8 1null72 0 0 7M7null nullnullnullnullnull null ACTA GEOLOGICA SINICA null nullVol.81 null No.7July null 2 0 0 7:SE1S(I|40573025)Tbl: 2007null05null18;: 2007null06null22;3I :ySbTe:W+,3, 1956M3b,pV3=,VY5obY: 100037,v26|;: 010null 68999042; Email: nfjj mx. cei. gov. cnb=l5nullM-#il聂凤军1) , 张万益1) , 杜安道2) , 江思宏1) , 刘妍1)1)SS, 100037; null 2)SELk, 100037=41:Bl5HW,186qnulls,HLM-135.5null 1. 5Ma( 2null) ,MSWD1.4bkvvs,iOFKF31,Vwlu5HW(*,/nullb1oM:nullM-;H;5;l;=null nulll98(/e8)=TS20W70M, 1971M1982MW,a8=uu7ZV1:20u,iO4M3;1980M1983MW,8v(8-&)=ovTuV1:5sT,iOBvaa#as;1982M1983MW,8vlu1osd7aG(a)T,5?C19H8; 2004M,=-8dT,F4153,3. 3,5cMS0. 037% 0. 112%,(c0. 09%bVTV,l58a(aaFsa07Hqz+,z7?-nullb-T$,l57ZdaoM,Ha),y58T,5s4SGb1 nulll5d:nulld+*3/null,25km)duvnull!v(m1)b14#,sv43_/F/Y,l5#?null|3_(8)n,1=dM0FF#dXh4pFnull(uB,1994;=1u, 1991;#,1991) nullbM0Fnull1slu,u(8)50%P,1Faaa%aYbFnull1ua2,u(8)30%Pb1FaanullabF/M0F(1b=dnullM1,dXh4pF,su2b1Fg%a,*/=dnull(1bsu)!,rFbluS=+?S8s92005I)Fig. 1 null Simplified geological map of the Xiaodonggouporphyry molybdenum deposit, Hexigten Qi, InnerMongoliaand the insert showing its tectoniclocality (afterTianjin Geological Survey of North China Bureau ofGeology and Exploration, 2005)1null; 2null=dFnull; 3nulll; 4null; 5null; 6nullvL; 7null-eWv; 8null8; 9null; 10null(E); 11null)g; 12nulll5;null nulld; null null3/null; nullnulluv1null Quaternary; 2null Upper Permian volcanonullsedimentary rocks ofthe Randifang Group; 3null Xiaodonggou porphyritic biotite granitestock; 4null biotite granitoid hybrid; 5null fault; 6null suture zone; 7nullPrecambrian metamorphicblock; 8null molybdeuum orebodies; 9nullbiotite hornfels zone; 10null location of county government; 11nulllocation of prefecture government; 12null Xaiodonggoumolybdenium deposit. null null northern China craton; nullnull Paleozoictectononullmagmatic belt; null null Siberian plates,z+E,_MUC,81/5bV%null,a%,v/b1KF(HFa|FaF) (c35% 45%);|F( 20% 25%),F( 30% 35%)(1% 3%)bFaFaFFb5MHM%/iBY,21c+1Es,iAYb22qSiO2c73. 43% 77. 65%,8997null null null null null null null nullW+:=l5nullM-#il(75. 12%;aFs( K2O+ Na2O)c8.32% 9. 48%,(8. 75%; K2O/Na2 O11. 05 1.76,(1. 28;