J. Emmings, J. Parnell, M. H. Stephenson, B. Lodhia
This volume showcases recent geological, geophysical, and geochemical research on the Carboniferous Bowland Shale Formation, a classic Palaeozoic black shale unit. The Bowland Shale spans ca. 16 Myrs from the upper Visean to mid-Bashkirian, and is perhaps the most important and controversial black shale unit in the UK. The volume focuses on the key Carboniferous basins in the Midlands, northern England, and North Wales. The main basins assessed in the volume are the Craven Basin, including the Bowland sub-basin, the Blacon Basin, the Edale Basin, the Widmerpool Gulf and the Gainsborough Trough. The Bowland Shale and equivalent units are described and interpreted in terms of sedimentary, geochemical, and physical properties and processes, basin-forming events, hydrocarbon prospectivity, mineralization, and heat and fluid flow in the subsurface.
{"title":"Introduction to The Bowland Shale Formation, UK: Processes and Resources","authors":"J. Emmings, J. Parnell, M. H. Stephenson, B. Lodhia","doi":"10.1144/sp534-2023-142","DOIUrl":"https://doi.org/10.1144/sp534-2023-142","url":null,"abstract":"\u0000 This volume showcases recent geological, geophysical, and geochemical research on the Carboniferous Bowland Shale Formation, a classic Palaeozoic black shale unit. The Bowland Shale spans ca. 16 Myrs from the upper Visean to mid-Bashkirian, and is perhaps the most important and controversial black shale unit in the UK. The volume focuses on the key Carboniferous basins in the Midlands, northern England, and North Wales. The main basins assessed in the volume are the Craven Basin, including the Bowland sub-basin, the Blacon Basin, the Edale Basin, the Widmerpool Gulf and the Gainsborough Trough. The Bowland Shale and equivalent units are described and interpreted in terms of sedimentary, geochemical, and physical properties and processes, basin-forming events, hydrocarbon prospectivity, mineralization, and heat and fluid flow in the subsurface.","PeriodicalId":281618,"journal":{"name":"Geological Society, London, Special Publications","volume":"48 9","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140487478","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The Falls of the Ohio is a world-renowned geoheritage site of palaeontological and geological importance that also played key roles in the cultural and historical development of America. Studied by geologists for over two centuries, over 600 species of fossils are known from the site, hundreds which were first described here. Beyond geology, the Falls of the Ohio can also be considered the origin and ending of the Lewis and Clark expedition, as well as an important location for naturalists and educators. A treasure of natural and human history and a National Natural Landmark, this spectacular 220-acre expanse of fossiliferous bedrock is worthy of ongoing study and protection.
{"title":"The Falls of the Ohio River: America's First Fossil Bed","authors":"Alan Goldstein, Katherine V. Bulinski","doi":"10.1144/sp543-2022-240","DOIUrl":"https://doi.org/10.1144/sp543-2022-240","url":null,"abstract":"\u0000 The Falls of the Ohio is a world-renowned geoheritage site of palaeontological and geological importance that also played key roles in the cultural and historical development of America. Studied by geologists for over two centuries, over 600 species of fossils are known from the site, hundreds which were first described here. Beyond geology, the Falls of the Ohio can also be considered the origin and ending of the Lewis and Clark expedition, as well as an important location for naturalists and educators. A treasure of natural and human history and a National Natural Landmark, this spectacular 220-acre expanse of fossiliferous bedrock is worthy of ongoing study and protection.","PeriodicalId":281618,"journal":{"name":"Geological Society, London, Special Publications","volume":"1 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139593280","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
K. S. Choi, J. Jo, D. H. Kim, S. Y. Sohn, S. H. Bang
Tidal channels exert a crucial control on sediment transport and drive geomorphic changes in the tidal environment. Despite their ubiquitous occurrence, long-term morphodynamics and processes driving the morphologic changes remain less well understood than fluvial counterparts. Spanning from straight to dendritic, Korean tidal channels become more sinuous and densely populated with elevation due to higher mud content. Mutually evasive current patterns resulted in a cuspate meander bend, where flood barb develops at the seaward side of the bend. Multiannual observation revealed that tidal channels migrate up to 80 m per year in the lower intertidal zone of open-coast sandy tidal flats to nearly stationary for several years in the upper intertidal zone of protected muddy tidal flats. Migration rates are temporarily pronounced during the summer monsoon when heavy rainfall-induced surface runoff intensifies ebb tidal asymmetry and promotes headward erosion. Meander bends are mostly landward-skewed and shift downstream, implying that ebb currents primarily drive the long-term channel morphodynamics. Tidal point bars commonly display ebbwardly dipping, inclined heterolithic stratification (IHS), dominated by bedforms formed by subordinate flood tidal currents. An overall ebb-dominance and mutually evasive current patterns account for the counterintuitive stratigraphic architecture of the point bars in Korean tidal channels.
{"title":"Morphodynamics of macrotidal channels in Korean tidal flats: implications for the role of monsoon precipitation and the stratigraphic architecture of tidal point bars","authors":"K. S. Choi, J. Jo, D. H. Kim, S. Y. Sohn, S. H. Bang","doi":"10.1144/sp540-2023-113","DOIUrl":"https://doi.org/10.1144/sp540-2023-113","url":null,"abstract":"\u0000 Tidal channels exert a crucial control on sediment transport and drive geomorphic changes in the tidal environment. Despite their ubiquitous occurrence, long-term morphodynamics and processes driving the morphologic changes remain less well understood than fluvial counterparts. Spanning from straight to dendritic, Korean tidal channels become more sinuous and densely populated with elevation due to higher mud content. Mutually evasive current patterns resulted in a cuspate meander bend, where flood barb develops at the seaward side of the bend. Multiannual observation revealed that tidal channels migrate up to 80 m per year in the lower intertidal zone of open-coast sandy tidal flats to nearly stationary for several years in the upper intertidal zone of protected muddy tidal flats. Migration rates are temporarily pronounced during the summer monsoon when heavy rainfall-induced surface runoff intensifies ebb tidal asymmetry and promotes headward erosion. Meander bends are mostly landward-skewed and shift downstream, implying that ebb currents primarily drive the long-term channel morphodynamics. Tidal point bars commonly display ebbwardly dipping, inclined heterolithic stratification (IHS), dominated by bedforms formed by subordinate flood tidal currents. An overall ebb-dominance and mutually evasive current patterns account for the counterintuitive stratigraphic architecture of the point bars in Korean tidal channels.","PeriodicalId":281618,"journal":{"name":"Geological Society, London, Special Publications","volume":"58 42","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139598478","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
J. Palma, Ole Rabbel, J. Spacapan, Remigio Ruiz, O. Galland
This contribution presents a detailed geological study of a well-exposed igneous petroleum system at Sierra de Cara Cura, Neuquén basin, Argentina, which consists of sills, dykes, laccoliths and hybrid intrusion morphologies. The size of the exposed intrusive complex (19 km in N-S direction) is similar to those of sill-clusters hosting producing oil fields of the nearby Río Grande Valley. Most sills (>80%) are preferentially emplaced in the organic-rich rocks such as Vaca Muerta and Agrio Formations. Sills are extensively fractured and represent potentially good fractured hydrocarbon reservoirs. We document several fracturing mechanisms that can lead to heterogeneous fracture distribution. Laccoliths represent very different igneous reservoirs with a typical zonation: the core of the laccoliths are massive and poorly fractured, whereas the rims consist of a breccia formed during laccolith emplacement. The Vaca Muerta and Agrio Formations are thermally altered by the cooling of the sills. The deep parts of the outcropping laccoliths likely altered thermally the shale formations they were emplaced in. Hydrogen Index (HI) and Transformation Ratio (TR) of the organic matter are the best parameters to determine the thickness of the thermal aureole. The Sierra de Cara Cura appears as a world-class field analogue of igneous petroleum systems.
本文介绍了对阿根廷内乌肯盆地 Sierra de Cara Cura 一个出露较好的火成岩石油系统的详细地质研究，该系统由岩屑、岩决、裂隙和混合侵入形态组成。裸露的侵入复合体（南北方向 19 公里）的大小与附近格兰德河谷产油油田所在的岩浆群相似。大多数岩屑（大于 80%）都优先堆积在富含有机质的岩石中，如瓦卡穆埃尔塔地层和阿格里奥地层。山体断裂广泛，是潜在的良好断裂碳氢化合物储层。我们记录了几种可导致异质断裂分布的断裂机制。裂隙岩代表着截然不同的火成岩储层，具有典型的分带现象：裂隙岩的岩心是块状的，断裂情况较差，而岩缘则由裂隙岩形成过程中形成的角砾岩组成。瓦卡穆埃尔塔地层和阿格里奥地层因岩屑冷却而发生热变。出露裂隙岩的深部很可能热蚀变了它们所处的页岩层。有机质的氢指数（HI）和转化率（TR）是确定热蚀变厚度的最佳参数。卡拉库拉山脉似乎是火成岩石油系统的一个世界级实地类比。
{"title":"The Cara Cura intrusive complex, Neuquén Basin, Argentina: a field analogue of a whole igneous petroleum system","authors":"J. Palma, Ole Rabbel, J. Spacapan, Remigio Ruiz, O. Galland","doi":"10.1144/sp547-2023-119","DOIUrl":"https://doi.org/10.1144/sp547-2023-119","url":null,"abstract":"\u0000 This contribution presents a detailed geological study of a well-exposed igneous petroleum system at Sierra de Cara Cura, Neuquén basin, Argentina, which consists of sills, dykes, laccoliths and hybrid intrusion morphologies. The size of the exposed intrusive complex (19 km in N-S direction) is similar to those of sill-clusters hosting producing oil fields of the nearby Río Grande Valley. Most sills (>80%) are preferentially emplaced in the organic-rich rocks such as Vaca Muerta and Agrio Formations. Sills are extensively fractured and represent potentially good fractured hydrocarbon reservoirs. We document several fracturing mechanisms that can lead to heterogeneous fracture distribution. Laccoliths represent very different igneous reservoirs with a typical zonation: the core of the laccoliths are massive and poorly fractured, whereas the rims consist of a breccia formed during laccolith emplacement. The Vaca Muerta and Agrio Formations are thermally altered by the cooling of the sills. The deep parts of the outcropping laccoliths likely altered thermally the shale formations they were emplaced in. Hydrogen Index (HI) and Transformation Ratio (TR) of the organic matter are the best parameters to determine the thickness of the thermal aureole. The Sierra de Cara Cura appears as a world-class field analogue of igneous petroleum systems.","PeriodicalId":281618,"journal":{"name":"Geological Society, London, Special Publications","volume":"34 7","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139599505","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Michael S. Curtis, S. Holford, M. Bunch, N. Schofield, Alex Karvelas
The Northern Carnarvon Basin (NCB) located on Australia's North West Shelf hosts an extensive (∼40,000 km 2 ) intrusive igneous complex related to Mesozoic rifting and breakup. Using an extensive suite of modern 3D seismic reflection surveys, we have mapped this intrusive system across the NCB. We identify three predominant intrusion morphologies: Stacked sheets of large interconnected sill intrusions (up to ∼170 km long) and smaller (8 to 30 km long) isolated, strata concordant intrusions, which often interact with normal faults emplaced into deltaic sedimentary rocks; and variably sized (10 to 40 km long) saucer-shaped intrusions emplaced into marine shales, spread across seven zones (geographically constrained groups of intrusions of a specific morphology). We consider the zones' margin-parallel orientation, suggesting control by sub-crustal extensional processes during rifting; and, variation in intrusion morphology between these zones, suggesting a dominant control by host rock mechanical properties. We integrate previous work with our observations, constraining emplacement to between the Kimmeridgian and Valanginian, coinciding with key phases of margin evolution. Finally, we assess the impact of this intrusive complex on local petroleum systems. There is likely little to no adverse impact on source rock maturation or reservoir contamination by CO 2 . But, there is a spatial dissociation between the location of groups of intrusions and the gas fields, particularly in the Exmouth Plateau; this suggests that migrating hydrocarbons may be blocked, baffled and/or redirected by emplaced igneous rocks.
{"title":"The magma plumbing system of the Northern Carnarvon Basin, offshore Australia: Multi-scale controls on basinwide magma emplacement, and implications for petroleum exploration","authors":"Michael S. Curtis, S. Holford, M. Bunch, N. Schofield, Alex Karvelas","doi":"10.1144/sp547-2023-143","DOIUrl":"https://doi.org/10.1144/sp547-2023-143","url":null,"abstract":"\u0000 \u0000 The Northern Carnarvon Basin (NCB) located on Australia's North West Shelf hosts an extensive (∼40,000 km\u0000 2\u0000 ) intrusive igneous complex related to Mesozoic rifting and breakup. Using an extensive suite of modern 3D seismic reflection surveys, we have mapped this intrusive system across the NCB. We identify three predominant intrusion morphologies: Stacked sheets of large interconnected sill intrusions (up to ∼170 km long) and smaller (8 to 30 km long) isolated, strata concordant intrusions, which often interact with normal faults emplaced into deltaic sedimentary rocks; and variably sized (10 to 40 km long) saucer-shaped intrusions emplaced into marine shales, spread across seven zones (geographically constrained groups of intrusions of a specific morphology). We consider the zones' margin-parallel orientation, suggesting control by sub-crustal extensional processes during rifting; and, variation in intrusion morphology between these zones, suggesting a dominant control by host rock mechanical properties. We integrate previous work with our observations, constraining emplacement to between the Kimmeridgian and Valanginian, coinciding with key phases of margin evolution. Finally, we assess the impact of this intrusive complex on local petroleum systems. There is likely little to no adverse impact on source rock maturation or reservoir contamination by CO\u0000 2\u0000 . But, there is a spatial dissociation between the location of groups of intrusions and the gas fields, particularly in the Exmouth Plateau; this suggests that migrating hydrocarbons may be blocked, baffled and/or redirected by emplaced igneous rocks.\u0000","PeriodicalId":281618,"journal":{"name":"Geological Society, London, Special Publications","volume":"38 9","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139602353","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The recent shale gas revolution originated in the United States in the late 1990s with the exploration of the Carboniferous Barnett Shale in Texas. Success in a number of additional basins in North America such as the Marcellus, Eagleford and Bakken stimulated a search for similar opportunities elsewhere around the world. Amongst the shales and basins targeted by industry was the Carboniferous Bowland Shale (and equivalents) in northern England. An initial premise that the Barnett represented an excellent analogue for the Bowland lead to overoptimistic reserve estimates which have been shown to be largely incorrect. On the basis of visual inspection of wellbore cores, the Carboniferous Barnett and Bowland shales appear to be very similar. Unfortunately, it is there that the similarity ends. Research carried out for the UKUH project has highlighted important differences adversely impacting propectivity. These can be summarised as basin type/continuity and structural complexity. The total organic carbon (TOC), maturity, mineralogy and thickness of the Bowland Shale and equivalents are broadly similar to the successful US examples. Our conclusion is that the Bowland Shale in the UK does not represent a technically significant resource and in hindsight did not merit the considerable industry and media attention that has been associated with it. A key learning is that fundamental research based on heritage data and modern analytical and modelling techniques should have preceded drilling and fracking operations in northern England. Supplementary material at https://doi.org/10.6084/m9.figshare.c.7027899
{"title":"A Review of the Carboniferous Shale Gas Potential of Northern England: A data-based analysis of why it won't work","authors":"A. J. Fraser, B. Lodhia, Michael J. E. Sims","doi":"10.1144/sp534-2023-56","DOIUrl":"https://doi.org/10.1144/sp534-2023-56","url":null,"abstract":"\u0000 The recent shale gas revolution originated in the United States in the late 1990s with the exploration of the Carboniferous Barnett Shale in Texas. Success in a number of additional basins in North America such as the Marcellus, Eagleford and Bakken stimulated a search for similar opportunities elsewhere around the world. Amongst the shales and basins targeted by industry was the Carboniferous Bowland Shale (and equivalents) in northern England.\u0000 An initial premise that the Barnett represented an excellent analogue for the Bowland lead to overoptimistic reserve estimates which have been shown to be largely incorrect. On the basis of visual inspection of wellbore cores, the Carboniferous Barnett and Bowland shales appear to be very similar. Unfortunately, it is there that the similarity ends. Research carried out for the UKUH project has highlighted important differences adversely impacting propectivity. These can be summarised as basin type/continuity and structural complexity. The total organic carbon (TOC), maturity, mineralogy and thickness of the Bowland Shale and equivalents are broadly similar to the successful US examples.\u0000 Our conclusion is that the Bowland Shale in the UK does not represent a technically significant resource and in hindsight did not merit the considerable industry and media attention that has been associated with it. A key learning is that fundamental research based on heritage data and modern analytical and modelling techniques should have preceded drilling and fracking operations in northern England.\u0000 \u0000 Supplementary material at\u0000 https://doi.org/10.6084/m9.figshare.c.7027899\u0000","PeriodicalId":281618,"journal":{"name":"Geological Society, London, Special Publications","volume":"35 9","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139612242","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Grand Caverns is known to be the oldest show cave in continuous operation in the contiguous United States (US). Discovered in 1804, Grand Caverns has been offering tours, at least one per year, continuously from 1806 until now. For more than two centuries Grand Caverns, host to diverse and uncommon solution caves' speleothems such as cave shields, has served as the center of multidisciplinary research related to the understanding limestones in Virginia and has accrued historical accounts relevant to the Shenandoah Valley (nestled between the Blue Ridge Mountains to the east and the Allegheny Mountains to the west) in the Commonwealth of Virginia. In this chapter, we explore the geological, historical, mapping, and geotourism legacies, while using the Geoheritage as a narrative framework. In addition, we discuss the intersection of historical and diverse concurrent heritages at Grand Caverns and the relevance for the understanding of national show caves and caves' development processes; and we share ongoing efforts towards the construction of a proposal to elevate the status of Grand Caverns to be part of the United Nations Educational, Scientific and Cultural Organization (UNESCO) World Heritage list. Supplementary material at https://doi.org/10.6084/m9.figshare.c.7027515
{"title":"Using the Geoheritage Framework to Explore the Intersection of Diverse Legacies at Grand Caverns, Virginia, US","authors":"Ángel A. Garcia, Austin Shank","doi":"10.1144/sp543-2022-221","DOIUrl":"https://doi.org/10.1144/sp543-2022-221","url":null,"abstract":"\u0000 Grand Caverns is known to be the oldest show cave in continuous operation in the contiguous United States (US). Discovered in 1804, Grand Caverns has been offering tours, at least one per year, continuously from 1806 until now. For more than two centuries Grand Caverns, host to diverse and uncommon solution caves' speleothems such as cave shields, has served as the center of multidisciplinary research related to the understanding limestones in Virginia and has accrued historical accounts relevant to the Shenandoah Valley (nestled between the Blue Ridge Mountains to the east and the Allegheny Mountains to the west) in the Commonwealth of Virginia. In this chapter, we explore the geological, historical, mapping, and geotourism legacies, while using the Geoheritage as a narrative framework. In addition, we discuss the intersection of historical and diverse concurrent heritages at Grand Caverns and the relevance for the understanding of national show caves and caves' development processes; and we share ongoing efforts towards the construction of a proposal to elevate the status of Grand Caverns to be part of the United Nations Educational, Scientific and Cultural Organization (UNESCO) World Heritage list.\u0000 \u0000 Supplementary material at\u0000 https://doi.org/10.6084/m9.figshare.c.7027515\u0000","PeriodicalId":281618,"journal":{"name":"Geological Society, London, Special Publications","volume":"70 12","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139613330","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Volcanogenic-sedimentary and coal-bearing deposits, which contain abundant fossils of a lacustrine fauna and terrestrial flora, are widespread in the territory of Transbaikalia (Russia), Mongolia, and Northeastern China. These ecosystems are known under the name of ‘Jehol Biota’, which occurs in the Yixian and Jiufotang formations. The discovery of ‘feathered’ dinosaurs and of the earliest angiosperms in western Liaoning Province (China) made them world famous. The history of this biota began in the nineteenth century, when the discoveries in Transbaikalia of the remains of conchostracans, ostracods, insects, fish, and plants collected during the expedition of A.F. Middendorf were described. The Barremian–Aptian sedimentary sequences of Transbaikalia (Russia), Mongolia, and Northeastern China are very similar. The appearance and evolution of the Jehol Biota occurred against the background of extensive volcanism and tectonic revival, after which normal sedimentary rocks were deposited, culminating in relief peneplanation, swamp development and peat formation. The northern limit of the distribution of this biota is determined as up to about 54° modern north latitude. The existence of the Siberian Jehol Biota in extreme climatic conditions is confirmed, as was indicated for the Jehol Biota from Northeast China.
{"title":"Siberian Jehol Biota","authors":"E. Bugdaeva, L. Golovneva","doi":"10.1144/sp545-2023-155","DOIUrl":"https://doi.org/10.1144/sp545-2023-155","url":null,"abstract":"\u0000 Volcanogenic-sedimentary and coal-bearing deposits, which contain abundant fossils of a lacustrine fauna and terrestrial flora, are widespread in the territory of Transbaikalia (Russia), Mongolia, and Northeastern China. These ecosystems are known under the name of ‘Jehol Biota’, which occurs in the Yixian and Jiufotang formations. The discovery of ‘feathered’ dinosaurs and of the earliest angiosperms in western Liaoning Province (China) made them world famous. The history of this biota began in the nineteenth century, when the discoveries in Transbaikalia of the remains of conchostracans, ostracods, insects, fish, and plants collected during the expedition of A.F. Middendorf were described. The Barremian–Aptian sedimentary sequences of Transbaikalia (Russia), Mongolia, and Northeastern China are very similar. The appearance and evolution of the Jehol Biota occurred against the background of extensive volcanism and tectonic revival, after which normal sedimentary rocks were deposited, culminating in relief peneplanation, swamp development and peat formation. The northern limit of the distribution of this biota is determined as up to about 54° modern north latitude. The existence of the Siberian Jehol Biota in extreme climatic conditions is confirmed, as was indicated for the Jehol Biota from Northeast China.","PeriodicalId":281618,"journal":{"name":"Geological Society, London, Special Publications","volume":"114 22","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139614240","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
L. Percival, H. Matsumoto, S. Callegaro, E. Erba, A. C. Kerr, J. Mutterlose, K. Suzuki
The Cretaceous Period was marked by the formation of numerous Large Igneous Provinces (LIPs), several of which were associated with geologically rapid climate, environmental, and biosphere perturbations, including the early Aptian and latest Cenomanian Oceanic Anoxic Events (OAEs 1a and 2, respectively). In most cases, magmatic CO 2 emissions are thought to have been the major driver of climate and biosphere degradation. This work summarises the relationships between Cretaceous LIPs and environmental perturbations, focussing on how volcanism caused climate warming during OAE 1a using osmium-isotope and mercury concentration data. The new results support magmatic CO 2 output from submarine LIP activity as the primary trigger of climate warming and biosphere stress before/during OAE 1a. This submarine volcanic trigger of OAE 1a (and OAE 2), two of the most climatically/biotically severe Cretaceous events, highlights the capacity of oceanic LIPs to impact Earth's environment as profoundly as many continental provinces. Cretaceous magmatism (and likely output of CO 2 and trace-metal micronutrients) was apparently most intense during those OAEs; further studies are needed to better constrain eruption histories of those oceanic plateaus. Another open question is why the Cretaceous Period overall featured a higher rate of magmatic activity and LIP formation compared to before and afterwards. Supplementary material at https://doi.org/10.6084/m9.figshare.c.7026011
{"title":"Cretaceous Large Igneous Provinces: from volcanic formation to environmental catastrophes and biological crises","authors":"L. Percival, H. Matsumoto, S. Callegaro, E. Erba, A. C. Kerr, J. Mutterlose, K. Suzuki","doi":"10.1144/sp544-2023-88","DOIUrl":"https://doi.org/10.1144/sp544-2023-88","url":null,"abstract":"\u0000 \u0000 The Cretaceous Period was marked by the formation of numerous Large Igneous Provinces (LIPs), several of which were associated with geologically rapid climate, environmental, and biosphere perturbations, including the early Aptian and latest Cenomanian Oceanic Anoxic Events (OAEs 1a and 2, respectively). In most cases, magmatic CO\u0000 2\u0000 emissions are thought to have been the major driver of climate and biosphere degradation. This work summarises the relationships between Cretaceous LIPs and environmental perturbations, focussing on how volcanism caused climate warming during OAE 1a using osmium-isotope and mercury concentration data. The new results support magmatic CO\u0000 2\u0000 output from submarine LIP activity as the primary trigger of climate warming and biosphere stress before/during OAE 1a. This submarine volcanic trigger of OAE 1a (and OAE 2), two of the most climatically/biotically severe Cretaceous events, highlights the capacity of oceanic LIPs to impact Earth's environment as profoundly as many continental provinces. Cretaceous magmatism (and likely output of CO\u0000 2\u0000 and trace-metal micronutrients) was apparently most intense during those OAEs; further studies are needed to better constrain eruption histories of those oceanic plateaus. Another open question is why the Cretaceous Period overall featured a higher rate of magmatic activity and LIP formation compared to before and afterwards.\u0000 \u0000 \u0000 Supplementary material at\u0000 https://doi.org/10.6084/m9.figshare.c.7026011\u0000","PeriodicalId":281618,"journal":{"name":"Geological Society, London, Special Publications","volume":"111 41","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139615599","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The explosive radiation of early birds has been well documented by the extraordinary discoveries of the Early Cretaceous fossil birds from China in the past three decades. They have greatly expanded the diversity, disparity, and temporal distribution of Mesozoic birds, refining our knowledge of the evolutionary path leading to the characteristic avian body plan, such as feathers and powered flight, locomotion and habitat differentiation, diet and digestion, reproduction and development, feather colors and display. In addition, studies on the geological background of the Jehol Biota that produced the majority of the Chinese Cretaceous birds have provided important clues to our understanding of the taphonomy as well as the interaction between deep geology process and biological evolution in northeastern China and East Asia during the Early Cretaceous. Future multidisciplinary studies are expected to advance our knowledge of how the paleogeography of Early Cretaceous birds was formed, what had impacted the changes of the diversity of early birds in China, and the roles of early birds had played in the Early Cretaceous terrestrial ecosystem.
{"title":"Cretaceous fossil birds from China","authors":"Zhonghe Zhou, Min Wang","doi":"10.1144/sp544-2023-129","DOIUrl":"https://doi.org/10.1144/sp544-2023-129","url":null,"abstract":"\u0000 The explosive radiation of early birds has been well documented by the extraordinary discoveries of the Early Cretaceous fossil birds from China in the past three decades. They have greatly expanded the diversity, disparity, and temporal distribution of Mesozoic birds, refining our knowledge of the evolutionary path leading to the characteristic avian body plan, such as feathers and powered flight, locomotion and habitat differentiation, diet and digestion, reproduction and development, feather colors and display. In addition, studies on the geological background of the Jehol Biota that produced the majority of the Chinese Cretaceous birds have provided important clues to our understanding of the taphonomy as well as the interaction between deep geology process and biological evolution in northeastern China and East Asia during the Early Cretaceous. Future multidisciplinary studies are expected to advance our knowledge of how the paleogeography of Early Cretaceous birds was formed, what had impacted the changes of the diversity of early birds in China, and the roles of early birds had played in the Early Cretaceous terrestrial ecosystem.","PeriodicalId":281618,"journal":{"name":"Geological Society, London, Special Publications","volume":"121 46","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139615070","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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