Scottish Journal of Geology最新文献

{"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":null,"pages":null},"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}

{"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":null,"pages":null},"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}

{"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":null,"pages":null},"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}

{"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":null,"pages":null},"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}

{"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":null,"pages":null},"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":"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":null,"pages":null},"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}

{"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":null,"pages":null},"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}

{"title":"Digging deeper: The influence of historical mining on Glasgow's subsurface thermal state to inform geothermal research","authors":"S. Watson, R. Westaway, N. Burnside","doi":"10.1144/sjg2019-012","DOIUrl":"https://doi.org/10.1144/sjg2019-012","url":null,"abstract":"Studies of the former NE England coalfield in Tyneside demonstrated that heat flow perturbations in boreholes were due to the entrainment and lateral dispersion of heat from deeper in the subsurface through flooded mine workings. This work assesses the influence of historical mining on geothermal observations across Greater Glasgow. The regional heat flow for Glasgow is 60 mW m−2 and, after correction for palaeoclimate, is estimated as c. 80 mW m−2. An example of reduced heat flow above mine workings is observed at Hallside (c. 10 km SE of Glasgow), where the heat flow through a 352 m deep borehole is c. 14 mW m−2. Similarly, the heat flow across the 199 m deep GGC01 borehole in the Glasgow Geothermal Energy Research Field Site is c. 44 mW m−2. The differences between these values and the expected regional heat flow suggest a significant component of horizontal heat flow into surrounding flooded mine workings. This deduction also influences the quantification of deeper geothermal resources, as extrapolation of the temperature gradient above mine workings would underestimate the temperature at depth. Future projects should consider the influence of historical mining on heat flow when temperature datasets such as these are used in the design of geothermal developments. Supplementary material: Background information on the chronology of historical mining at each borehole location and a summary of groundwater flow in mine workings beneath Glasgow are available at https://doi.org/10.6084/m9.figshare.c.4681100 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":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1144/sjg2019-012","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43688995","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":"Book Review","authors":"C. Braithwaite","doi":"10.1144/sjg2019-021","DOIUrl":"https://doi.org/10.1144/sjg2019-021","url":null,"abstract":"Sedimentary structures were one of the features that drew this reviewer to the study of Sedimentology. They are, perhaps, the most eloquent among the many details observed in rocks, speaking to us about their conditions of deposition and the environment in which this occurred. If that seems a touch anthropomorphic, well, they talk to me! This is an impressive volume, well presented on good quality paper, and a credit to the publishers. It resembled a ‘Coffee-Table book’, but this is not a criticism, the use of this term is fully justified by countless high quality colour images and prolific line illustrations of the features discussed. Pick it up, these catch the eye, and encourage further investigation. The photographs leave no doubt about the identity of the structures and the diagrams explain, with some help from the text, how and why they form. Good illustrations are not a trivial issue, so often students asked to illustrate features appear to see something quite different! There is a brief introduction to each chapter, and each includes sections on study techniques, recommended field and laboratory experience, and references. There are two novel features. The authors commonly describe simple experiments that would allow the reader to observe the effects discussed for themselves. Unusually, the references that follow chapters are limited to the names and dates of the work, but each has a brief critique of what the article cited offers to the topic addressed. Traditional bibliographic references for all chapters appear at the end of the volume. There are ten chapters, varying in length according to the material they contain. An Introduction to the study of sedimentary structures (5 pp) discusses the origins, principles, and aims of the science of sedimentology and reading is recommended. The discussion follows the various philosophical views, and principles, that have shaped sedimentology in particular, Actualism, the Uniformitarianism promoted by Lyell, and the Catastrophism espoused by Cuvier, and we see how these shaped the ways in which we look at sedimentary rocks. From the outset, the authors adopt a personal approach, addressing the reader directly and encouraging methodical observation and analysis. The core of the book is represented by six chapters, on Bedding (14 pp), the Basic properties of fluids, flows and sediment (24 pp), Erosional structures (relating principally to turbidite deposits, 21 pp), Depositional structures in muds, mudstones and shales (6 pp), Depositional structures of sands and sandstones (71pp), and Depositional structures in gravels, conglomerates and breccias (26 pp). These describe the characteristics of flow, and how sediments move, and generate structures ranging from ripples to large scale cross bedding. These stretch across a range of environments, from subaerial fluvial and aeolian deposits, to shallow storm deposits, bars, channels and deltas, and deep-water turbidite fans. Although the account includes ","PeriodicalId":49556,"journal":{"name":"Scottish Journal of Geology","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2019-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44819415","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":"Low-carbon GeoEnergy resource options in the Midland Valley of Scotland, UK","authors":"Niklas Heinemann, Niklas Heinemann, Juan Alcalde, Gareth Johnson, Jennifer J. Roberts, A. McCay, M. G. Booth","doi":"10.1144/sjg2019-007","DOIUrl":"https://doi.org/10.1144/sjg2019-007","url":null,"abstract":"Scotland is committed to be a carbon-neutral society by 2040 and has achieved the important initial step of decarbonizing power production. However, more ambitious measures are required to fully decarbonize all of the electricity, transport and heating sectors. We explore the potential to use low-carbon GeoEnergy resources and bioenergy combined with Carbon Capture and Storage (BECCS) in the Midland Valley area to decarbonize the Scottish economy and society. The Midland Valley has a long history of geological resource extraction and, as a result, the geology of the region is well characterized. Geothermal energy and subsurface energy storage have the potential to be implemented. Some of them, such as gravity and heat storage, could re-use the redundant mining infrastructure to decrease investment costs. Hydrogen storage could be of particular interest as the Midland Valley offers the required caprock–reservoir assemblages. BECCS is also a promising option to reduce overall CO2 emissions by between 1.10 and 4.40 MtCO2 a−1. The Midland Valley has enough space to grow the necessary crops, but CO2 storage will most likely be implemented in North Sea saline aquifers. The studied aspects suggest that the Midland Valley represents a viable option in Scotland for the exploitation of the majority of low-carbon GeoEnergy resources. 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":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2019-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47071592","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}