Comptes Rendus Geoscience最新文献_第8页

Holocene palaeogeographical reconstruction and relative sea-level changes in the southeastern part of the island of Samos (Greece) 希腊萨摩斯岛东南部全新世古地理重建与相对海平面变化

IF 1.4 4区地球科学

Comptes Rendus Geoscience Pub Date : 2019-08-01 DOI: 10.1016/j.crte.2019.09.001

Niki Evelpidou , Kosmas Pavlopoulos , Konstantinos Vouvalidis , George Syrides , Maria Triantaphyllou , Anna Karkani , Theodoros Paraschou

引用次数: 9

Structural evolution of the Téfidet trough (East Aïr, Niger) in relation with the West African Cretaceous and Paleogene rifting and compression episodes 尼日尔tsamfidet海槽(东Aïr)与西非白垩纪和古近纪裂陷和挤压期的构造演化

IF 1.4 4区地球科学

Comptes Rendus Geoscience Pub Date : 2019-06-01 DOI: 10.1016/j.crte.2018.11.009

Moussa Konaté, Yacouba Ahmed, Moussa Harouna

{"title":"Structural evolution of the Téfidet trough (East Aïr, Niger) in relation with the West African Cretaceous and Paleogene rifting and compression episodes","authors":"Moussa Konaté, Yacouba Ahmed, Moussa Harouna","doi":"10.1016/j.crte.2018.11.009","DOIUrl":"10.1016/j.crte.2018.11.009","url":null,"abstract":"<div>Located in northern Niger, the NW–SE Téfidet trough is the western branch of the Ténéré rift megasystem.Here we present a tectono-sedimentary analysis of the Téfidet trough, based on the combined use of satellite imagery, field observations and measures, and available literature. We use these data to analyse the sedimentary facies and the tectonic deformations (faults, folds, basins) in the Téfidet trough, and derive their relative chronology. Doing so, we characterize synrift and postrift deformations and their interactions with sedimentation.Altogether our analyses suggest that the Téfidet trough was affected from the Cretaceous to the Paleogene by three major tectonic periods.<ul><li>•The first period was a rifting stage with extension and transtension during the Albian–Aptian times. The mean extension was ∼N60° and dominantly produced NW–SE-trending normal faults, a few strike-slip faults locally associated with small folds with sigmoidal axis and small reverse faults, and progressive unconformities.</li><li>•the second period was also a rifting time, which prevailed during the Upper Cretaceous. The regime was marked by transtensional to extensional tectonics, under a ∼N130° shortening and a ∼N60° trending stretching. The end of this period saw the closure of the Téfidet trough.</li><li>•the third period was a postrift stage. It was characterized by a ∼N70° extensional to transtensional regime during the Oligocene–Pliocene. It mainly produced post-sedimentary extensional faults and fractures and alkaline volcanism. We eventually discuss these deformation phases in relation with the Cretaceous Gondwana breakup and its related rifting events in West and North Africa, and with the subsequent Africa–Europe collision.</li></ul></div>","PeriodicalId":50651,"journal":{"name":"Comptes Rendus Geoscience","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.crte.2018.11.009","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41983199","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

Tectono-metamorphic evolution of the European continental margin involved in the Alpine subduction: New insights from Alpine Corsica, France 参与阿尔卑斯俯冲的欧洲大陆边缘构造变质演化:来自法国阿尔卑斯科西嘉的新见解

IF 1.4 4区地球科学

Comptes Rendus Geoscience Pub Date : 2019-06-01 DOI: 10.1016/j.crte.2018.12.002

Maria Di Rosa , Chiara Frassi , Francesca Meneghini , Michele Marroni , Luca Pandolfi , Alberto De Giorgi

{"title":"Tectono-metamorphic evolution of the European continental margin involved in the Alpine subduction: New insights from Alpine Corsica, France","authors":"Maria Di Rosa , Chiara Frassi , Francesca Meneghini , Michele Marroni , Luca Pandolfi , Alberto De Giorgi","doi":"10.1016/j.crte.2018.12.002","DOIUrl":"10.1016/j.crte.2018.12.002","url":null,"abstract":"<div>In Corsica, continental units (the Lower Units) affected by high-pressure metamorphism represent the remains of the European margin deformed during the Alpine orogeny. In order to document how Alpine deformation and metamorphism changed along the European margin involved in the Alpine subduction, we selected three key areas: the Corte, Cima Pedani, and Ghisoni transects. The three transects show a broadly similar lithostratigraphy. They are characterized by a Variscan basement intruded by Permo-Carboniferous metagranitoids, and by a sedimentary cover including Mesozoic carbonates and middle to late Eocene breccias and sandstones. The three transects recorded a similar deformation history with three deformation phases. Thermo-baric estimations, instead, reveal that each unit was exhumed along an independent retrograde path within the orogenic Alpine wedge. In particular, the lowest units of the Lower Units stack were exhumed along an isothermal path, whereas those located at upper structural levels experienced progressive heating.</div>","PeriodicalId":50651,"journal":{"name":"Comptes Rendus Geoscience","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.crte.2018.12.002","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48601252","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 10

Editorial board ENG 编辑委员会ENG

IF 1.4 4区地球科学

Comptes Rendus Geoscience Pub Date : 2019-06-01 DOI: 10.1016/S1631-0713(19)30083-5

引用次数: 0

Morphometric analysis of the drainage network of Samos Island (northern Aegean Sea): Insights into tectonic control and flood hazards 爱琴海北部萨摩斯岛水系的形态计量学分析:构造控制和洪水灾害的启示

IF 1.4 4区地球科学

Comptes Rendus Geoscience Pub Date : 2019-06-01 DOI: 10.1016/j.crte.2019.03.001

Nikos Charizopoulos , Panagiotis Mourtzios , Thomas Psilovikos , Aris Psilovikos , Lina Karamoutsou

引用次数: 18

Variscan stress regime rotation: Insights from the analysis of kink folds in the northern margin of the Bohemian Massif, South Poland 华力西应力状态旋转：对波兰南部波希米亚地块北缘扭结褶皱的分析

IF 1.4 4区地球科学

Comptes Rendus Geoscience Pub Date : 2019-06-01 DOI: 10.1016/j.crte.2019.04.003

Jerzy Żaba, Krzysztof Gaidzik

{"title":"Variscan stress regime rotation: Insights from the analysis of kink folds in the northern margin of the Bohemian Massif, South Poland","authors":"Jerzy Żaba, Krzysztof Gaidzik","doi":"10.1016/j.crte.2019.04.003","DOIUrl":"10.1016/j.crte.2019.04.003","url":null,"abstract":"<div>We aimed to determine variations in stress regimes during the youngest Variscan deformations in the northern part of the Bohemian Massif. For this purpose, we calculated the orientation of the principal stress and strain axes for kink folds observed in the metamorphic envelope of the Karkonosze Granite, using two methods: 1) the traditional method, incorporating structural diagrams (for conjugate kink folds only), and 2) butterfly diagram analysis. The use of both methods enabled us to determine the stress regime, based not only on conjugate but also on monoclinal kink bands. The obtained results prove that butterfly diagram analysis, when applied to monoclinal kink folds, yields reliable results, especially when calibrated using the internal friction angle (Ф) calculated for the conjugate structures.We identified two generations of kink folds: 1) an older one, developed under sublatitudinal shortening and most probably related to the Early Carboniferous terminal stages of the northwest-directed thrusting of the metamorphic units, and 2) a younger one; produced by north-south Variscan Carboniferous compression, and the emplacement and subsequent doming of the Karkonosze Granite. This is the first study on brittle-ductile structures observed commonly in the metamorphic units of the Bohemian Massif, showing their relation to the granitoid intrusion and complementing the tectonic models that usually omit kink folds.</div>","PeriodicalId":50651,"journal":{"name":"Comptes Rendus Geoscience","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.crte.2019.04.003","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44897854","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Petrogenesis and tectonic significance of mafic-ultramafic rocks from southwestern Yunnan, China 滇西南镁铁质-超镁铁质岩石的成因及构造意义

IF 1.4 4区地球科学

Comptes Rendus Geoscience Pub Date : 2019-06-01 DOI: 10.1016/j.crte.2019.04.004

Qing Shi, Nianqiao Fang

引用次数: 2

Page de Sommaire Page de Sommaire

IF 1.4 4区地球科学

Comptes Rendus Geoscience Pub Date : 2019-06-01 DOI: 10.1016/S1631-0713(19)30086-0

引用次数: 0

Progradation and retrogradation of the Medjerda delta during the 20th century (Tunisia, western Mediterranean) 20世纪Medjerda三角洲的退化与发展(西地中海突尼斯)

IF 1.4 4区地球科学

Comptes Rendus Geoscience Pub Date : 2019-04-01 DOI: 10.1016/j.crte.2018.10.004

Thouraya Ben Moussa , Oula Amrouni , Abderraouf Hzami , Laurent Dezileau , Gil Mahé , Saâdi Abdeljaouad

{"title":"Progradation and retrogradation of the Medjerda delta during the 20th century (Tunisia, western Mediterranean)","authors":"Thouraya Ben Moussa , Oula Amrouni , Abderraouf Hzami , Laurent Dezileau , Gil Mahé , Saâdi Abdeljaouad","doi":"10.1016/j.crte.2018.10.004","DOIUrl":"10.1016/j.crte.2018.10.004","url":null,"abstract":"<div>The aim of this study is the reconstitution of the recent morpho-sedimentary evolution of the Medjerda River delta. We examine the spatio-temporal evolution of the Medjerda shoreline between 1936 and 2016 using satellite images, complemented by sedimentological and geochemical analyses and 210Pbex and 137Cs radiometric data. The general tendency of the shoreline evolution shows an increasing progradation (300 ± 12 m) between 1936 and 2016. Yet the mesoscale Net Shoreline Movement position (NSM) and the End Point Rate (EPR) reveal an erosion pattern estimated to be −20 m ± 0.15 m/yr during the period 1988–1999.The sedimentological analyses reveal four main lithostratigraphic units. The fine sand substratum layer (Md = 0.08 mm) decreases toward clay and silt facies (Md < 0.063 mm), rich in continental plant debris. The geochemical results reveal gradual incoming of the terrigenous component instead of marine deposits. The 137Cs/210Pbex radiometric dating confirms the functioning of the new river flow by the 1950s with the highest sedimentation rate being 3.3 cm/yr. Our results show that the Sidi-Salem dam impoundment (1981) led to a dramatic reduction of sediment discharge, a decrease of the grain size with nearly no more sand reaching the coast, and the shoreline retreat.</div>","PeriodicalId":50651,"journal":{"name":"Comptes Rendus Geoscience","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2019-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.crte.2018.10.004","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42932007","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 15

Page de Sommaire 目录页

IF 1.4 4区地球科学

Comptes Rendus Geoscience Pub Date : 2019-04-01 DOI: 10.1016/S1631-0713(19)30064-1

引用次数: 0