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The Discovery of Natural Native Uranium and Its Significance

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Acta Geologica Sinica(English Edition) 2015年第5期89卷 1561-1567页

作者： LI Ziying HUANG Zhizhang LI Xiuzhen GUO Jian FAN Chou Beijing research institute of Uranium geology South-Central University for Nationalities

This study analyzed the composition and uranium valence of pitchblendes sampled from the hydrothermal Guidong and Zhuguang uranium deposits of the middle Nanling metallogenic belt, Southern China using X-ray photoelectron spectroscopy（XPS）.A revolutionary discovery is that the uranium not only exists in the forms of tetravalent and hexavalent uranium oxides, but also occurs in the form of native *** is the first discovery of the existence of native uranium in *** greatly helps to reveal the origin of hydrothermal mineralization of uranium, and also has great significance for studying the thermal energy, formation and evolution of the earth.

关键词： pitchblende uranium deposit native uranium first discovery metallogenic origin

Zoning Patterns of Primary Halos and Their Controlling Factors in Porphyry Copper Deposits

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Acta Geochimica 1984年第3期3卷 195-205页

作者：黄书俊郦今敖傅金宝王建业 research institute of geology Ministry of Metallurgical Industry research institute of geology Ministry of Metallurgical Industry

The primary halos of porphyry copper deposits are characterized by compositional zoning inthree dimensions. Two ideal zoning patterns can be divided in accordance with the shape of pri-mary halos in space: bell-shaped and anticline-shaped. In the process of alteration-mineralization, K, Si, (OH), Fe, Cu, Mo, Ag, S, Ba, Rb, Pb,Zn, As, etc. were imported, while Na, Ca, Mg, Fe, Al, Ti, Mn, V, Co, Sr, Pb, Zn, etc. were ex-ported or became activated, and then transported and reprecipitated. Both import and export ofFe, Pb and Zn may have taken place. The fundamental factors controlling the zoning of primary halos are: the stability of comple-xes and the activity of elements; pH, Eh, the behaviour of sulfur and the sulphophile character ofelements; the concentration of components and the regularities of isomorphism; temperature andpressure; and tectonic setting and lithological characters of wallrocks. The authors consider that the zoning patterns of primary halos in porphyry copper depositsare the outcome of integrated effects of various factors.

关键词： Co Cu Zoning Patterns of Primary Halos and Their Controlling Factors in Porphyry Copper Deposits

research on the Application of the Light-Energy Spectrum Fusion Technique to Land and Resources Survey

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Acta Geologica Sinica(English Edition) 2000年第2期74卷 381-383页

作者： ZHAO Yingjun LIU Dechang Beijing research institute of Uranium geology Beijing 100029

This paper introduces how to use remote sensing images including Landsat (MSS and TM) and airborne radioactivity images to identify the type of rocks in the areas covered by vegetation. The relationship between light spectrum (Landsat MSS and TM) and energy spectrum (U, Th and K) is discussed on the basis of correlation analysis, and it is proven that there are correlations between the Landsat MSS or TM data and the U, Th and K data. By using the fusion technique, new images were generated, which contain both the light spectrum and the energy spectrum information.

关键词： light-energy spectrum fusion technique lithologic identification

Determination of specific activity of ^(230)Th in uranium ore samples

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Chinese Science Bulletin 2000年第3期45卷 264-267页

作者： ZHAO Yunlong, GU Dingxiang, LI Ronghui, DENG Gang, LIANG Yutang, WU Zhaohui, HUANG Qiuhong, TIAN Guiying, WANG Bin & CHEN CaifangBeijing research institute of Uranium geology, Beijing 100029, China Beijing research institute of Uranium geology Beijing China

A new method suitable for determining specific activity of 230Th in uranium ore samples is built. The method is characterized by adding the 230Th/ 232Th standard dilution agent with lower activity ratio (Its 230Th/ 232Th activity ratio and Th have been known) to the samples and using isotopic dilution analysis. The method can be applied to analyses of 230Th specific activity in various 230Th/ 232Th activity ratio samples. The precision can also be improved.

关键词： 230Th/ 232Th activity ratio 230Th specific activity activity ratio dilution analysis uranium ores.

Episodic sandstone-type uranium mineralization in Asia during the Late Mesozoic-Cenozoic

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Science China Earth Sciences 2023年第9期66卷 2034-2044页

作者： Chuang ZHANG Beijing research institute of Uranium geology China National Nuclear CorporationBeijing 100029China

Sandstone-type uranium deposits(STUDs) are the most important global source of uranium. However, it is unclear why STUDs have a non-random distribution in time and space. It is generally thought that STUDs are formed by the circulation of groundwater in sandstone rocks. The groundwater is typically oxidized and sourced from local precipitation, which suggests the regional climate may have a role in the formation of STUDs. The groundwater circulation is mainly affected by basin evolution, which means that regional tectonism may also control the formation of STUDs. In this study, the author examined STUDs in Asia, and compiled previously reported ages for STUDs and compared these with the uplift history of the major orehosting regions and the late Mesozoic–Cenozoic climatic evolution of Asia. Apart from a few uranium deposits in the Transural region, most of the STUDs in Asia were formed during the Late Cretaceous to Quaternary, and can be classified into three stages:Late Cretaceous–early Paleogene(80–50 Ma;stage I), Oligocene–mid-Miocene(25–17 Ma;stage Ⅱ), and late Miocene–present(8–0 Ma;stage Ⅲ). The formation of STUDs in Asia was closely related to regional uplift caused by India–Eurasia collision,subduction of oceanic plates, and increased humidity during greenhouse climate periods and intensification of the Asian Monsoon.

关键词： Sandstone type uranium deposits India-Eurasia collision Asian monsoon system Asian Westerlies

Haitaite-(La),LaU^(4+)Fe^(3+)2(Ti_(13)Fe^(2+)_(4)Fe^(3+))_(Σ18)O_(38),a New Member of the Crichtonite Group

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Acta Geologica Sinica(English Edition) 2022年第6期96卷 2007-2014页

作者： WANG Fenggang FAN Guang LI Ting GE Xiangkun WU Yu WANG Tao YAO Jian Beijing research institute of Uranium geology Beijing 100029China research institute 280 CNNCGuanghanSichuan 618300China

Haitaite-(La),(La,Ce)(U^(4+),U6^(+),Fe^(2+))(Fe^(3+),Al)2(Ti,Fe^(2+),Fe^(3+))18O38,is a new member of the crichtonite *** is named after the Haita Village in the Miyi County of Sichuan Province,China,where the mineral was *** mineral occurs as black opaque centimeter-sized aggregates in the external contact zone between the Neoproterozoic(~800 Ma)alkali feldspar granite and the Mesoproterozoic(~1700 Ma)*** the studied sample,haitaite-(La)is associated with other minerals,including ilmenite,magnetite,rutile,zircon,brannerite and *** new mineral is a black,metallic phase and has a Mohs hardness of 6,with a density of 4.99 g/cm3(calculated)and 5.03 g/cm^(3)(measured).Haitaite-(La)is opaque in transmitted light and grayish-white under reflected light,with a reflectivity between 22.5%and 16.42%in the 400–700 nm band(SiC,in the air).The compositions of the mineral were measured by EPMA,the U4+/U6+ratio was determined by X-ray photoelectron spectroscopy and the Fe^(2+)/Fe^(3+)ratio was determined by Mössbauer ***-(La)is trigonal,belongs to R3¯and has unit-cell parameters a=10.3678(5)Å,c=20.8390(11)Å,V=1939.9(2)Å3,Z=*** crystalline structure is composed of octahedra with 9 layers of close-packed octahedra(M1,M3,M4,M5),tetrahedra(M2)and contains large 12-coordinated M0 sites.

关键词： Haitaite-(La) new mineral crichtonite group crystalline structure U-Ti-LREE mineral

Control of coupling among three major factors for formation of high-efficiency gas reservoir——A case study on the oolitic beach gas reservoir in Feixianguan Formation in the northeast Sichuan Basin

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Chinese Science Bulletin 2007年第A01期52卷 201-214页

作者： WANG ZeCheng ZHAO WenZhi ZHANG ShuiChang WANG HongJun YU Qian institute of geology Research Institute of Petroleum Exploration and Development Beijing 100083 China research institute of Petroleum Exploration and Development Beijing 100083 China Testing Center of Petroleum geology Research Institute of Petroleum Exploration and Development Beijing 100083 China Chengdu institute of geology and Mineral Resources Chengdu 610082 China

Through a case study of the high-efficiency gas reservoir in Feixianguan Formation in the northeast Sichuan Basin, quantitative and semi-quantitative analyses of key elements such as hydrocarbon generation, migration and accumulation, and reservoir evolution as well as their interplay in the critical moment of reservoir formation controlled by the energy field were carried out, by means of numerical modeling of the energy field. It was found that the climax time for Permian hydrocarbon generation was Late Triassic-Early Jurassic and accumulation of oil and gas has resulted in large-scale paleoreservoirs in paleostructural traps in Feixianguan Formation, a process facilitated by fractures connecting the sources. The paleoreservoirs have been turned into high-efficiency gas kitchens due to pyrolysis, which resulted from deep burial at a temperature of 170―210 ℃ as induced by tremendously thick sedimentation in the foreland basin of Daba Mountain in Late Jurassic-Cretaceous period. Meanwhile, abundant acid gas like H2S produced from thermo-chemical sulfate reduction (TSR) at high temperatures leads to extensive dissolution of dolostone in the paleoreservoirs, which may in turn result in modification of the reservoirs and preservation of the reservoir rock porosity. The present distribution of gas reservoirs was ultimately determined in the processes of adjustment, cooling and decompression of the paleoreservoirs resulting from intense deformation in the front of Daba Mountain during the Himalayan orogeny.

关键词：数字模型高效率储存四川盆地资源开发

Longitudinal distributions of two formation pathways of biogenic gases in continental deposits: A case study from Sebei 1 gas field in the Qaidam Basin, western China

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Science China Earth Sciences 2007年第2期50卷 221-227页

作者： SHUAI YanHua ZHANG ShuiChang ZHAO WenZhi SU AiGuo WANG HuiTong Petroleum geology research and Central Laboratory Research Institute of Petroleum Exploration and DevelopmentBeijing 100083China

The distribution of two formation pathways of biogenic methane, acetate fermentation and reduction of CO2, has been extensively studied. In general, CO2 reduction is the dominate pathway in marine envi- ronment where acetate is relatively depleted because of SRB consuming. While in terrestrial freshwater or brackish environment, acetate fermentation is initially significant, but decreases with increasing buried depth. In this paper, character of biogenic gases is profiled in the XS3-4 well of the Sebei 1 gas field in the Sanhu depression, Qaidam Basin. It indicates that those two pathways do not change strictly with increasing buried depth. CO2 reduction is important near the surface (between 50 m and 160 m), and at the mesozone (between 400 and 1650 m). While acetate fermentation is the primary pathway at two zones, from 160 to 400 m and from 1650 to 1700 m. δ 13C of methane generated in those two acetate fermentation zones varies greatly, owing to different sediment circumstances. At the sec- ond zone (160-400 m), δ 13C1 ranges from ?65‰ to ?30‰ (PDB), because the main deposit is mudstone and makes the circumstance confined. At the fourth zone of the well bottom (1650-1700 m), δ 13C1 is lighter than ?65‰ (PDB). Because the deposit is mainly composed of siltstone, it well connects with outer fertile groundwater and abundant nutrition has supplied into this open system. The high con- centration of acetate is a forceful proof. δ 13C of methane would not turn heavier during fermentation, owing to enough nutrition supply. In spite of multi-occurrence of acetate fermentation, the commercial gas accumulation is dominated by methane of CO2-reduction pathway. A certain content of alkene gases in the biogenic gases suggests that methanogensis is still active at present.

关键词： biogenic gases carbon dioxide carbon isotopes hydrogen isotopes Qaidam Basin

Discovery and Significance of Malan Loess on the Piedmont Plain in Pinggu District, Beijing

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Acta Geologica Sinica(English Edition) 2014年第5期88卷 1565-1578页

作者： LU Lu ZHAO Yuanyi WANG Xiaoliang ZHAO Xitao YANG Zhenjing WANG Chengmin BI Zhiwei LU Wenhui institute of Mineral Resources Chinese Academy of Geological Sciences Beijing institute of geology Liaoning institute of geology and Mineral Resources institute of geology and Geophysics Chinese Academy of Sciences institute of Hydrogeology and Environmental geology Chinese Academy of Geological Sciences No.3 geology and Mineral Exploration institute of Gansu Provincial Bureau of geology and Mineral

The platforms on both sides of the Malangou River （a lateral ditch of the Qingshui River that is a tributary of the Yongding River） where Malan Village in Zhaitang Town of Mentougou District of Beijing is located are the place of China＇s typical section of the Quaternary Malan loess. During the investigation in the eastern suburbs of Beijing City, the authors not only clarified 5 grades of terraces on the Pinggu piedmont plain, but also found a clayey silt section mixed with a small amount of alluvial-diluvial gravel layers at a height of 15-25 m above the river level near a Fishpond in Xinli Village of Nandule Town. Results of the study of grain size of the section document that the loess mostly is silty soil （0.05--0.005 mm）, and that the grain size probability cumulative curves of the section are dominated by single-peak, coarse-grained segment I and coarse-grained segment II types, reflecting that its depositional environment is similar to eolian phase. Identification results of heavy minerals from the section show that their contents account for 0.01%-0.11%, averaging 0.04%. There are 24 kinds of heavy minerals, most of which are stable heavy minerals, and the clay minerals mostly are illite, which is consistent with the Malan loess on the Loess Plateau. The chemical composition data reflect that the source area of the loess is relatively arid. The six grade classification of sporopollen in the section further shows the subdivision of the history of alternating warm and humid phases in this geological period. The thermoluminescence dating results range from 21.0 ka to 59.2 ka, convincingly demonstrating that the section indeed consists of Malan loess. The above studies provide a new basis for overall understanding of the distribution of the Malan loess at the northeast margin of the North China Plain and its environment change in the Late Pleistocene.

关键词： eolian loess Malan loess formation environment Pinggu