Zircon U–Pb age, trace element and Hf isotope composition of Kongling terrane in the Yangtze Craton: refining the timing of Palaeoproterozoic high-grade metamorphism

U–Pb age, trace element and Hf isotope compositions of zircon were analysed for a metasedimentary rock and two amphibolites from the Kongling terrane in the northern part of the Yangtze Craton. The zircon shows distinct morphological and chemical characteristics. Most zircon in an amphibolite shows oscillatory zoning, high Th/U and ¹⁷⁶Lu/¹⁷⁷Hf ratios, high formation temperature, high trace element contents, clear negative Eu anomaly, as well as HREE-enriched patterns, suggesting that it is igneous. The zircon yields a weighted mean ²⁰⁷Pb/²⁰⁶Pb age of 2857 ± 8 Ma, representing the age of the magmatic protolith. The zircon in the other two samples is metamorphic. It has low Th/U ratios, low trace element concentrations, variable HREE contents (33.8 ≥ Lu_N≥2213; 14.7 ≤ Lu_N/Sm_N ≤ 354) and ¹⁷⁶Lu/¹⁷⁷Hf ratios (0.000030–0.001168). The data indicate that the zircon formed in the presence of garnet and under upper amphibolite facies conditions. The metamorphic zircon yields a weighted mean ²⁰⁷Pb/²⁰⁶Pb age of 2010 ± 13 Ma. These results combined with previously obtained Palaeoproterozoic metamorphic ages suggest a c. 2.0 Ga Palaeoproterozoic collisional event in the Yangtze Craton, which may result from the assembly of the supercontinent Columbia. The zircon in two samples yields weighted mean two-stage Hf model ( T _DM2) ages of 3217 ± 110 and 2943 ± 50 Ma, respectively, indicating that their protoliths were mainly derived from Archean crust.     

关于国有地了企业经营者实行年薪制的构想

为建立社会主义市场经济的地矿工作新秩序，本文对国有地矿企业的经营者（厂长、经理）这一特殊群体进行了分析。着重研究了新形势下企业经营者实行年薪制的问题。指出年薪制就是以企业一个生产经营周期为单位确定经营者的报酬，这一周期通常为一年。进而阐述了为什么要实行企业经营者年薪制；企业经营者的收入应与职工工资完全脱钩；采用基础报酬加效益报酬的方法确定收入等等。并构想了实行经营者年薪制所需要的外部环境：建立经营者人才市场、经营者要能进能出、实行任职资格制度、建立风险机制、按劳动力市场经济规律办事。     

DCMT光电扫描主测微器的设计与研究

DCMT主测微器不同于其它类型的子午环测微器,它具有自校准测定仪器参数的功能。该测微器采用了活动光栅的方案,其优点是能观测近极星和各类准直像;活动光栅另一个显著优点是不同赤纬星几乎可用相同的观测时间.对“V”形光栅的工作原理和误差进行了详细讨论,并给出了一组严格的公式。其系统误差来源有:光栅形状改正、光栅驱动方向相对于光栅的倾斜、光栅驱动方向相对于赤径方向的倾斜、星径曲率改正。     

1966年邢台7.2级地震的构造背景和发震构造

本文根据石油地质勘探的最新资料和元-济人工地震地壳测深剖面相应地段重新解释的结果,分析了邢台7.2级地震的构造背景和发震断裂。研究结果表明,7.2级地震震中位于束鹿断陷盆地南部次凹的东缘,该次凹发育在由新河断裂等4条缓倾铲形正断裂分制围限地台盖层而成的“斛”状构造块体上,块体之下的地壳中存在两条倾向相反的高角度断裂;地震与断陷主断裂及其控制的断陷盆地并非是简单的对应关系,7.2级地震的发震断裂不是单一的缓倾铲形新河断裂或其下方的高角度的F_3断裂和深部的东断裂,而是它们的组合,且高角度断裂是发震断裂的主要部分     

The distribution of QSO absorption lines and its implications

The distribution of L absorption lines has been investigated in the fractal scheme. It is found that (1) the L absorption clouds distribute completely different from that of galaxies; (2) the L absorption clouds are anti-associated with galaxies and quasars. These results may imply that there are two kinds of objects formed by different processes of clustering. This is favourable for the cosmic-string theory on the formation of large-scale structure of the Universe. In the string model, the objects can be divided into two kinds according to their clustering with or without string loops as their initial density perturbation.On leave from the Center of Astrophysics, University of Science and Technology of China, Hefei, P.R. China. Y. Chu is a research fellow of Alexander von Humboldt-Foundation.     

树木年轮重建阿勒泰西部1481-2004年6-9月降水量序列

根据采自阿勒泰西部地区5个采点的树木年轮样本, 建立了该地区的树轮年表. 通过相关普查发现, 其差值年表序列与该地区当年6-9月的降水量存在明显的负相关关系, 且具有明确的树木生理学意义. 用沙勒哈(t, t 1)两个树轮差值年表序列可较好地重建该地区1481-2004年524 a来的当年6-9月的降水量, 且经过交叉检验表明重建方程稳定可靠. 分析发现, 阿勒泰西部地区524 a来的重建降水量序列具有9个偏干阶段和9个偏湿阶段, 并且具有34.8 a、 5.0～5.1 a、 4.3～4.4 a、 3.9～4.0 a、 3.7 a和3.4 a的显著干湿变化准周期. 重建降水量序列在1518年、 1548年、 1634年、 1765年、 1856年前后发生过突变.     

分光光度法测定海洋河弧菌510脂多糖

本文研究了直接测定海洋河弧菌 (vibrio fluvailis) 5 10脂多糖的分光光度法。利用 1,9-二甲基亚甲蓝 (DMB) ,在适当条件下同脂多糖发生染色反应 ,在 5 5 0 nm波长下 ,反应体系的吸光值同脂多糖含量呈线性相关。相关系数为 0 .9993,最低检出限为 10 μg/m L,相对标准偏差为 1.6 2 ,平均回收率为 (10 5± 2 .18) %。     

A combined numerical tidal model for the Hangzhou Bay and Qiantang River

-In order to avoid prescribing open boundary condition on the upstream side of the Hangzhou Bay, in numerical simulation of the tides and residual currents of the Bay, a 1-D model for the Qiantang River is connected to the 2-D model for the Hangzhou Bay. The harmonic constants of diurnal constituent [ (K1 O1)/2],semidiurnal constituent (M2) and shallow water constituent (M4) are obtained. The results produced by the combined model are in better agreement with the observed ones than those produced solely by the original 2-D model. The combined model gives much more reliable results for tide-induced residual water level and current.     

CHARACTERISTICS OF TIDAL FLATS OF THE ZHUJIANG RIVER MOUTH

The intertidal zone of the Zhujiang River mouth tidal flat is about 570,000 mu in total, and the tidal flat of the subtidal zone (shallower than -2 m of the Huanghai Sea base level) is 560,000 mu. The two types, silty mud and argillaceous silt, are predominant in the tidal flat area, which can be divided into five types in terms of origin: 1) river mouth sand spit-subaqueous natural levee type; 2) river mouth bar type; 3) bay head type; 4) around the island type; and 5) marginal flat type. The tidal flat of the Zhujiang River mouth belongs to the depositional type and is constantly accumulating silt while extending, with an average land formation of 8,940 mu/yr in 97 years (1883-1980).