@misc{10481/72291,
year = {2021},
month = {9},
url = {http://hdl.handle.net/10481/72291},
abstract = {The Spontang Ophiolite complex represents the most complete ophiolite sequence amongst the South
Ladakh ophiolites and comprises mantle rocks (depleted harzburgites, dunites and minor lherzolites)
as well as crustal rocks (basalt, isotropic gabbros, layered gabbros etc.). In the present study, detailed geochemistry
(whole rock as well as mineral chemistry) and Sr-Nd isotopic analyses of thirty-six ultramaficmafic
samples have been attempted to constraint the evolution and petrogenetic history of the Tethyan
oceanic crust. Major, trace-element and REE patterns of the peridotites and their minerals indicate that
the lherzolites experienced lower degrees of partial melting resembling abyssal peridotites (at higher
temperatures, TREE =  1216  C) than the harzburgites (6%–8% versus 15%–17%). Elevated eNd(t) and variable
87Sr/86Sr(t) ratios along with REE patterns suggest that the Spontang mafic rocks display N-MORB
affinity with negligible participation of oceanic sediments in their genesis are originated from a depleted
upper mantle with little contribution from subduction-related fluids. MORB-type Neotethyan oceanic
crust is associated with the earliest phase of subduction (of older Jurassic age) through which a younger
intra-oceanic island arc (Spong arc) subsequently developed. Harzburgites REE display typical U-shaped
patterns, suggesting that these rocks have been metasomatized by LREE-enriched fluids. On the other
side, mafic rocks are characterized by heterogeneous (Nb/La)PM and (Hf/Sm)PM and relatively homogeneous
eNd(t), indicating interaction of subduction-related melts with the upper mantle during the initiation
of subduction, in Early Cretaceous times.},
organization = {Science Education and Research Board (SERB)},
organization = {Department of Science & Technology (India)	SR/FTP/ES-2/2014},
organization = {Women's scientist scheme	SR/WOS-A/EA-14/2017},
organization = {"Juan de la Cierva-formacion" Fellowship	FJC2018-036729},
organization = {Spanish Government},
organization = {European Social Fund (ESF)},
organization = {European Development Fund},
publisher = {Elsevier},
keywords = {Peridotites},
keywords = {Mafic rocks},
keywords = {Partial melting},
keywords = {Metasomatism},
keywords = {Ladakh},
title = {Geodynamic evolution of the Tethyan lithosphere as recorded in the Spontang Ophiolite, South Ladakh ophiolites (NW Himalaya, India)},
doi = {10.1016/j.gsf.2021.101297},
author = {Jonnalagadda, Mallika K. and Tilhac, Romain},
}