豫西东秦岭造山带核部杂岩中钙质变质岩的变质作用演化   总被引：3，自引：0，他引：3  

陈能松  张兴辽 《岩石学报》1993,9(3):240-254

  相似文献   

热液中硫化物与硫代硫酸盐的同位素交换机制及多硫化物的作用     

储雪蕾 《岩石学报》1993,9(3):255-266

  相似文献   

海洋构造地球物理当前动态、前景及我们的发展方向     

夏戡原 《地球科学进展》1992,7(2):1-4

    海洋构造地球物理或构造物理学是海洋地球科学研究的前沿。它是构造地质学和地球物理学互相渗透、互相促进的一门很有前景的新兴边缘学科。80年代这一新兴学科有较明显的发展，90年代这一学科在板块运动、驱动机制的定量研究以及在巨型断裂、造山带与盆地形成机理等方面的研究将有重要的突破，我国在90年代应加强对南海这一西太平洋最大的边缘海的构造地球物理研究。  相似文献   

雷州半岛局部地热异常及其形成机制   总被引：15，自引：0，他引：15       下载免费PDF全文

陈墨香  夏斯高 《地质科学》1991,(4):369-383

雷州半岛地热场主要受基底构造格局的控制和地下水活动的影响,隐伏花岗岩体放射性元素生热对盖层地温的贡献不可忽视,第四纪更新世火山喷发活动的岩浆余热已几乎完全散失,岩浆体和围岩温度已趋于平衡。由火山喷发而形成的雷北螺岗岭和雷南石峁岭两个玄武岩台地,为半岛地下水的主要补给区,由于冷水流下渗的地温效应,新生界盖层浅部地温梯度<3℃/100m,呈现地热负异常。在以传导传热为主的区域,地热场特点与华北盆地相似,新生界盖层地温梯度与基底岩面的埋深密切相关。由于地壳深部较均一的热流在地壳表部再分配的结果,若干凸起区盖层地温梯度为4—5℃/100m,呈现地热正异常。某些控制凸起区的边界断裂,当深层热水沿其上涌,造成附加热源,和传导传热相叠加,盖层地温梯度可高达5—8℃/100m,形成更鲜明的地热正异常。  相似文献   

新疆黄山杂岩体矿物学特征及其意义   总被引：1，自引：0，他引：1  

钟应先 《矿物岩石》1991,11(1):14-23

黄山杂岩体造岩矿物有橄榄石、斜方辉石、单斜辉石、斜长石、角闪石和黑云母。其中斜方辉石的多色性不是由Fe~(2+)引起,而是由Ti~(4+)引起。单斜辉石结晶后常与岩浆继续发生化学反应,形成一种岩浆岩结构——角闪反应补丁结构。橄榄石中镍含量的亏损程度反映杂岩体曾经历过硫化物熔离作用。单斜辉石Si,Al~Ⅳ,Ti的变化表明杂岩体属于拉斑玄武岩系列。超镁铁岩中K,Ba,Th,Hf等元素反常的地球化学行为是由该岩石中黑云母矿物引起。  相似文献   

Deep-crustal earthquakes in the southern Baltic Shield   总被引：1，自引：0，他引：1  

Ronald Arvidsson  Rutger Wahlström  Ota Kulhánek 《Geophysical Journal International》1992,108(3):767-777

  相似文献   

山西地区的震源机制解结果     

刘巍  赵新平  安卫平  张开建 《山西地震》1993,(2)

选用山西地区丰富的地震资料,利用单台小震综合断面解、4级以上地震的P波初动解、多台小震综合断面解的结果,叙述了山西地区震源机制结果的特点.得出山西地区震源机制结果有一定的复杂性,小震综合断面解的结果与华北地区的震源机制结果相似,单个地震的震源机制结果一致性较差的结论.  相似文献   

日本地震电磁辐射研究的进展与动向   总被引：3，自引：0，他引：3  

钱书清 《国际地震动态》1993,(6):6-9

  相似文献   

A NUMERICAL STUDY FOR MECHANISM OF THE EFFECT OF NORTHERN SUMMER ARCTIC ICE COVER ON THE GLOBAL SHORTRANGE CLIMATE CHANGE          下载免费PDF全文

Ni Yunqi  Zhang Qin  Li Yuedong 《Acta Meteorologica Sinica》1992,6(1):15-24

In terms of nine-layer global spectral model involving fuller parameterization of physical process,with arhomboidal truncation at wavenumber 15,experiments are conducted by virtue of two numerical schemes,one withlong-range mean coverage of Arctic ice,and the other with supercooled water at the same temperature as the ice,fol-lowed by an analysis of the difference field simulated by the two schemes.Results show that(1)the impact of Arctic iceon the northern short-range climate is realized through the change in polar ice coverage to cause local temperaturechange in the polar region to set up gradient difference in temperature from north to south,thus affecting the atmospher-ic circulations and,on the other hand,two trains of two-dimensional Rossby waves excited by the atmospheric heatsource anomaly have impacts on the Northern Hemisphere(NH)extratropical region,one of which is similar to the JPteleconnection pattern first presented by Nitta(1987);(2)The significant impact of Arctic ice anomaly on the southernshort-range climate change is accomplished with the aid of the anomaly of the equatorial heat source that excites a two-dimensional Rossby wavetrain propagating along a great circle route into the Southern Hemisphere(SH)extratropics,and the cross-equatorial propagation of the NH wavetrain also has effects on the SH atmosphere.Simulation indicatesthat with the 15-day integration the Arctic ice exerts an influence mainly on the NH and when the model atmosphere isgetting stabilized,the effect is dominantly on the SH short-range climate change.  相似文献   

Numerical study of the oxidation process of dimethylsulfide in the marine atmosphere   总被引：1，自引：0，他引：1  

Seizi Koga  Hiroshi Tanaka 《Journal of Atmospheric Chemistry》1993,17(3):201-228

A box model, involving simple heterogeneous reaction processes associated with the production of non-sea-salt sulfate (nss-SO ₄ ^2– ) particles, is used to investigate the oxidation processes of dimethylsulfide (DMS or CH₃SCH₃) in the marine atmosphere. The model is applied to chemical reactions in the atmospheric surface mixing layer, at intervals of 15 degrees latitude between 60° N and 60° S. Given that the addition reaction of the hydroxyl radical (OH) to the sulfur atom in the DMS molecule is faster at lower temperature than at higher temperature and that it is the predominant pathway for the production of methanesulfonic acid (MSA or CH₃SO₃H), the results can well explain both the increasing tendency of the molar ratio of MSA to nss-SO ₄ ^2– toward higher latitudes and the uniform distribution with latitude of sulfur dioxide (SO₂). The predicted production rate of MSA increases with increasing latitude due to the elevated rate constant of the addition reaction at lower temperature. Since latitudinal distributions of OH concentration and DMS reaction rate with OH are opposite, a uniform production rate of SO₂ is realized over the globe. The primary sink of DMS in unpolluted air is caused by the reaction with OH. Reaction of DMS with the nitrate radical (NO₃) also reduces DMS concentration but it is less important compared with that of OH. Concentrations of SO₂, MSA, and nss-SO ₄ ^2– are almost independent of NO _x concentration and radiation field. If dimethylsulfoxide (DMSO or CH₃S(O)CH₃) is produced by the addition reaction and further converted to sulfuric acid (H₂SO₄) in an aqueous solution of cloud droplets, the oxidation process of DMSO might be important for the production of aerosol particles containing nss-SO ₄ ^2– at high latitudes.  相似文献