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Flashbacks on the first discoveries of oil fields in the Middle East.
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.
An inventory of petroleum source rocks in the world’s major sedimentary basins show that six intervals in the Earth's Phanerozoic history provided organic-rich sediments generating over 90% of world's conventional oil and gas discovered so far. Here we explore this issue.
Large-scale volcanism caused by a superplume in the mantle was possibly responsible for wide-spread deposition of excellent source rocks in Mid-Cretaceous times.
Understanding the deposition of evaporites and how the subsequent deformation history can influence salt basin petroleum systems is crucial for successful resource exploration.
New approach makes geophysical results available to engineers in a form they can use. History matching, volumetric calculations and reserve estimates may all be improved.
Rifting caused the breakup of Western Gondwana into two separate continents and is responsible for the key elements of a mega petroleum system that is now being fully exploited.
The sub-salt discoveries recently reported in the Santos basin, offshore Rio de Janeiro, Brazil could be the largest in over 30 years and has captured the world's attention.
Salt structures come in every possible shape and stretch our imagination.
This means difficulties in seismic imaging, but it also means that the innovative explorationist can look for spectacular traps.
The innovative Virtual Seismic Atlas has now been launched. This is a major contribution
to teaching, training as well as research – and paves the way for further progress in the geosciences.
Seismic imaging is considered key to reduce risk and cost in exploratory as well as development drilling. Although we have recently seen important advances, the authors claim that a step change is required to significantly improve the industry’s ability to obtain accurate seismic images of oil and gas reservoirs within geologically complex settings.
By combining this information with our present
geophysical understanding of the area, it may be
possible to give more refined prognoses of the
subsurface development and economic potential
of analogous structures in this extensive but still
little explored hydrocarbon province.
Cave technology, designed for aiding seismic interpretation, is
opening new windows on the understanding of rocks in the field.
Exploration interest in the deepwater US Gulf of Mexico is at an all time high following the discovery,
in 2001, of thick Paleogene submarine turbidite sands in the Baha #2 well. See the seismic.
From being a tool mainly for the prediction of petroleum maturation,
basin modelling has become a fundamental process in almost
all aspects of the analysis of petroleum systems.
Interest in this huge geological province has grown strongly over the last few years
following the development of the Snøhvit field, the discovery of the Nucula field
earlier this year and a genuine belief that there is more oil and gas to be found where
both multiple source rock horizons and reservoir layers have been proven.
See Fugro's 2D seismic data -
Read the article
Could a single plant species have really changed the earth from a greenhouse world
towards the modern icehouse state – and what are the implications of this for both
petroleum exploration and climate change?
Historic drilling and production data can be used to enhance exploration strategies
focused on stratigraphic and subtle combination traps. Stratigraphic and subtle combination
traps are those which cannot be defined by
structural closure alone.
North Sea Renaissance (NSR) is an ongoing long offset 2D seismic program that will total
some 85,000 km at the end of this year. The program is acquired with a cable length of 8,000
m, while data processing is optimised for the purpose of deep imaging and AVO capabilities.
The Norwegian Sea continental margin is dominated by the deep-water Vøring and Møre basins, which contain thick Cretaceous and Tertiary fills. To the east lie the Halten Terrace, Nordland Ridge and Trøndelag Platform, with a cover of Triassic, Jurassic and Cretaceous sediments.
The Norwegian Sea covers more than
200 000 km2 of highly prospective acreage
with many proven discoveries of Mezosoicand
Cenozoic age. The large shelf area
can be divided into three sub-regions.
With 12 recently announced deep-water discoveries and an aggressive leasing schedule for the Western and Central Gulf of Mexico, exploration and production technology is being pushed to its limits.
Despite previous disappointments, geologists can now demonstrate the probable presence of prolific source rocks, good reservoir rocks and huge structures in an area that is now open for licensing.
Lots of sediments – and plenty of oil. The Niger Delta, situated in the Gulf of Guinea, formed at the site of a rift triple junction related to the opening of the southern Atlantic.
Highly permeable sand bodies injected into low permeability shales may provide additional reserves to existing discoveries and fields if properly recognized. Such sandstones, a product of postdepositional remobilisation,may also constitute exploration targets in their own right when thick and laterally continuous.
Based on recent advances in plate tectonics, sedimentology and sequence stratigraphy, I suggest that the Earth is affected by relatively short-lived episodes of increased tectonic activity separated by longer intervals of relative quiescence.
GeoPublishing, c/o NGU 7491-TRONDHEIM, NORWAY +47 73904090 / +47 90563595
