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| COMPARISON OF GOLD DEPOSITS BETWEEN NORTH CHINA AND WESTERN AUSTRALIA CRATONS AND ITS GUIDANCE TO GOLD EXPLORATION IN CHINA |
| Luo Zhenkuan, Miao Laicheng, Guan Kang, Huang Jiazhan |
| Tianjin Geological Academy, MMI |
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Abstract North China craton is a later-solidified and more active craton,from which more than 50% gold of China is mined.Ore-host rocks are mainly meso-hypometamorphic mafic rocks and granitoid.Large-cale gold deposits accour in the superimposed structural zones of ductile and brittle shearing.Granitoid rocks are broadly distributed in the craton.Ore bodies are in stratiform,lens,veins or pipes.Most of them are large quartz vein type.Mineral compositions are chiefly guartz,sericite,K-feldspar and pyrite.Au is associated with Cu,Pb,Zn,Ag,W,S,As,Bi and Sb.Wall-rock alteration types indude silicification,sericitization,pyritization,K-feldspathization,carbonation and chloritization.The mineralization age is 188~46Ma.
Western Australia craton is an earlier-solidified and stable one.Almost 70% gold of the continent comes from W.A.Most gold deposits occur in Archeozoic granite-greenstone terrains of Yilgarn block.Structurally,major deposits are distributed in the fransitional or superimposed zones of ductile brittle shearing.Granitoid rocks occupy Yilgarn block by 2/3 area.The occurences of ore bodies in W.A.craton have no difference from those in N.China craton.Shear zonal and metasamatic types of deposits are dominated in W.A.Main minerals in ore are quartz,sericite,albite,chlorite,amphibole,carbonate,pyrite and arsenopyrite.Alteration types include pyritization,silicification,sericitization,chloritization,carbonation,albitization and Cr-V-micatization-The mineralization age is 2640~2600Ma.
Comparing to its counterpart in W.A.craton,the mineralization in N.China craton is much later.The craton has undergone less denudation Many deposits have not outcropped.The exploration for gold in N China craton is promissing.
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Received: 23 September 1996
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1997, Vol. 6 
