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Paleomagnetism of early Triassic Daye Formation and its tectonic implications

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Chinese sci.nce Bulletin 1999年第5期44卷 412-418页

作者： Zhongyue Shen Dajun Fang Penyang Wang Xiaodong Tan Zhaolian Wang Zhejiang Univ Dept Earth Sci Hangzhou 310027 Peoples R China Daqing Petr Inst Daqing 163000 Peoples R China

The new paleomagnetic data of the early Triassic Daye Formation from Hubei Province are reported. The ChRM passes consistency test and reversal test. Two magnetic components were isolated with principal component analysis （PCA）. Component B is a ChRM and component A was acquired by remagnetization during lndosinian cycle. Rock magnetic study shows that the carrier is dominantly detrital magnetite. According to the data, in conjunction with recently published Triassic paleornagnetic results, mean paleopole of the Triassic Yangtze Block is calculated as 30.3°N, 198.4°E, α95 = 9.2°.Distribution of all Triassic declinations indicates obviously local rotation in the mid-Yangtze areas,which results in consistence of the declinations with fold axes. By comparison with Triassic paleomagnetic data in the South China Block and some of geological evidence, it is inferred that the timing of the suture between the Yangtze Block and the South China Block is earlier in western part than in eastern part in the

关键词： Yangtze Block Triassic paleomagnetism collision orogeny.

A CLASS OF r-POINT (r+1)ST-ORDER A-STABLE ONE-BLOCK METHODS WITH DAMPING AT THE INFINITE POINT

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Numerical Mathematics A Journal of Chinese Universities(English Series) 2002年第2期11卷 161-178页

作者： Zhao Shuangsuo(赵双锁) Zhang Guofeng(张国风) dept. of Inform. and Comput. sci. The Second Northwest University for Nationalities Yinchunan 750021 PRC Dept. of Math. Lanzhou University Lanzhou 73000 PRC

This paper presents a class of r-point (r+1)st-order A-stable one-block methods with damping at the infinite point (DIAOB r,r+1 ). Under the conditions of the same order, A-stability, operation count (at each iterative step) and storage space are the same as the methods in , the methods in the paper improve the stability in a neighborhood at the infinite point. And, by using the OOPI method , it possesses much faster rate of convergence for solving systems of nonlinear equations produced by the DIAOB r,r+1 .

关键词： one-block method, stiff problem, A-stability, damping at infinite point.

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冀东晚古生代东湾子岩体的岩石成因研究

岩石学报 2009年第8期25卷 1975-1988页

作者：马旭陈斌牛晓露 Peking Univ MOE Sch Earth & Space Sci Key Lab Orogen Belts & Crustal Evolut Beijing 100871 Peoples R China

冀东晚古生代东湾子岩体由角闪石岩、少量辉石岩和辉长岩组成。典型的堆晶结构、全岩和镁铁质矿物(透辉石、角闪石)的上凸型稀土分布模式、相容元素含量低且变化范围大(如:角闪石岩中V=296×10^(-6)～673×10^(-6))的特征表明了岩体的... 详细信息

冀东晚古生代东湾子岩体由角闪石岩、少量辉石岩和辉长岩组成。典型的堆晶结构、全岩和镁铁质矿物(透辉石、角闪石)的上凸型稀土分布模式、相容元素含量低且变化范围大(如:角闪石岩中V=296×10^(-6)～673×10^(-6))的特征表明了岩体的堆晶成因。计算得到的与辉石岩中的透辉石相平衡的熔体具有很高的稀土含量,轻重稀土分馏较为明显,富集大离子亲石元素(如:Sr,Ba,K),亏损高场强元素(如:Nb,Zr,Ti),具有典型的弧岩浆特征。透辉石和角闪石的矿物成分也具有弧岩浆的特征。高钙透辉石、大量的角闪石与黑云母的存在说明母岩浆富水。透辉石在高P_(H_2O)的状态下与熔体反应,生成角闪石的结构特征也证明了这一点。结合岩体的球化学特征,认为岩浆来源于富集的含有角闪石的尖晶石橄榄岩的部分熔融,母岩浆具有富水的特征(>3%)。考虑到岩体形成时代(～300Ma;Zhao et al.,2007)和地质背景,认为东湾子岩体与位于华北北缘的其它晚石炭-早二叠世的岩体形成于同一构造背景下,都是晚古生代时期古亚洲洋向华北板块之下俯冲的产物。

关键词：冀东晚古生代岩体岩石成因 Late Paleozoic 角闪石岩透辉石结构特征母岩浆 partial melting 高场强元素轻重稀土分馏尖晶石橄榄岩辉石岩 North China depletion 早二叠世元素含量岩浆来源形成时代

Sea water intrusion and salt water intrusion in the coastal area of Laizhou Bay

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Chinese sci.nce Bulletin 1998年第12期43卷 983-992页

作者： Xue Yuqun Wu Jichun Xie Chunhong Zhang Yongxiang Nanjing Univ Dept Earth Sci Nanjing 210093 Peoples R China Nanjing Univ Dept Math Nanjing 210093 Peoples R China

The characteristics, pattern, hydrodynamic and hydrochemical features, and the movement pattern of the salt water-fresh water interface of the sea water intrusion and the salt water intrusion, which occur in the coastal area of Laizhou Bay in Shandong Province, are analysed. The characteristics of the two kinds of intrusion are compared as well. A three-dimensional sea water intrusion model to describe the sea water intrusion with a transitional zone 1.56.0 km wide in the phreatic aquifer and a solute transport model describing the behavior of cations exchange in the process of sea water intrusion are established.

关键词： sea water intrusion salt water intrusion cation exchange salt water-fresh water interface numerical simulation.

Relative dielectric constant from dry rocks

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Chinese sci.nce Bulletin 1999年第24期44卷 2286-2293页

作者： Xiangyun Wang Huadong Guo Chao Wang Peirong Chen Yangshen Shi Chinese Acad sci Inst Remote Sensing Applicat Lab Remote Sensing Informat Sci Beijing 100101 Peoples R China Nanjing Univ Dept Earth Sci Nanjing 210093 Peoples R China

Relative dielectric constant is an important physical factor in the theory of microwave remote sensing and electromagnetic transmission. This note reports the results of detecting relative dielectric constant from 197 rock samples. The regular pattern of the relative dielectric constant varying with microwave spectrum is revealed. The relative dielectric constants, correlated with the type, density, structure and chemical component of the rock, are discussed. The re-

关键词： dry rocks relative dielectric constant microwave remote sensing electromagnetic transmission.

Oxygen isotope geochemistry of phosphorite and dolomite and palaeo-ocean temperature estimation:A case study from the Neoproterozoic Doushantuo Formation, Guizhou Province, South China

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Progress in Natural sci.nce:Materials International 2004年第1期14卷 78-85页

作者： LING Hongfei, JIANG Shaoyong*, FENG Hongzhen, CHEN Yongquan, CHEN Jianhua and YANG Jinghong(State Key Laboratory for Mineral Deposits Research, Department of earth sci.nces, Nanjing University, Nanjing 210093, China) Nanjing Univ Dept Earth Sci State Key Lab Mineral Deposits Res Nanjing 210093 Peoples R China

The Neoproterozoic Doushantuo Formation at Weng’an in Guizhou Province of South China consists of phosphorites and dolomites. Three types of samples are recongnized for the phosphate bearing rocks. In Type I samples, interstitial phosphates occur within the dolomite rocks, whereas in Type III samples, interstitial dolomites occur within the phosphorites; both of them may have diagenetic origin. The Type II samples are interbedded phosphorites and dolomites. Oxygen isotopic compositions of phosphate and coeval carbonate were analyzed. Phosphates of Type I and II samples show similar low δ 18 O phos (SMOW) values of 10.9‰～12.1‰ and 10.7‰～ 12.8‰ , respectively, whereas Type III phosphates show higher δ 18 O phos (SMOW) values of 13.2‰～15.0‰. Dolomites from Type I and II samples have δ 18 O carb (PDB) and δ 13 C carb (PDB) values of -6.2‰～-3.4‰ and -2.2‰～-0.7‰, respectively, whereas interstitial dolomites from Type III samples show lower δ 18 O carb (PDB) and δ 13 C carb (PDB) values of -12.9‰～-8.6‰ and -4.4‰～-2.6‰. Petrology and oxygen isotope data suggest that diagenetic alteration may have partially affected the studied rocks, but the dolomites from Type I and phosphates from Type III samples represent the most pristine isotopic compositions of primary carbonates and phosphates precipitated from seawater. Calculations of palaeocean temperatures from the most 18 O enriched dolomite and phosphate indicate a temperature range of 32.2 ℃ to 34.0 ℃ for the seawater of the Doushantuo Formation period. Ce anomaly also suggests more oxic conditions and possibly shallower water dept. in the upper strata of the Doushantuo Formation at Weng’an, Guizhou Province.

关键词： oxygen isotopes phosphate dolomite Doushantuo Formation Neoproterozoic South China

CALCULATION OF α3 COEFFICIENT OF SCALAR FIELD BY POINT SEPARATION METHOD

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Acta Mathematica sci.ntia 1988年第2期 211-226页

作者：许殿彦 Center of Theoretical Physics CCAST (World Laboratory) Beijing dept. of Comp. sci. & Tech. Peking University

The α3 coefficient of scalar field in arbitrary Riemann space-time background is calculated by point separation method in this article. The primary expression of α3 involves 25 invariants. Using the identities derived in the appendix, we can reduce α3 from 25 invariants to 17 invariants which agree with Gilkey’s formula for αs coefficient of the scalar field derived by geometric methods and reasons. Recently we derived two important invariant identilies, using these identities we can reduce α3 from 17 invariants to 15 invariants which would much simplify the calculation of the energymomentum tensor of vacuum polarization.

关键词： Ra RR ZR CALCULATION OF COEFFICIENT OF SCALAR FIELD BY POINT SEPARATION METHOD 一命

Hybridization between microstructure and magnetization improvement in lead and RE co-doped BiFeO_3

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Journal of Rare earths 2016年第5期34卷 495-506页

作者： M.A.Ahmed S.F.Mansour S.I.El-Dek M.M.Karamany Materials sci.nce Lab.(1) Physics Dept.Faculty of ScienceCairo University Physics Department Faculty of ScienceZagazig University Materials sci.nce and Nanotechnology dept. Faculty of Post Graduate Studies for Advanced SciencesBeni-Suef University Basic sci.nce dept. Faculty of EngineeringBritish University in Egypt

The crystal structure,magnetic and electrical properties of Bi（0.96）Pb（0.04） FeO3 and Bi（0.92）Pb（0.04）RE（0.04）FeO3（RE=La,Sm,Dy and Yb）polycrystalline samples were prepared by the flash autocombustion technique.X-ray diffraction（XRD）measurements show that the rare-earth doped compositions crystallized in rhombohedral symmetry of space group R3 *** undoped sample consisted needle shape particles while rare earth substitution preferred platelet like particles as clarified from high resolution transmission electron microscopy（HRTEM）.Morphological features were examined using field emission scanning electron microscopy（FESEM）.Magnetization measurements showed that Yb^3＋ samples possessed the highest room temperature saturation magnetization while when Bi^3＋ ions were substituted by La^3＋ ions,a smaller MS（0.28 emu/g）was *** coexistence of ferroelectric and magnetic transitions was detected using DSC and χM,indicating the multiferroic characteristics of Bi（0.92）Pb（0.04）RE（0.04）FeO3 *** Néel temperature shifted upwards with decreasing the ionic radius of rare earth *** correlation was established between microstructure,morphology and magnetic properties in view of the contribution of magnetocrystalline and shape anisotropy in the magnetic parameters values.

关键词： BiFeO3 multiferroic rare earths anisotropy dielectric conductivity Neel temperature

High-resolution dipole ( e, e ) study for optical osci.lator strengths of valence shell excitation of nitrogen

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Chinese sci.nce Bulletin 1997年第17期42卷 1426-1429页

作者： Zhang, XJ Feng, RF Zhong, ZP Ji, Q Zhu, LF Wu, SL Xu, KZ Department of Modern Physics Univ. of Sci. and Technol. of China Hefei 230027 China

NITROGEN is the most abundant element in the earth’s atmosphere. The study of optical osci.lator strengths of nitrogen is of great significance in atmosphere physics, space physics and environment sci.nce. These results are also used in many fields, such as fusion plasma and developments of the nitrogen laser. As we know, calculation of absolute optical osci.lator strengths of molecular nitrogen are still at the level of electronic rather than vibronic states resolved.

关键词： nitrogen optical osci.lator strength high-resolution dipole (e e) method electron energy-loss spectrum.