PRELIMINARY GEOCHEMISTRY AND EMPLACEMENT MECHANISM OF MAFIC DYKES OF ANANTAPUR AREA, ANDHRA-PRADESH

Authors
SARMA KJ
Citation
Kj. Sarma, PRELIMINARY GEOCHEMISTRY AND EMPLACEMENT MECHANISM OF MAFIC DYKES OF ANANTAPUR AREA, ANDHRA-PRADESH, Journal of the Geological Society of India, 49(4), 1997, pp. 409-416
Citations number
9
Categorie Soggetti
Geosciences, Interdisciplinary
Journal title
Journal of the Geological Society of India → ACNP
ISSN journal
00167622
Volume
49
Issue
4
Year of publication
1997
Pages
409 - 416
Database
ISI
SICI code
0016-7622(1997)49:4<409:PGAEMO>2.0.ZU;2-T
Abstract
The granite - gneiss terrain of Dharvar Craton in Anantapur area of An dhra Pradesh is intruded by mafic dolerite dykes. These dykes are quar tz or olivine-normative sub-alkalic tholeiites. Their Mg numbers range between 0.34 and 0.70 with low Ni(50-150 ppm), Cr(50-337 ppm) and Co( 41-70 ppm), indicating some degree of fractionation. The REE abundance s show LREE - enriched patterns (La/Yb-N - 2.7 to 5.5). These dykes ap pear to be genetically related and were derived from a single magma.