@misc{10481/71039,
year = {2021},
month = {7},
url = {http://hdl.handle.net/10481/71039},
abstract = {The Paleocene-Eocene Cerro Munro pluton, to the east of the North Patagonian Batholith (NPB), is a tonalitic
intrusion emplaced as a shallow, small, sub-circular tonalite-granodiorite body hosting abundant co-magmatic
mafic microgranular enclaves (MME). Besides, the intrusive body is crosscut by radial porphyritic dikes and
has been related to andesitic, dacitic and rhyolitic dikes, lava flows and ignimbrites cropping out at neighboring
areas. Magmatic contacts between MME and host tonalites, together with their common geochemical features,
suggest derivation from a common parental magma, although short-range mineralogical and geochemical differences
point to an early crystallization of MME (chilled margins) at the sidewalls of ascent conduits or at
shallow reservoirs. The established thermal gradient and the advance of the solidification front were responsible
for the presence of the mafic microgranular and tonalitic subsystems and, in a continuous process, promoted the
water saturation and the second boiling that finally account for the segregation of a water rich highly differentiated
residual liquid. Hbl-Pl cumulate textures observed in the tonalites and mafic enclaves, as well as
incompatible element-enriched rhyolitic melts record the results of this in-situ differentiation process. U–Pb
zircon ages obtained from tonalites (57.1 ± 1.4 Ma), dacitic (55.4 ± 0.6 Ma) and rhyolitic (54.1 ± 0.7 Ma) dikes
constrain an age of around 54 Ma for the final consolidation of the tonalitic magma and the crystallization of the
expelled highly differentiated melts. This age coincides with the deposition of dacitic volcanic and volcanoclastic
deposits to the north of the Cerro Munro pluton, which suggests that the fractionation process led to the extrusion
of segregated melts, favored by extension, uplift and exhumation of an active rift tectonic setting.},
organization = {IBERCRUST project	PGC2018-096534-B-I00},
organization = {AUIP grants (Asociacion Universitaria Iberoamericana de Postgrado)},
organization = {University of Huelva},
organization = {MINECO	CGL2017-84901-C2-P1},
publisher = {Elsevier},
keywords = {Calc-alkaline magmatism},
keywords = {Fractionation},
keywords = {Mafic microgranular enclaves},
keywords = {Second boiling},
keywords = {Geochronology},
keywords = {Cathodoluminiscence},
title = {Fractionation by compositional magma splitting: An example from Cerro Munro, Argentina},
doi = {10.1016/j.lithos.2021.106396},
author = {Rodríguez, Carmen and Castro, Antonio and Sánchez Navas, Antonio},
}