Geochronology of Pliocene volcanism in the Dzhavakheti Highland (the Lesser Caucasus). Part 1: Western part of the Dzhavakheti Highland

Petrogenesis of mafic collision zone magmatism: The Armenian sector of the Turkish–Iranian Plateau

“…There is a K-Ar groundmass age from a dolerite of the Akhurian river basin in Shirak of 2.5 ± 0.2 Ma (Chernyshev et al, 2002). Similar valley-filling flows in Southern Georgia are also dated using K-Ar methods to a range of 3-2 Ma (Lebedev et al, 2008a(Lebedev et al, , 2008b, confirming earlier assumptions from geological and palaeontological data (Shirtladze, 1958, Kharazyan, 1983. There is a switch in magnetic polarity between the lower and upper part of the Valley Series flow sequences, although several switches occurred during the Lower Pleistocene (Kharazyan and Shirinyan, 1981 and references therein; Cohen et al, 2013).…”

Absolute paleointensity determinations by using of conventional double-heating and multispecimen approaches on a Pliocene lava flow sequence from the Lesser Caucasus

“…Its basement is composed of Cretaceous and Paleogene volcanogenic sedimentary rocks that are overlain by the Neogene-Quaternary sequence of volcanic rocks emitted during three main stages ( Fig. 1): LateMiocene to Early Pliocene (8.3-4.8 My), Late-Pliocene to Early Pleistocene (4.0-1.8 Ma) and Late Pleistocene (less than 1.5 My) (Milanovskii and Koronovskii, 1973;Tutberidze, 2004;Lebedev and Dudauri, 2008).…”

“…The subaerial volcanism of the Djavakheti Highland and some other areas of Georgia is most likely related to processes of W-E extension causing emergence Lebedev and Dudauri, 2008;Calvo-Rathert et al, 2013) of the system of sub-meridian faults that served as conduits for the rising magma melts (Adamia et al, 2008). Its basement is composed of Cretaceous and Paleogene volcanogenic sedimentary rocks that are overlain by the Neogene-Quaternary sequence of volcanic rocks emitted during three main stages ( Fig.…”

“…From a petrological point of view, all Eshmakis Xevi lavas are similar to the three upper sites, except flow SR38, which presents mainly tholeiitic basalts. Lebedev and Dudauri (2008) had analyzed six samples from different horizons of the lower lava sequence, obtaining ages which varied between 2.23 and 2.03 Ma. Recently, a new K-Ar dating has been performed by Lebedev on a sample from the uppermost flow of the sequence (flow SR1 from the present study), yielding an age of 1.67 ± 0.13 Ma.…”

Intracanyon basalt lavas of the Debed River (northern Armenia), part of a Pliocene–Pleistocene continental flood basalt province in the South Caucasus

“…1), constitute the latest stages of the 11-2.7 Ma collisionrelated volcanism in this region. Lebedev et al (2007Lebedev et al ( , 2008a have provided geochemical data and K-Ar ages on the basalts of the Javakheti Plateau and discussed their regional stratigraphic correlations. They state that these lavas flowed along pre-existing river valleys for many tens of kilometres.…”