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Modelling adsorption of phosphate by soils while the solution concentration decreased with sorption

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Journal of Environmental Sciences 1998年第1期10卷 27-32页

作者： Sui Hong jian Research Center of Environment, Beijing Institute of Management, university of Science and Technology of China, Beijing 1014.8, China Rao Ji long department of geology and geophysics, Yale university

A mechanistic model developed by Barrow (1986) was modified to study the effect of time on adsorption of phosphate by soil when the solution concentration decreased with sorption. The model reproduced the effects of initial solution concentration, and of increasing time on the adsorption by 5 soils. Both the simulated and observed data showed that at low initial solution concentrations, phosphate in the solution decreased rapidly near to zero in a few hours or minutes. And the simulated results suggested that the rate of phosphate sorption by soils under the condition of the solution concentration decreased with sorption is much slower than that the solution concentration remains constant.

关键词： soil phosphate adsorption.

Volcanism and Tectonic Evolution in the North Qilian Mountains during Ordovician Period

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Journal of Earth Science 1998年第1期17卷 16-23页

作者： Lai Shaocong department of geology, Northwest university, Xi ’an 710069 Deng Jinfu Zhao Hailing department of geology, China university of Geosciences, Beijing 100083

The Ordovician marine volcanic rocks in the north Qilian mountains are discussed in this paper. According to geology, petrotectonic assemblage and geochemistry, a new model about plate tectonic evolution of the north Qilian mountains is set up. The Ordovician marine volcanic rocks in the north Qilian mountains which characterized by the geological features of tectonic melange of continent to continent collision underwent complicated tectonic movement, and can be classified into three main kinds of petrotectonic assemblages. During Ordovician period, north Qilian area was a polyisland ocean which consisted of three ocean basins separated by the middle microcontinental blocks.

关键词： volcanism petrotectonic assemblage tectonic evolution north Qilian.

STUDY ON METALLOGENIC COUPLEZONE(MCZ)DYNAMICS IN ZHEJIANG

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Journal of Central South university 1996年第1期8卷 25-28页

作者： Wang Dawei Zhang Jiachun(department of geology, Central South university of Technology,Changsha 4.0083, China) department of geology Central South University of Technology Changsha 410083 China

The authors first put forward the concept of metallogenic couplezone(MCZ) through the research on metallogenic zones in Zhejiang. Different features of the metal and nonmetal MCZ in Zhejiang are studied. MCZ model which is related to geodome and Diwa series is established. The author thinks that MCZ dynamic characteristic is related with crustobody dynamics, and controlled by magmatic, volcanic and structural activity zoning.

关键词： metallogenic couplezone dynamics Zhejiang

Histological observation of some primitive euconodonts of Late Cambrian from Liaoning

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Progress in Natural Science:Materials International 2005年第12期15卷 1084-1088页

作者： GUO Wei,DONG Xiping,ZENG Xiaochun and ZHAO Le department of geology,College of Environmental Science,Peking university,Beijing 100871,China department of geology College of Environmental Science Peking University Beijing 100871 China. College of Environmental Science Peking University Beijing 100871 China

The histology of some euconodonts of Late Cambrian from Benxi and Fuxian County,Liaoning Province is studied by the oil-immersion *** histological characteristics of six primitive species of euconodonts - Proconodontus muelleri,Proconodontus tenuiserratus,Granatodontus ani,Rotundoconus tricarinatus,Teridontus nakamurai and Cordylodus proavus are described in *** dentine and atubular (parallel- and wavy-lamellar) dentine are found in the basal bodies of the primitive euconodonts Proconodontus tenuiserratus and Proconodontus muelleri,*** tubular dentine and spherulitic dentine are also recognized from the basal bodies of Granatodontus ani and Rotundoconus *** the histological characteristics of the studied six species of euconodonts belonging to Proconodontus lineage and Teridontus lineage Sensu Miller (Univ Kansas Paleontol Contr,1980,99: 1-39) seems to be almost the same,euconodonts are proposed as possibly monophyletic herein.

关键词： histology primitive euconodonts Late Cambrian Liaoning

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Science China Earth Sciences 2004年第10期47卷 886-895页

作者： TANG Liangjie1,2, JIA Chengzao3, PI Xuejun4. CHEN Suping1,2, WANG Zhiyu5, XIE Huiwen4.1. Key Laboratory for Hydrocarbon Accumulation of Education Ministry, Beijing 10224., China 2. Basin & Reservoir Research Center, university of Petroleum, Beijing 10224., China 3. PetroChina Company Limited, Beijing 100011, China 4. Tarim Oilfield Company, PetroChina Company Ltd., Kurle 84.000, China 5. department of geology, university of Petroleum, Beijing 10224., China 1. Key Laboratory for Hydrocarbon Accumulation of Education Ministry 102249 Beijing China 2. Basin & Reservoir Research Center University of Petroleum 102249 Beijing China 3. PetroChina Company Limited 100011 Beijing China 4. Tarim Oilfield Company PetroChina Company Ltd. 841000 Kurle China 5. department of geology University of Petroleum 102249 Beijing China

The salt beds of Lower Tertiary developed in the mid-segment of Kuqa foreland fold belt, northern Tarim basin. They considerably controlled structural deformation of the belt. Ac- cording to the field observation, seismic profile interpretation and drilling data, three different structural styles of supra-salt, intra-salt and sub-salt occurred in the Kuqa foreland fold belt. Su- pra-salt structural styles mainly include thrust faults and fault-related sags. Intra-slat structural styles essentially are salt-pillows, intra-salt faults and folds, and salt weld structures. Sub-salt structural styles mainly consist of imbricated thrust faults, duplex structures, pop-up and fault-related folds. It is indicated that great differences exist among supra-salt, intra-salt and sub-salt structures of Kuqa foreland fold belt. The salt-related structures were formed in the same structural stress field. The dynamic mechanism of the salt-related structures is mainly associated with gravitation, compression and plastic flow of salt beds.

关键词： salt-related structural style, supra-salt structure, intra-salt structure, sub-salt structure, Kuga foreland fold belt.

Isotope Geological Studies of Granite-Type Uranium Deposits in South China

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Acta Geologica Sinica(English Edition) 1988年第3期1卷 291-305页

作者： Shen Weizhou Zhang Zuhuan Zheng Bangtong department of geology, Nanjing university, Nanjing, Jiangsu department of geology Nanjing University Nanjing Jiangsu

The uranium-bearing granites in South China can be classified into two types. namely, syntectic type andtransformation type. A fairly systematic hydrogen, oxygen. carbon, sulfur isotopic study of uranium depositsrelated to these two types of granites has been carried out by the authors, and the results show that they haveobvious differences in such aspects as ore-forming and rock-forming ages. properties of ore-forming solutionsand source of ore-forming substances. The authors hold that the uranium deposits related to the syntectic typegranitoids are intimately connected with magmatism in time and space, whereas the uranium deposits relatedto the transformation type granites, though spatially linked up with uranium-bearing granites, should actuallyowe their formation to extension in the fault block movement in South China.

关键词： In Isotope Geological Studies of Granite-Type Uranium Deposits in South China

LOCATING MECHANISM STUDY OF SEVERAL TYPES OF GOLD DEPOSITS

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Journal of Central South university 1996年第1期8卷 56-59页

作者： Li Peilan Yu Xingzhen(department of geology, Central South university of Technology,Changsha 4.0083, China) department of geology Central South University of Technology Changsha 410083 China

Based on the availabities of three orecontrolling factors, theauthors put forword the locating mechanism of gold deposits. The model experiment indicates that the pressurerelease effect occuring during the locating process marks the metallogenic nonlinear effect and causes the formation of deposits. In addition, the deposits involved in this paper can be divided into four kinds of locating mode.

关键词： gold deposit locating mechanism pressurerelease effect〖W

THE LUBRICATING MECHANISMS OF LUBRICATINGDRILLING FLUIDS ON SYNTHETIC DIAMOND BIT

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Journal of Central South university 1996年第1期8卷 87-89页

作者： Long Wei(department of geology, Central South university of Technology,Changsha 4.0083, China) department of geology Central South University of Technology Changsha 410083 China

The functions of lubricants in diamond drilling were discussedin this paper. The influences of lubricant on drilling efficiency and bit′s life were compared and analyzed with simulated drilling test and lubrication... 详细信息

关键词： lubricating drilling fluids diamond bit drilling pressure〖WT5BZ

TECTONIC SIGNIFICANCE OF THE WEST KUNLUN FOLD-THRUST-BELT AND THE TARIM SOUTHWEST DEPRESSION

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地学前缘 2000年第S1期7卷 84-86页

作者： Luo Jinhai (department of geology, Northwest university, Xi′an 710069,China)

The evolution of the Tarim southwest depression lying at the piedmont of the West Kunlun orogen differs completely from the evolution of the main part of Tarim basin after Later Palaeozoic because the former strongly subsides many times.. Subsidence is related closely to the West Kunlun fold thrust\|belt, thus the evolution of the Depression and the fold\|thrust\|belt reflects clearly the formation and evolution of the West Kunlun and even the Tibet.1 Evolution of the West Kunlun fold\|thrust\|belt\;Thrusting of the fold\|thrust\|belt can be classified into three stages:(1) Devonian thrusting:This is the oldest thrusting distinguished in the northern margin of the West Kunlun while the Silurian—Devonian thrusting was discriminated a few years ago by seismic data in the northern part of the East Kunlun. The Devonian thrusting is proved by the Upper Devonian dynamometamorphic rocks outcropping at the core of the anticline in the Sangzhu lying at the fold\|thrust\|belt. The rocks consist of slightly metamorphic clastic rock and have always been regarded as the Mid\|Proterozoic strata. But they are actually Upper Devonian strata according to the amount of perfect plant fossils that we found recently in the metamorphic rock, and they are overburdened `with an angular unconformity by another reliable Upper\|Devonian conglomerate in the core of the Aqike anticline. A possible explanation for this and its limited lined distribution parallel to the West Kunlun orogen is that they are subjected to metamorphism during the Later Devonian thrusting.

关键词： evolution West Kunlun fold\|thrust\|belt Tarim southw est depression correspondence