Matches in SemOpenAlex for { <https://semopenalex.org/work/W2022668670> ?p ?o ?g. }
- W2022668670 endingPage "165" @default.
- W2022668670 startingPage "127" @default.
- W2022668670 abstract "Archean–Proterozoic (AP) collision boundary in central Fennoscandia is a complex collage of Archean basement rocks, its Paleoproterozoic supracrustal cover rocks, and Svecofennian (1.93–1.78 Ga) supracrustal and plutonic rocks. The apparent steep nature and complexity of the AP boundary has led to contradictory tectonic models varying from arc-continent collision via back-arc closure to accretion of arc terranes along a strike-slip shear zone. We present new geochronology data from detrital zircons combined with whole-rock geochemical and Sm–Nd isotopic data on Paleoproterozoic sedimentary and volcanic rocks across the boundary to revise its nature. The 2.06 Ga Siilinjärvi volcanic complex and associated turbidites, with an inferred deposition age at 2.1–2.06 Ga, are part of the cover sequence. The Siilinjärvi volcanic rocks derive from both plume (OIB) and sub-continental lithospheric mantle (SCLM) magma sources and are often contaminated by the Archean crust. The Sahara suite sedimentary cover rocks are derived from local 1.95–1.92 Ga bimodal volcano-plutonic source, which source also explains the common age population found in younger sedimentary rocks. The Näläntöjärvi suite psammites, with maximum depositional ages of 1.97–1.93 Ga, are continental slope to deep water sediments deposited at the continental margin. Contemporaneous mafic magmatism, seen as lavas and dykes, show a change from SCLM dominated (present east) to asthenospheric depleted mantle (DM) dominated (present west) melts. The interpretation of the Näläntöjärvi suite as cover rocks of the lower plate indicates that the Archean crust continues at least 50 km more to the west than thought earlier. Parautochthonous sedimentary rocks from Salahmi, Eastern Kansanneva and Loutemäki with maximum depositional ages at 1.92–1.91 Ga are inferred as collision-related foredeep deposits from local sources. Both the Lampaanjärvi suite and Pyhäjärvi suite sedimentary rocks have deposited at 1.89–1.88 Ga or later, whereas the Lampaanjärvi suite rocks are dominated by a local source and the Pyhäjärvi suite rocks derive from a mixture of older sediments and 1.89–1.88 Ga granitoids. At least two tectono-metamorphic stages separated with a major unconformity can be differentiated in the study area. The early deformation and metamorphic stage in the Näläntöjärvi suite has occurred before the intrusion of the late- to post-collisional pyroxene granitoids at 1.88 Ga. The Pyhäjärvi suite sedimentary rocks have been deposited after the intrusion of these granitoids between 1880 and 1875 Ma and then subsequently deformed and metamorphosed at ≤1875 Ma. We propose a tectonic model where the continental breakup occurred at 2.1–2.06 Ga followed by a new spreading within the pre-existing passive margin at 1.98–1.93 Ga. During initial continent-arc collision the subducted slab steepened strongly at high angle, subduction ceased rapidly, and finally detached and shallow slab breakoff occurred at 1.92–1.91 Ga followed subsequently by ophiolite obduction and a formation of a foreland fold and thrust belt. Mantle-crust decoupling of the Archean lithosphere occurred and a crocodile jaw formed, where the arc rocks are partly buried beneath the bounding Archean continent. Similar features have been recorded in other AP collision zones, which could indicate that the buoyant nature of the Archean lithosphere combined with denser Paleoproterozoic lithosphere may be a general cause for decoupling of Archean crust and mantle during arc-continent collision in Paleoproterozoic." @default.
- W2022668670 created "2016-06-24" @default.
- W2022668670 creator A5003043249 @default.
- W2022668670 creator A5005472167 @default.
- W2022668670 creator A5008004259 @default.
- W2022668670 creator A5044588856 @default.
- W2022668670 creator A5052905126 @default.
- W2022668670 date "2015-05-01" @default.
- W2022668670 modified "2023-10-18" @default.
- W2022668670 title "Archean–Proterozoic collision boundary in central Fennoscandia: Revisited" @default.
- W2022668670 cites W148089723 @default.
- W2022668670 cites W1492175210 @default.
- W2022668670 cites W1587412370 @default.
- W2022668670 cites W1770170891 @default.
- W2022668670 cites W1952619490 @default.
- W2022668670 cites W1965114125 @default.
- W2022668670 cites W1966337473 @default.
- W2022668670 cites W1968474907 @default.
- W2022668670 cites W1969323155 @default.
- W2022668670 cites W1979682304 @default.
- W2022668670 cites W1990778953 @default.
- W2022668670 cites W1992069388 @default.
- W2022668670 cites W1993760980 @default.
- W2022668670 cites W1993968242 @default.
- W2022668670 cites W2001129033 @default.
- W2022668670 cites W2001426491 @default.
- W2022668670 cites W2004728143 @default.
- W2022668670 cites W2007105153 @default.
- W2022668670 cites W2015271064 @default.
- W2022668670 cites W2016241036 @default.
- W2022668670 cites W2020973699 @default.
- W2022668670 cites W2025140924 @default.
- W2022668670 cites W2032861618 @default.
- W2022668670 cites W2033244962 @default.
- W2022668670 cites W2033759679 @default.
- W2022668670 cites W2033962780 @default.
- W2022668670 cites W2034688166 @default.
- W2022668670 cites W2036480680 @default.
- W2022668670 cites W2039872199 @default.
- W2022668670 cites W2043810149 @default.
- W2022668670 cites W2046876080 @default.
- W2022668670 cites W2047364329 @default.
- W2022668670 cites W2048246159 @default.
- W2022668670 cites W2052681045 @default.
- W2022668670 cites W2059386668 @default.
- W2022668670 cites W2064301614 @default.
- W2022668670 cites W2068789641 @default.
- W2022668670 cites W2069211163 @default.
- W2022668670 cites W2070599361 @default.
- W2022668670 cites W2071497952 @default.
- W2022668670 cites W2073915589 @default.
- W2022668670 cites W2074593631 @default.
- W2022668670 cites W2080509668 @default.
- W2022668670 cites W2082784836 @default.
- W2022668670 cites W2083326010 @default.
- W2022668670 cites W2084396864 @default.
- W2022668670 cites W2093732601 @default.
- W2022668670 cites W2108971421 @default.
- W2022668670 cites W2122766310 @default.
- W2022668670 cites W2128437041 @default.
- W2022668670 cites W2136557397 @default.
- W2022668670 cites W2137854692 @default.
- W2022668670 cites W2141420220 @default.
- W2022668670 cites W2144663013 @default.
- W2022668670 cites W2145468835 @default.
- W2022668670 cites W2156460493 @default.
- W2022668670 cites W2156954089 @default.
- W2022668670 cites W2163661859 @default.
- W2022668670 cites W2171827043 @default.
- W2022668670 cites W2733542232 @default.
- W2022668670 doi "https://doi.org/10.1016/j.precamres.2015.02.012" @default.
- W2022668670 hasPublicationYear "2015" @default.
- W2022668670 type Work @default.
- W2022668670 sameAs 2022668670 @default.
- W2022668670 citedByCount "23" @default.
- W2022668670 countsByYear W20226686702015 @default.
- W2022668670 countsByYear W20226686702016 @default.
- W2022668670 countsByYear W20226686702017 @default.
- W2022668670 countsByYear W20226686702018 @default.
- W2022668670 countsByYear W20226686702019 @default.
- W2022668670 countsByYear W20226686702020 @default.
- W2022668670 countsByYear W20226686702021 @default.
- W2022668670 countsByYear W20226686702022 @default.
- W2022668670 countsByYear W20226686702023 @default.
- W2022668670 crossrefType "journal-article" @default.
- W2022668670 hasAuthorship W2022668670A5003043249 @default.
- W2022668670 hasAuthorship W2022668670A5005472167 @default.
- W2022668670 hasAuthorship W2022668670A5008004259 @default.
- W2022668670 hasAuthorship W2022668670A5044588856 @default.
- W2022668670 hasAuthorship W2022668670A5052905126 @default.
- W2022668670 hasConcept C120806208 @default.
- W2022668670 hasConcept C127313418 @default.
- W2022668670 hasConcept C141646446 @default.
- W2022668670 hasConcept C147717901 @default.
- W2022668670 hasConcept C149347711 @default.
- W2022668670 hasConcept C150999391 @default.
- W2022668670 hasConcept C151730666 @default.
- W2022668670 hasConcept C17409809 @default.