气候变化领域集成服务门户(CCPortal): An Integrated Paleomagnetic, Multimethod-Paleointensity, and Radiometric Study on Cretaceous and Paleogene Lavas From the Lesser Caucasus: Geomagnetic and Tectonic Implications

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DOI	10.1029/2020JB020019
	An Integrated Paleomagnetic, Multimethod-Paleointensity, and Radiometric Study on Cretaceous and Paleogene Lavas From the Lesser Caucasus: Geomagnetic and Tectonic Implications
	Calvo-Rathert M.; Bógalo M.F.; Morales J.; Goguitchaichvili A.; Lebedev V.A.; Vashakidze G.; García-Redondo N.; Herrero-Bervera E.
发表日期	2021
ISSN	21699313
卷号	126 期号:2
英文摘要	Sixteen rhyolitic and dacitic Cretaceous and Paleocene-Eocene lavas from the Lesser Caucasus have been subjected to paleomagnetic and multimethod paleointensity experiments to analyze the variations of the Earth's magnetic field. Paleointensity experiments were performed with two methods. Thellier-type experiments with the IZZI method on 65 specimens (nine flows) yielded 15 successful determinations and experiments with the multispecimen method on 14 samples (seven flows) yielded two successful determinations. The joint analysis of the results obtained with both methods produced a mean FuK = (19.9 ± 3.7) µT for upper Cretaceous and FPg = (20.7 ± 3.3) µT for Paleogene sites. Low virtual axial dipole moments for the Cretaceous (3.4 × 1022 Am2) and Paleogene (3.5 × 1022 Am2) samples support the idea of a lower average dipole moment during periods of stable polarity of the Earth magnetic field. Mean flow paleomagnetic directions did not match expected upper Cretaceous to Paleogene directions calculated from the European Apparent Polar Wander Path. While inclination results roughly agreed with expected values, a group of sites showed nearly North-South paleodeclinations (D = 1.1° ± 14.2°), and another group displayed eastward deviated paleodeclinations (D = 72.9° ± 26.6°). These results suggest the occurrence of nearly vertical-axis rotations, probably as a result of continental collision since Oligocene. In addition to paleomagnetic and palaeointensity analyses, new K-Ar absolute age determinations have been performed on three of the studied sites, yielding Late Cretaceous ages (78.7 ± 1.7, 79.7 ± 1.6, and 83.4 ± 1.8 Ma (2σ)). © 2020. American Geophysical Union. All Rights Reserved.
英文关键词	Caucasus; Cretaceous; K-Ar dating; Paleointensity; Paleomagnetism; Rock magnetism
语种	英语
来源期刊	Journal of Geophysical Research: Solid Earth
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/187352
作者单位	Departamento de Física, EPS, Universidad de Burgos, Burgos, Spain; Hawaii Institute of Geophysics and Planetology, SOEST, University of Hawaii at Manoa, Honolulu, HI, United States; Laboratorio Interinstitucional de Magnetismo Natural, Instituto de Geofísica Unidad Michoacán, UNAM, Morelia, Mexico; Institute of Geology of Ore Deposits, Petrography, Mineralogy and Geochemistry—Russian Academy of Sciences (IGEM RAS), Moscow, Russian Federation; Alexandre Janelidze Institute of Geology—Ivane Javakhishvili Tbilisi State University, Tbilisi, Georgia
推荐引用方式 GB/T 7714	Calvo-Rathert M.,Bógalo M.F.,Morales J.,et al. An Integrated Paleomagnetic, Multimethod-Paleointensity, and Radiometric Study on Cretaceous and Paleogene Lavas From the Lesser Caucasus: Geomagnetic and Tectonic Implications[J],2021,126(2).
APA	Calvo-Rathert M..,Bógalo M.F..,Morales J..,Goguitchaichvili A..,Lebedev V.A..,...&Herrero-Bervera E..(2021).An Integrated Paleomagnetic, Multimethod-Paleointensity, and Radiometric Study on Cretaceous and Paleogene Lavas From the Lesser Caucasus: Geomagnetic and Tectonic Implications.Journal of Geophysical Research: Solid Earth,126(2).
MLA	Calvo-Rathert M.,et al."An Integrated Paleomagnetic, Multimethod-Paleointensity, and Radiometric Study on Cretaceous and Paleogene Lavas From the Lesser Caucasus: Geomagnetic and Tectonic Implications".Journal of Geophysical Research: Solid Earth 126.2(2021).