Canadian Journal of Earth Sciences最新文献_第5页

Seismic reflection stratigraphy of Lac Simard, Quebec, Canada: mass flow sedimentation in glacial Lake Barlow-Ojibway 加拿大魁北克Simard湖的地震反射地层学:Barlow-Ojibway冰川湖的物质流沉积

IF 1.4 4区地球科学

Canadian Journal of Earth Sciences Pub Date : 2023-06-08 DOI: 10.1139/cjes-2023-0027

A.J. Yu, N. Eyles, M. Doughty, S. Bukhari

{"title":"Seismic reflection stratigraphy of Lac Simard, Quebec, Canada: mass flow sedimentation in glacial Lake Barlow-Ojibway","authors":"A.J. Yu, N. Eyles, M. Doughty, S. Bukhari","doi":"10.1139/cjes-2023-0027","DOIUrl":"https://doi.org/10.1139/cjes-2023-0027","url":null,"abstract":"Lac Simard is a glaciated Shield basin situated in the Western Quebec Seismic Zone, an area of recurrent intraplate seismicity encompassing several densely populated areas. Previous works nearby have demonstrated that sediments preserved in lake basins hold the potential to serve as valuable archives of paleoseismicity. Correspondingly, a high-resolution chirp seismic reflection survey was conducted in Lac Simard, with results showing four acoustic facies (Af-1 to Af-4) within two stratigraphic successions (SS-1 and SS-2). The lowermost SS-1 is dominated by high-amplitude, laminated Af-2, interpreted as lateglacial varves deposited by suspension from primarily overflows and interflows during glacial lake ponding following deglaciation. Suspension deposition of Af-2 was episodically interrupted by stacked, chaotically bedded, weakly graded to opaque, channelled Af-3 interpreted as either debris flows or high-density turbidity currents. Presence of silt-clast breccias in Af-3 also suggests downslope collapse and reworking of varves from basin sidewalls. The overlying SS-2 is dominated by weakly reflective, laminated, high-frequency varved Af-4, suggesting a continuing seasonal control on postglacial sedimentation but with relative sediment starvation. A basin-wide erosional unconformity separating SS-1 and postglacial SS-2 records the abrupt drainage of glacial Lake Barlow-Ojibway around 8 000 years ago. Considering the history of lake floor disturbance in the region, mass flow facies Af-3 may be seismogenic, and thus, have regional tectonic significance. However, we cannot rule out the possibility of mass flows triggered by abrupt inflows of meltwater and sediment from a highly dynamic retreating Laurentide Ice Sheet prone to surging.","PeriodicalId":9567,"journal":{"name":"Canadian Journal of Earth Sciences","volume":"9 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2023-06-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78400587","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

Multiple forms of bioimmuration in a coral–crinoid–bryozoan association from the Middle Devonian Onondaga Formation of southeastern Ontario 安大略省东南部中泥盆世奥内达加组珊瑚-海百合-苔藓虫群落的多种生物免疫形式

4区地球科学

Canadian Journal of Earth Sciences Pub Date : 2023-06-01 DOI: 10.1139/cjes-2023-0002

James Thomka, Lilian Gunderson

{"title":"Multiple forms of bioimmuration in a coral–crinoid–bryozoan association from the Middle Devonian Onondaga Formation of southeastern Ontario","authors":"James Thomka, Lilian Gunderson","doi":"10.1139/cjes-2023-0002","DOIUrl":"https://doi.org/10.1139/cjes-2023-0002","url":null,"abstract":"A large favositid tabulate coral colony from the Middle Devonian Edgecliff Member of the Onondaga Formation, collected from Port Colborne, southernmost Ontario, is described herein because of several noteworthy paleontological features preserved via overgrowth by the coral. The initial substratum colonized and subsequently overgrown by the favositid was a large solitary rugose coral, and outward growth resulted in overgrowth of multiple macrofossils, including relatively long portions of large-diameter (probably camerate) crinoid columns. The crinoid columns, which likely represent portions of robust, recumbent dististelar attachment structures, are otherwise known almost entirely from isolated columnals at the collection locality and similar high-energy biostromal lithofacies in the Edgecliff Member elsewhere. One of the crinoid columns is encrusted by a stenolaemate bryozoan containing several examples of a parasitic bioclaustration structure similar to Catellocaula. Hence, the composite coral–crinoid–bryozoan association contains two forms of bioimmuration: preservation of the relatively intact crinoid columns via overgrowth and eventual incorporation into the base of the tabulate coral and preservation of the outline of the bioclaustrated organism (potentially an ascidian tunicate) via embedment in the bryozoan. This specimen serves as a testament to the diversity of biotic interactions and preservational mechanisms that occurred in Paleozoic carbonate build-ups.","PeriodicalId":9567,"journal":{"name":"Canadian Journal of Earth Sciences","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135727164","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

Paralava and clinker from the Canadian Arctic: A record of combustion metamorphism dating back to the late Miocene 加拿大北极地区的残岩和熟料:可追溯到中新世晚期的燃烧变质作用记录

IF 1.4 4区地球科学

Canadian Journal of Earth Sciences Pub Date : 2023-05-26 DOI: 10.1139/cjes-2022-0142

L. Reinhardt, Solveig Estrada, R. Dohrmann, Nikola Koglin, K. Piepjohn, J. Galloway

{"title":"Paralava and clinker from the Canadian Arctic: A record of combustion metamorphism dating back to the late Miocene","authors":"L. Reinhardt, Solveig Estrada, R. Dohrmann, Nikola Koglin, K. Piepjohn, J. Galloway","doi":"10.1139/cjes-2022-0142","DOIUrl":"https://doi.org/10.1139/cjes-2022-0142","url":null,"abstract":"Outcrops with conspicuous reddish to yellow-colored clinker, blackish paralava, and blends of both with a breccia-like appearance occur across the Canadian Arctic. We examined such rocks on Ellesmere Island, Banks Island, and the Mackenzie Delta area. These rocks are a product from natural combustion of bituminous shale and low-rank coal seams in Cretaceous and Paleogene host sedimentary rocks, respectively. The main mineral phases of clinker and silicate paralava samples are comprised of quartz + hematite ± feldspars ± cristobalite (or tridymite) ± cordierite–sekaninaite ± clinopyroxene ± sillimanite ± glass. Slag-like iron-oxide paralava (74–95 wt.% total Fe2O3) consisting of hematite ± magnetite ± clinopyroxene occur in Paleogene host sedimentary rocks rich in siderite concretions. The whole-rock geochemical composition of clinker and silicate paralava shows similarities for samples from the same outcrop. Regional and local specific elemental enrichments are mainly inherited from the sedimentary protoliths, which are characterized by volcanogenic input (Paleocene sedimentary rocks) or oxygen depleted depositional conditions (Upper Cretaceous bituminous sedimentary rocks). Spontaneous combustion could take place when the organic-rich sedimentary rocks become exposed to atmospheric oxygen. This process has occurred at least since the Messinian stage (Miocene) on Ellesmere Island (6.1 ± 0.2 Ma; 40Ar39Ar incremental heating dating on whole-rock paralava) and continues until now. An active combustion process on scree from a coal seam and clastic Eureka Sound Group sedimentary rocks was observed on Ellesmere Island.","PeriodicalId":9567,"journal":{"name":"Canadian Journal of Earth Sciences","volume":"19 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2023-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80724916","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

Petrogenesis and tectonic significance of the Early Cretaceous Xizhelimu diorite in Keyouzhongqi, Inner Mongolia, China 内蒙古可游中旗早白垩世喜直里木闪长岩成因及构造意义

IF 1.4 4区地球科学

Canadian Journal of Earth Sciences Pub Date : 2023-05-24 DOI: 10.1139/cjes-2022-0094

L. Tian, Deyou Sun, Jun Gou, Zhong-hua He, Duo Zhang

{"title":"Petrogenesis and tectonic significance of the Early Cretaceous Xizhelimu diorite in Keyouzhongqi, Inner Mongolia, China","authors":"L. Tian, Deyou Sun, Jun Gou, Zhong-hua He, Duo Zhang","doi":"10.1139/cjes-2022-0094","DOIUrl":"https://doi.org/10.1139/cjes-2022-0094","url":null,"abstract":"In order to determine the emplacement age, petrogenesis and geodynamic setting of the Xizhelimu diorite in Keyouzhongqi, Inner Mongolia of northeastern China, a detailed study of the petrography, geochronology and whole-rock geochemistry has been conducted. Geological and petrographic studies show that the Xizhelimu diorite is zoned: the central lithofacies zone is composed of medium-fine-grained monzodiorite and quartz diorite, and the marginal lithofacies zone is fine-grained diorite. The zircon U-Pb dating results show that the ages of the central and marginal facies are 133.5 ± 1.9 Ma and 133.4 ± 1.4 Ma, respectively. The whole-rock rare earth and trace element characteristics of the Xizhelimu diorite show an O-type adakite affinity. Combining the analysis of zircon Hf isotope composition (εHf(t) values of +7.7 to +10.0), the geochemical features of whole rock, and the results of partial melting modeling we suggest that the parental magma of the Xizhelimu diorite was derived from the partial melting of altered oceanic crust mixing with subducting sediments at shallow depths. In the early stage of Early Cretaceous, the Xizhelimu diorite originated in an extensional setting, mainly related to the closure of the western part of the Mongol–Okhotsk Ocean. The upwelling asthenospheric flow in this extensional setting induced partial melting of the paleo-oceanic crust to form the parental magma of the Xizhelimu diorite.","PeriodicalId":9567,"journal":{"name":"Canadian Journal of Earth Sciences","volume":"57 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2023-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74200772","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

Systematics and biostratigraphy of a new trilobite fauna collected from the subsurface Earlie Formation (Wuliuan Stage, Miaolingian Series, Cambrian) in southwestern Saskatchewan 萨斯喀彻温西南部寒武系苗岭系五流期地下早地层三叶虫新动物群的系统学与生物地层学

IF 1.4 4区地球科学

Canadian Journal of Earth Sciences Pub Date : 2023-05-19 DOI: 10.1139/cjes-2023-0003

N. M. Handkamer, Andrei Ichaso, B. Pratt, M. Mángano, L. Buatois

{"title":"Systematics and biostratigraphy of a new trilobite fauna collected from the subsurface Earlie Formation (Wuliuan Stage, Miaolingian Series, Cambrian) in southwestern Saskatchewan","authors":"N. M. Handkamer, Andrei Ichaso, B. Pratt, M. Mángano, L. Buatois","doi":"10.1139/cjes-2023-0003","DOIUrl":"https://doi.org/10.1139/cjes-2023-0003","url":null,"abstract":"Trilobites were recovered from four cores of the middle Cambrian Earlie Formation in southwestern Saskatchewan. Fossils occur in silty mudstone with interbedded siltstone and limestone, deposited in the inner detrital belt of the craton interior, under low-energy, subtidal conditions. Taxa identified include Kootenia dawsoni (Walcott 1889), Asaphiscus wheeleri Meek 1873, Blainia gregaria Walcott 1916b, Parehmania princeps Deiss 1939b, Ehmania weedi Resser 1935, Bolaspis labrosa (Walcott 1916a), and corynexochid gen. and sp. indet., indicating an age ranging from the lower to upper Altiocculus subzone of the Ehmaniella Zone, upper Wuliuan Stage. The upper Eldon and lower Pika formations located farther west in subsurface Alberta and the Rocky Mountains are considered to be age equivalent. Biostratigraphy confirms that strata overlying the Basal Sandstone Unit are diachronous and become progressively younger eastward. The trilobite fauna is lower in diversity relative to those in temporally equivalent units in the Rocky Mountains as well as the Great Basin, indicating that it may have experienced some environmental stressors, and that seafloor colonization was sporadic and opportunistic.","PeriodicalId":9567,"journal":{"name":"Canadian Journal of Earth Sciences","volume":"15 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2023-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82021116","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

Discussion: The Terreneuvian MacCodrum Brook section, Mira terrane, Cape Breton Island, Nova Scotia, Canada: age constraints from ash layers, organic-walled microfossils, and trace fossils 讨论:Terreneuvian MacCodrum Brook剖面，Mira terrane, Cape Breton Island, Nova Scotia, Canada:来自灰层，有机壁微化石和微量化石的年龄限制

IF 1.4 4区地球科学

Canadian Journal of Earth Sciences Pub Date : 2023-05-19 DOI: 10.1139/cjes-2023-0031

E. Landing, G. Geyer

引用次数: 2

Magnetotelluric imaging of the magmatic and geothermal systems beneath Mount Meager, southwestern Canada 加拿大西南部蒂尼山地下岩浆和地热系统的大地电磁成像

IF 1.4 4区地球科学

Canadian Journal of Earth Sciences Pub Date : 2023-05-11 DOI: 10.1139/cjes-2022-0136

C. Hanneson, M. Unsworth

{"title":"Magnetotelluric imaging of the magmatic and geothermal systems beneath Mount Meager, southwestern Canada","authors":"C. Hanneson, M. Unsworth","doi":"10.1139/cjes-2022-0136","DOIUrl":"https://doi.org/10.1139/cjes-2022-0136","url":null,"abstract":"Magnetotelluric data were collected on and around the Mount Meager Volcanic Complex, an active volcanic complex with eruptions ~2,400 and ~24,300 years ago. 3-D inversion was used to create an electrical resistivity model to a depth > 20 km. The model is characterized by high resistivity (> 100 Ωm) in the upper 6-7 km, implying relatively dry, unaltered rock. Within this resistive layer, localized conductors are observed in the upper 2 km beneath Pylon Peak and Fish Creek, corresponding to low-permeability clay-rich layers, acting as caprocks to geothermal fluids below. Beneath the resistive upper crust, there is a large conductor at ~5-15 km below sea level with an average resistivity of ~3 Ωm. Laboratory experiments of melt resistivity and petrological data from erupted volcanic rocks were used to interpret the model. The magma body (deep conductor) is inferred to have a minimum volume of ~2×10^12 m^3 comprising ~18-32% dacitic-to-trachydacitic melt with ~6-8 wt% H2O at a temperature of ~800-900ºC. This is below the melt fraction of an eruptible magma body. Resolution tests suggest it might be regional in extent, not localized beneath Mount Meager. There are fluid pathways from the northern part of the magma body, up toward Mount Meager and nearby fumaroles. This model is a significant advancement from its predecessors, created 20-40 years ago, providing the first deep 3-D image of this volcanic system. Along with other geophysical and geological models of the Garibaldi Geothermal Energy Project, it will reduce the exploration risk associated with geothermal energy development.","PeriodicalId":9567,"journal":{"name":"Canadian Journal of Earth Sciences","volume":"19 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2023-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82181800","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

Onshore–offshore correlation of central Lake Erie glacial deposits 伊利湖中部冰川沉积物的陆上-海上对比

IF 1.4 4区地球科学

Canadian Journal of Earth Sciences Pub Date : 2023-05-11 DOI: 10.1139/cjes-2023-0017

M. Lewis, G. Cameron, P. Barnett, B. Todd

{"title":"Onshore–offshore correlation of central Lake Erie glacial deposits","authors":"M. Lewis, G. Cameron, P. Barnett, B. Todd","doi":"10.1139/cjes-2023-0017","DOIUrl":"https://doi.org/10.1139/cjes-2023-0017","url":null,"abstract":"Dive observations, echogram transects, core sampling and a seismic profile revealed that the lake bed of north-central Lake Erie is an extensive terrace cut by storm waves and currents. The terrace is an erosional unconformity on which Late Wisconsinan (Port Bruce and Mackinaw) glacial units crop out. Beds of massive diamictons, and glaciolacustrine sediments containing parallel reflections, crop out alternately from west to east, resulting from an oscillatory ice retreat. These beds correlate with the Port Stanley Drift (Port Bruce phase) and Wentworth Drift (Mackinaw phase) exposed in nearby shore bluffs and onshore moraines. The Port Bruce glacier and earlier readvances formed ice tongues and ice shelves in the central basin. Diamicton layers, some with debris flows, constitute the Port Stanley Till (offshore units M and O). A glaciolacustrine unit N was deposited during Port Bruce glacier recessions. Glaciolacustrine unit P lies between Port Bruce unit O and the Mackinaw Wentworth Till, unit Q. A subsequent glaciolacustrine unit R overlaps unit Q. The onshore Galt and Moffat moraines, composed of Wentworth Till, correlate with ridges of the Norfolk moraine unit Q which extend across Lake Erie between the base of Long Point, Ontario, and Erie, Pennsylvania. The onshore Paris moraine appears to have been eroded on the wave-cut terrace and is evident offshore only near the south shore of Lake Erie. Laminated unit S, younger than unit R, occurs in the western part of central Erie basin, and correlates with overflow of Lake Algonquin from the Huron basin.","PeriodicalId":9567,"journal":{"name":"Canadian Journal of Earth Sciences","volume":"59 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2023-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73111093","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

Crustal eduction and slab-failure magmatism in an Orosirian (2.05−1.80 Ga) post-collisional cratonic foredeep: geochronology of Seton volcanics and Compton laccoliths, Tu Cho (Great Slave Lake), NWT, Canada orosiian (2.05 ~ 1.80 Ga)碰撞后克拉通前深的地壳喷发和板块破裂岩浆作用:加拿大Tu Cho (Great Slave Lake) Seton火山和Compton泥质岩的年代学

IF 1.4 4区地球科学

Canadian Journal of Earth Sciences Pub Date : 2023-05-01 DOI: 10.1139/cjes-2023-0011

P. Hoffman, F. Macdonald, S. Bowring, Ramezani JR Jahan, R. Buchwaldt, R. Hildebrand, J. Whalen

{"title":"Crustal eduction and slab-failure magmatism in an Orosirian (2.05−1.80 Ga) post-collisional cratonic foredeep: geochronology of Seton volcanics and Compton laccoliths, Tu Cho (Great Slave Lake), NWT, Canada","authors":"P. Hoffman, F. Macdonald, S. Bowring, Ramezani JR Jahan, R. Buchwaldt, R. Hildebrand, J. Whalen","doi":"10.1139/cjes-2023-0011","DOIUrl":"https://doi.org/10.1139/cjes-2023-0011","url":null,"abstract":"Three Orosirian basins and associated foreland thrust-fold belts are preserved on the margins of Slave craton. All three are related to orogenic belts where oceans opened and later closed uniting new crustal partners. Great Slave basin differs from Kilhigok and Coronation basins in ways that have defied explanation. It lacks a passive-margin sequence and hosts two discrete igneous suites, separated by large-scale thrusting, occurring well after the adjacent paleocean had closed. Here we report U-Pb zircon geochronology by CA-ID-TIMS for a member of each suite to constrain the age and origin of post-collisional thrusting. A widespread pulse of mainly phreatic alkaline volcanism, coeval with renewed foredeep flexure, occurred at 1889.0±0.7 Ma (2σ internal error). A quartz-monzodiorite body, one of a belt-parallel chain of laccoliths that postdate thrusting, was emplaced at 1866.9±0.9 Ma. These ages bracket renewed foredeep sedimentation and thrusting that telescoped major facies zones and was rooted within the basin. The older age is 70 and 30−60 Myr younger than collision in Thelon and Taltson orogen, respectively. We attribute post-collisional thrusting and foredeep subsidence to ‘eduction’—the upward and outward ejection of partly-subducted crust—and postulate that the top of the ejected wedge was a normal-sense detachment fault projecting beneath Nonacho basin. We infer that eduction was triggered by slab failure, producing alkaline volcanism, and ended with delamination and laccolith emplacement. Eduction was facilitated by tradewind–driven erosion. Delamination was enabled by crustal transfer to the educted wedge, reducing footwall buoyancy. Slab-failure and/or delamination removed the passive margin.","PeriodicalId":9567,"journal":{"name":"Canadian Journal of Earth Sciences","volume":"6 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2023-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86150570","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

Petrogenesis and geochemical evidence from Early Jurassic intrusive rocks and their implications for subduction of the Paleo-Pacific Plate in the Yanbian area, Northeast China 延边地区早侏罗世侵入岩的岩石成因、地球化学证据及其对古太平洋板块俯冲作用的启示

IF 1.4 4区地球科学

Canadian Journal of Earth Sciences Pub Date : 2023-04-27 DOI: 10.1139/cjes-2022-0119

xinwen zhang, Jing‐gui Sun, Zhikai Xu, Yang Liu, Chuntao Zhao

{"title":"Petrogenesis and geochemical evidence from Early Jurassic intrusive rocks and their implications for subduction of the Paleo-Pacific Plate in the Yanbian area, Northeast China","authors":"xinwen zhang, Jing‐gui Sun, Zhikai Xu, Yang Liu, Chuntao Zhao","doi":"10.1139/cjes-2022-0119","DOIUrl":"https://doi.org/10.1139/cjes-2022-0119","url":null,"abstract":"Subduction of the Paleo-Pacific Plate plays a key role in the Early Jurassic magmatism evolution in the Yanbian area, Northeast China. In this paper, zircon U–Pb ages, whole-rock geochemical and Sr–Nd–Hf isotopic compositions are presented. The Early Jurassic gabbros, diorite enclaves, granodiorites and granites ages range from 183 to 189 Ma. They are characterized by enrichment in LILEs and depletion in HFSEs. The gabbros are classified as low- and medium-K tholeiitic, granodiorites and granites are high-K calc-alkaline I-type, and diorite enclaves are calc-alkaline transitional series. The gabbros have zircon εHf(t) values of +6.81 to +9.89, whole-rock 87Sr/86Sr(i) = 0.7043-0.7044 and εNd(t) from +2.72 to +2.80. The diorite enclaves have zircons with εHf(t) values of +8.26 to +12.80, whole-rock 87Sr/86Sr(i) = 0.7051 and εNd(t) from +0.96 to +1.09. The granodiorites and granites have zircon εHf(t) values of +7.59 to +12.87, whole-rock 87Sr/86Sr(i) = 0.7042-0.7066 and εNd(t) from +2.33 to +2.61. These data indicate that gabbroic magmas were derived from partial melting of a depleted mantle wedge metasomatized by subduction-related fluids. The basaltic magma underplated and heated the juvenile crust, whereas the granodiorites and granites might be the product of fractional crystallization of a mixture of basaltic and felsic magmas or derived from partial melting of the juvenile lower crust. Our data constrain the petrogenesis of these Early Jurassic intrusive rocks which are attributed to subduction of the Paleo-Pacific Plate beneath Eurasia continent in northeastern China.","PeriodicalId":9567,"journal":{"name":"Canadian Journal of Earth Sciences","volume":"20 1","pages":""},"PeriodicalIF":1.4,"publicationDate":"2023-04-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79906908","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