000 03084nab a2200337 c 4500
001 vtls000581977
003 RU-ToGU
005 20230319211453.0
007 cr |
008 170913|2017 ne s a eng dd
024 7 _a10.1016/j.precamres.2017.03.001
_2doi
035 _ato000581977
040 _aRU-ToGU
_brus
_cRU-ToGU
245 1 2 _aA mantle plume origin for the Palaeoproterozoic Circum-Superior Large Igneous Province
_cT. J. Ciborowski, M. J. Minifie, A. C. Kerr [et.al.]
504 _aБиблиогр.: с. 210-213
520 3 _aThe Circum-Superior Large Igneous Province (LIP) consists predominantly of ultramafic-mafic lavas and sills with minor felsic components, distributed as various segments along the margins of the Superior Province craton. Ultramafic-mafic dykes and carbonatite complexes of the LIP also intrude the more central parts of the craton. Most of this magmatism occurred ∼1880 Ma. Previously a wide range of models have been proposed for the different segments of the CSLIP with the upper mantle as the source of magmatism. New major and trace element and Nd-Hf isotopic data reveal that the segments of the CSLIP can be treated as a single entity formed in a single tectonomagmatic environment. In contrast to most previous studies that have proposed a variety of geodynamic settings, the CSLIP is interpreted to have formed from a single mantle plume. Such an origin is consistent with the high MgO and Ni contents of the magmatic rocks, trace element signatures that similar to oceanic-plateaus and ocean island basalts and εNd-εHf isotopic signatures which are each more negative than those of the estimated depleted upper mantle at ∼1880 Ma. Further support for a mantle plume origin comes from calculated high degrees of partial melting, mantle potential temperatures significantly greater than estimated ambient Proterozoic mantle and the presence of a radiating dyke swarm. The location of most of the magmatic rocks along the Superior Province margins probably represents the deflection of plume material by the thick cratonic keel towards regions of thinner lithosphere at the craton margins. The primary magmas, generated by melting of the heterogeneous plume head, fractionated in magma chambers within the crust, and assimilated varying amounts of crustal material in the process.
653 _aмантийный плюм
653 _aпротерозой
655 4 _aстатьи в журналах
_9879358
700 1 _aCiborowski, T. Jake R.
_9418728
700 1 _aKerr, Andrew C.
_9418724
700 1 _aErnst, Richard E.
_9218658
700 1 _aBaragar, Bob
_9477573
700 1 _aMillar, Ian L.
_9477574
700 1 _aMinifie, Matthew J.
_9418727
773 0 _tPrecambrian research
_d2017
_gVol. 294. P. 189-213
_x0301-9268
852 4 _aRU-ToGU
856 7 _uhttp://vital.lib.tsu.ru/vital/access/manager/Repository/vtls:000581977
908 _aстатья
999 _c426501