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对取自302铀矿床井下与沥青铀矿矿石共生的9件紫黑色萤石、肉红色方解石样品进行了流体包裹体的He同位素测定,3He/4He测定值为0.03～0.57 Ra(绝大部分在0.11～0.25 Ra之间),位于地幔与地壳的氦同位素值范围之间,显示成矿流体中的氦同位素具有壳、幔两个端元混合的特点,表明有大量幔源挥发性组分参与铀成矿作用。该矿床碳同位素值与流体包裹体证据均表明,地幔挥发性组分确实大规模参与了铀成矿作用。研究显示,几乎华南所有的热液铀矿床都形成于白垩纪—古近纪,且这些矿床的碳同位素组成均显示成矿流体中的矿化剂CO2来自地幔,暗示它们成矿时具有相似的成矿动力学背景:可能均与华南中-新生代岩石圈伸展作用所控制的幔源挥发性组分具有密切的关系。
He isotopes of fluid inclusions were measured for nine purple-black fluorite and meat-red calcite samples taken from the co-exited pit 302 with uraninite ore, with a 3He / 4He of 0.03-0.57 Ra (the vast majority of 0.11 ~ 0.25 Ra) located between the range of helium isotopic values of the mantle and the crust, indicating that the helium isotopes in the ore-forming fluids have the characteristics of the mixing of two end units of crust and mantle, indicating that a large amount of mantle-derived volatile components are involved Uranium mineralization. The carbon isotope values of the deposit and the evidence of fluid inclusions show that the mantle volatile components are indeed involved in uranium metallogenesis on a large scale. Studies have shown that almost all hydrothermal uranium deposits in southern China were formed during the Cretaceous-Paleogene and that the carbon isotopic compositions of these deposits show that the mineralizing agents CO2 in the ore-forming fluid are derived from the mantle, suggesting that they have similar Metallogenic kinetic background: It may be closely related to the mantle-derived volatile components controlled by the Meso-Cenozoic lithospheric extension in South China.