云南地区强震活跃期前调制比的中长期近场特征

通过逐年追踪云南地区 3～ 4 5级地震调制比图象 ,在以 0 67≤Rm <1为异常指标基础上研究了调制地震的中长期近场特征 ,发现 :强震活跃期前调制比的异常区预示了活跃期强震的危险区 ;调制比最大值出现在活跃期前 3～ 5年 ,活跃期前 1～ 2年整个云南地区无调制比异常 ;强震连发背景下的后续强震仅在震前 1年异常 ;7级地震间发生的 6 7～ 6 8级地震调制比异常幅度小。     

Zinc-rich Pyrite from the TAG Active Mound, the TAG Hydrotherma Field, Mid-Atlantic Ridge

Abstract: Pyrite rich in Zn, up to 3.1 wt%, was found in the TAG active mound of the TAG hydrothermal field, the slow-spreading Mid-Atlantic Ridge at 26°08'N and 44°49'W. The Zn-rich pyrite is characterized by an optical homogeneity, a homogeneous distribution of Zn in the back-scattered electron images, both at a magnification of about 500, a negative correlation between Fe and Zn contents of the pyrite and a rather small unit cell edge (a₀ = 5.4117 ± 0.0008Å), strongly indicating that the detected Zn is present in the pyrite in solid solution. Such Zn concentrations are observed exclusively in dendritic pyrite, suggesting that the Znrich pyrite grew from hydrothermal fluids of a high degree of supersaturation due to quenching on the seafloor.     

Robust估计的算法优化

本文分析了Ｒｏｂｕｓｔ估计收敛慢的原因，提出以最小二乘平差的残差（Ｖ）为初始信息，用Ｌ１估计的权函数所计算的权力初始权，根据迭代计算的残差的大小，及残差的变化所提供的信息，构造出加速收敛的算法，计算结果表明，较之一般的方法，迭代次数显著减少，辨识杠杆点含粗差的能力有较大提高，即搜索粗差的效率有很大提高。     

A Review of Catalogues of Chinese Earthquakes

In the past decade, the most authoritative catalogues of Chinese earthquakes and the most popular with seismologists in China are the following:(1) Gu Gongxu, 1983, Catalogue of Chinese Earthquakes;(2) Min Ziqun, 1988, Concise Catalogue of Chinese Earthquakes;(3) Xie Yusuou, 1989, Catalogue of Chinese Earthquakes (M≥ 4.7) from 1900-1980 with Uniform Magnitudes; and(4) Min Ziqun, 1995, Catalogue of Chinese Historical Strong Earthquakes. Earthquakes that occurred before 1900 are mainly documented in historical records.Since 1950s, more recent earthquakes were documented in two major compilations of historical records finished in 1956 and 1983-1987. Separately this effort resulted in two chronicles: two volumes for the first one and five volumes for the second one. The magnitudes are converted from the maximum intensity. These magnitudes, by convention, are connected with surface wave magnitudes. However, it is clear that they do not have any strict seismological definition.The period of 1900-1962 documen     

北京地区夏季背景气溶胶的特征

本文通过对观测资料的统计分析和比较研究,初步揭示了北京地区夏季背景气溶胶的一些特征,其中包括元素浓度及其变化、富集因子和气溶胶来源等。     

汾渭地震带的地震活动性

根据历史强震与现代地震的资料,研究、分析了汾渭地震带强震及中、小地震的时、空、强分布特征,对该带未来地震危险性进行了探讨。     

A data collection and analysis system for research on rock fracturing

We have made a data collection and analysis system for recording microcracks in rock to study the three dimensional pattern of fracture and the dynamic properties of rock during pressurization. This system, with 8 channel data detection, records in real-time, from the initial microcracks to the final vibration waveform excited by the master fracture. The detected data are recorded digitally at the hard disk of an IBM computer (or 286, 386 personal computer) as well as transmitted to disk. The sampling rate for each channel is 10 MHz. Collecting every acoustic emission events in the loaded rock sample with 8 channels by this system, mathematically modelling the AE event travel time, and taking the coordinates of the AE event hypocenter and the three components of P wave velocity as unknown parameters, we set up a set of residual equations for joint inversion, so that the three dimensional localization of AE event hypocenters can be completed under variable velocities, which will lay foundations for the research on rock fracture clearly. The Chinese version of this paper appeared in the Chinese edition ofActa Seismological Sinica,13, 489–495, 1991. The design and development of the system, and the experiments are sponsored by the Chinese Joint Seismological Science Foundation.     

关于金伯利岩分类命名的建议

国内岩石工作者对金伯利岩的分类命名不尽统一,阻碍了各金伯利岩产区的相互交流和对比。本文在分析国内现有多个分类方案的基础上,汲取其合理部分,并结合代表性产地的实际资料,提出关于对我国内生金伯利岩按“构造-结构-矿物(金云母)含量”定量分类命名的表格。     

Characteristics of the Two Types of Granits at Sikongshan in the Eastern Part of the Dabieshan Mountains

It has been shown from petrologic,geochemical,trace element and REE evidence that the gran-ite intrusions at Sikongshan,Anhui Province,can be assigned to two distinct types which are radically different in age and origin.The Precambrian gneissic granited resulted from remelting of old continental crust while the Mesozoic granites were derived ,also through remelting,from low-Rb/Sr rocks at greater depths.Granite masses at Tiantangzhai and Zhoujiawan in the Dabieshan Mountains are also dicussed.