Mesorif Gabbros(External Rif, North Morocco): Ophiolitic Suture Witness or a “Newly Discovered” Manifestation of the Central Atlantic Magmatic Province?
Mesorif 斑粝岩(外部 Rif,诺思摩洛哥): Ophiolitic 缝术证人或中央大西洋 Magmatic 省的最新发现的表明?作者机构:UniversitéHassan II de CasablancaFacultédes Sciences Ben MsikDépartement de GéologieB.P.5366MaarifCasablancaMorocco UniversitéCergy-PontoiseDépartement Géosciences et Environnement 5GEG1 rue Descartes950000 Neuville/Oise CedexFrance UniversitéBlaise PascalLaboratoire Magmas et Volcans(UMR 6524)CNRS5 rue Kessler63038Clermont-FerrandFrance UniversitéAbdelmalek EssaadiFacultédes Sciences et Techniques de TangerBP 41990000 TangerMorocco
出 版 物:《Acta Geologica Sinica(English Edition)》 (地质学报(英文版))
年 卷 期:2020年第94卷第S01期
页 面:11-12页
核心收录:
学科分类:070902[理学-地球化学] 0709[理学-地质学] 070901[理学-矿物学、岩石学、矿床学] 07[理学]
主 题:external Rif Mesorif gabbro ophiolitic suture CAMP(the Central Atlantic Magmatic Province)
摘 要:The Rif Mountain located in Northern Morocco represents the westernmost extremity of the Peri-Mediterranean Alpine orogenic *** belt is classically subdivided into:1)Internal zones(or Internal Rif which is an allochthonous metamorphic domain known worldwide thanks to the presence of large peridotite outcrops);2)flysch zones(sediments corresponding to the original cover of the Maghrebian Tethys);and 3)External zones(or External Rif representing the North African margin remnants).The External Rif is itself subdivided into Prerif,Mesorif and Intrarif domains from the South to the North and is composed by Upper Triassic to Cenozoic sediments structured in a nappe *** rock intrusions were reported in this External Rif since the preliminary geological studies even if they were wrongly mapped asgranites.Later careful fieldwork and mapping studies specified nevertheless their gabbroic nature.A more recent petrological and geochemical study of a few outcrops of those gabbroic intrusions conducted the corresponding authors,encouraged by the presence of ultramafic rocks(Beni Malek serpentines)in the eastern part of the External Rif to consider those gabbros as oceanic and so,associated toan ophiolitic suture.Nevertheless,a recent and extended survey on the architecture and the rifting history of the Mesozoic margin of the Maghrebian Tethys focusing mainly on the Mesorif domain favor another *** detailed petrography of those mafic intrusions(mainly gabbros+dolerites and rarely extrusive rocks);their geochemical fingerprints and mainly their geochronological data(ages around 200 Ma based on U-Pb zircon LA-ICP dating)all together indicate clearly that those mafic intrusions are rather anewly discoveredmanifestation of the Central Atlantic Magmatic Province activityCAMPin the External Rif *** CAMP magmatism has been largely well described and characterized in all the other geological domains of Morocco(Anti-Atlas,High Atlas,Middle Atlas