New geochemical and U-Pb isotopic data from the Torud volcanic and subvolcanic rocks and their associated dikes exposed along the southern margin of the Sabzevar-Torud zone provide new evidence for Early-Middle Eocene, post-collision magmatism in northeast Iran. The 52–46 Ma (late Ypresian-Lutetian) U-Pb age interval of zircons separated from these rocks confirm the paleontological age of nummulite-bearing limestone interlayers. Inherited zircons separated from these igneous rocks have a much wider range of U-Pb ages that include Archean, Paleoproterozoic, Mesoproterozoic, Carboniferous, Permian, Triassic, Middle Jurassic, and Late Cretaceous. Most volcanics and subvolcanic rocks display high-K calcalkaline and shoshonitic trends. Distinct crystal fractionation patterns of the volcanic and subvolcanic rocks suggest magmatic differentiation in separate magma chambers. The studied rocks, depleted in the HFSE and enriched in the LILE, display nearly homogeneous isotopic Sr (0.7039–0.7055) and Nd (0.5126–0.5129) ratios and positive ɛNd values (0.08–0.56) indicating partial melting from an enriched lithospheric mantle source that was slightly contaminated with crustal material. Fluids, especially those released from the subducted slab, affected the composition of the source for the studied rocks. The magmatism occurred in the Torud area after the Late Cretaceous-Paleocene collision of the Central Iran microcontinent and Binalud-Kopeh-Dagh blocks and the Early-Middle Eocene break-off of the subducted slab.

沿 Sabzevar-Torud 带南缘暴露的 Torud 火山岩和地下火山岩及其相关岩脉的新地球化学和 U-Pb 同位素数据为伊朗东北部早-中始新世、碰撞后岩浆作用提供了新证据。从这些岩石中分离出来的锆石的 52–46 Ma（伊普瑞斯晚期-卢特阶晚期）U-Pb 年龄区间证实了含铜镁石的石灰岩夹层的古生物年龄。从这些火成岩中分离出来的继承锆石具有更广泛的 U-Pb 年龄范围，包括太古代、古元古代、中元古代、石炭纪、二叠纪、三叠纪、中侏罗世和晚白垩世。大多数火山岩和次火山岩显示出高钾钙碱性和钾玄质趋势。火山岩和次火山岩的不同晶体分馏模式表明在不同的岩浆房中存在岩浆分异。所研究的岩石在 HFSE 中贫化并在 LILE 中富集，显示出几乎均匀的同位素 Sr (0.7039–0.7055) 和 Nd (0.5126–0.5129) 比率和正 εNd 值 (0.08–0.56)，表明来自富集的岩石圈地幔源的部分熔融被地壳物质轻微污染。流体，尤其是从俯冲板块中释放出来的流体，影响了所研究岩石的来源成分。伊朗中部微大陆与Binalud-Kopeh-Dagh地块晚白垩世-古新世碰撞和俯冲板片早-中始新世断裂后，Torud地区发生了岩浆作用。在 HFSE 中耗尽并在 LILE 中富集，显示出几乎均匀的同位素 Sr (0.7039–0.7055) 和 Nd (0.5126–0.5129) 比率和正的 εNd 值 (0.08–0.56) 表明来自略微污染的富集岩石圈地幔源的部分熔融与地壳物质。流体，尤其是从俯冲板块中释放出来的流体，影响了所研究岩石的来源成分。伊朗中部微大陆与Binalud-Kopeh-Dagh地块晚白垩世-古新世碰撞和俯冲板片早-中始新世断裂后，Torud地区发生了岩浆作用。在 HFSE 中耗尽并在 LILE 中富集，显示出几乎均匀的同位素 Sr (0.7039–0.7055) 和 Nd (0.5126–0.5129) 比率和正的 εNd 值 (0.08–0.56) 表明来自略微污染的富集岩石圈地幔源的部分熔融与地壳物质。流体，尤其是从俯冲板块中释放出来的流体，影响了所研究岩石的来源成分。伊朗中部微大陆与Binalud-Kopeh-Dagh地块晚白垩世-古新世碰撞和俯冲板片早-中始新世断裂后，Torud地区发生了岩浆作用。56) 表明部分熔融来自富集的岩石圈地幔源，该源被地壳物质轻微污染。流体，尤其是从俯冲板块中释放出来的流体，影响了所研究岩石的来源成分。伊朗中部微大陆与Binalud-Kopeh-Dagh地块晚白垩世-古新世碰撞和俯冲板片早-中始新世断裂后，Torud地区发生了岩浆作用。56) 表明部分熔融来自富集的岩石圈地幔源，该源被地壳物质轻微污染。流体，尤其是从俯冲板块中释放出来的流体，影响了所研究岩石的来源成分。伊朗中部微大陆与Binalud-Kopeh-Dagh地块晚白垩世-古新世碰撞和俯冲板片早-中始新世断裂后，Torud地区发生了岩浆作用。