Bulletin of the Geological Society of Finland最新文献_第3页

Constraints over the age of magmatism and subsequent deformation for the Neoarchean Kukkola Gneiss Complex, northern Fennoscandia Fennoscandia北部新太古代Kukkola片麻岩杂岩岩浆作用年龄和随后变形的制约因素

IF 0.7 4区地球科学

Bulletin of the Geological Society of Finland Pub Date : 2020-06-15 DOI: 10.17741/bgsf/92.1.002

P. Skyttä, M. Määttä, Simo Piippo, Jaakko Kara, A. Käpyaho, E. Heilimo, H. O’Brien, Palsatech Oy

{"title":"Constraints over the age of magmatism and subsequent deformation for the Neoarchean Kukkola Gneiss Complex, northern Fennoscandia","authors":"P. Skyttä, M. Määttä, Simo Piippo, Jaakko Kara, A. Käpyaho, E. Heilimo, H. O’Brien, Palsatech Oy","doi":"10.17741/bgsf/92.1.002","DOIUrl":"https://doi.org/10.17741/bgsf/92.1.002","url":null,"abstract":"The Archean crust in northern Fennoscandia preserves a fragmentary geological record, making direct correlation among Archean domains challenging. This study presents two new zircon U-Pb age determinations from the Archean Kukkola Gneiss Complex (KGC) that straddles the border between Finland and Sweden. The results indicate that crystallization of tonalites within the magmatic core of the complex occurred at 2711±8 Ma, somewhat earlier than previously considered. A new pulse of magmatism occurred at 2675±10 Ma as demonstrated by hornblende-tonalites cutting the 2.71 Ga rocks. The results further indicate that the first deformation event responsible for development of penetrative foliations occurred after the first magmatic event at 2.71 Ga and prior to the subsequent tectonothermal event at 2.68 Ga. These findings are in concert with the known major periods of magmatism (2.8–2.7 Ga) and deformation (2.7 Ga) within better-known Archean domains in northern Fennoscandia, and hence support their correlation with KGC. Three complementary age determinations on the Haparanda-suite granites and tonalites were conducted: the results indicate crystallization ages of 1.90–1.89 Ga, overlapping with the known age range of the suite and supporting its predominance over the 1.8 Ga Lina suite granites in the TornioHaparanda area.","PeriodicalId":55302,"journal":{"name":"Bulletin of the Geological Society of Finland","volume":"92 1","pages":"19-38"},"PeriodicalIF":0.7,"publicationDate":"2020-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47679860","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: 3

Age and origin of the Nb-Zr-REE mineralization in the Paleoproterozoic A1-type granitoids at Otanmäki, central Finland 芬兰中部Otanmäki古元古代a1型花岗岩中Nb-Zr-REE矿化年龄及成因

IF 0.7 4区地球科学

Bulletin of the Geological Society of Finland Pub Date : 2020-06-15 DOI: 10.17741/bgsf/92.1.003

K. Kärenlampi, A. Kontinen, E. Hanski, H. Huhma, Y. Lahaye, J. Krause, T. Heinig

{"title":"Age and origin of the Nb-Zr-REE mineralization in the Paleoproterozoic A1-type granitoids at Otanmäki, central Finland","authors":"K. Kärenlampi, A. Kontinen, E. Hanski, H. Huhma, Y. Lahaye, J. Krause, T. Heinig","doi":"10.17741/bgsf/92.1.003","DOIUrl":"https://doi.org/10.17741/bgsf/92.1.003","url":null,"abstract":"The Otanmäki area in central Finland hosts two occurrences of Nb-Zr-REE mineralization, Katajakangas and Kontioaho, within a suite of ca. 2.04–2.06 Ga (A1-type) gneissic granites, syenite and monzonite-monzodiorite. They exhibit trace element characteristics and whole-rock εNd(2050 Ma) values (from +2.6 to -1.3) consistent with derivation by differentiation of mantle-derived mafic magmas with variable interaction with crustal material. The mineralization is localized in 0.1to 1.4-m-thick dikes (Katajakangas) and a 30to 50-m-thick sheet-like body (Kontioaho), containing allanite-(Ce), zircon, titanite, and Nb-REE-Th-U oxides. Their wall rocks are composed of ca. 2.06 Ga peraluminous monzogranite, which is genetically unrelated to the mineralized rock units, as evidenced by whole-rock chemical and Sm-Nd isotope data and zircon U-Pb geochronology. Instead, the mineralization is linked to the nearby peralkaline to metaluminous alkali feldspar granite magmatism dated at ca. 2.04–2.05 Ga. The development of REE-HFSE enrichment in the mineralized rock units required extensive crystallization of a peralkaline granite magma, producing residual metaluminous, highsilica melts enriched in REE-HFSE, Ca, and Fe relative to Na, K, and Al. The REE-HFSE and Ca enrichment was further promoted by volatile complexing with dissolved F-, CO3 2and SO4 2-. These highly evolved melts were parental to the mineralized dikes and the sheet-like intrusive body, which were emplaced into the monzogranite capping the intrusions of peralkaline granite.","PeriodicalId":55302,"journal":{"name":"Bulletin of the Geological Society of Finland","volume":"92 1","pages":"39-71"},"PeriodicalIF":0.7,"publicationDate":"2020-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47088802","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

Some new insights into the geochronology of the Western Karelia Subprovince, Finnish Lapland 芬兰拉普兰西卡累利阿省地质年代学的一些新见解

IF 0.7 4区地球科学

Bulletin of the Geological Society of Finland Pub Date : 2020-06-15 DOI: 10.17741/bgsf/92.1.001

Johanna Tepsell, T. Rämö, A. Heinonen, Y. Lahaye, Pieti Haapala, T. Halkoaho, J. Heinonen, Henri Höytiä, J. Konnunaho, V. Järvinen

{"title":"Some new insights into the geochronology of the Western Karelia Subprovince, Finnish Lapland","authors":"Johanna Tepsell, T. Rämö, A. Heinonen, Y. Lahaye, Pieti Haapala, T. Halkoaho, J. Heinonen, Henri Höytiä, J. Konnunaho, V. Järvinen","doi":"10.17741/bgsf/92.1.001","DOIUrl":"https://doi.org/10.17741/bgsf/92.1.001","url":null,"abstract":"Archean terranes are generally poorly exposed and structurally complicated, making models of geological evolution difficult to establish. Because of pervasive metamorphism, strong deformation, and poorly exposed bedrock, the stratigraphy, geochronology, and geological evolution of the northeastern part of the Archean Western Karelia Subprovince, Finnish Lapland, is still deficient. Three new U-Pb age determinations were made using the LA-ICP-MS method on zircon in search of more profound understanding of the geochronology of the area. Data from the Pultoselkä granite yield an age of 2795±5 Ma, providing a minimum age of 2.8 Ga for the Tulppio suite. The age is coeval with widespread 2.74–2.70 Ga granitoids of the Karelia Province, likely representing the same magmatic event. The data from the Kontioselkä pegmatite define a maximum age for the pegmatite and a minimum age for mafic volcanic rocks in Kontioselkä at 1781±27 Ma. The age coincides with major deformation and metamorphism in the Karelia Province around 1.76 Ga. Zircon from the Jänesselkä mafic-ultramafic complex yields a minimum age of 2425±17 Ma, complying rather well with the 2.5–2.4 Ga mafic layered intrusions of the northern Fennoscandian Shield. Our new data show that the Archean of the northeastern part of the Western Karelia Subprovince was affected by Proterozoic thermal events more extensively than thus far perceived.","PeriodicalId":55302,"journal":{"name":"Bulletin of the Geological Society of Finland","volume":"92 1","pages":"5-17"},"PeriodicalIF":0.7,"publicationDate":"2020-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48150474","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

The 1.79 Ga Särkilahti leucogranite – a horizontal magma layer below granulite-grade migmatites in SE Finland 芬兰东南部1.79 Ga Särkilahti浅花岗岩体——麻粒级混辉岩下方的水平岩浆层

IF 0.7 4区地球科学

Bulletin of the Geological Society of Finland Pub Date : 2019-12-04 DOI: 10.17741/bgsf/91.2.003

H. Mäkitie, H. O’Brien, O. Selonen, M. Kurhila, Turku Finland Mineralogy

引用次数: 2

Zn-Pb-Cu sulfide-bearing glacial sandstone erratics near Raahe on the western coast of Finland: Indicators of Paleozoic base metal mineralization at the bottom of the Bothnian Bay 芬兰西海岸Raahe附近含Zn-Pb-Cu硫化物的冰川砂岩：波的尼亚湾底部古生代基底金属矿化的指标

IF 0.7 4区地球科学

Bulletin of the Geological Society of Finland Pub Date : 2019-12-04 DOI: 10.17741/bgsf/91.2.001

E. Hanski, H. Huhma, Y. Lahaye, J. Lunkka, E. Nilsson, T. Mäki, H. O’Brien, K. Strand, Mountain View Usa Atle Arctica

引用次数: 1

Biases in radiocarbon dating of organic fractions in sediments from meromictic and seasonally hypoxic lakes 亚罗米质湖泊和季节性缺氧湖泊沉积物中有机组分放射性碳年代测定的偏差

IF 0.7 4区地球科学

Bulletin of the Geological Society of Finland Pub Date : 2019-12-04 DOI: 10.17741/bgsf/91.2.004

A. Ojala, M. Saarnisto, H. Jungner, I. Snowball, R. Muscheler

引用次数: 2

Magnesite soapstone in use of fire chamber constructions: composition and structure adaptation 菱镁矿皂石在消防室建筑中的应用：成分和结构适应性

IF 0.7 4区地球科学

Bulletin of the Geological Society of Finland Pub Date : 2019-06-12 DOI: 10.17741/BGSF/91.1.004

A. Huhta, P. Tuisku, T. Balić-Žunić, A. Kärki, Kivitieto Oy

{"title":"Magnesite soapstone in use of fire chamber constructions: composition and structure adaptation","authors":"A. Huhta, P. Tuisku, T. Balić-Žunić, A. Kärki, Kivitieto Oy","doi":"10.17741/BGSF/91.1.004","DOIUrl":"https://doi.org/10.17741/BGSF/91.1.004","url":null,"abstract":"The Finnish soapstone industry has found through practical experience that the surface of the magnesite soapstone used in fire chambers and funnels hardens over time. We have studied a magnesite soapstone used in a fireplace continuously for 60 years. The mineralogical changes, that took place during heating and subsequent cooling of the fireplace have been investigated with electron probe microanalyzer and X-ray diffractometer to find an explanation, what kind of reactions caused the hardening. We found that ferromagnesite has been altered to pseudomorphic aggregates composed of ferropericlase and magnesioferrite in the nearest ~30 mm from the surface exposed to fire. Iron has been mobilized in the uppermost 3 mm, enriched in the rims, and depleted from the cores of the ferropericlase aggregates. Magnesioferrite occurs preferably in the fire chamber side of the aggregates in the uppermost 0.20 mm. Talc rims are altered to forsterite and/or enstatite in the reaction with ferromagnesite or its alteration products in the uppermost ~1 mm. In addition, wood combustion gases caused considerable enrichment of zinc and potassium in the chamber surface rock to the depth on 0.20 mm and 3 mm, respectively. The enrichment occurred by crystallization of Zn bearing ferropericlase and magnesioferrite and by crystallization of K bearing sheet silicates.","PeriodicalId":55302,"journal":{"name":"Bulletin of the Geological Society of Finland","volume":"1 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2019-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41364504","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

Baltic Ice Lake levels and a LiDAR/DEM-based estimate of the glacio-isostatic uplift gradient of the Salpausselkä zone, SE Finland 波罗的海冰湖水位和基于激光雷达/ dem的芬兰东南部Salpausselkä地区冰川均衡隆起梯度估算

IF 0.7 4区地球科学

Bulletin of the Geological Society of Finland Pub Date : 2019-06-12 DOI: 10.17741/BGSF/91.1.005

J. Lunkka, T. Nikarmaa, N. Putkinen

{"title":"Baltic Ice Lake levels and a LiDAR/DEM-based estimate of the glacio-isostatic uplift gradient of the Salpausselkä zone, SE Finland","authors":"J. Lunkka, T. Nikarmaa, N. Putkinen","doi":"10.17741/BGSF/91.1.005","DOIUrl":"https://doi.org/10.17741/BGSF/91.1.005","url":null,"abstract":"Glaciofluvial ice-contact deltas were mapped and altitudes of the highest shorelines defined in the eastern arc of the Salpausselkä zone, southern Finland, using Light Detection and Ranging (LiDAR)-based digital elevation models and GIS tools. Mapping of deltas and the highest shorelines in the Salpausselkä zone were undertaken in order to calculate and define the glacio-isostatic uplift palaeo-isobases, uplift gradients and equidistant diagrams (distance diagrams) for the Salpausselkä zone. The results indicate that the glacio-isostatic uplift palaeo-isobases were orientated NE-SW (50°–230°) and the uplift gradients for both the First and the Second Salpausselkä in the eastern arc, are virtually the same, namely 0.6 mkm-1. This suggests that both Salpausselkä ridge complexes, which were originally laid down in front of the Finnish Lake District Ice Lobe (FLDIL) in relatively shallow water, were deposited within a short time period during the Late Weichselian Younger Dryas Stadial. The results also suggest that the Baltic Ice Lake water level regressed 7.5 metres from Baltic Ice Lake level B I to level B III as the ice retreated in its eastern arc from the First to the Second Salpausselkä.","PeriodicalId":55302,"journal":{"name":"Bulletin of the Geological Society of Finland","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2019-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45474246","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

Geology, geochronology and geochemistry of the 2.05 Ga gneissic A1-type granites and related intermediate rocks in central Finland: implication for the tectonic evolution of the Karelia craton margin 芬兰中部2.05 Ga片麻质a1型花岗岩及相关中间岩的地质、年代学和地球化学:对卡累利阿克拉通边缘构造演化的启示

IF 0.7 4区地球科学

Bulletin of the Geological Society of Finland Pub Date : 2019-06-12 DOI: 10.17741/BGSF/91.1.002

K. Kärenlampi, A. Kontinen, H. Huhma, E. Hanski

{"title":"Geology, geochronology and geochemistry of the 2.05 Ga gneissic A1-type granites and related intermediate rocks in central Finland: implication for the tectonic evolution of the Karelia craton margin","authors":"K. Kärenlampi, A. Kontinen, H. Huhma, E. Hanski","doi":"10.17741/BGSF/91.1.002","DOIUrl":"https://doi.org/10.17741/BGSF/91.1.002","url":null,"abstract":"The 2.05 Ga Otanmäki suite represents a globally rare occurrence of Paleoproterozoic non-orogenic A1-type magmatism. It consists of a broad variety of A-type felsic and intermediate igneous rocks including monzodiorites, monzonites, syenites and peralkaline to peraluminous granites, containing both plutonic and subvolcanic members. The suite has chemical characteristics similar to those of A1-type suites formed in intraplate hotspots or continental rifts by differentiation of variably crustally contaminated, mafic mantle-derived magmas. However, compared to the Otanmäki rocks, most A1-type suites are considerably younger. original geologic because the suite deformed metamorphosed under amphibolite facies C, kbar) orogeny i.e., initial emplacement. result, Otanmäki pervasively foliated rocks within two nappe units sandwiched between Archean granitoid gneiss of 1950 Ma ocean-continent-transition ophiolitic rocks in the same thrust belt and the proximity of the Otanmäki suite to the Karelia-Svecofennia margin suggest that the suite records an early stage of a slow, ca. 100-Ma-long extension-rifting process which, at ca. 1950 Ma, eventually led to the final break-up of the Karelia craton and formation of the nascent ocean basin witnessed by the Jormua ophiolite complex.","PeriodicalId":55302,"journal":{"name":"Bulletin of the Geological Society of Finland","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2019-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41754264","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: 5

Tracing the styles of mafic-felsic magma interaction: A case study from the Ahvenisto igneous complex, Finland 镁质-长英质岩浆相互作用样式的追踪:以芬兰阿文尼斯托火成岩杂岩为例

IF 0.7 4区地球科学

Bulletin of the Geological Society of Finland Pub Date : 2019-06-12 DOI: 10.17741/BGSF/91.1.001

Riikka Fred, A. Heinonen, Pasi Heikkilä

{"title":"Tracing the styles of mafic-felsic magma interaction: A case study from the Ahvenisto igneous complex, Finland","authors":"Riikka Fred, A. Heinonen, Pasi Heikkilä","doi":"10.17741/BGSF/91.1.001","DOIUrl":"https://doi.org/10.17741/BGSF/91.1.001","url":null,"abstract":"The 1.64 Ga Ahvenisto complex, southeastern Finland, is an anorthosite-mangeritecharnokite-granite (AMCG) suite in which diverse interaction styles of coeval mafic and felsic magmas are observed. Commingling, resulting in mafic pillows and net-veined granite dykes, and chemical mixing producing hybrid rocks, are the most common interaction types. Detailed description of the factors that controlled the interaction styles and relationships between involved rock types are provided using targeted mapping, petrography, and geochemical analyses complemented by chemical mixing and melt viscosity modeling. Interaction occurred at intermediate stages in the magmatic evolution of the complex: when the last fractions of mafic (monzodioritic) melts and the earliest fractions of felsic (hornblende granitic) melts existed simultaneously. Differentiation of mafic magma has produced three monzodioritic rock types: 1) olivine monzodiorite (most mafic, Mg# 49–40), 2) ferrodiorite (Mg# 42–33), and 3) massive monzodiorite (most evolved, Mg# 28–27). The types form an evolutionary trend, and each exhibits different style of interaction with coeval hbl-granite resulting from contrasting conditions and properties (temperature, viscosity, composition). The variation in these properties due to magma evolution and relative proportions of interacting magmas dictated the interaction style: interaction between olivine monzodiorites and granite was almost negligible; ferrodiorites intermingled forming pillows with granitic veins intruding them; and chemical mixing of massive monzodiorite and hbl-granite produced hybrid rocks.","PeriodicalId":55302,"journal":{"name":"Bulletin of the Geological Society of Finland","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2019-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41925578","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: 4