The Chaldoran ophiolite in NW Iran and at the Turkish border is a part of the larger Khoy ophiolite. Serpentinized peridotites, pillow basalt, cumulate and isotropic gabbro, pelagic limestone, and radiolarite along with volcano‐sedimentary units are the main rock types in the area. These rocks are mixed together in some places as tectonic and “coloured” mélanges. The gabbro consituent of this ophiolite is either fresh or is metamorphosed up to upper greenschist facies. These meta‐basic rocks contain relatively large crystals of plagioclase and clinopyroxene, partially changed to amphibole. Metamorphic epidote is formed in some samples. Whole‐rock chemistry of these rocks shows a basaltic magmatic composition. Low SiO₂ contents along with relatively high MgO and FeO_total contents testify for a mantle source for the parental magma of the studied samples, intermediate between tholeiitic and calc‐alkaline series. LREE and HFSE are slightly depleted and LILE show enrichment in the studied samples and Ta, Nb, Ti show negative anomalies with respect to MORBs. All chemical features are compatible with a supra‐subduction zone setting for the rocks. The studied rocks are similar to primitive arc and less evolved rocks, geochemically. Also the samples show both MORB‐like magmas, formed at the initial stage of a subduction and IAT chemical features. U–Pb dating of zircons on the gabbro sample gave 107.5 ± 1.3 Ma (Albian) crystallization age. The metabasites from the Chaldoran ophiolite are similar to intra‐oceanic ophiolite‐related igneous rocks from the Zagros suture zone in Iran and NE Iraq and equivalent rocks from the Neotethyan sutures in east Turkey and Armenia and basic rocks from the Late Cretaceous ophiolites of the outer Zagros and Taurus, which are related to the subduction initiation (SI) stage.

中文翻译：

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伊朗西北部新特提斯北部分支的早白垩世（阿尔比亚）洋内俯冲：查尔多兰地区的锆石U–Pb年代学和脂生变质的地球化学

伊朗西北部和土耳其边境的Chaldoran蛇绿岩是较大的Khoy蛇绿岩的一部分。蛇纹岩橄榄岩，枕形玄武岩，累积和各向同性的辉长岩，​​上层石灰岩和放射性云母以及火山沉积单元是该地区的主要岩石类型。这些岩石在某些地方混杂在一起，形成构造和“彩色”混杂岩。该蛇绿岩的辉长岩成分是新鲜的，或变质到上层绿片岩相。这些准基性岩石含有斜长石和斜辉石的相对较大的晶体，部分变为闪石。在一些样品中形成了变质的附子。这些岩石的全岩石化学性质显示出玄武岩的岩浆成分。较低的SiO ₂含量以及相对较高的MgO和FeO_总量含量证明了所研究样品的父母岩浆的地幔源，介于生高岩和钙碱性系列之间。LREE和HFSE略微耗尽，LILE在所研究的样品中富集，而Ta，Nb，Ti相对于MORB呈负异常。所有化学特征均与岩石的超俯冲带设置兼容。所研究的岩石在地球化学方面类似于原始弧，而演化程度较小的岩石。样品还显示了俯冲初期形成的MORB样岩浆和IAT化学特征。长辉石样品上锆石的U–Pb测年给出了107.5±1.3 Ma（Albian）的结晶年龄。