Mineralogy and phase-chemistry of the Cretaceous/Tertiary section in the Lattengebirge, Bavarian Alps
- Graup, G.
- JAN 1, 1988.
- Physical Description:
- 1 electronic document
- Restrictions on Access:
- Unclassified, Unlimited, Publicly available.
- The Lattengebirge K/T section reveals three distinct Ir spikes. Two of them are contained in the K/T transition zone sensu-strictu termed clayey interval, with 4.4 ppb Ir at the actual K/T boundary, and 2.8 ppb Ir 10 cm above the boundary. The highest Ir enrichment of 9 ppb, however, was detected in semi-cleaned organic material from a thin sandstone layer of Upper Maastrichtian age at 16 cm below the boundary. In this layer various discernible phases are preserved, contrasting with the worldwide observed K/T transition zones which are generally entirely composed of diagenetically altered materials. Given that, important clues to understanding the Cretaceous terminal events may be provided. The phases of the Cretaceous Ir bearing layer at Lattengebirge consist of: sandstone fragmental minerals in a carbonate matrix, coal which is partly burnt, melt glasses presumably of combustion-metamorphic origin, and sulfides, mainly chalcopyrite, contained in the coal. Like many known K/T sections and the Lattengebirge boundary sensu-strictu, the Cretaceous horizon is enriched in Ir and chalcophile elements as well. Although the Lattengebirge section offers the freshest materials, including melt glasses, of all K/T localities investigated, no unequivocal evidence of formation by impact has been found there.
- NASA Technical Reports Server (NTRS) Collection.
- Document ID: 19890011952.
Accession ID: 89N21323.
Lunar and Planetary Inst., Global Catastrophes in Earth History: An Interdisciplinary Conference on Impacts, Volcanism, and Mass Mortality; p 65.
- No Copyright.
View MARC record | catkey: 15691006