COLLABORATIVE RESEARCH: Carnian-Norian Magnetostratigraphy and Biostratigraphy at Silica Brezova (Slovakia)

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9417594 Kent High quality Carnian-Norian magnetostratigraphies derived recently from two marine sections in Turkey and a thick continental (lacustrine) section in the Newark Rift Basin are not easily correlated. The correlation even between the two Turkish sections is problematic, and is facilitated by supposing that the two condensed sections were in opposite hemispheres in Late Triassic time. A 200m thick Carnian-Norian (Upper Triassic) section at Silica Brezova (Slovakia) provides the opportunity to resolve the uncertainties in Carnian-Norian magnetostratigraphic correlations. The Silica Brezova section contains all Late Carnian and Norian conodont zones in an exceptionally thick (uncondensed) section of "Hallstatt Limestone" facies. The conodont alteration indices are close to 1, indicating no appreciable burial of the thrust unit which contains the section. A pilot magnetostratigraphic study on a 35m interval from the middle (Lacian) part of the Silica Brezova section has yielded a clear polarity zonation and a positive fold test. Magnetostratigraphy and biostratigraphy of the 200m Silica Brezova section should provide a first correlation of the high resolution cyclostratigraphy from the Neward Basin to the marine realm which is essential to the development of an integrated Late Triassic timescale linking marine and non-marine stratigraphies.