TERRAPUB Earth, Planets and Space

Earth Planets Space, Vol. 61 (No. 1), pp. 23-39, 2009

Rock magnetic and paleointensity results from Mesozoic baked contacts of Armenia

V. V. Shcherbakova1, M. Perrin2, V. P. Shcherbakov1, V. E. Pavlov3, A. Ayvaz'yan4, and G. V. Zhidkov1

1Borok Geophysical Observatory, Schmidt Institute of Physics of the Earth, Russian Academy of Sciences, Borok, Russia
2Geosciences Montpellier, UMR CNRS/UM2 5243, Université Montpellier II, France
3Schmidt Institute of Physics of the Earth (IPE), Russian Academy of Sciences, Moscow, Russia
4Yerevan State University, Departament of Geology, Armenia

(Received December 24, 2007; Revised March 17, 2008; Accepted March 20, 2008; Online published January 23, 2009)

Abstract: Samples were obtained from three baked contacts and one lava flow along the upper Turonian-lower Coniacian Tovuz section, two baked contacts along the upper Coniacian-lower Santonian Paravakar section in the northern part of Armenia, and three baked contacts along the Titonian-Valanginian Kafan section in southern Armenia. A total of 130 samples were studied. Updated mean paleomagnetic poles were calculated for the Upper Cretaceous Tovuz-Paravakar sections (65.6°N, 162.2°E, A95 = 4.3, paleolatitude = 27.0 ± 3.4°) and the Upper Jurassic-Lower Cretaceous Kafan section (61.7°N, 158.9°E, A95 = 4.8°, paleolatitude = 24.7 ± 3.8°). Paleointensity determinations could be estimated from two of the upper Cretaceous and three of the Upper Jurassic-Lower Cretaceous baked contacts, corresponding to a 30% success rate. The mean virtual dipole moments obtained were low (1.7-5.5 × 1022 A m2), which is in agreement with data published by Bol'shakov and Solodovnikov (1981a, 1983) for the same sections (3.0-4.4 × 1022 A m2). Our results support the hypothesis of the Mesozoic Dipole Low, even though the overall data are widely dispersed.
Key words: Paleointensity, Armenia, Cretaceous, baked contacts, Thellier method.

Corresponding author E-mail: shcherb@borok.yar.ru

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