Geochronology of HP/LT rocks and amphibolites from the Hajiabad-Esfandagheh area, Sanandaj-Sirjan Zone, Iran

这项建议寻求为实地研究活动提供资金，这些活动旨在为伊朗萨南达伊-锡里扬地区Hajiabad-Esfandagheh地区混杂地区的HP/LT岩石和角闪岩建立坚实的地质年代学基础。现有的地质年代学数据库相对较小，不足以解开变质记录。为了评估以前报道的Ar-Ar数据的相关性，并获得更详细的变质演化图景，计划应用多方法地质年代学方法(Rb-Sr，Sm-ND，U-Pb)，该方法将改善古构造重建的年龄限制，并深入了解与阿拉伯和欧亚大陆汇聚有关的变质事件。重点将回答以下问题：(1)HP/LT岩石和斜长角闪岩记录的确切年龄是什么？(2)是否有任何区域年龄差异？(3)这些岩石是否与伊朗其他地方(如Makran地区)和/或阿曼暴露的类似事件在时间上相等？(4)在伊朗板块边缘更大的框架内，混杂岩的构造位置是什么？这些新数据将被用来建立更详细的古构造演化的时间框架，并有可能极大地促进对扎格罗斯造山带地球动力学演化的理解。

This proposal seeks funding for field-based research activities that aim at establishing a solid geochronologic foundation for HP/LT rocks and amphibolites from mélanges of the Hajiabad- Esfandagheh area, Sanandaj-Sirjan Zone, Iran. The available geochronological database is relatively small and insufficient to unravel the metamorphic record. In order to evaluate the relevance of previously reported Ar-Ar data and to obtain a more detailed picture of the metamorphic evolution, it is planned to apply a multimethod geochronological approach (Rb-Sr, Sm-Nd, U-Pb) that will provide improved age constraints for refinement of palintectonic reconstructions and in-depth understanding of the metamorphic events associated with convergence between Arabia and Eurasia. Emphasis will be placed on answering the following questions: (1) What are the exact ages recorded by the HP/LT rocks and the amphibolites? (2) Are there any regional age variations? (3) Are these rocks time-equivalent to similar occurrences exposed elsewhere in Iran (e.g. the Makran area) and/or Oman? (4) What is the structural position of the mélanges within the larger frame of the SW Iranian plate margin? The new data will be used to develop a more detailed temporal framework of the paleotectonic evolution and has the potential to advance significantly the understanding of the geodynamic evolution of the Zagros orogen.