The Paleo-interlayer Oxidation and the Paleointerlayer Oxidation Type Uranium Mineralization in the North Area of Qaidam Basin

The paleo-interlayer oxidation is an interlayer oxidation that it formed at a certain stage of basin geological tectonic evolution process.The uranium deposit formed and preserved by this interlayer oxidation is called paleo-interlayer oxidation zone type uranium deposit.Middle-lower Jurassic coal-bearing rock series grown widely for paleo-interlayer oxidation forming and relevant type uranium mineralization growing founded basis.Badly uplift denudation at early Cretaceous period late-stage to Palaeogene period early-stage is the formation period of interlayer oxidation zone and relevant type uranium mineralization.Large-scale reverse thrust tectonic causes interlayer oxidation zone and relevant type metallogenic system have been altered badly,paleo-interlayer oxidation zone and relevant type uranium mineralization formed and preserved.On the basis of its difference of alteration,destroy and conservation,the paleo-interlayer oxidation type sandstone-hosted uranium mineralization can be divided into 3 sub-type:folding-downed conserved,folded-faulting conserved and structure-uplifted destroy sub-type.The folding-downed conserved and folded-faulting conserved two sub-type cause paleo-interlayer oxidation zone sandstone uranium ore body can conserve well for blind ore,which is a key prospecting direction in future,its example are Beidatan and Lenghu Shide 26 uranium ore spot.Structure-uplifted destroy sub-type cause paleo-interlayer oxidation zone sandstone uranium ore body shows residual state or denuded.On the base of geological structural feature and prospecting criteria of different reformation subtype,and then synthetically analyzed its metallogenc characteristics,the metallogenic model of typical paleo-interlayer oxidation type sandstone-hosed uranium mineralization is established.