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燕山期花岗质岩石广泛出露在冀北地区，从中可以识别出碱钙性、过铝质和碱质三个岩石系列。本文系统报道了它们的产状、岩类学、主要元素、痕量元素、稀土元素、年代学和ＩＳｒ资料；重点讨论了它们的地球化学特征和成因类型问题。碱钙性岩石系列主要由石英二长闪长岩元素、二长花岗岩元素、正长花岗岩构成；ＳｉＯ２含量变化范围是６２％～７５％；Ｋ２Ｏ＋Ｎａ２Ｏ在７．６３％～８．８８％之间；Ａ／ＣＮＫ＜１．０５，ＣＡ指数５５。过铝质系列由流纹斑岩为代表，具有高硅（ＳｉＯ２＞７３％）、富钾低钠（Ｋ２Ｏ／Ｎａ２Ｏ为１．４４～９．１３）、过铝质（Ａ／ＣＮＫ是１．１７～１．４３）的特点。碱性系列的岩石组合是碱长正长岩（碱长粗面岩）－碱性石英正长岩（碱流岩）－碱性花岗岩（碱性流纹质熔结凝灰岩）。它们的ＳｉＯ２含量变化于５７％～７７％之间，Ｋ２Ｏ＋Ｎａ２Ｏ、Ｋ２Ｏ、Ｎａ２Ｏ分别大于９％、４％、５％，ＮＫ／Ａ为０．９～１．１２。以过铝质、碱钙性和碱性为序，三个岩石系列的Ｎｂ、Ｔａ、Ｚｒ、Ｈｆ、ＲＥＥ含量依序增高，显示出明显的区别。上述特征表明，三个岩石系列的性质和特征明显不同，分别属于三种岩石成因类型。
Yanshanian granitic rocks are widely exposed in the northern Hebei area, from which you can identify the alkaline calcium, aluminum and alkaline three series of rocks. This paper systematically reports their occurrence, petrography, major elements, trace elements, rare earth elements, chronology and ISr data; focuses on their geochemical characteristics and types of genetic problems. The series of alkali-calcium rocks mainly consist of quartz monzodiorite, monzogranite and orthoclase granite; the content of SiO2 varies from 62% to 75%; K2O + Na2O ranges from 7.63% to 8.88% A / CNK <1.05, CA index 55. The peraluminous series is represented by rhyolite porphyry and is characterized by high silicon (SiO2> 73%), potassium-rich and low sodium (K2O / Na2O = 1.44-9.13) and aluminum perchlorate (A / CNK = 1). 17 ~ 1.43) features. Alkaline series of rock assemblages are alkali-bearing syenite (alkali-bearing mafic) -basic quartz syenite (alkali-flowing rock) -basic granite (alkaline rhyolitic melted tuff). The content of SiO2 varies from 57% to 77%. The K2O + Na2O, K2O and Na2O are more than 9%, 4% and 5%, respectively, and the NK / A is from 0.9 to 1.12. The sequence of Nb, Ta, Zr, Hf and REE in the three series of rocks increased in order of peraluminous, alkaline calcium and alkaline, showing obvious differences. The above characteristics show that the nature and characteristics of the three series of rocks are obviously different and belong to three types of rock genetic types respectively.