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南太行山平顺闪长岩锆石SHRIMP测年表明闪长岩体形成于(125.5±2.3)Ma,与太行山其他地区乃至整个华北地区侵入杂岩体具有相近的形成年代,表明在晚中生代(115～135Ma)太行山地区与华北地区经历了相同的构造岩浆事件。平顺闪长岩w(SiO2)=48.57%～63.54%,w(Al2O3)=13.53%～19.15%,w(MgO)=1.20%～9.31%,w(TiO2)=0.34%～1.07%,w(CaO)=3.13%～10.39%,w(K2O+Na2O)=4.78%～7.99%,Mg#=0.37～0.72,LREE富集HREE亏损,略显微弱的正Eu异常,以富集LILE、LREE元素和亏损Nb-Ta等高场强元素为特征。闪长岩(206Pb/204Pb)i=17.775～18.857,(207Pb/204Pb)i=15.522～15.602,(208Pb/204Pb)i=38.044～38.502,εNd(125Ma)=-17.009 56～-9.606 32,ISr=0.705 85～0.707 53,表明起源于EMI富集地幔,并受到地壳物质和EMII型富集地幔混染,可能说明在晚白垩世太行山地区与整个华北克拉通都发生了岩石圈减薄事件。
The zircon SHRIMP dating of the Nanchang Taihshang ductile diorite shows that the diorite body formed at (125.5 ± 2.3) Ma and has a similar age of formation with the intruded complex in other parts of the Taihang Mountains and the whole of North China, indicating that during the late Mesozoic (115 ~ 135Ma) The Taihang Mountains and North China experienced the same tectonomagmatic events. The wurtzite diorite has the following properties: w (SiO2) = 48.57% ~ 63.54%, w (Al2O3) = 13.53% ~ 19.15%, w (MgO) = 1.20% ~ 9.31%, w (TiO2) = 0.34% ~ 1.07% (K2O + Na2O) = 4.78% ~ 7.99%, Mg # = 0.37 ~ 0.72. The LREE is rich in HREE depletion and slightly faint positive Eu anomaly, so as to enrich LILE and LREE elements And loss of Nb-Ta contour elements such as high field strength is characterized. (206Pb / 204Pb) i = 17.775-18.857, (207Pb / 204Pb) i = 15.522-15.602, (208Pb / 204Pb) i = 38.044- 38.502, εNd (125Ma) = - 17.009 56-9.606 32, ISr = 0.70585 ~ 0.707 53, indicating that it originates from EMI-enriched mantle and is contaminated by crustal materials and enriched EMII-type mantle, which may indicate that lithospheric thinning occurred in both the Late Cretaceous and the entire North China craton.