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在元素地球化学分类中,钛属铁族元素,在内生作用过程中;二者(Fe、Ti)有对应聚、散的趋势,在超基性—基性岩浆结晶分异早期,随着富镁硅酸盐矿物(镁橄榄石、贵橄榄石等)的结晶分离作用,岩浆中铁的含量增高,即F值((Fe_2O_3+FeO)/(Fe_2O_3+FeO+MgO)(重量％))增大,钛含量亦逐渐增加。而在表生条件下,钛是比较稳定的元素,通常不形成可溶性化合物,故很难在水中溶解迁移;而铁则比钛活泼得多,在内生作用条件下形成的各种含铁矿物,在表生条件下极易氧化、分解,生成氧化物以肢体、悬浮或真溶液的形式在水中迁移,故在地表风化～剥蚀～搬运～沉积过程中,钛、铁的分离程度越来越大,二者的集散呈现明显的负相关趋势。所以,由岩浆岩或沉积岩变质形成的正、副角闪岩,其F—TiO_2的相关变异有截然不同的趋势,可用以鉴别不同的角闪岩的原岩类型。
In the elemental geochemistry classification, Ti is an iron family element and undergoes endogenous processes; both (Fe, Ti) have a tendency of corresponding polydispersion, and in the early stage of ultrabasic-basic magma crystallization differentiation, Crystallization of magnesium-rich silicate minerals (magnesium olivine, virgin olivine, etc.), increased iron content in magma, that is, F value ((Fe_2O_3+FeO)/(Fe_2O_3+FeO+MgO) (wt%)) increased Large, titanium content has also gradually increased. Under supergene conditions, titanium is a relatively stable element, and usually does not form soluble compounds, so it is difficult to dissolve and migrate in water; while iron is much more active than titanium, and various iron-containing ore formed under intrinsic action conditions. The substance is easily oxidized and decomposed under supergene conditions, and the oxides are migrated in water in the form of limbs, suspensions or true solutions. Therefore, the degree of separation of titanium and iron in the process of surface weathering, erosion, handling, and deposition is increasing. The larger, the distribution of the two shows a significant negative correlation trend. Therefore, the variability of F-TiO_2 formed by metamorphism of magmatic rocks or sedimentary rocks has distinctly different trends and can be used to identify different types of primary amphibolite rock types.