Robert Jameson is generally remembered for championing Neptunist geology (originated by Abraham Werner) during its early nineteenth-century competition with the rival Plutonist theory (initiated by James Hutton). Hutton's ideas prevailed and Jameson's intellectual transition to Plutonism is documented in the surviving notes taken by students who attended his lectures at Edinburgh University: one early record is from 1809, a second record is from c. 1820 and four sets of notes are from the early 1830s. Of the latter four, two have not been previously considered from a geological perspective and prove to be the most revelatory of Jameson's conversion; notes compiled by the Royal Navy surgeon Robert McCormick are particularly comprehensive. Although Jameson attempted to maintain the essentials of Werner's theory for its well-ordered stratigraphy, he progressively adopted a Plutonist approach to more contentious issues such as the origin of granite, veining and mountain building. Jameson used Edinburgh's Salisbury Crags sill for field demonstrations and the students’ notes illustrate his changing views in terms of the origins of this classic geological feature. Of the students whose lecture notes survive, it is only McCormick for whom Jameson appears to have been a lasting geological influence.
{"title":"Robert Jameson's transition from Neptunism to Plutonism as reflected in his lectures at Edinburgh University, 1820–33","authors":"P. Stone","doi":"10.1144/sjg2019-031","DOIUrl":"https://doi.org/10.1144/sjg2019-031","url":null,"abstract":"Robert Jameson is generally remembered for championing Neptunist geology (originated by Abraham Werner) during its early nineteenth-century competition with the rival Plutonist theory (initiated by James Hutton). Hutton's ideas prevailed and Jameson's intellectual transition to Plutonism is documented in the surviving notes taken by students who attended his lectures at Edinburgh University: one early record is from 1809, a second record is from c. 1820 and four sets of notes are from the early 1830s. Of the latter four, two have not been previously considered from a geological perspective and prove to be the most revelatory of Jameson's conversion; notes compiled by the Royal Navy surgeon Robert McCormick are particularly comprehensive. Although Jameson attempted to maintain the essentials of Werner's theory for its well-ordered stratigraphy, he progressively adopted a Plutonist approach to more contentious issues such as the origin of granite, veining and mountain building. Jameson used Edinburgh's Salisbury Crags sill for field demonstrations and the students’ notes illustrate his changing views in terms of the origins of this classic geological feature. Of the students whose lecture notes survive, it is only McCormick for whom Jameson appears to have been a lasting geological influence.","PeriodicalId":49556,"journal":{"name":"Scottish Journal of Geology","volume":"56 1","pages":"85 - 99"},"PeriodicalIF":0.7,"publicationDate":"2020-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43897735","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 nominal species of crinoid, the diplobathrid camerates Diabolocrinus craigheadensis Ramsbottom and Diabolocrinus globularis (Nicholson and Etheridge), have been described from the Ordovician (Chatfieldian; Sandbian) Craighead Limestone Formation, Craighead Quarry, near Girvan, Ayrshire. In contrast, columnal morphotaxa are represented by over 20 taxa including those in open nomenclature. Two thecae from Craighead Quarry and referred to Diabolocrinus sp. or spp. preserve features of the stem facet that are similar to specimens referred to Oanducystis (col.) spp. from the same locality. These columnal morphotaxa are synonymized with Diabolocrinus and left in open nomenclature. However, Diabolocrinus is limited to Laurentia, whereas the remaining morphospecies of Oanducystis (col.) Stukalina are limited to Kazakhstan and Estonia.
{"title":"On Oanducystis (col.) Stukalina (Crinoidea) from the Craighead Limestone Formation, Girvan district, Ayrshire","authors":"S. Donovan, N. Clark","doi":"10.1144/sjg2019-022","DOIUrl":"https://doi.org/10.1144/sjg2019-022","url":null,"abstract":"Only two nominal species of crinoid, the diplobathrid camerates Diabolocrinus craigheadensis Ramsbottom and Diabolocrinus globularis (Nicholson and Etheridge), have been described from the Ordovician (Chatfieldian; Sandbian) Craighead Limestone Formation, Craighead Quarry, near Girvan, Ayrshire. In contrast, columnal morphotaxa are represented by over 20 taxa including those in open nomenclature. Two thecae from Craighead Quarry and referred to Diabolocrinus sp. or spp. preserve features of the stem facet that are similar to specimens referred to Oanducystis (col.) spp. from the same locality. These columnal morphotaxa are synonymized with Diabolocrinus and left in open nomenclature. However, Diabolocrinus is limited to Laurentia, whereas the remaining morphospecies of Oanducystis (col.) Stukalina are limited to Kazakhstan and Estonia.","PeriodicalId":49556,"journal":{"name":"Scottish Journal of Geology","volume":"63 27","pages":"81 - 84"},"PeriodicalIF":0.7,"publicationDate":"2020-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1144/sjg2019-022","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41281976","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}
The aetosaur Stagonolepis robertsoni was the first reptile to be named from the Late Triassic Lossiemouth Sandstone Formation of Morayshire. Its characteristic rectangular armour plates have been reported in isolation and in association with skeletal remains. Here we present for the first time a three-dimensional reconstruction of the armour plates around the tail in association with caudal vertebrae and a chevron, to give direct evidence of the body outline. The caudal vertebral column was surrounded by eight bony osteoderms, paired paramedian dorsal and ventral plates, and a pair of lateral osteoderms on right and left. The tail shape was subcircular, broader than high. The osteoderms overlap like roofing tiles, the posterior margin of each overlapping the osteoderm following behind. The success of these scans suggests that computed tomography scanning could reveal excellent detail of all the Elgin reptiles in the future. Supplementary material: Three-dimensional models of the two fossil specimens are available at: https://doi.org/10.6084/m9.figshare.c.4824183
{"title":"Three-dimensional tomographic study of dermal armour from the tail of the Triassic aetosaur Stagonolepis robertsoni","authors":"E. Keeble, M. Benton","doi":"10.1144/sjg2019-026","DOIUrl":"https://doi.org/10.1144/sjg2019-026","url":null,"abstract":"The aetosaur Stagonolepis robertsoni was the first reptile to be named from the Late Triassic Lossiemouth Sandstone Formation of Morayshire. Its characteristic rectangular armour plates have been reported in isolation and in association with skeletal remains. Here we present for the first time a three-dimensional reconstruction of the armour plates around the tail in association with caudal vertebrae and a chevron, to give direct evidence of the body outline. The caudal vertebral column was surrounded by eight bony osteoderms, paired paramedian dorsal and ventral plates, and a pair of lateral osteoderms on right and left. The tail shape was subcircular, broader than high. The osteoderms overlap like roofing tiles, the posterior margin of each overlapping the osteoderm following behind. The success of these scans suggests that computed tomography scanning could reveal excellent detail of all the Elgin reptiles in the future. Supplementary material: Three-dimensional models of the two fossil specimens are available at: https://doi.org/10.6084/m9.figshare.c.4824183","PeriodicalId":49556,"journal":{"name":"Scottish Journal of Geology","volume":"56 1","pages":"55 - 62"},"PeriodicalIF":0.7,"publicationDate":"2020-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1144/sjg2019-026","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48614809","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}
This study uses the 2015 ‘Storm Frank’ flood on the River Dee, Aberdeenshire, to assess the impact of extreme events on river dynamics. The Storm Frank flood (>200 year recurrence interval) caused significant local morphological change that was concentrated in the middle portion of the 140 km long river and overall net degradation that primarily occurred through lateral adjustment processes. Although the flood did not cause widespread change in channel planform, morphological change at the reach scale (<1 km) was significant. Bank scour resulted in channel expansion and lateral migration as well as widespread aggradation on existing gravel beds. The HEC-RAS and CAESAR–Lisflood models were used to determine the impact of morphological changes from the Storm Frank flood on a series of future hypothetical floods. The results show that inundation is highly influenced by the degree of morphological change for moderate floods, but not for high magnitude ones. In-channel scour and bank erosion can lead to an increase in channel capacity, thereby decreasing inundation. Conversely, where conveyance capacity is decreased by aggradation, flood risk inherently increases. The impact of these changes was great for a five-year return period flood, but minimal for a magnitude flood comparable to that of Storm Frank. Our modelling results also reveal that the inundation model is sensitive to the grain size and channel bed roughness input parameters, as these parameters impact flow discharge and flood hydraulics. Accurate determination of sediment parameters and degree of morphological change is therefore critical in flooding modelling and flood hazard management. Supplementary material: Peak discharge and rainfall during the 2015 Storm Frank storm, parameters used in the hydrological model CAESAR–Lisflood and sediment budget statistics of each DEM of difference threshold are available at: https://doi.org/10.6084/m9.figshare.c.4847946 Thematic collection: This article is part of the Early Career Research collection available at: https://www.lyellcollection.org/cc/SJG-early-career-research
{"title":"Geomorphic response of a mountain gravel-bed river to an extreme flood in Aberdeenshire, Scotland","authors":"Dina M. Fieman, Mikael Attal, S. Addy","doi":"10.1144/sjg2019-005","DOIUrl":"https://doi.org/10.1144/sjg2019-005","url":null,"abstract":"This study uses the 2015 ‘Storm Frank’ flood on the River Dee, Aberdeenshire, to assess the impact of extreme events on river dynamics. The Storm Frank flood (>200 year recurrence interval) caused significant local morphological change that was concentrated in the middle portion of the 140 km long river and overall net degradation that primarily occurred through lateral adjustment processes. Although the flood did not cause widespread change in channel planform, morphological change at the reach scale (<1 km) was significant. Bank scour resulted in channel expansion and lateral migration as well as widespread aggradation on existing gravel beds. The HEC-RAS and CAESAR–Lisflood models were used to determine the impact of morphological changes from the Storm Frank flood on a series of future hypothetical floods. The results show that inundation is highly influenced by the degree of morphological change for moderate floods, but not for high magnitude ones. In-channel scour and bank erosion can lead to an increase in channel capacity, thereby decreasing inundation. Conversely, where conveyance capacity is decreased by aggradation, flood risk inherently increases. The impact of these changes was great for a five-year return period flood, but minimal for a magnitude flood comparable to that of Storm Frank. Our modelling results also reveal that the inundation model is sensitive to the grain size and channel bed roughness input parameters, as these parameters impact flow discharge and flood hydraulics. Accurate determination of sediment parameters and degree of morphological change is therefore critical in flooding modelling and flood hazard management. Supplementary material: Peak discharge and rainfall during the 2015 Storm Frank storm, parameters used in the hydrological model CAESAR–Lisflood and sediment budget statistics of each DEM of difference threshold are available at: https://doi.org/10.6084/m9.figshare.c.4847946 Thematic collection: This article is part of the Early Career Research collection available at: https://www.lyellcollection.org/cc/SJG-early-career-research","PeriodicalId":49556,"journal":{"name":"Scottish Journal of Geology","volume":"56 1","pages":"101 - 116"},"PeriodicalIF":0.7,"publicationDate":"2020-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1144/sjg2019-005","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46298896","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}
B. Upton, L. Kirstein, N. Odling, J. Underhill, R. Ellam, N. Cayzer, Ben Clarke
Extensional tectonics and incipient rifting on the north side of the Iapetus suture were associated with eruption of (mainly) mildly alkaline olivine basalts. Initially in the Tournaisian (Southern Uplands Terrane), magmatic activity migrated northwards producing the Garleton Hills Volcanic Formation (GHVF) across an anomalous sector of the Southern Uplands. The latter was followed by resumption of volcanism in the Midland Valley Terrane, yielding the Arthur's Seat Volcanic Formation. Later larger-scale activity generated the Clyde Plateau Volcanic Formation (CPVF) and the Kintyre lavas on the Grampian Highlands Terrane. Comparable volcanic successions occur in Limerick, Ireland. This short-lived (c. 30 myr) phase was unique in the magmatic history of the Phanerozoic of the British Isles in which mildly alkaline basaltic magmatism locally led to trachytic differentiates. The Bangly Member of the GHVF represents the largest area occupied by such silicic rocks. The most widespread lavas and intrusions are silica-saturated/oversaturated trachytes for which new whole-rock and isotopic data are presented. Previously unrecognized ignimbrites are described. Sparse data from the fiamme suggest that the magma responsible for the repetitive ignimbrite eruptions was a highly fluid rhyolite. The Bangly Member probably represents the remains of a central-type volcano, the details of which are enigmatic.
{"title":"Silicic volcanism in the Scottish Lower Carboniferous; lavas, intrusions and ignimbrites of the Garleton Hills Volcanic Formation, SE Scotland","authors":"B. Upton, L. Kirstein, N. Odling, J. Underhill, R. Ellam, N. Cayzer, Ben Clarke","doi":"10.1144/sjg2019-008","DOIUrl":"https://doi.org/10.1144/sjg2019-008","url":null,"abstract":"Extensional tectonics and incipient rifting on the north side of the Iapetus suture were associated with eruption of (mainly) mildly alkaline olivine basalts. Initially in the Tournaisian (Southern Uplands Terrane), magmatic activity migrated northwards producing the Garleton Hills Volcanic Formation (GHVF) across an anomalous sector of the Southern Uplands. The latter was followed by resumption of volcanism in the Midland Valley Terrane, yielding the Arthur's Seat Volcanic Formation. Later larger-scale activity generated the Clyde Plateau Volcanic Formation (CPVF) and the Kintyre lavas on the Grampian Highlands Terrane. Comparable volcanic successions occur in Limerick, Ireland. This short-lived (c. 30 myr) phase was unique in the magmatic history of the Phanerozoic of the British Isles in which mildly alkaline basaltic magmatism locally led to trachytic differentiates. The Bangly Member of the GHVF represents the largest area occupied by such silicic rocks. The most widespread lavas and intrusions are silica-saturated/oversaturated trachytes for which new whole-rock and isotopic data are presented. Previously unrecognized ignimbrites are described. Sparse data from the fiamme suggest that the magma responsible for the repetitive ignimbrite eruptions was a highly fluid rhyolite. The Bangly Member probably represents the remains of a central-type volcano, the details of which are enigmatic.","PeriodicalId":49556,"journal":{"name":"Scottish Journal of Geology","volume":"56 1","pages":"63 - 79"},"PeriodicalIF":0.7,"publicationDate":"2020-01-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1144/sjg2019-008","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45124083","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. Hartley, B. Kurjanski, J. Pugsley, J. Armstrong
A dropstone horizon is described from lake deposits in a palaeo-valley from the c. 1000 Ma Diabaig Formation, Torridon Group, NW Scotland. Dropstones occur in wave-rippled, fine-grained sandstones and siltstones that contain desiccation and syneresis cracks indicative of fluctuating lake levels. Five locally derived dropstones occur at the same horizon over lateral distance of 250 m and display clear evidence of deflection and penetration of laminae at the base, with thinning, onlap and draping of laminae on to clast margins and tops. Mechanisms of dropstone formation are discussed, with ice-rafting considered the most likely explanation. It is suggested that rafting was promoted by cold winters at 35° S in the early Neoproterozoic, possibly in an upland setting. Interpretation of the dropstones as ice-rafted debris provides the first physical record of evidence for ice at the Earth's surface during the late Mesoproterozoic to early Neoproterozoic.
在苏格兰西北部Torridon组约1000 Ma Diabaig组古山谷的湖泊沉积物中描述了一个坠石层。水滴石出现在波浪起伏的细粒砂岩和粉砂岩中，其中含有指示湖泊水位波动的干燥和协同作用裂缝。在250米的横向距离上，在同一水平面上出现了5个局部衍生的坠石，并显示出底部层状岩的偏转和穿透的明显证据，层状岩在碎屑边缘和顶部上变薄、覆盖和覆盖。讨论了水滴石形成的机制，其中漂流被认为是最可能的解释。推测在新元古代早期，南纬35°的寒冷冬季促进了漂流，可能是在高原环境下。将坠石解释为冰筏碎片提供了中元古代晚期到新元古代早期地球表面冰的第一个物理记录。
{"title":"Ice-rafting in lakes in the early Neoproterozoic: dropstones in the Diabaig Formation, Torridon Group, NW Scotland","authors":"A. Hartley, B. Kurjanski, J. Pugsley, J. Armstrong","doi":"10.1144/sjg2019-017","DOIUrl":"https://doi.org/10.1144/sjg2019-017","url":null,"abstract":"A dropstone horizon is described from lake deposits in a palaeo-valley from the c. 1000 Ma Diabaig Formation, Torridon Group, NW Scotland. Dropstones occur in wave-rippled, fine-grained sandstones and siltstones that contain desiccation and syneresis cracks indicative of fluctuating lake levels. Five locally derived dropstones occur at the same horizon over lateral distance of 250 m and display clear evidence of deflection and penetration of laminae at the base, with thinning, onlap and draping of laminae on to clast margins and tops. Mechanisms of dropstone formation are discussed, with ice-rafting considered the most likely explanation. It is suggested that rafting was promoted by cold winters at 35° S in the early Neoproterozoic, possibly in an upland setting. Interpretation of the dropstones as ice-rafted debris provides the first physical record of evidence for ice at the Earth's surface during the late Mesoproterozoic to early Neoproterozoic.","PeriodicalId":49556,"journal":{"name":"Scottish Journal of Geology","volume":"56 1","pages":"47 - 53"},"PeriodicalIF":0.7,"publicationDate":"2020-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1144/sjg2019-017","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43436336","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}
In modern rivers, vegetation affects hydrological, geomorphological and sedimentological functioning, so extant fluvial systems can provide only partial analogues for those rivers that operated before the evolution of land plants. However, pre-vegetation rivers were the norm for the first 90% of Earth's history and so a better understanding of their sedimentary product can provide insights into both the fundamental underlying mechanisms of river behaviour and the ways in which fluvial processes operated on ancient Earth. In addition to a short review of the history of research into pre-vegetation alluvium, this paper presents a fieldwork-based case study of the later Proterozoic Torridon Group, which contains some of the most extensive and easily accessible exposures of pre-vegetation alluvium worldwide. Three alluvial architectural deposits have been recognized: (1) channel-bedform deposits (c. 80%); (2) barform deposits (c. 20%); and (3) out-of-channel deposits (≪1%). Channel-bedform deposits have erosional bases and most frequently stack vertically to form thick multistorey channel-bedform sequences. The preferential preservation of these deposits, which record the deepest parts of river channels, suggests that channel migration had a dominant control on preservation in the Torridon Group. Less frequently, channel-bedform deposits pass upwards into a genetically related barform deposit. Barform preservation in these instances is interpreted to be due to channel avulsion, which protected the barforms from reworking. Channel-bar thickness, measured from the basal erosional surface of a channel-bedform deposit to the top of its associated barform deposit, indicates minimum water depths of 1.7 to 8.0 m. Downstream-accreting barform deposits are most frequent, but lateral and upstream modes of accretion are also well represented. Dominant southeastward-palaeoflow directions imply that the Torridonian rivers were sourced from the Grenvillian Mountain Belt. The preserved architectural deposits and narrow dispersal of palaeocurrent data are explained by interpreting the Torridon Group as the alluvium of dominantly low-sinuosity rivers, with signatures recording autogenic fluvial adjustments. In the few rare instances where out-of-channel deposits are preserved, they contain fossil evidence for microbial mats, which prove that not all Proterozoic river systems were wholly abiotic. The overall characteristics of the Torridon alluvium, in terms of its ubiquitous highly tabular beds of sand-grade or coarser material, make it an archetypal example of pre-vegetation alluvium as known globally. Thematic collection: This article is part of the SJG Collection on Early-Career Research available at: https://www.lyellcollection.org/cc/SJG-early-career-research
{"title":"Physical and biological functioning in Proterozoic rivers: evidence from the archetypal pre-vegetation alluvium of the Torridon Group, NW Scotland","authors":"W. McMahon, N. Davies","doi":"10.1144/sjg2019-013","DOIUrl":"https://doi.org/10.1144/sjg2019-013","url":null,"abstract":"In modern rivers, vegetation affects hydrological, geomorphological and sedimentological functioning, so extant fluvial systems can provide only partial analogues for those rivers that operated before the evolution of land plants. However, pre-vegetation rivers were the norm for the first 90% of Earth's history and so a better understanding of their sedimentary product can provide insights into both the fundamental underlying mechanisms of river behaviour and the ways in which fluvial processes operated on ancient Earth. In addition to a short review of the history of research into pre-vegetation alluvium, this paper presents a fieldwork-based case study of the later Proterozoic Torridon Group, which contains some of the most extensive and easily accessible exposures of pre-vegetation alluvium worldwide. Three alluvial architectural deposits have been recognized: (1) channel-bedform deposits (c. 80%); (2) barform deposits (c. 20%); and (3) out-of-channel deposits (≪1%). Channel-bedform deposits have erosional bases and most frequently stack vertically to form thick multistorey channel-bedform sequences. The preferential preservation of these deposits, which record the deepest parts of river channels, suggests that channel migration had a dominant control on preservation in the Torridon Group. Less frequently, channel-bedform deposits pass upwards into a genetically related barform deposit. Barform preservation in these instances is interpreted to be due to channel avulsion, which protected the barforms from reworking. Channel-bar thickness, measured from the basal erosional surface of a channel-bedform deposit to the top of its associated barform deposit, indicates minimum water depths of 1.7 to 8.0 m. Downstream-accreting barform deposits are most frequent, but lateral and upstream modes of accretion are also well represented. Dominant southeastward-palaeoflow directions imply that the Torridonian rivers were sourced from the Grenvillian Mountain Belt. The preserved architectural deposits and narrow dispersal of palaeocurrent data are explained by interpreting the Torridon Group as the alluvium of dominantly low-sinuosity rivers, with signatures recording autogenic fluvial adjustments. In the few rare instances where out-of-channel deposits are preserved, they contain fossil evidence for microbial mats, which prove that not all Proterozoic river systems were wholly abiotic. The overall characteristics of the Torridon alluvium, in terms of its ubiquitous highly tabular beds of sand-grade or coarser material, make it an archetypal example of pre-vegetation alluvium as known globally. Thematic collection: This article is part of the SJG Collection on Early-Career Research available at: https://www.lyellcollection.org/cc/SJG-early-career-research","PeriodicalId":49556,"journal":{"name":"Scottish Journal of Geology","volume":"56 1","pages":"1 - 29"},"PeriodicalIF":0.7,"publicationDate":"2019-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1144/sjg2019-013","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44823736","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. Abrook, I. Matthews, A. Milner, I. Candy, A. Palmer, Rhys G. O. Timms
The Last Glacial–Interglacial Transition (LGIT) is a period of climatic complexity where millennial-scale climatic reorganization led to changes in ecosystems. Alongside millennial-scale changes, centennial-scale climatic events have been observed within records from Greenland and continental Europe. The effects of these abrupt events on landscapes and environments are difficult to discern at present. This, in part, relates to low temporal resolutions attained by many studies and the sensitivity of palaeoenvironmental proxies to abrupt change. We present a high-resolution palynological and charcoal study of Quoyloo Meadow, Orkney and use the Principal Curve statistical method to assist in revealing biostratigraphic change. The LGIT vegetation succession on Orkney is presented as open grassland and Empetrum heath during the Windermere Interstadial and early Holocene, and open grassland with Artemisia during the Loch Lomond Stadial. However, a further three phases of ecological change, characterized by expansions of open ground flora, are dated to 14.05–13.63, 10.94–10.8 and 10.2 cal ka BP. The timing of these changes is constrained by cryptotephra of known age. The paper concludes by comparing Quoyloo Meadow with Crudale Meadow, Orkney, and suggests that both Windermere Interstadial records are incomplete and that fire is an important landscape control during the early Holocene. Supplementary material: All raw data associated with this publication: raw pollen counts, charcoal data, Principal Curve and Rate of Change outputs and the age-model output are available at https://doi.org/10.6084/m9.figshare.c.4725269 Thematic collection: This article is part of the ‘Early Career Research’ available at: https://www.lyellcollection.org/cc/SJG-early-career-research
最后一次冰川-冰间过渡（LGIT）是一个气候复杂的时期，千年尺度的气候重组导致了生态系统的变化。除了千年尺度的变化外，在格陵兰岛和欧洲大陆的记录中还观察到了百年尺度的气候事件。这些突发事件对景观和环境的影响目前很难辨别。这在一定程度上与许多研究获得的低时间分辨率以及古环境指标对突变的敏感性有关。我们对奥克尼Quoyloo Meadow进行了高分辨率的孢粉学和木炭研究，并使用主曲线统计方法来帮助揭示生物地层的变化。奥克尼的LGIT植被演替在温德米尔季际和全新世早期表现为开阔草原和Empetrum荒原，在洛蒙德湖体育场表现为开阔草地和蒿属。然而，以开阔地植物群扩张为特征的生态变化的另外三个阶段分别为14.05-13.63、10.94-110.8和10.2 cal ka BP。这些变化的时间受到已知年龄的隐孢子虫的限制。本文通过将Quoyloo Meadow和奥克尼的Crudale Meadow进行比较得出结论，认为温德米尔的两个星际记录都是不完整的，火灾是全新世早期重要的景观控制因素。补充材料：与本出版物相关的所有原始数据：原始花粉计数、木炭数据、主曲线和变化率输出以及年龄模型输出可在https://doi.org/10.6084/m9.figshare.c.4725269专题集：本文是“早期职业研究”的一部分，可访问：https://www.lyellcollection.org/cc/SJG-early-career-research
{"title":"Environmental variability in response to abrupt climatic change during the Last Glacial–Interglacial Transition (16–8 cal ka BP): evidence from Mainland, Orkney","authors":"A. Abrook, I. Matthews, A. Milner, I. Candy, A. Palmer, Rhys G. O. Timms","doi":"10.1144/sjg2019-006","DOIUrl":"https://doi.org/10.1144/sjg2019-006","url":null,"abstract":"The Last Glacial–Interglacial Transition (LGIT) is a period of climatic complexity where millennial-scale climatic reorganization led to changes in ecosystems. Alongside millennial-scale changes, centennial-scale climatic events have been observed within records from Greenland and continental Europe. The effects of these abrupt events on landscapes and environments are difficult to discern at present. This, in part, relates to low temporal resolutions attained by many studies and the sensitivity of palaeoenvironmental proxies to abrupt change. We present a high-resolution palynological and charcoal study of Quoyloo Meadow, Orkney and use the Principal Curve statistical method to assist in revealing biostratigraphic change. The LGIT vegetation succession on Orkney is presented as open grassland and Empetrum heath during the Windermere Interstadial and early Holocene, and open grassland with Artemisia during the Loch Lomond Stadial. However, a further three phases of ecological change, characterized by expansions of open ground flora, are dated to 14.05–13.63, 10.94–10.8 and 10.2 cal ka BP. The timing of these changes is constrained by cryptotephra of known age. The paper concludes by comparing Quoyloo Meadow with Crudale Meadow, Orkney, and suggests that both Windermere Interstadial records are incomplete and that fire is an important landscape control during the early Holocene. Supplementary material: All raw data associated with this publication: raw pollen counts, charcoal data, Principal Curve and Rate of Change outputs and the age-model output are available at https://doi.org/10.6084/m9.figshare.c.4725269 Thematic collection: This article is part of the ‘Early Career Research’ available at: https://www.lyellcollection.org/cc/SJG-early-career-research","PeriodicalId":49556,"journal":{"name":"Scottish Journal of Geology","volume":"56 1","pages":"30 - 46"},"PeriodicalIF":0.7,"publicationDate":"2019-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47360734","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}
{"title":"Special Issue for Early Career Researchers: editorial","authors":"H. A. Stewart, M. Kirkbride","doi":"10.1144/sjg2019-029","DOIUrl":"https://doi.org/10.1144/sjg2019-029","url":null,"abstract":"Thematic collection: This article is part of the ‘Early Career Researchers’ available at: https://www.lyellcollection.org/cc/SJG-early-career-research","PeriodicalId":49556,"journal":{"name":"Scottish Journal of Geology","volume":"55 1","pages":"73 - 74"},"PeriodicalIF":0.7,"publicationDate":"2019-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44142931","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}
Large un-walled backfilled burrows of the Taenidium type are known from Paleozoic deltaic marine environments worldwide where they are often associated with Diplichnites trackways. The latter are generally attributed to arthropleurid myriapods and it may be that the burrows were also made by these animals. Here we describe a Taenidium burrow from the Limestone Coal Formation of the Isle of Arran, a formation that also hosts a well-known example of Diplichnites, supporting the association of the two types of trace fossil and extending their known co-occurrence upward into the Upper Carboniferous.
{"title":"A large Taenidium burrow from the Upper Carboniferous of Corrie, Isle of Arran, and remarks on the association of Taenidium burrows and Diplichnites trails","authors":"P. Pearson, Robert J. Gooday","doi":"10.1144/sjg2019-011","DOIUrl":"https://doi.org/10.1144/sjg2019-011","url":null,"abstract":"Large un-walled backfilled burrows of the Taenidium type are known from Paleozoic deltaic marine environments worldwide where they are often associated with Diplichnites trackways. The latter are generally attributed to arthropleurid myriapods and it may be that the burrows were also made by these animals. Here we describe a Taenidium burrow from the Limestone Coal Formation of the Isle of Arran, a formation that also hosts a well-known example of Diplichnites, supporting the association of the two types of trace fossil and extending their known co-occurrence upward into the Upper Carboniferous.","PeriodicalId":49556,"journal":{"name":"Scottish Journal of Geology","volume":"55 1","pages":"135 - 140"},"PeriodicalIF":0.7,"publicationDate":"2019-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1144/sjg2019-011","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49588018","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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