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MEETINGS REPORTS

1. The 3rd PESGB/HGS International Conference on African E&P“Africa: The Continent of Challenge and Opportunity”

This third Conference followed two previous PESGB/HGS meetings on the same theme held inLondon and Houston in 2003/4. It was was opened by PESGB Chairman Steve Boldy who welcomed the350-odd delegates, and then we went straight into the technical programme. The first session on NorthAfrica got underway with an excellent talk by Robin Crawford (BP) on the huge future gas potential ofAlgeria and adjacent basins. David Boote then focussed in on the Ghadames (or Hamra) Basin whoseoutput is currently dwarfed by prolific neighbours but which may yet prove to be substantial. GeoMarkthen gave an overview of their work on North African oil families. In the next paper which was crammedwith detail, T. K. Barsoum discussed the hundreds of millions of barrels of recently discovered oil in theSirte Basin, which have revitalised a basin which many thought was mature. This was followed by a look atsome “real rocks” from field-based research by Nadine Mader (Manchester University). Concluding thesession, Bob Downie gave a block-specific account of work in the Nile Delta,

After lunch, Kevin Burke (Houston University) gave an entertaining synthesis of the entire African continentand its petroleum potential in only 20 minutes. Then Richard Bray (ECL) outlined how tough it can betrying to find oil and gas in continental Botswana and Namibia. Moving north, Dean Griffin (Amerada) gavean overview of the Central African rifts from Benin to Sudan.

William Bosworth (Marathon) then gave a well-researched presentation on the Red Sea Rift, a talkwhich however only touched on the region’s petroleum potential. Adding to the pleasing mix of academicand petroleum geology, Colin Reeves (Earthworks) showed a striking computer animation of continentaldrift on the east coast of the continent. We witnessed the break-up of Pangea and closure of Tethys, andthe journeyof the Indian subcontinent to collide with Asia. The rather unenviable task of following thishigh-tech animation fell to Michael Rego (Aminex) whose presentation described oil shows and seeps inEast Africa. Moving south, Mike Cope (Western Geophysical) gave an interesting and thought-provokingoverview of Tanzania and Mozambique, with abundant high-quality seismic.

Day Two openned with a paper with perhaps the best title of the conference : “Deepwater Africa – what’sleft? where is it? who is going to get it? how much is it worth?”, questions which were surely on the minds ofmost of the delegates. This was followed by excellent papers on Mauritania co-authored by a seven-manteam from Dana, and offshore Cote d’Ivoire by Vanco. Then K. Nibbelink (Devon) presented an enticingaccount of prospectivity offshore Ghana.

Some might have thought that attempting the whole of the deepwater Niger Delta was a tall-order fora 20 minute slot, but Seye Fadahunsi delivered a clear and competent talk with data from his ECL co-authors. Then M. J. Roberts gave an overview of Chevron’s detailed work on this prolific province. The laststop on the pan-continental tour before lunch was the application of some new technology (i.e. AVO) toan old area (the shallow Niger Delta) by Peter Mikkelson (Simco).

After lunch, Ian Davison (Earthmoves) began by presenting a wide-ranging introduction to the SouthAtlantic rift and salt deposition, entertainingly using an animated geological map. This was neatly followedby details of how the PSDM technique is helping improve sub-salt earth models (Steve Henry et al.). Thenext presentation by Garry Karner was memorable and given in an energetic style fuelling the subsequentdebate which was welcomed by the audience. He proposed a rifting model of continental crustal thinningwhich, if correct, would be fatal for all South Atlantic deepwater syn-rift plays, invalidating the thesis of theprevious speaker. This was the only talk to significantly overrun, but the audience happily voted that thedebate should continue into the break.

Mark Smithard gave an excellent presentation on behalf of ChevronTexaco & Sonangol on the explorationhistory of offshore Cabinda, full of subtle field discoveries found by a combination of good geology andgeophysical analysis. Andrew Hopkins (Cardiff University) introduced us to Namibia, using new seismic datajust released on the Walvis Basin. In the final talk, Anthony Greer (OHM Surveys)described electromagnetic

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(EM) sounding and touched on its potential use in Namibia and elsewhere. Questions from the floor, andalso one of the conference poster presentations, made it clear that this alternative technique is receivingattention by several groups who recognise potential commercial applications.

This was a well-organized Conference for which the HGS/PESGB and the convenors should becongratulated. One senior explorer visiting from North America said that the event was now one of two“must do” conferences in his calendar each year.

Kevin DaleSasol, Londonkevin.dale@sasol.com

2. Sedimentary Basins of LibyaThird Symposium: Geology of East LibyaNovember 2004, Benghazi, GSPLAJ

This conference was organized at great expense and with much care by the National Oil Corporation(NOC) of Libya, in order to draw attention to the hydrocarbon potential in the east of this petroliferouscountry, long since over-shadowed by the Sirt Basin since the second well ever drilled found the giant AsSarir field. Speakers from oil companies, consultancies and academia were flown in from every continentin order to provide depth and balance to a packed three-day schedule of mostly parallel sessions. I admitto skipping the palaeontology, hydrology and geophysics when I had to make a choice. That the conferenceitself and all the travel, accommodation and banquets went so smoothly and agreeably is a great credit tothe organisers. Regarding content, to those familiar with this part of the world, there was little new,unfortunately but not unexpectedly. Because of its geopolitical situation as something of an inadvertentbackwater, there has been no exploration drilling onshore here for over twenty years, an incomparablesituation anywhere else circum-Mediterranean. Nor is there is much appreciation locally of the massiveadvances made in the last two decades just across the border in Egypt.

So, recent palynostratigraphic treatises aside, we did not really expect many new data points to berevealed from the sub-surface, but rather the re-working of older data to generate new ideas and newinterpretations from the field and remote sensing. Cruel but true, and as true of my own presentation (onthe relevance of Western Egypt to Eastern Libya) as to many others. I think we can say now with confidencethat we know the stratigraphy, reservoir disposition and source rock geochemistry here sufficiently well tojustify a massive exploratory drilling campaign. We just need the geophysics and not just seismic.

For my part, the first symposium highlight was provided by Prof. El Hawat (Garyounis Univ. Benghazi)who gave a most articulate talk on the subtle clues that, properly interpreted, can help unravel the complextectonic history of the Jebel el Akhdar during the Paleogene, and their implications for nummulitic build-ups. The exposition from Neil Frewin (Shell, Rijswijk) on the role of typing the multitude of oils from theeastern Sirt Basin was compelling, as it used geochemistry as an exploration tool to point us towards someof the under-explored terraces along the limit of the eastern Sirt Basin with the Cyrenaica Platform.

The “German school” (Drs Klitzsch, Lüning and Herzog) reminded us that there is still so much to belearnt from careful study in the field, especially in the Kufra Basin. The biggest surprise of the conferencefor me was the obvious case made by recent Kufra seismic for preserved half-grabens of Infra-Cambrianin the depths of the basin. Adel Moustafa (Ain Shams Univ., Egypt) deserves a special mention for his workon “Syrian Arc” structures in the eastern Western Desert of Egypt, very much a classic “compare andcontrast” exercise from the Libyan point of view.

Mention should also be made in passing of the posters and contractor exhibits. The former by andlarge provided hard copy for many of the verbal presentations, a notable exception being the large montagesof Palaeozoic stratigraphy and structure across North Africa presented by Jonathan Craig and the London-based Maghreb Petroleum Research Group.

I cannot finish without mentioning the “man of the match”, the quintessential larger-than-life ProfessorCelal Sengör. His presence was not constrained by his exciting and all-encompassing talk on the “plate

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tectonics of everything”. I don’t know if it’s true, but someone told me the expression “arm waver” wascoined to describe Prof Sengör in action. Extremely erudite and stimulating, it did all seem to fit and shuffleabout together most convincingly. I look forward to his next contribution appearing, perhaps even here inthis Journal.

In the huddles around the baklava and sweet tea, and formally in the end-of-symposium session, it wasclear that everyone was ready for some move, some change, that would permit exploration to re-starthere. Many large companies were conspicuous by their absence, so it is clear that this area is not everyone’scup of “shay”, but for everyone else, the mood was one of: “When can we get started ?”, and in earnest.Perhaps the NOC did too good a job, and has made a rod for its own back !

Martin KeeleyBogotá, Colombia

“The Geology of NW Libya”

With the lifting of sanctions against Libya, and the opportunity for American oil companies to return toLibya for the first time since 1986, the appearance of these volumes is very timely. They contain informationon both the onshore and offshore basins of northwest Libya, in a format similar to that of the firstsymposium on the Sirt Basin, published in 1996. Fifty-eight papers have been selected out of a total of 120presented at the symposium. Unfortunately some important papers did not make it to publication, but thecontributions presented here form a fair cross-section of the papers given at the symposium. They covera wide range of disciplines from remote sensing to igneous geology, but not surprisingly, the main focus ofattention is on petroleum geology. The papers have all been refereed and edited and the volumes areproduced to a high standard with many colour illustrations.

The papers are grouped according to subject rather than by area, and although the quality of the papersis variable, some very interesting new data is presented. For petroleum geologists in western Libya at thepresent time, there are three or four highly topical subjects: the precise nature of the Ordovician glacialdeposits, the distribution and maturity of the Silurian “hot” shales, the origin of the large volumes of gas inthe northwestern offshore, and the prospectivity of the hinge zone between the Ghadamis and Sirt Basins.All of these topics are addressed in the book, and a great deal of new data has now been made available.

The Ordovician glacial deposits form the subject of several papers. El Hawat and others applied theprinciples of sequence stratigraphy to the Memouniat Formation, and produced a new interpretationwhich divides the formation into two distinct sequences separated by a major sequence boundary. This hasprofound implications for petroleum exploration, particularly in the northeastern Murzuq Basin. Geologistsfrom Total and ENI studied outcrops of both the Memouniat and Hawaz Formations on the Qarqaf Archand present detailed sedimentological models for these formations. In the Ghadamis Basin, for the firsttime we have detailed dating of the Cambro-Ordovician succession, thanks to the palynological zonationof Vecoli and colleagues.

The distribution and maturity of the Palaeozoic source rocks in western Libya forms the subject of apaper by Sikander and colleagues from Sirte Oil. This work reveals the presence of an unexpected sourcekitchen on the Atshan Saddle, which separates the Ghadamis from the Murzuq Basin. The validity of theirvery high heat flow assumptions is debatable, and this source kitchen could surely not have survived theAustrian reactivation of the Qarqaf Arch, but the analysis is important from the standpoint of migrationtiming and direction. The paper also attempts to quantify the volumes of hydrocarbons generated fromboth the Silurian and Devonian source rocks and is an interesting exercise in estimating how little oil hassurvived to the present day. Luning and others reveal that in addition to the basal Silurian hot shale asecond Llandoverian-Wenlockian hot shale is present in some areas, and Storch and Massa demonstratethe biostratigraphic value of the early Silurian graptolite faunas.

BOOK REVIEW