GEOSCIENCE EXPLAINED
The Gulf of Mexico Phase 3 Phase 2
Exploration interest in the deepwater US Gulf of Mexico is at an all time high with the deep water “Wilcox” sand Map showing extent of the Deep Focus seismic survey.
Deep Structure Phase 1 is shown in blue. Planned Phase 1
play being the main reservoir target. phases 2 and 3 areas shown in grey Bouguer gravity over Phase 1.
0.00 0.00 0.00 0.00
0.000
0.00-1000.00 -1000.000
-1000.00-100
Bjørnøya Basin Bjørnøyarenna Fault Cmplex Loppa High Hammerfest Basin
0.00-2000.00 -2000.000
-2000.00-200
0.00-3000.00 -3000.000
-3000.00-300
Top
Top Salt Salt
0.00-4000.00 -4000.000
-4000.00-400
0.00-5000.00
Salt
Base Base Salt -5000.000
-5000.00-500
0.00-6000.00 -6000.000
-6000.00-600
0.00-7000.00 -7000.000
-7000.00-700
Base Creataceous
0.00-8000.00 -8000.000
-8000.00-800
0.00-9000.00 -9000.00-900
-9000.000
Top Wilcox
Top Wilcox
-10000.00
0.00 -10000.00
-100
-10000.000
Mid Cretaceous Unconformity (MCU)
Mid Cretaceous Unconformity (MCU)
-11000.00
0.00 -11000.000
-110
-11000.00
-12000.00
0.00 -12000.000
-120
-12000.00
-13000.00
0.00 -13000.000
-130
-13000.00
Acoustic Basement
Acoustic Basement
-14000.00
0.00 Permian Carbonats -140
-14000.000
-14000.00
-15000.00
0.00 -15000.00
-150
-15000.000
-16000.00
0.00 -16000.000
-160
-16000.00
-17000.00 40
0.00 GEO ExPro Desember 2007 GEO ExPro Des ember 2007 -170
-17000.000
42 -17000.00
H o u s t o n , Texa s
GEOSCIENCE EXPLAINED TECHNOLOGY EXPLAINED
G e o r g e R . B r ow n C o n ve n t i o n C e n t e r
Deep Structure: Strength through
integration in the deepwater Gulf of Mexico
Exploration interest in the deepwater US Gulf of Mexico is at an all time high following the discovery, in
2001, of thick Paleogene submarine turbidites sand in the Baha #2 well. This ‘Wilcox’ sand play has now
Coming Soon
expanded across most of the deepwater and is the main reservoir target. These reservoir targets are typi-
cally 3 and 4 way structural closures, obscured by a thick allochthonous salt canopy and cored by deep
allochthonous salt.
Other potential deepwater plays include tionship underneath salt and enabled us
the Late Jurassic Norphlet aeolian dune to trace some of these anomalies back
play and the Upper Cretaceous submarine under salt where seismic imaging is more
fan play in the Western deepwater Gulf. of a challenge.
These potential plays combined with the The new interpreted magnetic basement
Wilcox play ensure that the deepwater sec- was constructed using standard depth-
tor will be an important exploration target to-basement techniques. This quantitative
for many years to come. This was further analysis of the magnetic data was primarily
reinforced by the record-breaking MMS carried out by means of Werner deconvo-
lease sales for the Western and Central Gulf lution, Euler deconvolution and Peters half
of Mexico in 2007 and it is clear that the slope methods. Gravity data was used to
industry is looking to the sub-salt Wilcox help resolve areas of discrepancy between
play and other potential sub-salt plays as the basement surfaces prior to finalizing
the future of exploration in the region. the integrated basement surface.
Understanding these play-fairway
opportunities requires a regional, structural Constraining basement
and stratigraphic context for the Paleo- This integrated basement, together with
gene Wilcox including sub-salt sediment top and base allochthonous salt horizons
distribution and a better understanding of from the Deep Focus work outlined above,
the tectonic framework of the basement.
Moreover, mapping the structure of the
were then used as the cornerstone for 2D
and 3D gravity and magnetics inversion
February 7 - 8, 2008
rifted basement will progress our under- Image of a 2D gravity and magnetic model using 2ModTM. and forward modeling work. Again this
standing of its impact on sedimentation, integration has lead to a much better con-
the distribution of autochthonous salt, and strained basement for assigning density
the location of the Continental-Oceanic each dataset can be interpreted in isolation and susceptibility values.
Boundary (COB). and used as a stand-alone product, integra- Fugro has also developed a workflow Prospects
Despite the huge volume of seismic data tion of these datasets has lead to a better to distinguish basement signal from auto- Producing Properties
(2D and 3D) acquired in the region, one understanding of the sub-salt section and chthonous and deep allochthonous salt U.S. Onshore & Offshore Plays
of the most fundamental challenges fac- has produced a robust and comprehensive signals during the 3D modeling process. International Opportunities
ing the industry is the problem of sub-salt interpretation. The new interpretation and All of this work has lead to a new under-
Capital Providers
imaging. Even with the latest processing modeling results provide a solid platform standing of the morphology and structure
Infinite Networking
technologies, seismic imaging of the sub- for future exploration and research in the of the basement and sub-salt stratigraphy
Expecting 1,500 Booths & 15,000 Attendees
salt stratigraphic section is problematic due sub-salt arena. in the area of Phase 1 that could not have
to the Allochthonous salt canopy. The new integrated basement interpre- been achieved from using seismic data
“Deep Structure”
tation relies heavily on the seismic data
outboard of salt where seismic imaging
alone. The implication of all of this is that as
we move into planned Phases 2 and 3, the Register online at: www.napeexpo.com
The purpose of “Deep Structure” is to is best. This area has been called the cali- lessons learned and the techniques devel-
combat the sub-salt imaging problem by bration area and is the best area to com- oped will allow Fugro to better cope with
using an integrated approach. By integrat- pare the magnetic basement and acoustic the inevitable complexities that will be C a l l N A P E h e a d q u a r t e r s a t 8 1 7 . 3 0 6 . 7 1 7 1 f o r m o r e i n f o r m a t i o n.
ing long-offset (10km) Deep Focus seismic basement without the influence of a salt encountered as we work through Garden
data, high resolution marine gravity data canopy. Banks, Green Canyon and East Breaks.
and high resolution airborne magnetics In the calibration area we have looked We have also have also learned about The 2008 NAPE Expo is presented by NAPE Expo LP, comprised of
data, Fugro has significantly increased its at the relationship between acoustic base- the power of integration and its impor-
understanding of the sub-salt geology of ment and magnetic basement anomalies. tance in geophysical and geological inter- AAPL, IPAA, SEG and AAPG as limited partners.
the Deepwater Gulf of Mexico. Although This allowed us to better assess the rela- pretation.
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