Indication Of Geogas Prospecting Technology To Concealed Ore Body In Jiajika Rare Metal Orefield

Exploration of concealed ore has become a hot spot in the field of international exploration.In recent years,scientists have made many achievements in searching for the concealed deposits by deep-penetrating geochemistry methods.The geogas prospecting is widely concerned by geologists because of its simple operation,low cost,direct response to deep ore body information.Chinese scientists have done a lot of research on geogas prospecting,mainly focused on copper,gold ore bodies,rare metal concealed ore bodies have not been studied systematically.Jiajika diggings is one of the largest granite pegmatite rare metal rich areas in China.According to the analysis of geological conditions and metallogenic factors,there is still a great potential for ore exploration in the covered area.The research was conducted in Jiajika rare metal orefield.Geogas and aerosol particles were collected from X03,Shaotangou,54,528 and 26 ore bodies.By analyzing elements' content in geogas,the indicator of the technique to ore bodies was judged.And the pattern of indication,mechanism of the geogas prospecting,the optimization of sampling conditions were studied,and predicting the unknown rock mass.The results of experiment show that the geogas prospecting can indicate the concealed ore bodies of lithium,beryllium,niobium and tantalum,but it is poor for the 54 ore body,which is semi-concealed.And the mineralization type,scale,buried depth,occurrence of the ore body have an impact on pattern of geogas indication.By observing the aerosol particles with TEM,we found nano-sized metal particles in geogas,which are block,spherical,cylindrical.Their composition mainly is composite metal of Fe-Nb-Ta,similarly to the orebody.So the geogas anomaly is caused by deep orebody.Experimenting in Shaotangou ore body with shortening the pumping time,compared with the previous test,we found the content of each element in the geogas decreased commonly,but the indicating effect and the types of indicating elements didn't change significantly.We conducted an application experiment in Rixike,and set up the measuring-point in exploration line of the IP sounding.The results showed there is high content of geochemical blocks in the underground,which location is consistent with the IP sounding display abnormal area.And comparing above conclusion,it is speculated that this rock mass is likely to be a pegmatitic orebody containing niobium tantalum.