ON THE ORE-BEARING METAMORPHIC ZONE OF A CERTAIN SKARN TYPE OF ORE DEPOSIT OF HOPEI

In this ore deposit of skarn type,several approximately parallel metamorphic zoneswere noticed between Sinian dolomite and Yenshan porphyritic granite,which belongs toa branch of a great igneous intrusion.There is a certain rule in such zonal distribution.All the rocks in the contact zones,including those in the immediate approximate parts ofthe intrusive,have been metamorphosed to various extent. Four kinds of metamorphic zones are revealed in the chronological order namely(1)purely thermal metamorphic zone,(2) metasomatic contact metamorphic zone,(3) ser-pentinized zone and (4) ore-bearing hydrothermal alteration zone. Chemical analyses of granite and rock samples of various metamorphic zone aregiven in tables as evidences to explain development of different metamorphic zone es-pecially for (1) and (2) zones.