BIOSTRATIGRAPHIC IMPLICATIONS OF THE RECORD OF GENUS HIMALAYITES FROM THE LATE TITHONIAN SEDIMENTS OF JAISALMER, WESTERN INDIA

摘要

The occurrence of genus Himalayites Uhlig enables interprovincial correlation of Late Tithonian sediments worldwide. Recently, the occurrence of this genus was recorded from Kachchh (western India) and the distribution is now extended to the adjoining Jaisalmer basin. H. aff. seideli (Oppel) [M] is now recorded from the Rupsi Shale Member. Preliminary data from this Member indicates the creation of four new ammonite biozones - Alterniplicatus, Virgatosphinctoides, Kobelliforme and Himalayites. The earliest zone, Alterniplicatus, is marked by the abundance of Torquatisphinctes (T. alterneplicatus), followed by Virgatosphinctes (V. densiplicatus and V. sp.), a restricted and dominant occurrence of Hildoglochiceras (H. kobelliforme, H. latistrigatum, H. nodosum and H. cf. planum) and the topmost Zone is marked by the first appearance of the Late Tithonian genus Himalayites, respectively. The Alterniplicatus Zone is correlated with the latest Early Kimmeridgian Tethyan Divisum Zone, Virgatosphinctoides with Early Tithonian Darwini Zone, Kobelliforme with Early Tithonian Semiforme Zone and Himalayites with latest Tithonian Durangites spp. Zone.