Analogue and numerical forward modelling of sedimentary systems; from understanding to prediction

Analogue and numerical forward modelling of sedimentary systems; from understanding to prediction Utrecht, 9 – 11 October 2003 Analogue and numerical forward modelling of sedimentary systems; from understanding to prediction 9 – 11 October 2003 Abstract Volume -1- Analogue and numerical forward modelling of sedimentary systems; from understanding to prediction Utrecht, 9 – 11 October 2003 Sponsors : SHELL Research Rijswijk NITG-TNO Utrecht University NSG IAMG International Mathematical Geology International Sedimentologists Association Association -2- for of Analogue and numerical forward modelling of sedimentary systems; from understanding to prediction Utrecht, 9 – 11 October 2003 Contents Contribution Page POROSITY PREDICTION THROUGH MICRO-SCALE SIMULATION OF GRAIN REARRANGEMENT 7 ALBERTS, L 7 2D AND 3D SUBSIDENCE ANALYSIS IN A COMPLEX FORELAND BASIN: THE VENETIAN BASIN (NE ITALY) .8 BARBIERI C 1 & GARCIA-CASTELLANOS D 2 8 QUANTITATIVE 3D MODELING OF SEDIMENTARY TRANSPORT MECHANISMS IN THE PERIALPINE FOREDEEP (UPPER MARINE MOLASSE, LOWER MIOCENE) .10 BIEG, U.1, SUESS, M.P.1, KUHLEMANN, A 1 & THOMAS, M 2 10 MODELING ALLUVIAL DEPOSITS .11 BRIDGE, J 11 LIMITS TO PREDICTABILITY ARISING FROM NON-LINEAR AND CHAOTIC BEHAVIOUR: RESULTS FROM A NUMERICAL STRATIGRAPHIC FORWARD MODEL OF CARBONATE SYSTEMS 13 BURGESS, P.1 & EMERY, D.2 13 FROM QUINCUNX TO DELTA: A STOCHASTIC CELLULAR AUTOMATA APPROACH TO THE CREATION OF FANS, VOLCANOES AND DELTAS 14 BURROUGH, P 14 MODELLING OF THE MIDDLE TO LATE PLEISTOCENE RHINE-MEUSE SYSTEM IN THE CENTRAL NETHERLANDS 15 BUSSCHERS, F.S & VAN BALEN, R.T 15 THREE-DIMENSIONAL MODELLING OF THRUST-CONTROLLED FORELAND BASIN STRATIGRAPHY .16 CLEVIS, Q 16 MODELLING THE STRATIGRAPHY AND PRESERVATION POTENTIAL OF MEANDERING STREAM DEPOSITS .17 CLEVIS, Q & TUCKER, G 17 NUMERICAL AND ANALOGUE MODELLING OF SEDIMENTARY BASIN FORMATION 18 CLOETINGH, S., GARCIA-CASTELLANOS, D., TER VOORDE, M & SOKOUTIS, D 18 FORWARD MODELING OF MEANDERING CHANNELIZED RESERVOIRS 19 COJAN, I., LOPEZ, S & RIVOIRARD, J 19 PALEOZOIC BASIN STUDY: STRUCTURE, STRATIGRAPHY AND QUANTITATIVE MODELLING IN THE SOUTHERN CANTABRIAN MOUNTAINS, NW-SPAIN .20 DIETRICH, B .20 QUANTIFIED CARBONATE PLATFORM DEVELOPMENT: THE ROSENGARTEN TRANSECT (MIDDLE TRIASSIC, DOLOMITES) 21 EMMERICH, A 21 -3- Analogue and numerical forward modelling of sedimentary systems; from understanding to prediction Utrecht, 9 – 11 October 2003 INCORPORATION OF NUMERICAL AND PHYSICAL FORWARD MODELLING INTO UNCERTAINTY ANALYSIS METHODS 22 FEURER, J., & VAN DER ZWAN, C.J 22 ROLE OF FLUVIAL TRANSPORT DURING OROGENESIS: NEW NUMERICAL AND ANALOGUE MODELLING TECHNIQUES .23 DANIEL GARCÍA-CASTELLANOS, KATARINA PERSSON, DIMITRIOS SOKOUTIS, IVONE JIMENEZ-MUNT 23 A STRATEGY FOR AUTOMATED INVERSION OF PROCESS-BASED MODELS .24 GEEL, C.R.& WELTJE, G.J .24 3D SIMULATION OF SEDIMENTARY FACIES: APPLICATION TO LANGHIAN REEF BUILDUPS IN VALLÈS-PENEDÈS BASIN (CATALUNYA) .25 GRATACOS, O 25 STRATIGRAPHIC FORWARD MODELLING OF DEEP MARINE SYSTEMS USING SEDSIM 26 GRIFFITHS, C 26 THE TECTONIC EVOLUTION OF THE NORTHERN NORTH SEA FROM THE MID-JURASSIC FORM 2D SUBSIDENCE ANALYSIS 27 HANNE, D 27 FINE-SCALE FORWARD MODELLING - EXAMPLE FROM A DEVONIAN REEF OF THE CANNING BASIN 28 MODELLING TURBIDITY CURRENTS BY CFD SIMULATIONS 29 HEIMSUND, S.1, 2, HANSEN, E.W.M.3, BAAS, J.H.4 & NEMEC, W.1 29 FORWARD MODELLING & PREDICTION OF AEOLIAN SYSTEMS USING FUZZY LOGIC, CONSTRAINED BY DATA FROM RECENT AND ANCIENT ANALOGUES 30 HERN, C.1, NORDLUND, U.2, ZWAN, C.J VAN DER1 & LADIPO, K 3 30 USING SUB-REGIONAL SCALE FORWARD MODELS TO CONDITION RESERVOIR-SCALE STOCHASTIC SCENARIOS 31 HERN, C., LAMMERS, H., BURGESS, P & NIJMAN, M 31 INVESTIGATION OF GRAVITATIONAL MASS TRANSPORT PROCESSES - USING THE DISTINCT ELEMENT METHOD AS A MODERN TOOL IN SEDIMENT TRANSPORT MODELLING 32 HUHN, K & KOCK, I .32 MODELLING CYCLES OF FLUVIAL AGGRADATION AND DEGRADATION USING A PROCESSBASED ALLUVIAL STRATIGRAPHY MODEL 33 KARSSENBERG, D.1, BRIDGE, J.S.2, STOUTHAMER, E.1, KLEINHANS, M.G.1 & BERENDSEN, H.J.A.1 33 CHANNELISED TURBIDITY CURRENTS: NEW INSIGHTS INTO FLOW STRUCTURE AND SECONDARY CIRCULATION .34 KEEVIL, G 34 PREDICTING DISCHARGE AND SEDIMENT FLUX OF THE PO RIVER, ITALY SINCE THE LGM 35 KETTNER, A.J & SYVITSKI, J.P.M 35 MODELLING BEDDING AND PETROPHYSICAL CHARACTERISTICS OF TIDAL HETEROLITHIC RESERVOIRS USING A PROCESS-ORIENTED APPROACH .43 MARTINIUS, A.W .43 TECTONIC CONTROL ON PAST CIRCULATION OF THE MEDITERRANEAN SEA 44 MEIJER, P.1, SLINGERLAND, R.2 & WORTEL,R.1 44 -4- Analogue and numerical forward modelling of sedimentary systems; from understanding to prediction Utrecht, 9 – 11 October 2003 NUMERICAL MODELING OF THE SEDIMENTARY SYSTEMS OF LARGE-SCALE COASTAL SYSTEM TRACTS 45 NIEDORODA, A.W., REED, C.W.1, DAS, H.1, DONOGHUE, J.2, FERRAGHAZZI, S.2 , WANG, Z.B.3 & STIVE, M.4 45 3-D PHOTOREALISTIC MODELS OF GEOLOGIC OUTCROPS, A TOOL TO COLLECT QUANTITATIVE DATA; METHODOLOGY AND HISTORIES EXAMPLES IN UTAH AND WYOMING 46 OLARIU, C 46 UPSCALING THE TIME PARAMETER IN STRATIGRAPHIC SIMULATION MODELS: EFFICIENT USE OF HIGH-MAGNITUDE LOW-FREQUENCY EVENTS 47 OVEREEM, I.1 & STORMS, J.2 47 ANALOGUE MODELLING AS A TOOL FOR INVESTIGATING CAUSALITY IN ALLUVIAL STRATIGRAPHY .49 GEORGE POSTMA 49 2D SUBSIDENCE MODELLING OF MIDDLE TRIASSIC CARBONATE PLATFORM DEVELOPMENT IN THE LOMBARDIAN ALPS (ITALY) 51 SEELING, M .51 THE COMMUNITY SURFACE-DYNAMICS MODELING SYSTEM: AN ENVIRONMENT FOR DEVELOPING, SHARING, AND USING SEDIMENT MODELS 52 SLINGERLAND, R .52 AVULSION, AUTOGENIC OR ALLOGENIC CONTROLLED? .54 STOUTHAMER, E & BERENDSEN, H.J.A .54 VARIATION IN DIP OF LATERAL ACCRETION SURFACES IN SUBRECENT FLUVIAL DEPOSITS, PANNONIAN BASIN, HUNGARY: A REFLECTION OF CLIMATIC FLUCTUATIONS OR JUST MEANDERING EXCURSIONS? 55 SZTANÓ, O 1 & MÉSZÁROS F 2 .55 THE ROLE OF NUMERICAL SEDIMENTARY PROCESS MODELS IN HYDROCARBON EXPLORATION AND RESERVOIR CHARACTERIZATION 60 TETZLAFF, D 60 MODELS THAT TALK BACK 61 TIPPER, J.C 61 MODELLING THE IMPACTS OF CLIMATE CHANGE ON EROSION, SEDIMENT PRODUCTION, AND LANDSCAPE EVOLUTION 64 TUCKER, G .64 SCALED MODELS OF SYNTECTONIC SEDIMENTATION – REVIEW OF PRINCIPLES AND FIRST RESULTS 65 URAI, J.L & KUKLA, P.A 65 OUTCROP AND SEISMIC CONSTRAINTS FOR 3D NUMERICAL STRATIGRAPHIC FORWARD MODELING .66 VAN BUCHEM, F., GRANJEON, D & ESCHARD, R .66 IMPACT OF DISCHARGE AND SEDIMENT FLUX ON BASIN MARGIN ARCHITECTURE: AN EXPERIMENTAL APPROACH 68 VAN DEN BERG VAN SAPAROEA, A.P., POSTMA, G & DALMAN, R 68 -5- Analogue and numerical forward modelling of sedimentary systems; from understanding to prediction Utrecht, 9 – 11 October 2003 HIGH RESOLUTION 3D FORWARD STRATIGRAPHIC MODELLING OF CRETACEOUS CARBONATE PLATFORM SYSTEMS 70 VAN DER ZWAN, C.J.1, MASSE, J.-P.2, BORGOMANO, J.1, 2, LAMMERS, H.1 & FENERCI-MASSE, M.2 .70 COMBINATION OF STRUCTURAL BALANCING, REVERSE BASIN AND FORWARD STRATIGRAPHIC MODELLING: SOUTHERN CANTABRIAN BASIN (NW-SPAIN) 72 VESOLOVSKY, Z .72 NON-UNIQUE SEQUENCE STRATIGRAPHIC ARCHITECTURES 73 WALTHAM, D., UDOFIA, M & NICHOLS, G 73 INSIGHTS INTO CARBONATE PLATFORM DROWNING MECHANISMS USING STRATIGRAPHIC FORWARD MODELING 74 WARRLICH, G & BURGESS, P.M 74 MODELLING SOURCE ROCK DISTRIBUTION AND QUALITY VARIATIONS: THE NEW OF-MOD 3D TECHNOLOGY 75 ZWEIGEL, J .75 -6- Analogue and numerical forward modelling of sedimentary systems; from understanding to prediction Utrecht, 9 – 11 October 2003 Porosity prediction through micro-scale simulation of grain rearrangement Alberts, L Delft University of Technology, Department of Applied Earth Sciences, Mijnbouwstraat 120, 2628 RX DELFT, The Netherlands, l.j.h.albert@citg.tudelft.nl Reservoir quality is commonly quantified in terms of the spatial distribution of porosity and permeability, where the latter critically depends on the former Analytical methods of porosity prediction in natural sediments are not available, on account of the difficulties of describing the geometrical arrangement of multi-sized particles of irregular shape Available techniques to estimate porosity are empirical equations that predict an exponential decrease of pore volume as a function of effective stress, or focus on cementation processes Such methods do not incorporate uncertainty or variability of estimates, because they are tailored to data collected in a specific area A more generally applicable method of porosity prediction is needed to enhance the usefulness of process-based stratigraphic simulators for reservoir modelling We have developed a numerical model that simulates the compaction of particle populations at a micro-scale The model comprises the interparticulate mechanics that occur after deposition and during shallow burial, i.e prior to the phase in which chemical processes start to dominate compaction Spatial continuity of the particle pack is simulated through the use of periodic boundary conditions in X and Y, whereas elastic boundaries ('cushions') are implemented in the Z direction The particle pack thus represents an infinite layer of limited thickness, much like a single lamina The grain-size distribution of the pack is the key parameter in the model The model is object based, which allows the mechanics of each particle to be calculated, whereas the properties of the entire pack serve as global state variables during the rearrangement With this model we can simulate realistic trajectories of porosity decline for natural particle-size distributions under several burial scenarios Calibration of the model to physical experiments and sensitivity analyses will be discussed, to provide a basis for the evaluation of uncertainty in model predictions The resulting particle pack can be used for simulations of permeability, conductivity and wave-propagation studies -7- Analogue and numerical forward modelling of sedimentary systems; from understanding to prediction Utrecht, 9 – 11 October 2003 2D and 3D subsidence analysis in a complex foreland basin: The Venetian Basin (NE Italy) Barbieri C 1 & Garcia-Castellanos D 2 1 Department of Earth Sciences, University of Pavia, via Ferrata 1, 27100 Pavia, Italy, chiara.barbieri@manhattan.unipv.it 2 Department of Tectonics, Vrije Universiteit, de Boelelaaan 1085, 1081 HV Amsterdam, The Netherlands The Venetian basin (NE Italy) is characterized by a complex geometry due to the partial superposition of three foredeeps, different in both age and polarity, associated to the development of the surrounding belts, namely the Dinarides, the Eastern Southern Alps and the Northern Apennines, which underwent their main orogenic phases through Tertiary time Therefore, it represents an interesting area to observe and better understand the interplay between the evolution of mountain belts and the response of the adjacent foreland The main goal of this work is to recognize and quantify the contribution of surface loads (i.e mountain belts, initial water depth, sedimentary infill) and of possible deeper-sourced (hidden) loads, to the subsidence observed in the basin This study constitutes the base for the analysis of the sedimentary infill To this purpose, a former 2D flexural numerical modelling is applied along two key transects trending NE-SW and N-S respectively, and a 3D flexural analysis is also performed to solve possible misfits occurring in the sectors which have been influenced by the combined effect of mountain belts Geological and geophysical data concerning the surrounding belts have been collected from literature In particular, data recently published in the context of the TRANSALP project, together with previously available information on both subsurface and surface studies, provide an accurate data set to study the effect of the Eastern Southern Alps on the Venetian basin Moreover, interpretation and depth conversion of seismic lines and paleobathymetric analyses have been performed in this work on some industrial transects and wells respectively (courtesy of ENI), to integrate and improve the already existing data Two dimensional forward modelling has been performed according to the numerical method discussed in Zoetemeijer et al (1990) Gravimetric curves have been also calculated to provide an independent constraint to test the reliability of the models, which show the present geometries occurring in the basin The model calculated on the basis of NE-SW transect aims to test the flexural effect of the Dinaric belt which underwent the main orogenic phases during Paleocene-middle Eocene The best fit has been obtained for a continuous plate condition and an Effective Elastic Thickness value varying along section Nevertheless, the tectonic phases occurred afterwards with different direction make difficult to match all the points representing the base of the Dinaric foredeep -8- Analogue and numerical forward modelling of sedimentary systems; from understanding to prediction Utrecht, 9 – 11 October 2003 The second model, calculated along the N-S trending section, is focussed on the flexure related to the main orogenic phases of the Eastern Southern Alps (late Miocene-early Pliocene) In this case a good fit has been obtained for a broken plate condition and a constant Effective Elastic Thickness value of about 20 km The resulting calculated flexure is strongly influenced by the initial water depth and no hidden load was needed to fit the observed flexure unlike a previously proposed model (Royden, 1993) In spite of the good fit in front of the Eastern Southern Alps, a few metres high forebulge is expected to the South from the model but it is not observed in the present Adriatic Sea In order to better understand the meaning of this mismatch, 3D modelling has been applied by means of the software tao3D (Garcia-Castellanos, 2002) To this purpose, flexure of the plate has been analysed in two steps by progressively adding the loads due to the Eastern Southern Alps and the Northern Apennines Results show that a forebulge form in the same area as predicted by the 2D model if the Northern Apennine load is not taken into account Subsequently this bulge is shifted to the South by the Apennine load and it migrates eventually toward the Dalmatian region by including hidden loads, which are necessary to fit the flexure presently observed in front of this belt In conclusion, on the basis of the calculated models, a forebulge would exist at the end of Miocene in the area corresponding to the present Venetian coastline, which subsequently migrated as a response to the Apennine-related flexure This suggests also that the Apennines would have affected the area of Venice since at least Pliocene – early Quaternary Garcia-Castellanos D (2002) Interplay between lithospheric flexure and river transport in foreland basins Basin Research, 14, 89-104 Royden L (1993) The tectonic expression slab pull at continental convergent boundaries Tectonics, 12, 2, 303-325 Zoetemeijer, R., Desegaulx, P., Cloething, S., Roure, F and Moretti, I., 1990 Lithospheric dynamics and tectonic-stratigraphic evolution of the Ebro Basin Journal of Geophysical Research, 95, B3, 2701-2711 -9- Analogue and numerical forward modelling of sedimentary systems; from understanding to prediction Utrecht, 9 – 11 October 2003 Quantitative 3D modeling of sedimentary transport mechanisms in the peri-Alpine foredeep (Upper Marine Molasse, Lower Miocene) Bieg, U.1, Suess, M.P.1, Kuhlemann, A 1 & Thomas, M 2 1 University of Tübingen, Department of Geoscience, Sigwartstr 10, 72076 Tübingen, Germany Ulrich.bieg@uni-tuebingen.de 2 Technical University of Dresden, Institute for Planetary Geodesy At the Aquitanian-Burdigalian boundary the Molasse basin was flooded by a shallow tide- and wave- dominated seaway, linking the Rhône Basin through, the peri-Alpine foredeep with the Vienna Basin and thus with the eastern Paratethys Mass balancing of sediments derived from the developing alpine orogen and the foredeep suggests a major export of sediments towards the West during the Upper Marine Molasse (OMM, Burdigalian) Therefore it is of great interest which paleoceanographic processes were involved and potentially controlled the westward-directed transport The widespread occurence of meso- to macrotidal facies successions in the Molasse Basin adverts that tidal activity was a major force driving paleocurrents The aim of our study is therefore to provide a numerical model of sediment particle transport conditions within a shallow-water environment We use QUODDY to model paleocurrents in this shallow foredeep QUODDY is a Fortran implementation of a 3-D finite-element shelf circulation model by the Dartmouth College (Lynch & Werner, 1991; Lynch & Naimie, 1993; Lynch et al (1996) It is a free-surface, tide-resolving model based on conventional 3-D shallow water equations Atmospheric forcing terms for wind stress and temperature flux can be implemented, as wells as point source terms for rivers and adjacent alluvial plains Further boundary conditions of the tides in the Paratethys were obtained by calculating an initial tidal mode, based on a 1-degree reconstruction of the global bathymetry in the Miocene Based on paleogeographic data derived from Martel, Allen & Singerland (1994) and new published palaeogeographic maps of the alpine foredeep by Kempf & Kuhlemann (2002) we constructed an irregular triangular mesh with a varying grid resolution, to describe the paleobathymetry of the basin First successful benchmarks were obtained by comparing with the model of Martel et al (1994) Kuhlemann, J., Kempf, O (2002): Post-Eocene evolution of the North Alpine Foreland Basin and its response to Alpine tectonics; Sedimentary Geology, Vol 152, pp 45 – 78 Lynch, D.R., Werner, F.E (1991): Three-dimensional hydrodynamics on finite elements Part II: Non-linear time-stepping model; Int Numer Meth Fluids., 12, pp 507-533 Lynch, D.R and Naimie C.E (1993): The M 2 tide and its residual on the outer banks of the Gulf of Maine; J of Phys Oceanogr., Vol 23 Lynch D.R., Ip, J.T.C., Naimie, C.E., Werner, F.E (1996): Comprehensive coastal circulation model with application to the Gulf of Maine; Continental Shelf Research, Vol 16, No.7, pp 875-906 - 10 - Analogue and numerical forward modelling of sedimentary systems; from understanding to prediction Utrecht, 9 – 11 October 2003 Models that talk back Tipper, J.C Geologisches Institut, Albert-Ludwigs-Universität, Albertstrasse 23B, D-79104 Freiburg, Germany, john.tipper@geologie.uni-freiburg.de 1) Each model that a scientist makes of a system is an expression of a particular set of ideas These ideas - they can be dignified by the terms ‘hypothesis’ or ‘theory’ depending on the amount of evidence that exists to support them - are expressed in the model in a form in which they can readily be worked with; this form may be physical, or mathematical, or graphical, or even verbal There are two reasons for expressing ideas in this way Either it may be hoped that experimentation with the model will help in understanding the structure and function of the parent system, or it may be believed that the model can predict how that system will behave under specified input conditions Understanding and prediction can aptly be described as the twin goals of scientific modelling 2) Understanding clearly must precede prediction, but how can a system ever be known to be understood - or at least be known to be well enough understood to allow a model of it to be used for prediction? There is a range of answers to this question, from the principled to the pragmatic The principled answer is that a system should be taken to be understood only when it can be fully represented in terms of fundamental physical laws The pragmatic answer is that a system can be taken to be understood as soon as any model has been made of it that can be shown to predict how it will behave for a wide range of specified input conditions The principled position allows modelling only for the purpose of prediction; the pragmatic position allows modelling both for prediction and for understanding 3) Modelling for prediction is carried out when a system is judged to be well enough understood that a model of it can be used for prediction for the particular set of input conditions that is of interest - this judgement is of course often entirely self-serving Modelling for understanding is carried out when a system is judged not to be well enough understood Modelling for understanding takes two forms: the testing of the ideas expressed in a model, and the exploration of the consequences of varying a model’s assumptions or parameters Modelling that involves testing is essentially deductive in its nature - as is modelling for the purpose of prediction; modelling that is exploratory can be inductive or deductive, depending on the conditions under which it is carried out 4) The standard strategy employed when models are used for testing involves running the model and its parent system under identical input conditions; the behaviour of the model is then compared to the behaviour of the system If the behaviour of the model is identical to that of the - 64 - Analogue and numerical forward modelling of sedimentary systems; from understanding to prediction Utrecht, 9 – 11 October 2003 system, the confidence that the modeller has in the correctness of the ideas expressed in the model is increased; if the behaviour of the model differs from that of the system, the confidence in the correctness of those ideas is decreased This strategy is attractively simple and is therefore widely used Its simplicity is deceptive, however, and problems inevitably arise whenever it is implemented in practice The most substantial of these are: (1) the problem of adequate access to a model’s parent system, (2) the problem of judging the significance of differences in behaviour, and (3) the problem of allowing for nonuniqueness These problems are particularly acute for the types of models with which earth scientists commonly try to work – i.e for field-scale models of natural systems operating over long periods of time 5) It is helpful to characterise models in terms of the degree to which they are logically identical to their parent systems A model that is logically identical to its parent system is one for which the system is fully understood and for which the input state is always known A model that is not logically identically to its parent system has free parameters or auxiliary hypotheses; the free parameters might be being used to make up for deficiencies in the basic understanding of how the system works, and the auxiliary hypotheses might be being used to make up for lack of knowledge about the system’s input state A model that is logically identical to its parent system does not require testing; it can be used immediately for prediction, for all of the allowable input states A model that is not logically identical to its parent system needs at least some testing; it can nevertheless also be used for prediction, for some input states The amount of testing that a model needs is measured by the proportion of input states for which the model cannot be trusted to show the same behaviour as the system itself; the amount of prediction possible from that model is measured by the proportion of input states for which the model can be trusted The relationship between the amount of testing needed and the amount of prediction possible is shown schematically in Figure 1, as a function of the extent to which a model and its parent system are logically identical 6) The testing-prediction relationship curve defines two distinct styles of modelling One style (below the curve) is modelling that is inherently incapable of being critical - it is what Medawar has termed ‘academic play’ It tests models less frequently than is necessary, it uses them for prediction in circumstances where they cannot be relied on to behave in the same way as their parent systems, and it includes exploratory investigations that are essentially inductive (Baconian experimentation) The other style of modelling (above the curve) is modelling designed always to err on the side of safety It tests models more frequently than is really necessary, it uses them for prediction less frequently than would be possible, and it includes exploratory investigations that are strictly deductive (Kantian experimentation) The first style of modelling is - 65 - Analogue and numerical forward modelling of sedimentary systems; from understanding to prediction Utrecht, 9 – 11 October 2003 prevalent whenever models are made that have unconstrained auxiliary hypotheses and large numbers of free parameters; such modelling says very little of value about the system concerned, because models such as these do little more than obey the modeller who made them The second style of modelling is effectively possible only for models that are close to being logically identical to their parent systems - these are models that talk back 7) An example will be given of each of the two styles of modelling, both to illustrate the essential differences between them and to point out their strengths and weaknesses A model of landscape development in southeastern Australia provides the example of ‘academic play’, and a model of sedimentary cyclicity provides the example of a model that talks back Figure 1 The testing-prediction relationship curve separates the two styles of scientific modelling - 66 - Analogue and numerical forward modelling of sedimentary systems; from understanding to prediction Utrecht, 9 – 11 October 2003 Modelling the impacts of climate change on erosion, sediment production, and landscape evolution Tucker, G School of Geography & the Environment, Oxford University, Mansfield Road, OX1 3TB, Oxford, United Kindom, gtucker@nimbus.geog.ox.ac.uk Sediment supply is one of the primary controls on deposition rate and stratal architecture In this talk I review analytical and numerical models of landscape denudation, sediment production, and coupled subaerial erosion-deposition systems The present state of the art consists of a variety of different models Most of these represent fluvial and hillslope processes, though some attempts have been made to capture glacial dynamics as well All drainage basin evolution models are able to reproduce branching drainage networks and ridge-valley topography, but these models make different (and generally testable) predictions about transient responses to tectonic, climatic, or eustatic change Efforts at testing alternative models are ongoing and involve a range of approaches, including tests based on case studies with known initial and boundary conditions and known forcing Several lessons have been learned recently about the sediment-flux responses to external (climatic, eustatic, and tectonic) forcing Models predict, for example, that when the forcing timescale is comparable to the geomorphic response timescale, the nature of sediment-flux curves differs fundamentally between scenarios of tectonic versus climatic forcing – the former producing a delayed but sustained response, the latter producing an immediate but transient response These response timescales, and their sensitivity to factors such as source terrain size, can be derived from analytical or numerical models, but their predictions are mostly untested In terms of climate forcing, recent work has unpacked the overly simplistic ‘wet versus dry’ thinking of the past and begun to reveal how particular aspects of climate change can influence denudation rates and sediment supply For example, theoretical work implies that short-term climate variability can have a dramatic impact on sediment production, which supports the hypothesis that climate change is responsible for worldwide accelerated sedimentation in the late Cenozoic Although the mechanisms leading to geomorphic sensitivity vary, nonlinearity and sensitivity to highfrequency climate change seem to be general properties of many different geomorphic systems - 67 - Analogue and numerical forward modelling of sedimentary systems; from understanding to prediction Utrecht, 9 – 11 October 2003 Scaled models of syntectonic sedimentation – review of principles and first results Urai, J.L & Kukla, P.A RWTH Aachen University Sedimentary systems which are active under conditions of active tectonics show a range of different types of non linear responses which are incompletely understood Scaled models are useful tools to understand the interactions in both sedimentary and tectonic systems However, experiments which might combine these two have not been attempted yet In this paper we review the basics of designing scaled model experiments of both tectonic and sedimentary systems, and discuss the limitations of current techniques Some of the limitations of current experiments have been resolved by a new sandbox now in operation at Aachen University which operates submerged in water This way, models containing water-saturated layers of sand and clay can be deformed Recent developments in image analysis technology allow real-time high resolution analysis of the displacement field at length scales less than a grain’s diameter, and resolution of an unprecedented level of detail in the organization of deformation patterns This system is suitable for experiments where a simple sedimentary system is simulated during movement on an active fault We present first results of such experiments and discuss the scope for larger scale and more complex simulations involving growth faults - 68 - Analogue and numerical forward modelling of sedimentary systems; from understanding to prediction Utrecht, 9 – 11 October 2003 Outcrop and seismic constraints for 3D numerical stratigraphic forward modeling Van Buchem, F., Granjeon, D & Eschard, R Institut Français du Pétrole, Rueil-malmaison, France Stratigraphic forward modeling allows to quantify the interaction between the three main “processes” that control sedimentation: accommodation (tectonism, eustasy and compaction), sediment supply (clastic supply and carbonate production) and sediment transport A key problem, however, is to determine the relative contribution and influence of each one of these parameters The only way to address this problem is to work with the best documented and understood case studies available In addition, the insight gained from them, feeds the memory of the model, and can be used as constraints in less well documented studies In this presentation we will give two examples of carbonate systems, one mixed carbonate/siliciclastic system, and two siliciclastic systems In most of the examples high resolution sequence stratigraphy has been applied to unravel the fine scale architecture of these systems - - - - The first carbonate example is the Natih Formation of Cenomanian age (Upper Cretaceous) that outcrops in northern Oman (van Buchem et al., 2002) Our work demonstrated that in this formation twice an organic-rich intrashelf basin was formed mainly controlled by the response of the sedimentary system to the rate of sea level rise Tectonism only played a minor role in the initiation of the intrashelf basins The stratigraphic modeling effectively produced these basins, based on differential sedimentation rates of the carbonates in response to the sea level fluctuations The second carbonate example is from the Upper Miocene in Mallorca The work by Pomar (2001) showed that a change in ecosystem caused a change from a low angle ramp to a rimmed platform Using the ecological parameters of this study in the stratigraphic modeling (depth of carbonate production, type of producers), allowed to reproduce this transition in stratigraphic organisation In the Lower Miocene of south central Turkey a mixed carbonate siliciclastic system has been studied in seismic scale outcrops (Bassant, 1999) Here the interplay between carbonates and siliciclastics was the main challenge, with siliciclastics inhibiting carbonate sedimentation during highstand and fall of sea level (around the point source), while during sea level rise an ecological ‘window’ was created for carbonate sedimentation Introducing a sensitivity to siliciclastic input for the carbonate producers permitted to model this complex interfingering pattern The Eocene of offshore Brasil has been studied using wells and high resolution 3D seismic (Pinheiro-Moreira, 2000) This database allowed to determine the 3D organisation of the turbidite system Stratigraphic - 69 - Analogue and numerical forward modelling of sedimentary systems; from understanding to prediction Utrecht, 9 – 11 October 2003 modeling led to a validation of the seismic analysis in this deep offshore environment, and to a better understanding of the timing, geometry and facies of turbidites in two different basin margin settings (ramp and shelfbreak; Granjeon et al., 2001) - The last example concerns the Colorado basin in Argentina This basin was initiated during an early Mesozoic rifting period, followed by a Cretaceous to Miocene sag period, to ultimately reach the present day passive margin configuration Only the upper third (Upper Cretaceous to Quaternary) of the sedimentary column is covered by wells, located at the margins of the basin A stratigraphic simulation was constraint by excellent seismic data and these few wells, to quantify the geological parameters and evaluate the facies distribution in the nondrilled areas (Mancilla et al., 2002) Basin modeling was then used to asses the hydrocarbon potential of this basin (Haring et al., 2002) Though stratigraphic modeling is in many ways a powerful tool to test the coherency and imagination of the geologist, the ultimate test of the modeling results is the comparison with the hard field and subsurface data The case is made here that the real advances in stratigraphic modeling will come from top quality geological studies, allowing to quantify the parameters of dynamic sedimentological models in a high resolution time framework Acknowledgements: Dionisos is a 3D stratigraphic forward model, developed by IFP and a consortium of companies including Total, Shell, Repsol-YPF, Chevron-Texaco, Petrobras, Agip, IMP, and Pemex - 70 - Analogue and numerical forward modelling of sedimentary systems; from understanding to prediction Utrecht, 9 – 11 October 2003 Impact of discharge and sediment flux on Basin Margin Architecture: An experimental approach Van den Berg van Saparoea, A.P., Postma, G & Dalman, R Universiteit Utrecht, Faculteit Aardwetenschappen, Budapestlaan 4, 3584 CD, Utrecht, The Netherlands, apvdbvs@geo.uu.nl In most cases it is very difficult to evaluate the stratigraphic record in terms of formational processes Important parameters in fluvial-deltaic settings are relative sea-level and the ratio of discharge (Q) and solid load (Qs) We use analog modeling for unraveling the role of each of these formational processes The changes in the modeled system are monitored by means of digital elevation maps (DEM's) of the surface, and are calibrated against the last glacial cycle stratigraphic record of the Colorado (Texas, USA) fluvial-deltaic system The influence of relative sea-level at constant Q/Q s ratio has been investigated in a previous series of experiments (Van Heijst et al 2001, Basin Research) In the experiments described here Q/Q s ratio is varied, while the rate of change in relative sea-level is kept constant Our preliminary results indicate that the efficiency of sediment transport increases with higher Q/Qs ratios A system with high Q/Qs ratio is predominantly progradational, while a system with a low Q/Q s ratio shows progradation and aggradation over the entire shelf Furthermore, a high Q/Qs ratio leads to increased headward erosion rates in the fluvial valleys incised in the shelf Therefore, connection of the shelf valleys with the trunk river occurs earlier than in case of a lower Q/Q s ratio, which means that even though the system is fluvial dominated (i.e strongly progradational), the influence of sea-level fluctuation on the fluvial domain is strong A sudden increase in discharge (and thus increase in Q/Qs ratio), as is postulated to have occurred in the Colorado system, results in the model in instantaneous adjustment (lowering) of the equilibrium slope in the fluvial valley, and increased sediment yield at the river valley mouth The climate shift also causes increased avulsion frequency and aggradation over almost the entire shelf If the pulse coincides with the late sea-level fall (past the fall inflection point), it will delay the onset and magnitude of headward erosion on the shelf and so decreases the influence of sea-level on the river system A shift in climate can apparently have a strong influence on the development of the system, modifying importantly the impact of glacio-eustatic sea-level changes on the system In conclusion: - High Q/Qs ratios produce strongly progradational systems, high knickpoint migration rates in the valleys and relatively early connections of shelf and fluvial valleys; - 71 - Analogue and numerical forward modelling of sedimentary systems; from understanding to prediction Utrecht, 9 – 11 October 2003 - Low Q/Qs ratios produce predominantly aggradational systems, low knickpoint migration rates and relative late connections of shelf and fluvial valleys; - Climate shift towards wetter conditions causes a strong sediment pulse at the river mouth, increases avulsion activity and so enhances wide distribution of sediment over the shelf - 72 - Analogue and numerical forward modelling of sedimentary systems; from understanding to prediction Utrecht, 9 – 11 October 2003 High resolution 3D Forward Stratigraphic modelling of Cretaceous carbonate platform systems VAN DER ZWAN, C.J.1, MASSE, J.-P.2, BORGOMANO, J.1, 2, LAMMERS, H.1 & FENERCI-MASSE, M.2 1) SIEP-SEPTAR, P.O.Box 60, 2280 AB, Rijswijk, The Netherlands, Kees.vanderZwan@shell.com 2) University of the Provence, Labo Sedimentologie, 3, place Victor Hugo, 13331, Marseille, France, jborgo@up.uni-mrs.fr 3D Forward stratigraphic modeling is applied in the petroleum industry to predict the presence and quality of reservoirs, source rocks and seals both on exploration and production scales These models consist of 3dimensional representations of facies attributes that can be related to physical properties of reservoirs, seals and source rocks The forward modeled facies and geobodies can also be used to constrain production scale reservoir architectures The main input parameters to the 3D stratigraphic modeling in any depositional settings are: (1) tectonic subsidence, (2) initial bathymetry, (3) eustatic sealevel and (4) sediment supply In a clastic setting, the latter parameter reflects the amount of sediment entering the system In a carbonate setting this reflects in situ production and re-distribution of carbonate material The first three parameters can be obtained or reconstructed from standard seismic and deterministic geological interpretation or are directly availa ble from regional sources The fourth parameters, carbonate production is the subject of ongoing research, is dependent of many other ecological and environmental parameters and requires sensitivity analysis Recent high-resolution outcrop studies of Lower Cretaceous systems in Southern France improved our understanding of the development of Cretaceous carbonate platforms This data set has shown the interrelationships between water depth, energy levels and the various facies associations in a 'Rudist' platform setting These data have been used to calibrate the 3D forward stratigraphic modelling of similar Cretaceous carbonate platform systems in the subsurface at the scale of producing oil fields The software package DIONISOS accurately modelled the stratigraphy and facies distribution of a Cretaceous carbonate platform in the Cassis and Mont Puget outcrops near Marseille (SE France) and in a Cretaceous producing field In Cassis and Mont Puget, inner and outer platform settings were modelled, respectively, whereas in the Cretaceous Field various scenarios were used to test the sensitivity of the controlling parameters Evaluation of the resulting models shows that the most important parameter in stratigraphic forward modelling of such carbonate platforms is changes in "accommodation space" This parameter determines the space available to be filled by carbonate growth The - 73 - Analogue and numerical forward modelling of sedimentary systems; from understanding to prediction Utrecht, 9 – 11 October 2003 changes in carbonate growth potential have less impact, provided carbonate growth is sufficient to fill the space created Forward models have been built for inner and outer platform settings both in outcrops and in producing fields Independent calibration of these forward models indicates that they compare closely, with a vertical resolution of one meter, with stratigraphic architecture of outcrops and fields The ability of stratigraphic forward modelling to build such accurate and highly detailed models demonstrates that stratigraphic forward modelling is a valuable new technique not only to improve our understanding of the subsurface, but also for the prediction of reservoir architecture both on an exploration and production scale - 74 - Analogue and numerical forward modelling of sedimentary systems; from understanding to prediction Utrecht, 9 – 11 October 2003 Combination of Structural Balancing, Reverse Basin and Forward Stratigraphic Modelling: Southern Cantabrian Basin (NW-Spain) Vesolovsky, Z Geologisch-Paläontologisches Institut, University of Heidelberg, Im Neuenheimer Feld 234, D-69120, Heidelberg, Germany, zbynek.veselovsky@urz.uni-hd.de The processed transect (24km) situated at the southern margin of the Cantabrian Mountains (NW-Spain) comprises the whole basin infill between top of basement (560Ma) and time of maximal burial (34Ma) This part of the Variscan orogen is represented by a foreland thrust and fold belt, further shortened during Alpidic orogenesis, offering magnificent outcrops in each individual thrust sheet In order to carry out basin modelling at this tectonically affected region, a multidisciplinary approach of detailed field mapping, structural balancing and stratigraphic modelling is required Total tectonical shortening of the basin, derived from 2D structural balancing of the deformed basin infill, amounted to 54% at minimum 2D reverse basin modelling investigated the quantitative development of the basin architecture and long-term evolution of accommodation space in time Stratigraphic forward modelling quantified sedimentary processes (erosion and sedimentation rates), refined the sequence stratigraphic model, and offered geometrical minimum/maximum models of the sedimentary patterns Three major subsidence trends obtained from 2D reverse basin modelling reflect different plate-tectonic development stages of the basin Precambrian to Ordovician times recorded uniform tectonic subsidence rates (-11 to 19 m/Ma) Differential subsidence triggered by local tectonics (-28 to 66m/Ma) generates marked changes of depositional environments (Silurian until Late Devonian) Our study indicates major influence of total subsidence and sediment supply liable for the remarkable alternating siliciclastic and carbonate deposits during the Devonian Eustatic sea-level fluctuations were only of subordinate importance In the Upper Carboniferous, eastward migrating depocentres coupled with high rates of tectonic subsidence (-177 to 300 m/Ma) reflect movements of the Variscan front - 75 - Analogue and numerical forward modelling of sedimentary systems; from understanding to prediction Utrecht, 9 – 11 October 2003 Non-unique sequence stratigraphic architectures Waltham, D., Udofia, M & Nichols, G Department of Geology, Royal Holloway University of London, Egham, Surrey TW20 0EX, UK, d.waltham@gl.rhul.ac.uk Sequence stratigraphic architectures are controlled by subsidence, eustatic sealevel and sediment supply A key problem, both for real-world architectures and for computer models, is that there may be more than one combination of these controls which produces the same geometry In this paper we investigate the general conditions under which this nonuniqueness occurs and we illustrate this using computer generated crosssections which, indeed, show identical architectures resulting from differing control-functions The simplest case is that of a non-erosive model with a constant coarse/fine ratio in the input sediment Such models produce identical results for all runs which have the same sealevel versus sediment supply curve More general cases with time-varying coarse/fine ratios and timevarying tectonics can be handled by requiring these curves to also be fixed when plotted against sediment supply All of the preceding examples are special cases of models in which the incremental change in stratigraphy is controlled by the amount of accommodation space but not by its rate of creation or destruction This requirement is violated if an erosion rate is introduced to the model Surprisingly, however, multiple near-identical geometries can still be produced for erosive models provided the sealevel curves are suitably adjusted Finally, the methodology derived from the above conclusions is applied to a 2D seismic line from the Baltimore Canyon - 76 - Analogue and numerical forward modelling of sedimentary systems; from understanding to prediction Utrecht, 9 – 11 October 2003 Insights into Carbonate Platform Drowning Mechanisms using Stratigraphic Forward Modeling Warrlich, G & Burgess, P.M Shell International Exploration and Production B.V., P.O.Box 60, 2280 AB Rijswijk, The Netherlands Mechanisms of carbonate platform drowning remain poorly understood, since modern production rates imply that even the most rapid rates of relative sea-level rise are insufficient to outpace production Other proposed drowning mechanisms include water temperature changes, changing nutrient levels, plate movement into higher latitudes, erosion or stripping of sediment from platform tops by transport, and rapid water depth increase during lag periods (deep flooding) We have used two different stratigraphic forward models to investigate the operation of the latter two mechanisms One model concentrates on sediment transport on the platform top, and the other that uses cellular automata to control carbonate productivity and hence simulates a lag process Model runs combine long term subsidence with a 100 ky eustatic signal and typical shallow water carbonate production rate to determine under what combination of these parameters drowning occurs - 77 - Analogue and numerical forward modelling of sedimentary systems; from understanding to prediction Utrecht, 9 – 11 October 2003 Modelling Source Rock Distribution and Quality Variations: The New OF-Mod 3D Technology Zweigel, J SINTEF Petroleum Research, S.P Andersens veg 15b, 7465 Trondheim, Norway, Janine.zweigel@iku.sintef.no In exploration the ability to predict hydrocarbon occurrence and quality variations within a prospect - prior to drilling - is of large importance Particularly, recently developed 3D modeling techniques are gaining significance with respect to volumetric hydrocarbon predictions The source rock is the basis of every petroleum system and the first prerequisite for a hydrocarbon accumulation to occur But source rock distribution, type and quality variations are still among the least constrained parameters during basin modeling studies The OF-Mod program is a process-based modeling tool, which mimics the development and the variation of source rock facies Consequently, it allows quantitative prediction of source rock potential away from well control and results in a significantly improved input for kinetics, expulsion and migration studies The concept was designed in early 98 and in meantime the 2D version of the software has been applied in many national and international studies and has gathered scientific approval The further development of the software into a 3D version is a consequence of the technological evolution during the last years and will lead to a significantly improved picture of the complex interaction of processes effecting source rock deposition In a theoretical example we will illustrate the possibilities, differences and consequences of 2D and 3D source rock models with respect to quantitative estimates Additionally, we will show the capabilities of the new 3D tool with special attention to integrated, high-resolution basin modeling studies and, in contrast, application in exploration frontier areas, where only little information is available - 78 - ... -3- Analogue and numerical forward modelling of sedimentary systems; from understanding to prediction Utrecht, – 11 October 2003 INCORPORATION OF NUMERICAL AND PHYSICAL FORWARD MODELLING INTO... the model - 18 - Analogue and numerical forward modelling of sedimentary systems; from understanding to prediction Utrecht, – 11 October 2003 Numerical and analogue modelling of sedimentary basin... our understanding of geological variation in the field - 15 - Analogue and numerical forward modelling of sedimentary systems; from understanding to prediction Utrecht, – 11 October 2003 Modelling