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3D forward modelling of the impact of sediment transport and
base level cycles on continental margins and incised valleys
DIDIER GRANJEON
Department of Geology-Geophysics-Geochemistry, IFP Energies nouvelles, 1 à 4 avenue de Bois,
Préau, 92852 Rueil-Malmaison, France
ABSTRACT
This paper describes a 3D stratigraphic forward model, Dionisos, intended to reconstruct
the stratigraphic architecture of sedimentary basins at a regional scale. This model
accounts for basin deformation, clastic and carbonate supplies and sediment transport,
both in continental and marine environments. Sediment is defined as a mixture of
several grain-size fractions; and the transport of each grain-size fraction is controlled by
a slow creeping law and a faster linear slope-driven and non-linear water-driven diffusion
law. Attention is focussed on sediment transport laws. Passive-margin and source-
to-sink theoretical models were built using independent data from the XES 02 flume
experiment. A few quantitative metrics were defined to analyse the numerical experi-
ments, such as the number of channel per strike sections, the location of the centroid and
erosion and sedimentation rates in the source or transitions areas. These numerical
experiments demonstrate that a non-linear water-driven diffusion equation could be
used to predict the evolution of sedimentary systems under extreme forcing conditions
such as extreme sea-level variations. These applications at a regional scale are very
encouraging, although more studies are required to calibrate transport parameters. The
long-term and short-term evolution of the shoreline and centroid of sedimentary systems
could be investigated. The detailed internal architecture of sedimentary units could be
simulated; such as progradation and downlap of foresets, backstepping and fluvial
onlap, subaerial truncation and incised valleys. These applications illustrate that a 3D
stratigraphic forward model based on a simple non-linear water-driven diffusion
approach could be used at a basin scale to better understand evolution of depositional
systems and thus reduce uncertainties in exploration and reservoir risk assessment.
Keywords: stratigraphic forward model, diffusion equation, passive margin,
incised valley, source-to-sink.
INTRODUCTION
basin (Swift & Thorne, 1991; Helland-Hansen &
Martinsen, 1996; Catuneanu et al ., 2009).
Geologists have followed different approaches
to understand the evolution of sedimentary sys-
tems at a basin scale. Outcrops and subsurface
data (e.g. Porebski & Steel, 2003; Uroza & Steel,
2008), modern systems and natural experiments
(e.g. Wright & Nittrouer, 1995; Tucker, 2009) and
flume experiments (e.g. Heller et al ., 2001; Muto &
Steel, 2001, 2004; Postma et  al ., 2008; Strong &
Paola, 2008; Martin et al ., 2009; Paola et al ., 2009)
have been used to propose process-response mod-
els of continental margins (Porebski & Steel, 2003;
Catuneanu et  al ., 2009; Helland-Hansen, 2009).
These huge amounts of data and concepts have
Frontier exploration areas such as deep-water to
ultra-deep-water environments, arctic basins or
subsalt sedimentary formations have the least
geological information recorded about them
as they are remote basins and difficult to image
or drill. Exploration and development of
such  complex areas requires accurate predic-
tion  of sedimentary system characteristics and
petroleum potential. Sedimentary architecture
is the result of the complex interplay between
accommodation space created in the basin, sed-
iment supply brought into or produced in the
basin and transport of sediment within this
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