Petrogenesis of Huangbanjigou high magensiun andesite in Early Cretaceous Yixian Formation, western Liaoning

CORC > 南海海洋研究所 > 中国科学院南海海洋研究所 > 中科院边缘海地质重点实验室

	Petrogenesis of Huangbanjigou high magensiun andesite in Early Cretaceous Yixian Formation, western Liaoning
	Hong, LB; Zhang, YH; Ren, ZY; Xu, YG; Yan, W; honglubing110320@163.com; yigangxu@gig.ac.cn
刊名	ACTA PETROLOGICA SINICA
	2017
卷号	33 期号:1 页码:41-55
关键词	Olivine Melt Inclusion High Magnesium Andesite Crust-mantle Interaction Pyroxenite Huangbanjigou Western Liaoning
英文摘要	Olivine-hosted melt inclusions and their hosts, together with the bulk rocks were used to investigate the petrogenesis of the Huangbanjigou volcanic rocks in the Early Cretaceous Yixian Formation, western Liaoning Province. The Huangbanjigou volcanic rocks show the features of high magnesium andesite, such as SiO2 = 53. 41% similar to 53.74%, MgO = 8. 15%similar to 8.23%, Mg-# = 70 (Mg-# = mol Mg/(Mg + Fe2+)). They are sub-alkaline series, plating in the field of basaltic andesite in the TAS diagram. They also exhibit the characteristics of the mantle attributions, such as moderately high Ni (119 x 10(-6) similar to 125 x 10(-6)) and high Cr (467 x 10(-6) similar to 521 x 10(-6)). The Huangbanjigou high magnesium andesites have 920 x 10(-6) similar to 930 x 10(-6) Sr, 16. 1 x 10(-6) similar to 16. 4 x 10(-6) Y and 57 similar to 58 Sr/Y. In the mantle primitive-normalized spider diagram, the Huangbanjigou high magnesium andesites show fractionation from light to heavy rare earth elements, significant and slight negative anomalies of Nb-Ta-Ti and Zr-Hf,, respectively, and positive anomalies of BaSr-Pb; all these features resemble that of the continental lower crust. The olivine-hosted melt inclusions have 6. 5% similar to 9. 7% MgO and 51% 53% SiO2, unlike those of the typical high magnesium andesite. They are alkaline series, falling in the field of basaltic trachyandesite in the TAS plot. There are significant or slight negative relationships between MgO and other major element oxides, pointing to the olivine-controlled fractionation. Olivine crystals of the Huangbanjigou high magnesium andesites have Fo = 75 similar to 91, CaO = 0. 10%similar to 0. 18%, NiO = 0. 05%similar to 0. 41%, Fe/Mn = 60 similar to 80. There are large compositional discrepancies between the bulk rocks and the melt inclusions of the Huangbanjigou high magnesium andesites, such as the melt inclusions with higher Al2O3 and lower SiO2. Together with their similar trace element features to those of the continental lower crust, we suggest that the Huangbanjigou high magnesium andesites is the product of the crust-mantle interaction; they must assimilate an acid silicate melt from the lower crust during their magma evolution in the crust depth. We suggest that the mantle-derived melts of the Huangbanjigou andesites are the partial melts of the orthopyroxene-rich pyroxenite, on the basis of (1) relatively low Ni but high Me of the bulk rocks; (2) low CaO of the melt inclusions; (3) melt inclusion plotting in the SiO2-enriched side of the thermal divide boundary in the phase diagram of the CATS Olivine -Quartz; and (4) the olivine crystals with low Ca and steeper relationship between Fo and Ni. We argue that the widespread high magnesium andesites in the Early Cretaceous Yixian Formation, western Liaoning Province, likely underwent crust-mantle interaction; hence, they can not be considered as an important evidence of the delamination process resulting in the large scale thinning of the lithosphere.
资助项目	MSG
内容类型	期刊论文
源URL	[http://ir.scsio.ac.cn/handle/344004/16473]
专题	南海海洋研究所_中科院边缘海地质重点实验室
通讯作者	honglubing110320@163.com; yigangxu@gig.ac.cn
推荐引用方式 GB/T 7714	Hong, LB,Zhang, YH,Ren, ZY,et al. Petrogenesis of Huangbanjigou high magensiun andesite in Early Cretaceous Yixian Formation, western Liaoning[J]. ACTA PETROLOGICA SINICA,2017,33(1):41-55.
APA	Hong, LB.,Zhang, YH.,Ren, ZY.,Xu, YG.,Yan, W.,...&yigangxu@gig.ac.cn.(2017).Petrogenesis of Huangbanjigou high magensiun andesite in Early Cretaceous Yixian Formation, western Liaoning.ACTA PETROLOGICA SINICA,33(1),41-55.
MLA	Hong, LB,et al."Petrogenesis of Huangbanjigou high magensiun andesite in Early Cretaceous Yixian Formation, western Liaoning".ACTA PETROLOGICA SINICA 33.1(2017):41-55.