Collaborative Research: Carnian-Norian Magnetostratigraphy and Biostratigraphy at Silica Brezova (Slovakia)

最近从土耳其的两个海相剖面和Newark裂谷盆地的一个厚大陆（湖相）剖面得到的高质量的卡尼—诺里期磁地层学不容易对比。即使是两个土耳其部分之间的相关性也是有问题的，假设这两个浓缩的部分在晚三叠纪时期位于相反的半球，这就简化了。斯洛伐克Silica Brezova地区200米厚的卡尼—诺里期（上三叠统）剖面为解决卡尼—诺里期磁地层对比的不确定性提供了机会。石英布雷佐瓦剖面包含了所有晚卡尼期和诺里期牙形石带，位于“哈尔斯塔特灰岩”相的一个异常厚（未凝结）的剖面中。牙形石蚀变指数接近1，表明包含该剖面的逆冲单元没有明显的埋藏。在距二氧化硅布雷左瓦剖面中部（拉西亚）35米的区间进行的初步磁地层学研究得出了明确的极性分带和积极的褶皱测试。200米石英Brezova剖面的磁地层学和生物地层学应该提供从纽沃德盆地到海洋领域的高分辨率旋回地层学的第一次对比，这对于建立连接海洋和非海洋地层学的晚三叠世综合时间尺度至关重要。

9417895 Channell 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.