates the city of Cape Town. It is one of the oldest mountains in the world and is made up of great thicknesses of Ordovician sandstone overlying the Precambrian shales and granite, the unconformity between them identified by a clear break in slope. It is cut by many deep gorges, the result of erosion along fault and joint planes. It is possible to hike to the top in a couple of them.

48 geo expro february 2010 Jane Whaley

Spectacular, extraordinary, awe-inspiring: Table Mountain and the Cape Peninsula are more than just a list of superla- tives, with much of interest to offer the visiting geologist.

It is surely one of the most iconic views in precambrian turbidites the world, and yet never fails to impress the Much of Cape Town and the coastal plain is visitor: Table Mountain rising steeply and underlain by the 560 million year old Malm- dramatically from the very centre of the city esbury Group of rocks, which are ancient of Cape Town. To the south, the land narrows slump and turbidity current deposits. They still rapidly towards the famous Cape of Good exhibit classic features such as graded bedding Hope, constantly battered by wild seas and and ripples, despite their great age and the sub- fierce winds. The whole area is one of fasci- sequent metamorphism and tight folding they nating diversity in flora and fauna as well as have undergone. They form the base of Table scenery, and at the root of this is, of course, Mountain and rarely outcrop at the surface, An Ancient the geology. but can be seen along the rocky Sea Point With the exception of some Quaternary shoreline on the western coast of Cape Town. and Holocene deposits, the rocks of the The Malmesbury Group also contains vol- Cape are all very old. They comprise three canics, seen as reddish-brown rocks among main groups; the Cambrian-Carboniferous the usually dark slates and sandstones, indi- Table Mountain Supergroup, predominantly cating that the sediments probably accumu- Beauty sandstones; the Cambrian Cape Granite; lated on a tectonically active margin, with and the Precambrian Malmesbury Group, volcanoes developing as oceanic crust was composed of dark grey mudstones and lighter pushed down into the earth under lighter sandstones. Although originating in ancient continental material. times, the way these rocks and the landscape At one time Nelson Mandela and fellow appear today is the result of millions of years inmates of the prison on Robben Island, of constant erosion, deposition, earth move- 10km north of Cape Town and easily seen ments and transformations. from Table Mountain, had a chance to view Photo: Jane Whaley

Hout Bay, 15 km south west of Cape Town, is presided over by the impressive peak of Sentinel Moun- tain, composed of Ordovician Table Mountain Group Rocks. Whales are commonly seen basking in the calm waters of the bay.

geo expro february 2010 49 geotourism

these rocks at close quarters. The core of the the thick layers of mudstones and sand- island is a Malmesbury Group anticline, stones which make up the overlying Table smoothed to a platform by Pleistocene wave Mountain Group lasted over 30 million Photos: Jane Whaley action, and overlain by wind blown sand. years, and the resultant disconformity is very clear, particularly along the spectacular darwin’s eye-opener Chapman’s Peak Drive, south of Cape Town. During the early Cambrian, Malmesbury The Table Mountain Group, part of the Group sediments were disturbed by the intru- Cape Supergroup, was deposited between sion of magma, the result of the continental 510 and 340 million years ago, and the oldest collision which eventually formed the super rocks, the Graafwater and Peninsula Forma- continent of Gondwanaland. The magma tions, form the 600m high sandstone cliffs of cooled and crystallised slowly, in the process Table Mountain. The Graafwater, up to 60m melting and deforming the surrounding sedi- thick, is composed of fining–up cycles of in- ments. Although this occurred at great depth, terbedded iron-rich maroon mudstones and Boulder Beach on the west coast of False Bay is a subsequent erosion exposed the granite at the lighter sandstones, passing conformably into rare mainland nesting site for the African Penguin. surface, forming a base for the deposition of the more massive, relatively iron-free sand- At this location the characteristic round shape the rocks which produced the dramatic cliffs stones of the Peninsular Formation, which of the granite boulders, the result of preferential of Table Mountain and Cape Point. are 700m thick in this area. weathering along The effect of hot magma intruding into These are the only Cape Supergroup rocks Malmesbury Group shales can be clearly seen found in the Cape Peninsula, except at the near Sea Point, south-west of Cape Town. highest point of Table Mountain, where there Over a mere 150m of coastline, the transi- is a very small remnant of the Late Ordovi- tion from undisturbed Malmesbury Group, cian Pakhuis glacial tillite, left by the tail end

through a complex mixed rock known as of a melting glacier. At one time, however, Photos: Jane Whaley migmatite, to homogenous granite, is beauti- the Group probably covered a large percent- fully exposed on a wave cut platform. In 1836, age of Southern Africa, with up to 9,000m of Charles Darwin visited this location, and it sandstones deposited on a passive continen- had a major impact on his thoughts on the tal margin. Tectonism in the Permo-Triassic origin of rocks, as the initially fluid nature of caused them to buckle and fold, forming the the granite is hard to deny. Cape Fold Belt, which extends 600 km from the eastern side of False Bay. The hard, horizontally bedded sandstones of the nine kilometres of sand This folding exposed softer layers at the Ordovician Graafwater and Peninsula Formations, The intrusion of the Cape Granite marked surface, and extensive erosion removed much sitting on a bed of Cape Granite, have withstood the pounding of these churning seas for millions the beginning of the uplift and erosion of of the once continuous Table Mountain of years, but have been eroded to form cliffs ris- the Cape Town area, as the deeply buried Group layer. The nearly horizontal sandstones ing over 200m from the sea. Contrary to popular Precambrian rocks and granite were forced of Table Mountain are the sole remnant of the opinion, the dramatic Cape of Good Hope is not to the surface. The hiatus between these and Fold Belt in the Cape Peninsula, probably rep- the most southerly point of the continent of Africa. Photos: Jane Whaley Photos: Jane Whaley

Chapman’s Peak Drive from Noordhoek to Hout Bay follows the contour of the sharp non-conformi- ty and break of slope between the Cape Granite and the more resistant overlying Table Mountain Group, with weathered granite clearly seen at the The unconformity between the hard Table Mountain Group and the underlying weathered granite is discontinuity. Current and cross-bedding features clearly seen on Lions Head (left peak), as viewed from the top of Table Mountain. To the right of Lions are frequently seen in the Lower Table Mountain Head are the softer outlines of the Malmesbury Group Signal Hill, with Robben Island in the far distance. Group formations

50 geo expro february 2010 geotourism

A Unique Flora The distinctive geology of the Cape Peninsula has brought a unique biodiversity and ecosystem to the region. Table Mountain National Park, covering 250 km2 of Table Mountain and the Cape Peninsula, is home to 2,285 different plant species, and in 2003 it was nominated as a UNESCO world heritage site. Table Mountain alone has almost 1,500 species in a mere 57 km2 – approximately the same number of species as the whole of the UK. The special vegetation of the Cape is known as fynbos, from the Afrikaans meaning ‘fine bush’, and consists of a diverse range of plants, with a large number of heathers, reeds, bulbs and large vibrantly flowering protea bushes, many of which are only found

Photo: Val Taylor Photo: Val in the Western Cape - nearly 70 species of protea are found in the coastal region of Cape Province alone. Fynbos plants are well adapted to the thin, nutrient-poor soils and The King Protea (protea cynaroides) is the national flower of South Africa and is only found strong seasonal rainfall and dry summers of the area. in the Western and Eastern Cape. It takes four The unique ecosystems also extend offshore into False Bay, where the influence of the or five years to flower for the first time and the warm east coast Agulhas current and the cool, west coast Benguela current means that flowers can be 30cm in diameter. over 31% of marine animals and 40% of seaweeds are found no where else in the world.

resenting the trough of a deep fold, where the parts of the Peninsular and the Cape Flats horizontally lying beds were less easily eroded. area. Evidence of these sea level changes can be seen as wave cut terraces along the coast rugged glory around Cape Town.

Prolonged periods of uplift and erosion mean Much of the Cape Town landscape has Photos: Jane Whaley that there is a huge gap in the geological been altered to accommodate the demands record of much of the Cape area, from the of man, and the unique biota of the region end of deposition of the Table Mountain has also suffered major changes. But stand Group in the early Carboniferous right up in the incessant wind at Cape Point, looking to the present day. Igneous activity about over the gloriously rugged landscape towards 130 million years ago (Early Cretaceous) Table Mountain, and you realise that over resulted in a number of black dolerite dykes much of the Cape Peninsula, geology and which cut through the older rocks, but there nature still have the upper hand. The Ordovician Graafwater and Peninsula Forma- was little further sedimentation on land until tions were deposited either in a rapidly flowing fluctuating sea levels during the Pliocene and Acknowledgement: Thanks to Prof John braided river system or as multiple stacked beach Pleistocene ice-ages resulted in the deposi- Compton of the University of Cape Town for as- deposits over muddy lagoonal sediments, and tion of weakly cemented marine sands over sistance with this article current and cross-bedding features are frequently found in these rocks.

Near Sea Point it is possible to traverse exposures of Malmesbury Group shales, hardened and darkened by heat from the intruding Cape Granite (right), before moving into the contact zone, where the shales are distorted and folded by the magma (centre). Walking on, the granite predominates (left), although containing many large xenolithic fragments of metamorphosed country rock, before the granite alone is exposed. All over a mere 150m of coastline. Photos: Jane Whaley

52 geo expro february 2010 ENERGY STATISTICS

Jarand Rystad (M.Sc.) Managing Partner Rystad Energy Does Exploration Create Value - in a Mature Province Like Norway?

Exploration activity was at an value per boe for undeveloped Discounted Cash Flow (DCF) get in total 1.35 billion boe. The all time high on the Norwegian discoveries was USD 2.6 per boe analysis for each discovery, which corresponding value was USD Continental Shelf (NCS) in for this portfolio of 3 unappraised we have done using current 3.4 billion when using DCF 2009, with 67 exploration wells, and 3 appraised discoveries. forward curve. Results ranged based on the forward curve and 45 of which were wildcats and Statoil’s USD 213 million from negative values to USD USD 1.7 billion when using the 22 appraisal wells. Total pre-tax acquisition of 15% of the high 6.4 per boe, with an average of conservative USD 50/boe oil spending was USD 5 billion. quality Goliat field corresponds USD 3.1 per boe when using the price assumption. With after- However, the amount of money to a value of USD 6.2 per boe if forward oil price. We found oil tax exploration cost of USD 1.1 at risk after tax for the compa- the Norwegian Petroleum Direc- fields close to existing infrastruc- billon, we can confirm the overall nies was only USD 1.1 billion, torate resource estimate of 245 ture, like Fulla and Marihøne, picture that one dollar in gives since the government is picking MMboe is used. This analysis or fields with stand alone po- three dollars out. up 78% of the bill through the came after 5 wildcat and apprais- tential like Grosbeak (USD 4-5 For APA licenses, 23 wildcat cash-back rule implemented in al wells were completed, giving a per boe), had the highest value. wells were drilled with 10 finds 2005. likely pre-tax cost of USD 600 Lowest value per boe was for grouped into six discoveries; Is there a risk that the govern- million, after tax finding and ap- small, deep and/or distal gas Grosbeak, Corvus, Gygrid, Luno ment is sponsoring a G&G play- praisal costs of USD 0.55 per boe. fields like Gro in the Norwegian basement, Ragnarrock SW and ground for the oil companies? In Another “appraised” transaction Sea (USD 0.5-1.5 per boe). Harepus. Total volumes are 250 particular, does the new APA- was Lotos’ acquisition of 10% of Combining these methods MMboe and the DCF cash flow regime (Awards in Predefined the Yme Field from Det norske would indicate that unappraised based on the forward curve USD Areas; a yearly round of re-cir- for USD 56 million in 2008, cor- discoveries on the NCS probably 800 million. After-tax finding cost culated acreage) actually create responding to USD 8.2 per boe. have an average value of USD was USD 1.4 per boe, and value of value? A second method of valuing 2.8 per boe. This is the after-tax the discoveries USD 3.3 per boe, Rystad Energy has investigat- discoveries is to look at current value as companies see it, and confirming our numbers above. ed these issues, and has conclud- pricing of pure play Norwegian ex- should be compared with after- Another 21 wildcats were drilled ed that exploration on the NCS ploration companies, of which Det tax finding cost of about around on acreage from regular rounds, of actually creates value with a good norske is the obvious candidate. USD 0.9 per boe. Pre-tax value is which only 5 of the wildcats were margin. For every dollar put into Det norske currently has a market USD 12.7 per boe, which could in acreage award after 2005, result- exploration in the area in recent value of USD 740 million. The be compared with pre-tax finding ing in a surprisingly high success years, you get three dollars back. company holds 115 MMboe in six cost of USD 4.0 per boe. rate of 85% or 18 finds with a total For APA rounds seen separately, primarily unappraised discoveries, Discovered volume at NCS in volume of 1.1 billion boe, worth the return is slightly lower, with corresponding to 45% of the value 2009 is uncertain since the Gro USD 2.24 billion. Finding cost every dollar invested yielding 2.5 of portfolio. This corresponds to a gas discovery field could be small, for these volumes was only 0.6 per dollars in return. For regular con- value of USD 2.9 per boe. large or very large. However, as- boe, again confirming our numbers cession rounds, which primar- The third method is to do signing 530 MMboe to Gro, we above. ily include frontier acreage, the return has been 1:3.5 in recent Value creation from 2009 exploration in Norway USD per boe years. 7 So, how have we reached this Value per boe 6 conclusion? After‐tax cost per boe

5 Average value of One challenge has been to new discovery find a good indicator of the value 4 of recent discoveries. There are 2.5 x return few transactions, and terms and 3 3.5 x return conditions are rarely revealed. 2 However, Wintershall’s USD 1 740 million acquisition of Revus last year is one indication. Revus’ 0 After‐tax cost Value per boe After‐tax cost Value per boe After‐tax cost Value per boe Value per boe Value per boe portfolio consisted of discover- per boe (Forward oil per boe (Forward oil per boe (transaction (Enterprise (transaction price) price) value) value) value) ies like Luno, Astero, Jordbær, APA round 2009 drilling results ‐ Regular rounds 2009 drilling Goliat transaction 2009 Det norske part Revus part ‐ Oselvar, Vega South and Yme. 23 wells; 10 finds results ‐ 21 wells; 18 finds ‐ undeveloped undeveloped finds ‐ valuation finds ‐ Technical resources for these dis- 2010 transaction coveries were 110 MMboe. Thus, value 2008

54 geo expro february 2010 GEOMEDIA Rasoul Sorkhabi

Edwin Drake’s Life and the Early Oil Industry

This well-written book offers the full story of a pioneer oilman, a historic discovery well, and all the players who gave birth to the modern oil industry.

Myth, Legend, Reality - Edwin Laurentine Drake and the Early Oil Industry: William R. Brice. Published by Oil Region Alliance, Oil City, Pennsylvania

On 27 August 1859, a 21-meter oil industry in that region, in- well that “Colonel” Edwin cluding chemists Samuel Kier Drake had drilled into a thin and Benjamin Silliman, and en- Devonian sandstone bed in trepreneurs George H. Bissell, the Oil Creek near Titusville, J.G. Eveleth, Francis B. Brewer, Pennsylvania, hit crude. This Asahel Pierpont, W. A. Ives, discovery well, a famous piece James M. Townsend and others of history (“The Birth of the who founded the Pennsylva- Modern Oil Industry,” GEO nia Rock Oil Co. in 1855 (later ExPro, 03/2009), ushered in the called Seneca Oil). At the end of modern oil industry in the USA the book, important historical and around the world. Nonethe- documents and correspondenc- less, our knowledge of Edwin es are given in appendices, and Drake’s life and well has long the Endnotes and Bibliography helped Drake in this venture in Freedom: The Story of Colonel remained fragmentary. further enhance the value of the was a less-known blacksmith Drake, by the American Petro- Now 150 years later, we have book for interested scholars and and water-well driller by the leum Institute, and the Drake a definite book on the life and researchers. name of William Smith (“Uncle Well Museum and Park in the career of this pioneer man and Edwin Drake was born to Billy”) who put together the first Oil Creek. Now this book takes event. I say “definite” because a farmer family in Greenville, mechanical engine to drill a well Drake’s heritage to bookshelves this new book is a detailed, New York, on 20 March 1819, exclusively to extract oil from around the world. comprehensive, research-based, but grew up near Castleton, underground. The discovery well This new book is a chronicle and well-documented work; it Vermont, where his family was successful because of Drake’s of the pioneer efforts in a region is also profusely illustrated. Its finally settled. Shortly after his resilience and commitment. and a period ripe for oil dis- author, William R. Brice, pro- mother’s death, Edwin, then Drake, however, did not covery. Petroleum (“rock oil”) fessor emeritus of geology at aged nineteen, left the family profit from the oil wealth he replaced whale oil for lamps (and the University of Pittsburgh at farm in search of wealth. He did had created for his bosses (nor thus saved whale population), Johnstown and editor of the Oil- various jobs including working did Uncle Billy). Overall, Drake fueled vehicles to replace horse Industry History, devoted several on a steamer, in a hotel, in a lived as a poor man both before carts and eventually dominated years to researching and writing store, and more importantly as and after his oil discovery well. the world’s energy production this 675-page volume. a conductor on the New York & Only in 1873, the Pennsylvania and consumption. Published by The book begins with an New Haven Railroad. The latter Legislature granted an annual the Oil Region Alliance (www. informative overview of the job gave him a free train pass, payment of $1,500 to support oil150.com), the book will history of oil in the ancient times and it was partly because of this Drake’s and his wife Laura’s life. remain a cornerstone of our (chapter 1) and in the Americas privilege that Drake was hired Even then, his last years were knowledge about this fascinating (chapter two), thus placing the by the Seneca Oil Company to spent in illness and he eventually subject. The low price tag of $40, Drake story in a historical and drill into the oil seeps in Penn- died in Bethlehem, Pennsylvania obviously subsidized by grants, geographic context. The remain- sylvania. Drake was then in his on 8 November 1880. should encourage not only li- ing eight chapters (the “meat” of late 30s, a tall, bearded man who Drake has been honored in braries, universities, and oil com- the book) takes the reader on a wore a black hat and long coat various ways in the past, includ- panies but also individuals (pe- vivid journey through Drake’s (his well-known image from ing a monument at Woodland troleum geoscientists, engineers, life, the nineteenth century photographs of that time). Cemetery in Titusville (where economists, and historians) to Pennsylvania, and all the players Of all folks described in Edwin and Laura Drake were get a copy of this well-written who had a role in founding the the book, one who practically buried), the 1952 movie, Born book.

56 geo expro february 2010 global exploration update CHINA: Deep water gas discovery

Calgary based Husky Energy is one of the appraisal wells confirmed that it ultimately the formation of major sub-basins char- largest foreign holders of exploration blocks could produce more than 150 MMcfgpd. acterised by horst and graben structures. offshore China and has been exploring in Production from the field is expected to Regional subsidence since the Late Oligo- the area since 2002. In 2004 it signed a commence in 2013. cene resulted in a tilted continental shelf contract for the relatively unexplored Block The area around the Pearl River Mouth with thick sequences of fluvial sedimenta- 29/26, which covers nearly 3,000 km2, of Basin experienced two major episodes of tion in the Pearl River Mouth basin, ideal the Pearl River Mouth Basin, approxi- rifting along the South China margin from conditions for the accumulation of hydro- mately 300 km south-east of Hong Kong. the late Cretaceous to the early Oligocene. carbons in multiple reservoirs. The company was rewarded in 2006, when This caused regional normal faulting, with Liwan 3-1-1 found significant quantities of gas. At the time this was the deepest water well drilled offshore China, in depths of 1,345 m. In December 2009 Husky announced another discovery, 23km north-east of

Liwan. Well LH 34-2-1 drilled to a total Photo: GeoPublishing depth of 3,500m and flowed at a restricted rate of 55 MMcfgpd, although eventual production rates are estimated to be in the region of 140 MMcfpd of gas or more. Husky plans to drill an appraisal well on the new discovery early this year to determine its potential further. Little further information about the latest well has been made available, but it extends the trend confirmed by the Liwan discovery, which targeted objectives in the Upper Oligocene Zhuhai Formation and Lower Miocene Zhujiang Formation. Based on interpretation of the 3D seismic data, the Liwan discovery is estimated to contain a contingent resource of 4 - 6 Tcfg (700 - 1,000 MMboe). Liwan is reported to have found 56m of net gas pay in two Tertiary reservoir zones, and recent More gas has been found in the South China Sea.

GHANA: Tweneboa-2 confirms Major Field

Ghana’s exciting story continues with the in stacked reservoir sandstones, deposited in (GEO ExPro No. 5, 2009, p. 66). The country announcement in January 2010 that the an extensive turbidite fan system. The field lies is rapidly pushing towards its first oil produc- Tweneboa-2 appraisal well in the Deepwater in over 1,300m of water, 50km from the coast tion from the offshore, anticipated possibly Tano Basin has identified a significant hy- and close to the border with Cote D’Ivoire. later this year. drocarbon column, confirming Tweneboa as Offshore Ghana has been the site of several Tullow operates the Deepwater Tano major oil and gas-condensate field. major discoveries in recent years, including licence and is partnered by Kosmos Energy The well found a gross reservoir interval of the giant Jubilee Field, which has estimated Anadarko, Sabre Oil & Gas, and the Ghana 153m, including 32m of net hydrocarbon pay upside reserves of nearly two billion barrels National Petroleum Corporation.

58 geo expro february 2010 exploration update The worlds most significant discoveries brought to you by IHS and GEO ExPro Jane Whaley BRAZIL: Billion Barrels Post-salt Discovery

Amongst all the hype about pre-salt discoveries Cretaceous, Albian, Aptian and Barremian. Pre- first well, OGX-1, found about 30m net pay of in Brazil, it would be easy to overlook the largest liminary analysis suggests recoverable reserves oil-bearing Albian carbonate reservoirs. Brazilian private sector offshore exploration across these reservoirs are between 1 and 2 Bbo. Both these wells are still drilling so the campaign, which has been remarkably success- The next well, 1-OGX-3-RJS, about 6km final analysis has yet to be undertaken, but the ful in the post-salt of the Campos Basin. Brazil- from its predecessor in the same block but tar- company believes it is working a very promising ian company OGX Petróleo e Gás Participações geting a different prospect, also found hydro- new play. Overall in the Campos Basin OBX S.A. only entered the industry in June 2007, but carbons, recording an oil column of more than has seven blocks, five of which it has started since then has acquired 7,000 km2 of what it de- 180m and net pay of around 50m in carbonate working on. Within these it has identified 24 scribed as ‘high potential offshore acreage’. reservoirs of the Albian, Aptian and Barremian prospects with prospective resources of 2,562 This analysis seems to be bearing fruit, as sections, with some intervals presenting porosi- MMboe. drilling on OGX blocks in the southern part of ties in excess of 30%. OBX is part of the industrial group EBX, the Campos Basin, which only started late last Based on recently released final test infor- founded by Brazilian entrepreneur Eike F. year, has already lead to a number of interesting mation on this well, combined with the 3D Batista, who has a very successful track record discoveries. seismic data interpretation, OGX estimates in developing new enterprises in the natural re- In October 2009 OGX announced that that recoverable oil from for all reservoirs in sources and infrastructure sectors. 1-OGX-1-RJS, the first well of a seven well this prospect alone is between 500 and 900 programme, had discovered recoverable reserves Mmbo. Potential production rate of the 20° of between 500 MMbo and 1.5 Bbo in block API oil is thought to be in the region of 3,000 BM-C-43. The well is located approximately 85 bopd. And finally, in January wells 1-OGX-4 km off the coast of the state of Rio de Janeiro, and 1-OGX-5, in blocks BN-C-42 and close to the border between the Campos and BN-C-43 respectively, have both reported the

Santos Basins, in relatively shallow water of presence of hydrocarbons. OGX-4, the south- Photo: Diamond Offshore 140m. It was followed by 1-OGX-2-RJS, on a ernmost of these five wells, encountered an oil separate prospect about 15km further north in column of approximately 90m with around 17 BM-C-41, which reached a depth of 3,550m, ms of net pay in Eocene sandstone reservoirs, The 1-OGX-5-RJS in the Campos Basin is being and found high quality reservoir intervals, pre- characterized by excellent levels of permo- drilled by Diamond Offshore’s semi-submersible dominantly carbonates, in the Eocene, Upper porosity, while OGX 5, which lies close to the rig, Ocean Ambassador. USA: north of Baton Rouge in Louisiana, extends Treasure in Davy Jones Locker offshore in deep horizons on the shelf, and this discovery would appear to bear out that The rocks buried at great depth beneath the be flow-tested, but the company reported that hypothesis. waters of the USA Gulf of Mexico continue the sands logged below 8,321m appeared to The Davy Jones discovery well will be to reveal exciting discoveries. New Orleans be “of exceptional quality”. As drilling contin- followed by an appraisal well to the south- based company McMoRan Exploration ued the well found a lower hydrocarbon pool west to test similar sections at slightly shal- focuses on the Lower Miocene sub-salt and with an estimated 20m net pay. lower depths. The company also owns the the ‘deep gas’ post-salt plays in the shallow While no reserve estimates have been an- Blackbeard prospect, on South Timbalier waters of the northern Gulf of Mexico, and nounced yet, McMoRan Exploration has de- Block 168, about 100km to the south-east, recently struck lucky with a well on the large scribed the prospects it is chasing in the Gulf which was drilled to over 9,400m and found Davy Jones ultra-deep prospect on South Coast region as having over 30 Tcf (840Bm3; Miocene-aged sands at that depth. In total, Marsh Island Block 230, about 10 km south 5.7Bboe) gross unrisked potential. The McMoRan has identified about 15 promising of the coast of Louisiana, in only 6m of water. company believes that the Cretaceous section, prospects on large structures on the Gulf of Spudded in June 2009, the well has already productive onshore in the Tuscaloosa trend Mexico shelf, with ties to the deepwater. reached over 8,500m, with a proposed depth It is hoped that the of 8,840m, and is targeting the Eocene Wilcox Davy Jones well will formation, the Paleocene, and possibly Cre- provide evidence to taceous Tuscaloosa formation sands below a link deepwater shelf listric fault. discoveries to the onshore fields. In mid January 2010 the company announced that the well had encountered 41m net of hydrocarbon-bearing sands in four zones in the Wilcox Formation of the Eocene/Paleocene. The reservoirs have yet to McMoRan Exploration Co.

geo expro february 2010 59 Q&A Halfdan Carstens

Possible Oversupply in Ten Years Time

Peak oil will happen, eventually, but possibly not before the 2030s. In the meantime, we may be faced with oversupply, partly driven by increased production in Iraq.

We have 32 people here at Lysaker, just If they succeed in this aggressive ramp-up, Rystad Energy south of Oslo, including my six fellow despite security and political issues and oil Rystad Energy is an independent partners, consultants, analysts and technology service constrains, we might actually go from E&P advisory and business intel- developers. We have been recruiting only top a tight supply situation to temporarily global academic people from Norway and abroad oversupply around 2016-2018, since oil sands, ligence data firm offering global – half of our staff are non-Norwegian. In Brazil, the Caspian and deep water also will database applications, stand-alone addition we have teams in Asia and Trond- come in with significant volume additions. research products and strategy con- heim supporting us on scouting, with focused Majors will control part of this ramp-up, and sulting services. From this edition scouting tasks for companies and regions. might be tempted to prioritize high profit onwards, Rystad Energy will provide projects elsewhere, while Chinese players analyses for our new column “Energy In this edition of GEO ExPro, we are focusing would push for progress. Statistics” (page 54). on the Middle East. How do you foresee the future for the international oil industry in this Finally, Mr Rystad, you sit on a huge data base region? concerning oil and gas reserves, what are your According to our field-by-field forecasts, thoughts about Peak Oil and the future of fossil Rystad Energy has just entered its seventh year we see that Middle East growth might be 6 energy? of operation, meaning that establishing the million bopd towards 2020. This is less than Eventually we will see peak oil, and in our company was a success. How did it happen in the some other prognoses, but still more than database this will be in the 2030s. New un- first place? any other region globally, just ahead of Brazil conventional hydrocarbon resources will have I had conducted a lot of strategy work for and North America. On the gas side, Middle more flexibility in terms of turning activity on international oil companies during my years East growth is even stronger, and Russian and off according to the macro environment. with McKinsey. Often I felt that we spent too levels could be reached in 2020 if markets and Oil prices will see a long term increase in real much time on data gathering and modelling, politics allow it. terms, but we should expect large fluctuations and thought that we could be even more ef- given the dynamic forces in the economy. ficient as consultants by reusing data through Lately, Iraq has come into focus because of ten We will need 20 years of high oil prices to our own global information infrastructure. new contract areas. How will their efforts to boost get sufficient investments and technological Most people thought that it would be totally production from 2.2 MMbopd today to possibly breakthroughs in renewable energy and “clean unrealistic, so I decided to do it on my own. more than 6 MMbopd in 7 years affect the petro- coal”, and this will gradually take over from My old friend Per Magnus Nysveen, previ- leum industry? the 2030s. ously with DNV, also shared this vision, and we started up in my basement six years ago. Jarand Rystad, who So, what is the main product today? Or should holds a M.Sc. degree we say products? in physics from the First and foremost, we are a consulting Norwegian Univer- sity of Science and company providing advice on E&P strategy, technology, founded Photo: Rystad Energy as transactions and oil service markets for our the Norwegian com- clients. pany Rystad Energy in 2004, having gained But you are not only offering consulting services. extensive experience in oil and gas strategy You are also marketing data bases? work through his long Yes, and this is the new thing for 2010, career with McKinsey namely that we are now officially launching & Company. His areas our global upstream database – our UCube – of expertise include ex- with production profiles and financial profiles ploration strategy, concession policies, asset for all fields, exploration blocks and E&P transactions, corporate companies globally. M&A, macro analysis, upstream technology Based on the number of people I can see around and gas infrastructure. your office, you have grown into a substantial company. Tell me about your staff, locally and international!

60 geo expro february 2010 HOT SPOT Rasoul Sorkhabi

Paleozoic Tight Gas Plays in Jordan

Compared to the other Middle Eastern countries, Jordan does not have a significant position in terms of conventional oil and gas resources. According to Oil & Gas Journal Akkas (21 December 2009), the kingdom’s known LEBANON gas field oil reserves are only one million barrels and

S Y R I Y A Illustration: Rasoul Sorkhabi that of natural gas is 213 billion cubic feet. Indeed, Jordan spends one-fifth of its gross domestic product to import 96% of Risha I R A Q gas field its energy needs predominantly from Iraq (Jordan Times, 26 October 2009). Against this backdrop, it is interesting to learn that Amman recently British Petroleum (BP) signed a deal with the government of Jordan to J O R D A N explore and develop the natural gas resourc- S A U D I es of the Risha Basin in eastern Jordan. According to the agreement, signed by ISRAEL A R A B I A Jordan’s premier Nader Dahabi and BP’s exploration chief Michael Day last October, in the first phase of the project, BP will explore Jordan covers a land the area totaling about 7,000 sq. km (the area of 89,342 sq. 0 100 km km, with Amman as equivalent of a North Sea quadrant) along its capital the Jordanian-Iraqi border for 3-4 years at a cost of $237 million. If the exploration yields successful results, BP will then invest 2-3 Tcf (15 September 2008, quoted from Risha Block Stratigraphy US$8-10 billion to produce between 300- Abdulelah Rousan, then director-general 1,000 million cubic feet (mcf ) per day. Cur- of Jordan’s National Petroleum Company, Quaternary rently the Risha gas field produces 21 mcf NPC). Eocene from 20 wells. If all goes well, the Jordanian government Paleocene Exploration of the Risha basin began in will receive 50% of the produced gas, with the mid-1980s with seismic shooting (9,057 the other half going to BP and NPC. This Tectonic Illustration: Rasoul Sorkhabi Cretaceous Inversion km) and exploratory drilling by Jordan’s will significantly boost Jordan’s natural gas Natural Resources Authority. Seismic and electricity production. Currently there is Mid. Jurassic images showed horst and graben structures an electric power plant in the Risha field. in the Paleozoic section. The Paleozoic In 2000, an international consortium Triassic sediments dip and thicken eastward while headed by BP negotiated with Jordan to the overlying Mesozoic sediments thicken build a gas pipeline from Jordan via Syria to Permian toward west and dip under the Basalt Lebanon. But the proposal was suspended Plateau. The total sedimentary thickness in after the government decided to focus on Silurian the Risha basin exceeds 7,000 m. Risha-1 further exploration of the Risha basin. In source

(3177 m total depth) and Risha-2 (3314 m) the same year, the NPC in collaboration (rift) margin

~7,000 m in thickness Ordovician were drilled in 1984 followed by Risha-3 with Geoquest (a division of Schlumberger) tight gas (4204 m) which discovered gas in Ordovi- conducted a detailed study of the Risha gas cian sandstones. Since then, dozens of wells field. Cambrian have been drilled; many are dry but some The Risha gas field is located 270km wells produce gas. The Risha field delineated northeast of Amman. What amplifies the Infracambrian passive Paleozoic to be 1500 sq. km in area produces from importance of the Risha field is that it shares Ordovician tight sandstone at depths of a similar geologic history with the little-de- Proterozoic 2425-2575 m with thin beds (2-12 m each) veloped Akkas gas field, some 200 kilome- Basement in faulted glacio-fluvial channels. Its proven ters further east in Iraq. Indeed, the Paleozo- Not to scale Rasoul Sorkhabi (2010) gas reserves are 180 billion cubic feet (Bcf ) ic section thickens eastward up to 6,500 m. (equivalent of 34.2 MMbo) (Oil and Gas It appears that the deserts of eastern Jordan Acknowledgements: Journal, 2 July 2007). However, estimates and western Iraq have a great potential for I thank Nicola Dahdah for helpful geologic of total gas reserves in the field range from Paleozoic tight gas plays awaiting systematic information. 400 bcf (Jordan Times, 12 March 2000) to exploration.

62 geo expro february 2010 100 50

0 1861 1900 19502000 $2004/barrel GLOBAL RESOURCE MANAGEMENT Historic oil price oil Historic equivalents oil of Sm million (16 barrels Recoverablereserves 100> field Major oil of Sm million (80 barrels Recoverablereserves 500> field Giant equivalents Sm million (800 barrels billion 5 > Recoverable reserves field Supergiant 10 x 1 Trillion= 10 x 1 = Billion 10 x 1 = Million Numbers m 1.9 = NGL tonne 1 m 1000 Energy ft 1 m 1 gas Natural barrels 7,49 = tonne 1 m 0.159 = barrel 1 m 1 oil Crude FACTORSCONVERSION 3 = 0.028 m 0.028 = 3 3 = 35.3 ft 35.3 = = 6.29 barrels 6.29 = equivalents 3 gas = 1 m 1 = gas 3 3

9 12 6 3 3

o.e 3 o.e. 3 3 ) ) 3 ) of oil of ) million million HOT SPOT giant Rumaila field (discovered by BP in the in BP by (discovered field Rumaila giant BP and CNPC laid their hands on the super succeeded. bid one Only Round). Licensing (Iraq’sfields gas and oil 8 First for Petroleum auction an hosted government Iraq’s when from 1.34MMbopdin2003. 2008,up in 2.4MMbopd to risen has output daily Iraq’s then, Since 240,000bopd. about Iran.with war The low”was time 1991 in “all his started Hussein PresidentSaddam before year a 1979, in 3.5MMbopd about was oil of production maximum Iraq’s production. decades threeand exploration country’s the hampered have past the over Iraq in events 2008. Arabia for its part produced 10.8MMbopd in million barrels 10 of oil than produced more every day. in Saudi result eventually may that areas contract 10 was rounds the of outcome Saudi Arabia within the next 5 – 10 years. The with par on nearly power oil an into country the turn certainly almost will year last Iraq andtechnically.financially both assist to companies oil foreign invite to necessary been has it potential, (!) huge the change,advantageof full take orderto in and to war. about of is years manyThis following tatters in remains industry petroleum Iraq’s redevelopingexistingfields. companies thatwillnowstart from today’s oil level,thankstocontractswithmajorinternational In lessthan10yearsIraq’s oiloutputmayincrease3or4times Iraq More oiltocomeinwar-torn BP StatisticalReview ofWorld Energy operating conditions.” and economic current under reservoirs known from years future in recoverable be to certainty able reason with demonstrate data engineering and geological which oil of quantities estimated ”The Proved reserves The licensing process started last summer last started process licensing The Despite its rich petroleum resources, violent in held rounds licensing petroleum Two - troleum Licensing Round). The combined oil combined The Round). Licensing troleum Pe Second (Iraq’s auction next the of results the targeted plateaus. reached having after 3.3MMbopd produce to expected are fields these tively. Together respec Qurna, West and Zubair develop to Mobil/Shell Exxon and Eni both with deals talking aboutthis “oily” country. a plateauof2.85MMbopd. ment is to increase production until it reaches commit fields. The oil largest world’s the of one is such as and 65Bbo as much as contain 1950s!) close to Basra in southern Iraq. It may resource base.resource 28-34, for in depth knowledge of Iraq’s petroleum Petronas) bothhave targets of1.8MMbopd. (Shell,Majnoon and (Lukoil,Statoil) Qurna for these areas totals close to 5MMbopd. West production plateau target players.The tional Statoil,addi as TPAOand Kogas Gasprom, Lukoil,Japex, Sonangol, Petronas, with east Iraq, south- discovered in1976)were thelargest. in supergiant (another Majnoon and 1973) in Iraq, discovered southern in field ant Bbo, of which West Qurna, phase 2 (a supergi reserves in the fields were estimated at about 41 n eebr w wr ifre o the of informed were we December, In Later,November,in made government the when numbers big to used get Weto have Please refer to GEO ExPro No 3, 2009, pp. 2009, 3, No ExPro GEO to refer Please awarded, then were areas contract Seven

Photo: Arlo K. Abrahamson and CNPC. BP of assistance the with redeveloped be now will field The Freedom. Iraqi Operation of stages early the in fire on set was field oil Rumaila the 2003, In Halfdan Carstens Rasoul Sorkhabi ------