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沿朱诺金矿带分布的中温热液含金石英脉矿床，是早第三纪由低金度、富H2O－CO2（±N2、H2S、CH4），温度为200～325℃，压力超过（1～1．5）×108Pa的流体形成的。同位素重的成矿流体，其δ18O为＋8‰～＋12‰，δD值为－20‰～－30‰，表明为深部流体源。这些数据与阿拉斯加南部大陆边缘下面的俯冲物质经过变质去挥发份作用形成成矿流体的模式一致。进变质流体渗入由于海岸山脉巨型区域断裂线而提高了渗透性的区域，然后在更高的退变质地壳层位的脆弱带形成含金脉。金的沉淀，是由包括沸腾、流体－围岩反应，以及热液流体的温度、压力下降等几种机制完成的。
The middle-temperature hydrothermal gold-bearing quartz vein deposits distributed along the Juno gold belt are characterized by low gold content, rich in H2O-CO2 (± N2, H2S, CH4) and a temperature of 200-325 ℃ in the early Tertiary. (1 to 1.5) x 108 Pa. Δ18O is +8 ‰ ~ +12 ‰ and δD is -20 ‰ ~ -30 ‰, indicating a deep fluid source. These data are consistent with the pattern of metamorphosed devolatilization of subducted matter beneath the margins of southern Alaska to form ore-forming fluids. Metamorphic fluids infiltrate regions of increased permeability due to the fault line of the mega-region of the Coastal Mountains and then form a gold-bearing vein at the vulnerable zone of the higher degenerated texture crust. The precipitation of gold is accomplished by several mechanisms, including boiling, fluid-surrounding rock reactions, and the temperature and pressure drop of hydrothermal fluids.