Scottish Journal of Geology最新文献_第3页

James Hutton. The Founder of Modern Geology, by Alan McKirdy. National Museums Scotland, Edinburgh. 2022 詹姆斯·赫顿。《现代地质学的创始人》，作者Alan McKirdy。苏格兰国家博物馆，爱丁堡。2022

IF 0.7 4区地球科学

Scottish Journal of Geology Pub Date : 2022-04-29 DOI: 10.1144/sjg2022-008

P. Stone

引用次数: 0

Temporal and spatial variations in calcium carbonate deposition in a mixed siliciclastic–carbonate deep marine system: the Ediacaran Deeside Limestone Formation, Aboyne, Scotland 石英-碳酸盐混合海洋体系中碳酸钙沉积的时空变化:埃迪卡拉纪Deeside石灰岩组，苏格兰Aboyne

IF 0.7 4区地球科学

Scottish Journal of Geology Pub Date : 2022-04-29 DOI: 10.1144/sjg2021-017

S. J. Drake, E. Gomez‐Rivas, R. Ickert, D. Macdonald

{"title":"Temporal and spatial variations in calcium carbonate deposition in a mixed siliciclastic–carbonate deep marine system: the Ediacaran Deeside Limestone Formation, Aboyne, Scotland","authors":"S. J. Drake, E. Gomez‐Rivas, R. Ickert, D. Macdonald","doi":"10.1144/sjg2021-017","DOIUrl":"https://doi.org/10.1144/sjg2021-017","url":null,"abstract":"The Deeside Limestone Formation (DLF), outcropping in western Aberdeenshire, comprises the eastern margin of a distinctive Upper Dalradian mixed siliciclastic–carbonate system of Ediacaran age which may be correlated southwestwards for more than 400 km to County Donegal in Ireland. A reconstructed stratigraphic column suggests three broad vertical sequences (S1–S3), each comprising a general upward proportionate increase in calcium carbonate with respect to quartz, locally capped by metalimestones (L1–L3). A simple explanation for this upward change lies in the differing physical response of the two heterolithic components under the same hydrodynamic process, with the heavier quartz grains preferentially enriching the bedload and the finer carbonate mud fraction, the suspended load. The three metalimestone intervals are observed only in central/eastern parts of the field area, suggesting a lateral facies variation. The predominance of calcareous–siliciclastic bed-scale compositional mixing within the DLF suggests sedimentation on the Dalradian shelf comprised contemporaneous mixing of the siliciclastic and carbonate fractions prior to subsequent re-mixing during transportation downslope into the deep water, punctuated by pulses of point-sourced siliciclastic input.","PeriodicalId":49556,"journal":{"name":"Scottish Journal of Geology","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2022-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47352825","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}

引用次数: 0

Mush ado about the Ratagain Complex, NW Scotland: insights into Caledonian granitic magmatism and emplacement from magnetic fabric analyses 苏格兰西北部Ratagain杂岩的混乱:从磁性结构分析中了解加里东花岗岩岩浆作用和侵位

IF 0.7 4区地球科学

Scottish Journal of Geology Pub Date : 2022-04-19 DOI: 10.1144/sjg2021-018

A. Lawrence, M. Maffione, C. Stevenson

{"title":"Mush ado about the Ratagain Complex, NW Scotland: insights into Caledonian granitic magmatism and emplacement from magnetic fabric analyses","authors":"A. Lawrence, M. Maffione, C. Stevenson","doi":"10.1144/sjg2021-018","DOIUrl":"https://doi.org/10.1144/sjg2021-018","url":null,"abstract":"The anisotropy of magnetic susceptibility (AMS) is used to reveal subtle mineral alignment fabrics in apparently isotropic crystalline lithologies, including granites. Such petrofabrics can be produced by emplacement-related magma flow or post-emplacement tectonic strain. However, discriminating between flow-related and tectonic fabrics using field observations alone may be challenging and is usually a broad and arbitrary interpretation. In this contribution, we employ a range of magnetic analyses to characterize the origin of the petrofabric in the c. 425 Ma Ratagain Complex, NW Scotland, a composite Late Caledonian granitic intrusion. Our detailed magnetic analyses reveal that whilst all intrusive units carry an ambient tectonic overprint, critically, this has not developed into an obvious tectonic fabric and contains a horizontal shortening component indicative of transpression. This appears at odds with the well-defined Silurian (Scandian phase) regional transtensional tectonic regime from c. 420–415 Ma onwards. Accordingly, we suggest that either the complex is younger than previously thought or that it existed as a crystal-mush close to the magmatic solidus for a protracted period after its initial emplacement. This study lays the foundations for much-needed further investigations into the detailed emplacement mechanisms, timescales and petrogenesis of individual granitic intrusions, to aid understanding of Late Caledonian tectonics. Supplementary material: Supplementary data to this article are available at https://doi.org/10.6084/m9.figshare.c.5941375 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":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2022-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48279393","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}

引用次数: 2

A regional explanation for Laxfordian tectonic evolution and its implications for the Lewisian terrane model 拉克斯福特构造演化的区域解释及其对刘易斯地体模式的启示

IF 0.7 4区地球科学

Scottish Journal of Geology Pub Date : 2022-03-18 DOI: 10.1144/sjg2021-020

G. Park

{"title":"A regional explanation for Laxfordian tectonic evolution and its implications for the Lewisian terrane model","authors":"G. Park","doi":"10.1144/sjg2021-020","DOIUrl":"https://doi.org/10.1144/sjg2021-020","url":null,"abstract":"The later Paleoproterozoic (Laxfordian) structural and metamorphic history of the Lewisian Complex can be explained by several major kinematic changes. At c. 1.9 Ga, the neighbouring Archean cratons of Rae, North Atlantic (NAC), Kola and Karelia were isolated from each other and subduction and accretion were active at their margins. At c. 1.85 Ga, during the ‘Early Laxfordian’, the Lewisian, then part of the Nagssugtoqidian orogenic belt, experienced NW–SE-directed tectonic movements attributed to east–west convergence between the Rae Craton and the NAC, probably prompted by collision with Baltica. At c. 1.7 Ga, during the ‘Late Laxfordian’, a major change to north–south convergence produced a combination of NW–SE-trending folds and NW–SE dextral shear zones. The kinematic system changed again after c. 1.6 Ga. The latter two changes may be attributable to the docking of further large cratons as the Nuna supercontinent was assembled. The Lewisian terrane model can be interpreted in terms of the relative movements between two major cratons, Rae and NAC. Sandwiched between them was a third, composed of material partly derived from a juvenile magmatic arc or arcs situated in oceanic crust. The Assynt terrane may be an isolated remnant of the upper-plate NAC, whereas most of the remaining Lewisian outcrop may consist of modified Rae material.","PeriodicalId":49556,"journal":{"name":"Scottish Journal of Geology","volume":"24 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2022-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"64034176","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}

引用次数: 1

Facies analysis of the Greywacke Conglomerate Formation, Glenbuck, Scotland 苏格兰Glenbuck地区Greywacke砾岩组相分析

IF 0.7 4区地球科学

Scottish Journal of Geology Pub Date : 2022-01-25 DOI: 10.1144/sjg2021-010

A. Mitten, A. Gough, A. Leslie, S. Clarke, M. Browne

{"title":"Facies analysis of the Greywacke Conglomerate Formation, Glenbuck, Scotland","authors":"A. Mitten, A. Gough, A. Leslie, S. Clarke, M. Browne","doi":"10.1144/sjg2021-010","DOIUrl":"https://doi.org/10.1144/sjg2021-010","url":null,"abstract":"The early Devonian Greywacke Conglomerate Formation of the Lanark Basin, southwestern Midland Valley of Scotland, has been exposed by a new road cut in the Glenbuck area, East Ayrshire, enabling a high-resolution sedimentological analysis of this unusually high-quality section. This study provides a facies analysis of the sedimentary rocks exposed in the Glenbuck area, and comparison with contemporaneous bedrock sections from across the Lanark Basin and adjacent Southern Upland High. Eleven lithofacies are identified, grouped into five associations: aggradational talus cone, progradational talus cone, debris flow lobe, fan surface aqueous-alluvial deposits, and gravel barform deposits. These comprise medial and proximal alluvial fan deposits, controlled by autogenic scour and avulsion along with general fan progradation. Contemporaneous sediments are present around Silurian inliers in the Lanark Basin and adjacent regions of the Southern Upland High. Whilst deposits in the Lanark Basin are genetically similar, contemporaneous deposits of the Southern Upland High preserve a distinctly more angular clast assemblage, indicating textural immaturity relative to those in the Lanark Basin.","PeriodicalId":49556,"journal":{"name":"Scottish Journal of Geology","volume":"58 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2022-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41961016","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}

引用次数: 1

Reply to discussion on ‘Deglaciation and neotectonics in SE Raasay, Scottish Inner Hebrides’, by Smith et al. 2021 (SJG, 57, 106–116) 对Smith等人关于“苏格兰内赫布里底群岛SE Raasay冰川消融与新构造”讨论的答复，2021 (SJG, 57, 106-116)

IF 0.7 4区地球科学

Scottish Journal of Geology Pub Date : 2021-10-22 DOI: 10.1144/sjg2021-014

David E. Smith, C. Firth, T. Mighall, P. Teasdale

引用次数: 0

Discussion on ‘Deglaciation and neotectonics in SE Raasay, Scottish Inner Hebrides’ by Smith et al. 2021 (SJG, 57, 106–116) Smith et al. 2021关于“苏格兰内赫布里底群岛SE Raasay冰川消融与新构造”的讨论(SJG, 57, 106-116)

IF 0.7 4区地球科学

Scottish Journal of Geology Pub Date : 2021-10-07 DOI: 10.1144/sjg2021-013

N. Morton

引用次数: 0

Radiocarbon dating of a composite multi-period debris cone stratigraphy in the Lochan na Lairige, Ben Lawers Ben Lawers Lochan na Lairige多期复合碎屑锥地层学的放射性碳年代测定