The Eocene felsic stock and dike swarm with intermediate composition from Central Iran (southwest of Jandaq) are studied to understand geodynamic evolution of the Central-East Iranian Microcontinent (CEIM). Field relationships show that the dikes, composed of trachyandesite and basaltic trachyandesite, cross-cut the felsic stock. Whole rock geochemical data reveal the calc-alkaline nature of stock and high-K calc-alkaline to shoshonitic nature of dikes. The felsic stock and intermediate dikes show LREE and LILE enrichment and HFSE (Ta, Nb and Ti) depletion, suggesting that they probably formed in a subduction zone and are similar to the volcanic arc rocks. The rock samples of felsic stock have geochemical characteristics of the high silica adakites (HSA) produced by melting of a subducted oceanic crust. On the other hand, the dikes have characteristics of low silica adakites (LSA) produced by partial melting of a lithospheric mantle peridotite previously metasomatized by slab-derived melts. The Eocene felsic stock and dikes probably formed by subduction of the CEIM-confining oceanic crusts beneath the CEIM. The field and geochemical studies indicate that the magma originated from melting of basic section (amphibolite) of the subducted slab (HSA) will arrive to the Earth surface before the magma formed by melting of mantle wedge peridotites (LSA).

研究了来自伊朗中部（Jandaq西南）的始新世长岩和具有中间成分的堤防群，以了解伊朗中东部微洲（CEIM）的地球动力学演化。田间关系表明，由砂岩性和玄武岩性沙土组成的堤防横切了长茎类种群。整个岩石地球化学数据揭示了堤坝的钙碱性和高K钙碱性对堤防的粗化。长英质储层和中间堤防显示出LREE和LILE富集以及HFSE（Ta，Nb和Ti）耗竭，表明它们可能形成于俯冲带，与火山弧岩相似。长英质储层的岩石样品具有通过俯冲的洋壳融化而产生的高硅质Adakite（HSA）的地球化学特征。另一方面，这些堤坝具有低硅质红土的特征，该石质是由事先由板状熔体交代的岩石圈地幔橄榄岩的部分熔融而产生的。始新世长岩和堤防可能是由CEIM之下的CEIM限定洋壳俯冲所形成的。现场和地球化学研究表明，由俯冲板块基本剖面（闪石）融化形成的岩浆将在地幔楔形橄榄岩（LSA）融化形成的岩浆之前到达地球表面。