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粤西连阳复式岩体由燕山早期连阳花岗岩岩体(锆石 U-Pb 年龄为144.3±0.8Ma)和燕山晚期白浆花岗岩岩体(锆石 U-Pb 年龄为106.4±0.7Ma)组成。这两个岩体在岩石化学上均富硅,属准铝质,并相对富钾。在微量元素组成上,连阳岩体和白浆岩体都强烈亏损 Ba、Sr 和 Ti,轻微亏损 Nb 和 Ta。两岩体的稀土元素特征类似,总量比较高,分别为187.6～300.6×10~(-6)和185.5～294.3×10~(-6),轻稀土富集,LREE/HREE 分别为4.17～9.28和4.13～7.08,(La/Yb)_N 分别为3.66～9.03和3.29～5.16,Eu 明显亏损,δEu 值分别为0.04～0.53和0.04～0.16。连阳岩体的ε_(Nd)(t)为-9.1～-7.6,白浆岩体的ε_(Nd)(t)为-9.8～-7.8,两者具有相似的 Nd 同位素组成。钕模式年龄分别为1.56～1.68Ga 和1.54～1.71Ga。研究表明,连阳复式岩体燕山期花岗岩形成于地壳剪切-拉张的构造背景下,是中元古地壳部分熔融的产物。
The western part of Yangyang western dolomite is composed of the Lianshan granite (U-Pb zircon age 144.3 ± 0.8Ma) and late Yanshan white granite granite (zircon U-Pb age 106.4 ± 0.7Ma) . Both rocks are silicon rich in petrochemistry, are quasi-aluminum, and are relatively potassium-rich. In the trace element composition, both Yang and Bai limestone bodies strongly depleted Ba, Sr and Ti, slightly depleted Nb and Ta. The REEs of the two rock mass are similar and their total contents are relatively high, ranging from 187.6 to 300.6 × 10 ~ (-6) and 185.5 ~ 294.3 × 10 ~ (-6), respectively. The light rare earths are enriched with LREE / HREE of 4.17 ~ 9.28 and 4.13 ~ 7.08, (La / Yb) _N were 3.66 ~ 9.03 and 3.29 ~ 5.16, respectively. The Eu values were obviously depleted and the δEu values were 0.04-0.53 and 0.04-0.16, respectively. Ε_ (Nd) (t) is -9.1 ~ -7.6 in Lianyang pluton and ε_ (Nd) (t) is -9.8 ~ -7.8 in calcareous pluton, which have similar Nd isotope compositions. Neodymium model age were 1.56 ~ 1.68Ga and 1.54 ~ 1.71Ga. The research shows that the Yanyanshan granite in the Lianyang complex rock body formed under the shear-tension structural background of the crust and is a product of partial melting of the Paleoproterozoic crust.