Skip to Main Content
Skip Nav Destination
GEOREF RECORD

Early Paleozoic intrusives of the Kuznetsk Alatau, Siberia; isotopic evidence of oceanic lithosphere participation in sources

V. V. Vrublevskii, I. F. Gertner and A. D. Kotelnikov
Early Paleozoic intrusives of the Kuznetsk Alatau, Siberia; isotopic evidence of oceanic lithosphere participation in sources (in Goldschmidt abstracts 2013, Anonymous)
Mineralogical Magazine (2013) 77 (5): 2433

Abstract

Products of the Early Paleozoic intrusive magmatism are represented in the Kuznetsk Alatau (KA) by granitoid, gabbro-syenite, and alkali basite complexes. They were formed during the period of about 510-490 Ma, which is in the Central Asian fold belt. The magmatic activity implies the presence of multi-component melt sources with age that close to the age of the oceanic lithosphere formation. Nd-Sr isotopic signatures discovered for four studied complexes formed in different ways indicate possible participation of Paleo-Asian Ocean (PAO) lithosphere in the processes of magma generation at the Early Paleozoic stage of this ocean's evolution. The oldest complexes (about 510 Ma) are the differentiated series from gabbro to granodiorite as well as alkaline basic complexes. Despite the petrogenetic differences, these complexes have similar isotopic composition of Nd (epsilon Nd (sub T) approximately +4,8...+5,0). Such values are typical either for magmatic derivatives of moderately depleted mantle, or for mixing products of DMM or PREMA reservoirs with EM-type mantle and continental crust materials. The influence of crust contamination is seen in high ratio of Sr-isotopes in the rocks (epsilon Sr (sub T) approximately +1...+28). Granitoids and gabbro-syenite series with the age of about 500-490 Ma don't have significantly different Nd-isotopic compositions (epsilon Nd (sub T) approximately +3,5...+4,6). Apparently, it is confirmed by narrow range of these T(Nd) (sub DM) values ( approximately 0,8-0,9 Ga). According to different views, the beginning of the Rodinia supercontinent's break-up, and following the PAO opening are estimated to be 970-800 Ma Based on our data, Sm-Nd isotopic age of ultrabasites and gabbroids of the layered series and restite suites varies from 955 to 890 Ma, respectively. Magmatism probably developed under the conditions of plume interacting with active continental margin coupled with MORB+PREMA+EM matter mixing.


ISSN: 0026-461X
EISSN: 1471-8022
Serial Title: Mineralogical Magazine
Serial Volume: 77
Serial Issue: 5
Title: Early Paleozoic intrusives of the Kuznetsk Alatau, Siberia; isotopic evidence of oceanic lithosphere participation in sources
Title: Goldschmidt abstracts 2013
Author(s): Vrublevskii, V. V.Gertner, I. F.Kotelnikov, A. D.
Author(s): Anonymous
Affiliation: Tomsk State University, Tomsk, Russian Federation
Pages: 2433
Published: 2013
Text Language: English
Publisher: Mineralogical Society, London, United Kingdom
Meeting name: Goldschmidt 2013
Meeting location: Florence, ITA, Italy
Meeting date: 20130825Aug. 25-30, 2013
References: 3
Summary: Y
Accession Number: 2014-048223
Categories: Igneous and metamorphic petrology
Document Type: Serial Conference document
Bibliographic Level: Analytic
N52°00'00" - N56°15'00", E82°30'00" - E89°00'00"
Country of Publication: United Kingdom
Secondary Affiliation: GeoRef, Copyright 2017, American Geosciences Institute. Abstract, Copyright, Mineralogical Society of Great Britain and Ireland
Update Code: 201427
Close Modal

or Create an Account

Close Modal
Close Modal