|
|
|
题名
|
作者
|
年代
|
出处
|
被引量
|
| 1 | Zircon U-Pb and geochemical analyses for leucocratic intrusive rocks in pillow lavas in the Danfeng Group,north Qinling Mountains,China显示文摘Field observation showed that there are many irregular leucocratic intrusive rocks in pillow lavas in the Danfeng Group in the Xiaowangjian area, north Qinling orogenic belt. Photomicrographs indicated that the protoliths of those altered leucocratic intrusive rocks are dioritic rocks. Geochemical analyses showed that pillow lavas have a range of SiO2 from 47.35% to 51.20%, low abundance of TiO2 from 0.97% to 1.72%, and percentages of MgO (MgO#=41―49). Chondrite-normalized REE patterns of pillow lavas are even, indicative of a weak differentiation between LREE and HREE (La/YbN=1.52―0.99). N-MORB-normalized trace element abundances showed that pillow lavas are enriched in incompatible elements (e.g., K, Rb, and Ba). Leucocratic intrusive rocks in pillow lavas have a wide range of SiO2 from 53.85%―67.20%, low abundances of TiO2 from 0.51%―1.10%, and MgO (MgO#=40―51), and higher percentages of Al2O3 (13.32%―16.62%) and concentration of Sr (342-539 μg/g), ratios of Na2O/K2O (2―7) and Sr/Y (17―28). Chondrite-normalized REE patterns of leucocratic intrusive rocks showed highly differentiation between LREE and HREE (La/YbN=12.26―19.41). N-MORB-normalized trace element abundances showed that leucocratic intrusive rocks are enriched in incompatible elements (e.g., K, Rb, and Ba), and significantly depleted in HFSE (e.g., Nb, Ta, Zr and Ti), indicative of a relationship to subduction. Isotopically, leucocratic intrusive rocks have a similar εNd(t) (+7.45―+13.14) to that of MORB (+8.8―+9.7), which indicates that those leucocratic intrusive rocks sourced from depleted mantle most likely. SHRIMP U-Pb analyses for zircon showed that those leucocratic intrusive rocks were formed at 442±7 Ma, yielding an age of subduction in the early Paleozoic in the north Qinling orogenic belt. | Yan QuanRen Chen JunLu Wang ZongQi Yan Zhen Wang Tao Li QiuGen Zhang ZongQing Jiang ChunFa | 2008 | Science China Earth Sciences2008，51，2： | 14 |
| 2 | The geochemical characteristics,geochronology and tectonic significance of the Carboniferous volcanic rocks of the Santanghu area in northeastern Xinjiang,China显示文摘The Santanghu area is located on the northeastern margin of the Junggar Basin,northern Xinjiang,Northwest China.The Carboniferous volcanic rocks in this area are widely distributed in Kaokesaiergaishan,Santanghu,Daheishan and Naomaohu districts,which are located to the north of the Kalameili Fault.These rocks,sourced from a cognate magma,consist of basic,intermediate,and acidic lavas,and pyroclastic rock.The basic volcanic rocks are enriched with large-ion lithophile elements(LILE),but are relatively depleted in high field strength elements(HFSE),and have an obvious negative Nb-Ta-Ti anomaly.They were most probably derived from a depleted mantle source,and during their ascent,these magmas were not contaminated by the crustal material as they underwent magma crystallization differentiation.Based on the Carboniferous volcanic assemblage and geochemical data,it is apparent that the early Carboniferous volcanism occurred in a subduction-related tectonic setting.New LA-ICP-MS zircon U-Pb analyses constrain the age of the andesite within the volcanic rocks as the early Carboniferous(328.9-331.3 Ma).Combined with the regional geological record,comprehensive analysis of the isotope geochronological data indicates that the subduction of the Junggar Ocean predates the early Carboniferous,and that the Santanghu island arc magmatism was induced by the subduction of the Junggar Ocean in the Carboniferous. | LI Wei LIU YiQun DONG YunPeng ZHOU XiaoHu LIU XiaoMing LI Hong FAN TingTing ZHOU DingWu XU XueYi CHEN JunLu | 2013 | Science China Earth Sciences2013，56，8： | 8 |
| 3 | Geochemistry, geochronology and Hf isotope of granitoids in the Chinese Altai: Implications for Paleozoic tectonic evolution of the Central Asian Orogenic Belt显示文摘The Chinese Altai in northwestern Xinjiang has numerous outcrops of granitoids which provide critical information on accretionary orogenic processes and crustal growth of the Central Asian Orogenic Belt.Zircon U-Pb ages, Hf-isotopic compositions and whole-rock geochemistry of monzogranite and granodiorites in the Qinghe County are employed to elucidate Paleozoic tectonics of the Chinese Altai. Granodiorites have crystallization ages of 424.6 ± 3.1 Ma(MSWD = 0.23) and 404.0 ± 3.4 Ma(MSWD = 0.18);monzogranite was emplaced in the early Permian with a crystallization age of 293.7 ± 4.6 Ma(MSWD = 1.06). Both granodiorites and monzogranite are I-type granites with A/CNK ratios of 0.92 -0.97 and 1.03 -1.06, respectively. They also show similar geochemical features of high HREE and Y contents, low Sr contents and Sr/Y ratios, as well as enrichment of Cs, Rb, Th and U, and depletion of Nb, Ta, P and Ti.These geochemical features indicate that the monzogranite and granodiorites were formed in an arc setting related to subduction. The gneissic monzogranites display high SiO_2 and K_2 O contents, and belong to the high-K calc-alkaline series. In the chondrite normalized REE distribution pattern, the monzogranite samples exhibit enrichment of LREE with strong negative Eu anomalies(σE u =0.44 -0.53), zircon εHf(t) values from +7.24 to +12.63 and two-stage Hf model ages of 463 -740 Ma. This suggests that the monzogranite was generated from the mixing of pelitic and mantle material. The granodiorite samples are calc-alkaline granites with lower contents of Si O_2 and Na_2 O + K_2 O, higher contents of TiO_2, Fe_2O_3~t, MgO and CaO compared to the monzogranite samples. They also show enrichment of LREE and moderate negative Eu anomalies(σE u= 0.54 =0.81), as well as slightly higher differentiation of LREE than that of HREE. The425 Ma granodiorite has zircon εHf(t) values from -0.51 to +1.98 and two-stage Hf model ages of 1133 -1240 Ma, whereas the 404 Ma granodiorite displays those of +2.52 to +7.50 and 816 -1071 Ma.Geochemistry and zircon Hf isotopic compositions indicate that granodiorites were formed by partial melting of juvenile lower crust. Together with regional geology and previous data, the geochemical and geochronological data of the monzogranite and granodiorites from this study suggest long-lived subduction and accretion along the Altai Orogen during ca. 425 -294 Ma. | Dengfeng He Yunpeng Dong Xueyi Xu Junlu Chen Xiaoming Liu Wei Li Xiangmin Li | 2018 | Geoscience Frontiers2018，9，5： | 3 |
| 4 | Devonian Sedimentary Environments and Provenance of the Qinling Orogen: Constraints on Late Paleozoic Southward Accretionary Tectonics of the North China Craton显示文摘 | Zhen Yan Zongqi Wang Quanren Yan Tao Wang Wenjiao Xiao Jiliang Li Fanglin Han Junlu Chen Yongcheng Yang | 2006 | International Geology Review2006，，7： | 1 |
| 5 | Ultra-sensitive flexible Ga_(2)O_(3)solar-blind photodetector array realized via ultra-thin absorbing medium显示文摘The quest for solar-blind photodetectors with outstanding optoelectronic properties and weak signals detection capability is essential for their applications in the field of imaging,communication,warning,etc.To date,Ga_(2)O_(3)has demonstrated potential for high-performance solar-blind photodetectors.However,the performance usually decays superlinearly at low light intensities due to carrier-trapping effect,which limits the weak signal detection capability of Ga_(2)O_(3)photodetectors.Herein,a Ga_(2)O_(3)solarblind photodetector with ultra-thin absorbing medium has been designed to restrain trapping of photo-generated carriers during the transporting process by shortening the carrier transport distance.Meanwhile,multiple-beam interference is employed to enhance the absorption efficiency of the Ga_(2)O_(3)layer using an Al/Al_(2)O_(3)/Ga_(2)O_(3)structure.Based on the ultra-thin absorbing medium with enhanced absorption efficiency,a 7×7 flexible photodetector array is developed,and the detectivity can reach 1.7×10^(15)Jones,which is among the best values ever reported for Ga_(2)O_(3)photodetectors.Notably,the performance of the photodetector decays little as the illumination intensity is as weak as 5 nW/cm2,revealing the capacity to detect ultra-weak signals.In addition,the flexible photodetector array can execute the functions of imaging,spatial distribution of light source intensity,real-time light trajectory detection,etc.Our results may provide a route to high-performance solar-blind photodetectors for ultra-weak light detection. | Yancheng Chen Xun Yang Yuan Zhang Xuexia Chen Junlu Sun Zhiyang Xu Kaiyong Li Lin Dong Chongxin Shan | 2022 | Nano Research2022，15，4： | 1 |
| 6 | Carotid atherosclerosis,intima media thickness and risk factors-an analysis of 1781 asymptomatic subjects in TaiWan显示文摘 | Yu Sun Cheng HuaLin Chen JunLu | 2002 | Atherosclerosis2002，164，： | 1 |
| 7 | Thoughts on Building China-Japan Strategic Relations of Mutual Benefit显示文摘In the recent two years, leaders of China andJapan have successively exchanged visits dubbedrespectively as 'ice-breaking', | Chen Duming Zheng Junlu | 2008 | International Understanding2008，，1： | 0 |
| 8 | Cause and Impact of the Financial Crisis in the United States显示文摘The current round of financial crisis stemming from the U.S. is now spreading rapidly all over the world.People are yet to see what will become of the crisis.There are entrenched reasons for the crisis. | Chen Ying Zheng Junlu | 2008 | International Understanding2008，，4： | 0 |
您所在的机构暂未开通此部分的功能，请联系管理员