地幔交代作用的微区微量元素证据——云南双沟蛇绿岩的质子探针研究

用质子探针技术对双沟地幔交代熔融物的微区微量元素进行了测定。研究表明,地幔橄榄岩中的残留矿物橄榄石和斜方辉石仅含Ni和Zn,而Ga、Ge、Sr、Rb、Zr、Y、As、Pb等微量元素主要集中在地幔部分熔融所产生的矿物(尤其是尖晶石和绿泥石)中。微区范围内微量元素的分布表明,尖晶石二辉橄榄岩地幔不均一性的尺度可达微米级,通常解释为尖晶石二辉橄榄岩在开放系统下地幔交代作用的结果。     

北秦岭南缘弧前盆地沉积作用及盆地发展

秦岭被商丹缝合带分为北秦岭和南秦岭两个部分,在北秦岭南缘残留着与俯冲作用相关的岛弧火山岩以及弧前沉积体。对沿海丹带两个地区(黑河地区和黑山地区)弧前沉积体岩相组合和相序的研究显示,它们主要由深水浊积岩系。火山碎屑岩,扇三角洲沉积以及局限性台地碳酸盐岩和陆棚碎屑岩组成。总的沉积序列显示向上变浅趋势,但在弧前内侧边缘则表现为向上变深趋势。两个不同地区岩相和相序的差异明显受物源、海平面变化以及特别是构造作用的挫制。深水浊积岩系所反映的线状物源供给形式、扇三角洲体系的发育和其内部不同沉积段反复重叠的特征指示一种活动构造环境。弧前区构造发展一方面与其前部加积或下部垫底作用有关,另一方面则在很大程度上受由斜向俯冲而导致的伸展作用的影响。     

Another Source of Atmospheric Methane

The atmospheric concentration of methane is steadily increasin.Lacking of precise estimates of source and sink strengths for the atmospheric methane severely limits the current understanding of the global methane cycle.Agood budget of atmospheric methane can enhance our understanding of the global carbon cycle and global climate change,The known estimates of the main source and sink strengths are gresented in this paper,In terms of carbon isotopic studies,it is evidenced that the earth‘s primodial methane,which was trapped in the earth during its formation,may be another source of methane,with extensive,earth‘s degassing which is calleld the “breathing“ process of the earth and played an important role in the formation of the promitive atmosphere,large amounts of methane were carried from the deep interior to the surface and then found its way into the atmosphere.     

江西利山金矿床地质特征及控矿构造

本文较系统地阐述了利山金矿床的各项地质特征，并重点就控矿构造问题进行了总结讨论，认为ＮＷＷ向断裂带严格控制了所有金矿体的产出。ＮＮＥ、ＮＮＷ向断裂与ＮＷＷ向断裂带的交汇部位控制了富矿段的产出。在此基础上初步探讨了矿床成因及找矿方向，这对该地区的找矿评价和开发均具有实际意义     

甘肃敦煌-北山早前寒武纪岩石组合-构造初步框架

甘肃敦煌－北山地区广泛出露早前寒武纪岩石。这些岩石在早期的《甘肃省区域地质志》中被确定为前长城系、长城系、奥陶－志留系及部分石炭系。本文认为这些岩石应属太古宙和古元古代。据此，重新厘定了该区早前寒式纪岩石－构造框架。自南向北划分为敦煌太古宙杂岩区、北山南带古元古代剪切构造区和北山北带古元古代－太古宙杂岩区，并根据变形特点和岩石组合，进一步划分出次级带。     

西昆仑山南侧甜水海湖岩芯铁变化的环境记录

阐述了青藏高原西昆仑山南侧甜水海湖岩芯沉积物中氧化铁的丰度、频率分布和富集系数的变化规律。其丰度值范围FeO0．39％-3.95％，平均值为1．25％；Fe2O30．44％－8．09％，平均值为2．60％；Fe2O3／FeO0．21－3．60，平均比值1．12。说明该彻岩芯沉积物中铁平均丰度值较低，但其变化幅度较宽且清楚，在一定程度上反映了古气候环境具有较大幅度的波动。变异系数值表明，该湖岩芯沉积物中FeO的离散程度较Fe2O3大。大约距今23万年来氧化铁的沉积地球化学特征可划分出7个环境演化阶段，并基本上可与深海氧同位索阶段对比。揭示了甜水海湖演化与青藏高原强烈隆升引起的气候环境改变的密切关系。在距今23一15万年，沉积以河流相或冲积、洪积相为主，沉积环境以氧化环境为主导，气候以温干型波动；在距今15－7．4万年，沉积以湖相为主，沉积环境以还原环境为主导，气候以温湿型为主；在距今74万年以来，湖盆沉积环境多样化，沉积物以湖相和近源冲积、洪积相交替出现。气候出现冷湿、冷干、温湿和温干多种波动模式。这些资料分析初步认为甜水海古湖大约形成于距今15万年，即青藏高原第三成湖期，这也与青藏高原在距今15万年左右的再次构造隆升有关。     

The law of dislocation between two sides of active faults in China and their geodynamic force

By contrasting and analyzing the characteristics of gravity field nearby some important active faults in the continent of China, it can be found that the crust blocks where Bouguer anomalies are regionally positive (or relatively positive) are moving towards the terrestrial poles and the blocks where Bouguer anomalies in a tremendous area are negative (or relatively negative) are moving towards the equator. By analysis of mechanics and mathematics calculation and based on lots of practical data, the authors hold that the change in density of a crust block is a decisive factor that causes the horizontal movement of the continental crust, while magma activity is an important factor that leads to the change in density of a crust block.     

Global modelling study (GSM TIP) of the ionospheric effects of excited N2, convection and heat fluxes by comparison with EISCAT and satellite data for 31 July 1990

Near-earth plasma parameters were calculated using a global numerical self-consistent and time-dependent model of the thermosphere, ionosphere and protonosphere (GSM TIP). The model results are compared with experimental data of different origin, mainly EISCAT measurements and simultaneous satellite data (N_e and ion composition). Model runs with varying inputs of auroral FAC distributions, temperature of vibrationally excited nitrogen and photoelectron energy escape fluxes are used to make adjustments to the observations. The satellite data are obtained onboard Active and its subsatellite Magion –2 when they passed nearby the EISCAT station around 0325 and 1540 UT on 31 July 1990 at a height of about 2000 and 2200 km, respectively. A strong geomagnetic disturbance was observed two days before the period under study. Numerical calculations were performed with consideration of vibrationally excited nitrogen molecules for high solar-activity conditions. The results show good agreement between the incoherent-scatter radar measurements (N_e, T_e, T_i) and model calculations, taking into account the excited molecular nitrogen reaction rates. The comparison of model results of the thermospheric neutral wind shows finally a good agreement with the HWM93 empirical wind model.     

ASPI experiment: measurements of fields and waves on board the INTERBALL-1 spacecraft

The plasma-wave experiment ASPI (analysis of spectra of plasma waves and instabilities) on board the INTERBALL spacecraft is a combined wave diagnostics experiment. It performs measurements of the DC and AC magnetic field vector by flux-gate and searchcoil sensors, the DC and AC electric field vector by Langmuir double probes and the plasma current by Langmuir split probe. Preliminary data analysis shows the low noise levels of the sensors and the compatibility of new data with the results of previous missions. During several months of in-orbit operation a rich collection of data was acquired, examples of which at the magnetopause and plasma sheet are presented in second part of the paper.     

下辽河坳陷现代应力场特征

本文通过辽河油田的钻孔崩落资料及小地震震源机制解，推断出辽河坳陷地区现代构造应力场的特征。两种方法得到的结果基本一致，即区域应务场和局部应力场的结果一致，该地区处于走滑断层型应力状态。