The
Millennium Atlas: Petroleum geology of
the
central and northern North Sea
-
a major new publication - by
Dan Evans, Colin Graham and Heather Stewart
As
you read this in the Autumn 2002 edition of the Edinburgh Geologist, you may be
somewhat surprised at the title of this article. You probably think that most
things related to the Millennium are by now things of the past, are completed,
or are perhaps even falling into disrepair. But the Millennium Stadium in Cardiff
remains a place where visiting rugby teams are treated with excessive courtesy,
and the end of 2002 will see the publication of the Millennium Atlas.
The Atlas describes the geology for the UK (largely
Scottish if you will), Norwegian and Danish sectors of the central and northern
North Sea (see map), with a slant towards the petroleum aspects.
This is the first attempt to describe the geology of the North Sea Basin across
these national boundaries, and is a consequence of the co-operation of the Geological
Society of London, the Norwegian Petroleum Society and the Geological Survey of
Denmark and Greenland (GEUS). These organisations together formed the not-for-profit
Millennium Atlas Company Limited (MACL) with the sole purpose of producing and
distributing the Atlas.
Make
no mistake, it will be a big book in full-colour A2 format with about 400 pages,
so that it will weigh about 9 kilograms. For those not feeling too strong it will
also be available in CD-Rom format. It will have 458 Figures (many of them comprising
multiple diagrams, and we haven't counted them all yet), a list of about 1600
references, and each chapter will have an appropriate full-page frontispiece image.
An example of a diagram is shown in Figure 2, but remember
that full colour will be used throughout the Atlas itself. The
atlas will be printed in Haddington by Scotprint; the large size of the
Atlas means that the pages will have to be hand-stitched as machines would not
be able to cope. We understand that the book will be produced at a rate of 5 copies
per day. It has been suggested that it is not so much a coffee-table book, but
with the addition of four legs could be made into a coffee table!
The idea for producing such an Atlas came from Paul Bathurst
of Exploration Geosciences Limited, a small consultancy company that has worked
extensively in western Canada where they had found a major atlas to be invaluable
for their oil-exploration work. Paul considered that the production of a comparable
atlas would be a good way to mark the Millennium at a time when the North Sea
had become a mature oil province (the Atlas specifically excludes the southern
North Sea gas province). However, Paul might perhaps have been a little more circumspect
in calling it the Millennium Atlas given that the Canadian atlas took seven years
to complete! In 1997 he began to raise sponsorship for the production of such
an atlas, and the Atlas now has full sponsorship from 35 oil companies (even if
some of them no longer exist due to several recent mergers) and lesser support
from a number of others. At that time, the
oil industry was flourishing, so that Paul was able to raise sponsorship pledges
from a large number of oil companies, and also their commitment to helping produce
chapters for the Atlas. It was then evident that the project was feasible, and
it was at this stage in 1998 that MACL was set up, and Andrew Armour, at that
time Exploration Director of Enterprise Oil, became the Chairman of the Company
and a driving force for the project. Subsequently the main contracts were let
to Exploration Geosciences Limited for Project Management, the British Geological
Survey (BGS) for Editing, and Lovell Johns Limited for Book Production.
After an Introductory chapter, the Atlas has three structural
chapters that outline the tectonic evolution of the broad north-east Atlantic
region, describe the deep crust beneath the North Sea, and provide the structural
framework for the Atlas area. There then follow 12 stratigraphic chapters before
chapters on petroleum generation and formation waters. The Atlas ends with chapters
on exploration history and the resources of the basin, followed by the extensive
list of references, a glossary to help those not familiar with some terminology,
and an index. The project was set up so
that individual companies or small groups of companies were responsible for writing
chapters and producing the associated illustrative material. In some cases this
work was contracted out or other experienced groups of workers were brought in
to help; in fact BGS were contracted by Murphy Petroleum to write the Oligocene
to Holocene chapter, and the lead author was none other than your very own Editor
of this estimable booklet. It was well into 1999 before all chapters had been
properly allocated authors, and the progress of the project was not helped by
the slump in oil price that resulted in many oil-industry geologists, including
authors of the Atlas, losing their jobs. Each chapter was provided with a broad
outline framework and a standard set of stratigraphic tops for each stratigraphic
chapter.
| A
few facts and statistics that emerge for the Millennium Atlas area are:
The first well to find oil
was in the Danish sector in 1966, in chalk. The
first UK oil discovery was in 1969 at what is now the Gannet Field, but it was
not economic to extract oil from that well until over 30 years later in 1997.
The deepest well drilled
is to 6085 m. The
total of recoverable hydrocarbon reserves is 12,500 million m3 of which
43% have been produced. About
40% of the total reserves are in Lower and Middle Jurassic reservoirs.
Statfjord is the largest
oilfield, and Troll the largest gas field. | A
total of 92 authors and a further 62 contributors have produced the chapters,
and a great deal of work has also been done by the draughting personnel supporting
these groups. Each chapter has been externally refereed, involving a total of
60 referees. After resubmitting the chapter following refereeing (some chapters
were reviewed twice), the editing work really began. Although there was a great
deal of overlap, Dan dealt mainly with the text and Colin with the diagrams; Heather
joined at a later stage to finalise work on the references, glossary and related
work. After the diagrams had been marked up by Colin, they were sent to the wonderfully
named draughting company 'Could-you-Just?' where Cathy Hickey co-ordinated the
standardisation of all the figures. It has
been an objective of the Atlas to maximise the overall consistency of approach
by all the authors; a difficult task given the number involved and the ranges
of data from which they would be working. To help with this, a number of workshops
were held for the authors, the most notable of which was a 3-day residential meeting
at the wonderful field-centre premises of Chris Cornford's Integrated Geochemical
Investigations at Bideford in Devon where a good time was had by all.
Producing the Atlas has been a long, if most rewarding,
haul, and as we write this in late August, there is a very intense period of work
to ensure that the material is delivered to the printers on time to ensure that
copies are avaialble for a series of launches of the Atlas in early November.
And the last chapter was not even completed by the authors until the end of July!
The finalising of the layouts is being worked on by Jon Gammage at Lovell Johns'
offices near Witney. We are greatly looking forward to a little trip to Haddington
to see the presses rolling... Oh, there is one
other small point; you will want to know how much it costs and how you can buy
it. It is published by the Geological Society of London, and will cost you a mere
£199, or £149 if you are a member of that, or a related society. We
believe that the CD-Rom, being produced by Lynx, will be similarly priced.
We very much hope that you will like it.
Bibliographic reference: Evans,
D., Graham, C., Armour, A., & Bathurst, P. (editors and co-ordinators) 2003.
The Millennium Atlas: petroleum geology of the central and northern North Sea.
The Geological Society of London. Figures
The area covered by the Millennium Atlas is shaded.
The Atlas does not cover the southern North Sea and
the
area west of Shetland is also excluded
return
to bookmarked text
A figure from the Millennium Atlas This
is an image of one specific horizon in the Cenozoic at a depth of several hundred
metres below the sea bed. It has been produced through the use of 3D-seismic data,
that is individual seismic profiles collected on a very close grid such that a
'cube' of data is collected. Once a horizon has been picked on the individual
profiles, a variety of images of that horizon can be computer-generated. Seismic
data and recent improvements in its acquisition, processing and interpretation
techniques, have been very important to the exploration and production history
of the North Sea. This image shows the pattern of polygonal faults in a mudstone
interval.
return
to bookmarked text
Dan
Evans has worked in offshore geology for over 30 years, following up a PhD study
by joining the marine group at BGS. He has produced several offshore maps and
was lead editor of the UK Offshore regional reports. He has been involved in the
Millennium Atlas project from the start.
Colin
Graham was brought into the Atlas project to act as diagrams editor once the authors
had begun to produce their chapters. For this, his knowledge of IT, added to his
considerable marine geological experience, has been invaluable. Heather
Stewart joined BGS less than a year ago after graduating from Glasgow, and has
been thrown in at the deep end (including 1600 references!) in helping with the
Atlas.
|
