Tectonic Altered Rock Mapping And Resource Forecast Of Jiaojia Gold Ore-field

The Jiaojia ore-field, located in the northwest of Jiaodong Peninsular, ShandongProvince, is one of the most important gold production base in China, theworld-famous "Jiaojia Style" gold deposit was found here in the1970s. Several largegold deposit distributed on this region.Former studies have shown that the formationof these gold deposits are closely associated with the role of metasomaticalteration.However, most previous studies have focused on the range of tens of metersinside and outside of granite contact zone, the research of characteristics and laws forthe weak alteration zone within a few hundred meters from the orebody need to bestrengthened.During my graduate stage,I participated in several research of gold deposit.after alot of field work,I accumulated a wealth of measured data. On the basis ofcomprehensive in previous research achievement, after in-depth comparison andresearch, I completed my master’s degree thesis on schedule. Main conclusionsobtained are as follows:1. Explore and mapping altered rock distribution of Jiaojia ore field. Add weakK-feldspar altered granite in altered rock band for the first time, largely expanding thescale and scope of altered rocks. Mapping showed that the width of the alteration zonecan reach over1000m. The size of the alteration zone is directly related to the scale ofdeposit,the width of Jiaojia-Jinghuashan alteration zone can be up to3km,but thesouth section of Jiaojia fault which region does not developed alteration zone have notfound the gold deposit of scale.2．After the measurement and research, the distribution of alteration rockdetermines the type of deposit. For example, in the gold deposit of altered rock type,the scale of strong potassic alteration zone is larger than the scale of weak potassicalteration zone, in the gold deposit of quartz vein type, the scale of strong potassicalteration zone is smaller than the scale of weak potassic alteration zone.3. Geochemical tests of the altered rock band shows that in the gold deposit ofaltered rock type, SiO2、CaO、Na2O、TiO2、Rb、Ta、Ce moved in. In the gold deposit of quartz vein type, Na2O、K2O、TiO2、BaO、Rb、Ta、Ce moved in. The comparisonof different stages of alteration found that the phyllic alteration phase is the mainstage of elements enrichment.4. Calculated each alteration zone rocks with the CIPW method, mineralalteration zones established for each sectional shows, in the gold deposit of alteredrock type, the main course is feldspar alteration and silicification,in the gold depositof quartz vein type, the main course is silicification and decalcification.5. The first attempt to predict the amount of gold ore through altered rocks, theforecast of Jiaojia gold ore-field shows that gold metal content of phyllic alterationzone is approximately715t, gold metal content of strong potassic alteration zone isabout978.8t.