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帽峰花岗岩体是粤北贵东复式花岗岩体中一个重要的产铀岩体。单颗粒锆石U-Pb定年结果为219．6±0．9Ma, 属于印支期岩浆活动产物。该岩体的主要元素显示富硅、富碱、强过铝质和低CaO／Na2O比值等特征。微量元素富集Rb,Th, U,Ce,Sm和Y而亏损Ba,Sr,P和Ti;LREE轻微富集(LREE／HREE=1．70-9．63,(La／Yb)N=0．41-6．25),Eu亏损明显(δEu=0．02-0．22);具有低的εNd(t)值(-12．3--10．8),变化的δ18O(4．1-11．3‰)、(87Sr／86Sr)i(0．71049- 0．73359)、206Pb／204Pb(18．345-22．019)和207Pb／204Pb(15．646-15．863)以及古老的Nd模式年龄(1879-1996Ma)。以上特征表明,帽峰岩体属于典型的壳源型花岗岩,是在地壳伸展-减薄的构造背景下,通过古元古代成分不均一的泥质变质岩低程度部分熔融的方式形成。
Maofeng granite body is an important production uranium rock body in Guidong multi-granite body in northern Guangdong. The result of U-Pb dating of single grain zircon is 219.6 ± 0.9Ma, belonging to the Indosinian magmatism. The major elements of this rock mass are characterized by rich silicon, alkali-rich, strong-peraluminous and low CaO / Na2O ratios. Trace elements enriched in Rb, Th, U, Ce, Sm and Y and lost Ba, Sr, P and Ti; LREE slightly enriched (LREE / HREE = 1.70-9.63, (La / Yb) N = 0 .41-6.25), the depletion of Eu was significant (δEu = 0.02-0.22), with a low value of εNd (t) (-12.3-10.8), the variation of δ18O (4.1 -11.3 ‰), (87Sr / 86Sr) i (0.71049-0.73359), 206Pb / 204Pb (18.345-22.019) and 207Pb / 204Pb Nd mode age (1879-1996Ma). The above characteristics indicate that the caprock body belongs to the typical crust-sourced granite and is formed by the low-degree partial melting of the muddy metamorphic rocks with uneven Paleoproterozoic composition under the tectonic extension and thinning of the crust.