Age of Metamorphism of Delhi Supergroup Rocks - Electron Microprobe Ages from Mahendragarh District, Haryana

The subcalcic Fe-Mg amphibole rocks (anthophyllite-cummingtonite schist) are exposed in the Bayal area of Mahendragarh district in southern Haryana. These are considered to be hydrothermally altered mafic volcanic rocks metamorphosed to amphibolite facies. Monazite is present in association with cordienite and quartz in the anthophyllite-cummingtonite schist and texturally defines the metamorphic event in these rocks. In the present study two grains of Monazite from anthophyliite cummingtonite schist have been dated. Monazite grain in sample no 135 yielded an age 952±16 Ma while sample no 277 gave an age ot 945±14 Ma. This is inferred to be the age of metamorphism of rocks of Delhi Supergroup in Haryana.