Timing of continental arc-type magmatism in northwest India: Evidence from U-Pb zircon geochronology

Journal Article · Fri Sep 01 00:00:00 EDT 1989 · Journal of Geology; (USA)

DOI:https://doi.org/10.1086/629337· OSTI ID:6852455

Sarkar, G ^[1]; Barman, T R; Corfu, F ^[2]

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1. Geological Survey of India, Calcutta (India)
2. Royal Ontario Museum, Toronto (Canada)

Charnockites and granodiorites, which occur within granulite facies metasediments of the Bhilwara Supergroup of Rajasthan, northwest India, are cogenetic and exhibit petrologic characteristics indicative of a magmatic derivation. Zircon U-Pb data yield a common crystallization age of 1,723 + 14/ - 7 Ma. These rocks, earlier believed to represent oldest (Archean) and deepest crust, actually mark a major Proterozoic event. They are believed to be the products of continental arc magmatism, where a basic layer underplating the lower crust led to intrusion of differentiated melts in crustal domains undergoing dry metamorphism.

• OSTI ID: 6852455
• Journal Information: Journal of Geology; (USA), Vol. 97:5; ISSN 0022-1376
• Country of Publication: United States
• Language: English

Related Subjects

58 GEOSCIENCES
GEOLOGIC DEPOSITS
AGE ESTIMATION
INDIA
CRYSTALLIZATION
GEOLOGIC HISTORY
INTRUSION
ISOTOPE DATING
ISOTOPE RATIO
LEAD
LITHOLOGY
MAGMATISM
ORIGIN
PETROLOGY
PLATE TECTONICS
STRATIGRAPHY
URANIUM
ZIRCON
ACTINIDES
ASIA
DEVELOPING COUNTRIES
ELEMENTS
GEOLOGY
METALS
MINERALS
OXYGEN COMPOUNDS
PHASE TRANSFORMATIONS
SILICATE MINERALS
SILICATES
SILICON COMPOUNDS
TECTONICS
TRANSITION ELEMENT COMPOUNDS
ZIRCONIUM COMPOUNDS
ZIRCONIUM SILICATES
580000* - Geosciences