Atlantic Geology最新文献_第8页

A revision of Annularia and Asterophyllites species from the lower Westphalian (Middle Pennsylvanian) of the Maritime Provinces of Canada 加拿大沿海省下威斯特伐利亚(中宾西法尼亚)的环虫属和星虫属物种订正

IF 1.6 4区地球科学

Atlantic Geology Pub Date : 2017-03-08 DOI: 10.4138/ATLGEOL.2017.002

C. Álvarez-Vázquez, R. Wagner

引用次数: 10

Ichnology of the Devonian (Emsian) Campbellton Formation, New Brunswick, Canada 加拿大新不伦瑞克省泥盆纪(Emsian) campbell组技术

IF 1.6 4区地球科学

Atlantic Geology Pub Date : 2017-02-08 DOI: 10.4138/ATLGEOL.2017.001

Olivia A. King, Randall F. Miller, M. Stimson

引用次数: 5

Bifurculapes Hitchcock 1858: a revision of the ichnogenus 希区柯克1858:鱼属的修订

IF 1.6 4区地球科学

Atlantic Geology Pub Date : 2017-01-13 DOI: 10.4138/ATLGEOL.2016.013

P. Getty

引用次数: 4

Atlantic Universities Geoscience Conference 2016: 66 th Annual Conference, October 27-29, 2016 2016年大西洋大学地球科学会议:第66届年会，2016年10月27-29日

IF 1.6 4区地球科学

Atlantic Geology Pub Date : 2016-12-12 DOI: 10.4138/ATLGEOL.2016.012

C. White

引用次数: 0

Silurian crinoids of the New Brunswick Museum, Saint John, Canada 加拿大圣约翰新不伦瑞克博物馆的志留纪海百合

IF 1.6 4区地球科学

Atlantic Geology Pub Date : 2016-11-26 DOI: 10.4138/ATLGEOL.2016.011

S. Donovan, Randall F. Miller

引用次数: 1

Fossil crinoids from the basal West Point Formation (Silurian), southeast Gaspé Peninsula, Québec, eastern Canada 加拿大东部quemassube半岛东南部西点组(志留系)基底海红色化石

IF 1.6 4区地球科学

Atlantic Geology Pub Date : 2016-11-10 DOI: 10.4138/ATLGEOL.2016.010

S. Donovan, D. Keighley

{"title":"Fossil crinoids from the basal West Point Formation (Silurian), southeast Gaspé Peninsula, Québec, eastern Canada","authors":"S. Donovan, D. Keighley","doi":"10.4138/ATLGEOL.2016.010","DOIUrl":"https://doi.org/10.4138/ATLGEOL.2016.010","url":null,"abstract":"Silurian strata of Atlantic Canada and southern Quebec locally preserve common fossil crinoids, albeit mostly as disarticulated remains. New crinoids from the Chaleurs Group, West Point Formation (Ludlow to Pridoli?; Upper Silurian) of the Gaspe Peninsula include Iocrinus ? maennili (Yeltysheva) (otherwise known from the Katian of Estonia), Bystrowicrinus (col.) depressus sp. nov. and Cyclocyclicus (col.) sp. aἀ. C. (col.) echinus Donovan. On the basis of both its gross morphology and stratigraphic position, Iocrinus ? maennili is unlikely to be an iocrinid disparid, a family that became extinct at the end of the Ordovician. The trivial name has hitherto been erroneously spelled as mannili , mannili and mjannili . Most specimens of the common Bystrowicrinus (col.) depressus appear cyclocyclic because the pentastellate lumen occurs in a deeply sunken claustrum that is commonly occluded by sediment; clean specimens are highly distinctive. Cyclocyclicus (col.) sp. aἀ. C. (col.) echinus is similar to a species known from the Katian of North Wales. Taken together, this assemblage is more reminiscent of Katian strata (Upper Ordovician). Ḁis is problematic given the current mapping of the outcrop as West Point Formation (Upper Silurian), suggesting further stratigraphic studies in the area are required.","PeriodicalId":49235,"journal":{"name":"Atlantic Geology","volume":"52 1","pages":"211-222"},"PeriodicalIF":1.6,"publicationDate":"2016-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70755226","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

Precise U-Pb ages for the cogenetic alkaline Mount LaTour and peraluminous Mount Elizabeth granites of the South Nepisiguit River Plutonic Suite, northern New Brunswick, Canada 加拿大新不伦瑞克省北部南内皮西特河深部岩浆岩套中同成碱性拉图尔山和过铝质伊丽莎白山花岗岩的精确U-Pb年龄

IF 1.6 4区地球科学

Atlantic Geology Pub Date : 2016-10-24 DOI: 10.4138/ATLGEOL.2016.009

Z. Azadbakht, C. McFarlane, D. Lentz

引用次数: 11

The Litchfield Pluton in South-Central Maine: Carboniferous Alkalic Magmatism in northern New England, USA 缅因州中南部的利奇菲尔德岩体:美国新英格兰北部石炭系碱性岩浆作用

IF 1.6 4区地球科学

Atlantic Geology Pub Date : 2016-06-30 DOI: 10.4138/ATLGEOL.2016.008

D. P. West, D. Bradley, R. Coish

{"title":"The Litchfield Pluton in South-Central Maine: Carboniferous Alkalic Magmatism in northern New England, USA","authors":"D. P. West, D. Bradley, R. Coish","doi":"10.4138/ATLGEOL.2016.008","DOIUrl":"https://doi.org/10.4138/ATLGEOL.2016.008","url":null,"abstract":"The Litchfield pluton is a poorly exposed 7 km 2 composite alkalic intrusive complex that cuts previously deformed and metamorphosed Silurian turbidites in south-central Maine. The pluton includes a variety of alkaline syenites, including the type locality of “litchfieldite”, a coarse-grained cancrinite, sodalite, and lepidomelane bearing nepheline syenite first recognized over 150 years ago and common in many petrologic collections. A new U-Pb zircon age of 321 ± 2 Ma from the nepheline syenite is interpreted to represent the crystallization age of the plutonic complex. A new biotite 40 Ar/ 39 Ar age of 239 ± 1 Ma from the syenite is similar to previously published mica ages from the surrounding country rocks and dates the time of regional cooling in the area below ~ 300°C. Whole rock geochemical analyses from rocks of the Litchfield pluton are compatible with strongly alkaline A-type granitoid rocks that formed in a within plate or continental rift tectonic setting. The age and geochemical characteristics of the alkalic igneous rocks near Litchfield are consistent with a model that invokes the generation of a small volume of alkalic magma beneath south-central Maine during a period of Carboniferous transcurrent tectonism in the northern Appalachian orogen.","PeriodicalId":49235,"journal":{"name":"Atlantic Geology","volume":"52 1","pages":"169-187"},"PeriodicalIF":1.6,"publicationDate":"2016-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70755064","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

Geochronology and lithogeochemistry of granitoid rocks from the central part of the Central plutonic belt, New Brunswick, Canada: implications for Sn-W-Mo exploration 加拿大新不伦瑞克省中央深部带中部花岗质岩石年代学和岩石地球化学:对Sn-W-Mo勘探的意义

IF 1.6 4区地球科学

Atlantic Geology Pub Date : 2016-04-29 DOI: 10.4138/ATLGEOL.2016.007

Reginald A. Wilson, S. Kamo

{"title":"Geochronology and lithogeochemistry of granitoid rocks from the central part of the Central plutonic belt, New Brunswick, Canada: implications for Sn-W-Mo exploration","authors":"Reginald A. Wilson, S. Kamo","doi":"10.4138/ATLGEOL.2016.007","DOIUrl":"https://doi.org/10.4138/ATLGEOL.2016.007","url":null,"abstract":"The central part of the Central plutonic belt in New Brunswick is underlain by numerous plutons of calc-alkaline, foliated and unfoliated granite that intrude Cambrian to Early Ordovician metasedimentary rocks. U-Pb (zircon) dating demonstrates that granites range in age from Middle Ordovician to Late Devonian, although most are late Silurian to Early Devonian. An age of 467 ± 7 Ma has been obtained on the foliated McKiel Lake Granite, whereas unfoliated intrusions yield ages of 423.2 ± 3.2 Ma (Bogan Brook Granodiorite), 420.7 +1.8/-2.0 Ma (Nashwaak Granite), 419.0 ± 0.5 Ma (Redstone Mountain Granite), 416.1 ± 0.5 Ma (Beadle Mountain Granite), 415.8 ± 0.3 Ma (Juniper Barren Granite), 409.7 ± 0.5 Ma (Lost Lake Granite), and 380.6 ± 0.3 Ma (Burnthill Granite). All plutons exhibit mixed arc-like and within-plate geochemical signatures, although the Redstone Mountain and Burnthill granites are dominantly of within-plate type. Trace element data reveal a close overall geochemical similarity between Ordovician and Silurian – Devonian plutons, indicating that all were generated by partial melting of the same crustal source. Late Silurian to Early Devonian plutons mainly comprise biotite and/or muscovite-bearing, peraluminous granite and are considered prospective for granophile-element mineralization. All plutons contain Sn well in excess of the granite global average abundance, and several contain average tin values comparable to productive stanniferous granites elsewhere. The Burnthill, Lost Lake, Beadle Mountain, and Nashwaak granites are geochemically most evolved and enriched in Sn and W. The Burnthill Granite in particular has experienced late-stage hydrothermal processes that have resulted in local enrichments of these elements.","PeriodicalId":49235,"journal":{"name":"Atlantic Geology","volume":"52 1","pages":"125-167"},"PeriodicalIF":1.6,"publicationDate":"2016-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70754891","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: 17

Megapezia longipes Willard and Cleaves 1930 from the Pennsylvanian Rhode Island Formation of Massachusetts: ichnotaxonomic status 威拉德和克利夫斯1930年发现于马萨诸塞州的宾夕法尼亚罗德岛地层:技术分类地位

IF 1.6 4区地球科学

Atlantic Geology Pub Date : 2016-04-10 DOI: 10.4138/ATLGEOL.2016.006

P. Getty

引用次数: 0