水热爆炸归因浅析

经对发生水热爆炸频率高、强度大的西藏、云南温泉进行研究，发现水热爆炸与温泉中硅浓度高有关。认为硅氢化物从地壳深部，通过深断裂系统，迁移至地壳浅部，被氧化、水解生成硅胶，逐渐将围岩和出口胶结形成一个相对封闭的系统，致使以后迁来的硅氢化物、硼氢化物、其它氢化物及热能逐渐积蓄，当温度、压力、氢化物浓度达一定限度时，冲破封闭层，氢化物迅速被氧化，产生大量热、气，发生水热爆炸。     

硼氢化物是形成硼矿床的重要迁移形式

经对硼氢化物的形成条件、内生硼矿物化学成分、矿物共生组合及盐湖卤水、热泉的有关物质浓度值研究后 ,认为硼氢化物是形成硼矿床的重要活化、迁移形式     

论原始海洋水的酸碱度

通过对地球各圈层岩性、流体演化特征及类地行星岩石、大气特征的考察 ,对产生酸碱机理及生物生存繁衍进化基本条件的研究 ,认为古地球强还原性原始海水偏碱性。强还原性的古地球无Cl2 、F2 等强氧化剂物质存在 ,无由它们直接产生HCl、HF的可能 ;氮主要以N2 、NH3 形式存在 ,硫呈S2 -、S2 -2 、S0 形式存在 ,碳主要呈碳氢化合物、碳的低价氧化物、C0 等还原态存在 ,缺游离氧将它们氧化成高价而产酸。而大量基性、超基性岩浆喷溢出地表使原始海洋水呈碱性 ,由于碱金属、碱土金属及其合金氢化物与硅的氢化物一同迁移至地表 ,即使含硅很高的酸性岩其热液流体也呈碱性。     

人类可望从月球获取能源

中国科学院院士、中国探月工程首席科学家欧阳自远说，科学技术的发展，将使月球上两种资源给地球能源问题带来希望：一是月球的太阳能；二是月壤中气体，如氢、氦、氖、氩、氮等资源，尤其是核聚变燃料氦-3。     

论述冲击陨石对单质金属铁形成条件的约束

自Apollo时代开始,单质金属铁就作为月球等无大气行星体表面太空风化作用的特征产物而受到普遍关注。单质金属铁的形成能够显著改变无大气行星体的反射光谱特征,对准确解译行星体光谱数据具有重要意义。目前缺乏对于单质金属铁形成条件的深入研究与探讨。基于此,本文拟论述陨石的冲击特征对空间环境中单质金属铁形成条件的约束作用,进而对空间环境中太空风化作用过程有更深刻的理解。     

“地球在宇宙中”一章的部分知识剖析

太阳是太阳系的中心天体,形成于50亿年前,它是一颗普通恒星。太阳系中的九大行星及其他天体都环绕太阳运行,太阳是整个太阳系光和热的主要来源。太阳同所有的恒星一样,由炽热气体构成,主要成分是氢,约占71%,其次是氦,约占27%。太阳的中心为核反应区,在氢核聚变成氦核的反应中产生巨大的能量．并以辐射方式由内向外传送。     

广东发现两处巨型铷矿资源量逾360万吨

近日从广东省国土资源厅获悉,经过近3年努力,该省相继在武夷成矿带广东南段的紫金县、蕉岭县发现罕见巨型铷矿产地,两处估算铷资源量达360万吨以上。铷是稀有金属,其氢化物和硼化物可作为高能固体燃料,在航天航空、能源、国防工业的应用不断扩大,在玻璃、陶瓷等民用工业领域应用前景广阔。铷的元素活泼、熔点低、沸点低,利用其特性有可能把热能直接变为电能。     

苏联学者谈大洋的起源和发展

苏联学者认为,大洋的起源与地壳的形成有关。地壳的形成是以地球最初的增温为条件,而这种增温是由于地球内部放射性元素裂变的结果。因此,便发生了最初的物质状态的变化,从而导致地壳的形成。根据维诺格拉多瓦的理论,玄武岩成份的易熔阶段最能形成原始地壳。地幔形成基岩,这是组成玄武岩地壳成份的易熔化合物经过分离后而形成的残余产物。各种气体和易熔物质上升到地表,便开始产生了水圈和大气圈。     

湿地生态系统碳储存和温室气体排放研究

湿地生态系统是地球上重要的有机碳储库, 湿地植被和土壤碳储量丰富、碳密度高。湿地还是CO₂、CH₄和N₂O等温室气体的源和汇。近百年来,由于土地利用,特别是农业开发和泥炭开采,导致大面积湿地被排干,并排放大量温室气体。多项研究表明湿地保护和恢复能促进碳积累和减少温室气体排放,通过对国内外有关文献的分析,针对近年来科学界普遍关注的湿地生态系统碳储量、碳平衡和土地利用对温室气体排放的影响、湿地与全球气候变化关系等方面的问题进行了初步探讨。     

火山活动对全球气候变化的影响

火山活动是影响全球气候变化的重要因子之一.强烈的火山喷发会向大气圈排放大量的火山灰、水蒸气和SO2等气体,尤其是SO2能在平流层中形成气溶胶,并停留很长时间,减少太阳对地表的辐射量,影响局地或全球气候.地质历史记录表明,火山活动与气候冷期有密切的联系,现代观测和模拟资料也显示火山活动后的一年至几年内,火山周围地区甚至全球产生不同程度的降温.现有研究表明,在火山喷发的活跃时期,火山气体喷发物对地球气候系统的影响程度可能超过CO2等气体产生的温室效应.     

氢化钠的合成、性质及应用

氢化钠是一种十分重要的无机及有机合成试剂,在精细化工领域应用广泛。由于其反应活性与纯度和分散度密切相关,近年来人们对合成高活性氢化钠的研究日趋重视。氢化钠的制备已有多种方法的报道,其中以油液分散金属钠法是可以实现工业化的重要工艺。论述了氢化钠的几种合成方法,叙述了氢化钠的性质,并简介了其应用情况。     

中国稀土对外贸易格局演化及影响因素

从中美贸易摩擦到“科技冷战”以来,被誉为“高科技命脉”的稀土,日益成为国际博弈的前沿领域。在此背景下,厘清中国稀土进出口贸易流动态势、把握中国在国际稀土市场中的地位变动,对中国资源安全格局的整体优化和科技自立自强的长久维持具有一定意义。本文基于2008—2018年中国稀土进出口贸易数据、相关国家社会经济政治指标及联合国投票数据,借助相互依存指数、地缘亲和度模型、GIS空间技术以及负二项面板回归等手段,探讨了中国稀土产品对外贸易格局的演化及影响因素。研究发现：① 中国稀土贸易存在较大波动,出口额远大于进口额,整体呈现“升—降—升”发展态势。② 中国稀土进口市场高度集中且路径依赖增强,出口市场逐步多元且路径依赖减弱。中国主要出口具有较高附加值的中、下游产品,进口具有较低附加值的上游矿物类产品。③ 中国在全球稀土贸易相互依存格局中的优势地位整体强化。中国与多数友好型国家间的相互依存关系呈现优化态势,但与美国、加拿大、澳大利亚等分歧型国家之间的相互依存关系呈现恶化态势。④ 国家主体属性、国家间邻近性以及中国的贸易政策、贸易环境等对中国稀土对外贸易产生重要影响。     

Elementary forms for land surface segmentation: The theoretical basis of terrain analysis and geomorphological mapping

Land surface morphology is fundamental to geomorphological mapping and many GIS applications. Review and comparison of various approaches to segmentation of the land surface reveals common features, and permits development of a broad theoretical basis for segmentation and for characterization of segments and their boundaries. Within the context of defining landform units that maximise internal homogeneity and external differences, this paper introduces the concept of elementary forms (segments, units) defined by constant values of fundamental morphometric properties and limited by discontinuities of the properties. The basic system of form-defining properties represents altitude and its derivatives, constant values of which provide elementary forms with various types of homogeneity. Every geometric type of elementary form can be characterized by a defining function, which is a specific case of the general polynomial fitted function. Various types of boundary discontinuity and their connections and transformations into other types of morphological unit boundaries are analysed.The wealth of types of elementary forms and their boundaries is potentially unbounded and thus is sufficient to cover the real variety of landforms. Elementary forms in the basic set proposed here have clear potential for genetic and dynamic interpretation. A brief worked example documents the possibility of analytical computation of various models of ideal elementary forms for particular segments of landform. Ideal elementary forms can be considered as attractors, to which the affinity of surface segments can be measured by multivariate statistical methods. The use of the concept of elementary forms in landscape segmentation is promising and it could be adapted for elementary segmentation of various other spatial fields.     

舟山群岛北部的地理环境与黄棕壤的形成——兼论新构造运动影响及红壤带的北界问题

舟山群岛北部历来划属红壤带,但良好发育且分布最广的是黄棕壤,因其多种性状与气候等环境酷似南京下蜀黄土上的典型黄棕壤。黄棕壤上无红化迹象,不能以下部有酸性古红土而将本区误定为红壤带。第四纪以来地球上有过多次气候波动,使红壤带的北界南北摆动。红壤带在目前不一定有红壤化作用在进行,它仅表示为红壤相对集中的地带。本文还讨论了该黄棕壤形成过程中,新构造运动在多方面的重要影响。     

Vacation Field Work for Pupils

Abstract

A Magic Carpet Trip to Learning Geography provides successful hands on, student-tested activities for teaching elementary school students about continents and oceans. From the introductory “Magic Carpet” poem to the finale, Geography Pizza, students are activiely involved in learning: (1) why our earth is the “Blue Planet”; (2) the continent names, shapes, and locations; (3) about continental drift. In the article an evaluation tool is discussed that can be used to assess the growth of geography awareness in the classroom. Through the use of poetry, music, games, science, math, cooking, and student writing, geogrpahy comes alive in the elementary classroom.     

稀土元素在残积景观剖面中的垂直分异与矿物组成的关系——以赣南富稀土地理景观为例

选择赣南稀土矿区典型地理景观,主要研究了表生作用过程中稀土元素与矿物组成的关系。结果表明景观中稀土元素的含量分布与土体的机械组成密切相关。不同粒级组分中稀土元素的含量有以下序列:粗粉粒(20～63μm)≥细粉粒(2～20μm)>粘粒(<2μm)>沙粒(0.063～1mm)>石砾(>1mm).石英和长石对稀土元素起稀释的作用,高岭石、埃洛石等次生层状硅酸盐矿物对稀土元素具有吸附富集作用,重矿物对稀土元素分布也有一定的影响。     

Mineralogic and Diagenetic Controls on Reservoir Quality of Paleozoic Sandstones,Gebel El-Zeit,North Eastern Desert,Egypt

Natural Resources Research - Studying the mineral composition and petrophysical properties of the Cambro–Ordovician sequence in Gebel El-Zeit indicates that it can be discriminated into four...     

3-D seismic velocities calculated from lattice-preferred orientation and reflectivity of a lower crustal section: examples of the Val Sesia section (Ivrea zone, northern Italy)

To quantify the seismic properties of lower crustal rocks and to better constrain the origin of the lower crustal seismic reflectivity, we determined the complete 3-D seismic properties of a lower crustal section. Eight representative samples of the main lithologic and structural units outcropping in the Val Sesia (Ivrea zone) were studied in detail. The seismic velocities were calculated using the single crystal stiffness coefficients and the lattice preferred orientation (LPO) of each mineral in all samples. The 21 stiffness coefficients characterizing the elastic behaviour of each rock are determined. Mafic and ultramafic rocks such as pyroxenite and pyroxene-bearing gabbros display complex shear wave properties. These rocks are weakly birefringent (maximum 0.1 kms⁻¹) and it is difficult to find consistent relationships between the seismic properties and the rock structure. On the other hand, seismic properties of deformed felsic rocks are essentially controlled by mica. They display strong S -wave birefringence (0.3 km s⁻¹) and relatively high V _p anisotropy (7.6 per cent). Amphibole also strongly influences the rock birefringence patterns. For both kind of rocks, the foliation is highly birefringent and the fast polarized shear wave is systematically oriented parallel to the foliation. We show that the number of mineral phases in the rock strongly controls the anisotropy. The seismic anisotropy has a complex role in the P -wave reflectivity. Compared to the isotropic case, anisotropy enhances the reflection coefficient for about 60 per cent of the possible lithological interfaces. For 40 per cent of the interfaces, the reflection coefficient is much lower when one considers the medium as anisotropic.     

Using evidence of non-linear induced polarization for detecting extended ore mineralizations

The discrimination between electrolytic and electronic conductors is highly relevant to geological modelling as it allows conclusions to be drawn about the formation and mineral composition of rocks. The induced polarization (IP) method, which compares the electric current injected into the ground with the corresponding earth potential differences can be used for this purpose.
  This paper describes a new method based on the theory that non-linear electrochemical processes on the surface of electronic conductors are responsible for non-linear IP (NLIP) phenomena. This results in multiples of the fundamental frequency being observed in the telluric voltage spectra when a monochromatic current signal is fed into the ground. The non-linearity of the current–voltage characteristic is most effectively described by a spectral method.
  A laboratory experiment was carried out, using an electrolytic trough with a small graphite cylinder serving as an electronic conductor, which clearly demonstrated the validity of the method. A field experiment was undertaken at a borehole of approximately 450  m depth, located in the transition zone of the Tepla-Barrandium and Moldanubicum in East Bavaria. A sinusoidal current was injected into the ground using a logging tool at depths varying between 150 and 450  m. The corresponding potential differences were simultaneously observed along a profile on the surface. Field and laboratory results show a striking similarity. It can be concluded that an extensive electronic conductor—probably graphite—is steeply dipping southwards meeting the borehole at approximately 310  m depth.     

粘土矿物在过去环境变化研究中的应用

粘土矿物是一种广泛分布于地表的沉积物,其组合及含量的变化记录了源区过去气候环境变化的信息。因此,可以根据粘土矿物的含量和组合变化等信息推知其形成时期的气候环境,重建古环境,揭示气候环境演变的规律。粘土矿物是一种研究古环境演化重要的代用指标,在过去气候环境变化研究中有广阔的应用前景。