论文部分内容阅读
There has been found a distinct directinnal trend of kimberlites differing in ore-bearingpotentiality with changing chemical composition.The contents of MgO,NiO and Cr_2O_3 dec-rease gradualy while Na_2O,K_2O,Al_2O_3 and P_2O_5 increase considerably in the or-der of diamond-rich——diamond-poor——diamond-barren kimberlites.In general Fe_2O_3,FeO andTiO_2 also show an increasing tendency.Therefore,the variations in chemical compositionmay be used as petrochemical indexes for calculating the ore-bearing potentiality of kimber-lites.Based on discriminant analysis,it is possible to make a distinction between diamond-bearing and diamond-barren,or between diamond-rich and diamond-poor kimberlites.
There has been found a distinct directinnal trend of kimberlites differing in ore-bearing potentiality with changing chemical composition. The contents of MgO, NiO and Cr 2 O 3 decorease gradualy while Na 2 O, K 2 O, Al 2 O 3 and P 2 O 5 increase considerably in the or- der of diamond- rich - diamond-poor - diamond-barren kimberlites. general Fe 2 O 3, FeO and TiO 2 also show an increasing tendency. Therefore, the variations in chemical composition may be used as petrochemical indexes for calculating the ore-bearing potentiality of kimber-lites. on discriminant analysis, it is possible to make a distinction between diamond-bearing and diamond-barren, or between diamond-rich and diamond-poor kimberlites.