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Geochemical and isotopic imprints of hydrodynamic environments of fissure waters in crystalline rocks

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Chinese Science Bulletin 1997年第9期42卷 756-761页

作者： WANG Yanxin and Khaustov Alexander P.1. china university of geosciences, Wuhan 430074, china 2. Russian {2. of People’s Friendship, Moscow, Russia china university of {2. Wuhan China Russian university of People’s Friendship Moscow Russia

IN recent years,world-wide researches in relation to geologic disposal of nuclear wastes,ore-forming process modelling and ultradeep geologic drilling have been carried out in areas of crys-talline rocks,and,as a resu... 详细信息

关键词： crystalline rocks hydraulic continuity hydrochemistry isotopes.

Exsolution of ilmenite and Cr-Ti magnetite from olivine of garnet-wehrlite

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Science china Earth Sciences 2005年第9期48卷 1368-1376页

作者： LIU Xiangwen1,2. JIN Zhenmin1,3, QU Jing2.& WANG Lu2.1. State Key Laboratory of Geological Processes and Mineral Resources, china university of geosciences, Wuhan 430074, china 2. Graduate School of china university of geosciences, Wuhan 430074, china 3. Faculty of Earth Sciences, china university of geosciences, Wuhan 430074, china State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Wuhan China Graduate School of china university of geosciences Wuhan China Faculty of Earth Sciences China University of Geosciences Wuhan China

Exsolution of rod-like ilmenite (Ilm) and Cr-Ti magnetite (Mt) have been found in olivine of garnet-wehrlite from the core of Chinese Continental Sciences Drilling (CCSD). Their composition, morphology, crystal structure and their topotaxies with host olivine have been studied in detail by the transmission electron microscopy (TEM) and electron probe microanaly- sis (EPMA) technique. It shows that rod-like Ilm exsolution reported in this paper has similar characteristic with that of Alpe Arami olivine, while Cr-Ti magnetite exsolution mentioned in this paper has large discrepancy with chromite exsolution in Alpe Arami olivine. These observations suggest that both of the exsolutions found in this paper should be solid solution phases in β-olivine at their first period, then experiencing decomposition of solid solution and therefore forming Ilm and Cr-Ti magnetite exsolution with the pressure decreasing. So, this garnet-wehrlite perhaps had been ever located in mantle transition zone with a minimum depth of 300 km.

关键词： garnet-wehrlite, ilmenite, magnetite, exsolution, CCSD.

Mechanism for calcite dissolution and its contribution to development of reservoir porosity and permeability in the Kela 2.gas field,Tarim Basin,china

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Science china Earth Sciences 2008年第4期51卷 567-578页

作者： YU BingSong1,3, DONG HailLiang2.3 & RUAN Zhuang1,3 1 State Key Laboratory of Geological Processes and Mineral Resources, china university of geosciences, Beijing 100083. {2. 2.department of geology, Miami university,Oxford, OH 45056, USA 3 Geomicrobiology Laboratory, china university of geosciences, Beijing, 100083. {2. State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing China Geomicrobiology Laboratory China University of Geosciences Beijing China department of geology Miami University Oxford USA

This study is undertaken to understand how calcite precipitation and dissolution contributes to depth-related changes in porosity and permeability of gas-bearing sandstone reservoirs in the Kela 2.gas field of the Tarim Basin, Northwestern china. Sandstone samples and pore water samples are col-lected from well KL2.1 in the Tarim Basin. Vertical profiles of porosity, permeability, pore water chem-istry, and the relative volume abundance of calcite/dolomite are constructed from 3600 to 4000 m below the ground surface within major oil and gas reservoir rocks. Porosity and permeability values are in-versely correlated with the calcite abundance, indicating that calcite dissolution and precipitation may be controlling porosity and permeability of the reservoir rocks. Pore water chemistry exhibits a sys-tematic variation from the Na2.O4 type at the shallow depth (3600-3630 m), to the NaHCO3 type at the intermediate depth (3630―3695 m),and to the CaCl2.type at the greater depth (372.―3938 m). The geochemical factors that control the calcite solubility include pH, temperature, pressure, Ca2. concen-tration, the total inorganic carbon concentration (ΣCO2., and the type of pore water. Thermodynamic phase equilibrium and mass conservation laws are applied to calculate the calcite saturation state as a function of a few key parameters. The model calculation illustrates that the calcite solubility is strongly dependent on the chemical composition of pore water, mainly the concentration difference between the total dissolved inorganic carbon and dissolved calcium concentration (i.e., [ΣCO2. -[Ca2.]). In the Na2.O4 water at the shallow depth, this index is close to 0, pore water is near the calcite solubility. Calcite does not dissolve or precipitate in significant quantities. In the NaHCO3 water at the intermedi-ate depth, this index is greater than 0, and pore water is supersaturated with respect to calcite. Massive calcite precipitation was observed at this depth interval and

关键词： calcite dissolution porosity thermodynamic Tarim Basin

Differential retardation of organic matter maturation by overpressure

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Science china Earth Sciences 2004年第9期47卷 783-793页

作者： HAO Fang1,2. JIANG Jianqun1, ZOU Huayao1, FANG Yong1 & ZENG Zhiping2.1. Key Lab for Hydrocarbon Accumulation Mechanism in the Ministry of Education, Petroleum university, Beijing 102.49, china 2. {2. of Petroleum geology, china university of geosciences, Wuhan 430074, china Key Lab for Hydrocarbon Accumulation Mechanism in the Ministry of Education Petroleum University Beijing China department of Petroleum geology China University of Geosciences Wuhan China

The thermal evolution of organic matter (OM) is composed of a series of reactions that are paralell and successive with each other. Different reactions have different activation energy, different rates of product concentration variation, and different volume expansion effects, and therefore have different responses to overpressure, which determines the differential retardation of different OM maturation reactions and maturity parameters. Based upon comprehensive studies on the OM maturation in different pressure systems in the Yinggehai, Qiongdongnan and Bohai Bay basins, 4 hierarchies of overpressure retardation have been recognized. (1) OM maturation in all aspects has been retarded by overpressure. (2. The thermal evolution of hydrocarbons and thermal degradation of hydrogen-rich kerogens has been retarded, but the thermal evolution of hydrogen-poor kerogen components has not been affected by overpressure. As a result, vitrinite reflectance has not been retarded. (3) The thermal cracking of hydrocarbons has been retarded, yet overpressure has had little or no effect on thermal degradation of kerogens. (4) Overpressure has no detectable effect on all aspects of OM maturation. The hierarchy that overpressure has retarded all aspects of OM maturation is the combined result of early overpressure (overpressure began to develop when the source rock was still immature) and the protracted maintenances of closed fluid system. Any case that overpressure had developed too late, or overpressure was too small to reach the threshold values, or overpressured fluid had been frequently released, could give rise to the occurrence of state 4 that overpressure had no detectable effect on all aspects of OM maturation. It seems that in many basins, overpressure retardation of hierarchies 2.and 3 developed where the most commonly used maturity parameter, vitrinite reflectance, had not been affected. In theses cases, multiple parameters must be used to distinguish overpressure retardati

关键词： overpressure, organic matter maturation, hydrocarbon generation, differential retardation.

Congruences on ideal nil-extension of completely regular semigroups

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Chinese Science Bulletin 1998年第5期43卷 379-381页

作者： REN Xueming 1, 2.GUO Yuqi 2.and CEN Jiaping (Shum Kar-ping) 31. department of Mathematics, Xi’an university of Architecture & Technology, Xi’an 710055, {2. 2. department of Mathematics, Yunnan university, Kunming 650091, {2. 3. department of department of Mathematics Xi’an University of Architecture & Technology Xi’an China department of Mathematics Yunnan University Kunming China department of Mathematics Chinese University of Hong Kong Hong Kong

Let S be an ideal nil-extension of a completely regular semigroup K by a nil semigroup Q with zero. A concept of admissible congruence pairs (δ,ω) of S is introduced, where δ and ω are a congruence on Q and a congruence on K respectively. It is proved that every congruence on S can be uniquely respresented by an admissible congruence pair (δ,ω) of S. Suppose that ρ K denotes the Rees congruence induced by the ideal K of S. Then it is shown that for any congruence σ on S,a mapping Γ:σ|→(σ Q,σ K) is an order-preserving bijection from the set of all congruences on S onto the set of all admissible congruence pairs of S,where σ K is the restriction of σ to K and σ Q=(σ∨ρ K)/ρ K. Moreover,the lattice of congruences of S is also discussed. As a special case,every congruence on completely Archimedean semigroups S is described by an admissible quarterple of S. The following question is asked: Is the lattice of congruences of the completely Archimedean semigroup a semimodular lattice?

关键词： completely regular semigroups ideal nil-extension congruences.

Pattern phenomena in an rf discharge dusty plasma system

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Science china(Physics,Mechanics & Astronomy) 2006年第5期49卷 588-596页

作者： HUANG Feng1,2. YE Maofu2.& WANG Long2.1. College of Science, china Agricultural university, Beijing {2. china 2. Institute of Physics, Chinese Academy of Sciences, Beijing 100080, china College of Science China Agricultural University Beijing China Institute of Physics Chinese Academy of Sciences Beijing China

Various dust patterns are observed in an rf discharge dusty plasma system. According to the dust growth process from small to large in size, the formation of different dust patterns can be divided into two stages: the small-particle stage (or dust cloud stage), and the large-particle stage (or dust crystal stage). The evolution relations between different dust patterns with gas pressure changing are investigated. Dust voids, dust acoustic waves and strong turbulence modes are presented at the small-particle stage. The self-organized dust lattices and dust clusters are investigated at the large-particle stage. The static structure of a dust lattice is characterized by means of the pair correlation function. Dust clusters formed by particles with different numbers and the regular evolution of the clusters with gas pressure are also investigated. The packing sequences of dust clusters are verified through two-dimensional confined molecular dynamics simulations.

关键词： dusty plasma dust patterns

Discovery of seismites in Upper Sinian stratiform lead-zinc deposits in Dadu River valley, Sichuan, china: Implication for ore genesis

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Science china Earth Sciences 2006年第11期49卷 1135-1146页

作者： LIN Fangcheng1,2.& PAN Guitang2.1. Geoscience College, Chengdu university of Technology, Chengdu 610059, china 2. Chengdu Institute of {2. and Mineral Resources, Chengdu 610082. china Geoscience College Chengdu University of Technology Chengdu China Chengdu Institute of geology and Mineral Resources Chengdu China

A number of lead-zinc sulphide deposits have been discovered in recent years in dolo- mitic rocks of the Upper Sinian Dengying Formation in the Dadu River valley region, Sichuan Province, china. The lead-zinc mineralization is closely associated with a black siliceous exhalite that has been traced over 50 km of strike. This makes Dadu River valley the most extensive stratiform non-ferrous sulphide horizon having been discovered to date in china. In a previous study by the first author (LIN), these deposits were recognised as belonging to the broad spectrum of lead-zinc sedimentary exhala- tive (SEDEX) deposits. In this paper, seismites and seismogenetic structures occurring in close association with the Dadu River valley mineralized zone are described. The close spatial and temporal relationship between the seismites and mineralization provides strong evidence for the hypothesis that the lead-zinc SEDEX deposits formed in direct response to earthquake activities around the Sinian-Cambrian boundary. The earthquakes are postulated to be an effective dynamic mechanism for triggering the upward migration of deep circulating ore fluids along synsedimentary growth faults and their exhalation onto the sea-floor to form the extensive deposits of stratiform lead-zinc sulphide ore.

关键词： seismites, earthquake, lead-zinc deposit, hydrothermal exhalation, Upper Sinian Dengying Age.

Experimental remolding on the caprock's 3D strain field of the Indosinian-Yanshanian epoch in Tongling deposit concentrating area

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Science china Earth Sciences 2005年第7期48卷 863-874页

作者： DENG Jun1,HUANG Dinghua2.WANG Qingfei1,WAN Li1,SUN Zhongshi3,YANG Liqiang1 & GAO Bangfei1 1. State Key Laboratory of Geological Processes and Mineral Resources,china university of {2.,Beijing 100083.china 2. Faculty of Earth Sciences,china university of {2.,Wuhan 430074,china 3. department of Earth Sciences,Jilin university,Changchun 130061,china State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China Faculty of Earth Sciences China University of Geosciences Wuhan 430074 China department of Earth Sciences Jilin University Changchun 130061 China

Based on field observations and rheology analysis, we perform one analogue experiment and remold the 3D structural frame of Tongling deposit concentrating area firstly. Then we disassemble and dialyze the 3D structures of the model using the methods of "slicing" and "stripping". A series of sliced planes vertical to the fold hinges show similar landscapes of that in the drill hole profiles. Meanwhile, layer stripping analysis indicates that the deformation features of each layer in the model are qualitatively analogical to those obtained from field observations. Through contrasting the 3D structure between the experimental model and the field phenomena, we verify the following 3D deformation features of the caprock in this area: (1) the Tongling area mainly consists of three series of NE S-typed fold groups; (2. in the uniform stress field, the incoherent folds universally develop in different positions, along different axes as well as in different strata; (3) the faults propagate upward which are mostly inter-bedded detachment faults, while the fold amplitudes decrease while going deeper; and (4) the folds and cleavages are highly developed in the Silurian System indicating that the deformation effect of the Indosin-ian-Yanshanian structural layer terminates at this layer, which suggests that the Silurian System is the crucial layer for the inversion between brittle and plastic deformation domains and the underlying strata are subject to the control of another deformation system with distinct properties.

关键词： Tongling deposit concentrating area Indosinian-Yanshanian epoch 3D structural frame of the caprock analogue experiment slicing and stripping analysis structural model.

Fuzzy controllers based on some fuzzy implication operators and their response functions

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Progress in Natural Science:Materials International 2004年第1期14卷 16-21页

作者： LI Hongxing 1*, YOU Fei 1 and PENG Jiayin 2.1. department of Mathematics, Beijing Normal university, Beijing 100875, {2. 2. department of Mathematics, Neijiang Teacher's College, Neijiang 641112. {2.) Beijing Normal Univ Dept Math Beijing 100875 Peoples R China

The fuzzy controllers constructed by 2. fuzzy implication operators based on CRI algorithm and their response functions are discussed. The conclusions show that the fuzzy controllers constructed by 9 fuzzy implication operators are universal approximators to continuous functions and can be used in practical fuzzy control systems. And these 9 fuzzy implication operators except for Einstein operator intersection are all the adjoint pairs of some fuzzy implication operators. Besides, there are 3 other fuzzy controllers formed by fuzzy implication operators being regarded approximately as fitted functions.

关键词： fuzzy implication operators CRI algorithm fuzzy controllers response functions universal approximators