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Mantle-derived rare-gas releasing features at the Tianchi volcanic area, Changbaishan Mountains

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chinese Science Bulletin 1997年第9期42卷 768-771页

作者： SHANGGUAN Zhiguan and SUN Mingliang1. institute of geology, State Seismological Bureau,{2., China 2. Lanzhou institute of geology, chinese academy of sciences, Lanzhou 730000, China institute of geology State Seismological Bureau Beijing China Lanzhou institute of geology Chinese Academy of Sciences Lanzhou China

TIANCHI volcano,Changbaishan Mountains isthe largest modern active volcano in East *** times strong volcanic erupting activ-ities occurred in the Cenozoic *** vol-canic activities have revived again in the *** investi... 详细信息

关键词： Tianchi volcanic area Changbaishan Mountains mantle-derived rare gas 3He/ 4He 40 Ar/36 Ar 4He/2. Ne 4He/40Ar isotope ratios.

Ambient noise near the sea-route

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Science China(Physics,Mechanics & Astronomy) 2009年第1期52卷 40-45页

作者： HE Li1,2. LI ZhengLin1,3 & PENG ZhaoHui1 1 National Laboratory of Acoustics, institute of Acoustics, chinese academy of sciences,{2. 100190, China 2.institute of geology and geophysics, chinese academy of sciences, beijing 10002., China 3 NanHai Laboratory of Acoustics, institute of Acoustics, chinese academy of sciences, Haikou 5702.6, China National Laboratory of Acoustics Institute of Acoustics Chinese Academy of Sciences Beijing China institute of geology and geophysics Chinese Academy of Sciences Beijing China NanHai Laboratory of Acoustics Institute of Acoustics Chinese Academy of Sciences Haikou China

Ambient noise data measured in an experiment conducted in shallow water near a sea-route were analyzed. It was observed that, at low frequency, the horizontal correlation has an obvious difference from that predicted by the classical ambient noise model. The theoretical analyses show that this phenomenon is caused by wind noise together with the discrete shipping noise nearby. An ambient noise model was proposed to include the effects caused by both the noise sources. Data measured at different times verify that the proposed model can be used to forecast the ambient noise field in shallow water near the sea-route.

关键词： ambient noise model horizontal correlation discrete ships

Origin, Evolution and Mechanism of the Jehol Fauna

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Acta Geologica Sinica(English Edition) 1991年第2期65卷 203-215页

作者： Wang Si’en institute of geology,{2. academy of Geological sciences, beijing Liu Linqun institute of geology Chinese Academy of Geological Sciences Beijing

This paper deals with the geographic distribution and geological setting of the Jehol (northeastHebei-southwest Liaoning-southeast Inner Mongolia) fauna, and discusses the origination and the evolution ofits major biological groups. It is demonstrated that the Yan-Liao (northern Hebei-western Liaoning) area is theprovenance for the fauna. Why the fauna originated and developed in the area was intimately related to suchfactors as the palaeoclimate, palaeogeography, crustal movement, volcanism and frequent reversals of magnet-ic polarity at that time, in addition to the internal factors of the organisms themselves.

关键词： Origin Evolution and Mechanism of the Jehol Fauna

Ore-forming fluid and mineralization of Caijiaying and Dajing polymetallic ore deposits

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Science China Earth sciences 2004年第2期47卷 97-107页

作者： WANG Lijuan,WANG Jingbin, WANG Yuwang & ZHU Heping1. Key Laboratory of Mineral Resources, institute of geology and geophysics, chinese academy of sciences,{2., China 2. beijing institute of geology for Mineral Resources, beijing 100012. China Correspondence should be addressed to Wang Lijuan (email: wlj@***) Key Laboratory of Mineral Resources Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China beijing institute of{2. for Mineral Resources Beijing China

Fluid inclusions from the Dajing and Caijiaying deposits have nearly the same homogenization temperature. Correlation between temperature and salinity shows that both Sn- and Cu-bearing fluids Sn and Cu were present in the Dajing deposit but only one kind of fluids continuously evolved in the Caijiaying deposit. Study on rare earth elements (REE) in ancient fluid from the inclusions indicates that the fluid of Sn mineralizing stage in Dajing was derived from remelting magma of the continental crust, and the fluid of Cu-Pb-Zn mineralizing stage in the Dajing deposit and the fluid of Cu-Pb-Zn mineralization in the Caijiaying deposit were derived from the mantle. It is concluded that the Cu-Pb-Zn mineralizations in the Dajing and Caijiaying deposits resulted from the identical tectono-thermal event of magma-fluids induced by Mesozoic tectonic transition and extension in the eastern part of North China Craton.

关键词： Caijiaying, Dajing, Mesozoic tectonic transition, ore-forming fluid, REE.

Typical basin-fill sequences and basin migration in Yanshan, North China ——Response to Mesozoic tectonic transition

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Science China Earth sciences 2004年第2期47卷 181-192页

作者： LI Zhong, LIU Shaofeng, ZHANG Jinfang & WANG Qingchen1. institute of geology and geophysics, chinese academy of sciences,{2., China 2. China University of Geosciences, beijing 100083, ChinaCorrespondence should be addressed to Li Zhong (email: lizhongd@***) institute of geology and geophysics Chinese Academy of Sciences Beijing China China University of Geosciences Beijing China

Basin-fill sequences of Mesozoic typical basins in the Yanshan area, North China may be divided into four phases, reflecting lithosphere tectonic evolution from flexure (T3), flexure with weak rifting (J1+2., tectonic transition (J3), and rifting (K). Except the first phase, the other three phases all start with lava and volcaniclastic rocks, and end with thick coarse clastic rocks and/or conglomerates, showing cyclic basin development rather than simple cyclic rift mechanism and disciplinary basin-stress change from extension to compression in each phase. Prototype basin analysis, based on basin-fill sequences, paleocurrent distribution and depositional systems, shows that single basin-strike and structural-line direction controlling basin development had evidently changed from east-west to northeast in Late Jurassic in the Yanshan area, although basin group still occurred in east-west zonal distribution. Till Early Cretaceous, main structural-line strike controlling basins just turned to northeast by north in the studied area.

关键词： Yanshan, Mesozoic, basin-fill, paleocurrent, tectonic transition.

Quantitative assessment of the complexity of geological structures in terms of seismic propagators

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Science China Earth sciences 2010年第1期53卷 54-63页

作者： FU LiYun Key Laboratory of the Earth’s Deep Interior,institute of geology and geophysics,chinese{2. of sciences,beijing 10002.,China Key Laboratory of the Earth’s Deep Interior Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China

How a wave interacts with heterogeneous media has been pursued by many *** complexity of subsurface heterogeneities is seismologically a relative concept to wavelengths of seismic waves.A growing perception is that velocity variations,propagation angles,and computational accuracies are closely related at a variety of scales.A tentative strategy to quantitatively evaluate the complexity of subsurface heterogeneous media is presented in this article to see what scales of geological heterogeneities to be captured by *** express complex subsurface structures as the slowness-and angularheterogeneity spectra to quantify velocity contrasts and dipping-angle distributions of complex geological *** the other hand,the scaling characteristics of a propagator are measured through dispersion analysis by its angular spectra plotted against refractive indexes and propagation angles,respectively.A parameter termed as imaging efficiency is introduced by associating the geological heterogeneity spectra with the propagator's angular spectra to understand the coherent interference between the medium's heterogeneity and the propagator's scaling ***,a complexity coefficient can be defined to evaluate geological complexities in terms of *** application of this strategy is demonstrated to the SEG/EAEG salt model.

关键词： geological heterogeneity spectra seismic imaging propagator’s angular spectra imaging efficiency complexity coefficient

Isotopic feature and uranium dating of the volcanic rocks in the Okinawa Trough

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中国科学：地球科学英文版 2006年第4期49卷 375-383页

作者： HUANG Peng1,2. LI Anchun1, HU Ningjing2.3, FU Yongtao1& MA Zhibang4 1. institute of Oceanology, chinese academy of sciences, Qingdao 2.6071, China 2. Graduate School of the chinese academy of sciences, beijing 100039, China 3. institute of Soil Science, chinese academy of sciences, Nanjing 2.0008, China 4. institute of geology and geophysics, chinese academy of sciences, beijing 10002., China institute of Oceanology Chinese Academy of Sciences Qingdao China Graduate School of the chinese academy of sciences Beijing China institute of Soil Science Chinese Academy of Sciences Nanjing China institute of geology and geophysics Chinese Academy of Sciences Beijing China

Volcanic rocks from the northern and middle Okinawa Trough were dated by ura- nium-series dating method. Differential fractions using magnetic procedure were designed to separate samples. New report on the ages and isotopic data of rocks in the northern trough (especially black pumice) was discussed. Based on the uranium dates and Sr-Nd isotopic ratio, magmatic evolution process of the Okinawa Trough was noted. Firstly, there have been wide silicic volcanic activities in the Okinawa Trough from late Pleistocene to present, and the volcanic rocks can be divided into three subgroups. Secondly, magma generally came from PREMA source area under the Okinawa Trough. Magmatic evolution in the northern trough was similar to the middle, but different to the south. Finally, volcanic activities indicated that opening of the southern Okinawa Trough did not happen due to the collision between Luson Arc and Eurasian Plate until the early Pleistocene.

关键词： Okinawa Trough, black pumice, uranium-series dating, Sr-Nd isotopic ratio, magmatic evolution.

Searching for the remains of subducted continental slabs

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chinese Science Bulletin 2000年第5期45卷 385-386页

作者： LIU Guangdinginstitute of geology and geophysics, chinese academy of sciences,{2. 100101, China institute of geology and geophysics Chinese Academy of Sciences Beijing China

On the basis of oceanic geological and geophysical observations the global plate tectonics theory wasput forward in the late 1960s. It inherited the essence of mobilism of continental drift and sea-floorspreading, caused a revolution of earth sciences in the twentieth century. But plate tectonics cannotsatisfactorily explain the complicated geological phenomena of continents, it fails in elucidating

关键词： Searching for the remains of subducted continental slabs der Nature

δD values of escaped H_2.from hot springs at the Tengchong Rehai geothermal area and its origin

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chinese Science Bulletin 2002年第2期47卷 146-149页

作者： SHANGGUAN Zhiguan & HUO Weiguo institute of geology, China Seismological Bureau,{2., China institute of geology and geophysics, chinese academy of sciences,{2., China institute of geology China Seismological Bureau Beijing 100029 China

Here we give the δD values of escaped H2.from hot springs at the Tengchong Rehai and adjacent regions, and deal with a genetic correlation between the increment H2.in escaped gases from middle-shallow reservoirs and the H2., CH4 derived from deep sources. Isotopic compositions of H2.indicate that the generation of increment H2.may be related to recent strong activity of N-W trending fault at the Rehai area. Trace monitoring the H2.release could be significant in order to keep watch on present activity of that fault.

关键词： Rehai geothermal area hydrogen stable isotopic composition.