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941.
非线性参数H值用于华北地区的预报方案研究及检验 总被引:2,自引:0,他引:2
陈佩燕 《地震地磁观测与研究》1996,17(1):76-80
本文研究了非线性参数H值曲线与华北强震之间的关系。将RSH算法应用于华北地区,研究了定量预报指标的方案,并进行了回溯性预报检验。 相似文献
942.
943.
944.
Mi?raç Akçay H.Mustafa Özkan Charles J. Moon Barry C. Scott 《Journal of Geochemical Exploration》1996,56(3):197-218
Orientation studies over the Sarpda? prospect in the Biga peninsula and the Arapdagi deposit near Izmir have provided elear evidence for elemental dispersion around west Turkish gold prospects. Although these deposits are of different types, silicification associated with the deposits results in the main part of both deposits forming topographic highs.At Sarpda? gold mineralisation is relatively weak compared with nearby prospects and associated with a silicified cap on the main hill. Comparison of coarse and fine fractions, based on a 190 μm size split of 8 kg of -2 mm material, suggests that gold disperses clastically on the steep slopes, probably within silica, but coarse grains break down giving Au concentrations in the finer fractions at the base of the main slope. Discrete gold grains, that can be panned, only occur 1–2 km downstream within the streams and heavy mineral concentrations are very limited. This interpretation of Au dispersion is consistent with the data from 1 kg samples collected at the higher primary grade, but more contaminated, Arapda?i prospect.Antimony is the most consistent pathfinder both for the silicified cap at Sarpda? and for gold-rich veins at Arpada?i. It gives high contrast anomalies. Arsenic is useful being more mobile than Sb, although contrast may be low. High resolution Ag data can be useful but base metal enrichments are also often associated with Ag anomalies. Most prospects have some base metal enrichments although they can be displaced from the main gold-rich parts of the deposit and anomalies may be weak. Lead and Cu are the more consistently useful elements.The use of large (> 8 kg of -2 mm material) samples produces consistent stream sediment data that can be used to reliably interpret single samples and quantify Au anomalies. A survey around the Halíköy Hg and Emirli Sb mines, using these large samples, confirmed the extension of the known gold-bearing Emirli structure. In contrast the major Hg-bearing Halíköy Fault is gold poor although a structure parallel to it is auriferous. 相似文献
945.
Recently discovered dinosaur bones in submerged near-shore deposits of southwest Istria include one vertebra, one femur, and two rib fragments. They all show well-developed vascularization. The large amounts of primary bone tissue in the vertebral and femoral compacta as well as in one rib fragment suggest that they belong to sub-adult animals which were growing rapidly. The structure of a second rib fragment differs in that it consists of secondary bone. The absence of lines of arrested growth is evident in all investigated bones. This suggests a sustained manner of bone deposition. 相似文献
946.
A complete spectrum of Lyapunov exponents (LEs) is obtained from 1970— 1985 daily mean pressuremeasurements at Shanghai by means of a correlation matrix analysis technique and it is found that there exist LEs≥0,and <0. with their sum 0λ_i=K=0.110405 whereuponT=1 /K =9 is obtained as the predictable time scale, a result close to that acquired by the dynamic-statistical approachin early days and also in agreement with that present by the authors themselves(1991). 相似文献
947.
在山西断陷带西侧吕梁隆起的西坡上,有人认为有一条纵贯全区的离石断裂带,并把其作为鄂尔多斯断块和太行山断块的分界断裂,本文通过近期的工作结果及对深部构造、岩浆活动和钻孔资料的分析,认为把离石断裂带作为构造单元的分界断裂的依据不足。 相似文献
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949.
In this paper, based on the previous study of practical use of seismic regime windows and seismic regime belts, the problem
of establishing a “seismic regime network” consisting of “windows” and “belts” is further posed and discussed according to
the observed fact that many “windows” and “belts” make responses to one earthquake. For the convenience of usage, the “seismic
regime network” is divided into two classes, the first class and the second one. The former can be used in tendency prediction
for long-term seismic activity in a large area, the latter used in short-term prediction in a small area. In this paper, after
briefly discussing the physical significance of “seismic regime network”, it is pointed out that this simple and easily used
method can be used to observe and extract seismic precursory information from a large area before a great earthquake, thus
it can provide a reliable basis for the analysis and judgement of seismic regime tendency in time and space. No doult, this
method is of certain practical significance.
The Chinese version of this paper appeared in the Chinese edition ofActa Seismologica Sinica,13, 161–169, 1991.
The English version of this paper is improved by Prof. Shaoxie Xu. 相似文献
950.
计算伸展断层底界面深度的作图法简介 总被引:2,自引:0,他引:2
本文简介了计算正断层底界滑脱面深度的3种几何作图法。其中,M.W.Kilsdonk(1989)在Davison(1985)方法基础上作出的修正方法,简便且较准确。运用这种方法计算的鲁西地区深层次滑脱面深度与壳内低速层深度吻合。 相似文献