ABSTRACT Lake Hulun, the fifth‐largest lake in China, is a shallow lake (water depth <10 m) with typical wave‐dominated landforms developed around the shoreline, with a semi‐enclosed bay located in its southern corner. This novel study aims to understand wind‐driven hydrodynamics and its related depositional patterns in the data‐sparse Lake Hulun. To achieve this, a series of numerical simulations were conducted with a hydrodynamic and sediment transport model. The simulated hydrodynamic patterns are greatly influenced by wind direction shifts but are subject to little impact from wind speed changes which act mainly to accelerate flow. By varying the location and depth of the deepest part of the lake, this study reveals that the location of the depth centre has little impact on the overall hydrodynamic pattern of wind‐driven waterbodies. When the wind direction is perpendicular to the long‐axis shore, currents around the short‐axis shore flow in a direction that follows the wind direction. This study considers the wind‐induced longshore currents that are oblique to the long‐axis shore as the main driving force in transporting sediments along the shore and erosion of the shoreline. The formation of semi‐closed bays in both Lake Hulun, together with its nearby sister lake – Lake Buir – are attributed to the north‐west prevailing wind direction. Further exploratory simulations confirmed that prevailing winds tend to induce parallel distributed submerged sediment accumulations in the nearshore zone, challenging the notion of sediment accumulation solely in deep water zones. This study provides valuable insights into the hydro‐sedimentary dynamics in wind‐driven waterbodies, offering a process‐based perspective and contributing to current understanding of the palaeogeography of ancient lake systems.

While adapting to future sea-level rise (SLR) and its hazards and impacts is a multidisciplinary challenge, the interaction of scientists across different research fields, and with practitioners, is limited. To stimulate collaboration and develop a common research agenda, a workshop held in June 2024 gathered 22 scientists and policymakers working in the Netherlands. Participants discussed the interacting uncertainties across three different research fields: sea-level projections, hazards and impacts, and adaptation. Here, we present our view on the most important uncertainties within each field and the feasibility of managing and reducing those uncertainties. We find that enhanced collaboration is urgently needed to prioritize uncertainty reductions, manage expectations and increase the relevance of science to adaptation planning. Furthermore, we argue that in the coming decades, significant uncertainties will remain or newly arise in each research field and that rapidly accelerating SLR will remain a possibility. Therefore, we recommend investigating the extent to which early warning systems can help policymakers as a tool to make timely decisions under remaining uncertainties, in both the Netherlands and other coastal areas. Crucially, this will require viewing SLR, its hazards and impacts, and adaptation as a whole.

Capillary pinning refers to the immobilization of CO2 at capillary barriers when the uprising CO2 pressure is lower than the capillary entry pressure of the overlaying pore throats. Also known as local capillary trapping, it has been proposed as a fifth geologic CO2 storage mechanism, alongside structural, solubility, residual, and mineral trapping. Despite extensive research, the fragmented terminology surrounding capillary pinning has led to confusion, making it challenging to synthesize findings effectively. Often conflated with mechanisms such as residual and hysteresis trapping, capillary pinning is commonly underestimated or completely overlooked in reservoir-scale models. Furthermore, difficulties in characterizing and upscaling small-scale geologic heterogeneities that influence capillary pinning contribute to significant uncertainties, with estimates of CO2 trapped via this mechanism ranging from 3 % to 100 % of total CO2 trapped via capillary actions. This review explores the fundamental mechanisms, experimental findings, and modeling approaches for assessing CO2 capillary pinning in carbon capture and storage (CCS). It seeks to bridge the gap between the reservoir engineering community, with its extensive expertise in hydrocarbon recovery but that needs adjustments for CCS applications, and the subsurface storage community, which stands to benefit from this knowledge but often lacks access to relevant literature. Additionally, the study identifies key research opportunities to advance the understanding of capillary pinning in sedimentary rocks, ultimately enhancing the efficacy and reliability of CCS operations.

Alluvial stratigraphy builds up over geologic time under the complex interplay of external climatic and tectonic forces and internal stochastic processes. This complexity makes it challenging to attribute alluvial stratigraphic changes to specific factors. Geological records indicate pronounced and persistent climatic changes during the Phanerozoic, while the effects of these changes on alluvial stratigraphy remain insufficiently documented. We provide evidence for 405 k.y. long-eccentricity climate forcing of alluvial stratigraphy in the lower Eocene Willwood Formation of the Bighorn Basin, Wyoming (USA). Two ∼90-m-thick intervals, characterized by a relative paucity of sand, dominance of sinuous-river channels, and floodplain sediments with better-developed paleosols, coincide with eccentricity maxima as determined through integrated stratigraphic methods. These intervals are interspersed with three contrasting intervals, marked by relatively high sand content, prevalent braided-river channels, and less-developed paleosols, corresponding to eccentricity minima. A comprehensive genetic model that integrates climate, source-to-sink system, and alluvial dynamics to explain these findings remains to be elucidated. Given the consistent presence of the 405 k.y. eccentricity cycle throughout Earth’s history, it is plausible to infer that its influence may be discernible across a wide array of alluvial stratigraphic records.

AbstractSyn‐sedimentary compaction or consolidation is an important process in deltaic environments because it affects both the local morphodynamics and hydrodynamics as well as the delta‐scale accommodation space. However, the impact of syn‐depositional compaction on the sediment distribution and the interdependency between different delta areas related to the sediment budget are not fully understood. This paper simulates syn‐depositional compaction using improved 1D grain‐size compaction formulations, integrated into hydrodynamic and morphodynamic modelling software Delft3D. The updated code is used to model sedimentation in mud‐rich deltas under various compaction rate scenarios, which represents the maximum compaction rate potential of sediment that experiences the highest overburden stress in the delta. The simulated deltas are analysed by first classifying their plan‐view area development into depositional elements: distributary channel, underfilled channel, delta plain, mouth bar, delta front and pro delta depositional elements. Then, sedimentation by mass, accommodation space and depositional segment metrics are calculated using the interpreted depositional elements. The results for zero compaction rate scenarios (0 mm year−1) show that limited space‐varying and temporal‐varying accommodation is available to deposit sediment in the delta plain depositional element. Therefore, the sedimentation mainly occurs in the mouth bar depositional element. For low‐mid compaction rate scenarios (0.01–1 mm year−1), the additional syn‐depositional accommodation space in the delta plain depositional element increases sedimentation in this area, limiting sedimentation in the mouth bar depositional element. For high compaction rate scenarios (>1 mm year−1), a further increase in the accommodation space in the delta plain depositional element leads to lateral sedimentation attributed to channel relocation, where the sedimentation mainly occurs in the mouth bar depositional element. This study shows that, although considered a gradual process, syn‐sedimentary compaction does impact long‐term delta evolution by influencing the distribution of sedimentation in the delta.

AbstractRiver sediment supply (Qs) and longshore sediment transport (LST) are recognized as two paramount controls on river delta morphodynamics and stratigraphy. We employed the Delft3D model to simulate the evolution of deltas from fluvial to wave‐dominated conditions, revealing the interplay between river‐ and wave‐driven sediment quantities. Wave‐influenced deltas may show alternating accumulation and retreat patterns driven by avulsions and wave‐induced sediment diffusion, posing coastal management challenges. Deltas with higher wave energy evolve under a fine balance between river supply and intense wave‐mediated sediment redistribution and are highly vulnerable under conditions of sediment reduction. Reducing Qs by ∼40%–70%, common in modern dammed rivers, can rapidly shift bypass from ∼0 to 1 (no bypass to complete bypass). This leads to accelerated diffusion and potential sediment loss in modern deltas. The study highlights the importance of accurately computing sediment quantities in real‐world deltas for improved management, especially under increasing anthropogenic and climatic pressures.

Two rectangular-shaped lakes, Lake Hulun and Lake Buir, located at the boundary between China and Mongolia, only c. 75 km apart and therefore experiencing similar wind fields, have been studied based on satellite images and field surveys in order to compare their geomorphological and sedimentological characteristics. The wind-driven hydrodynamics, which have a significant effect on the development of littoral landforms and on sediment distribution, have been discussed for the two similar lakes that experienced a prevailing wind perpendicular to their long axis. A conceptual model related to wind-driven water bodies and sediment distribution is proposed. Wave-influenced to wave-dominated deltas, beaches, spits, and eolian dune deposits develop around these two lakes, with a strikingly similar distribution pattern. These features locally inform the longshore drift and help reconstruct the water circulation induced by wind forcing. Under the NW prevailing wind regime, the spits developed on the SW coast with a NW-SE extension, which was influenced by the NW-SE longshore currents. The same influence was observed in the delta extension in the NE area. The differences lie in the presence of fan deltas in the NW region of Lake Hulun, but not in Lake Buir. Additionally, the width of the beach and eolian deposits on the downwind coast of Lake Hulun is three times greater than that of Lake Buir which were caused by the differences in sediment supply and wind fetch between the two lakes. Lake Hulun and Lake Buir provide two reliable examples to understand the relationship among the wind field, provenance, hydrodynamics, landforms, and asymmetrical distribution of clastics in elongated lakes. They also represent relevant modern analogs, which may also be of guiding significance to wind-driven sand body prediction in lacustrine basins.

Summary This poster outlines a hierarchical, multiscale modelling approach that is adapted from proven hydrocarbon reservoir characterization workflows to determine which 3D sedimentological and stratigraphic heterogeneity types at which temporal and spatial scales and in which configurations are most important for successful long-term CO2 storage. The approach is particularly in saline aquifers that are data-poor but have the potential to store large CO2 volumes. It uses the Representative Element Volume (REV) concept and associated upscaling methodology to characterise sedimentological heterogeneity types, and it leverages novel modelling tools that facilitate rapid model construction and prototyping, geometrically accurate representation of key geological heterogeneities in models, and computationally efficient simulation of all CO2 trapping mechanisms over relevant spatial and temporal scales.

Sedimentation on river floodplains is a complex process that involves overbank flooding, crevasse splaying, and river avulsion. The resulting floodplain stratigraphy often exhibits floodplain aggradation cycles with alternating fine-grained overbank flooding deposits that underwent significant petrogenesis, and coarser-grained, avulsion-belt deposits largely devoid of pedogenic impact. These cycles are linked to lateral migration and avulsion of channels driven by internal dynamics, external factors, or a combination of both. To better understand the spatial and vertical variability of such floodplain aggradation cycles, we map these in three dimensions using a photogrammetric model of the lower Eocene Willwood Formation in the northern Bighorn Basin, Wyoming, USA. This allows identifying 44 floodplain aggradation cycles in ∼300 m of strata with an average thickness of 6.8 m and a standard deviation of 2.0 m. All the cycles are traceable over the entire model, pointing to their spatial consistency over the 10 km2 study area. At the same time, rapid lateral thickness changes of the floodplain aggradation cycles occur with changes up to 4 m over a lateral distance of 400 m. Variogram analyses of both field and numerical-model results reveal stronger consistency of floodplain aggradation cycle thicknesses along the paleoflow direction compared to perpendicular to paleoflow. Strong compensational stacking occurs at the vertical scale of 2−3 floodplain aggradation cycles (14−20 m), while full compensational stacking occurs at larger scales of more than six floodplain aggradation cycles (>41 m). The lateral and vertical thickness variability of the floodplain aggradation cycles, as well as their compensational stacking behavior, are interpreted to be dominantly driven by autogenic processes such as crevasse splaying and avulsing that preferentially fill topographic lows. External climate forcing may have interacted with these autogenic processes, producing the laterally persistent and vertically repetitive floodplain aggradation cycles. The spatial variability of floodplain aggradation cycles demonstrated in this study highlights again the need for three-dimensional data collection in alluvial floodplain settings rather than depending on one-dimensional records.

A complete annual cycle of the dynamics of fine-grained sediment supplied by the Omo and smaller rivers is simulated for Lake Turkana, one of the world’s large lakes, with the hydrodynamic, wave and sediment transport model Delft3D. The model is forced with river liquid and solid discharge and wind data in order to simulate cohesive sediment transport and resuspension. It simulates stratification due to salinity, wave generation and dissipation, and sediment advection and resuspension by waves and currents, with multiple cohesive sediment fractions. A comparison of the simulation results with remotely-sensed imagery and with available in-situ sediment deposition rates validates the model. By devising simulation scenarios in which certain processes were switched on or off, we investigated the contribution of waves, wind-induced surface and bottom currents, salinity-induced stratification and river jet, in resuspending and transporting fine sediments in the lake basin. With only the wind or river influence, most of the sediment deposition occurs in the first 10 km off the Omo River mouth and at a depth < 10 m. When waves are switched on, increased bed shear stresses resuspend most of the fine sediments, that are then deposited further and deeper in the first 30 km, in water depths > 30 m. This study sheds new light on sediment transport in Lake Turkana and in great lakes in general, favouring the view that wind-waves can be the main agent that transports sediment away from river mouths and to deeper areas, as opposed to river-plume or gravity-driven transport.

Crevasse splays generate subtle local relief and contribute to fluvial basin sedimentary filling but controls on splay development along dryland rivers remain poorly understood owing to limited field, laboratory, and nu-merical modelling studies. Based on previously-acquired field data and new remote sensing observations of splay morphology and sedimentology (e.g. slope, width, length, grain size) and flooding characteristics (e.g. discharge, water depth and extent) near the terminus of the non-vegetated, ephemeral Rio Colorado on the southeastern margin of Salar de Uyuni, Bolivia, we undertake process-based modelling using Delft3D to isolate the role of hydrological controls on crevasse splay morphodynamics. Holding the potential sediment supply constant, we focus on the role of discharge (outflow from trunk channel to crevasse channel during rising stage), floodplain water levels, and backflow (reflux to the trunk channel during falling stage). Using nine different model runs, each with 10 simulated flood cycles, we show that the processes associated with these hydrological controls result in various outcomes, from short crevasse splay channels that may bifurcate and develop depositional bars to longer splays with one primary channel that mainly transfers sediment across the floodplain. Results reveal that increases in flood discharge lead to more rapid splay sedimentation and stabilization of a single crevasse channel. Increases in floodplain water level lead to shorter but wider splays and facilitate the formation of multiple stable crevasse channels. High floodplain water levels probably restrict splay length owing to decel-eration of outflow as floodplain water is encountered, but separate crevasse channels may form downstream as backflow breaches the trunk channel levee during falling stage. These findings support and extend previous observations from the Rio Colorado and other dryland rivers worldwide. Future modelling studies that consider a wider range of hydrological, sedimentological, and floodplain topographic conditions will help develop more comprehensive numerical models of splay development. A combination of insights from field, laboratory experimentation, remote sensing and modelling will improve knowledge of the cascades of channel-floodplain dynamics that characterise many dryland endorheic basins.

Summary Many stratigraphic features occur at a scale that is at the edge or below vertical seismic resolution. Thus, they cannot be directly observed in the seismic data, while still having an important effect on the fluid flow within the system. The better understanding of these sub-seismic scale features or heterogeneities can help decrease subsurface uncertainty. Here we present a novel method that integrates forward stratigraphic modelling, petrophysics, and geophysics to decipher the seismic imprint of heterogeneities in wave-dominated, shallow marine environments. The proposed three-stepped method starts with defining geology-related input parameters for BarSim, a stratigraphic forward modelling software that produces models that include stratigraphic architecture, grain size distribution, and facies distribution. Then, the geological data is translated, cell by cell, into petrophysical data (density, Vp, and Vs) using emphirical relationships. Finally, the forward seismic modelling is performed by combining a finite difference approach strategy and angle-dependent full wavefield migration to retrieve the angle gathers This method also allows the generation of large amounts of field-independent data suitable for machine learning applications.

Abstract In natural deltaic settings, mixed hydrodynamic forcings and sediment properties are known to influence the preserved delta deposits. One process that has not received much attention yet is syn‐sedimentary compaction of clastic sediment on millennial‐scale delta evolution. To study how compaction interacts with delta morphodynamics and preserved sediment, a modelling approach is proposed. A 1D grain‐size dependent compaction model was implemented into Delft3D‐FLOW, which provides an opportunity to understand the underexplored connection between grain sizes supplied to the deltas and sediment compaction. The compaction model allows deposited sediment to decrease in volume due to the accumulation of newly deposited sediments above or the elapsed time. Differences in morphological trends are presented for scenarios defined by the composition of sediment supply (mud rich and sand rich) and the maximum allowed compaction rate in the model (0–10 mm year−1). The resultant deposits are classified into sub‐environments: delta top, delta front and pro delta. The delta top geometry (e.g. area increase, rugosity and aspect ratio), sediment distribution alongshore and across sub‐environments, and delta top accommodation (e.g. volume reduction and average water depth) are compared. The modelling results show that compaction of the underlying delta front and pro delta deposits increases the average water depth at the delta top, driving morphological variability observed in the mud‐rich and sand‐rich deltas. The morphological changes are more prominent in the mud‐rich deltas, which experience larger compaction‐induced volume reduction for the same scenario. Moreover, higher compaction rates further increase the delta top accommodation, resulting in more deposition and evenly distributed sediment at the delta top. This leads to a less significant area increase and a wider delta top with a smoother coastline. The presented modelling results bridge the knowledge gap on the influence of syn‐sedimentary compaction on long‐term delta morphodynamics and preserved sediment. These findings can be applied to unravel the controlling processes in ancient delta deposits and predict the evolution of modern systems under changing climates.

The lower Eocene Willwood Formation of the Bighorn Basin, Wyoming, USA, is an alluvial succession with a sand content varying around 25%. It has been studied intensively for palaeontology, palaeoenvironments and palaeoclimates, as well as sedimentological and stratigraphic analysis. Channel dynamics were studied at a relatively low resolution throughout the basin over the geological time from late Palaeocene to early Eocene. Here, a high-resolution study is reported to complement previous research at the basin scale. Efforts are made to document the characteristics and river planform styles of most sandstone bodies encountered through ca 300 m of alluvial stratigraphy in a 10 km2 area of the Deer Creek part of the McCullough Peaks area situated in the basin axis of northern Bighorn Basin. Four channel facies associations are recognized and ascribed to four river planform styles: crevasse channel, trunk channel, braided-like channel and sinuous-like channel, with the latter two types dominant. Braided-like and sinuous-like channel sandstone bodies differ significantly in thicknesses, being on average 6.1 m versus 9.0 m, but they have similar palaeoflow–perpendicular widths of on average 231 m and palaeoflow directions of on average N 003°. Braided-like and sinuous-like river planform styles show no spatial dependency in the 10 km2 study area. Results of this study are in line with existing basin-scale depositional models that are composed of a single axial system fed by several transverse systems dominantly from the west. The feeding of these systems could be influenced by palaeoclimate changes possibly controlling their contribution over time, thereby impacting river planform styles. At the same time, changing water discharge hydrograph, sediment load, and overbank cohesiveness may have equally driven the observed river planform style changes within the basin without a major role of catchments.

Depositional models for clastic sedimentation in large lakes, notably in rift lakes, emphasize on downslope river and gravity-driven processes. Wind-driven waterbodies (WWB), a recently-defined category of lakes, display features created by wave related processes and wind-induced water circulation such as beach ridges or spits along the coasts, as well as sediment drifts, sedimentary shelf progradation and erosional surfaces in deeper, offshore domains. A coupled hydrodynamic, wave and sediment transport three-dimensional Delft3D model was established for Lake Turkana, East Africa, one of the world’s greatest lakes in order to test the WWB validity for fine sediments. Using available data, the model is forced for 1.5 years with river liquid and solid discharge, as well as wind data, in order to simulate cohesive sediment transport and resuspension. The model simulates stratification due to salinity, wave generation and dissipation, and sediment advection and resuspension by waves and currents, with multiple cohesive sediment fractions. Model results were compared with remote sensed imagery and with available in-situ sediment deposition rates, reproducing the general surface suspended sediment patterns, and agreeing with the mass deposition rates data from the literature. By creating scenarios in which certain processes were switched off, the contribution of waves resuspension, wind-induced currents, salinity-induced stratification, and river jet, in resuspending and transporting sediment along the lake could be investigated. With just the wind and/or the river influence, most of the sediment deposition occurs in the first 10 km from the river mouth and at depths from 0 to 10 m. When waves are switched on, significant quantities of sediments can be resuspended by waves, and most of the sediments are deposited in the first 30 km from the river mouth, at depths from 10 to 30 m. This study provides insights on sediment transport in the Lake Turkana, and similarly in great lakes in general, supporting waves as the main agent transporting fine sediments away from river mouths into deeper areas, as opposed to river-plume derived transport.

13 Interaction of allogenic and autogenic forcing in building alluvial stratigraphy remains a complex 14 subject that is critical for paleoenvironmental and paleoclimate reconstruction and subsurface rock 15 property prediction. Astronomical forcing of alluvial stratigraphy is poorly documented so far as this 16 driver strongly interacts with autogenic and other allogenic processes making it difficult to trace 17 astronomical climate changes in these laterally highly variable sediments. In the lower Eocene Willwood 18 Formation, Bighorn Basin, Wyoming, USA, a lot of evidence has been gathered to relate dominant 19 floodplain aggradation cycles to precession-scale climate change. One floodplain aggradation cycle 20 consists of two phases: (1) a longer overbank phase with relative channel stability and strong paleosol 21

The Golo River drains a steep catchment (average gradient of 30 m km(-1), surface of 1214 km(2)) in the northeast part of Corsica Island, delivering sediments to the Ligurian Sea. In this study, we review and revise the geologic map and constrain the extent of the Golo coastal alluvial plain formations and their relative and absolute chronology. To update the surface extent of each formation, we performed a geomorphologic analysis with DEMs and satellite imagery data coupled with an extensive pedogenic and sedimentary field observations database, including a new borehole of 117,4 m depth. Additionally, we performed in-situ cosmogenic Be-10 analysis from a depth-profile in the well-preserved alluvial terrace Fy2, yielding a minimum age of 70 ka for its emplacement. Our new chronology, based on cosmogenic Be-10 and soil chronosequences, implies older ages than those previously obtained with luminescence methods. Soil mixing by bioturbation is proposed as a possibility to explain differences between luminescence and Be-10 ages. In this scenario, Be-10 dates the original deposition of the alluvial terrace, while luminescence dates a later soil development. We highlighted at least five outcropping alluvial terraces in the Golo coastal plain, which are controlled by sea-level fluctuations and were most likely deposited during past sea-level highstands (close to present-day sea-level). Moreover, we identified from a borehole more than 117 m of coarse fluvial sediments in the plain, that do not outcrop at the surface. New cosmogenic Al-26/Be-10 burial ages suggest that this sedimentary unit results from a thick accumulation of fluvial material filling a zone significantly affected by subsidence, probably accommodated by a normal fault during the Early Quaternary.

Continental passive margins and their hinterlands in the Atlantic realm have been the locus of many Low Temperature Thermochronology (LTT) and time‐Temperature (t‐T) modelling studies that evidence pre‐, syn‐ and post‐rift episodic km‐scale exhumation and burial episodes. In this study, we integrate data from over 30 published LTT and t‐T modelling studies from Morocco and its surroundings using a three‐step workflow to obtain: (a) exhumation/burial rates, (b) erosion rates and (c) palaeoreconstructions of source‐to‐sink domains, between the Permian and the Present. Our synthesis of available t‐T modelling results predicts high exhumation rates in the Anti‐Atlas (0.1 km/Myr) during the Early to Middle Jurassic, and in the High Atlas (0.1 km/Myr) and Rif (up to 0.5 km/Myr) during the Neogene. These rates are comparable to values typical of rift flank, domal or structural uplifts settings. During the other investigated periods, exhumation rates in the Meseta, High‐Atlas, Anti‐Atlas and Reguibat shield are around 0.04 ± 0.02 km/Myr. Interpolation of the exhumation rates at the regional scale allow calculation of the volume of rocks eroded. Estimates of erosion rates are between 0.2 x 10 3 and 7.5 x 10 3 km 3 (in the Meseta and the Reguibat Shield respectively). Ten erosional (quantitative, from interpolation results) and depositional (qualitative, from data synthesis) “source‐and‐sink” maps have been constructed, with emphasis on the Jurassic and Cretaceous periods. The maps integrate the extent of exhumed domains, using information from geological maps, lithofacies and biostratigraphic data from new geological fieldwork and well data from onshore and offshore basins. The results illustrate changes in the source‐to‐sink systems and allow for a better understanding of the Central Atlantic margin hinterlands evolution.

Formation of alluvial stratigraphy is controlled by autogenic processes that mix their imprints with allogenic forcing. In some alluvial successions, sedimentary cycles have been linked to astronomically-driven, cyclic climate changes. However, it remains challenging to define how such cyclic allogenic forcing leads to sedimentary cycles when it continuously occurs in concert with autogenic forcing. Accordingly, we evaluate the impact of cyclic and non-cyclic upstream forcing on alluvial stratigraphy through a process-based alluvial architecture model, the Karssenberg and Bridge (2008) model (KB08). The KB08 model depicts diffusion-based sediment transport, erosion and deposition within a network of channel belts and associated floodplains, with river avulsion dependent on lateral floodplain gradient, flood magnitude and frequency, and stochastic components. We find cyclic alluvial stratigraphic patterns to occur when there is cyclicity in the ratio of sediment supply over water discharge (Q(s)/Q(w) ratio), in the precondition that the allogenic forcing has sufficiently large amplitudes and long, but not very long, wavelengths, depending on inherent properties of the modelled basin (e.g. basin subsidence, size, and slope). Each alluvial stratigraphic cycle consists of two phases: an aggradation phase characterized by rapid sedimentation due to frequent channel shifting and a non-deposition phase characterized by channel belt stability and, depending on Q(s)/Q(w) amplitudes, incision. Larger Q(s)/Q(w) ratio amplitudes contribute to weaker downstream signal shredding by stochastic components in the model. Floodplain topographic differences are found to be compensated by autogenic dynamics at certain compensational timescales in fully autogenic runs, while the presence of allogenic forcing clearly impacts the compensational stacking patterns.

This paper reconstructs the sedimentation volumes and patterns, suspended sediment yields, wind‐induced circulation patterns and sediment trapping efficiency of Lake Strynevatnet, western Norway as an integrated source to sink system. The lake became deglaciated ca 11 ky cal bp, with glacio‐isostatic uplift isolating the basin from the nearby fjord (Nordfjord) ca 9.2 ky cal bp. Based on geophysical data collected in 2010, the upper 15–20 m of Holocene sediment accumulation in the lake was mapped. A sediment body in the centre of the lake indicates a depositional mechanism dominated by suspension sedimentation. The source of this sediment is associated with the adjacent glaciated catchments westward of the lake. Three seismic units were identified based on seismic facies generating an evolutionary model utilizing three depositional units (U1, U2 and U3), in which unit U2 represents the Storegga tsunami event. Unit U3 is further divided into three subunits; U3a, U3b and U3c based on their spatial continuity and subtle downlapping and onlapping relationships. The degree to which wind conditions could have affected the lake depositional patterns were studied utilizing an open‐source coupled hydrodynamic and sediment transport model. The results show that fluvial discharge alone is incapable of generating a circulation pattern in the lake currents. Suspended sediment concentrations in the lake are highest for strong winds. Modelled sediment accumulation on the lake floor shows that mild or absent winds lead to a proximal to distal sediment thickness trend, while strong winds result in uniform sediment thickness. Based on this it is argued that the thickness trends of seismic subunits U3a‐c are related to a variable palaeowind climate. As such, seismic data of lake infills, in combination with numerical modelling, may provide valuable palaeoclimatic information on wind patterns.