T. F. Baars, Richard Huis in ‘t Veld, Linzhi Zhang, Maaike Koopmans, D. McLean, A. Martinius, H. Abels
Abstract Orbital driven climate control on sedimentation produces regional, stratigraphically repetitive characters and so cyclostratigraphic correlation can improve correlation and identify stratigraphic trends in borehole sections. This concept is commonly used to correlate marine and lacustrine strata. However, in the alluvial domain, its use is more challenging because internal, local dynamics controlling sedimentation may interfere with the expression of cyclic climate forcing. Intervals of low net-to-gross may be important for successful application in this domain as they tend to better document regional changes. This study applies climate-based stratigraphic correlation concepts to improve well correlations, characterise vertical sand distribution, and identify potential reservoir targets in a generally low net-to-gross interval. Coarsening upward sedimentary repetitions (cyclothems) are identified and correlated with high certainty in nineteen well sections in the upper Carboniferous Westoe and Cleaver formations of the Silverpit Basin. Local sedimentary dynamics provide variability in the character of the cyclothems and several types of cyclothem are classified. Correlation of sections using cyclothems recognised on wireline logs is done twice: once manually and once semi-automatically. The semi-automated correlation is based on calculation of deviation curves which depict stratigraphic changes that are less dependent on absolute wireline values and follow vertical trends more clearly. The correlations provide composite stratigraphies that are analysed using vertical proportions curves. Both approaches yield similar results in terms of stratigraphic trends. However, for detailed correlation of wells, the manual correlation is better at accounting for any local variability within the system. The same two zones of higher net-to-gross ratios are found using both correlation methods. These are linked to palaeoclimatic changes driven by long eccentricity and the proposed climate stratigraphic model has predictive value for identifying sandstone occurrence. The climate-based stratigraphic correlation improves the assessment reservoir distribution and properties on small (10–20 m thickness) and large (100–200 m thickness) stratigraphical scales.
{"title":"A cyclostratigraphic framework of the Upper Carboniferous Westoe and Cleaver formations in the southern North Sea Basin as a methodology for stratigraphic reservoir characterisation","authors":"T. F. Baars, Richard Huis in ‘t Veld, Linzhi Zhang, Maaike Koopmans, D. McLean, A. Martinius, H. Abels","doi":"10.1017/njg.2023.8","DOIUrl":"https://doi.org/10.1017/njg.2023.8","url":null,"abstract":"Abstract Orbital driven climate control on sedimentation produces regional, stratigraphically repetitive characters and so cyclostratigraphic correlation can improve correlation and identify stratigraphic trends in borehole sections. This concept is commonly used to correlate marine and lacustrine strata. However, in the alluvial domain, its use is more challenging because internal, local dynamics controlling sedimentation may interfere with the expression of cyclic climate forcing. Intervals of low net-to-gross may be important for successful application in this domain as they tend to better document regional changes. This study applies climate-based stratigraphic correlation concepts to improve well correlations, characterise vertical sand distribution, and identify potential reservoir targets in a generally low net-to-gross interval. Coarsening upward sedimentary repetitions (cyclothems) are identified and correlated with high certainty in nineteen well sections in the upper Carboniferous Westoe and Cleaver formations of the Silverpit Basin. Local sedimentary dynamics provide variability in the character of the cyclothems and several types of cyclothem are classified. Correlation of sections using cyclothems recognised on wireline logs is done twice: once manually and once semi-automatically. The semi-automated correlation is based on calculation of deviation curves which depict stratigraphic changes that are less dependent on absolute wireline values and follow vertical trends more clearly. The correlations provide composite stratigraphies that are analysed using vertical proportions curves. Both approaches yield similar results in terms of stratigraphic trends. However, for detailed correlation of wells, the manual correlation is better at accounting for any local variability within the system. The same two zones of higher net-to-gross ratios are found using both correlation methods. These are linked to palaeoclimatic changes driven by long eccentricity and the proposed climate stratigraphic model has predictive value for identifying sandstone occurrence. The climate-based stratigraphic correlation improves the assessment reservoir distribution and properties on small (10–20 m thickness) and large (100–200 m thickness) stratigraphical scales.","PeriodicalId":49768,"journal":{"name":"Netherlands Journal of Geosciences-Geologie En Mijnbouw","volume":null,"pages":null},"PeriodicalIF":2.7,"publicationDate":"2023-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77155226","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
G. A. Hutka, M. Cacace, H. Hofmann, Bakul Mathur, A. Zang
Abstract The utilisation of geothermal energy in the Netherlands is primarily focused on deep sedimentary aquifers, which are often intersected by major faults. Geothermal operations (i.e. fluid production and injection) may alter the effective stress state along these faults and trigger induced seismic events. Pore pressure perturbations have been generally considered the main driver of injection-induced seismicity. However, thermal stresses caused by temperature gradients between the re-injected cold fluid and the reservoir rock may also contribute to the triggering of earthquakes in geothermal reservoirs. While existing geothermal power plants operating in sandstone reservoirs did not produce any major induced seismicity, it is a matter of debate whether a reduction in the temperature of the re-injected fluid could increase the seismic hazard potential. In this study, we applied modified Gutenberg–Richter statistics based on frictional Coulomb stress variations implemented in a coupled thermo-hydro-mechanical model to estimate the seismic hazard caused by the operation of a geothermal doublet. We conducted a systematic parametric study to assess and rank the impact of different intrinsic (geological) and extrinsic (operational) parameters on the induced seismic hazard potential. We identified a competing mechanism between induced variations in pore pressure and thermal stress within the reservoir in controlling induced seismicity. We found that stress changes induced by pore pressure variations are the main cause of seismic hazard, although thermally induced stresses also contribute significantly. The results indicate that by optimising the operational parameters it is possible to increase production efficiency while maintaining a long-term control over the fluid injection-induced seismicity.
{"title":"Investigating seismicity rates with Coulomb failure stress models caused by pore pressure and thermal stress from operating a well doublet in a generic geothermal reservoir in the Netherlands","authors":"G. A. Hutka, M. Cacace, H. Hofmann, Bakul Mathur, A. Zang","doi":"10.1017/njg.2023.7","DOIUrl":"https://doi.org/10.1017/njg.2023.7","url":null,"abstract":"Abstract The utilisation of geothermal energy in the Netherlands is primarily focused on deep sedimentary aquifers, which are often intersected by major faults. Geothermal operations (i.e. fluid production and injection) may alter the effective stress state along these faults and trigger induced seismic events. Pore pressure perturbations have been generally considered the main driver of injection-induced seismicity. However, thermal stresses caused by temperature gradients between the re-injected cold fluid and the reservoir rock may also contribute to the triggering of earthquakes in geothermal reservoirs. While existing geothermal power plants operating in sandstone reservoirs did not produce any major induced seismicity, it is a matter of debate whether a reduction in the temperature of the re-injected fluid could increase the seismic hazard potential. In this study, we applied modified Gutenberg–Richter statistics based on frictional Coulomb stress variations implemented in a coupled thermo-hydro-mechanical model to estimate the seismic hazard caused by the operation of a geothermal doublet. We conducted a systematic parametric study to assess and rank the impact of different intrinsic (geological) and extrinsic (operational) parameters on the induced seismic hazard potential. We identified a competing mechanism between induced variations in pore pressure and thermal stress within the reservoir in controlling induced seismicity. We found that stress changes induced by pore pressure variations are the main cause of seismic hazard, although thermally induced stresses also contribute significantly. The results indicate that by optimising the operational parameters it is possible to increase production efficiency while maintaining a long-term control over the fluid injection-induced seismicity.","PeriodicalId":49768,"journal":{"name":"Netherlands Journal of Geosciences-Geologie En Mijnbouw","volume":null,"pages":null},"PeriodicalIF":2.7,"publicationDate":"2023-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84797866","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract The Netherlands is in the midst of an energy transition with hydrocarbon production gradually declining, whereas the role of sustainable energy technologies is on the rise. One of these technologies is geothermal energy production from porous reservoirs at 1.5–3 km depth. As the number of geothermal projects increases, there is a growing concern that felt and/or damaging induced seismic events could occur as a result of geothermal operations. Over the last two decades, such events have occurred in the Netherlands due to gas production, notably in the Groningen gas field. However, the occurrence of felt events is limited to hydrocarbon fields in certain regions or reservoirs. Understanding where and for which plays these events are observed helps to estimate seismogenic potential for geothermal operations and other sustainable subsurface activities. Here, we summarise and review the main similarities and differences in terms of geological and geomechanical characteristics between the hydrocarbon and geothermal plays in the Netherlands, and we consider the differences in pressure and temperature changes. By doing so, we provide better insights into the factors that could play a role for fault reactivation and induced seismicity, and how these differ for hydrocarbon production and geothermal operations in the Netherlands. The review shows that geological characteristics for most geothermal target reservoirs are similar to those of hydrocarbon, albeit geothermal projects so far target higher porosity rocks than hydrocarbon reservoirs. On the other hand, pressure and temperature changes are very different, with significant depletion for hydrocarbon fields vs significant cooling around geothermal injection wells. The different operations result not only in different expected stress change magnitudes but also in a distinct spatio-temporal stress build-up on faults, which has implications for seismogenic potential and monitoring of these different operations.
{"title":"Comparison of hydrocarbon and geothermal energy production in the Netherlands: reservoir characteristics, pressure and temperature changes, and implications for fault reactivation","authors":"L. Buijze, H. Veldkamp, B. Wassing","doi":"10.1017/njg.2023.6","DOIUrl":"https://doi.org/10.1017/njg.2023.6","url":null,"abstract":"Abstract The Netherlands is in the midst of an energy transition with hydrocarbon production gradually declining, whereas the role of sustainable energy technologies is on the rise. One of these technologies is geothermal energy production from porous reservoirs at 1.5–3 km depth. As the number of geothermal projects increases, there is a growing concern that felt and/or damaging induced seismic events could occur as a result of geothermal operations. Over the last two decades, such events have occurred in the Netherlands due to gas production, notably in the Groningen gas field. However, the occurrence of felt events is limited to hydrocarbon fields in certain regions or reservoirs. Understanding where and for which plays these events are observed helps to estimate seismogenic potential for geothermal operations and other sustainable subsurface activities. Here, we summarise and review the main similarities and differences in terms of geological and geomechanical characteristics between the hydrocarbon and geothermal plays in the Netherlands, and we consider the differences in pressure and temperature changes. By doing so, we provide better insights into the factors that could play a role for fault reactivation and induced seismicity, and how these differ for hydrocarbon production and geothermal operations in the Netherlands. The review shows that geological characteristics for most geothermal target reservoirs are similar to those of hydrocarbon, albeit geothermal projects so far target higher porosity rocks than hydrocarbon reservoirs. On the other hand, pressure and temperature changes are very different, with significant depletion for hydrocarbon fields vs significant cooling around geothermal injection wells. The different operations result not only in different expected stress change magnitudes but also in a distinct spatio-temporal stress build-up on faults, which has implications for seismogenic potential and monitoring of these different operations.","PeriodicalId":49768,"journal":{"name":"Netherlands Journal of Geosciences-Geologie En Mijnbouw","volume":null,"pages":null},"PeriodicalIF":2.7,"publicationDate":"2023-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79166202","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jelle J.A. Heere, J. Wallaard, E. Mulder, Jasper Ponstein, A. Schulp
Abstract A mandible of a Late Cretaceous sea turtle with affinities to Ctenochelys is reported from the Maastrichtian type area of the Netherlands. The triangular mandible has a well-developed symphyseal ridge surrounded on both sides by large, concave areas on the triturating surface. It represents the first potential occurrence of Ctenochelys from the Maastrichtian type area. This finding increases the diversity of the turtle fauna known from the Maastrichtian type area.
{"title":"The first report of Chelonioidea cf. Ctenochelys from the Late Cretaceous of the Maastrichtian type area","authors":"Jelle J.A. Heere, J. Wallaard, E. Mulder, Jasper Ponstein, A. Schulp","doi":"10.1017/njg.2023.3","DOIUrl":"https://doi.org/10.1017/njg.2023.3","url":null,"abstract":"Abstract A mandible of a Late Cretaceous sea turtle with affinities to Ctenochelys is reported from the Maastrichtian type area of the Netherlands. The triangular mandible has a well-developed symphyseal ridge surrounded on both sides by large, concave areas on the triturating surface. It represents the first potential occurrence of Ctenochelys from the Maastrichtian type area. This finding increases the diversity of the turtle fauna known from the Maastrichtian type area.","PeriodicalId":49768,"journal":{"name":"Netherlands Journal of Geosciences-Geologie En Mijnbouw","volume":null,"pages":null},"PeriodicalIF":2.7,"publicationDate":"2023-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90872683","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
S. M. Knaake, E. Stouthamer, M. Straatsma, Y. Huismans, K. Cohen, H. Middelkoop
Abstract Scour holes are common features in deltaic rivers which can destabilise embankments through oversteepening of the river bed. Their development has been studied extensively from the hydraulic perspective, but another important control is the erodibility of the river bed which varies considerably due to thickening of heterogeneous deltaic substrate towards the coast. Therefore, we assessed the influence of delta-scale geological heterogeneity and local subsurface architecture on scour hole formation in addition to the hydrodynamic controls. We (1) created an inventory of 165 scour hole locations in the Rhine–Meuse delta, (2) assessed the hydrodynamic conditions at the locations, (3) extracted geometric characteristics and (4) determined the subsurface architecture from geological data. Central and lower delta branches have 0.6–0.7 scours per km while upper delta branches have less than 0.2. Downstream, 58% of scour holes were related to architectural elements, notably sand bodies from former Holocene channel belts and Early Holocene cohesive beds. These scours have steeper slopes due to higher proportions of cohesive sediments near the river bed. Furthermore, scours related to channel belt sand bodies are limited in downstream length and depth, up to maximum of approximately two times the water depth. From our results, we provide a delta-scale explanatory framework that relates the position of present-day river channels with respect to Pleistocene river deposits and Holocene fluvio-deltaic deposits to scour hole formation. Upstream rivers are incised in Pleistocene deposits showing less local variation in erodibility. The majority of scour holes here relate to engineering works. In central and lower delta branches, geologically inherited heterogeneity of the Holocene substrate at critical depths near the channel bottom adds to anthropogenic induced scours and results in high abundances. This demonstrates that downstream variation in subsurface architecture should be considered as a key control on scour locations and characteristics for management purposes.
{"title":"The influence of subsurface architecture on scour hole formation in the Rhine–Meuse delta, the Netherlands","authors":"S. M. Knaake, E. Stouthamer, M. Straatsma, Y. Huismans, K. Cohen, H. Middelkoop","doi":"10.1017/njg.2023.5","DOIUrl":"https://doi.org/10.1017/njg.2023.5","url":null,"abstract":"Abstract Scour holes are common features in deltaic rivers which can destabilise embankments through oversteepening of the river bed. Their development has been studied extensively from the hydraulic perspective, but another important control is the erodibility of the river bed which varies considerably due to thickening of heterogeneous deltaic substrate towards the coast. Therefore, we assessed the influence of delta-scale geological heterogeneity and local subsurface architecture on scour hole formation in addition to the hydrodynamic controls. We (1) created an inventory of 165 scour hole locations in the Rhine–Meuse delta, (2) assessed the hydrodynamic conditions at the locations, (3) extracted geometric characteristics and (4) determined the subsurface architecture from geological data. Central and lower delta branches have 0.6–0.7 scours per km while upper delta branches have less than 0.2. Downstream, 58% of scour holes were related to architectural elements, notably sand bodies from former Holocene channel belts and Early Holocene cohesive beds. These scours have steeper slopes due to higher proportions of cohesive sediments near the river bed. Furthermore, scours related to channel belt sand bodies are limited in downstream length and depth, up to maximum of approximately two times the water depth. From our results, we provide a delta-scale explanatory framework that relates the position of present-day river channels with respect to Pleistocene river deposits and Holocene fluvio-deltaic deposits to scour hole formation. Upstream rivers are incised in Pleistocene deposits showing less local variation in erodibility. The majority of scour holes here relate to engineering works. In central and lower delta branches, geologically inherited heterogeneity of the Holocene substrate at critical depths near the channel bottom adds to anthropogenic induced scours and results in high abundances. This demonstrates that downstream variation in subsurface architecture should be considered as a key control on scour locations and characteristics for management purposes.","PeriodicalId":49768,"journal":{"name":"Netherlands Journal of Geosciences-Geologie En Mijnbouw","volume":null,"pages":null},"PeriodicalIF":2.7,"publicationDate":"2023-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82850009","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Simon Maximilian Müller, F. Jähne-Klingberg, Hauke Thöle, F. Jakobsen, F. Bense, J. Winsemann, C. Gaedicke
Abstract The Central Graben is a Mesozoic sedimentary basin that is significantly influenced by rift and salt tectonics. Its southern part is located in the German and Dutch sectors of the North Sea. Even though studies exist on the tectonic and stratigraphic development of the Danish and Dutch Central Graben, the German Central Graben as an important link is less investigated. We aim to fill this gap and to investigate the sedimentary development from the Latest Triassic to the Early Cretaceous, the relative influence of salt and rift tectonics on subsidence and how our results fit into the existing studies of the Danish and Dutch Central Graben. Knowledge of the development of the graben and its sedimentation is critical for any possible economic use like hydrocarbon exploitation or carbon capture and storage. Therefore, we mapped nine laterally traceable horizons on 2D and 3D reflection seismic data from the Lower Jurassic to the Lower Cretaceous within the German Central Graben and adjacent Danish Salt Dome Province as well as the northern Dutch Central Graben. These horizons include the base horizons of four tectonostratigraphic mega-sequences of the southern Central Graben adopted from the current Dutch tectonostratigraphic concept. Based on the mapping results, we constructed subsidence, thickness and erosion maps of the tectonostratigraphic mega-sequences and their subdivisions. The tectonostratigraphic mega-sequences were then correlated with well logs to determine the lithology. The results show that the structural and stratigraphic architecture of the German Central Graben was consecutively dominated by either subsidence controlled by rifting, salt tectonics or by thermal uplift and subsidence. We suggest that the German Central Graben is divided by a large strike-slip fault zone, the Mid Central Graben Transverse Zone, into a northern part that geologically rather belongs to the Danish and a southern part that rather belongs to the Dutch Central Graben. We discuss how this division and the tectonics influenced the regional lithology.
{"title":"Jurassic to Lower Cretaceous tectonostratigraphy of the German Central Graben, southern North Sea","authors":"Simon Maximilian Müller, F. Jähne-Klingberg, Hauke Thöle, F. Jakobsen, F. Bense, J. Winsemann, C. Gaedicke","doi":"10.1017/njg.2023.4","DOIUrl":"https://doi.org/10.1017/njg.2023.4","url":null,"abstract":"Abstract The Central Graben is a Mesozoic sedimentary basin that is significantly influenced by rift and salt tectonics. Its southern part is located in the German and Dutch sectors of the North Sea. Even though studies exist on the tectonic and stratigraphic development of the Danish and Dutch Central Graben, the German Central Graben as an important link is less investigated. We aim to fill this gap and to investigate the sedimentary development from the Latest Triassic to the Early Cretaceous, the relative influence of salt and rift tectonics on subsidence and how our results fit into the existing studies of the Danish and Dutch Central Graben. Knowledge of the development of the graben and its sedimentation is critical for any possible economic use like hydrocarbon exploitation or carbon capture and storage. Therefore, we mapped nine laterally traceable horizons on 2D and 3D reflection seismic data from the Lower Jurassic to the Lower Cretaceous within the German Central Graben and adjacent Danish Salt Dome Province as well as the northern Dutch Central Graben. These horizons include the base horizons of four tectonostratigraphic mega-sequences of the southern Central Graben adopted from the current Dutch tectonostratigraphic concept. Based on the mapping results, we constructed subsidence, thickness and erosion maps of the tectonostratigraphic mega-sequences and their subdivisions. The tectonostratigraphic mega-sequences were then correlated with well logs to determine the lithology. The results show that the structural and stratigraphic architecture of the German Central Graben was consecutively dominated by either subsidence controlled by rifting, salt tectonics or by thermal uplift and subsidence. We suggest that the German Central Graben is divided by a large strike-slip fault zone, the Mid Central Graben Transverse Zone, into a northern part that geologically rather belongs to the Danish and a southern part that rather belongs to the Dutch Central Graben. We discuss how this division and the tectonics influenced the regional lithology.","PeriodicalId":49768,"journal":{"name":"Netherlands Journal of Geosciences-Geologie En Mijnbouw","volume":null,"pages":null},"PeriodicalIF":2.7,"publicationDate":"2023-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84067700","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
F. Wesselingh, T. Meijer, R. Harting, M. Bakker, F. Busschers
Abstract We report a marine Middle Pleistocene mollusc fauna from a borehole near Luxwoude (Friesland, northern Netherlands). The fauna contains several species, including Bittium species, Acanthocardia paucicostata and Polititapes senescens, that hitherto have been used as indicative for warm (lusitanian) conditions in the southern North Sea Basin during the Late Pleistocene Eemian (MIS5e) interglacial. However, the stratigraphic context of the Luxwoude marine fauna indicates a MIS11 or older age for this new fauna. This thermophilous fauna demonstrates very warm-temperate conditions and probably an open marine connection through the Dover Strait towards the south, during this Middle Pleistocene interglacial. In the North Sea basin, this distinctive lusitanian fauna with Bittium-dominated assemblages can therefore no longer be presumed to be of Eemian age without additional evidence.
{"title":"New marine warm-temperate molluscan assemblage demonstrates warm conditions during the Middle Pleistocene of the North Sea Basin","authors":"F. Wesselingh, T. Meijer, R. Harting, M. Bakker, F. Busschers","doi":"10.1017/njg.2023.1","DOIUrl":"https://doi.org/10.1017/njg.2023.1","url":null,"abstract":"Abstract We report a marine Middle Pleistocene mollusc fauna from a borehole near Luxwoude (Friesland, northern Netherlands). The fauna contains several species, including Bittium species, Acanthocardia paucicostata and Polititapes senescens, that hitherto have been used as indicative for warm (lusitanian) conditions in the southern North Sea Basin during the Late Pleistocene Eemian (MIS5e) interglacial. However, the stratigraphic context of the Luxwoude marine fauna indicates a MIS11 or older age for this new fauna. This thermophilous fauna demonstrates very warm-temperate conditions and probably an open marine connection through the Dover Strait towards the south, during this Middle Pleistocene interglacial. In the North Sea basin, this distinctive lusitanian fauna with Bittium-dominated assemblages can therefore no longer be presumed to be of Eemian age without additional evidence.","PeriodicalId":49768,"journal":{"name":"Netherlands Journal of Geosciences-Geologie En Mijnbouw","volume":null,"pages":null},"PeriodicalIF":2.7,"publicationDate":"2023-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85103042","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. Klompmaker, T. V. van Eldijk, H. Winkelhorst, J. Reumer
Abstract Horseshoe crabs (Xiphosura) have a long evolutionary history starting in the Ordovician, but they have rarely been reported from the Netherlands. We report on the first Triassic horseshoe crab from the Netherlands identifiable to the species level, a specimen of the limulid Limulitella bronnii. We provide the first diagnosis for this species and refigure the holotype. The new specimen was found in the Middle Triassic (Anisian) Muschelkalk sediments of the Vossenveld Formation, in the Illyrian part of the stratigraphic profile of the Winterswijk quarry complex. The Winterswijk specimen represents the youngest occurrence of L. bronnii. The inferred non-marine habitat of this horseshoe crab species elsewhere in conjunction with occurrences of plant and insect remains within the same layer at Winterswijk suggest the specimen herein most probably did not live in marine conditions either. This species has previously been found in non-marine sediments in France and Germany, expanding its geographic range northward. Several faunal elements from Winterswijk including L. bronnii show resemblance to the roughly co-eval non-marine components of the Anisian Grès à Voltzia Formation in NE France, suggesting a paleobiogeographic connection between these regions in Western Europe.
马蹄蟹(Xiphosura)自奥陶纪起就有悠久的进化史，但在荷兰的报道却很少。我们报告了荷兰三叠纪马蹄蟹的第一种可识别的物种水平，limulid Limulitella bronnii标本。我们为这个物种提供了第一个诊断，并重新绘制了全型。这个新标本是在Winterswijk采石场地层剖面的伊利里亚部分，在Vossenveld组的中三叠世(anisiian) Muschelkalk沉积物中发现的。Winterswijk标本代表了最年轻的L. bronnii。推断出这种马蹄蟹在其他地方的非海洋栖息地，以及在Winterswijk同一层内出现的植物和昆虫遗骸，表明这里的标本很可能也没有生活在海洋环境中。这个物种以前在法国和德国的非海洋沉积物中被发现，扩大了其地理范围向北。包括L. bronnii在内的Winterswijk的一些动物成分与法国东北部的Anisian gr - Voltzia组的大致共同评估的非海洋成分相似，表明这些地区在西欧之间存在古生物地理联系。
{"title":"A non-marine horseshoe crab from the Middle Triassic (Anisian) of the Netherlands","authors":"A. Klompmaker, T. V. van Eldijk, H. Winkelhorst, J. Reumer","doi":"10.1017/njg.2022.16","DOIUrl":"https://doi.org/10.1017/njg.2022.16","url":null,"abstract":"Abstract Horseshoe crabs (Xiphosura) have a long evolutionary history starting in the Ordovician, but they have rarely been reported from the Netherlands. We report on the first Triassic horseshoe crab from the Netherlands identifiable to the species level, a specimen of the limulid Limulitella bronnii. We provide the first diagnosis for this species and refigure the holotype. The new specimen was found in the Middle Triassic (Anisian) Muschelkalk sediments of the Vossenveld Formation, in the Illyrian part of the stratigraphic profile of the Winterswijk quarry complex. The Winterswijk specimen represents the youngest occurrence of L. bronnii. The inferred non-marine habitat of this horseshoe crab species elsewhere in conjunction with occurrences of plant and insect remains within the same layer at Winterswijk suggest the specimen herein most probably did not live in marine conditions either. This species has previously been found in non-marine sediments in France and Germany, expanding its geographic range northward. Several faunal elements from Winterswijk including L. bronnii show resemblance to the roughly co-eval non-marine components of the Anisian Grès à Voltzia Formation in NE France, suggesting a paleobiogeographic connection between these regions in Western Europe.","PeriodicalId":49768,"journal":{"name":"Netherlands Journal of Geosciences-Geologie En Mijnbouw","volume":null,"pages":null},"PeriodicalIF":2.7,"publicationDate":"2023-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85051954","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract From dynamic rupture simulations, we reveal under which conditions a rupture in the Groningen gas field stops along fault dip or along fault strike after it starts on a fault in the reservoir. The simulations focus on the capabilities of fault plane irregularities to arrest ruptures. Such irregularities can be recognised in sandstone outcrops. Fault planes in the Groningen field, extracted from the 3D seismic data by seismic attribute extraction methods, show similar irregularities. A detailed surface of a major fault plane in the field indicates that steps and jogs of tenths of metres are possible. Although these irregularities are close to seismic resolution and could be partially artificial, we investigated their effect on rupture arrest. For typical current stresses in the Groningen field, jogs and steps of this length scale are found to be remarkably effective to stop ruptures in the reservoir. Also, a significant increase in the fault dip along fault strike can stop these ruptures but a kink in the fault under a constant fault dip not. Including non-planar fault features and pressure diffusion in the Carboniferous, the simulations in this paper follow trends of previous simulations in the literature using 2D planar faults. In particular, the horizontal stress in this formation and the strength of the Carboniferous fault zone are important for rupture propagation. If the fault would have been reactivated in the Neogene or Quaternary and poorly healed in clay-rich parts, rupture propagation into the Carboniferous can only be prevented by jogs of sufficient size and lateral continuity under the present estimate of the horizontal field stress.
{"title":"Induced seismicity in the Groningen gas field – arrest of ruptures by fault plane irregularities","authors":"H. M. Wentinck, M. Kortekaas","doi":"10.1017/njg.2023.9","DOIUrl":"https://doi.org/10.1017/njg.2023.9","url":null,"abstract":"Abstract From dynamic rupture simulations, we reveal under which conditions a rupture in the Groningen gas field stops along fault dip or along fault strike after it starts on a fault in the reservoir. The simulations focus on the capabilities of fault plane irregularities to arrest ruptures. Such irregularities can be recognised in sandstone outcrops. Fault planes in the Groningen field, extracted from the 3D seismic data by seismic attribute extraction methods, show similar irregularities. A detailed surface of a major fault plane in the field indicates that steps and jogs of tenths of metres are possible. Although these irregularities are close to seismic resolution and could be partially artificial, we investigated their effect on rupture arrest. For typical current stresses in the Groningen field, jogs and steps of this length scale are found to be remarkably effective to stop ruptures in the reservoir. Also, a significant increase in the fault dip along fault strike can stop these ruptures but a kink in the fault under a constant fault dip not. Including non-planar fault features and pressure diffusion in the Carboniferous, the simulations in this paper follow trends of previous simulations in the literature using 2D planar faults. In particular, the horizontal stress in this formation and the strength of the Carboniferous fault zone are important for rupture propagation. If the fault would have been reactivated in the Neogene or Quaternary and poorly healed in clay-rich parts, rupture propagation into the Carboniferous can only be prevented by jogs of sufficient size and lateral continuity under the present estimate of the horizontal field stress.","PeriodicalId":49768,"journal":{"name":"Netherlands Journal of Geosciences-Geologie En Mijnbouw","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135562865","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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