Skip to Main Content
Skip Nav Destination
GEOREF RECORD

Age constraints on the deformation style of the South Tibetan detachment system in Garhwal Himalaya

Chiara Montemagni, Salvatore Iaccarino, Chiara Montomoli, Rodolfo Carosi, Arvind K. Jain and Igor M. Villa
Age constraints on the deformation style of the South Tibetan detachment system in Garhwal Himalaya
Italian Journal of Geosciences (June 2018) 137 (2): 175-187

Abstract

In the Garhwal Himalaya, the Malari granite, a small pluton, intrudes the upper portion of the Greater Himalayan Sequence (GHS) and is deformed in the South Tibetan Detachment System (STDS) shearing. In the present work, we undertook a multidisciplinary approach involving microstructural, chemical and geochronological analyses of the samples in order to constrain the timing of shearing along the STDS. Microstructural observations of samples suggest a switch in deformation features with structural position from the structurally upper samples to the structurally lower one. X-ray maps and electron microprobe analyses reveal a quite uniform chemical composition of muscovite in the three selected samples. (super 40) Ar/ (super 39) Ar muscovite ages constrain the waning stages of ductile deformation: in rocks ductilely deformed by the STDS activity, they record recrystallization at 16.0-16.5 Ma; the age of static muscovite grown after sillimanite at 14.3 Ma post-dates cessation of movement on the STDS and pre-dates the main activity of the Main Central Thrust in the Western Himalaya.


ISSN: 2038-1719
EISSN: 2038-1727
Coden: BOGIAT
Serial Title: Italian Journal of Geosciences
Serial Volume: 137
Serial Issue: 2
Title: Age constraints on the deformation style of the South Tibetan detachment system in Garhwal Himalaya
Affiliation: Universita di Milano Bicocca, Dipartimento di Scienze dell'Ambiente e della Terra, Milan, Italy
Pages: 175-187
Published: 201806
Text Language: English
Publisher: Societa Geologica Italiana, Rome, Italy
References: 69
Accession Number: 2018-057574
Categories: GeochronologyStructural geology
Document Type: Serial
Bibliographic Level: Analytic
Illustration Description: illus. incl. 1 table, geol. sketch map
N30°40'00" - N30°45'00", E79°30'00" - E79°49'60"
Secondary Affiliation: Universita di Torino, ITA, ItalyUniversita di Pisa, ITA, ItalyCentral Building Research Institute, IND, IndiaUniversity of Bern, CHE, Switzerland
Country of Publication: Italy
Secondary Affiliation: GeoRef, Copyright 2018, American Geosciences Institute. Abstract, Copyright, Societa Geologica Italiana. Reference includes data from GeoScienceWorld, Alexandria, VA, United States
Update Code: 201831
Close Modal

or Create an Account

Close Modal
Close Modal