CAJ | 학술논문

　　龙泉山作为四川前陆盆地的前陆隆起带，记录了龙门山造山带地质构造演化的重要信息。本文对川西平原东侧龙泉山白垩系泥质岩样品的进行了常量元素、微量元素和稀土元素测试，根据泥质岩的地球化学特征讨论了物源区的性质、构造背景及风化等特征，为探讨龙门山与四川盆地的盆山耦合过程提供了地球化学方面的资料。研究区泥质岩的K2O/Al2O3， Al2O3/TiO2，Cr/Zr和Th/Sc的比值均表明其物源区以长英质岩石为主；REE配分模式中，（La/Yb）N的均值为8.99，δEu的均值为0.70，表现出轻、重稀土分馏程度较高并呈中等负Eu异常的特征；La-Th-Sc和Th-Sc-Zr/10三角图表明物源区经历了大陆岛弧、活动大陆边缘和被动大陆边缘的地质构造演化过程；指示化学风化程度的CIA指数及成分成熟度的ICV指数的平均值分别为71和1.43，表明物源区经历了中等的风化作用，揭示了白垩纪时期物源区及四川盆地均属炎热的半干旱-干旱气候环境。
　　룡천산작위사천전륙분지적전륙륭기대，기록료룡문산조산대지질구조연화적중요신식。본문대천서평원동측룡천산백성계니질암양품적진행료상량원소、미량원소화희토원소측시，근거니질암적지구화학특정토론료물원구적성질、구조배경급풍화등특정，위탐토룡문산여사천분지적분산우합과정제공료지구화학방면적자료。연구구니질암적K2O/Al2O3， Al2O3/TiO2，Cr/Zr화Th/Sc적비치균표명기물원구이장영질암석위주；REE배분모식중，（La/Yb）N적균치위8.99，δEu적균치위0.70，표현출경、중희토분류정도교고병정중등부Eu이상적특정；La-Th-Sc화Th-Sc-Zr/10삼각도표명물원구경력료대륙도호、활동대륙변연화피동대륙변연적지질구조연화과정；지시화학풍화정도적CIA지수급성분성숙도적ICV지수적평균치분별위71화1.43，표명물원구경력료중등적풍화작용，게시료백성기시기물원구급사천분지균속염열적반간한-간한기후배경。
As the foreland forebulge,Longquan Mountain records important information about tectonic evolution of the Longmenshan tectonic belt. This paper studies major, trace, and rare earth elements (REE) of the Cretaceous argillaceous rocks in the Longquan Mountain of western Sichuan. Based on these data, we discuss the provenance, tectonic setting, and weathering of source rocks. Ratios of K2O/Al2O3、Al2O3/TiO2,Cr/Zr and Th/Sc show that the detritus were derived mostly from felsic rocks in the source areas. In the REE mantle-normalized pattern, the (La/Yb)n value is 8.99 on average, and δEu value is 0.70 on average, which shows enrichment in light REEs and a moderate negative Eu anomaly. The triangular plots of Th-Co-Zr/10 and Th-Sc-Zr/10 show that the tectonic setting was probably continental island arc, active continental margin and passive continental margin. The average of chemical index of alteration (CIA=71) and index of chemical variation (ICV=1.43)indicate that the provenance area underwent moderate weathering and reveal a hot semiarid to arid climatic environment.