Geochemistry of carbonate rocks in early Precambrian and phanerozoic metamorphic complexes of East Siberia, north-west of Russia, Pamir

Abstract

Geochemical study of carbonate rocks of Early-Precambrian and Phanerozoic metamorphic Complexes was carried out and their differences were revealed. Precambrian marbles and calciphyres studied in the Оnot Greenstone Belt, Kitoy and Sharyzhalgay granulitic Complexes Presayan uplift, Yenisei Series of the Angara-Kan Protrusion of the Siberian craton, the Belomorian and Lapland Complexes, North of the Pechenga Structure, Sortavala Suite of the Fennoscandian shield, Wakhan Complex of the Badakhshan Array; Phanerozoic – in Olkhon, Slyudyanka, Svyato nossky Complexes of the Baikal region, Boxon Series and Irkutnu Suite of the Eastern Sayan, Derbinsky Complex and Alchadur Suite of the Prisayan, Judin Suite and Panimba-Rybinsk Zone of the Yenisei Ridge, Muzkol Complex of the Eastern Pamirs. Precambrian carbonate rocks are enriched with Fe, Mn and depleted Sr, Ba in comparison with Phanerozoic rocks at a close low level of REE content. The Archean enrichment of Fe, Mn protoliths of marbles and calcifers is due to the dominance of basic and ultrabasic rocks in the feeding provinces. In the Paleoproterozoic, compared with the Phanerozoic, the proportion of Fe, Mn in carbonate rocks decreased, and Al, K, Ba, Sr have increased due to participation in occurrence their protoliths of the granite-metamorphic layer of the Earth. The distribution of petrogenic and rare elements in marbles and calcifirs is determined by the forms of their location: 1) in the isomorphic series of Ca-Mg carbonates with admixture of Fe, Mn, Ba, Sr, REE; 2) the presence of minerals Na, K, Ba, Sr in marbles; 3) location of thin (in marbles) and large (calcifications) fractions of minerals with iron, Mn Al, Ti, Zr, Cr, V, Ni, S. Performed paleoreconstruction behavior of REE in carbonate rocks in the Archean and Early-Paleoproterozoic dominated intracratonic shallow sea. Open oceans appeared at the turn of 2–1.9 billion years, but widespread development of carbonate rocks were in the Meso-Neoproterozoic and Phanerozoic. The revealed features are the basis of age-related paleoreconstructions of protoliths according to petrogeochemical characteristics of carbonate rocks of Precambrian and Phanerozoic metamorphic complexes.