Magnetostratigraphy of Early Cretaceous Maiolica sections of the Southern Alps (Cismon and Pra da Stua, Italy)
| العنوان: | Magnetostratigraphy of Early Cretaceous Maiolica sections of the Southern Alps (Cismon and Pra da Stua, Italy) |
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| المؤلفون: | Helmut Mayer |
| المصدر: | Geophysical Journal International. 131:387-400 |
| بيانات النشر: | Oxford University Press (OUP), 1997. |
| سنة النشر: | 1997 |
| مصطلحات موضوعية: | Paleontology, Geophysics, Geochemistry and Petrology, Remanence, Mesozoic, Clockwise, Cyclostratigraphy, Polarity chron, Cretaceous, Magnetostratigraphy, Geology, Latitude |
| الوصف: | SUMMARY The bottom part of the Cretaceous Cismon section in the Southern Alps was sampled for high-resolution magnetostratigraphy. Although the almost pure pelagic nannofossil limestones (c. 90 per cent CaCO,) of the Maiolica/Biancone Formation are extremely weakly magnetized, stepwise thermal and alternating-field demagnetization removed overprints and isolated a characteristic remanent magnetization which is interpreted as a primary magnetization. The dominant magnetic carrier mineral is magnetite; a small fraction of haematite may be present. A clear reversal pattern can be correlated unambiguously with Mesozoic polarity chrons CMlON to CM8. A less wellconstrained magnetostratigraphy from the Pra da Stua section could not be directly correlated with the global polarity scale, but biostratigraphic information allows its assignment to the interval CM10-CM5. A counterclockwise rotation of 56" and a northward translation of 28" latitude for the Cismon locality since the Early Cretaceous are derived from the palaeomagnetic data, consistent with previous results from the Southern Alps. The high-resolution magnetostratigraphy of the Cismon section is used in an effort to refine the Cretaceous timescale by the combination of magnetostratigraphic and cyclostratigraphic results from the same section. The cyclostratigraphic duration estimates of chrons CMlON to CM8 are compared to their equivalents in a number of traditional timescales and found to be shorter by a factor of 1.26-2.58. |
| تدمد: | 1365-246X 0956-540X |
| الوصول الحر: | https://explore.openaire.eu/search/publication?articleId=doi_________::8d3c2100eff3abcfc0d3af5622552869Test https://doi.org/10.1111/j.1365-246x.1997.tb01230.xTest |
| حقوق: | OPEN |
| رقم الانضمام: | edsair.doi...........8d3c2100eff3abcfc0d3af5622552869 |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 1365246X 0956540X |
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