CAJ | 학술논문

对小秦岭文峪和娘娘山花岗岩体进行的锆石SHRIMP U-Pb定年和岩石地球化学分析结果表明,文峪和娘娘山黑云母二长花岗岩体属于Ⅰ型花岗岩,是太古宙太华群高级变质岩系经部分熔融的产物.它们的成岩年龄分别为138.4±2.5 Ma和141.7±2.5 Ma,略早于本区拆离伸展活动的时限,暗示了中下地壳部分熔融形成的岩浆热穹窿和花岗质岩浆在上地壳的大面积侵位导致了小秦岭变质核杂岩的发育.花岗岩体的成岩年龄都早于本区金矿床的主期成矿时代,从时间上表明了花岗质岩浆活动与金矿成矿作用无直接关系.
대소진령문욕화낭낭산화강암체진행적고석SHRIMP U-Pb정년화암석지구화학분석결과표명,문욕화낭낭산흑운모이장화강암체속우Ⅰ형화강암,시태고주태화군고급변질암계경부분용융적산물.타문적성암년령분별위138.4±2.5 Ma화141.7±2.5 Ma,략조우본구탁리신전활동적시한,암시료중하지각부분용융형성적암장열궁륭화화강질암장재상지각적대면적침위도치료소진령변질핵잡암적발육.화강암체적성암년령도조우본구금광상적주기성광시대,종시간상표명료화강질암장활동여금광성광작용무직접관계.
The zircon SHRIMP U-Pb dating and petrochemistry study on the Wenyu and Niangniangshan granitic plutons in the Xiaoqinling area,central China,have been carried out in this paper.The results indicate that the Wenyu and Niangniangshan biotite monzogranites belong to the I-type granite,which are the products of partial melting of high-grade metamorphic rocks of the Archean Taihua Group.and their ages are of 138.4±2.5 Ma and 141.7±2.5 Ma respectively.The age data are slightly older than the time of detachment extension in this area,implying that the Xiaoqinling metamorphic core complex is resulted from the formation of magma thermal dome within middle-lower crust,and the upwelling and emplacement of granitic magma within upper crust.The age data are also older than the gold ore-forming time,showing there is no direct relationship between the granitic magmatism and large-scale gold mineralization in the Xiaoqinling area.