Superposed Folding in Nepheline Syenites and Associated Metamorphites Around Kishangarh, Rajasthan, India

Near Kishangarh in Rajasthan, Delhi conglomeratic quartzite and quartz mica schist overlie unconformably Aravalli metasediments. The foliation in the concordant nepheline syenites is parallel to the bedding plane foliation of the Aravallis. The Aravalli metasediments and the nepheline syenites show exactly similar development of superposed folds, with the axial surface of early isoclinal, inclined to reclined folds by nearly N-S striking upright folds. Evidence of such superposition is seen in all scales from hand specimens to maps. Spectacular outcrop patterns characteristic of superposed folds are developed. The effects of both the deformations can be seen only in the older Aravalli rocks and the nepheline syenites, while the younger Delhi rocks, in contrast, show only the later folds of the Aravalli rocks, which can be tied up with the first folding of the Delhi rocks.