Mafic volcanics of Raialo Group in Tehla area, Alwar sub-basin: First report of pillow lavas from the North Delhi Fold Belt, northwest India
MUKESH KUMAR BAIRWA M K PANDIT
Click here to view fulltext PDF
Permanent link:
https://www.ias.ac.in/article/fulltext/jess/130/0142
The rocks of Raialo Group in the Alwar sub-basin of North Delhi Fold Belt were investigated with a focus on meta-basic lava flows of the Tehla Formation. The basaltic rocks, now occurring as amphibolites, are medium- to fine-grained and show evidence of greenschist to lower amphibolite facies metamorphism, characterized by dominant plagioclase, hornblende, actinolite, chlorite, and minor, epidote, opaque, and Fe–Ti oxide mineral assemblage. The presence of amygdules and vesicles, well preserved primary igneous texture, and relict pyroxenes, at places, confirm their basaltic lineage. In a single outcrop, located to the northeast of Tehla village, well-preserved pillow structures have been discovered. The pillow structures vary in size (few cm to >1 m) and shape (spheroid, elongate and kidney-shaped), and inter-pillow spaces are filled up with chert, at places. This is the first report of pillow basalt occurrence from the North Delhi Fold Belt. In addition to offering evidence of submarine basaltic volcanism, the mega-pillows, gabbroic lenses, and presence of ultramafic rocks in the region suggest a possible ophiolite setting that needs a detailed petrographic and geochemical evaluation.
$\bf{Highlights}$
$\bullet$ First report of pillow structures from North Delhi Fold Belt.
$\bullet$ Identification of mafic- ultramafic association and possibility of an ophiolite setting.
MUKESH KUMAR BAIRWA1 M K PANDIT1
Volume 131, 2022
All articles
Continuous Article Publishing mode
Click here for Editorial Note on CAP Mode
© 2021-2022 Indian Academy of Sciences, Bengaluru.