Recent earthquakes involving complex multi-fault rupture have increased our appreciation of the variety of rupture geometries and fault interactions that occur within the short duration of coseismic slip. Geometrical complexities are intrinsically linked with spatially heterogeneous slip and stress drop distributions, and hence need incorporating into seismic hazard analysis. Studies of exhumed ancient fault zones facilitate investigation of rupture processes in the context of lithology and structure at seismogenic depths. In the Gairloch Shear Zone, NW Scotland, foliated amphibolites host pseudotachylytes that record rupture geometries of ancient low-magnitude (≤MW 3) seismicity. Pseudotachylyte faults are commonly foliation parallel, indicating exploitation of foliation planes as weak interfaces for seismic rupture. Discordance and complexity are introduced by fault segmentation, stepovers, branching and brecciated dilational volumes. Pseudotachylyte geometries indicate that slip nucleation initiated simultaneously across several parallel foliation planes with millimetre and centimetre separations, leading to progressive interaction and ultimately linkage of adjacent segments and branches within a single earthquake. Interacting with this structural control, a lithological influence of abundant low disequilibrium melting-point amphibole facilitated coseismic melting, with relatively high coseismic melt pressure encouraging transient dilational sites. These faults elucidate controls and processes that may upscale to large active fault zones hosting major earthquake activity. Supplementary material: Supplementary Figures 1 and 2, unannotated versions of field photographs displayed in Figures 4a and 5 respectively, are available at https://doi.org/10.6084/m9.figshare.c.4573256 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":"Rupture geometries in anisotropic amphibolite recorded by pseudotachylytes in the Gairloch Shear Zone, NW Scotland","authors":"L. Campbell, R. Phillips, R. Walcott, G. Lloyd","doi":"10.1144/sjg2019-003","DOIUrl":"https://doi.org/10.1144/sjg2019-003","url":null,"abstract":"Recent earthquakes involving complex multi-fault rupture have increased our appreciation of the variety of rupture geometries and fault interactions that occur within the short duration of coseismic slip. Geometrical complexities are intrinsically linked with spatially heterogeneous slip and stress drop distributions, and hence need incorporating into seismic hazard analysis. Studies of exhumed ancient fault zones facilitate investigation of rupture processes in the context of lithology and structure at seismogenic depths. In the Gairloch Shear Zone, NW Scotland, foliated amphibolites host pseudotachylytes that record rupture geometries of ancient low-magnitude (≤MW 3) seismicity. Pseudotachylyte faults are commonly foliation parallel, indicating exploitation of foliation planes as weak interfaces for seismic rupture. Discordance and complexity are introduced by fault segmentation, stepovers, branching and brecciated dilational volumes. Pseudotachylyte geometries indicate that slip nucleation initiated simultaneously across several parallel foliation planes with millimetre and centimetre separations, leading to progressive interaction and ultimately linkage of adjacent segments and branches within a single earthquake. Interacting with this structural control, a lithological influence of abundant low disequilibrium melting-point amphibole facilitated coseismic melting, with relatively high coseismic melt pressure encouraging transient dilational sites. These faults elucidate controls and processes that may upscale to large active fault zones hosting major earthquake activity. Supplementary material: Supplementary Figures 1 and 2, unannotated versions of field photographs displayed in Figures 4a and 5 respectively, are available at https://doi.org/10.6084/m9.figshare.c.4573256 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":"2019-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1144/sjg2019-003","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46315757","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}
F. Todd, C. McDermott, A. Harris, A. Bond, S. Gilfillan
In order to establish sustainable heat loading (heat removal and storage) in abandoned flooded mine workings it is important to understand the geomechanical impact of the cyclical heat loading caused by fluid injection and extraction. This is particularly important where significantly more thermal loading is planned than naturally occurs. A simple calculation shows that the sustainable geothermal heat flux from abandoned coal mines can provide less than a tenth of Scotland's annual domestic heating demand. Any heat removal greater than the natural heat flux will lead to heat mining unless heat storage options are also considered. As a first step, a steady-state, fully saturated, 2D coupled hydromechanical model of a generalized section of pillar-and-stall workings has been created. Mine water rebound was modelled by increasing the hydrostatic pressure sequentially, in line with monitored mine water-level data from Midlothian, Scotland. The modelled uplift to water-level rise ratio of 1.4 mm m−1 is of the same order of magnitude (1 mm m−1) as that observed through interferometric synthetic aperture radar (InSAR) data in the coalfield due to mine water rebound. The modelled magnitude of shear stress at the pillar corners, as a result of horizontal and vertical displacement, is shown to increase linearly with water level. Mine heat systems are expected to cause smaller changes in pressure than those modelled but the results provide initial implications on the potential geomechanical impacts of mine water heat schemes which abstract or inject water and heat into pillar-and-stall coal mine workings. 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":"Coupled hydraulic and mechanical model of surface uplift due to mine water rebound: implications for mine water heating and cooling schemes","authors":"F. Todd, C. McDermott, A. Harris, A. Bond, S. Gilfillan","doi":"10.1144/sjg2018-028","DOIUrl":"https://doi.org/10.1144/sjg2018-028","url":null,"abstract":"In order to establish sustainable heat loading (heat removal and storage) in abandoned flooded mine workings it is important to understand the geomechanical impact of the cyclical heat loading caused by fluid injection and extraction. This is particularly important where significantly more thermal loading is planned than naturally occurs. A simple calculation shows that the sustainable geothermal heat flux from abandoned coal mines can provide less than a tenth of Scotland's annual domestic heating demand. Any heat removal greater than the natural heat flux will lead to heat mining unless heat storage options are also considered. As a first step, a steady-state, fully saturated, 2D coupled hydromechanical model of a generalized section of pillar-and-stall workings has been created. Mine water rebound was modelled by increasing the hydrostatic pressure sequentially, in line with monitored mine water-level data from Midlothian, Scotland. The modelled uplift to water-level rise ratio of 1.4 mm m−1 is of the same order of magnitude (1 mm m−1) as that observed through interferometric synthetic aperture radar (InSAR) data in the coalfield due to mine water rebound. The modelled magnitude of shear stress at the pillar corners, as a result of horizontal and vertical displacement, is shown to increase linearly with water level. Mine heat systems are expected to cause smaller changes in pressure than those modelled but the results provide initial implications on the potential geomechanical impacts of mine water heat schemes which abstract or inject water and heat into pillar-and-stall coal mine workings. 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":"2019-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49351194","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}
We describe two large convergent multi-fluted glacigenic deposits in the NW Highlands, Scotland, and point out their resemblance to a number of landforms emerging from presently deglaciating areas of Greenland and Antarctica. We suggest that they all result from locally sourced sediment being deposited by local ice-flow, which was laterally confined by the margins of much larger adjacent glaciers or ice-streams. The NW Highlands features thus seem likely to be the result of processes active during the latter part of the Devensian Glaciation. One of these deposits, on the peninsula between Loch Broom and Little Loch Broom, is evidently sourced from the west-facing Coire Dearg of Beinn Ghobhlach, but was emplaced in a WNW direction rather than along the WSW fall-line. This suggests that the ice that emplaced it was confined by the margins of large glaciers then occupying the adjacent valleys of Loch Broom and Little Loch Broom. The second much larger and more prominent deposit, in Applecross, is composed of bouldery Torridonian sandstone till emplaced on to glacially scoured bedrock; the only feasible source location for this material is about 12 km distant, which requires that the deposit was carried by ice across the trough of Strath Maol Chalum and emplaced while active ice-streams confined it laterally to its present-day location. This, in turn, requires that ice lay in the Inner Sound between Applecross and Skye to an elevation 400–500 m above present-day sea-level. The Wester Ross Re-advance of 15–14 ka left a fragment of lateral moraine against the most easterly flute and buried the distal end of the flutes with hummocky moraine. We hypothesize that the fluted deposits reflect the locations of the ice-stream margins that constrained deposition of locally derived ice-transported sediment, rather than the flow-lines of the ice-stream itself.
{"title":"Very large convergent multi-fluted glacigenic deposits in the NW Highlands, Scotland","authors":"T. Davies, J. Warburton, J. Turnbull","doi":"10.1144/sjg2018-003","DOIUrl":"https://doi.org/10.1144/sjg2018-003","url":null,"abstract":"We describe two large convergent multi-fluted glacigenic deposits in the NW Highlands, Scotland, and point out their resemblance to a number of landforms emerging from presently deglaciating areas of Greenland and Antarctica. We suggest that they all result from locally sourced sediment being deposited by local ice-flow, which was laterally confined by the margins of much larger adjacent glaciers or ice-streams. The NW Highlands features thus seem likely to be the result of processes active during the latter part of the Devensian Glaciation. One of these deposits, on the peninsula between Loch Broom and Little Loch Broom, is evidently sourced from the west-facing Coire Dearg of Beinn Ghobhlach, but was emplaced in a WNW direction rather than along the WSW fall-line. This suggests that the ice that emplaced it was confined by the margins of large glaciers then occupying the adjacent valleys of Loch Broom and Little Loch Broom. The second much larger and more prominent deposit, in Applecross, is composed of bouldery Torridonian sandstone till emplaced on to glacially scoured bedrock; the only feasible source location for this material is about 12 km distant, which requires that the deposit was carried by ice across the trough of Strath Maol Chalum and emplaced while active ice-streams confined it laterally to its present-day location. This, in turn, requires that ice lay in the Inner Sound between Applecross and Skye to an elevation 400–500 m above present-day sea-level. The Wester Ross Re-advance of 15–14 ka left a fragment of lateral moraine against the most easterly flute and buried the distal end of the flutes with hummocky moraine. We hypothesize that the fluted deposits reflect the locations of the ice-stream margins that constrained deposition of locally derived ice-transported sediment, rather than the flow-lines of the ice-stream itself.","PeriodicalId":49556,"journal":{"name":"Scottish Journal of Geology","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2019-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1144/sjg2018-003","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47640215","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}
Late Devonian–Early Carboniferous rocks at the southern end of the Kintyre Peninsula closely resemble those of the Kinnesswood and Clyde Sandstone formations in more easterly portions of the Firth of Clyde. For example, a previously unrecognized thick marlstone with pedogenic calcretes is present in the Kinnesswood Formation at the south tip of the peninsula and, on the west coast, south of Machrihanish, a striking cliffed exposure includes massive phreatic calcretes developed from cross-bedded sandstones and red mudstones closely resembling those of the Clyde Sandstone on Great Cumbrae. A similar phreatic calcrete unit is present in the lower part of the Ballagan Formation in south Bute. The presence of vadose and phreatic calcrete provides valuable information concerning palaeoclimatic conditions in southwestern Scotland during the Devonian–Carboniferous transition. Overlying thick volcanic rocks are correlative with the Clyde Plateau Volcanic Formation. The sediments accumulated in the South Kintyre Basin on the west side of the Highland Boundary Fault (HBF). Formation of this basin, and the North East Arran and Cumbraes basins in the northeastern part of the Firth of Clyde, is interpreted as a response to development of a ‘locked zone’ in the HBF during an episode of sinistral faulting.
{"title":"The South Kintyre Basin: its role in the stratigraphical and structural evolution of the Firth of Clyde region during the Devonian–Carboniferous transition","authors":"G. M. Young, W. Caldwell","doi":"10.1144/sjg2019-001","DOIUrl":"https://doi.org/10.1144/sjg2019-001","url":null,"abstract":"Late Devonian–Early Carboniferous rocks at the southern end of the Kintyre Peninsula closely resemble those of the Kinnesswood and Clyde Sandstone formations in more easterly portions of the Firth of Clyde. For example, a previously unrecognized thick marlstone with pedogenic calcretes is present in the Kinnesswood Formation at the south tip of the peninsula and, on the west coast, south of Machrihanish, a striking cliffed exposure includes massive phreatic calcretes developed from cross-bedded sandstones and red mudstones closely resembling those of the Clyde Sandstone on Great Cumbrae. A similar phreatic calcrete unit is present in the lower part of the Ballagan Formation in south Bute. The presence of vadose and phreatic calcrete provides valuable information concerning palaeoclimatic conditions in southwestern Scotland during the Devonian–Carboniferous transition. Overlying thick volcanic rocks are correlative with the Clyde Plateau Volcanic Formation. The sediments accumulated in the South Kintyre Basin on the west side of the Highland Boundary Fault (HBF). Formation of this basin, and the North East Arran and Cumbraes basins in the northeastern part of the Firth of Clyde, is interpreted as a response to development of a ‘locked zone’ in the HBF during an episode of sinistral faulting.","PeriodicalId":49556,"journal":{"name":"Scottish Journal of Geology","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2019-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1144/sjg2019-001","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46352346","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 number of partial articulated specimens of Cheiracanthus peachi nov. sp. have been collected from the Mey Flagstone Formation and Rousay Flagstone Formation within the Orcadian Basin of northern Scotland. The new, robust-bodied species is mainly distinguished by the scale ornament of radiating grooves rather than ridges. Compared to other Cheiracanthus species in the Orcadian Basin, C. peachi nov. sp. has quite a short range making it a useful zone fossil. As well as describing the general morphology of the specimens, we have also described and figured SEM images of scales and histological sections of all elements, enabling identification of other, isolated remains. Of particular biological interest is the identification of relatively robust, tooth-like gill rakers. Finally, the species has also been identified from isolated scales in Belarus, where it appears earlier and has a longer stratigraphical range, implying the species evolved in the marine deposits of the east and migrated west into the Orcadian Basin via the river systems.
{"title":"A new cheiracanthid acanthodian from the Middle Devonian (Givetian) Orcadian Basin of Scotland and its biostratigraphic and biogeographical significance","authors":"J. D. Den Blaauwen, M. Newman, C. Burrow","doi":"10.1144/sjg2018-023","DOIUrl":"https://doi.org/10.1144/sjg2018-023","url":null,"abstract":"A number of partial articulated specimens of Cheiracanthus peachi nov. sp. have been collected from the Mey Flagstone Formation and Rousay Flagstone Formation within the Orcadian Basin of northern Scotland. The new, robust-bodied species is mainly distinguished by the scale ornament of radiating grooves rather than ridges. Compared to other Cheiracanthus species in the Orcadian Basin, C. peachi nov. sp. has quite a short range making it a useful zone fossil. As well as describing the general morphology of the specimens, we have also described and figured SEM images of scales and histological sections of all elements, enabling identification of other, isolated remains. Of particular biological interest is the identification of relatively robust, tooth-like gill rakers. Finally, the species has also been identified from isolated scales in Belarus, where it appears earlier and has a longer stratigraphical range, implying the species evolved in the marine deposits of the east and migrated west into the Orcadian Basin via the river systems.","PeriodicalId":49556,"journal":{"name":"Scottish Journal of Geology","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2019-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1144/sjg2018-023","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44557601","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}
S. Archer, R. Steel, D. Mellere, Stuart Blackwood, B. Cullen
The Hebridean Province of NW Scotland provides insight into the interaction between tectonics and shallow-marine and tidal strait depositional environments in the Sea of the Hebrides and Inner Hebrides basins. The study tests the influence of syn-depositional block tilting on gross thickness, sand to mud ratio and the distribution of shallow-marine facies in the resulting succession. New Middle Jurassic palaeogeographical maps and stratigraphic correlations are presented that integrate both outcrop and well data and illustrate the evolution of the deltaic sedimentary system in a broad, semi-regional context. Results show that distance from the sediment entry point and the syn-rift tectonic geomorphology were the critical controls on gross thickness, sand to mud ratios and facies types. The impact of relative sea-level change is hard to detect in locations proximal to the Scottish hinterland, where sediment supply was large relative to accommodation (Ss > Ac), but becomes more influential in distal locations where eustasy and tectonic subsidence convolved to increase the influence of accommodation over sediment supply (Ac > Ss). Supplementary material: An outcrop to well log correlation exercise is available at https://doi.org/10.6084/m9.figshare.c.4397858
{"title":"Response of Middle Jurassic shallow-marine environments to syn-depositional block tilting: Isles of Skye and Raasay, NW Scotland","authors":"S. Archer, R. Steel, D. Mellere, Stuart Blackwood, B. Cullen","doi":"10.1144/sjg2018-014","DOIUrl":"https://doi.org/10.1144/sjg2018-014","url":null,"abstract":"The Hebridean Province of NW Scotland provides insight into the interaction between tectonics and shallow-marine and tidal strait depositional environments in the Sea of the Hebrides and Inner Hebrides basins. The study tests the influence of syn-depositional block tilting on gross thickness, sand to mud ratio and the distribution of shallow-marine facies in the resulting succession. New Middle Jurassic palaeogeographical maps and stratigraphic correlations are presented that integrate both outcrop and well data and illustrate the evolution of the deltaic sedimentary system in a broad, semi-regional context. Results show that distance from the sediment entry point and the syn-rift tectonic geomorphology were the critical controls on gross thickness, sand to mud ratios and facies types. The impact of relative sea-level change is hard to detect in locations proximal to the Scottish hinterland, where sediment supply was large relative to accommodation (Ss > Ac), but becomes more influential in distal locations where eustasy and tectonic subsidence convolved to increase the influence of accommodation over sediment supply (Ac > Ss). Supplementary material: An outcrop to well log correlation exercise is available at https://doi.org/10.6084/m9.figshare.c.4397858","PeriodicalId":49556,"journal":{"name":"Scottish Journal of Geology","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2019-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1144/sjg2018-014","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42442622","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}
C. Young, Christophe Hendrickx, T. Challands, D. Foffa, D. Ross, I. Butler, S. Brusatte
The Middle Jurassic is a largely mysterious interval in dinosaur evolution, as few fossils of this age are known worldwide. In recent years, the Isle of Skye has yielded a substantial record of trackways, and a more limited inventory of body fossils, that indicate a diverse fauna of Middle Jurassic dinosaurs living in and around lagoons and deltas. Comparatively little is known about the predators in these faunas (particularly theropod dinosaurs), as their fossils are among the rarest discoveries. We here report two new isolated theropod teeth, from the Valtos Sandstone Formation and Lealt Shale Formation of Skye, which we visualized and measured using high-resolution x-ray computed microtomographic scanning (µCT) and identified via statistical and phylogenetic analyses of a large comparative dental dataset. We argue that these teeth most likely represent at least two theropod species – one small-bodied and the other large-bodied – which likely belonged to one or several clades of basal avetheropods (ceratosaurs, megalosauroids, or allosauroids). These groups, which were diversifying during the Middle Jurassic and would become dominant in the Late Jurassic, filled various niches in the food chain of Skye, probably both on land and in the lagoons. Supplementary material: Character lists, datasets, and measurements are available at https://doi.org/10.6084/m9.figshare.c.4452533
{"title":"New theropod dinosaur teeth from the Middle Jurassic of the Isle of Skye, Scotland","authors":"C. Young, Christophe Hendrickx, T. Challands, D. Foffa, D. Ross, I. Butler, S. Brusatte","doi":"10.1144/sjg2018-020","DOIUrl":"https://doi.org/10.1144/sjg2018-020","url":null,"abstract":"The Middle Jurassic is a largely mysterious interval in dinosaur evolution, as few fossils of this age are known worldwide. In recent years, the Isle of Skye has yielded a substantial record of trackways, and a more limited inventory of body fossils, that indicate a diverse fauna of Middle Jurassic dinosaurs living in and around lagoons and deltas. Comparatively little is known about the predators in these faunas (particularly theropod dinosaurs), as their fossils are among the rarest discoveries. We here report two new isolated theropod teeth, from the Valtos Sandstone Formation and Lealt Shale Formation of Skye, which we visualized and measured using high-resolution x-ray computed microtomographic scanning (µCT) and identified via statistical and phylogenetic analyses of a large comparative dental dataset. We argue that these teeth most likely represent at least two theropod species – one small-bodied and the other large-bodied – which likely belonged to one or several clades of basal avetheropods (ceratosaurs, megalosauroids, or allosauroids). These groups, which were diversifying during the Middle Jurassic and would become dominant in the Late Jurassic, filled various niches in the food chain of Skye, probably both on land and in the lagoons. Supplementary material: Character lists, datasets, and measurements are available at https://doi.org/10.6084/m9.figshare.c.4452533","PeriodicalId":49556,"journal":{"name":"Scottish Journal of Geology","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2019-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1144/sjg2018-020","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47365207","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}
Two errors have been identified in this paper. The correct text is noted below. page 104 2nd col line 18: ‘3.664 + 105 cal ka BP’ should be ‘3.664 + 0.105 cal ka BP’. page 111 2nd col line 2: ‘late Holocene’ should be corrected to ‘early Holocene
本文中发现了两个错误。正确的文本如下所示。第1042页第18行:“3.664+105 cal ka BP”应为“3.664+0.105 cal ka BP’。第1112页第2行:“全新世晚期”应更正为“全新世早期”
{"title":"Erratum for ‘Lateglacial to Holocene palaeoenvironmental change in the Muck Deep, offshore western Scotland’ Scottish Journal of Geology, 54, 99-114","authors":"R. Arosio, J. Howe","doi":"10.1144/SJG2018-025","DOIUrl":"https://doi.org/10.1144/SJG2018-025","url":null,"abstract":"Two errors have been identified in this paper. The correct text is noted below.\u0000\u0000page 104\u0000\u00002nd col line 18: ‘3.664 + 105 cal ka BP’ should be ‘3.664 + 0.105 cal ka BP’.\u0000\u0000page 111\u0000\u00002nd col line 2: ‘late Holocene’ should be corrected to ‘early Holocene","PeriodicalId":49556,"journal":{"name":"Scottish Journal of Geology","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2019-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1144/SJG2018-025","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42660121","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 Orkney granite complex dominates the outcropping basement on Orkney, Scotland. It comprises a grey and a pink variably foliated granite, and structurally younger pegmatites and aplites. Based on geochemical characteristics the granites are assigned to the Scottish high Ba–Sr granites. The granites are deformed by synmagmatic extensional east–west-trending mylonite zones. These are locally overprinted by similarly oriented extensional phyllonites and, in one case, by similarly oriented extensional faults. The grey and the pink granites are dated by zircon U–Pb CA-ID-TIMS to 431.93 ± 0.46 and 430.26 ± 0.92 Ma, respectively. An aplite cutting mylonitic granite and cut by phyllonite is dated to 428.50 ± 0.31 Ma. We interpret the shear zones to record north–south extension during emplacement and cooling of the granites, likely at a shallow crustal depth (4–12 km). The extension is best explained by a subsidiary pull-apart structure related to displacement on the Great Glen Fault. In this case, the Orkney granite complex dates transcurrent faulting to 432–429 Ma, coeval with the 431–429 Ma Moine Thrust. This indicates that strain partitioning and high Ba–Sr magmatism across the Scottish Highlands was an immediate response to attempted subduction of Avalonia beneath Laurentia during the Scandian collision. Supplementary material: Geochronological and geochemical data (Tables 1 and 2) as spreadsheets are available at https://doi.org/10.6084/m9.figshare.c.4304387
{"title":"Timing of strain partitioning and magmatism in the Scottish Scandian collision, evidence from the high Ba–Sr Orkney granite complex","authors":"A. Lundmark, L. Augland, Audun Dalene Bjerga","doi":"10.1144/sjg2018-001","DOIUrl":"https://doi.org/10.1144/sjg2018-001","url":null,"abstract":"The Orkney granite complex dominates the outcropping basement on Orkney, Scotland. It comprises a grey and a pink variably foliated granite, and structurally younger pegmatites and aplites. Based on geochemical characteristics the granites are assigned to the Scottish high Ba–Sr granites. The granites are deformed by synmagmatic extensional east–west-trending mylonite zones. These are locally overprinted by similarly oriented extensional phyllonites and, in one case, by similarly oriented extensional faults. The grey and the pink granites are dated by zircon U–Pb CA-ID-TIMS to 431.93 ± 0.46 and 430.26 ± 0.92 Ma, respectively. An aplite cutting mylonitic granite and cut by phyllonite is dated to 428.50 ± 0.31 Ma. We interpret the shear zones to record north–south extension during emplacement and cooling of the granites, likely at a shallow crustal depth (4–12 km). The extension is best explained by a subsidiary pull-apart structure related to displacement on the Great Glen Fault. In this case, the Orkney granite complex dates transcurrent faulting to 432–429 Ma, coeval with the 431–429 Ma Moine Thrust. This indicates that strain partitioning and high Ba–Sr magmatism across the Scottish Highlands was an immediate response to attempted subduction of Avalonia beneath Laurentia during the Scandian collision. Supplementary material: Geochronological and geochemical data (Tables 1 and 2) as spreadsheets are available at https://doi.org/10.6084/m9.figshare.c.4304387","PeriodicalId":49556,"journal":{"name":"Scottish Journal of Geology","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2018-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1144/sjg2018-001","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45931162","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}