DC pole | Wartość | Język |
dc.contributor.author | Pandey, Om Prakash | - |
dc.contributor.author | Mezger, Klaus | - |
dc.contributor.author | Upadhyay, Dewashish | - |
dc.contributor.author | Paul, Debajyoti | - |
dc.contributor.author | Singh, Ajay Kumar | - |
dc.contributor.author | Söderlund, Ulf | - |
dc.contributor.author | Gumsley, Ashley | - |
dc.date.accessioned | 2021-01-19T13:39:57Z | - |
dc.date.available | 2021-01-19T13:39:57Z | - |
dc.date.issued | 2021 | - |
dc.identifier.citation | "Lithos" Vol. 382/383 (2021), art. no. 105959 | pl_PL |
dc.identifier.issn | 0024-4937 | - |
dc.identifier.uri | http://hdl.handle.net/20.500.12128/18490 | - |
dc.description.abstract | The SinghbhumCraton in eastern India is host to at least seven sets of mafic dyke swarms. Four previously dated
swarms (studied here) include the NNE-trending Keshargaria (ca. 2.80 Ga) and Ghatgaon (ca. 2.76 - 2.75 Ga)
swarms, the ENE-trending Kaptipada swarm (ca. 2.26 Ga), and the ESE-trending Pipilia swarm (ca.1.76 Ga).
The dykes range in composition from basalt to andesite and have transitional tholeiitic to calc-alkaline affinities.
They show intra- and inter-swarm geochemical and Sr-Nd isotopic heterogeneities and have SiO2 content ranging
from 47 to 60 wt.%. The chondrite normalized REE patterns show enrichment in LREE and the Primitive-
Mantle normalized multi-element patterns show elevated U, Th, Cs, Rb, K, and Pb; and depletion in Nb, Ta, and
Ti. These characteristics indicate involvement of crustal component in the petrogenesis of these dykes. The
dykes of different swarms have variable 87Sr/86Sri and εNd(i) values,which define a crust-like isotopic growth trajectory
with time from a common chondritic to depleted source that was enriched contemporaneously with the
formation of the crustal rocks of the Singhbhum Craton. The isotope data indicate involvement of older enriched
crustal material in the petrogenesis of these dykes. Variable but mostly high (compared to similarly evolved
magmas) Ni (40 - 590 ppm), Cr (40 - 1110 ppm), and V (120 - 434 ppm) contents particularly of the most primitive
dykes indicate that parental melts were in equilibrium with mantle peridotite and experienced only minor
fractional crystallization of olivine, pyroxene, and magnetite. The Sr-Nd isotope ratios do not show any correlation
with differentiation indices which indicates that the melts were not modified significantly by crustal assimilation
during ascent and emplacement. The crust-like secular trend of the Sr and Nd isotopic compositions
suggests that the enriched crustal materialwas incubated in themantle (i.e.,metasomatized lithospheric mantle)
for a long time and this source was periodically tapped leading tomultiple dykeemplacement events over at least
1 Gyr. The recycled crustal material played a role in metasomatizing the subcontinental lithospheric mantle prior
to ca. 2.80 Ga. Mantle plume activity triggered melting of the metasomatized lithospheric mantle many times,
leading to the emplacement of mafic dykes of different generations across the craton. | pl_PL |
dc.language.iso | en | pl_PL |
dc.rights | Uznanie autorstwa 3.0 Polska | * |
dc.rights.uri | http://creativecommons.org/licenses/by/3.0/pl/ | * |
dc.subject | Dyke swarm | pl_PL |
dc.subject | Indian Shield | pl_PL |
dc.subject | Large Igneous Provinces | pl_PL |
dc.subject | Neoarchean | pl_PL |
dc.subject | Paleoproterozoic | pl_PL |
dc.subject | SCLM | pl_PL |
dc.title | Major-trace element and Sr-Nd isotope compositions of mafic dykes of the Singhbhum Craton : insights into evolution of the lithospheric mantle | pl_PL |
dc.type | info:eu-repo/semantics/article | pl_PL |
dc.identifier.doi | 10.1016/j.lithos.2020.105959 | - |
Pojawia się w kolekcji: | Artykuły (WNP)
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