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朱诺金矿带的中温热液含金石英脉在早第三纪时在温度为200～325℃,压力大于1—1.5千巴富含H_2O-CO-2(±N_2、H_2S、CH_4),低盐度的流体中形成。成矿流体富重同位素,其δ~18O在+8‰至+12‰之间,δD在-20‰至-30‰之间,表明了流体的深成来源。这些数据与俯冲于南阿拉斯加大陆之下的物质经过变质脱挥发份作用形成成矿流体的模式是一致的。前进变质作用形成的流体向上渗透到与海岸巨型线性构造共生的由机械作用而增加渗透度的各带中,并在较高处的退化变质的脆性岩石中形成含金矿脉。金的沉淀是通过若干机制完成的,包括沸腾、流体与围岩友应、以及热液流体的温度压力下降等。
In the early Tertiary, the gold-bearing quartz veins of the mid-temperature hydrothermal gold in the Juno gold belt were at 200-325 ℃ and the pressure was higher than 1-1.5 kPa, which was rich in H_2O-CO-2 (± N_2, H_2S, CH_4) , Low salinity fluid formation. The isotopic compositions of the ore-forming fluids are δ ~ 18O between + 8 ‰ and + 12 ‰ and δD between -20 ‰ and -30 ‰, indicating a deep source of fluids. These data are consistent with the pattern of ore-forming fluids that have undergone metamorphic devolatilization subducted beneath the South Alaska continent. The fluids formed by the advancing metamorphism penetrate upwards into zones that are mechanically interpenetrating up with the giant linear structures of the coast and form gold-bearing veins in the degraded, brittle rocks at higher levels. Gold precipitation is accomplished through a number of mechanisms, including boiling, fluid and surrounding rock companions, and the temperature and pressure drop of hydrothermal fluids.