No K/T boundary at Anjar, Gujarat, India: Evidence from magnetic susceptibility and carbon isotopes

Journal of Earth system science

D M Mohabey2²  H J Hansen1¹  P Toft1¹ 

[1] Geological Institute, Oster Voldgade 10, DK-1350, Denmark.$$;Geological Survey of India, Seminary Hills, Nagpur 440 006, India.$$

关键词: Iridium;    rhyolites;    paleomagnetics;    Deccan;    Lameta;   

DOI  :  

学科分类：天文学(综合)

来源: Indian Academy of Sciences

【 摘 要 】

The paper describes the variation pattern of magnetic susceptibility of Lameta sediments and isotopic variation of organic 13C from Chui Hill, Bergi, Kholdoda, Pisdura and Girad. The susceptibility pattern and a negative carbon isotopic anomaly allows fixation of the K/T boundary at these localities and they dier in these aspects from the inter-trappean sediments at Anjar.Paleomagnetic measurements of the Anjar sediment and the overlying basalt ow demonstrate reversed polarity. The Lameta sediments with dinosaur nests at Kheda and the overlying intertrappean sediments are of normal polarityThe clay layers at Anjar, associated closely with Ir-enrichments, are strongly leached, rhyolitic bentonites containing low-quartz paramorphs after high-quartz with glass inclusions.It is concluded, that the inter-trappean lake deposits at Anjar were deposited in the early part of magnetochron 29R and are unrelated to the K/T boundary.

【 授权许可】

Unknown