Late iocene Palandoken Caldera, its role on formation and tectonics of Erzurum Basin, Eastern Turkiye

Palandoken Caldera recently recognized and stated first in this article. Erzurum Basin Deep basement for the EFZ basins, consists of late Cretaceous obducted ophiolite melange, Erzurum Basin is girt to South by volcanic rocks of Palandoken Ranges and to North by Dumlubaba Ranges. Kargapazarı high volcanic plateau lying to the east of the basin. Neogene volcanites of the North Eastern Anatolia (Erzurum, Ardahan, Kars, Agri) belong to the nephelin-normative (alkaline) basalts (havayit, mugearit, quartzous trachites etc) and benmorit. During Quaternary time volcanites of high-potassium, calc-alkali order (dacites, rhyolites) as well as leucite-bearing alkali rocks were formed, as well. In Kars-Erzurum and Agri Dag volcanic areas, there are differentiated basalt-andesite-dacite-rhyolitite series with rare subalkaline varieties. Together with them, one can observe basalts, dolerites and sometimes basaltic andesites and their subalkaline varieties. This whole unit is overlain by angular unconformity by Palandoken volcanics including calc-alkaline basaltic lavas, volcanic breccias and accumulations of scoriaceous materials. Pyroclastic lithology dominantly include silisic ignimbrites, breccias and tuffs of trachytic and rhyolitic composition. This whole unit is overlain by angular unconformity by Palandoken volcanics including calc-alkaline basaltic lavas, volcanic breccias and accumulations of scoriaceous materials. Pyroclastic lithology dominantly include silisic ignimbrites, breccias and tuffs of trachytic and rhyolitic composition. Kargapazarı basaltic volcanics lie unconformably above all units older then Pleistocene, formed flat-topped hills and plateau. Dark colored ignimbrites are common elements. Trachytic plug (and intrusives structures) occur at severa ۱ places, near N margin. in response to N-S tectonic shortening. Simultaneous activity of these two fault types has led to the common development of oblique slip faults. Rotation and folding of fault surfaces and thrusts, and their later reuse caused complications in structural development. Erzurum Basin, has very distinct morpho-tectonic features revealed pronounced asymmetry between N and S margins. Overall picture of compressional tectonic regime resulted in over- steepening of slopes, catastrophic mass movements and thrust-related landforms which indicates inversion to compression and associated volcanism. South of the Basin, the basement consists of a series of south dipping thrust slices. North of the Basin, has different structure form south, is accompanied by basin floor, indicates ongoing flooding and thrusting. The only units exposed are late Miocene-Pliocene volcanics, which are openly folded and cut by steep