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Preliminary discussion of low-salinity hydrothermal fluid mineralization

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chinese Science Bulletin 1999年第S2期44卷 141-143页

作者： ZHENG Mianping R & D center of Saline Lake and Epithermal Deposits, chinese academy of geological sciences, beijing 100037,{3. R and D center of Saline Lake and Epithermal Deposits Chinese Academy of Geological Sciences Beijing 100037 China

REVIEWING the history of the geology of mineral deposits, we may find that in the first fifty years of thetwentieth century the magmatic-hydrothermal theory of ore deposition was the most prevalent, whichgave impetus to the development of the geology of mineral deposits. In the 1960s, the drilling of theSalton Sea geothermal field, California, the United States, and discovery and study of the Red Sea seafloor hot brines and large amounts of metal sulfides removed therefrom led to the rise of the brine theory ofmineral deposition, thus elucidating the origin of massive metal sulfides and promoted the discoveryand exploration of metal deposits. After the 1970s and the 1980s, through a study of the hydrothermal ore fluids of modern hotsprings. geologists came to realize that there exist low-salinity hydrothermal ore fluids other than

关键词： low-salinity hydrothermal fluid mineralization.

Mass Extinction——A Fundamental Indicator for Major Natural Divisions of geological History

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Acta Geologica Sinica(English Edition) 1988年第1期1卷 1-12页

作者： Xu Daoyi Zhang Qinwen Sun Yiyin institute of geology, State Seismological Bureau, beijing institute of geology,{3., beijing institute of geology, Academia Sinica, beijing institute of geology State Seismological Bureau Beijing China

In the Phanerozoic, there are three major geological boundaries: Precambrian/***/Triassic and Cretaceous/Tertiary. Studies of these boundaries in china and over the world stronglysuggest that they have the following similar features: mass extinctions of many taxa, positive anomalies ofplatinum-group metals, and abrupt changes of stable isotopes (δ13.). It is quite probable that these were theconsequences of some rare catastrophic events of extraterrestrial origin. Hence, the three above-mentionedmass extinction events may be regarded as key indicators for the division of the geological history of thePhanerozoic.

关键词： Mass Extinction A Fundamental Indicator for Major Natural Divisions of geological History

Geochemical characteristics and contemporary metallogenetic process of hot springs in Tengchong

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chinese Science Bulletin 1999年第S2期44卷 29-30页

作者： HU Yunzhong, WANG Haiping and ZHANG Tianle institute of Mineral Deposits, chinese academy of geological sciences, beijing 100037,{3. institute of Mineral Deposits Chinese Academy of Geological Sciences Beijing 100037 China

1 The Geochemical characteristics of hot spring systems THE characteristic element abundance value/concentration coefficients of the geochemical characteristics ofTengchong are: Au-6.10/4.07, As-7.13.3.96, Sb-1.25/6.23. Pb-3..87/2.47, Th-20.25/2.11, Cd-0.57/2.83. Li-40/2, Ti-1.3./2.89 (abundance unit: Au-1 × 10-9, the others-1 ×10-6 ). Generally, these 8 elements can reflect the characteristics of the metallogenetic process with magmatic hydrothermal activities in the area. The abundances of other 3. elements measured are similar tothose of the crust. Granite in the area belongs to the calc-poor granite. Compared with the granite abundance in theworld, Cr, Co, Th, Pb and Cd are the concentrated elements. Their change in the regional distributionshows that Ca, Na, Th, Zn and REE increase from north to south, but Mg, Ti, Ba, Cu, Li, V, Zr,

关键词： hot spring system hydrothermal activity contemporary metallogenetic process.

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 {3. of sciences, beijing 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

Experimental Observation of the Ore-Forming Fluid NaCl-H_2O System in the Earth Interior

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Acta Geologica Sinica(English Edition) 1999年第1期73卷 47-64页

作者： ZHANG Ronghua and HU Shumin Open Research Laboratory of Geochemical Kinetics, chinese academy of geological sciences,26 Baiwanzhuang Road, beijing 100037, china Open Research Laboratory of Geochemical Kinetics Chinese Academy of Geological Sciences 26 Baiwanzhuang Road Beijing 100037 China

The NaCl-H_2O binary system is a major component of solutions coexisting with ores. Observation ofsaturated solutions of NaCl-H_2O by using the method of hydrothermal diamond anvil cell (HDAC) is a new approach tothe study of ore-forming fluids. The salinities of NaCl-H_2O solutions in experimental observation are in a range of 3.-55%. The observed temperature range is 25℃-850℃, and the pressure range 1 atm-10 kb. In this temperature-pressure range, the supercritical single phase, two phases (L,V) close to the critical state and two-phased (L+V) immis-cible region were observed. And for the salinity of 3.% the two phase L+V immiscible region of NaCl-H_2O solutionwas observed in a range of 253.720℃. Another temperature range, 400-817℃, was observed for the immiscible two-phased region of 50% salinity solution. In the high-temperature part of the two-phased immiscible region, the phase na-ture is very unstable. A "critical phenomenon" was observed when the heating path was very close to the critical *** is possible to observe a 'critical phenomenon': an "explosion" occurred almost constantly at the interface between theliquid and vapour and the interface is rather obscure. A continuous transition between phases L and V could be foundin the immiscible L+V phase while heating continuously. Moreover, as the NaCl-H_2O solution was separated into liq-uid and vapour phases, static charges surrounding each vapour bubble could be seen, and these bubbles were attractedtogether by the static charges to form a special solution structure. Besides, critical states of different salinities of NaCl-H_2O were observed in order to study the properties of the fluids occurring in the rocks in the earth interior, the origin ofore-bearing fluids and the significance of supercritical fluid with respect to the ore formation. The comparison of the sa-linity data of the fluid inclusions in the minerals of ore deposits with observations of NaCl-H_2O under HDAC in theconditions of high temp

关键词： critical phenomenon solution structure of the two-phased immiscible region ore-forming hydrothermal solutions

Discovery of a pterodactylid pterosaur from the Yixian Formation of western Liaoning,china

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chinese Science Bulletin 2001年第13期46卷 1112-1117页

作者： WANG Xiaolin & LU Junchang1. institute of Vertebrate Paleontology and Paleoanthropology, chinese academy of {3., beijing 100044, china 2. College of Earth {3. and Resources, china University of Geo-{3., beijing 100083. china 3. Department of geological {3., Southern Methodist University, Dallas, TX 75275, USA institute of Vertebrate Paleontology Chinese Academy of Sciences Beijing 100044 China

A well-preserved pterosaur with nearly complete skull is described from the Lower Cretaceous Yixian Formation at Sihetun in western Liaoning. It is characterized by a low and long crestless skull, slender and pointed teeth, long metacarpal, nearly equal length of metatarsals I -III and short pedal digit V. It is referred to a new genus and species of the family Pterodactylidae: Haopterus gracilis gen. et sp. nov. This is the first pterosaur with a nearly complete skull from the Jehol Biota; it also represents the first non-controversial fossil record of Pterodactylidae in Asia. Haopterus is more derived than Pterodactylus from the Late Jurassic Solnhofen in Germany. This discovery extends the distribution of the family Pterodactylidae from Europe and Africa to Asia and its latest occurrence from the Late Jurassic to the Early Cretaceous. The discovery of Haopterus gracilis provides further evidence for the study of the originand radiation of the Jehol Biota; it also sheds new light on the evolution and

关键词： western Liaoning Early Cretaceous Yixian Formation Pterodactylidae.

The Early Evolution of the Acanthomorphic Acritarchs in china and Their Biostratigraphical Implication

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Acta Geologica Sinica(English Edition) 1996年第2期70卷 193-206,219-220页

作者： Yin Chongyu and Gao Linzhi institute of geology, chinese academy of geological sciences, beijing institute of geology Chinese Academy of Geological Sciences Beijing

On the basis of a study of the acanthomorphic acritarchs discovered in the Late Proterozoicto Early Cambrian Meishucunian Stage in different regions of china, especially in southernShaanxi and the Yangtze Platform, coupled with a study of the assemblages, morphological cor-relation, microstructure, and evolutional relations of the acanthorphic acritarchs, as well as awide correlation with those found in different regions of the world, the authors discuss the earlyevolutionary stages of the acanthomorphs, features of their assemblages in various stages, theirbiostratigraphical significance, and their evolutionary trend in china.

关键词： acanthomorphic acritarch Late Proterozoic evolutionary stage biostratigraphy

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 {3. of sciences,beijing 100029,china 1. Key Laboratory of the Earth’s Deep Interior Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 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

^(14)C measurement of forest soils in Dinghushan Biosphere Reserve

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chinese Science Bulletin 1999年第3期44卷 251-256页

作者： SHEN Chengde , LIU Dongsheng (LIU Tungsheng) , PENG Shaolin, SUN Yanmin , JIANG Mantao , Yl Weixi , XING Changping , GAO Quanzhou , LI Zhi’an and ZHOU Guoyi Guangzhou institute of Geochemisry, chinese academy of {3., Guangzhou 510640, china institute of geology, chinese academy of {3. , beijing 100029, china South china institute of Botany, chinese academy of {3., Guangzhou 510650, china Guannzhou institute of Geochemisry Chinese Academy of Sciences Guanazhou China institute of geology Chinese Academy of Sciences Beijing China South china institute of Botany Chinese Academy of Sciences Guangzhou China

Organic carbon in forest soils of Qingyunsi and Wukesong profiles can be divided into fast and slow components. Δ14C values of these profiles decrease with increasing of depth. The Δ14C values in 3.—40 cm depth interval of Wukesong profile are decreasing sharply until a very low value,showing that a strong geological environment change occurred about 1 560 years ago. The 14C apparent ages of Wukesong profile show that the coniferous and broad-leaf mixed forests around Wukesong profile have been developing since 425 a BP, which is consistent with historical documents. The penetrating depths of "bomb 14C" in Qingyunsi and Wukesong profiles are 10 and 20 cm, respectively.

关键词： Dinghushan forest soil 14C tracing 14C apparent age.