Palynology of the Siwalik sediments of Kala Amb-Nahan area in Sirmaur District, Himachal Pradesh

Abstract

The palynoflora recovered from the Lower Siwalik (Nahan) and Upper Siwalik sediments exposed along the road sections in Kala Amb-Nahan area in Sirmaur District consists of 18 genera and 25 species. Of these, two species are new. The diagnoses of two palynogenera, viz., Inaperturopollenites and Inapertisporites, have been emended. One new combination has also been proposed.

The Lower Siwalik (Nahan) palynoflora is represented by 13 genera and 17 species of fungal remains (13%), pteridophytic spores of Cyatheaceae and Polypodiaceae (5%), gymnospermous pollen of Pinaceae (73.5%), and angiospermous pollen of Liliaceae and Myricaceae (8.5%). On the other hand, the Upper Siwalik assemblage is represented by 11 genera and 15 species of fungal remains (14%), gymnospermous pollen of Pinaceae (67%), and angiospermous pollen of Potamogetonaceae, Palmae, Poaceae and Magnoliaceae (19%). A comparison of these Lower and Upper Siwalik assemblages with the known assemblages from the corresponding horizons has been made and it has been observed that the Lower Siwalik assemblage comes closest to that described from the Bhakra-Nangal Section in Himachal Pradesh, whereas the Upper Siwalik assemblage is comparable to the Pinjor assemblage near Chandigarh and Assemblage-1 of Hoshiarpur-Una Road Section assemblage.