Abnormal animal behaviour as a precursor of the 7 December 1988 Spitak,Armenia, earthquake

This paper relates some facts about abnormal animal behaviour prior to several Armenian earthquakes. The catastrophic Spitak, northern Armenia, earthquake of 7 December 1988, M = 7, I ₀ = X, was preceded by extensive occurrences of abnormal animal behaviour. Proof was established by questioning residents in the area and by distributing specially prepared questionnaires shortly after the event. Approximately 200 reports from 50 sites were examined. The raw data recorded included lists of different types and locations of species that have shown abnormal responses to an impending earthquake, distribution of anomalous occurrences over the area, and precursor times. It is concluded that specially conducted observations of animal behaviour as a possible premonitory phenomenon is both useful and necessary.     

福建水氡对闽台地震的映震分析

利用福建水氡台网 1 990年以来的水氡资料 ,针对 6次福建及其东南沿海大于 4 5级地震 ,7次台湾及其近海大于 6 8级地震进行分析研究 ,认为地震前异常存在加速性、同步性 ,形态的多样性 ,空间分布的不确定性。运用“九五”攻关软件 ,给出上述两区域地震异常特征的共性和个性 ,并对映震效能进行R值评分     

乌鸦咀泉的外界干扰分析

本文对近期乌鸦咀泉异常进行宏观和微观分析 ,通过对此次异常和以往异常进行对比分析 ,以及对不同位置水样进行对比观测 ,指出该异常由下水道污水引起 ,且此次污染源同以往不同 ,进而对今后的工作提出几个建设性意见。     

白狐沟井水位与地震

白狐沟井位于包头市北部，从１９７９年对该井水位曾续观测。１９７９年８月２５日包头西五原县发生Ｍｓ６．０级地震，１９８１年９月３１日包头东丰镇发生Ｍｓ５．８级地震。在观测中，震前该井水位均发生了明显异常，为地震预报提供了较可靠的依据。     

煤矿塌方地震资料的初步分析

本文对矿区塌方地质构造的分析表明,矿井塌方地震与矿区的局部地质构造有密切的关系。通过对山东陶压煤矿塌方地震资料的初步分析表明,在较大的塌方地震发生之前,有以下异常出现:小塌方地震次数增多,∑N——t曲线、∑E~(1/2)—t曲线、∑L—t曲线及N_o—∑△t曲线急剧变化。这些异常变化一般出现在较大塌方地震前12——70天。依此有可能对较大塌方地震做出预报。     

An analysis of the seasonal variation of disturbance in georesistivity

Four types of disturbances in the seasonal variation in georesistivity are presented in the light of specific circumstances in China. As the results of theoretic calculation for the models and in comparison of the calculated results with the seasonal variations observed at 40 georesistivity stations, the following points are found: (1) The seasonal variation in georesistivity is caused by the change in resistivity of the surface layer, especially by the annual variation of phreatic level when the sounding depth is too shallow. This is one of the disturbances and thus has no relation to the origin of earthquake. The feature and amplitude of the seasonal variation depend on the types of disturbance models, geoelectric cross sections and sounding depth. (2) The seasonal variation in georesistivity usually has the same sign as that of the change in resistivity of shallow layer and thus the normal seasonal change appears. However, as far as the K or Q types of geoelectric cross sections are concerned, the abnormal seasonal variation in georesistivity starts to appear with a certain electrode spacing, when the interference layer is located in the first layer. (3) Both abnormal and normal seasonal variations in georesistivity will be smaller than 2% when the sounding depth is greater than 300 m. Therefore, the seasonal variations can be removed or restrained when the location of observation has been properly chosen or the electrode spacing is enlarged enough to obtain a sufficient sounding depth.     

新疆北天山推覆带大地电磁测深应用研究

利用远参考与Robust技术手段对新疆北天山地区大地电磁原始资料进行去噪处理,以及静态校正、逐级反演、梯度法、残差法等处理与综合地质解释,取得了较好成效。将该区划分为四棵树凹陷、山前断褶带、北天山推覆带、中天山隆起带四大构造单元,其中北天山推覆带地表裸露石炭系基岩。在推覆断层之下,显示中浅部存在层状低阻异常带,推测为侏罗与白垩系地层,为油气远景区。     

Grain growth in the forsterite-diopside system

Grain growth experiments in dunite, clinopyroxenite, and wehrlites with various forsterite/diopside ratios were performed to investigate the effect of modal composition on grain growth kinetics in the Earth's uppermost mantle. The experiments were conducted using a piston-cylinder apparatus at 1200 °C and 1.2 GPa for 2-763 h under dry conditions. Normal grain growth (NGG) occurred in dunite, clinopyroxenite, and relatively forsterite-poor wehrlites (≤70 vol.% of forsterite). Grain growth rates of forsterite and diopside in relatively forsterite-poor wehrlites were much slower than those in dunite and clinopyroxenite. In the forsterite-rich wehrlites (≥80 vol.% of forsterite), NGG of diopside and abnormal grain growth (AGG) of forsterite occurred. The growth rate of diopside was significantly slower than that in clinopyroxenite, while the growth rate of forsterite by AGG was found to be similar to that by NGG in dunite. The presence of ≤20 vol.% diopside had the effect of inhibiting the forsterite grain growth during the initial stage, resulting in AGG of forsterite, thus overtaking the growth rate in dunite. Our experimental results suggest that there would be a significant difference in grain growth rate and consequently in effective viscosity between olivine-rich peridotites (depleted mantle) and relatively olivine-poor peridotites (fertile mantle) in the case of grain size-sensitive creep. Variation of mean grain sizes in the upper mantle would result not only from differences in temperature and phase assemblage, but also from the variation of modal compositions.     

广东鼎湖钼矿区的生物地球化学效应

本文论述了广东鼎湖钼矿区生物地球化学异常特征和植物波谱特征，并对该区的ＴＭ图像进行了较深入的分析与应用处理。研究结果表明，钼矿区的植物波谱反射率与ＴＭ灰度值均比对照区的高，经Ｋ－Ｌ变换后的ＴＭ假彩色合成影像上，钼矿区呈现的形状、色调均与对照区有明显区别，研究区ＴＭ影像特征主要受植物叶中的铝含量及叶绿素含量的影响。本研究结果为在植被覆盖区用生物地球化学遥感探矿提供了理论依据。     

Anomalies in Water Level Records in Yunnan Caused by the Great Indonesian Earthquakes and Their Significance

Two great earthquakes occurred in the sea northwest of Sumatra, Indonesia, on December 26, 2004 and March 29,2005. The observation of water levels in Yunnan yielded abundant information about the two earthquakes. This paper presents the water level response to the two earthquakes in Yunnan and makes a preliminary analysis. It is observed that the large earthquake- induced abnormal water level change could be better recorded by analog recording than by digital recording. The large earthquake-caused water level rise or decline may be attributed to the effect of seismic waves that change the stress in tectonic units, and is correlated with the geological structure where the well is located. The water level response mode in a well is totally the same for earthquakes occurring on the same fault and with the same fracture mode. The only difference is that the response amplitude increases with the growth of the earthquake magnitude.