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961.
Song Xuexin Xu Qingsheng Guo Yuemin Mao Xueying Ouyang Hong Institute of Mineral Deposits Chinese Academy of Geological Sciences Beijing Institute of High Energy Physics Chinese Academy of Sinices Beijing 《《地质学报》英文版》1997,71(3):263-272
REE ratios and patterns for massive pyrite ore and massive cuprous pyrite ore ofthe Baiyinchang orefield are quite similar to those for quartz keratophyritic tuff and quartzalbitophyre of the same orefield. However, massive cuprous pyrite ore of the Ashele Cu-Zn de-posit is similar to basalt-diabase of the same district in REE geochemistry. Comparison of theChinese VMS ores with those from Rio Tinto, Spain and Que River, Australia, in REEgeochemistry has been made. REE ratios and patterns of bedded-massive and massive ores ofthe Changba-Lijiagou Zn-Pb deposit, the second largest SEDEX deposit in China are similarto those of their host rocks, the Qinling shales of Devonian age and the Changba adamellite.The three types of ore and their host rocks of the Dongshengmiao pyrite (pyrrhotite)-Zn-Pbdeposit have parallel REE ratios and patterns. 相似文献
962.
TherelationbetweentheresponsespectrumandthephasediferencespectrumFENG-XINZHAO(赵凤新)andYU-XIANHU(胡聿贤)InstituteofGeophysics,Sta... 相似文献
963.
近二十年来四川地区地震和前兆观测台网得到了较大的发展,获得了丰富的各类连续观测资料,积累了一批宝贵的震例;在中短期地震预报方法和指标的研究,包括观测前兆,地震活动图象,地震波分析,综合预报和现场工作方面取得了多项成果;在9次中强地震前作出了一定程度的中短期预报;同时也存在不足和诸项困难有待解决。 相似文献
964.
ComprehensiveanalysesofseismicsourcelayerinXingtaiandTangshanseismicregionsandtheconditionsofmediaab
ComprehensiveanalysesofseismicsourcelayerinXingtaiandTangshanseismicregionsandtheconditionsofmediaaboveandbelowthisLayerTONG... 相似文献
965.
Liu Human Zhu Min Pan Keqi Yang Liping Tao Xiaxin Zhang Yuming Dong Ruishu Wang Liangmou and Du RuimingInstitute of Engineering Mechanics SSB Harbin China Institute of Geology SSB Beijing China Computer Application Department Harbin University of Architecture Engineering Harbin China 《中国地震研究》1996,(4)
In this paper,the structure of the intelligence-aided seismic zonation system IASHES and its validation are briefly introduced.Emphasis is placed on the two rank scheme of potential seismic source areas; an expert subsystem for estimating the seismicity trends of rank A source areas; an expert subsystem for delineation of rank B source areas; an expert subsystem for judgment of upper limit of magnitude of rank B source areas,and an improved procedure for determination of weighting factors of rank B source areas,which is specially suitable to ES(Expert systems). 相似文献
966.
Yin Xiangchu Chen Xuezhong Song Ziping and Wang YucangCenter for Analysis Prediction SSB Beijing China Institute of Geophysics SSB Beijing China 《中国地震研究》1996,(4)
The temporal variation of LURR(y)for Kanto,Wakayama,and Hugo regions in Japan has been calculated and analysed.The LURR(y)values are significantly higher than 1 before the occurrence of all earthquakes with magnitude M≥6.0 in the Kanto region during the last two decades and the Kobe earthquake(1995-01-17).These results suggest that LURR theory is available for Japan.Recently they-value for Wakayama region has been near 1,while the y-value is remarkably larger than 1 for nearly two years for Kanto.According to these results,it is predicted that a strong earthquake with magnitude of about 6.0 could occur in 1 year or a little longer for in Kanto region or its adjacent regions,but there is little possibility for the Wakayama region. 相似文献
967.
Subsolidus phase relations have been determined in the systems SiO2-Cr-O and MgO-SiO2-Cr-O in equilibrium with metallic Cr, at 1100 to 1500℃ and 0 to 2.88 GPa. The results show that there are no ternary phases in the SiO2-Cr-O system at these conditions, i.e., only the assemblage eskolaite-Cr-metal-quartz (or tridymite) is found. In the MgO-containing system, however, extensive substitution of Cr2+ for Mg is observed in (Mg, Cr2+)2SiO4 olivine, (Mg, Cr2+)2Si2O6 pyroxene, and (Mg, Cr2+)Cr2O4 spinel. Cr3+ levels in olivine and pyroxene are below detection limits. The pyroxene is orthohombic at XCrPx2+ < 0.2, monoclinic at higher XCrPx2+ . Thestructure of the spinels becomes tetragonally distorted at XCr2+Sp >0.2. The experimental datahave been fitted to a thermodynamic model, and the authors obtained the mixing parameter (W) of Mg-Cr2+ in olivine, pyroxene and spinel, and the relation between temperatures and free energies of formation for the end-members: Cr2+-olivine (Cr2SiO4), Cr2+-pyroxene (Cr2Si2O6) 相似文献
968.
969.
Yu Zuxiang Institute of Geology Chinese Academy of Geological Sciences Beijing 《《地质学报》英文版》1996,70(1):27-32
Chengdeite occurs in chromite orebodies in dunite as well as in placers in their neighbourhood. The mineral occurs as granular aggregates in association with inaglyite and in some cases occurs as graphic intergrowths with native iridium. It is opaque with a metallic lustre, colour steel-black, streak black,HM = 5.2, VHN50=452 kg/mm2, cleavage not observed, fracture not observed, strongly magnetic. Its reflection colour is bright white with a yellowish tint. It has no internal reflection, bireflectance or pleochrism, and shows isotropism.Thirteen chemical analyses were carried out by means of the electron microprobe. The mean percentages of the data obtained in the 13 analyses ares S 0.001, Fe 7.9, Ni 0.03, Co 0.03, Cu 0.83, As 0.02, Rh 0.19, Pd 0.00, Os 0.06, Ir 88.5, Ft 2.2 and Pb 0.00. The simplified formula is Ir3Fe, which requires Ir 91.17 and Fe 8.83, the total being 100.00 (% ).Five strongest lines of X-ray powder diffraction (hkl, d, I)are: 111, 2.18 (80);200, 1.89 (60); 220, 1.34 (70);311, 1.142 相似文献
970.
Wang Guanfu Chen Zhihong Ding Shiying Ren FugenTianjin Institute of Geology Mineral Resources Tianjin China 《《地质学报》英文版》1996,70(1):74-86
Based on palaeomagnetic studies of the Precambrian gold deposits in the Xiong'ershan area, Henan Province, the authors infer that the ore-forming processes of the Beiling alteration-type gold ore deposit and the Dianfang breccia-type gold ore deposit started in the Proterozoic, and was superimposed by later mineralization, whereas the mineralization age of the Jiguanshan quartz- vein type gold ore deposit is Yanshanian. 相似文献