论文部分内容阅读
岚山头一带含霓石碱长花岗岩分布在胶南造山带的南段，是华北板块与扬子板块碰撞晚期在引张环境下形成的A型花岗岩。该花岗岩含有霓石、钠闪石、微斜长石、钠长石等碱性矿物；K2O和Na2O的含量为8．4％～9．6％，H2O＋少于0．16％，具有富碱、贫水的特点；稀土元素总量在262．19×10－6～313．23×10－6范围内，87Sr／86Sr初始比值为0．72902；Pb－Pb同位素年龄值为622．7Ma。含霓石碱长花岗岩体内含有较多的柯石英榴辉岩、榴辉岩包体。柯石英榴辉岩为超高压变质作用的产物，而其围岩（含霓石碱长花岗岩）却保存下了岩浆成因的霓石，处于富Na、Al、Si变质环境中，未出现硬玉或硬玉分子较高的绿辉石。这说明含霓石碱长花岗岩没有经受过超高压变质作用，即柯石英榴辉岩相对其围岩而言是外来的。
The Lanshan head area contains imigantite-bearing long granites distributed in the southern segment of the Jiaonan orogen and is the A-type granite formed in the lead-up environment at the late collision between the North China Plate and the Yangtze Plate. The granite contains alkaline minerals such as aegirine, salsamite, micro plagioclase, albite and the like; the content of K2O and Na2O is 8.4% -9.6%, the content of H2O + is less than 0.16% , The characteristics of poor water; the total amount of rare earth elements in the range of 262.19 × 10-6 ~ 313.23 × 10-6, 87Sr / 86Sr initial ratio of 0.72902; Pb-Pb isotope age value of 622.7Ma. Nime-soda-containing long granite body contains more coesite eclogites, eclogite inclusions. Keshiying eclogite is the product of ultrahigh-pressure metamorphism, while the surrounding rocks (including the Ni-S-Alkaline granite) have preserved the magma-forming Aegilite in the environment rich in Na, Al and Si-rich, with no jadeite or Jadeite higher mossite. This shows that the ammoniated alkali-bearing granite has not undergone UHP metamorphism, that is, the keroite eclogite is exotic to its surrounding rock.