Geology, petrography and geochemistry of andesites at the Eastern end of Küçük Menderes Graben (Başova-Kiraz/İzmir)

Abstract

The studied area is located in the eastern end of Kil9ilk: Menderes Graben. The basement consis1;sor Menderes Massif metamorphIc rOCks. These are CUI by young volcanies cropped out an the NE. E and SE of Kiraz..around Ba,ov8. Kaf8bu~ and YeniteOOvillages in order. The volcanic rocks outcrop on a line in NE.sW trend as small exposures. The pink and grey colored volcanic rock&around aa.ova and ~ Vlll~ are snde6itic in cO",,06ition vnth hypocryWlUine-porphyritic to hyalopJitic texture, The phenocrysts are andesine. hornblende. pyroxene. biotite. quartz and opaque minelllls and the groundmass is glassy and ni(:rolil)c. Around Yenisehlr area, the IIOIeanlc rockS are dar')( ",ey and greeniSh grey In color and InelU6e plagloetase and pyrol(ene phenocrysts..While the main fetsic nineraI of the hypocrystat1in&-porphyriticvolcanic rocks is ~Iese. the main mafic is pyroxene involving in e microlitic g'oundm:a&S.However the rricrolites do not &how a el88r alignment, but some of them surround the phenocrysts. The volcanic rocks are ~y enriched in LIL elements and modcfately enriched in HFSE elements, One of the SiIImplefrom Sa;ova are. has yielded ArU)IAi~ age of 14,710,1 Ma, Another sample abOtlt 12 km to the SW, nearYenisehlr has dated as 14.3,tO.1 Ma, This suW:k.8·line and cere- alkaline volcanism is represented by lavas, dikes and pyroctaWcs In the region, These volvanic rocks in neany eeme ag86 and exposing in dose locefrties to 88Ch othet. have been OOIIsideredto be the prod1.Ict&of the same 9t8OUS actMty because their geochemical affinitie&.