The Mesozoic Alaska Range suture zone is defined by a transition from oceanic to continental terranes and is part of a 2000‐km‐long tectonic boundary throughout the northern Cordillera. Surface geologic mapping of the rock types across this suture zone provides critical information about the upper crustal configuration but provides little insight into the sedimentary, igneous, and metamorphic processes that occurred in deeper levels of the collisional zone. To better constrain the timing and mantle‐crust sources of collision‐related magmatism, we combine U‐Pb ages and Hf isotope compositions of detrital zircons from the three main components of the suture zone. U‐Pb/Hf data sets from inboard, continental margin samples have Precambrian‐Paleozoic ages with epsilon Hf_(t) values ranging between +10 and −20. U‐Pb/Hf data sets from the outboard, oceanic terrane samples have Pennsylvanian‐Permian detrital zircon ages with epsilon Hf_(t) values between +16 and +10. The U‐Pb/Hf data set of detrital zircons from Mesozoic strata that represent intervening sedimentary basin(s) that formed between the continental margin and oceanic terranes record Precambrian‐Mesozoic detrital zircon ages with epsilon Hf_(t) values between +14 and −20. Results of the study document four Archean and Proterozoic global crustal magmatic events that are correlated to the tectonic growth of Laurentia. Also, three Phanerozoic magmatic events have been identified that represent more regional tectonic events. This study demonstrates that the combination of U‐Pb geochronology and Hf isotope geochemistry applied to detrital zircons is a powerful tool to define sediment provenance in collisional zones and delineate episodes of global and regional magmatism along convergent plate boundaries.

中文翻译：

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中生代阿拉斯加山脉缝合带（阿拉斯加中南部）的地质，U-Pb地球年代学和Hf同位素地球化学：对北美山脉山脉碰撞过程和构造增长的影响

中生代阿拉斯加山脉缝合带是由从海洋到大陆的过渡所定义的，并且是整个北部山脉的2000公里长的构造边界的一部分。横跨该缝合线区域的岩石类型的表面地质图提供了有关上地壳构造的关键信息，但对碰撞区域深处发生的沉积，火成岩和变质过程了解甚少。为了更好地限制与碰撞有关的岩浆作用的时间和地幔源，我们结合了U-Pb年龄和碎屑锆石的Hf同位素组成，这些成分来自缝合带的三个主要部分。来自内侧大陆边缘样品的U-Pb / Hf数据集具有前寒武纪-古生代时代的εHf _（t）值介于+10和-20之间。外侧海洋样本的U‐Pb / Hf数据集具有宾夕法尼亚州的二叠纪碎屑锆石年龄，εHf _（t）值在+16到+10之间。中生代地层碎屑锆石的U-Pb / Hf数据集代表了大陆边缘和海洋地层之间形成的中间沉积盆地，记录了前寒武纪-中生代碎屑锆石年龄和εHf _（t）值介于+14和-20之间。该研究结果记录了四个与Laurentia构造增长相关的太古代和元古代的地壳岩浆事件。此外，已经确定了三个代表代区域性构造事件的多生代岩浆事件。这项研究表明，将U-Pb年代学和Hf同位素地球化学相结合应用于碎屑锆石是确定碰撞带沉积物出处并描绘出沿汇聚板块边界的全球和区域岩浆活动的有力工具。