Using Models of the Deep Structure of the Earth’s Crust and Upper Mantle Based on GOCE Gravity Data in Metallogenic Analysis

Izvestiya, Atmospheric and Oceanic Physics - Gravimetric data obtained by the GOCE spacecraft contributes to the development of global models of the deep structure of the Earth’s crust and...     

Additional Analytical Data for Gabbro, GOG-1

Additional data for gabbro, GOG-1, were determined by instrumental-neutron-activation analysis, atomic-absorption spectrometry, and semi-quantitative spectrographic analysis. F ratios calculated in the analysis of variance for 26 sets of data for elements determined by the three methods were not significant, and hence the elements are distributed homogeneously among the bottles. The agreement between our data and the averages previously published ranges from very good to poor. More analytical data are necessary to establish reliable estimates of the concentrations of elements in GOG-1 and in two other gabbros so that three gabbros may be available to geochemists for use as standards.     

华北东部地幔改造作用和置换作用:单斜辉石激光探针研究

对山东蒙阴古生代金伯利岩中石榴石方辉橄榄岩、河南鹤壁新生代玄武岩中 铬尖晶石方辉橄榄岩、山东栖霞新生代玄武岩中央晶石二辉橄榄岩和山东山旺新生代 玄武岩中尖晶石（富ＣｐＸ）二辉橄榄岩单斜辉石的常量、微量元素的研究和对比表明：华 北地块古生代稳定存在的克拉通岩石圈地幔在中、新生代其东部被具大洋地幔性质的 显生宙地幔不均匀地发生了置换作用,残存于南北重力梯度带（岩石圈减薄过渡带）上 的鹤壁浅部克拉通地幔除保存有置换作用前改造作用的丰富信息外,也包含有其深部 被置换后的地幔改造作用信息;郯庐断裂带东部栖霞的新生地幔仍保留有较多的大洋 地幔成分特征,而郯庐断裂带内山旺的新生地幔受后续地幔改造作用的影响有向大陆 地幔演化的趋向．发生于华北地块东部中、新生代的岩石圈巨厚减薄作用与地幔的置换 作用有关,由渐进的富ＣＯ_２流体或碳酸岩熔体对岩石圈地幔的交代改造作用以及由此 所引起的熔体抽取作用是完成新生地幔对古老地幔置换作用的关键．郯庐断裂带等岩 石圈深大断裂为地幔改造作用和地幔置换作用提供了良好的通道作用．     

柴北缘鱼卡地区中侏罗统石门沟组含煤层段沉积有机相分析

柴达木盆地北缘鱼卡地区中侏罗统石门沟组含煤段中发育有油页岩、煤、碳质泥岩和泥岩等富有机质细粒沉积.为了研究其沉积有机相的类型及煤和油页岩形成的控制因素,本文通过岩心观察、工业分析结合有机地球化学测试分析等方法将含煤段细粒沉积物划分为了类型A(三角洲平原沉积环境)、B(三角洲前缘-浅湖沉积环境)、C1(湖沼非油页岩亚相)及C2(湖沼油页岩亚相)四种类型,其中类型C1沉积物中发育煤,类型C2中发育油页岩,且煤较油页岩具有更高的含油率、水分、挥发分以及发热量值.有机质类型特征方面,沉积有机相类型A、B及C1沉积物有机质类型均为Ⅱ2-Ⅲ型、有机质来源均以陆源和混合来源两种有机质来源为主,而类型C2中主要为Ⅱ2型,以混合有机质来源为主;类型A及C2其沉积物有机质均处于未成熟阶段,而类型B和C1中有机质均处于未成熟-低成熟阶段;有机质保存条件方面,类型A沉积物主要形成于缺氧的淡水环境,类型B主要形成于贫氧-缺氧的淡水-半咸水环境,类型C1形成于贫氧-缺氧的淡水-半咸水环境,而类型C2则主要形成于缺氧的淡水-半咸水环境.其中类型B较类型A,类型C2较类型C1,其沉积物均形成于更为还原且盐度更高的水体环境中.石门沟组含煤段是煤和油页岩的形成层位,稳定的沉积环境、丰富的湖泊有机质来源、良好的保存条件及较少的陆源碎屑的稀释共同促进了类型C2中油页岩的形成,而丰富的陆源植物供给及良好的保存条件则促进了类型C1中煤层的形成.     

Cultures monoalgales: courte description et discussion d'une méthode permettant une observation à fort grossissement des cellules avant leur isolement à l'aide d'un emporte-pièce

A method allowing isolation of phytoplancton algae for unialgal cultures is briefly described. Advantages and limits of the method are discussed.     

Variation in Coronal Activity from Solar Cycle 24 Minimum to Maximum Using Three-Dimensional Reconstructions of the Coronal Electron Density from STEREO/COR1

Three-dimensional electron density distributions in the solar corona are reconstructed for 100 Carrington rotations (CR 2054?–?2153) during 2007/03?–?2014/08 using the spherically symmetric method from polarized white-light observations with the inner coronagraph (COR1) onboard the twin Solar Terrestrial Relations Observatory (STEREO). These three-dimensional electron density distributions are validated by comparison with similar density models derived using other methods such as tomography and a magnetohydrodynamics (MHD) model as well as using data from the Solar and Heliospheric Observatory (SOHO)/Large Angle and Spectrometric Coronagraph (LASCO)-C2. Uncertainties in the estimated total mass of the global corona are analyzed based on differences between the density distributions for COR1-A and -B. Long-term variations of coronal activity in terms of the global and hemispheric average electron densities (equivalent to the total coronal mass) reveal a hemispheric asymmetry during the rising phase of Solar Cycle 24, with the northern hemisphere leading the southern hemisphere by a phase shift of 7?–?9 months. Using 14 CR (\(\approx13\)-month) running averages, the amplitudes of the variation in average electron density between Cycle 24 maximum and Cycle 23/24 minimum (called the modulation factors) are found to be in the range of 1.6?–?4.3. These modulation factors are latitudinally dependent, being largest in polar regions and smallest in the equatorial region. These modulation factors also show a hemispheric asymmetry: they are somewhat larger in the southern hemisphere. The wavelet analysis shows that the short-term quasi-periodic oscillations during the rising and maximum phases of Cycle 24 have a dominant period of 7?–?8 months. In addition, it is found that the radial distribution of the mean electron density for streamers at Cycle 24 maximum is only slightly larger (by \(\approx30\%\)) than at cycle minimum.