Uranium and microcracks in a 1,000-meter core, Redstone, New Hampshire

摘要: The spatial distribution and mineralogical association of uranium in 30 samples a 1,000 meter core from the Redstone (NH) Quarry were examined with fission track techniques, backscattered electron imaging, energy dispersive X-ray spectrometry following results for Conway Mount Osceola granites: (1) Uranium occurs microcracks sealed siderite and/or Ca+ RE fluorocarbonate minerals; contents fluorocarbonates are 1 to ppm 500–1,500 ppm, respectively. (2) Siderite lesser extent minerals occur as replacement amphibole biotite; main alteration allanite. (3) degree redistribution greater major uraniferous microcracks. (4) Ca Mn approximately constant cracks throughout granites entire section penetrated by corehole, 700 meters. — From these observations, we conclude that an extensive set fractures significant volume granties conduits through which hydrothermal fluids containing CO2, uranium, REs circulated. Microcracks facilitated fluid-rock interactions resulting redistribution. Certain primary accessory minerals, i.e., allanite ilmenorutile may have been source at least part now secondary granites.