Cis-Caspian region

Earth’s Magnetic Field Evolution During Last 24 mln Years

Authors: Grebenuk L. V.

The history of Earth’s magnetic field during the last 24mln years is considered in terms of our regional magnetostratigraphic Neogene scheme of the southern European Russia and Transcaucasian region. The scheme results from the author’s paleomagnetic studies of base sections in the Caucasian region and bore holes in the northern Cis-Caspian and Lower Volga regions. The revealed inversions of the geomagnetic field are referenced to the stratigraphic scale of the Eastern Para-Tethys. Peculiarities of the magnetic polarity changes in Neogene are analyzed.

Petromagnetic Indicators of Layers with High Concentration of Cosmogenic Substance in Maastrichtian of Volga Region and Cis-Caspian Region

Authors: Gujikova A. A., Tselmovich V. A., Atkin V. S.

The level with anomalous high values of natural remanent magnetization and Koenigsberger ratios was identify in the Upper Maastrichtian of Vol’sk depression (Saratov Volga Region). The microprobe studies of samples from this layer registered elevated concentrations of microparticles of iron, nickel, intermetallics and magnetite spherules of cosmic genesis. Similar petromagnetic anomaly was detect in the uppermost of Maastrichtian in the South Cis-Caspian (Aktolagay Plateau, Kazakhstan).