| Different occurrence state of the element in geological samples is animportant criterion of studying geochemistry property. Ascertainment ofoccurrence state is an important significance of finding effective prospectinginformation and studying property of geochemical behavior. Phase and stateanalysis comprise chemical phase analysis and state analysis of the element.The latter is also called occurrence state analysis of the element,when weare studying geological samples. The occurrence forms in a certain concretemineral of element are more complicated,which may be single substance,intermetallic compound,compounds,allomerism,ionic adsorption,etc. Soit is more reasonable,more precise,more faster to definite the industry valueof mineral deposit in using phase and state analysis than chemical phaseanalysis in complicated geological supplies. Pt and Pd are the most effectiveand direct pathfinder elements to search for PGE deposit. One of the mosteffective method of searching platinum deposit is to reconnoiter geochemis-tries of the PGE,and to find out the distribute of the PGE,and the law of thePGE.The platinum group metals have a lot of unique,excellent physical andchemical properties. There are many very extensive and importantapplications in national economy and new high-tech industy,which isknown as "the modern industry vitamin"as far back as the sixties of the20th century. In the past twenty and thirty years,with the forming anddevelopment of the new and high technology and industry.The applicationof the PGE is expanding constantly,and it is unable to be replaced by othermaterials so far. So the platinum group metals are promoted as"primaryigh-tech metal"in the eighties of the 20th century. Such importantstrategic position will get reflecting constantly in the sustainabledevelopment of the human society in 21st century.The gold and silver resources of China are more abundant,but morethan 98% of the metal resources of platinum group metals centralize in sucha few areas as South Africa,Russia,North America,etc.,forming theabsolute monopoly situation. The resource only account for 0.6% of theworld in the platinum group metal ores which our country has alreadyverified,and the grade is low.The fluid inclusion is a sample of the natural mineralizing solution. Itcan be as a decipher of mineralization,especially the password of endogenicmetallization. Fluid inclusions directly write down physical and chemicalcomposition,and it is a direct sample to study the forming,moving,changing and the following geochemistry course. The fluid inclusionsrecord the terms and history of forming the mineral fully,and it is one of themost important characteristics of mineral. Inclusion mineralogy is one of themost important basic theories to reconnoiter new mineral deposit and searchlatent mineral deposit.The famous Qianxi basalt is one of the five biggest overflow basalts inTertiary Period Five. The investigators have done many important work forenrichment and determination of the PGE , having many valuableinformation,but the determination of Pt,Pd in the fluid inclusions of thebasalt is not studied.Abundant degree of the PGE in the earth's crust is extremely low,andits Clark value Pt is 5×10-9,Pd is 10×10-9 . The PGE load among thesilicon and oxygen system of mafic minerals,the industrial type of themineral deposit is the copper-nickel sulphide of the mantle source platinummineral deposit. It is determined that the PGE has a high backgroundunusually in the basic rock of Qianxi basalt. There are many importanttheories and effective significance for recurring the movement andenrichment of the element in ancient fluid to study the fluid inclusions of thePGE in the area. Determination the content and the forms of the PGE in thisfluid inclusion,giving the effective criterion for information of mineralizingof the PGE.In this page,the basalt is leached by the acid,regulating the acidity ofHCl into 1.50mol/L,exchanging and concentrating Pt,Pd by C-410 resin.After the resin is desiccated and incinerated,the bottom is dissolved withaqua regia,controlling the acidity of HCl to 2~5% and the constant volumeis10mL,which is determined by ICP-MS. The detection limits for Pt and Pdof the method is 0.40ng/mL and 0.19ng/mL respectively. The results are inagreement with certified values with precision of 28.7% RSD for Pt and15.6% RSD for Pd. Relative error of this method is less than 25.0%.The basalt sample is dissolved with the solution of NH4Cl ,electromagnetic mixed for 4h and sucked with microporous filtering film.The bottom is taken into the ceramic crucible and desiccated,then thebottom is burst at 800℃and leached according to the above approach. Thefiltrate is concentrated to 50mL at 80℃,regulating the acidity of HCl into1.50mol/L,exchanging and concentrating Pt,Pd by C-410 resin. After theresin is desiccated and incinerated,the bottom is dissolved with aqua regiaand the constant volume is10mL,which is determined by ICP-MS. Thecomposition of the fluid inclusions in basalt shows that the content of thefluid inclusions is equal to the content of Pt,Pd in the carrier of basalt. Theacquirement of content of the fluid inclusions provides the evidence aboutthe existence,movement and distribution of the PGE.In the base of the lithology appraisal,a new procedure employed thephase and occurrence state analysis of Pt and Pd was described in the paper.In the same meaning,a procedure of Pt and Pd in the occurrence states ofadsorbed state,silicate,mutual compound and isomorphism state wasdetermined. The result shows that the major formality in the occurrencestates of Pt and Pd in Qianxi basalt exist as silicate and mutual compound,and few formality as adsorbed and isomorphism state. The result ofverifying the phase and occurrence state of Pt and Pd offered scientific basicfor studying the geochemical prospecting.At the same time,the basalt sample was given to Xi'an institute ofgeology and mineral resources and Institute of geology and geophysics...
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