Cretaceous age for Ir-rich Deccan intertrappean deposits: palaeontological evidence from Anjar, western India

被引:69
作者
Bajpai, S [1 ]
Prasad, GVR
机构
[1] Univ Roorkee, Dept Earth Sci, Roorkee 247667, Uttar Pradesh, India
[2] Univ Jammu, Dept Geol, Jammu 180004, India
关键词
Cretaceous; K-T boundary; Deccan traps; India; extinctions;
D O I
10.1144/jgs.157.2.257
中图分类号
P [天文学、地球科学];
学科分类号
07 [理学];
摘要
Micropalaeontological investigations of an iridium-bearing, lacustrine intertrappean sedimentary sequence at the western margin of the Deccan volcanic province near Anjar, have revealed a profuse occurrence of theropod eggshell fragments (ornithoid type) in beds overlying the iridium-enriched levels. Associated late Cretaceous ostracods, lack of evidence of reworking, and the absence of any exclusively Palaeocene taxa above the iridium levels, taken together, indicate that the extinction of dinosaurs in the Indian subcontinent occurred after the deposition of Ir layers at Anjar, and that these Ir anomalies may significantly predate the K-T boundary.
引用
收藏
页码:257 / 260
页数:4
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