Neoproterozoic-Early Paleozoic tectonic evolution of the western part of the Kyrgyz Ridge (Northern Tian Shan) caledonides

A comprehensive study of the western Kyrgyz Ridge reveals significant new insights into the Neoproterozoic-Early Paleozoic tectonic evolution of the Northern Tian Shan. Key findings include the identification of a diverse age spectrum spanning from the Neoproterozoic to the Early Ordovician for sedimentary units, the reconstruction and dating of Cambrian ophiolite complexes in suprasubduction settings, and the discovery of an Early-Middle Ordovician volcano-sedimentary complex with island-arc affinity. Additionally, the study confirms the widespread presence of Late Ordovician granitoids, some of which host Cu-Au-Mo ores. The research also elucidates the multi-stage thrust-and-fold structure formation from the Middle Cambrian to the Middle Ordovician, highlighting the critical role of the Early Ordovician stage and the intrusion of large batholiths in the early Late Ordovician, which marked the culmination of the Caledonide structural evolution. These findings suggest a prolonged and complex evolutionary history for the active continental margin.

Degtyarev, K. E., Ryazantsev, A. V., Tretyakov, A. A., Tolmacheva, T. Yu., Yakubchuk, A. S., Kotov, A. B., Salnikova, E. B., & Kovach, V. P. (2013). Neoproterozoic-Early Paleozoic tectonic evolution of the western part of the Kyrgyz Ridge (Northern Tian Shan) caledonides. Geotectonics, 47(6), 377–417. https://doi.org/10.1134/s0016852113070017