scholarly journals Geomorphic response of a mountain gravel-bed river to an extreme flood in Aberdeenshire, Scotland

2020 ◽  
Vol 56 (2) ◽  
pp. 101-116
Author(s):  
Dina M. Fieman ◽  
Mikaël Attal ◽  
Stephen Addy
Keyword(s):  
Morphological Change ◽  
Early Career ◽  
Difference Threshold ◽  
Lateral Migration ◽  
Content Type ◽  
Link Type ◽  
Extreme Flood ◽  
Supplementary Material ◽  
Career Research ◽  
The Impact

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.4847946Thematic collection: This article is part of the Early Career Research collection available at: https://www.lyellcollection.org/cc/SJG-early-career-research

scholarly journals Environmental variability in response to abrupt climatic change during the Last Glacial–Interglacial Transition (16–8 cal ka BP): evidence from Mainland, Orkney

2019 ◽  
Vol 56 (1) ◽  
pp. 30-46 ◽  
Author(s):  
Ashley M. Abrook ◽  
Ian P. Matthews ◽  
Alice M. Milner ◽  
Ian Candy ◽  
Adrian P. Palmer ◽  
...  
Keyword(s):  
Early Career ◽  
Early Holocene ◽  
Content Type ◽  
Last Glacial ◽  
Principal Curve ◽  
Link Type ◽  
Supplementary Material ◽  
Career Research ◽  
The Last Glacial ◽  
Millennial Scale

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.4725269Thematic collection: This article is part of the ‘Early Career Research’ available at: https://www.lyellcollection.org/cc/SJG-early-career-research

scholarly journals First and most northern occurrence of a thalattosuchian crocodylomorph from the Jurassic of the Isle of Skye, Scotland

2020 ◽  
Vol 57 (1) ◽  
pp. sjg2020-013
Author(s):  
Kim J. Kean ◽  
Davide Foffa ◽  
Michela M. Johnson ◽  
Mark T. Young ◽  
Gert Greitens ◽  
...  
Keyword(s):  
Middle Jurassic ◽  
Dorsal Surface ◽  
Early Career ◽  
Content Type ◽  
Marine Deposits ◽  
Link Type ◽  
Research Collection ◽  
Career Research ◽  
Isle Of Skye

The Jurassic was a key interval for the evolution of dinosaurs, crocodylomorphs and many other vertebrate groups. In recent years, new vertebrate fossils have emerged from the Early–Middle Jurassic of the Isle of Skye, Scotland; however, much more is known about Skye's dinosaur fauna than its crocodylomorphs. Here we report new crocodylomorph material collected from Jurassic marine deposits at Prince Charlie's Cave on the NE coast of Skye. The specimen is a small cobble containing postcranial elements from an individual that is considerably larger in size than previous crocodylomorphs described from Skye. Based on features of the vertebrae and osteoderms, the specimen is assigned to Thalattosuchia, an extinct clade of semi-aquatic/pelagic crocodylomorphs. Specifically, the sub-circular and bean-shaped pit ornamentation on the dorsal surface of the osteoderms in alternating rows suggests affinities with the semi-aquatic lineage Teleosauroidea. Although the ornamentation pattern on the osteoderms is most similar to Macrospondylus (‘Steneosaurus’) bollensis, we conservatively assign the specimen to Teleosauroidea indeterminate. Regardless of its precise affinities and fragmentary nature, the specimen is the first thalattosuchian discovered in Scotland and is the most northerly reported Jurassic thalattosuchian globally, adding to our understanding of the palaeobiogeography and evolution of this group.Thematic collection: This article is part of the Early Career Research collection available at: https://www.lyellcollection.org/cc/SJG-early-career-research

Controls on subglacial bedrock erosion and morphology near Drumnadrochit, Scotland

2021 ◽  
Vol 57 (1) ◽  
pp. sjg2020-010
Author(s):  
M. B. Jonkman
Keyword(s):  
Field Work ◽  
Early Career ◽  
Content Type ◽  
Link Type ◽  
Bedrock Erosion ◽  
Research Collection ◽  
Career Research

Abrasion and plucking are important subglacial erosional processes that create different landforms. This study shows that properties of bedrock control subglacial erosion and bedrock morphology. Softer and less-jointed bedrock favours abrasion, while denser-jointed bedrock and harder bedrock do not. Field work for this study was carried out near Drumnadrochit in Inverness-shire, where the lithology, geology and morphology of rôches moutonnées and crag-and-tails were examined. In this area, the rôches moutonnées, which have an abraded stoss side, are only shaped out of a relatively soft, biotite-rich gneiss, with not much jointing. The crag-and-tails have more densely jointed stoss sides and are shaped out of serpentinite or a harder, more felsic gneiss. Foliation appears not to influence subglacial erosion, since the foliation in rôches moutonnées and crag-and-tails in the study area is similar.Thematic collection: This article is part of the Early Career Research collection available at: https://www.lyellcollection.org/cc/SJG-early-career-research

scholarly journals Teaching health education

2017 ◽  
Vol 117 (3) ◽  
pp. 323-340 ◽  
Author(s):  
Karen Pickett ◽  
Willeke Rietdijk ◽  
Jenny Byrne ◽  
Jonathan Shepherd ◽  
Paul Roderick ◽  
...  
Keyword(s):  
Health Promotion ◽  
Health Education ◽  
Life Experience ◽  
Education Programme ◽  
Practical Experience ◽  
Early Career ◽  
Health Issues ◽  
Structured Interviews ◽  
Content Type ◽  
The Impact

Purpose The purpose of this paper is to understand early career teachers’ perceptions of the impact of a pre-service health education programme on their health promotion practice in schools and the contextual factors that influence this. Design/methodology/approach Semi-structured interviews were conducted with 14 primary and secondary trainee and qualified teachers who had trained at a university in England. Data were analysed using thematic analysis. Findings The teachers found the training to be a useful introduction, particularly when it was relevant to their practice. They valued gaining practical skills at university, on placement and in school once qualified. They reported that witnessing pupils’ lives in school had increased their awareness that health education is important. Their personal qualities, life experience, the school’s ethos and competing pressures influenced their practice. Teachers considered that building relationships with colleagues, pupils and parents facilitated health promotion, and that health education needs to be relevant to pupils. Some teachers expressed that teaching about health could be a “minefield”. They also discussed whether schools or parents are responsible for educating pupils about health issues and the place of health promotion within education’s wider purpose. Originality/value Few studies have followed-up trainee teachers once they are in teaching posts to explore the longer-term perceived impact of pre-service health education training. The findings suggest that teachers’ development takes place via an interaction between training and practice, suggesting that training could particularly aim to provide teachers with a contextualised understanding of health issues and practical experience.

scholarly journals The university-to-work transition: responses of universities and organizations to the COVID-19 pandemic

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
William E. Donald ◽  
Melanie J. Ashleigh ◽  
Yehuda Baruch
Keyword(s):  
Organizational Behavior ◽  
Early Career ◽  
Career Services ◽  
Structured Interviews ◽  
Content Type ◽  
Work Transition ◽  
Global Labor Market ◽  
Career Literature ◽  
The University ◽  
The Impact

PurposeThe purpose of this study is to understand how universities and organizations have responded to the impact of the COVID-19 pandemic in terms of preparing university students and recent graduates to enter the global labor market, using the accounting, banking and finance sector as a case study. The two research questions are (1) How can university career services and organizations work individually and collaboratively to best develop early career talent following the COVID-19 pandemic? (2) What are the challenges that university career services and organizations face when working individually or collaboratively to develop early career talent following the COVID-19 pandemic?Design/methodology/approachThe data for thematic analysis comes from 36 semi-structured interviews with career advisors (CAs) (n = 19) and graduate recruiters (GRs) (n = 17).FindingsThis study offers some of the first findings on the impact of the COVID-19 pandemic, helping to ensure that organizational behavior and career theory literature reflect the dramatically changing landscape in the university-to-work transition.Originality/valueTheoretically, our contribution comes from applying a framework of the career construction theory (CTT) within the context of a career ecosystem to understand the views of the intermediary, meso-level actors, which, to date, have lacked representation within career literature. Practically, we provide an insightful bridge between universities and organizations, offering opportunities for greater collaboration, and enhanced outcomes for all stakeholders.

scholarly journals Evolution of a sand-rich submarine channel-lobe system and impact of mass-transport and transitional flow deposits on reservoir heterogeneity: Magnus Field, northern North Sea

2021 ◽  
pp. petgeo2020-095
Author(s):  
Michael J. Steventon ◽  
Christopher A-L. Jackson ◽  
Howard D. Johnson ◽  
David M. Hodgson ◽  
Sean Kelly ◽  
...  
Keyword(s):  
Mass Transport ◽  
North Sea ◽  
Fluid Pressure ◽  
Transitional Flow ◽  
Rock Properties ◽  
Sweep Efficiency ◽  
Content Type ◽  
Supplementary Material ◽  
Northern North Sea ◽  
The Impact

The geometry, distribution, and rock properties (i.e. porosity and permeability) of turbidite reservoirs, and the processes associated with turbidity current deposition, are relatively well known. However, less attention has been given to the equivalent properties resulting from laminar sediment gravity-flow deposition, with most research limited to cogenetic turbidite-debrites (i.e. transitional flow deposits) or subsurface studies that focus predominantly on seismic-scale mass-transport deposits (MTDs). Thus, we have a limited understanding of the ability of sub-seismic MTDs to act as hydraulic seals and their effect on hydrocarbon production, and/or carbon storage. We investigate the gap between seismically resolvable and sub-seismic MTDs, and transitional flow deposits on long-term reservoir performance in this analysis of a small (<10 km radius submarine fan system), Late Jurassic, sandstone-rich stacked turbidite reservoir (Magnus Field, northern North Sea). We use core, petrophysical logs, pore fluid pressure, quantitative evaluation of minerals by scanning electron microscopy (QEMSCAN), and 3D seismic-reflection datasets to quantify the type and distribution of sedimentary facies and rock properties. Our analysis is supported by a relatively long (c. 37 years) and well-documented production history. We recognise a range of sediment gravity deposits: (i) thick-/thin- bedded, structureless and structured turbidite sandstone, constituting the primary productive reservoir facies (c. porosity = 22%, permeability = 500 mD), (ii) a range of transitional flow deposits, and (iii) heterogeneous mud-rich sandstones interpreted as debrites (c. porosity = <10%, volume of clay = 35%, up to 18 m thick). Results from this study show that over the production timescale of the Magnus Field, debrites act as barriers, compartmentalising the reservoir into two parts (upper and lower reservoir), and transitional flow deposits act as baffles, impacting sweep efficiency during production. Prediction of the rock properties of laminar and transitional flow deposits, and their effect on reservoir distribution, has important implications for: (i) exploration play concepts, particularly in predicting the seal potential of MTDs, (ii) pore pressure prediction within turbidite reservoirs, and (iii) the impact of transitional flow deposits on reservoir quality and sweep efficiency.Supplementary material:https://doi.org/10.6084/m9.figshare.c.5313860

scholarly journals The naming of the Permian System

2021 ◽  
pp. jgs2021-037
Author(s):  
Michael J. Benton ◽  
Andrey G. Sennikov
Keyword(s):  
System Level ◽  
Naming Time ◽  
Content Type ◽  
Red Sandstone ◽  
Link Type ◽  
Permian System ◽  
Urgent Task ◽  
Great Leader ◽  
Supplementary Material ◽  
Access To Documents

The naming of the Permian by Roderick Murchison in 1841 is well known. This is partly because he ‘completed’ the stratigraphic column at system level, but also because of the exotic aspects of his extended fieldwork in remote parts of Russia and Murchison's reputed character. Here, we explore several debated and controversial aspects of this act, benefiting from access to documents and reports notably from Russian sources. Murchison or Sedgwick could have provided a name for the unnamed lower New Red Sandstone in 1835 based on British successions or those in Germany, so perhaps the Imperial aim of naming time from British geology was not the urgent task some have assumed. Murchison has been painted as arrogant and Imperialistic, which was doubtless true, but at the time many saw him as a great leader, even an attractive individual. Others suggest he succeeded because he stood on the shoulders of local geologists; however, his abilities at brilliant and rapid geological synthesis are undoubted. Two unexpected consequences of his work are that this arch conservative is revered in Russia as a hero of geological endeavours, and, for all his bombast, his ‘Permian’ was not widely accepted until 100 years after its naming.Supplementary material:https://doi.org/10.6084/m9.figshare.c.5412079

scholarly journals Dating protracted fault activities: microstructures, microchemistry and geochronology of the Vaikrita Thrust, Main Central Thrust zone, Garhwal Himalaya, NW India

2018 ◽  
Vol 481 (1) ◽  
pp. 127-146 ◽  
Author(s):  
Chiara Montemagni ◽  
Chiara Montomoli ◽  
Salvatore Iaccarino ◽  
Rodolfo Carosi ◽  
Arvind K. Jain ◽  
...  
Keyword(s):  
Electron Microprobe ◽  
Garhwal Himalaya ◽  
Main Central Thrust ◽  
Content Type ◽  
Mylonitic Foliation ◽  
Link Type ◽  
Thrust Zone ◽  
Supplementary Material ◽  
Structural Boundary

AbstractThe timing of shearing along the Vaikrita Thrust, the upper structural boundary of the Main Central Thrust Zone in the Garhwal Himalaya, was constrained by combined microstructural, microchemical and geochronological investigations. Three different biotite–muscovite growth and recrystallization episodes were observed: a relict mica-1; mica-2 along the main mylonitic foliation; and mica-3 in coronitic structures around garnet during its breakdown. Electron microprobe analyses of biotite showed chloritization and a bimodal composition of biotite-2 in one sample. Muscovite-2 and muscovite-3 differed in composition from each other. Biotite and muscovite 39Ar–40Ar age spectra from all samples showed both inter- and intra-sample discrepancies. Biotite step-ages ranged between 8.6 and 16 Ma and muscovite step-ages between 3.6 and 7.8 Ma. These ages cannot be interpreted as ‘cooling ages’ because samples from the same outcrop cooled simultaneously. Instead, the Ar systematics reflect sample-specific recrystallization markers. Intergrown impurities were diagnosed by the Ca/K ratios. The age data of biotite were interpreted as a mixture of true biotite-2 (9.00 ± 0.10 Ma) and two alteration products. The negative Cl/K–age correlation identified a Cl-poor muscovite-2 (>7 Ma) and a Cl-rich, post-deformational, coronitic muscovite-3 grown at ≤5.88 ± 0.03 Ma. The Vaikrita Thrust was active at least from 9 to 6 Ma at c. 600°C; its movement had ended by 6 Ma.Supplementary material: Thermometric and 39Ar–40Ar data are available at https://doi.org/10.6084/m9.figshare.c.4069076

Palaeolatitudinal distribution of the Ediacaran macrobiota

2021 ◽  
pp. jgs2021-030
Author(s):  
Catherine E. Boddy ◽  
Emily G. Mitchell ◽  
Andrew Merdith ◽  
Alexander G. Liu
Keyword(s):  
Taxonomic Composition ◽  
Supplementary Information ◽  
Cambrian Explosion ◽  
Content Type ◽  
Link Type ◽  
Environmental Perturbations ◽  
Significant Difference ◽  
Evolutionary Trajectories ◽  
Cambrian Radiation ◽  
Supplementary Material

Macrofossils of the late Ediacaran Period (c. 579–539 Ma) document diverse, complex multicellular eukaryotes, including early animals, prior to the Cambrian radiation of metazoan phyla. To investigate the relationships between environmental perturbations, biotic responses and early metazoan evolutionary trajectories, it is vital to distinguish between evolutionary and ecological controls on the global distribution of Ediacaran macrofossils. The contributions of temporal, palaeoenvironmental and lithological factors in shaping the observed variations in assemblage taxonomic composition between Ediacaran macrofossil sites are widely discussed, but the role of palaeogeography remains ambiguous. Here we investigate the influence of palaeolatitude on the spatial distribution of Ediacaran macrobiota through the late Ediacaran Period using two leading palaeogeographical reconstructions. We find that overall generic diversity was distributed across all palaeolatitudes. Among specific groups, the distributions of candidate ‘Bilateral’ and Frondomorph taxa exhibit weakly statistically significant and statistically significant differences between low and high palaeolatitudes within our favoured palaeogeographical reconstruction, respectively, whereas Algal, Tubular, Soft-bodied and Biomineralizing taxa show no significant difference. The recognition of statistically significant palaeolatitudinal differences in the distribution of certain morphogroups highlights the importance of considering palaeolatitudinal influences when interrogating trends in Ediacaran taxon distributions.Supplementary material: Supplementary information, data and code are available at https://doi.org/10.6084/m9.figshare.c.5488945Thematic collection: This article is part of the Advances in the Cambrian Explosion collection available at: https://www.lyellcollection.org/cc/advances-cambrian-explosion

Diamondiferous lamproites of Ingashi field, Siberian craton

2021 ◽  
pp. SP513-2020-274
Author(s):  
S. I. Kostrovitsky ◽  
D. A. Yakovlev ◽  
I. S. Sharygin ◽  
D. P. Gladkochub ◽  
T. V. Donskaya ◽  
...  
Keyword(s):  
Trace Element ◽  
Siberian Craton ◽  
Major Elements ◽  
Primary Sources ◽  
Content Type ◽  
Link Type ◽  
Ultramafic Lamprophyre ◽  
Dating Methods ◽  
Supplementary Material

AbstractIngashi lamproite dykes are the only known primary sources of diamond in the Irkutsk district (Russia) and the only non-kimberlitic one in the Siberian craton. Ingashi lamproite field placed in Urik-Iya graben within Prisayan uplift of Siberian craton. Phlogopite-olivine lamproites contain olivine, talc, phlogopite, serpentine, chlorite, olivine, garnet, chromite, orthopyroxene, clinopyroxene as well as Sr-F-apatite, monazite, zircon, armolcolite, priderite, potassium Mg-arfvedsonite, Mn-ilmenite, Nb-rutile, and diamond. The only one ultramafic lamprophyre dyke is composed mainly of serpentinized olivine and phlogopite in the talc-carbonate groundmass and similar (to Ingashi lamproites) accessory assemblage with the same major elements compositions. Trace element and Sr-Nd isotopic relationships of the Ingashi lamproites are similar to classic lamproites. Different dating methods have provided the ages of lamproites: 1481 Ma (Ar-Ar phlogopite), 1268 Ma (Rb-Sr whole rock) and 300 Ma (U-Pb zircon). Ingashi lamproite ages are controversial and require additional study. Calculated pressure of 3.5 GPamax for clinopyroxenes indicating that lamproite magma originated deeper than 100 km. Cr-in-garnet barometer (Grutter et al., 2006) shows a 3.7-4.3 GPamin and derivation of Ingashi lamproites deeper than 120 km depth. Based on the range of typical cratonic geotherms and presence of diamonds, the Ingashi lamproite magma originated at a depth greater than 155 km.Supplementary material at https://doi.org/10.6084/m9.figshare.c.5493128

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