DISCRIMINANT ANALYSIS OF GENETIC TYPE OF CARBONATE ROCK AND DISCUSSION ON GENETIC DOLOMITITE IN BAI YINOBO REGION
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摘要: 本文根据对世界上20多个国家和我国21个省碳酸盐岩石化学全分析数据的统计和换算结果,发现岩浆碳酸岩与沉积碳酸盐岩之间常量元素的一般含量无显著不同,但采用两组或逐步判别分析的方法,仍能将岩浆碳酸岩与沉积碳酸盐岩很好的区分开。判别效率可达90%以上。将这一方法应用到白云”鄂博矿区的“白云岩”和灰岩,90%以上的“白云岩”样品判为岩浆碳酸岩,灰岩的样品全部判为沉积碳酸盐岩,与它们的地质产状和地球化学特征一致。Abstract: The writer collected 769 data on bulk analysis of carbonate rock and carbonatite from more than 20 country in the world and 21 provinces of china.Results of statistics and calculation indicated that content ranges of main elements between sedimentary carbonate rock and carbonatite are similar.The carbonatite can be distinguished from sedimentary carbonate rock by discriminant anaalysis.The carbonatite is P2O5-rich and usually content of P2O5 is more than0.2% .The number of data, P2O5 0.2% , is 86% of all carbonatite data. But sedimentary carbonate rock is P2O5-poor.The number of data, P2O50.2% only makes up 12% in all this rock s data.Therefor, content of P2O5 is one important standard for discriminanting genetic type of carbonate rock. When eleven variables are adopted in two set discriminant analysis, discriminanting efficiency of various genetic type of calcareous carbonate rocks, dolomitic carbonate rocks and ferruginous carbonate rock is 93.5%, 90.7% and 89.8% separetaly. When P2O5, Na2O, A12O3, MnO, CaO, K2O and Fe2O3 are used as discriminating variables in discriminant analysis of step by step, discriminanting effect of calcareous carbonate rock is the best and discriminanting efficiency is 94. 5%. While FeO, Fe2O3, Al2O3 and P2O5 are adopted in discriminant analysis for dolomitic carbonate fock, process of calculation is more simple and discriminanting efficiency reached 96% . Using CaO. P2O5 MgO, SiO2, Fe2O3 and Al2O3 for discriminant analysis of ferruginous carbonate rocks, discriminanting efficiency comes up 98. 5% . Generally, discriminanting effect of sedimentary carbonate rocks (near 100%) is better than carbonatite (more than 85% ) , i.e. sedimentary carbonate rock generally isn ' t distinguished.Results of discriminant analysis of limestone and dolomitite from Baiyinobo region indicat that 17 samples of limestone are all distinguished sedimentary carbonate rock, but 3 samples in 57 samples of dolomitite are distinguished sedimentary carbonate rock, making up 5.3% of collecting data, other samples are distinguished carbonatite.The conclusion is in accord with its geological occurrence, geochemical and isotopic composition characteristics
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[1] (1)凃光炽等,1983,中国层控矿床地球化学,第一卷,70-247页,科学出版社。
(2)菱铁矿矿床学术会议论文集,1983, 72-213页,科学出版社:
(3)金兹堡A·N., 1965稀有元素矿产地质,第一辑,稀有金属碳酸岩,地质出版社;
(4)孟庆润,1982,论白云鄂博铁矿含矿围岩一白云岩的沉积成因及其深积环境分析,地质论评,第五期,481488页
(5)姜传武等,1982,论白云鄂博矿床同位素地质研究,中国科学院地质研究怕地质研究成果选编。 第一集,文出版社;
(6)李士勤,1983,再论内蒙古白云鄂博含稀有金属碳酸岩及其妮、稀土、铁矿床成因,中国北方板 块构造文集,第一集,155-184页;
(7)刘铁庚,1985,白云鄂博白云碳酸岩地质和地球化学特征,第3期,16-18页
(8)白鸽袁忠信,1985,中国地质科学院矿床地质研究所所刊,碳酸岩地质及其矿产专辑,地质出版 社
(9)周振玲等,1980,内蒙古白云鄂博白云碳酸岩的地质特征及其成因探讨,地质论评,135页;
(10)刘铁庚1986,再论白云鄂博白云岩的成因,地质与勘探,第8期,35-40页;
(11)刘铁庚,1986,白云鄂博白云岩的氧、碳同位素特征及其成因讨论,地质论评,第2期,150-159;
(12)Chillinger G.V., 1967, Carbonate rocks (9B),Lodon Nwe York Sydney;
(13) "Tuttle O.F.and Gittins J.1966, Carbonatite. p.42-240, London New York Sydney;
(14)Cauouiof B.C., 1977, Kapsohamunfl, C.28-179, Uzgameilmfo 《Hayka》;
(15)Tehofou B.U.,1977, Kapsohamunfle uux noiezhfle uckonaeufle, c.29-142, Uzgameilcmfo lehuhpagckozo yhufercumema.
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