| Dasongshu gold deposit which is about 9 km away from the northwest ofWeishahe town is located in the southeast of Laoling metallogenic belt. It has beenlocated active continental marginal belt continental margin since Mesozoic.Northeast anticlinorium formed at early stage because of extrusion, while Laolingmetamorphic core complex stuctural system formed at late stage.The main strata and mineralizing host rock of the ore field are thick layer ofdolomitic marble which included hornblende schist and biotite quartz schist in lateProterozoic Era Zhenzhumen formation Laoling group. They striked northeast anddipped northwest as a whole. The skarn rock belt lied in the contact belt betweenLishugou rock body and mineralizing host rock.The ore field is located on metamorphic core complex detachment zone. Aseries of secondary fracture belts developed and paralleled main detachment zone.The detachment zone is multiperiod active. The physical nature of marble inZhenzhumen group showed brittleness and developed brokenly among layers. Thedetachment zone controlled the distribution of ore bodies. There are manyNorthwest fractures which formed later and are brittle. The most beneficial part ofmetallogenic is the joint between NE and NW fracture.Lishugou activity has close relations with the forming of gold deposit inYanshan Era. The metallogenic process of magmatism supplied heat, material andfluid for the deposit. Ore bodies are located in the contact of inner and outer of rockbodies, their forming time are after that of the intruding of the rock bodies (1# dykecut rock bodies ) .The mineral component of Dasongshu gold deposit is simple, metal mineralcomponent is between 2% and 5%, and the component of pyrite is the highest,which is in direct interrelation with the component of gold. A set of epithermalalteration such as silication, pyritization, carbonation and sericitation has closerelations with the gold deposit.The average temperature of fluid inclusions is 221℃ average through theexamination of fluid inclusions analysis in quartz vein, which showed thetemperature of metallogenic fluid is middle and low temperature mostly. Theaverage metallogenic pressure is 60. 3 Mpa and the average metallogenic depth is 6.18 km, which reflected the metallogenic environment in middle depth. thecharacteristic of metallogenic fluid is low salinity (average value is 5.15wt%NaCl) , low density (average density is 0. 79g/cm3) , which is because of themixture of meteoric water and leads to multistage of metallogenesis.Therefore, the author considers that Dasongshu gold deposit is epi-meso-thermal gold deposit which is controlled by structure and has relations withmagmatic activity.The author established an synthetic model of exploration information based ongeological information, geophysical and geochemical information, according tounderstanding of previous achievement research and analyses to the informationfrom geology, geophysics and geochemistry. Finally, the author evaluated andforecasted the deposit too.The bigger concealed ore bodies may be found beneath the Dasongshu golddeposite basing on the controlling characteristics of detachment tectonics andsynthetic exploration information.The synthetic exploration information in Liujiatangzi gold occurrence whichis the west extending proportion of Dasongshu mineralizing-alterating belt issimilar to those of the Dasongshu gold deposit through evaluating the outer area'starget of the deposit. The metallogenic conditions and the ore prospecting of thearea between the two parts are well. The scale of Dasongshu gold deposit may beenlarged through carrying out integrated exploration in the contact belt.In all, the metallogenic condition of the Dasongshu gold deposit is well, andthe erosion of the deposit is not deep, and the deposit was conserved well. So, thepotential of exploration is great in the depth and outer.
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