意大利东北撒丁岛Variscan带卢拉副长岩碎屑锆石U-Pb年龄及地球化学特征:烃源岩和早古生代古地理意义

IF 1 4区 地球科学 Q4 GEOSCIENCES, MULTIDISCIPLINARY
G. Cruciani, M. Franceschelli, V. Caironi, G. Musumeci
{"title":"意大利东北撒丁岛Variscan带卢拉副长岩碎屑锆石U-Pb年龄及地球化学特征:烃源岩和早古生代古地理意义","authors":"G. Cruciani, M. Franceschelli, V. Caironi, G. Musumeci","doi":"10.3301/ijg.2019.24","DOIUrl":null,"url":null,"abstract":"Chemical analyses of garnet-bearing metasediments and EMP and U/Pb analyses of detrital zircons of the Lula paragneisses in the Axial Zone of the Variscan belt (NE Sardinia) give significant contribution to the reconstruction of the early Paleozoic evolution of the northern Gondwana margin. The youngest middle Ordovician (465 Ma) age of detrital zircons indicate a derivation from a fore- arc sedimentary basin along an early Paleozoic convergent margin, which collected sediments from nearby emerged lands consisting of early Paleozoic volcanic arcs and pre-Paleozoic sequences. The chemical composition of metasediments is characterized by negative Sr anomaly and depletion in heavy rare earth elements (HREE) and Y as compared to the upper crust. Normalized to chondrite values, the paragneiss shows a steep REE pattern with light-REE enrichment, negative Eu anomaly and flat heavy-REE pattern. All these features suggest a derivation form older active continental margins or island arcs. Detrital zircon ages cover a very large time span (3151 + 97 Ma to 465 + 8 Ma) and reveal a complex history of inheritance and recycling. The oldest ages obtained on relic cores and/or magmatic stages, mostly enriched in Hf (Zr / Hf ratios: 45-24) and devoid of Y, indicate a contribution from granitoid rocks of mainly crustal origin. The ages of detrital zircons highlight a derivation of the sedimentary supply from the Sahara craton and/or the Arabian-Numidian shield along the northeastern margin of Gondwana. This fit well with derivation of early Paleozoic metasedimentary formations in southern Sardinia and northern Apennine, pointing out a common origin and location of these sedimentary basins along the northern margin of Gondwana at the early Paleozoic. As regards the Variscan orogeny, the common middle Ordovician age of Lula paragneiss and nearby Lode orthogneiss highlight the role of Variscan tectonics in the assembly of different blocks of early-middle Paleozoic margin.","PeriodicalId":49317,"journal":{"name":"Italian Journal of Geosciences","volume":null,"pages":null},"PeriodicalIF":1.0000,"publicationDate":"2020-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"1","resultStr":"{\"title\":\"U-Pb ages on detrital zircons and geochemistry of Lula paragneiss from Variscan belt, NE Sardinia, Italy: implications for source rocks and early Paleozoic paleogeography\",\"authors\":\"G. Cruciani, M. Franceschelli, V. Caironi, G. Musumeci\",\"doi\":\"10.3301/ijg.2019.24\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"Chemical analyses of garnet-bearing metasediments and EMP and U/Pb analyses of detrital zircons of the Lula paragneisses in the Axial Zone of the Variscan belt (NE Sardinia) give significant contribution to the reconstruction of the early Paleozoic evolution of the northern Gondwana margin. The youngest middle Ordovician (465 Ma) age of detrital zircons indicate a derivation from a fore- arc sedimentary basin along an early Paleozoic convergent margin, which collected sediments from nearby emerged lands consisting of early Paleozoic volcanic arcs and pre-Paleozoic sequences. The chemical composition of metasediments is characterized by negative Sr anomaly and depletion in heavy rare earth elements (HREE) and Y as compared to the upper crust. Normalized to chondrite values, the paragneiss shows a steep REE pattern with light-REE enrichment, negative Eu anomaly and flat heavy-REE pattern. All these features suggest a derivation form older active continental margins or island arcs. Detrital zircon ages cover a very large time span (3151 + 97 Ma to 465 + 8 Ma) and reveal a complex history of inheritance and recycling. The oldest ages obtained on relic cores and/or magmatic stages, mostly enriched in Hf (Zr / Hf ratios: 45-24) and devoid of Y, indicate a contribution from granitoid rocks of mainly crustal origin. The ages of detrital zircons highlight a derivation of the sedimentary supply from the Sahara craton and/or the Arabian-Numidian shield along the northeastern margin of Gondwana. This fit well with derivation of early Paleozoic metasedimentary formations in southern Sardinia and northern Apennine, pointing out a common origin and location of these sedimentary basins along the northern margin of Gondwana at the early Paleozoic. As regards the Variscan orogeny, the common middle Ordovician age of Lula paragneiss and nearby Lode orthogneiss highlight the role of Variscan tectonics in the assembly of different blocks of early-middle Paleozoic margin.\",\"PeriodicalId\":49317,\"journal\":{\"name\":\"Italian Journal of Geosciences\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":1.0000,\"publicationDate\":\"2020-02-01\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"1\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Italian Journal of Geosciences\",\"FirstCategoryId\":\"89\",\"ListUrlMain\":\"https://doi.org/10.3301/ijg.2019.24\",\"RegionNum\":4,\"RegionCategory\":\"地球科学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q4\",\"JCRName\":\"GEOSCIENCES, MULTIDISCIPLINARY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Italian Journal of Geosciences","FirstCategoryId":"89","ListUrlMain":"https://doi.org/10.3301/ijg.2019.24","RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"GEOSCIENCES, MULTIDISCIPLINARY","Score":null,"Total":0}
引用次数: 1

摘要

对Variscan带(NE Sardinia)中轴带Lula paragneisses碎屑锆石的EMP和U/Pb分析,对重建冈瓦纳北缘早古生代演化具有重要意义。最年轻的中奥陶统(465 Ma)碎屑锆石年龄表明其来源于一个沿早古生代辐合边缘的弧前沉积盆地,该盆地收集了附近由早古生代火山弧和前古生代层序组成的出陆。与上地壳相比,沉积物的化学组成具有Sr负异常和重稀土元素(HREE)和Y亏缺的特征。与球粒陨石值归一化后,副辉岩呈现出轻稀土富集、负Eu异常和扁平重稀土模式的陡稀土模式。所有这些特征都表明它起源于更古老的活动大陆边缘或岛弧。碎屑锆石年龄跨度非常大(3151 + 97 Ma ~ 465 + 8 Ma),具有复杂的继承和再循环历史。在岩心和(或)岩浆阶段获得的最古老年龄,主要是富Hf (Zr / Hf比值:45-24)和缺乏Y,表明主要来自地壳起源的花岗岩类岩石。碎屑锆石的年龄强调了来自撒哈拉克拉通和/或冈瓦纳东北缘阿拉伯-努米迪亚盾的沉积供应来源。这与撒丁岛南部和亚平宁岛北部早古生代变质沉积地层的推导相吻合,指出了早古生代冈瓦纳北缘沉积盆地的共同起源和位置。在Variscan造山作用方面,Lula副长岩的共同中奥陶世和邻近的Lode正长岩突出了Variscan构造在早中古生代边缘不同块体组合中的作用。
本文章由计算机程序翻译,如有差异,请以英文原文为准。
U-Pb ages on detrital zircons and geochemistry of Lula paragneiss from Variscan belt, NE Sardinia, Italy: implications for source rocks and early Paleozoic paleogeography
Chemical analyses of garnet-bearing metasediments and EMP and U/Pb analyses of detrital zircons of the Lula paragneisses in the Axial Zone of the Variscan belt (NE Sardinia) give significant contribution to the reconstruction of the early Paleozoic evolution of the northern Gondwana margin. The youngest middle Ordovician (465 Ma) age of detrital zircons indicate a derivation from a fore- arc sedimentary basin along an early Paleozoic convergent margin, which collected sediments from nearby emerged lands consisting of early Paleozoic volcanic arcs and pre-Paleozoic sequences. The chemical composition of metasediments is characterized by negative Sr anomaly and depletion in heavy rare earth elements (HREE) and Y as compared to the upper crust. Normalized to chondrite values, the paragneiss shows a steep REE pattern with light-REE enrichment, negative Eu anomaly and flat heavy-REE pattern. All these features suggest a derivation form older active continental margins or island arcs. Detrital zircon ages cover a very large time span (3151 + 97 Ma to 465 + 8 Ma) and reveal a complex history of inheritance and recycling. The oldest ages obtained on relic cores and/or magmatic stages, mostly enriched in Hf (Zr / Hf ratios: 45-24) and devoid of Y, indicate a contribution from granitoid rocks of mainly crustal origin. The ages of detrital zircons highlight a derivation of the sedimentary supply from the Sahara craton and/or the Arabian-Numidian shield along the northeastern margin of Gondwana. This fit well with derivation of early Paleozoic metasedimentary formations in southern Sardinia and northern Apennine, pointing out a common origin and location of these sedimentary basins along the northern margin of Gondwana at the early Paleozoic. As regards the Variscan orogeny, the common middle Ordovician age of Lula paragneiss and nearby Lode orthogneiss highlight the role of Variscan tectonics in the assembly of different blocks of early-middle Paleozoic margin.
求助全文
通过发布文献求助,成功后即可免费获取论文全文。 去求助
来源期刊
Italian Journal of Geosciences
Italian Journal of Geosciences GEOSCIENCES, MULTIDISCIPLINARY-
CiteScore
2.90
自引率
11.10%
发文量
25
审稿时长
>12 weeks
期刊介绍: The Italian Journal of Geosciences (born from the merging of the Bollettino della Società Geologica Italiana and the Bollettino del Servizio Geologico d''Italia) provides an international outlet for the publication of high-quality original research contributions in the broad field of the geosciences. It publishes research papers, special short papers, review papers, discussion-and-replies for their rapid distribution to the international geosciences community. The journal is firstly intended to call attention to the Italian territory and the adjacent areas for the exceptional role they play in the understanding of geological processes, in the development of modern geology and the Earth sciences in general. The main focus of the journal is on the geology of Italy and the surrounding sedimentary basins and landmasses, and on their relationships with the Mediterranean geology and geodynamics. Nevertheless, manuscripts on process-oriented and regional studies concerning any other area of the World are also considered for publication. Papers on structural geology, stratigraphy, sedimentology, basin analysis, paleontology, ecosystems, paleoceanography, paleoclimatology, planetary sciences, geomorphology, volcanology, mineralogy, geochemistry, petrology, geophysics, geodynamics, hydrogeology, geohazards, marine and engineering geology, modelling of geological process, history of geology, the conservation of the geological heritage, and all related applied sciences are welcome.
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
确定
请完成安全验证×
copy
已复制链接
快去分享给好友吧!
我知道了
右上角分享
点击右上角分享
0
联系我们:info@booksci.cn Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术官方微信