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朱诺金矿带中的含金石英脉系分布于阿拉斯加海岸山脉西部边缘一个长约160km、宽约5～8km的地带内。矿脉赋存于邻近岩带边界中白垩纪逆冲式剪切带内。据大量矿脉方位和剪切方向资料分析确定的应力特征为:最大主应力轴为NE—SW走向,近于水平,最小主应力轴近于垂直。这种局部应力特征与始新世远场板块的应力特征是一致的。矿脉形成的同位素年龄指示,流体发生循环的时代介于56.5～52.8Ma之间,说明矿脉形成与早始新世板块运动的变化有成因联系的结论一致。同时,成脉作用与较晚期的快速剥露作用和紧邻金矿带侧面的深成侵入活动是同步发生的。作者提出以下模式:相互作用的构造事件促进了断层阀的活动,并导致矿脉沿着现已剥露的剪切带发育。
The gold-bearing quartz veins in the Juno gold belt are distributed in a strip about 160 km long and 5 ~ 8 km wide at the western edge of the Alaskan Coastal Mountains. The veins occur in Cretaceous thrust shear zones in the adjacent lithosphere boundaries. According to a large number of veins and shear direction data analysis to determine the stress characteristics: the maximum principal stress axis is NE-SW direction, near the level, the minimum principal stress axis near vertical. This local stress feature is consistent with the stress characteristics of the Eocene far-field plate. The isotopic ages of the veins indicate that the age of fluid circulation ranges from 56.5 to 52.8 Ma, indicating that the formation of the veins is in line with the genetic association of the changes of the Early Eocene plate movement. At the same time, the vein-forming effect coincides with the later rapid tearing-off and the deep-penetrating intrusion on the side of the gold belt. The authors propose the following model: Interaction of tectonic events facilitates the movement of the fault valve and leads to the development of veins along the now exposed shear zones.