Two species of the closely-related monobathrid crinoid from the Lower Palaeozoic of Scotland, namely Macrostylocrinus cirrifer Ramsbottom (Upper Ordovician, Katian) and Macrostylocrinus silurocirrifer Brower (Lower Silurian, Telychian), are similar in having elongate, unbranched radices proximally. These were not cirri, as suggested by their names, but were radices which were more or less inflexible, lacking contractile tissues. The function of these radices was uncertain. In the absence of contractile tissues, they could not have been for grasping other upright structures and crinoid do not need help to balance, their posture being maintained by mutable collagenous tissues. It is possible, but unlikely, that they may have acted to direct feeding currents towards the crown. Most probably, in an analogy to the post-Palaeozoic isocrinids, the stem acted like a ‘conveyor belt’, the proximal, radicular and upright part being carried away from the cup as further columnals are inserted, eventually forming a distal, recumbent attachment structure. The elongate radices would have stabilised the dististele, but, unlike isocrinids, the arms of Macrostylocrinus spp. were not adapted for crawling and thus escaping predators. Both M. silurocirrifer (type species) and M. cirrifer are included in Macrostylocrinus ( Scotimacrostylocrinus ) subgen. nov.
{"title":"Functional morphology of the stem in the Lower Palaeozoic crinoid\u0000 Macrostylocrinus\u0000 Hall from Scotland","authors":"Stephen K. Donovan","doi":"10.1144/sjg2023-021","DOIUrl":"https://doi.org/10.1144/sjg2023-021","url":null,"abstract":"\u0000 Two species of the closely-related monobathrid crinoid from the Lower Palaeozoic of Scotland, namely\u0000 Macrostylocrinus cirrifer\u0000 Ramsbottom (Upper Ordovician, Katian) and\u0000 Macrostylocrinus silurocirrifer\u0000 Brower (Lower Silurian, Telychian), are similar in having elongate, unbranched radices proximally. These were not cirri, as suggested by their names, but were radices which were more or less inflexible, lacking contractile tissues. The function of these radices was uncertain. In the absence of contractile tissues, they could not have been for grasping other upright structures and crinoid do not need help to balance, their posture being maintained by mutable collagenous tissues. It is possible, but unlikely, that they may have acted to direct feeding currents towards the crown. Most probably, in an analogy to the post-Palaeozoic isocrinids, the stem acted like a ‘conveyor belt’, the proximal, radicular and upright part being carried away from the cup as further columnals are inserted, eventually forming a distal, recumbent attachment structure. The elongate radices would have stabilised the dististele, but, unlike isocrinids, the arms of\u0000 Macrostylocrinus\u0000 spp. were not adapted for crawling and thus escaping predators. Both\u0000 M. silurocirrifer\u0000 (type species) and\u0000 M. cirrifer\u0000 are included in\u0000 Macrostylocrinus\u0000 (\u0000 Scotimacrostylocrinus\u0000 ) subgen. nov.\u0000","PeriodicalId":49556,"journal":{"name":"Scottish Journal of Geology","volume":"13 20","pages":""},"PeriodicalIF":0.7,"publicationDate":"2023-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138980852","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
R. G. Davidson, N. H. Trewin, J. Armstrong, S. R. Waters
The area known as Lethen Bar and Clune, SE of Nairn, Scotland, is a classic Middle Devonian locality which has yielded nodules or concretions, some of which contain fossil fishes with the highest quality of preservation. The locality was largely centred on farm limestone quarries situated around the perimeter of an isolated outlier of the main fishbed. It was first described in the 19 th century, although the upsurge in collecting fossil fishes only occurred some twelve years after the quarries were first mentioned in the scientific literature. Our knowledge of the provenance of the locality is based on very limited accounts, which have never been scientifically tested; these accounts also contain apparent anomalies that have never been adequately addressed. Based on these anomalies, the author of a paper published in 1983 proposed that the locality had been untraceable since the late 19 th century and that the outcrop was quarried out. In 2005, the present authors recorded the first scientifically detailed stratigraphical section of the fishbed, followed in 2021-2023 by detailed field surveys and by a re-appraisal of the literature. This work has resolved the 19 th century anomalies and enabled us to confirm the locations of old quarries, to give affirmation to two previously unrecognised sites, and to show that the outcrop is still present. Thematic collection: This article is part of the Geology of Scotland collection available at: https://www.lyellcollection.org/topic/collections/geology-of-scotland
{"title":"Dr John Grant Malcolmson and a reconciliation of the Middle Devonian Lethen Bar and Lethen House fish bearing nodule localities","authors":"R. G. Davidson, N. H. Trewin, J. Armstrong, S. R. Waters","doi":"10.1144/sjg2023-011","DOIUrl":"https://doi.org/10.1144/sjg2023-011","url":null,"abstract":"The area known as Lethen Bar and Clune, SE of Nairn, Scotland, is a classic Middle Devonian locality which has yielded nodules or concretions, some of which contain fossil fishes with the highest quality of preservation. The locality was largely centred on farm limestone quarries situated around the perimeter of an isolated outlier of the main fishbed. It was first described in the 19 th century, although the upsurge in collecting fossil fishes only occurred some twelve years after the quarries were first mentioned in the scientific literature. Our knowledge of the provenance of the locality is based on very limited accounts, which have never been scientifically tested; these accounts also contain apparent anomalies that have never been adequately addressed. Based on these anomalies, the author of a paper published in 1983 proposed that the locality had been untraceable since the late 19 th century and that the outcrop was quarried out. In 2005, the present authors recorded the first scientifically detailed stratigraphical section of the fishbed, followed in 2021-2023 by detailed field surveys and by a re-appraisal of the literature. This work has resolved the 19 th century anomalies and enabled us to confirm the locations of old quarries, to give affirmation to two previously unrecognised sites, and to show that the outcrop is still present. Thematic collection: This article is part of the Geology of Scotland collection available at: https://www.lyellcollection.org/topic/collections/geology-of-scotland","PeriodicalId":49556,"journal":{"name":"Scottish Journal of Geology","volume":"331 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2023-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139220741","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Martín D. Ezcurra, Daniel Marke, Stig A. Walsh, Stephen L. Brusatte
The broadest diversification of early predatory dinosaurs is represented by the ‘coelophysoid-grade’ neotheropods, but their Hettangian–Sinemurian ( c. 191–201 Ma) record is scarce worldwide. More information is needed to shed light on the evolution of this dinosaur group after the end-Triassic mass extinction ( c. 201 Ma). Here we revisit the anatomy and phylogeny of one of these earliest Jurassic neotheropod specimens, an isolated partial tibia from the lower Sinemurian of the Isle of Skye (Scotland) that was previously identified as probably closely related to Liliensternus liliensterni and coelophysids. However, we found that the Skye specimen is positioned in the branch leading to Averostra (Ceratosauria + Tetanurae), in a polytomy with Sarcosaurus woodi from the late Hettangian–lower Sinemurian of central England and a clade composed of Tachiraptor admirabilis and Averostra. The morphology of the Skye specimen is congruent with that of referred specimens of Sarcosaurus woodi , but because it probably represents a skeletally immature specimen, we assign it to cf. Sarcosaurus woodi . The Skye specimen increases the number of averostran-line neotheropod specimens recorded in the Lower Jurassic of Europe and current evidence indicates that these forms, and not coelophysoids, were relatively common in this part of the world at that time. Supplementary material : Character list and dataset for phylogenetic analysis and 3D model of the tibia are available at https://doi.org/10.6084/m9.figshare.c.6863016 Thematic collection: This article is part of the Palaeontology of Scotland collection available at: https://www.lyellcollection.org/topic/collections/palaeontology-of-scotland
{"title":"A revision of the ‘coelophysoid-grade’ theropod specimen from the Lower Jurassic of the Isle of Skye (Scotland)","authors":"Martín D. Ezcurra, Daniel Marke, Stig A. Walsh, Stephen L. Brusatte","doi":"10.1144/sjg2023-012","DOIUrl":"https://doi.org/10.1144/sjg2023-012","url":null,"abstract":"The broadest diversification of early predatory dinosaurs is represented by the ‘coelophysoid-grade’ neotheropods, but their Hettangian–Sinemurian ( c. 191–201 Ma) record is scarce worldwide. More information is needed to shed light on the evolution of this dinosaur group after the end-Triassic mass extinction ( c. 201 Ma). Here we revisit the anatomy and phylogeny of one of these earliest Jurassic neotheropod specimens, an isolated partial tibia from the lower Sinemurian of the Isle of Skye (Scotland) that was previously identified as probably closely related to Liliensternus liliensterni and coelophysids. However, we found that the Skye specimen is positioned in the branch leading to Averostra (Ceratosauria + Tetanurae), in a polytomy with Sarcosaurus woodi from the late Hettangian–lower Sinemurian of central England and a clade composed of Tachiraptor admirabilis and Averostra. The morphology of the Skye specimen is congruent with that of referred specimens of Sarcosaurus woodi , but because it probably represents a skeletally immature specimen, we assign it to cf. Sarcosaurus woodi . The Skye specimen increases the number of averostran-line neotheropod specimens recorded in the Lower Jurassic of Europe and current evidence indicates that these forms, and not coelophysoids, were relatively common in this part of the world at that time. Supplementary material : Character list and dataset for phylogenetic analysis and 3D model of the tibia are available at https://doi.org/10.6084/m9.figshare.c.6863016 Thematic collection: This article is part of the Palaeontology of Scotland collection available at: https://www.lyellcollection.org/topic/collections/palaeontology-of-scotland","PeriodicalId":49556,"journal":{"name":"Scottish Journal of Geology","volume":" 68","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135191844","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
James O. Buckman, Simon J. Cuthbert, Paul G. Polson
The Arthropleurid trackway Diplichnites cuithensis has previously been described from Scotland from the Upper Carboniferous Serpukhovikan Limestone Coal Formation on the Isle of Arran, and the Lower Carboniferous Visean Pittenweem and Anstruther Formations on the East Fife coast. Here we describe a new west coast single trackway from the Serpukhovikan Limestone Coal Formation of Glasgow's, Linn Park. The trackway occurs associated with simple horizontal burrows assignable to Planolites? , vertical openings of Arenicolites, examples of Taenidium barretti (formerly Beaconites barretti ), and irregular large scale bioturbation or possibly rootlet casts. The trace fossils and sedimentary structures (including trough cross-bedding and flaser bedding) indicate a fluvial sandbar or plain environment, possibly of estuarine origin, locally colonized by plants. Diplichnites cuithensis (and other Diplichnites species) commonly occur associated with the burrow Taenidium barretti . The latter is known to have been widespread globally throughout the Carboniferous, and is a common component of fluviatile sequences within the Lower Carboniferous succession of NW Ireland. This suggests that previously undocumented older Scottish Carboniferous examples of both Diplichnites ichnospecies and Taenidium barretti may also be present, assuming that suitable environments persisted and are currently adequately exposed.
{"title":"Arthropleura trackway ( <i>Diplichnites cuithensis</i> ) from the Carboniferous, Serpukhovikan, Limestone Coal Formation, Clackmannan Group, Linn Park, Glasgow","authors":"James O. Buckman, Simon J. Cuthbert, Paul G. Polson","doi":"10.1144/sjg2021-019","DOIUrl":"https://doi.org/10.1144/sjg2021-019","url":null,"abstract":"The Arthropleurid trackway Diplichnites cuithensis has previously been described from Scotland from the Upper Carboniferous Serpukhovikan Limestone Coal Formation on the Isle of Arran, and the Lower Carboniferous Visean Pittenweem and Anstruther Formations on the East Fife coast. Here we describe a new west coast single trackway from the Serpukhovikan Limestone Coal Formation of Glasgow's, Linn Park. The trackway occurs associated with simple horizontal burrows assignable to Planolites? , vertical openings of Arenicolites, examples of Taenidium barretti (formerly Beaconites barretti ), and irregular large scale bioturbation or possibly rootlet casts. The trace fossils and sedimentary structures (including trough cross-bedding and flaser bedding) indicate a fluvial sandbar or plain environment, possibly of estuarine origin, locally colonized by plants. Diplichnites cuithensis (and other Diplichnites species) commonly occur associated with the burrow Taenidium barretti . The latter is known to have been widespread globally throughout the Carboniferous, and is a common component of fluviatile sequences within the Lower Carboniferous succession of NW Ireland. This suggests that previously undocumented older Scottish Carboniferous examples of both Diplichnites ichnospecies and Taenidium barretti may also be present, assuming that suitable environments persisted and are currently adequately exposed.","PeriodicalId":49556,"journal":{"name":"Scottish Journal of Geology","volume":"13 11","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135634698","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Only two lungfish have been recorded in the Scottish Coal Measures in the past one hundred and fifty years: Ctenodus and Sagenodus . Here we describe a suite of new lungfish specimens collected from sites in the Scottish Central Coalfield that represent a least four taxa: Sagenodus ; Conchopoma ; and two new forms Braccodus kerri gen. et sp. nov and Lanarkodus clarki gen. et sp. nov. These are part of an extensive vertebrate fauna recently discovered in colliery waste from mining the Upper and Lower Drumgray Coal. These coals lie within the Communis Chronozone and are of Langsettian age. The specimens are much smaller than those found previously in the Scottish Coal Measures and represent fish between 60 and 300 mm long. The basihyal tooth plates of Conchopoma are the first record of this genus in the Pennsylvanian of Europe. Lanarkodus clarki has a heterodont dentition not previously described from the Pennsylvanian. All the new material is preserved in thin, laminated shales, suggesting a small lake environment rather than the typical coal swamp. These new discoveries demonstrate that Pennsylvanian lungfish were more diverse than previously realised and add to growing evidence that the rate of lungfish evolution did not decline significantly after the Devonian, and remained high throughout the Carboniferous. Thematic collection: This article is part of the The Palaeontology of Scotland collection available at: https://www.lyellcollection.org/topic/collections/palaeontology-of-scotland
{"title":"Dipnoan diversity in the early Pennsylvanian of Scotland: new lungfish from the Lower Coal Measures of North Lanarkshire","authors":"Francis M. Elliott, T. Challands, T. Smithson","doi":"10.1144/sjg2023-006","DOIUrl":"https://doi.org/10.1144/sjg2023-006","url":null,"abstract":"\u0000 Only two lungfish have been recorded in the Scottish Coal Measures in the past one hundred and fifty years:\u0000 Ctenodus\u0000 and\u0000 Sagenodus\u0000 . Here we describe a suite of new lungfish specimens collected from sites in the Scottish Central Coalfield that represent a least four taxa:\u0000 Sagenodus\u0000 ;\u0000 Conchopoma\u0000 ; and two new forms\u0000 Braccodus kerri\u0000 gen. et sp. nov and\u0000 Lanarkodus clarki\u0000 gen. et sp. nov. These are part of an extensive vertebrate fauna recently discovered in colliery waste from mining the Upper and Lower Drumgray Coal. These coals lie within the\u0000 Communis\u0000 Chronozone and are of Langsettian age. The specimens are much smaller than those found previously in the Scottish Coal Measures and represent fish between 60 and 300 mm long. The basihyal tooth plates of\u0000 Conchopoma\u0000 are the first record of this genus in the Pennsylvanian of Europe.\u0000 Lanarkodus clarki\u0000 has a heterodont dentition not previously described from the Pennsylvanian. All the new material is preserved in thin, laminated shales, suggesting a small lake environment rather than the typical coal swamp. These new discoveries demonstrate that Pennsylvanian lungfish were more diverse than previously realised and add to growing evidence that the rate of lungfish evolution did not decline significantly after the Devonian, and remained high throughout the Carboniferous.\u0000 \u0000 \u0000 Thematic collection:\u0000 This article is part of the The Palaeontology of Scotland collection available at:\u0000 https://www.lyellcollection.org/topic/collections/palaeontology-of-scotland\u0000","PeriodicalId":49556,"journal":{"name":"Scottish Journal of Geology","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2023-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48803256","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A new species of Rhizodopsis is described from material recovered from several Carboniferous locations within the Midland Valley of Scotland. Individual dermal skull bones were obtained from derelict coal waste tips at Wester Bracco, North Lanarkshire from shales originally overlying the Drumgray Coal. Individual dermal skull bones are well preserved, allowing for detailed description and reconstructions of the skull roof and cheek. Rhizodopsis rankini sp. nov. is distinguished by the presence of a lobed opercular, a deeply embayed postparietal shield between the supratemporal and tabular bones, and enlarged lateral extrascapulars. Rhizodopsis is here included in the Megalichthyidae, and an emended diagnosis of the family is given. The composition of the genus Rhizodopsis is reviewed. Except for R hizodopsis hanbuchi, Rhizodopsis rankini and Rhizodopsis sauroides , all other species are based solely on scales. The validity of these scale-based species is reassessed and all but Rhizodopsis granulatus and Rhizodopsis mazonius are considered to be valid species. Thematic collection: This article is part of the The Palaeontology of Scotland collection available at: https://www.lyellcollection.org/topic/collections/palaeontology-of-scotland
{"title":"On a new species of\u0000 Rhizodopsis\u0000 from the Carboniferous of Scotland","authors":"Francis M. Elliott","doi":"10.1144/sjg2023-008","DOIUrl":"https://doi.org/10.1144/sjg2023-008","url":null,"abstract":"\u0000 A new species of\u0000 Rhizodopsis\u0000 is described from material recovered from several Carboniferous locations within the Midland Valley of Scotland. Individual dermal skull bones were obtained from derelict coal waste tips at Wester Bracco, North Lanarkshire from shales originally overlying the Drumgray Coal. Individual dermal skull bones are well preserved, allowing for detailed description and reconstructions of the skull roof and cheek.\u0000 Rhizodopsis rankini\u0000 sp. nov. is distinguished by the presence of a lobed opercular, a deeply embayed postparietal shield between the supratemporal and tabular bones, and enlarged lateral extrascapulars.\u0000 Rhizodopsis\u0000 is here included in the Megalichthyidae, and an emended diagnosis of the family is given. The composition of the genus\u0000 Rhizodopsis\u0000 is reviewed. Except for R\u0000 hizodopsis hanbuchi, Rhizodopsis rankini\u0000 and\u0000 Rhizodopsis sauroides\u0000 , all other species are based solely on scales. The validity of these scale-based species is reassessed and all but\u0000 Rhizodopsis granulatus\u0000 and\u0000 Rhizodopsis mazonius\u0000 are considered to be valid species.\u0000 \u0000 \u0000 Thematic collection:\u0000 This article is part of the The Palaeontology of Scotland collection available at:\u0000 https://www.lyellcollection.org/topic/collections/palaeontology-of-scotland\u0000","PeriodicalId":49556,"journal":{"name":"Scottish Journal of Geology","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2023-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44934731","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
J. Parnell, A. Boyce, J. Armstrong, A. Schito, D. Muirhead
Palaeoproterozoic marbles occur widely in North West Scotland. The isotopically heavy carbonate carbon (δ 13 C >3 ‰) in marbles that characterizes the worldwide Lomagundi-Jatuli Event (2.3 to 2.05 Ga) is recognized in each of the Laurentian Foreland, the Moine Nappe and the Sgurr Beag Nappe, over a 150 km transect across the Caledonian thrust belt. A light oxygen isotope composition distinguishes marbles which have been sheared and retrogressed by ingress of meteoric water, possibly during both Laxfordian and Caledonian orogenesis. The shearing of marbles also contributed to graphite formation (mean δ 13 C -7.2 ‰). Pyrite in the marbles contains isotopically heavy sulphur, typical of Palaeoproterozoic diagenetic sulphides precipitated from low-sulphate seawater. These data show that the ∼2 Ga marbles in Scotland are a high-quality archive of information on their depositional and post-depositional history. The data emphasize a continuum of a Palaeoproterozoic marble-graphite-sulphide bearing assemblage from Eastern Canada and Greenland through Scotland to Scandinavia.
{"title":"The stable isotope (C,O,S) record of Palaeoproterozoic marbles, Scotland","authors":"J. Parnell, A. Boyce, J. Armstrong, A. Schito, D. Muirhead","doi":"10.1144/sjg2023-009","DOIUrl":"https://doi.org/10.1144/sjg2023-009","url":null,"abstract":"\u0000 Palaeoproterozoic marbles occur widely in North West Scotland. The isotopically heavy carbonate carbon (δ\u0000 13\u0000 C >3 ‰) in marbles that characterizes the worldwide Lomagundi-Jatuli Event (2.3 to 2.05 Ga) is recognized in each of the Laurentian Foreland, the Moine Nappe and the Sgurr Beag Nappe, over a 150 km transect across the Caledonian thrust belt. A light oxygen isotope composition distinguishes marbles which have been sheared and retrogressed by ingress of meteoric water, possibly during both Laxfordian and Caledonian orogenesis. The shearing of marbles also contributed to graphite formation (mean δ\u0000 13\u0000 C -7.2 ‰). Pyrite in the marbles contains isotopically heavy sulphur, typical of Palaeoproterozoic diagenetic sulphides precipitated from low-sulphate seawater. These data show that the ∼2 Ga marbles in Scotland are a high-quality archive of information on their depositional and post-depositional history. The data emphasize a continuum of a Palaeoproterozoic marble-graphite-sulphide bearing assemblage from Eastern Canada and Greenland through Scotland to Scandinavia.\u0000","PeriodicalId":49556,"journal":{"name":"Scottish Journal of Geology","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2023-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47627872","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Fenitised rocks in Neoproterozoic country rocks adjacent to the Great Glen Fault, Scotland, contain calcite veins with mineral inclusions. The minerals include the rare earth vanadate wakefieldite, sulphur-rich monazite, scandium-rich ilmenite, and manganese oxides rich in barium and lead. Each of these phases is recorded in carbonatites elsewhere. An affinity with carbonatites is further suggested by the carbon isotope composition of the calcite veins, and anomalously high levels of manganese and strontium in the veins. These data add weight to a model in which Scotland northwest of the Great Glen Fault was affected by carbonatite-related fluids during the Caledonian Orogeny. Thematic collection: This article is part of the Early Career Research collection available at: https://www.lyellcollection.org/topic/collections/early-career-research
{"title":"Trace element minerals from carbonatite-related fluids, The Aird, Scotland","authors":"E. Heptinstall, J. Parnell, A. Boyce, J. Still","doi":"10.1144/sjg2021-015","DOIUrl":"https://doi.org/10.1144/sjg2021-015","url":null,"abstract":"Fenitised rocks in Neoproterozoic country rocks adjacent to the Great Glen Fault, Scotland, contain calcite veins with mineral inclusions. The minerals include the rare earth vanadate wakefieldite, sulphur-rich monazite, scandium-rich ilmenite, and manganese oxides rich in barium and lead. Each of these phases is recorded in carbonatites elsewhere. An affinity with carbonatites is further suggested by the carbon isotope composition of the calcite veins, and anomalously high levels of manganese and strontium in the veins. These data add weight to a model in which Scotland northwest of the Great Glen Fault was affected by carbonatite-related fluids during the Caledonian Orogeny.\u0000 \u0000 Thematic collection:\u0000 This article is part of the Early Career Research collection available at:\u0000 https://www.lyellcollection.org/topic/collections/early-career-research\u0000","PeriodicalId":49556,"journal":{"name":"Scottish Journal of Geology","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2023-06-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45757701","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Conglomerates are, commonly, only poorly fossiliferous at best. Yet beaches with common lithic clasts can be used to model the taphonomy of fossils in conglomeratic settings. Four beaches on the east coast of the Isle of Mull, Inner Hebrides, are clast-rich, with lithic pebbles, cobbles and boulders, but poor in shells, many of which are poorly preserved. There is ample evidence of shells being bored and encrusted, yet many or most of these were infested after death of the host. Of the ‘boring trinity’ – Caulostrepsis Clarke, Entobia Bronn and Gastrochaenolites Leymerie – so typical of the Trypanites Ichnofacies around Britain's coasts, only the last ichnogenus was not present, most likely due to the absence of suitable mobile substrates (such as limestone cobbles and oysters). Encrusters including Balanus , serpulids and spirorbids, show different patterns of preservation, probably due to multiple factors. Bored wood ( Apectoichnus ) was only found at one locality, which may be due to hydrodynamic sorting. Whelk shells show a range of patterns of breakage, most probably due to mechanical damage. But conglomerates commonly preserve fossil snails either complete or not at all. The results from these sites suggest that they represent an intermediate condition rarely preserved in the rock record.
一般来说，砾岩最多只能形成很差的化石。然而，具有共同岩屑碎屑的海滩可以用来模拟砾岩环境中的化石地貌学。内赫布里底群岛(Inner Hebrides)马尔岛(Isle of Mull)东海岸的四个海滩上，碎屑丰富，有鹅卵石、鹅卵石和巨石，但贝壳很少，其中许多保存得很差。有充分的证据表明，这些贝壳被钻穿和结壳，但其中许多或大部分在寄主死后被侵染。在“无聊的三位一体”——Caulostrepsis Clarke, Entobia Bronn和Gastrochaenolites Leymerie——是英国海岸周围典型的锥虫鱼相，只有最后一个鱼属没有出现，很可能是由于缺乏合适的可移动基质(如石灰石鹅卵石和牡蛎)。包括Balanus, serpulids和spirorbids在内的壳体呈现出不同的保存模式，可能是由于多种因素的影响。钻孔木(Apectoichnus)只在一个地方发现，这可能是由于水动力分选。海螺壳呈现出一系列破碎的模式，很可能是由于机械损伤。但是，砾岩通常保存完整的蜗牛化石，或者根本不保存。这些遗址的结果表明，它们代表了一种中间状态，很少在岩石记录中保存下来。
{"title":"Aspects of\u0000 Aktuo-Paläontologie\u0000 of the rocky beaches of the eastern Isle of Mull, UK","authors":"S. Donovan","doi":"10.1144/sjg2023-004","DOIUrl":"https://doi.org/10.1144/sjg2023-004","url":null,"abstract":"\u0000 Conglomerates are, commonly, only poorly fossiliferous at best. Yet beaches with common lithic clasts can be used to model the taphonomy of fossils in conglomeratic settings. Four beaches on the east coast of the Isle of Mull, Inner Hebrides, are clast-rich, with lithic pebbles, cobbles and boulders, but poor in shells, many of which are poorly preserved. There is ample evidence of shells being bored and encrusted, yet many or most of these were infested after death of the host. Of the ‘boring trinity’ –\u0000 Caulostrepsis\u0000 Clarke,\u0000 Entobia\u0000 Bronn and\u0000 Gastrochaenolites\u0000 Leymerie – so typical of the\u0000 Trypanites\u0000 Ichnofacies around Britain's coasts, only the last ichnogenus was not present, most likely due to the absence of suitable mobile substrates (such as limestone cobbles and oysters). Encrusters including\u0000 Balanus\u0000 , serpulids and spirorbids, show different patterns of preservation, probably due to multiple factors. Bored wood (\u0000 Apectoichnus\u0000 ) was only found at one locality, which may be due to hydrodynamic sorting. Whelk shells show a range of patterns of breakage, most probably due to mechanical damage. But conglomerates commonly preserve fossil snails either complete or not at all. The results from these sites suggest that they represent an intermediate condition rarely preserved in the rock record.\u0000","PeriodicalId":49556,"journal":{"name":"Scottish Journal of Geology","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2023-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45370309","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
N. Jagielska, T. Challands, Michael O'Sullivan, D. Ross, N. Fraser, M. Wilkinson, S. Brusatte
The transition between Early to Middle Jurassic was significant in pterosaur evolution, when these volant reptiles exploded in diversity alongside dinosaurs and other animals. It has long been thought, however, that pterosaurs did not develop large wingspans until after the Jurassic, a notion challenged by the recent discovery of Dearc sgiathanach in the Bathonian-aged Lealt Shale Formation of the Isle of Skye, Scotland, whose holotype specimen had an estimated wingspan greater than 2.5 meters. We here report the discovery of a new pterosaur specimen from the Lealt Shale Formation, comprising a tibiotarsus, metatarsal, pedal phalanges, and caudal vertebrae. The elongate tail vertebrae with ossified processes indicate the specimen is a non-pterodactyloid pterosaur, albeit its fragmentary nature makes it difficult to determine whether it belongs to a new taxon. Its metatarsal and caudal vertebrae are considerably larger than corresponding bones in the Dearc holotype, indicating that it belonged to an even larger individual, thus demonstrating that pterosaurs with broad wingspans were not anomalous in the Middle Jurassic. The growing Middle Jurassic pterosaur record of Scotland and England, although mostly represented by isolated and fragmentary fossils, reveals a high diversity of clades, long obscured by the lack of well-preserved skeletons.
{"title":"New postcranial remains from the Lealt Shale Formation of the Isle of Skye, Scotland, showcase hidden pterosaur diversity in the Middle Jurassic","authors":"N. Jagielska, T. Challands, Michael O'Sullivan, D. Ross, N. Fraser, M. Wilkinson, S. Brusatte","doi":"10.1144/sjg2023-001","DOIUrl":"https://doi.org/10.1144/sjg2023-001","url":null,"abstract":"\u0000 The transition between Early to Middle Jurassic was significant in pterosaur evolution, when these volant reptiles exploded in diversity alongside dinosaurs and other animals. It has long been thought, however, that pterosaurs did not develop large wingspans until after the Jurassic, a notion challenged by the recent discovery of\u0000 Dearc sgiathanach\u0000 in the Bathonian-aged Lealt Shale Formation of the Isle of Skye, Scotland, whose holotype specimen had an estimated wingspan greater than 2.5 meters. We here report the discovery of a new pterosaur specimen from the Lealt Shale Formation, comprising a tibiotarsus, metatarsal, pedal phalanges, and caudal vertebrae. The elongate tail vertebrae with ossified processes indicate the specimen is a non-pterodactyloid pterosaur, albeit its fragmentary nature makes it difficult to determine whether it belongs to a new taxon. Its metatarsal and caudal vertebrae are considerably larger than corresponding bones in the\u0000 Dearc\u0000 holotype, indicating that it belonged to an even larger individual, thus demonstrating that pterosaurs with broad wingspans were not anomalous in the Middle Jurassic. The growing Middle Jurassic pterosaur record of Scotland and England, although mostly represented by isolated and fragmentary fossils, reveals a high diversity of clades, long obscured by the lack of well-preserved skeletons.\u0000","PeriodicalId":49556,"journal":{"name":"Scottish Journal of Geology","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2023-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49619992","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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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