Geochemical and zircon geochronological study on the meta-mélange belt in the Kokchetav region (North Kazakhstan): Implications for the early Cambrian to early Ordovician seamount accretion

The manuscript deals with the zircon U-Pb geochronology data (Supplementary table 1), Whole-rock major-trace geochemistry data (Supplementary table 2) and Whole-rock Nd isotopic geochemistry data (Supplementary table 2) of Kokchetav meta-mélange belt in the western Altaids (North Kazakhstan). A new tectonic evolution model concerning subduction and exhumation of the HP/UHP metamorphic rocks has been proposed according to these data, which sheds light on a better understanding the tectonic evolution of the North Kazakhstan before its bending to form the Kazakhstan orocline, as well as the paleogeography in the western Altaids.
Among them, Supplementary table 1: Whole-rock major and trace element data from the Kokchetav accretionary complex;
Supplementary table 2: LA-ICP-MS U-Pb data of themetamafic/metasedimentary samples from the Kumdy-kol region of the Kokchetav accretionary complex; Age discordance is reported by (207Pb/235U age)/(206Pb/238U age)*100 if 206Pb/238U age is <1000 Ma, otherwise by (207Pb/206Pb age)/(206Pb/238U age)*100, if older. Ages with discordance between 90 and 100 were determined by 206Pb/238U, if younger than 1000 Ma, otherwise by 207Pb/206Pb age, if older. The results with discordance greater than 10% are marked. Detailed analytical method of zircon U-Pb dating is presented in the main text.
Supplementary table 3:Whole-rock Sm-Nd isotope analyses data of the metamafic/mafic rocks from the Kokchetav accretionary complex; Detailed analytical method of zircon U-Pb dating is presented in the main text.

本手稿涉及阿尔泰造山带（Altaids）西段北哈萨克斯坦境内的科克切塔夫变质混杂岩带的锆石U-Pb年代学数据（补充表1）、全岩主量-微量元素地球化学数据（补充表2）以及全岩Nd同位素地球化学数据（补充表2）。基于上述数据，本文提出了一套全新的针对高压/超高压（HP/UHP）变质岩俯冲折返过程的构造演化模型，为深入理解北哈萨克斯坦在弯曲形成哈萨克斯坦构造结之前的构造演化历史，以及阿尔泰造山带西段的古地理格局提供了新的认知。

其中，补充表1：科克切塔夫增生杂岩的全岩主量与微量元素数据；
补充表2：科克切塔夫增生杂岩昆迪科尔（Kumdy-kol）地区变基性/变沉积岩样品的激光剥蚀电感耦合等离子体质谱（LA-ICP-MS）U-Pb数据；年龄不一致度计算规则如下：当206Pb/238U年龄小于1000 Ma时，以(207Pb/235U年龄)/(206Pb/238U年龄)*100计算；若年龄大于1000 Ma，则以(207Pb/206Pb年龄)/(206Pb/238U年龄)*100计算。不一致度介于90~100之间的年龄，若小于1000 Ma则采用206Pb/238U年龄，若大于1000 Ma则采用207Pb/206Pb年龄。不一致度大于10%的测试结果予以标注。锆石U-Pb定年的详细分析方法见正文。

补充表3：科克切塔夫增生杂岩中变基性/基性岩的全岩Sm-Nd同位素分析数据；锆石U-Pb定年的详细分析方法见正文。