CAJ | 학술논문

青海省囊谦县钾质碱性岩岩石化学成分富碱（Na2O+K2O=7.20%~10.6%），高钾（Na2O/K2O=0.56~0.93）和富钙（CaO=1.65%~6.39%），富集Rb，Ba，Th，U，Sr等大离子亲石元素（ LILE）和Pb，亏损Nb，Ta，Zr，Hf，Ti等高场强元素（ HFSE）。∑REE范围为336.8×10-6~611.31×10-6，富集轻稀土（LREE/HREE=19.78~33.58）和铕异常不明显（δEu=0.96~1.05）。粗面玄武岩、二长斑岩、正长斑岩LA-ICP-MS U-Pb定年结果分别为34.9±1.2 Ma，35.0±1.1 Ma，35.3±0.5 Ma，均属于古近纪，相当于晚始新世。从本文定年结果还表明斑岩（花岗斑岩）成岩时间略早于火山岩，暗示该区的岩浆作用，有先侵入后喷发的趋势。囊谦钾质碱性岩的成因与印度、欧亚两大陆碰撞有内在的联系。
청해성낭겸현갑질감성암암석화학성분부감（Na2O+K2O=7.20%~10.6%），고갑（Na2O/K2O=0.56~0.93）화부개（CaO=1.65%~6.39%），부집Rb，Ba，Th，U，Sr등대리자친석원소（ LILE）화Pb，우손Nb，Ta，Zr，Hf，Ti등고장강원소（ HFSE）。∑REE범위위336.8×10-6~611.31×10-6，부집경희토（LREE/HREE=19.78~33.58）화유이상불명현（δEu=0.96~1.05）。조면현무암、이장반암、정장반암LA-ICP-MS U-Pb정년결과분별위34.9±1.2 Ma，35.0±1.1 Ma，35.3±0.5 Ma，균속우고근기，상당우만시신세。종본문정년결과환표명반암（화강반암）성암시간략조우화산암，암시해구적암장작용，유선침입후분발적추세。낭겸갑질감성암적성인여인도、구아량대륙팽당유내재적련계。
The potassic alkalic rocks at Nangqian County, Qinghai Province are characterized by alkali-rich (Na2O+K2O=7.20%-10.6%), high potassium (Na2O/K2O=0.56-0.93) and high calcium(CaO=1.65%-6.39%). The large-ion lithophile elements (LILE, Rb, Ba, Th, U and Sr) and Pb of the potassic alkalic rocks are more enriched while the high field strength elements (HFSE, Nb, Ta, Zr, Hf and Ti) are deficient. The concentration of rare earth elements (REE) the potassic alkalic rocks is distributed in a range from 336.8×10-6 to 611.31×10-6 with enriched light REE (LREE/HREE=19.78-33.58) and the Eu anomaly of the rocks is not obviously (δEu=0.96-1.05). LA-ICP-MS zircon U-Pb age of the basalt, ivernite and syenite porphyry were obtained as the values of 34.9±1.2 Ma, 35.0±1.1 Ma and 35.3±0.5 Ma respectively, which shows a trend that the magma eruption process was followed the magma intrusion. And it comes to the conclusion that there exits some inherent relationship within the collision between the India slab and Europe-Asia slab.