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| 1 | Adakite-type sodium-rich rocks in Awulale Mountain of west Tianshan:Significance for the vertical growth of continental crust显示文摘The sodium-rich dacites and albite porphyries of Permian in the Awulale Mountain of west Tianshan have unique chemical and trace element signatures identical to adakite. These intermediate-acidic igneous rocks are characterized by high Na2O, Al2O3 and Sr contents and high Sr/Y and La/Y ratios (>40 and >20, respectively), and low Y and Yb contents, and strong depletion in HREE, and positive Eu anomaly. The (143Nd/144Nd)i is in the range from0.51236 to 0.51248 and the εNd(t) is positive value (+0.79-+3.11); the (87Sr/86Sr)i is in the range from 0.7052 to 0.7054. These Nd and Sr isotopic composition features indicate that the source rocks of these adakite-type rocks are from a weakly depleted mantle, or a depleted mantle, but was contaminated by the crustal materials. These adakite-type rocks were most likely derived from the partial melting of new underplated basaltic rocks under the conditions of amphibo-lite to eclogite transition in the postcollisional environment of North Xinjiang during the Permian | XIONG Xiaolin ZHAO Zhenhua BAI Zhenghua MEI Houjun WANG Yixian WANG Qiang XU Jifeng Niu Hecai BAO Zhiwei | 2001 | Chinese Science Bulletin2001，46，10： | 25 |
| 2 | Underplating in the middle-lower Yangtze Valley and model of geodynamic evolution:Constraints from geophysical data显示文摘The lower crust and Moho are the most active boundary layers in the process of continental evolution, in which marks left by tectonic and magmatic activities during the process are preserved. The evolutionary process of the continental lithosphere may be reconstructed by exploring the structures of the lower crust and Moho. According to a study of the deep seismic reflection data obtained from the middle-lower Yangtze Valley, the authors find bright layered reflections ubiquitous in the lower crust and think that the bright reflections are caused by un-derplating of basic or ultrabasic magmas, which might be related to delamination of the lithosphere. On the basis of an integrated analysis of the geophysical and geological data of the region, the authors propose a model for geodynamic evolution of the middle-lower Yangtze Valley. This model suggests that the middle-lower Yangtze Valley had undergone such geodynamic processes as collision-compression, delamination-extension and underplating-melting since the end of the Permian, finally forming the gigantic middle-lower Yangtze Valley metallogenic belt. | Lü Qingtian, HOU Zengqian, YANG Zhusen & SHI Danian Institute of Mineral Resources,Chinese Academy of Geological Sciences,Beijing 100037,China | 2005 | Science China Earth Sciences2005，48，7： | 24 |
| 3 | Petrogenesis and metallogenesis of the Yanshanian adakite-like rocks in the Eastern Yangtze Block显示文摘Many of the Yanshannian intermediate-acid intrusive rocks related to Cu-Au mineraliza-tion in the Eastern Yangtze Block are characterized by high AI2O3, Sr contents, while low in Y, Yb contents, thus with high Sr/Y, and La/Yb ratios, and variational isotope signatures in particular, e.g. εNd(t) = -11.92-1.96, (143Nd/144Nd): = 0.5120-0.5125, TDM= 0.70-1.71 Ga, (7Sr/86Sr), = 0.7043 -0.7076. The geochemical characteristics of these rocks suggest that: (1) these rocks are geo-chemically similar to adakite, which might have been stemmed from the partial melting of thick-ened basaltic lower crust due to basalt underplating; and (2) the high pressure (1.2-4.0 GPa) and high temperature (850-1150℃) surroundings of the lower crust favor both the fluid and ada-kite-like magma to generation. Not only can the adakite-like magma carry abundant fluid and Cu-Au ore-froming materials, but also can it bring them to the shallow part with ease and contrib-utes to the Cu-Au mineralization. | 王强 赵振华 许继峰 李献华 包志伟 熊小林 刘义茂 | 2003 | Science China Earth Sciences2003，46，z1： | 10 |
| 4 | Petrogenesis of Cenozoic Potassic Volcanic Rocks in the Nangqen Basin显示文摘The Nangqên basin is one of the Tertiary pull-apart basins situated in the east of the Qiangtang block. Similar to the adjacent Dengqên basin and Baxoi basin, there occurred a series of potassic volcanic and sub-volcanic rocks, ranging from basic, intermediate to intermediate-acid in lithology. Based on the study of petrology, mineralogy and geochemistry, including REEs, trace elements, isotopic elements and chronology, the authors concluded that the Cenozoic potassic volcanic rocks in the Nangqên basin were formed in the post-collisional intraplate tectonic settings. The relations between the basic, intermediate and intermediate-acid rocks are neither differentiation nor evolution, but instead the geochemical variability is mainly attributable to the different partial melting degrees of the mantle sources formed at depths of 50(80 km.The sources of the potassic rocks are enriched metasomatic mantle that has experienced multiple mixing of components mainly derived from the crust. The recycling model can be described as follows: after they had subducted to the mantle wedge, the crust-derived rocks were metasomatized with the mantle materials. In view of the fact that the ratio of crust-derived rocks increases by the age of volcanism, it can be concluded that the sources of the potassic rocks moved upwards progressively with time.The underplating of small scattered magmas upwelling from the asthenosphere may have induced partial melting of the sources of the volcanic rocks in some pull-apart basins in the Hengduanshan area and the intense tectonic movements of large-scale strike-slip belts provided conduits for the ascending melts. | SUN Hongjuan DENG Wanming ZHANG Yuquan | 2001 | Acta Geologica Sinica(English Edition)2001，75，1： | 4 |
| 5 | Contrasting Peridotite Types in the Dabie UHP Belt, Eastern China: the Raobazhai and Bixiling Ultramafic-mafic Complex显示文摘 The Dabie UHP metamorphic belt, central China,contains two contrasting types of mafic-ultramafic complex. The Bixiling peridotite in the southern Dabie terrane contains abundant garnet (21.1-32.2 vol% )and thus has high CaO + Al2O3 (9.81-15.9 wt% ).…… | Jianping Zheng Min Sun W. L. Griffin Mei-Fu Zhou Guochun Zhao | 2007 | 矿物岩石地球化学通报2007，26，z1： | 0 |
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