The vector based, freeform shoreline development model ShorelineS can efficiently simulate the development of a shoreline through the use of relatively simple bulk longshore transport formulas. This allows it to be multiple orders of magnitude more efficient compared to complex two-dimensional horizontal process-based models. The model does make some assumptions in order to be this efficient. One of these assumptions is the constant profile angle along the shoreline. This means the model does not account for bathymetry. The version of the ShorelineS model used is from 03/08/2023.

This study analyses the applicability of ShorelineS for simulation of a shoreline with a river mouth. To this extent a synthetic case of a shoreline with a river mouth is set up to analyse the model behaviour of ShorelineS in a simplified environment. The effect of many input parameters on the shoreline development is analysed. These parameters include wave parameters, channel parameters, transport parameters, model parameters, and relative sea level rise. The applicability is further tested in a more complex environment with a real-world case. For this, a hindcast is set up. The location of the hindcast is the shoreline of the Rhône delta. This is a wave dominated, sandy coast with a negligible tidal range. Data on the shoreline, the wave climate, the sediment budget, and the shoreline profile were required to get a successful hindcast.

The implementation of a river mouth in ShorelineS is done through specifying the river flow path as well as to what extent the channel should be kept. The sediment discharge is then approximated by a nourishment in the flow path that is pushed out to the shore. This approach was found to work well in a simplified environment through analysis of results from the synthetic case. The different simulations resulted in the expected model behaviour and the simulations were stable.

The results of the hindcast are mostly positive. The hindcast gets a good skill score and the simulations are mostly stable. The biggest differences between the simulated shoreline and the actual shoreline of the Rhône delta can be explained by the existence of relict sediment lobes along the shoreline. These lobes are the result of the combination of progradation and avulsion in the Rhône delta. They make the shoreline profile variable and provide time limited sediment sources.

ShorelineS cannot account for these naturally occurring lobes because of the assumption of the constant profile angle along the shoreline. Combining this with the fact that ShorelineS is incapable of simulating processes related to river dynamics such as avulsion and the forming of mouth bars limits the applicability of ShorelineS in environments governed by natural processes, such as the Rhône delta.

However, there is enough applicability for ShorelineS outside of these environments. When the shoreline is not governed by natural processes but is instead regulated by humans, a canal for instance, the results of the ShorelineS simulations will only get better. The big difference in time and cost efficiency compared to other models makes ShorelineS uniquely suited for applicability where the demand for accuracy of the simulation is lower. For instance, in data limited environments or on a global scale. ... Read more

Deltas are dynamic landforms that develop through the interaction of sediment supply, hydrodynamics, and accommodation. They support large human populations and important ecosystems, yet many deltas are increasingly threatened by subsidence and sea-level rise. One of the key processes contributing to subsidence is sediment compaction. Compaction is an inherent process in delta systems. However, the impact of syn-depositional compaction during active delta formation over millennial timescales remains poorly constrained. This dissertation investigates how syn-depositional compaction influences delta morphodynamics, sediment distribution, and levee breaching, using a process-based numerical modelling approach. These questions are addressed in Chapters 2, 3, and 4 of this dissertation.

To address the above-mentioned questions, we apply and progressively refine compaction formulations within the Delft3D 4 - FLOW code. This approach focuses on mechanical compaction because it contributes to the largest sediment volume reduction compared to biological and chemical compaction. Additionally, it mainly operates within the active part of the delta top. This type of compaction occurs in two phases, primary and secondary compaction, driven by overburden weight and simulated time. Both phases lead to pore fluid expulsion, resulting in sediment volume reduction and lowering of the bed surface (subsidence). By switching compaction on and off in model simulations, the effects of syn-depositional compaction on delta development are assessed. Quantitative metrics are developed to enable comparison between simulations, including changes in delta geometry, sediment mass distribution, accommodation generation, and sediment erodibility.

Modelling results show that syn-depositional compaction generates additional accommodation during delta development, which alters delta morphology. Morphological changes are more prominent in mud-rich deltas than in sand-rich deltas, which experience larger compaction-induced volume reduction for the same compaction rate scenario. In higher compaction rate scenarios, accommodation increases at the delta top, leading to more sedimentation and more evenly distributed sediment at the delta top. This results in a less significant area increase and a wider delta top with a smoother coastline. These morphological responses emerge from feedback between compaction-induced additional accommodation, sedimentation, and channel dynamics.

Additional accommodation generated by syn-depositional compaction also affects the distribution of sediment mass across delta depositional areas. Modelling results show that increased accommodation on the delta plain promotes sedimentation in this area, thereby reducing sediment delivery to the mouth bar and beyond. Further increases in accommodation lead to enhanced lateral sediment redistribution associated with channel relocation, with sedimentation mainly occurring in the mouth bar. Changes in sedimentation within a depositional area are accompanied by compensating changes elsewhere, indicating interdependencies within the delta-wide sediment budget influenced by syn-depositional compaction. These results demonstrate that compaction-induced accommodation redistributes sediment beyond the immediate subsidence area, affecting sedimentation across the entire delta system.

In addition to generating additional accommodation, syn-depositional compaction increases sediment resistance to resuspension. Levees act as key sediment conduits in delta systems, and the location and timing of levee breaching are commonly assessed using proxies that describe the influence of topography on hydraulic forcing acting on levee deposits. However, the role of sediment properties, particularly levee resistance to resuspension, remains poorly constrained. The modelling results show that commonly used proxies, such as superelevation and gradient advantage, are relevant in predicting when and where levee breaching is initiated, but they are insufficient to describe breach progression, which depends on the balance between flow-induced shear stress and sediment resistance to resuspension. Syn-depositional compaction modifies both bed elevation and sediment erodibility, thereby influencing whether breaches are sustained or abandoned.

Overall, this dissertation demonstrates that syn-depositional compaction is a fundamental process influencing simulated delta evolution over millennial timescales. While numerical models cannot capture all processes operating in natural deltas, they provide a controlled framework to explore process interactions that are difficult to observe directly in the field. The results show that syn-depositional compaction affects delta morphology, sediment distribution, and levee breaching, and therefore represents a critical mechanism that should be included in process-based delta modelling studies. ... Read more

Accurate subsurface characterization is critical for emerging energy-transition projects, yet conventional seismic data often fail to resolve metre-scale heterogeneities that strongly influence reservoir behaviour. This thesis develops an integrated workflow that combines stratigraphic forward modelling with seismic forward modelling to improve the detection of sub-seismic stratigraphic features in wave-dominated shoreface systems. Outcrop analysis shows significant variability in petrophysical and acoustic properties, revealing the limitations of lithology-based seismic approaches. By converting grain-size distributions from stratigraphic simulations into acoustic properties, the workflow produces synthetic seismic data that better represent fine-scale stratigraphy. Angle-dependent seismic analysis shows potential for identifying subtle acoustic variations, though current modelling techniques require refinement. The results demonstrate that linking geological, petrophysical, and geophysical data enhances subsurface resolution and point toward future developments involving more complex models, in-well seismic methods, and machine learning. ... Read more

An MDP project performed in the scope of the Delta Futures Lab in collaboration with the Dragon Institute. The report delves into the enviromental threats the Mekong Delta is facing and provides a design framework to deal with these problems. Furthermore, a case study is chosen to display how the framework can be adopted in a practical setting, envisioning what a future looks like where the Mekong Delta co-exists with water. ... Read more

CO2 emissions are a major driver of global warming, contributing significantly to the level of climate change. One promising solution to mitigate this issue is Carbon Capture and Storage, which involves capturing CO2 emissions from industrial sources and securely storing them in reservoirs or aquifers. The study investigates the impact of large-scale reservoir heterogeneity on the efficiency of the CO2 storage by using reservoir models inspired by the Sobrarbe Deltaic Complex outcrop in Ainsa, Spain. Utilizing Google Earth, RRM (Rapid Reservoir Modeling), and CMG software, different reservoir realizations were created, incorporating various levels of petrophysical properties and impermeable layers within the reservoir. The models simulated 100 years of CO2 injection and monitoring. Results indicate that the Base Model, characterized by continuous impermeable layers and high porosity and permeability values, represented the highest cumulative trapped CO2, capturing approximately 3 billion kg of CO2. Models with patchy impermeable layers and lower petrophysical properties values represented lower CO2 trapping efficiency. The results highlight the critical role of reservoir heterogeneity in determining the storage potential and pressure stability of CO2 storage projects, offering valuable insight into the feasibility of carbon storage initiatives. ... Read more

Since early history, humans have been attracted to coastal areas. This can be related to the economic benefits of these areas due to access of ocean navigation, coastal fisheries, tourism and recreation (Seas and Plans, 2011). Around 40% of the world’s population lives within 100 km of the coast (Seas and Plans, 2011). People are drawn to sandy beaches in particular because of its aesthetics and value for specific economic amenities (Luijendijk et al., 2018). Nevertheless, as these beaches are dynamic both in time and space, proper coastal management is required to prevent loss of land and secure future coastal life.

Up till now, studies into coastal erosion have been conducted locally, resulting in site specific observations. However, the promising results of using satellite imagery in the field of coastal engineering allowed studies to be performed at larger spatial scales. This can lead to the identification of areas with similar characteristics, resulting in methodological standardization of approaching a specific problem. A first step toward this new approach of studying shoreline evolution was taken by Luijendijk et al. (2018) who presented a global dataset of annual shoreline positions for sandy beaches over the period 1984-2016 using satellite derived shorelines
(SDS). However, the drivers (causes) of shoreline evolution on a global scale were still unknown, making it only suitable for identifying areas of structural shoreline change, but less suitable for deriving coastal management solutions. Therefore, the research objective in this study is to identify and characterize drivers of shoreline evolution on a global scale using SDS.

This study focused on dynamic sandy beaches, or hotspots, extracted using a method developed by Kras (2019). In this method, using a 2.5-kilometer moving window, transects showing structural shoreline changes and similar characteristics both in space and time were grouped. The small size of the moving window led to locally created hotspots, 95% of which had a spatial extent of less than 10 kilometers, allowing to study shoreline drivers with small to moderate spatial scales (∼10 kilometer). Therefore, the main focus in this study lies on seasonality as a natural driver of shoreline evolution and three anthropogenic drivers: reclamations, nourishments and littoral drift barriers. As seasonality shows inter-annual variability, the temporal resolution of the SDS is increased from annual to monthly.
Using time series decomposition methods, different parameters are extracted that can be used to link the drivers to the SDS. Besides temporal parameters, also parameters related to spatial characteristics are considered. These parameters can be split into identification parameters, used for identifying a driver, and informative parameters, providing knowledge on the behavior of the driver. These parameters were developed and tested using local case studies. Results from these local case studies showed that the identification parameters showed similar behavior along the case studies. This implies that the identification parameters correctly reflect a driver’s behavior. Next, identification of the drivers was verified on a larger scale, all transects within hotspots on West-European coastlines. Verification was done on hundreds of samples using literature or manual inspection of satellite images. Using precision scores, the fraction of true positives to the total identified cases, optimal settings were derived for identification of the drivers. These settings resulted in a pattern of driver identification and characterization along the West-European coastline that is supported by literature.

With the optimal settings for identification determined, the methods were deployed on a global scale. The global dataset consisted out of 3033 prograding and 2121 retreating hotspots containing over 58 thousand transects in total. For these hotspots, SDS were generated over the period 1984-2021 with a monthly temporal resolution. This resulted in a global dataset of more than 26 million monthly shoreline positions. Two other processes, in addition to a seasonal change in wave height, were found to be able to generate seasonal variations in coastline positions from this global dataset. At the Red Sea, even though the wave climate is low in energy (Langodan et al., 2017), the coast is characterized by seasonal behavior. However, in this basin, seasonal variations in water levels rather than the wave climate best described this pattern. In addition to varying wave height and water level, seasonal beach morphology can also be caused by a shift in wave direction. This was observed in southern and western parts of Australia. Furthermore, non-seasonal beaches were primarily seen in low-energetic wave regions where neither of these other two processes occurred, as is the case in the Mediterranean. In regions where seasonal shoreline fluctuations are caused by differences in wave energy, minimum shoreline positions were found at the start of the summer. However, the period in which minimal shoreline positions are observed may be observed at a different time of the year in regions where seasonal shoreline behavior is driven by water level variations or a shift in wave direction. The identification of reclamations pointed out that this driver was especially linked to shoreline evolution in the Middle East and East-Asia. Furthermore, while the amount of constructions of reclamations remained
constant on a global level over the period 1987-2017, in these two areas an increase was observed. Opposite behavior was found by the identification of nourishments, as this driver was identified more often in the period 2007-2017 compared to the two decades before that. Moreover, nourishments were mostly observed in Western countries, for example the USA and the Netherlands. Nevertheless, also in Non-Western countries, an increment over time in the amount of nourishments could be detected. This indicates that throughout the entire world the use of nourishments as a measure to prevent coastal erosion is increasing. Shoreline evolution linked to littoral drift barriers was mostly observed in North-America, Europe and Africa. Downdrift (erosive) hotspots were mostly observed in Africa while in North-America and Europe mostly updrift (accreting) hotspots were linked to littoral drift barriers. On a global level, a combination of an updrift and downdrift hotspots (a pair) was observed in only 2% of all hotspots.

The outcomes above can support local-scale studies by identifying the drivers of shoreline evolution, describing their characteristics and even create standardization by analyzing areas with similar behavior. Hence, it can be concluded that spatiotemporal parameters describing the behavior of a driver can be used to identify and characterize drivers on a global scale using SDS. Nevertheless, not all drivers of shoreline evolution were included in this study. Therefore, to include drivers with larger spatial scales, hotspots should be extracted by using a larger moving spatial window. Furthermore, by increasing the spatiotemporal resolution on which this extraction is based, accuracy of the spatial extent of the hotspots is expected to increase. The small proportion of pairs identified for littoral drift barriers can be partly explained by the erroneous spatial extent of some hotspots. Finally, drivers are identified independently from each other neglecting their interactions. Even though interactions might be complex, drivers should not be identified independently as this will rather
require local studies than support them. Still, even though refinement and further development of the methods is required, this research has shown that identifying the drivers of shoreline development on a global scale using SDS has great potential for sustainable coastal management in the face of future challenges
... Read more

Over the last years the Netherlands has often had to deal with droughts and water shortages during summer. This problem is caused by long periods without rain but with high evaporation rates and is enhanced by groundwater extraction for drinking water. Due to climate change, these droughts are expected to occur more often and become more severe. A possible strategy to mitigate drought in the eastern part of the Netherlands is to scale down the groundwater extraction, thereby limiting the groundwater depletion. In this case however, an alternative drinking water source has to be created. This research explores the option to use the former river bed of the Rhine near the Dutch-German border, the Rijnstrangen, to create this alternative drinking water source, answering the following question: How can retention of Rhine water in the Rijnstrangen contribute to drought mitigation in the eastern part of the Netherlands?

With this study, it is shown that the Rijnstrangen realistically can contribute up to 100 Mm3/y to the drinking water production in its region. This is up to 75% of the drinking water production of the Dutch province Gelderland, in which the Rijnstrangen is located. The exact maximum extraction volume from the Rijnstrangen depends on policy choices such as the maximum accepted water level in the Rijnstrangen and the maximum accepted average extraction from the region around the Rijnstrangen.

From a water quantity point of view, the maximum extraction volume of up to 100 Mm3/y indicates that utilizing the Rijnstrangen as a retention reservoir is a promising option to contribute to drought mitigation in the eastern part of the Netherlands. Therefore, further investigation of this idea is relevant.
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To produce accurate 3D fluvial architecture models, it is important to understand the influence of internally generated autogenic controls versus externally generated allogenic controls. When studying a fluvial system, autogenic controls such as river meandering and avulsions generally dominate over 103-104 years. Allogenic controls such as climate change and tectonics dominate more at time scales of 105-106 years. A dominant control is astronomical climate change that may produce cyclical fluvial sedimentary successions. The resulting alluvial architecture of autogenic and of allogenic forcing is highly different and it is expected to largely influence geothermal flow through fluvial reservoirs. The aim of this research is to depict the impact of allogenic (cyclical) versus autogenic (non-cyclical) fluvial sedimentation on geothermal flow. Process-imitating and stochastic based modelling software Flumy is used to generate fluvial facies models where either hypothetical cyclical forcing or hypothetical non-cyclical forcing was the dominant force. These models are subsequently tested for geothermal flow using DARTS (Delft Advanced Terra Simulator). We find that the Flumy numerical model can be used to produce hypothetical cyclical and hypothetical non-cyclical alluvial architecture. The main difference between the architectures is the shape of the sand bodies. The cyclical model has overall thicker, laterally wider sand bodies. The non-cyclical model has thinner, less wide, but more often connecting sand bodies. Geothermal flow modelling shows that matching N/G in the cyclical and non-cyclical model in the 20-40 % N/G range gives similar pressures at a constant, fixed water rate. This points to the hypothesis that, at comparable N/G, the well connectivity must also be similar. The non-cyclical model breakthrough times in the 20-30 % N/G range are generally equal or slower, compared to the cyclical model. This gives credence to the hypothesis that the cyclical model has overall equal or slower flow paths between the well connections in the geothermal doublet. The difference in flow path hypothesis can be properly tested through visualizing 3D streamlines and is a recommendation for the future. ... Read more

Turbidity currents transport land-derived sediment to deep sea where theirdeposits form large geological structures termed submarine fans. Giventheir large areal extent and high sand content, submarine-fan deposits formsignificant hydrocarbon reservoirs. Their internal architecture is often poorlyresolved. With much of the three-dimensional architecture of the turbiditelobes below seismic resolution, there is commonly a significant level of un-certainty associated with respect to the reservoir geometry and quality.At the end of submarine channels, turbidity currents lose confinementand encounter a slope break, in response, the current decelerates and forms a deposit, a turbidite. Repeated passage of turbidity currents forms a stackof deposits that are generically termed lobes.Subsequent flow events modify the bathymetry by erosion and deposi-tion, thereby affecting the trajectory of subsequent flow events. Due to self-formed relief, beds start stacking laterally, in 'compensation'. A complex but ordered stratigraphy is created by repeated cycles of shifts in deposition, which results in variability in deposits that governs reservoir connectivity. In this study, multiple consecutive turbidity currents flowing over self-formed relief are modeled using a process-based numerical model (Delft3D-FLOW). The response of successive turbidity currents and their deposits to variations in channel slope was tested. Models with steeper channel slope were observed to result in more vigorous flows with deposits that cover a larger surface area. Following passages of turbidity currents were observed to erode bed sediment in the channel and thereby diminish the amount ofreadily erodible bed sediment for following turbidity currents. With the current model set-up, the deposit relief was insufficient to observe lateral stacking of deposits. These simulations provide insight into the depositional processes and the controls on the geometry and sedimentary trends of the deposits emplaced by successive turbidity currents flowing over a slope break and losing confinement.
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The thesis explores the socio-territorial orientation of Finnmark, northern Norway, in relation to the growing international interest for the development of the mineral industry. This interest is met locally with directly opposing views, favouring on the one hand the cultural development related to land-based practices, and on the other hand exploiting Finnmarks high resource potential for the benefit of municipal growth and job development. Difficulties arise with the geographic distribution of ethnicities. Proposed developments of the mineral industry find more support in coastal areas and although most indigenous Sámi find their home inland, they depend to a large degree for their livelihood on this coastal areas. The current fractured political landscape is highly related to and tied up with the complex history of internal center-periphery dynamics, colonization and stigmatization, which took (and in a way are still taking) place under the flagship of national assimilation policies of ‘norwegianization’, sustaining Finnmarks not-so-postcolonial present. In this perspective, three mining cases are of interest, due to the different social and political responses to the mining plans: Nussir in Kvalsund, Bidjovagge in Kautokeino and Sydvaranger in Sør-Varanger. Motivations behind decision-making on these cases illustrate clearly the conflicts of interests and demonstrate the difficulties for coexistence of directly opposing world views. Through an understanding of the formation of societal strata, the argument of the thesis unfolds over an in-depth spatiotemporal and on-site analysis of the cases and their specific socio-territorial setting in Finnmark. I argue that we should look more critically at the tendentious role of the modus operandi of urbanists and geologists (more specifically of resource mappers), in their way of influencing decision-making and framing and shaping cultural life, especially in contested territories. The thesis then moves towards a possible way forward through redesigning our conventional tools and methods for a more inclusive territorial-based endogenous growth model, such an inclusive growth model has the potential to bring together on the long term the opposing visions and ideas on the future of the mining industry and the preservation of indigenous culture. I end by arguing that knowledge building from a combined perspective has the potential to evolve the acceptance amongst cultures abiding by different worldviews. Effectively, the newly proposed geological era of the Anthropocene, proposes also the updating modern science with cultural diversity, asking for renewed responses away from the modern tradition. ... Read more

Accelerated sea level rise (SLR) is predicted to have multiple adverse impacts on the coastal zone, aggravating phenomena such as coastal erosion on sandy coasts. For climate change adaptation planning and informing policy, morphodynamic changes occurring at coastlines are becoming increasingly important. In this study, a calibrated Delft3D model forced by real-time wave conditions, was applied to simulate and assess the morphological behaviour of the Delfland coast in response to accelerated SLR over a 30-year time period. The calibrated Delft3D model uses a novel acceleration technique called brute-force merged (BFM) proposed by Luijendijk et al. (2019), which enables the modelling of multi-decadal predictions, with significant gain in computational effort. An assumption of the study was that no nourishments take place, i.e. no additional sediment supply. The Sand Engine (Zand Motor in Dutch), currently located along this coast was also excluded from the model, thereby assuming a straight unnourished coastline. A selection of six SLR scenarios was simulated, including a no SLR scenario used as the reference case. The chosen scenarios covered the full bandwidth of accelerated SLR projections translated for the Dutch coast up to 2100, assuming increased mass loss from the Antarctic ice sheet, a hypothesis proposed by DeConto and Pollard (2016). These projections therefore exceed those presented in the IPCC AR5. Based on the recent literature, the SLR rates selected, ranging from 3 mm/year to 120 mm/year, are assumed plausible and useful for the modelling study. Model outputs that are assessed include erosion and sedimentation plots, and volume changes, particularly erosion volumes. Analysis shows that no major change to the general coastal system behaviour occurs due to accelerated SLR; erosive sections in the south remain erosive and accretive regions in the northern part remain accretive. This is influenced mainly by gradients in alongshore sediment transport and presence of structures. Erosion volumes increase with higher SLR rates, indicating an increase in erosion rate due to accelerated SLR. Volume changes were calculated in different alongshore sections and in different depth/elevation zones in the cross-shore direction in order to identify regions more vulnerable to accelerated SLR. It is determined that the southern section is most impacted by SLR causing increased erosion, particularly in the subtidal zone. Processes driving the observations and trends are discussed in the study. With significant SLR, dune erosion also occurs due to water levels and waves being able to reach higher elevations. The dunes along the Delfland coast are the primary sea defence which protects the hinterland from flooding, therefore it is critical to consider potential dune erosion due to accelerated SLR. Implications of the model study’s findings are briefly discussed, in the context of coastal maintenance policy and implementation of nourishments. Evaluating the added value of Delft3D as a coastal impact model is another objective of the study. Delft3D shows a number of benefits, including detailed analysis at multiple spatio-temporal scales. Another is the inclusion of transport processes in both alongshore and cross-shore directions, which is not the case for the Bruun Rule or 1-D coastline models. A limitation of Delft3D is that it does not include aeolian transport processes, and so dune growth cannot be simulated. ... Read more

Fluvial reservoirs are difficult to model due to the high permeability contrast between the sandstone bodies and the overbank deposits and the complex geometry of the permeable (sandstone bodies) and impermeable zones (overbank deposits). A set of fluvial meandering models has been generated using FLUMY. The models represent a range of Net-to-Gross ratios and sandstone body geometries. In order to quantify the effect of sample size on effective properties, the models are evaluated based on the statistical moments of the probability distributions of porosity and single-phase permeability as a function of sample size. The porosity and permeability show a high spread at small sample volumes, but the spread reduces as the sample size increases. A normalized standard deviation, the coefficient of variation, has been used as a criterion for the variability of the probability distributions. The coefficient of variation of the porosity and the horizontal permeability show a monotonic decline as a function of sample size. The coefficient of variation of the vertical permeability does not show a monotonic decline. This is caused by a drastic decrease of the mean of the vertical permeability with increasing sample volume. The mean of the horizontal permeability also decreases with increasing sample size, but to a lesser extent. The mean of the probability distributions of permeability as a function of sample size converges much earlier than the standard deviation. This convergence indicates that we can determine the effective properties at the Representative Elementary Volume (REV), without reaching REV. The convergence of the mean could potentially be used as a criterion for the relevant spatial scale of upscaling from the fine scale static model to the coarse scale model. Furthermore, if cells are uncorrelated at a scale where the mean of the permeability is not a function of sample volume anymore, random attribution of properties can be used to populate dynamic grid cells. ... Read more

The coastline of the United States has been threatened by significant erosion for the past decades. A study in 2000 predicted that 25% of the houses located within 150 meters of the shoreline will be destroyed by erosion in 2060. The east coast of the US experiences an average erosion rate of roughly one meter per year. Moreover, the Atlantic coast can be classified as highly erosive as it is vulnerable to hurricanes in the summer as well as winter storm events. The erosive behavior is counteracted by the application of beach and shoreface (nearshore berm) nourishments, referred to as non-feeder nourishments.
To illustrate this problem on a local scale, a project side in the northeast of Florida is selected, Duval County. At this site numerous beach and shoreface nourishments have been applied with an average nourishment cycle of approximately 5 years. However, taking the effect of climate change and sea-level rise into account, the required nourishment volumes will increase in the future. This means that other solutions need to be investigated. In the Netherlands, the pilot experiment Sand Engine is carried out, involving a large-scale feeder nourishment. It is expected that this type of nourishment will be more beneficial as it reduces the nourishment frequency and contains a concentrated displacement area. The nourishment will spread along the adjacent coastlines in a natural fashion, reducing the impact on ecology. Lastly, large-scale nourishment can temporary lead to additional recreational and environmental area, with a potential of creating new ecological habitats. This leads to the following research question:
'How can a large-scale feeder nourishment be beneficial for highly erosive coastlines along the Atlantic coast of the US, and how can the effects of such nourishments be quantified on different timescales?'
In order to evaluate the effect of large-scale feeder nourishments on the coast of Duval County, an evaluation framework has been developed. This framework is based on ecosystem services, which describe the way humans are linked to and depend on nature. Three main ecosystem services have been identified, which have been divided into several sub-services indicated by quantifiable parameters. The first ecosystem service is coastal protection, which is evaluated in terms of flood protection and maintenance of the coastline position. The time-dependent indicators for these sub-services are the foreshore volume and the distance between the Coastal Construction Control Line and the Momentary Coast Line. Secondly, recreation is evaluated by the sub-services of beach leisure, swimming, kitesurfing and strolling. Beach leisure is indicated by the dry beach width, swimming by the offshore directed flow velocities around the nourishment, kitesurfing by the additional sheltered area, and strolling by the walkable beach length along the shoreline. Lastly, the ecosystem service of habitat provision is split into three sub-services, namely nursery area, turtle nesting and dune growth potential. The nursery area is quantified by mapping the existing ecotopes, turtle nesting is evaluated by the beach slope and the beach width and finally the dune growth potential is indicated by the intertidal beach width.
The researched nourishment alternatives differ from geometric shape and in nourishment frequency. Two shapes are connected to the beach and have a width to height ratio of (1:1) and (1:3), while one is detached from the beach in the form of an island. The first two shapes have been applied with a frequency of 1, 3, 5 and 10 years, and the island only for 5 and 10 years. The morphological development of the alternatives is predicted with the numerical model of Delft3D over a period of 10 years.
All nourishment alternatives have been evaluated for all the selected indicators. For coastal protection the most suitable nourishment alternative is an attached and elongated nourishment with a frequency of 10 years (the (1:3) nourishment alternative). For recreation it differs largely per sub-service, but considering all sub-services have an equal weighting, the (1:3) alternative in combination with a 1 year frequency and the offshore island alternative with a 10 year frequency perform the best. The (1:3) nourishment alternative with a 1 year frequency creates the most benefit for beach leisure and swimming, while the offshore island with a 10 year frequency does this for kitesurfing and strolling. Finally for the ecosystem service of habitat provision, the offshore island in combination with a 10 year frequency has the most potential. The most suitable nourishment alternative cannot be selected for Duval County as a whole since the weighting between the different ecosystem services is unknown, as it depends on the stakeholders involved.
Based on the analysis of the different nourishment strategies, the following conclusions have been drawn for the application of large-scale feeder nourishments:
•Large-scale nourishments can decrease the required coastline maintenance on the long-term as long as they are placed within the dynamic wave zone. However, shore connected shapes can cause initial downdrift erosion because of their protrusion into the ocean, which requires extra nourishments at these locations. The application involves a trade-off between applying a low nourishment frequency with a large volume, and being able to place all the sediment within the dynamic zone.
•The largest temporal additional recreational and environmental area is created by emerged alternatives. Shore connected nourishments provide the largest accessible beach area, while detached nourishments provide the largest sheltered area. In this study, the increase in sheltered area was up to 5 times as large compared to the original situation.
•Nourishment alternatives that are elongated and streamlined along the coastline have a larger region of influence after the simulation period. Here, the region of influence was 10-20\% larger compared to the other shapes.
•Large-scale feeder nourishments have the potential to transport sediment over the entire project area under sufficient tidal and wave forcing. It leads to a more gradual spread of sediment than small-scale nourishments, as they tend to pile up within the placement area.
•As the disturbance of large-scale feeder nourishments is less frequent and concentrated, the adjacent coastlines are fed in a natural fashion, reducing the stress on ecology.
In conclusion, large-scale feeder nourishment can be evaluated by the approach of ecosystem services. They can certainly be beneficial for highly erosive coastlines, but its optimal dimensions depend on the required wishes for the considered coastline. ... Read more

The Late Cenozoic Eridanos River brought vast amount of sediments to the North Sea Basin accumulating more than 1000m of deltaic deposits in less than 3.5 Ma. Since the gas discoveries in the shallow sediments were made, more attention is being paid to these deltaic deposits and that resulted in more data availability.
This study concentrates on the Eridanos Delta and identifies the properties of the delta in terms of its progadation distance and sedimentation rate and compare different time models to the ones provided by Overeem (2001) and Kuhlmann (2008). Furthermore, studies the reservoir rocks in terms of their petrophysical properties and facies distribution. Moreover investigates the reasoning behind the shallow sediments gas accumulations and factors behind the concentration of all the discoveries around the A and B blocks. Lastly, constructs a 3D model of the reservoirs distribution in the study area and their properties by integrating the study results of geological, geophysical, petrophysical and reservoir engineering data.
Such results were achieved by interpreting a high resolution 3D seismic survey and 2D lines in combination with wells’ wireline logs and core data. Seismically, a total of 12 units were mapped to categories the successions (3.6 – 1.8Ma) that deposited post the Mid Miocene Unconformity. In addition, more than 20 wells were used to understand the reservoir properties in which seven wells have cores. Sedimentological aspects were assessed by studying the descriptions of cores and thin sections and the measurements of the core plugs. Gas accumulations were studied by evaluating the production data for gas and linking the gas to its source.
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A mega-feeder nourishment is a concentrated nourishment that disperses over time due to wind, waves, and tide, and as a result ‘feeds’ its adjacent coasts. During the design phase of a nourishment, performance indicators can enable an objective comparison of a mega-feeder nourishment to alternative nourishment strategies, In the case of an existing mega-feeder nourishment, predictions of the performance enable an objective assessment of the need for additional nourishments in the proximity of a mega-feeder nourishment.
Today, engineers and policy makers rely on expert judgement when assessing alternative nourishment strategies, or the need for additional nourishments. Currently no tool exists that enables quantification of the performance of a mega-feeder nourishment. Existing models that describe and predict developments of nearshore coastal areas have been applied before to assess the developments of a mega-feeder nourishment, but have not been validated specifically to describe the performance in terms of alongshore feeding. The research question is therefore: "How to describe and predict macro-scale mega-feeder nourishment performance with behaviour-based coastal indicators?"
A tool is proposed that enables the quantification of the performance of a mega-feeder nourishment, as well as the validation of models that describe and predict the performance of a mega-feeder nourishment, The tool is specifically aimed at quantifying the performance in terms of the alongshore feeding. The tool comprises of indicators that representatively quantify the contribution of sediment, the region of feeding, and the time it does so.
The tool is applied to the Sand Engine, used as a case study to examine the applicability. This Sand Engine, constructed during the spring of 2011, has a nourishment volume of 21.5Mm3, initially spanned a width of 2.4km and extended 1km into the sea. Application of the indicators to the Sand Engine confirmed the performance developed with continuous trends, suggesting the performance can be predicted.
From the validation of the model approaches, it is concluded that the analytical model can be used to predict the initial performance of a mega-feeder nourishment, if the longshore spreading is derived from the LST equation by Kamphuis. Second, if the bathymetry is regularly monitored (e.g. semi-annually), the input of the analytical model can be calibrated, enabling long-term predictions of the performance. If more detailed descriptions of the developments of a mega-feeder nourishment are needed, a bruteforce process-based numerical modelling approach can serve as a method to describe and predict the feeding performance of a mega-feeder nourishment.
The performance of the Sand Engine is predicted with the validated models up until 2030. The volumetric growth will stagnate on the south, while on the north it is expected to grow up to 4Mm3. The width will increase to approximately 7km. From this, it is concluded that it is unlikely the Sand Engine will meet its original objective of contributing to coastal safety along the Westland coast (17.2km). Further, the half-life of the Sand Engine will be reached near 2030, indicating the actual lifetime is significantly longer than the design lifetime (20 years).
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Process-based method forward stratigraphic modelling provides advantages in reservoir modelling by simulating the geological process mathematically, and the genesis of geologic formations over time (Michael et al., 2010). In spite of its advantages, Miller et al. (2008) have recognised significant challenges in process-based simulation models, one of them is the incapability to condition to subsurface data. The problem in conditioning the data can be addressed by using an alternative method named multiple-point geostatistics (MPS) in modelling the subsurface since its introduction in 1993 by Guardiano and Srivastava. MPS considers the relationship between multiple data points that is different from the conventional geostatistical methods that are commonly limited to using a linear relationship between data (Guardiano and Srivastava, 1993). By using the process-based simulation model as training image (TI) for MPS simulation, MPS should be able to address the conditioning issue in process-based simulation model.

Over the past decade, most research in MPS has emphasized on new algorithms for improving efficiency of MPS (Mariethoz and Caers, 2014; Mariethoz and Lefebvre, 2014), but there are still issues remain for the workflow to be widely used in geosciences. Furthermore, using nonstationary TI such as process-based simulation model in MPS are still an issue because the workflow is always different for specific cases. Until recently, little published works are available in applicating nonstationary TI in MPS.

The principal objective of this project was to determine an optimised methodology that allows the use of nonstationary process-based simulation model for TI input with MPS simulation in the fluvial-dominated delta. The process-based simulation model used in the study is a post-processed data from numerical model done in process-based modelling software Delft3D (Lesser et al., 2004) which is the PhD work of van der Vegt in 2018. There were two different cases utilised in this study that represents the whole delta development: Case A with high repetition in the patterns and Case B with low repetition in the patterns.

In order to achieve the desired outcome, this study links process-based simulation model with MPS using unconditional and conditional 2D MPS simulation with two different approaches: zonation approach and control map approach. The realisations from the unconditional simulation have to be validated until successful unconditional MPS simulation. The conditional MPS simulation were carried out when the unconditional realisations have been acknowledged as the approved results in mimicking the patterns of the Delft3D model. Lastly, the results were evaluated with four methods: connectivity function, E-type models, conditional variance models, and analysis of distance (ANODI).

In all of the MPS simulation results, the use of control map approach with unilateral simulation path proved to deliver better realisations for unconditional and conditional MPS simulations. Also, this study has presented an optimised workflow of 2D MPS simulation on using process-based simulation model in fluvial-dominated delta environment as TI based on different conditions of patterns’ repetition and hard data distribution. ... Read more

Traditional reservoir modelling utilizes a stochastic approach centered around statistics to generate a 3D representation of the reservoir. While the results of a stochastic approach are favorable, they tend to lack the detail that is necessary to fully understand the different aspects of the reservoir, more precisely, the inclusion of heterogeneities. A possible solution to this problem is the use of process-based models. Process-based models utilize the physical processes involved in the transportation, deposition, and erosion of sediments. As a result, the models generated are more complex in nature and better represent what is found within the subsurface. The use of process-based models within reservoir modelling is a a relatively new process that has yet to be fully utilized due to the difficulty in calibrating the models with well data. Before process-based models can be tested on their viability to include the multi-scalar heterogeneities, the model must be calibrated to match the real-world data. To test this, a combination of field work, lab work, and computer simulations is required. In this experiment, the Roda Sandstone Member, a Gilbert-type delta deposit in Northern Spain, was chosen as the unit of focus. The Roda Sandstone consists of multiple prograding sand lobes, with Roda Y being chosen as the focus of this experiment. The Roda Y sandstone exhibits a predominately medium and coarse grain distribution in the central locations of the sand lobe, and a fine and very fine distribution in the distal locations. Five simulations were run within the process-based modelling software "Delft3D", each with varying sediment input parameters, to observe the effects on the results. The results for the simulations show a strong calibration for each of the five simulations for coarse and medium grained sand, with a percent difference between the model results and the field data of 4-8%. The fine and very fine data contain a higher average difference between the two data sets, ranging from 18-23%. The difference for mud averages around 11%, with predominately more mud being deposited within the simulations. The large differences for the fine and very fine grained can be attributed to the difference in the size and shape of the sand lobe produced by the simulations. In locations were the two data points are equivalent in regards to depositional location within the sand lobe, a high correlation is observed. The results indicate that process-based models have the potential to be a very useful took within reservoir modelling. As this is the first step in a series of steps, additional testing is required for the additional aspects involved in utilizing process-based models to better incorporate heterogeneities within reservoir models. ... Read more

Our understanding of the Earth’s interior is limited by the access we have of its  deep layers, while the knowledge we have of Earth’s evolution is restricted to harvested information from the present state of our planet. We therefore use  proxies, physical and numerical models, and observations made on and from the surface of the Earth. The landscape results from a combination of processes  operating at the surface and in the subsurface. Thus, if one knows how to read  the landscape, one may unfold its geological evolution.

In the past decade, numerous studies have documented km-scale upward and downward vertical movements in the continental rifted margins of the Atlantic  Ocean and in their hinterlands.These movements, described as exhumation (upward) and subsidence (downward), have been labelled as “unpredicted” and/or  “unexpected”. ‘Unpredicted’ because conceptual, physical, and numerical models that we dispose of for the evolution of continental margins do not generally account for these relatively recent observations. ‘Unexpected’ because the km-scale vertical movements occurred when our record of the geological history is insufficient to support them. As yet, the mechanisms responsible for the km-scale vertical movements remain enigmatic.

One of the common techniques used by geoscientists to investigate the past kinematics of the continental crust is to couple ‘low-temperature thermochronology’ and ‘time-temperature modelling’. In Morocco alone, over twenty studies were conducted following this approach. The reason behind this abundance of studies and the related enthusiasm of researchers towards Moroccan geology is due to its puzzling landscapes and complex history. In this Thesis, we investigate unconstrained aspects of the km-scale vertical movements that occurred in Morocco and its surroundings (Canary Islands, Algeria, Mali, and Mauritania).  ... Read more

Geological reservoir models, created based on sparse core and seismic data, inform hydrocarbon production, geothermal applications and aquafer management. Important factors contributing to reservoir quality in these applications include the heterogeneities within and connectivity between the relevant geo‐bodies constituting the reservoir. The transport and preservation of sediment at the time of deposition impacts these factors. Therefore, a better understanding of sediment delivery, transport and deposition can be used to better quantify reservoir properties. This same computational methodology can also be applied test hypotheses concerning the depositional processes responsible for preservation of ancient deposits. Constraining such hypotheses improves our understanding of the paleo‐sediment dynamics and the accuracy of future geological models. ... Read more

Growing interest has been expressed the last decades regarding the Late Cenozoic, gas-bearing sediments of Southern North Sea Basin. Comprising the shallow subsurface of the Dutch offshore sector, these sediments have
been deposited by Eridanos fluvio-deltaic system, draining the Fennoscandian and Baltic shield through the present Baltic Sea. Three successful producing fields - A12-FA (2007), F02a-B-Pliocene (2009) and B13-FA (2011)- and
five under development have triggered the conduction of several studies in the offshore area. However the deltaic environment has been characterized as highly complex owing to its influence by the onset of Northern Hemisphere
Glaciation and thus the processes that governed the system have not become entirely understood. Enhanced cooling followed by the waxing and waning of the glaciers during warmer periods had an immediate impact on sediment
supply, accommodation space and mineralogical input. Although the sediments have been studied in terms of chrono-biostratigraphy, no systematic investigation with respect to the three main aforementioned factors as well
as the regional sequence stratigraphy and its link to the reservoir deposits has been made up to date. Therefore, this study employed sequence stratigraphy as a method to examine Eridanos conditions of deposition, investigate the
interplay between accommodation space and sediment supply and explore the nature of the gas-bearing reservoir sediments. The adopted methodology is comprised of two basic pillars, observation and interpretation. The first
records as clearly as possible the observations arise from the sequence analysis while the second extracts the meaningful information and interprets it in terms of temporal and spatial concepts. Using 2D seismic and well log data the basic observations were the stratal terminations, stacking patterns, seismic facies and the shoreline trajectory.
Seismic and well log interpretation showed that the delta experienced multiple events of sea level fall which forced the shoreline to regress basinward and caused sediment erosion or non-deposition. These events are bounded
by nine time-significant surfaces of subaerial unconformities which constitute the depositional sequences. Normal regression comprised the dominant depositional trend, combined with aggrading-prograding patterns, leading to
characteristic alternations of highstand and lowstand system tracts. Three main depositional environments which correspond to open marine turbidites (submarine lobes), delta front and delta top were identified from well logs,
core descriptions and the seismic facies analysis. The study suggests that the shallow gas is located in the alternations of silty-sandstones and claystones of the delta plain which comprise the vertical stacking of parasequence
topsets within the highstand- lowstand system tracts. Reconstruction of the relative sea level changes and sedimentation rates was made based on a technique introduced by this study. It uses the average thickness of each seismic
unit in order to interpolate time between the three known absolute ages obtained by the literature. The graphs showed that the accommodation space was generated by a low rate of sea level rise while sedimentation rates were
increasing over time. However the scarcity of time constrains in combination with the uncertainty in the estimation of seismic volumes resulted in a low resolution outcome. A comparison between the findings of this study and
those of the existing literature was made. The overall depositional trends and conditions seem to be in accordance with the other surveys. Nonetheless the proposed interplay between accommodation and supply can be assigned as
local since the examined area is limited compare to areas studied in literature. Limitations are traced in the quality of the 2D seismic data hampering the observation regarding the relation between the reflectors and the surfaces.
Consequently, the study offers an insight into the conditions under which the gas-bearing deltaic sediments were deposited and tries to place them in the established sequence stratigraphic framework. Also it provides information
regarding the distribution of the deltaic environments and identification of the reservoir rocks within each setting. The resulting interpretation can be used for prediction of the reservoir formations since the genetically-related
packages where they were identified are distributed in a predictable manner within a sedimentary basin. ... Read more