Tectonostratigraphic characteristics of the area between Cayeli (Rize) and Ispir (Erzurum)

Abstract

The study area is located in the Eastern Pontides between Rize, Cayeli, Arhavi, Ispir and Ikizdere. In this area, Macka Tectonic Slice (MTS) and Taskopru Tectonic Slice (TTS) are exposed. MTS is composed from old to young; Late Jurassic-Early Cretaceous limestone (Berdiga fm.); Turonian-Santonian conglomerate, sandstone, micritic limestone, siltstone, marl, basaltic, basaltic-andesitic lava, pyroclastites (Catak fm.); Santonian rhyolitic, dacitic lava, pyroclastites, sandstone, clayey limestone (Kizilkaya fm.); late Santonian-Campanian basaltic, andesitic lava, pyroclastites, sandstone, clayey limestone (Caglayan fm.); Campanian-Mastrihtian rhyolitic, dacitic lava, pyroclastites, sandstone, clayey limestone (Cayirbag fm.);late Maastrichtian-Danian sandstone, claystone, tuff, marl, clayey limestone (Cankurtaran fm.). Sedimentary, volcanosedimentary units in the Late Paleocene-Quaternary range (Erenler, Kaplica, Melyat, Pazar, Hamidiye formations, and Handuzu, Cagirankaya volcanites) unconformably overlies the MTS. In the study area, Turonian-Maastrichtian basaltic andesitic lavas, pyroclastites and sandstone, micritic limestone, claystone units (Yagmurdere fm.) belonging to TTS are observed, and Early-Middle Eocene sedimentary and volcanosedimentary units (Yedigoze, Coruh formations) unconformably overlies the TTS. According to Ar/Ar dating, Cayrrbag formation was determined as 83.2 +/- 1.0 Ma, Melyat formation as 47.8 +/- 1.6 Ma, and Handuzu volcanics as 4.25 +/- 0.55 Ma for andesite level and as 3.93 +/- 0.46 Ma for dacite level. The MTS was intruded by Cretaceous-Paleocene Kackar granitoid I, Eocene Kackar granitoid II, Late Eocene Ardesen gabbro, while the TTS was intruded by Cretaceous-Paleocene Kackar granitoid-I, Late Eocene Gullubag monzonite.