CAJ | 학술논문

本文对新疆中天山南缘乌瓦门蛇绿混杂岩中的超镁铁岩进行了岩石矿物学和地球化学研究，对其成因和形成环境进行限定。乌瓦门蛇绿混杂岩中的超镁铁岩为蛇纹石化二辉橄榄岩，由橄榄石（Fo=89.1~90.6）、斜方辉石（Wo0.4-2.4En87.2~90.7Fs8.9-10.9；Mg#=89.0~91.0）、单斜辉石（Wo49.1-51.3En16.0~48.4Fs0.9-4.3；Mg#=90.2~92.1）和尖晶石（Mg#=71.8~77.5；Cr#=9.3~13.4）组成。主量元素组成上，以低MgO（37.74%~41.34%）、高Al2O3（2.58%~3.39%）、高CaO（2.23%~3.68%）和高TiO2（0.05%~0.11%）为特征。微量元素上，亏损稀土元素（REE总量为1.73×10?6~4.63×10?6），亏损不相容元素（如，Rb=0.4×10?6~1.39×10?6，Zr=0.73×10?6~3.28×10?6，Hf=0.04×10?6~0.11×10?6），富集相容元素（如，Cr=2516×10?6~2793×10?6，Co=84.6×10?6~119×10?6，Ni=1641×10?6~2261×10?6）。矿物学和地球化学特征一致指示，乌瓦门蛇绿混杂岩中的超镁铁岩为经历过低程度（5%~10%）部分熔融作用的残余地幔橄榄岩，形成于洋中脊环境，是MOR型蛇绿岩中的地幔橄榄岩。
본문대신강중천산남연오와문사록혼잡암중적초미철암진행료암석광물학화지구화학연구，대기성인화형성배경진행한정。오와문사록혼잡암중적초미철암위사문석화이휘감람암，유감람석（Fo=89.1~90.6）、사방휘석（Wo0.4-2.4En87.2~90.7Fs8.9-10.9；Mg#=89.0~91.0）、단사휘석（Wo49.1-51.3En16.0~48.4Fs0.9-4.3；Mg#=90.2~92.1）화첨정석（Mg#=71.8~77.5；Cr#=9.3~13.4）조성。주량원소조성상，이저MgO（37.74%~41.34%）、고Al2O3（2.58%~3.39%）、고CaO（2.23%~3.68%）화고TiO2（0.05%~0.11%）위특정。미량원소상，우손희토원소（REE총량위1.73×10?6~4.63×10?6），우손불상용원소（여，Rb=0.4×10?6~1.39×10?6，Zr=0.73×10?6~3.28×10?6，Hf=0.04×10?6~0.11×10?6），부집상용원소（여，Cr=2516×10?6~2793×10?6，Co=84.6×10?6~119×10?6，Ni=1641×10?6~2261×10?6）。광물학화지구화학특정일치지시，오와문사록혼잡암중적초미철암위경력과저정도（5%~10%）부분용융작용적잔여지만감람암，형성우양중척배경，시MOR형사록암중적지만감람암。
The Wuwamen ophiolite is located on the southern margin of Middle Tianshan Mountains, Xinjiang. In this paper, petrology, mineralogy and geochemistry of the ultramafic rocks from Wuwamen ophiolite were studied to constrain their origin and tectonic setting. The ultramafic rocks from Wuwamen ophiolite are serpentinized lherzolites composed of olivine (Fo=89.1-90.6), orthopyroxene (Wo0.4-2.4En87.2~90.7Fs8.9-10.9;Mg#=89.0-91.0), clinopyroxene (Wo49.1-51.3En16.0~48.4Fs0.9-4.3;Mg#=90.2-92.1) and spinel (Mg#=71.8-77.5; Cr#=9.3-13.4). They are characterized by relatively lower content of MgO (37.74%-41.34%), and higher content of Al2O3 (2.58%-3.39%), CaO (2.23%-3.68%) and TiO2 (0.05%-0.11%). The ultramafic rocks are also depleted in rare earth elements (REE;total REE=1.73×10?6-4.63×10?6) and incompatible elements (e.g., Rb=0.4×10?6-1.39×10?6, Zr=0.73×10?6-3.28×10?6, Hf=0.04×10?6-0.11×10?6), and enriched in compatible elements (e.g., Cr=2516×10?6-2793×10?6, Co=84.6×10?6-119×10?6, Ni=1641×10?6-2261×10?6). These data indicate that the ultramafic rocks from Wuwamen ophiolite are residues of mantle rocks after low degrees (ca. 5%-10%) of partial melting in a Mid-Ocean-Ridge (MOR) environment.