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波罗诺和大光顶岩体主要为闪长岩、石英闪长岩、英云闪长岩、花岗闪长岩和少量含斜长石的角闪石岩、角闪辉长岩组成.波罗诺石英闪长岩的锆石SHRIMPU-Pb年龄为(296±4)Ma,代表岩体的侵位年龄.含斜长石的角闪石岩具有明显的堆晶结构,并具有上凸形的稀土分布模式和含量变化很大的相容元素(如:Co,V,Sc),表明它可能是堆晶成因.波罗诺和大光顶中酸性岩体中常见闪长质微粒包体(MME),斜长石具有明显的结构和成分不平衡现象,表现为核部富钙(An=46～50)和幔部富钠(An=26～33)的特征,而且变化截然.全岩具有富集且变化量较大的εNd(t)值(–16.5～–11.8)和εHf(t)值(–22.5～–16.8),并且εNd(t)值与SiO2负相关.这些特征都说明了中酸性岩的形成可能与来自富集地幔部分熔融并经历充分演化的基性岩浆与壳源花岗质岩浆相互混合形成混浆、再经历一定程度的分离结晶作用的复杂过程有关.混浆经历以角闪石为主(及少量的辉石+磷灰石+锆石)的分离结晶过程是造成中酸性岩浆具有高Sr,Sr/Y和低Yb的埃达克岩的特征的重要原因之一.波罗诺和大光顶岩体具有富集大离子亲石元素(Ba,Sr),亏损高场强元素(Nb,Zr,Ti)的弧岩浆的特征,它们的形成可能与古生代期间古亚洲洋板片不断向华北克拉通之下俯冲有关.
The Boluo and Da Guangding bodies are dominated by diorite, quartz diorite, diorite, granodiorite and a small amount of amphibole-bearing rocks containing amphibolite and hornblende gabbro. The zircon SHRIMPU-Pb age of (296 ± 4) Ma for the Pororo quartz diorite represents the age of emplacement of the pluton.The amphibole-bearing rocks containing plagioclase have a pronounced heap- Shaped REE patterns and compatible elements (eg, Co, V, Sc) with widely varying contents indicate that it is probably a causative genesis of the heapsites.The common diorite particles (MME) and plagioclase have obvious structural and compositional imbalances, which are characterized by rich calcium in the core (An = 46-50) and sodium rich in the mantle (An = 26-33). The values of εNd (t) (-16.5 ~ -11.8) and εHf (t) (-22.5 ~ -16.8), which are enriched and vary greatly, are negatively correlated with SiO2 Both suggest that the formation of moderately acidic rocks may be complicated by the intermixing of mafic and crustal derived granitic magma from the partially melted and well-evolved mantle enriched mantle and then undergoing some degree of segregation and crystallization The separation and crystallization process in which the hornblende was dominated by hornblende (with a small amount of pyroxene + apatite + zircon) was the adakite that resulted in high Sr, Sr / Y and low Yb .Poronuo and Daguangding bodies have the characteristics of arc magma enriched in large ion lithophile elements (Ba, Sr) and depleted high field elements (Nb, Zr, Ti) May be related to the continuous subduction of the Paleo-Asian ocean plate during the Paleozoic to the North China Craton.