Furthermore, the chondrite-normalized rare earth element (REE) patterns show an LREE enrichment with no clear Eu anomaly. The negative Nb, Ta, and Ti anomalies and large ion lithophile element (LILE Rb, Ba, and Sr) enrichments relative to primitive mantle indicate a subduction setting. The amphibole-plagioclase thermometer and Al-in-hornblende barometer data yielded crystallization temperatures of 707–899☌ and pressures of 0.5 to 2.9 kbar. The compositions of biotite, clinopyroxene, and amphibole as well as whole rock chemistry of the Andarian volcanic rocks show calc-alkaline signatures. The basaltic andesite and hornblende andesite are mainly comprised of K-feldspar (Or 10-63), plagioclase (An 5-37), calcic amphibole, clinopyroxene (En 45-64 Wo 29-54 Fs 0-20), and biotite (Mg#: 0.70–0.82). These units are composed of a series of intermediate to acidic volcanic rocks including basaltic andesite, hornblende andesite, andesite, dacite, and rhyodacite. The Neogene Andarian volcanic rocks, a part of the Ahar-Arasbaran magmatic zone, are situated in the northwest of Iran.
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