Geochemsitry of distinct mafic intrusive rocks from Darba-Kukanar and Kerlapal-Sukma-Mokhpal areas, southern Bastar Craton; further data on the early Precambrian mafic magmatism of central India

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Authors:Srivastava, Rajesh K.; Gautam, Gulab C.
Author Affiliations:Primary:
Banaras Hindu University, Department of Geology, Varanasi, India
Volume Title:Journal of the Geological Society of India
Source:Journal of the Geological Society of India, 69(6), p.1176-1188. Publisher: Geological Society of India, Bangalore, India. ISSN: 0016-7622
Publication Date:2007
Note:In English. 36 refs.; illus., incl. 2 tables, geol. sketch maps
Summary:Geochemistry of mafic igneous rocks of early Precambrian age of the southern Bastar craton in and around Darba-Kukanar and Kerlapal-Sukma-Mokhpal areas are presented. Most of these mafic rocks occur as NW-Se trending dykes intruded into the Archean granite/granite-gneiss and over metamorphic rocks. Few intrusive also occur as sills or plutonic bodies. On the basis of field relationships between mafic rocks and other exposed rock types and also between the mafic rocks, available geochronological data, petrological and geochemical characteristics, the studied mafic rocks are classified into three main types: (i) Group I (BDI): Mesoarchaen mafic rocks, metamorphosed under mid-amphibolite facies conditions, showing concentration of high-field strength element (HFSE) higher than the Group 3 (boninite-norite) mafic rocks, and lower than the Group 2 (BD2: dolerite-diorite), (ii) Group 2 (BD2): Paleoproterozoic mafic rocks of dolerite-diorite composition, characterized by higher concentration of HFSE than the other two types, and (iii) Group 3 (BN: boninite-norite): Neoarchaean mafic rocks, metamorphosed under greenschist-amphibolite transitional conditions, characteristically showing high-Mg and Si, very low-Ti, and HFSE composition close to boninite. These observations are very similar to the previously studied mafic rock from the other parts of the southern Bastar craton. It is suggested that the BDI mafic rocks are derived from depleted sub-alkaline basaltic magma, whereas enriched sub-alkaline basaltic magma was responsible for the BD2 mafic rock. High-Mg boninite-norite (BN) mafic rocks were probably derived from a primary boninitic magma originated from a refractory lherzolitic mantle source. These observations clearly suggest heterogeneous mantle source beneath the Baster craton during the early Precambrian.
Subsections:Igneous rocks
Subjects:Andesites; Archean; Boninite; Dikes; Emission spectra; Gabbros; High-field-strength elements; ICP mass spectra; Igneous rocks; Intrusions; Mafic composition; Magmatism; Major elements; Mass spectra; Metals; Mg number; Norite; Petrography; Plutonic rocks; Precambrian; Rare earths; Spectra; Trace elements; Volcanic rocks; Asia; Bastar Craton; Bastar India; Chhattisgarh India; India; Indian Peninsula; ICP optical emission spectra; Optical emission spectra
Coordinates:N181500 N190000 E0820000 E0811500
Abstract Numbers:07M/2211
Record ID:2008067856
Copyright Information:GeoRef, Copyright 2019 American Geosciences Institute.
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