| Liangcheng-Jining area is located in the eastern part of Wulashan-Daqingshan districtwhich is one of the most important gold, silver and polymetallic metallogenic province in China.The area is also part of Mesozoic volcanic belt in eastern China. Based on the project of "themetallogenic regularity and exploration direction of gold-silver in Wulashan-Daqingshandistrict", the metallogenic condition and metallogenic model of gold-silver polymetallicmetallogenic deposit in Liangcheng-Jining district were studied in this thesis, mineralizationtarget were forecasted by means of the integrated methods of geology-geochemistry-geophysics in the favorable mineralization area.The thesis studied metallogenic conditions and mineralization of Liangcheng-Jiningdistrict firstly. Based on study of metallogenic conditions of Liqingdi silver deposit andJiulongwan silver deposit, including fluid inclusions and isotopes of lead, sulfur and Hydrogen-Oxygen., it came to the conclusion that mineralization of Liqingdi silver deposit andJiulongwan silver deposit is probably related to annular and radial faults of volcanic apparatus.Their metallogenic materials may be deep source. The ore-forming fluids could be middle-lowtemperature, their average temperature250℃and270℃respectively, low density that Liqingdiis from0.65g/cm3to0.90g/cm3and Jiulongwan from0.75g/cm3to1.0g/cm3, brine system thatLiqingdi salinities is from1.74wt％to10.73wt％and Jiulongwan from3.1wt％to5.7wt％. The atmospheric water that theδ18O and δDH2O‰(SMOW) values is6.4～13.57‰and-97.28～-62.29‰respectively may participate the ore-forming processes of the two deposits.The genesis of the deposits thought to be hydrothermal deposit which is related to continentalvolcanic and sub-volcanic rocks.This thesis studied emphatically volcanic and sub-volcanic rocks related to silver-polymetallic deposits. Also proved that Jurassic metallogenic related volcanic rocks ofLuotuoshan and Naobaoshan maybe all have similar features based the study on the comparesof rock geochemistry, trace elements, REE and formation environment of volcanic rocks. Theyall could be calc-alkaline acid rocks and were in orogenic belt environment. Similar chemicalcompositions and chemical features of volcanic rocks of Luotuoshan and Naobaoshan mayindicate that there could be great possibility to form new deposits around Luotuoshan volcanite.Based on the above results, the mineralizing model was established and prospectingcriteria have been presented. The evolvement of Mesozoic North China lithosphere was veryactive,which undergone such three geodynamics events as collision orogeny occurring, tectonic system transferring and the scaled lithosphere dismantling and sinking, therefore, continentalvolcanic rock, sub–volcanic rock and related deposits which are connected with Silverpolymetallic deposit are formed. In addition, according to mineralizing rule and modelestablished, prospecting criteria with volcano tectonics and geochemistry and alteration werealso presented.Finally, the metallogenic prognosis and ore prospecting direction in Luotuoshan area wascarried out in this thesis. It showed that this area belonged to the most possible metallogenicabnormal area of1:50000stream sediment survey taking on the high abnormity value of Ag, Sb,Bi, Pb. Besides, it was also showed that there was enriched such elements as Bi, Sb, Pb in theabnormal area of volcanic rock, which is identical to the results of multivariate statisticalanalysis. Then,1:10000geological mapping and1:5000primary halo surveying as well as1:10000geophysical prospecting were performed, and three potential mineralization target weresuggested, and of the two suggested by geological exploration were corresponding withgeophysical prospecting. In general, the main conclusions of this thesis have a good theory andpracticing guidance for the geological exploration of this region.
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