A reconnaissance magnetostratigraphy of Georgian Plio- Quaternary volcanic provinces (southern Caucasus)

Abstract

A palaeomagnetic and rock magnetic study was carried out on samples of the Djavakheti, Khrami and Kazbeki regions in Georgia. Samples were taken from 44 localities from 247 subaerial lava flows and from 3 lacustrine sedimentary layers, interbed- ded between flows. Rock magnetic experiments showed that characteristic remanent magnetisation is mainly carried by magnetite of pseudo single domain size. 113 lava flows and 1 sedimentary layer yielded normal polarity magnetisation, 130 lava flows were reversly magnetised and 4 lava flows and 2 sedimentary layers displayed an intermediate polarity direction. A mean direction of D=4.7°, I=58.3°, k=28, á95=3.7° was obtained for all volcanic units, except those of intermediate polarity. A preliminary magnetostratigraphy of the Georgian volcanic provinces is proposed.