电离层诸参量对大气重力波的响应与重力波参数反演

本文利用欧洲非相干散射雷达数据,分析研究了电离层不同等离子体参量对大气重力波的响应之间的关系.应用这种关系,发展了一种在垂直于地磁场的电场可以忽略等简化假设下,由电子密度和离子沿场速度的同时测量数据,反演求解较高（约250km以上）F区中引起TID的重力波传播参数的方法.用此法对一典型TID事件进行分析计算,所得结果与全波解数值研究结果很好符合.     

Stratigraphic record and palaeogeographical context of the Neogene basins in the Betic Cordillera, Spain

The Betic Cordillera (Southern Spain) acquired its present configuration during the Neogene. The formation, evolution and total or partial destruction of Neogene sedimentary basins were highly controlled by the geodynamic situations and the positions of the basins in the Betic Cordillera. It is impossible to reconstruct the geometry of basins formed during the Early and Middle Miocene, concurrently with the westward drift of the Internal Zones, because in many cases only small outcrops remain. The basins formed on the mobile substratum (the Internal Zones) are characterized by a sedimentary infill made up of synorogenic deposits, which were intensely deformed towards the end of the Middle Miocene, and which were heavily eroded before the beginning of the Late Miocene. In the External Zones, deposition mainly took place in the North Betic Strait, an area across which there was wide communication between the Atlantic and the Mediterranean, which received huge olistostromic masses in its more mobile sector (the foredeep basin), and which evolved differently in its eastern and western sectors. The palaeogeography of the Cordillera changed radically at the beginning of the Late Miocene, when the westward drift of the Internal Zones ceased. During this time the North Betic Strait disappeared and, in what had been its northwestern half approximately, the Guadalquivir Basin became individualized. This basin, which was located between the Betic Chain and the emerged Hercynian Massif, acquired a structure similar to that of the present basin and its extension was also similar to that of the present Neogene outcrops. Intramontane basins became individualized in the recently formed and progressively emerged mountain chain, reaching a development and size in this Cordillera much greater than in other Alpine chains. These basins are characterized by their thick infills, which are unconformable on the folded and deformed substratum, and which can be subdivided according to the different movements of the fault sets that controlled their evolution.     

柴北缘冷湖构造带古近系沉积体系及演化特征

通过对柴达木盆地北缘西段重点探井的岩心观测、重矿物分析、测井数据及地震资料的分析，研究了冷湖构造带古近系沉积体系及演化特征和不同时期沉积微相及砂体的展布规律.结果认为，冷湖构造带古近系主要发育冲积扇-辫状河-辫状河三角洲-湖泊沉积体系，物源来自北东方向的小赛什腾山和赛什腾山附近.古近系路乐河组（E₁₊₂）沉积期，主要发育辫状河以及辫状河三角洲平原沉积，仅在靠近山前发育少量冲积扇沉积；至下干柴沟组（E₃）沉积时期，主要发育辫状河、辫状河三角洲平原、辫状河三角洲前缘及滨-浅湖沉积.古近纪时期冷湖构造带表现为一次较大规模的水进过程，纵向沉积继承性明显，很好地记录了这一沉积演化过程.这一沉积体系及演化过程有利于粗碎屑和细碎屑交互沉积，形成较好的储盖组合，为柴达木盆地冷湖构造带下一步的油气勘探提供了可靠的地质依据.     

Lateritic nickel deposits of Brazil

Many nickel deposits are known in Brazil, accounting for about 350 · 10⁶ tons of ore with an average of 1.5% Ni. All are of the lateritic type. These deposits are scattered throughout the country, being rarer in the Northeastern Region and in the South, below 25 °S latitude. They are mainly associated with mafic-ultramafic massifs of large dimensions and ultramafic alkaline complexes, and occur in climatic regions of contrasting seasons. The weathering profile developed over the fresh rock consists, from bottom to top, of the following horizons: altered rock, coarse saprolite, argillaceous saprolite, ferruginous saprolite and lateritic overburden. The thickness of each horizon varies from one deposit to another, the whole profile generally exceeding 20 m. The saprolitic horizons with inherited minerals (serpentine, chlorite) or neoformed minerals (smectites) constitute the silicated nickel ore and are thicker were climatic conditions are drier; the ferruginous upper horizons made up of iron oxide-hydroxides are more developed in more humid regions. In Brazil, the silicated ore generally prevails over the oxidized ore. The main Ni-bearing minerals are serpentine, smectite, garnierite and goethite. The lateritic nickel deposits of Brazil may be correlated with two erosion surfaces, corresponding to the Sul Americano (Lower Tertiary) and Velhas (Upper Tertiary) levelling cycles. The degree of dismantling of the higher and more ancient surface and the consequent development of the Velhas Surface control the position of the nickel accumulation in the landscape. Thus, the deposits may be found either in the lowlands or in the highlands, where they are always covered by a silcrete layer. The alteration profiles in the Brazilian lateritic nickel deposits are broadly similar to those described elsewhere in the world. However, they present two characteristic features: the silicated ore prevails over the oxidized ore, and a silicified layer covers the profies developed on the highlands.     

The eclogitized pillows of the Betic Ophiolitic Association: relics of the Tethys Ocean floor incorporated in the Alpine chain after subduction

In the volcanic sequence of the Betic Ophiolitic Association (BOA) volcanic structures and textures are preserved in spite of being metamorphosed to the edogite facies. The original quenched glassy margins of the pillows and lava flows are still recognizable by the darker colour, fine-grained textures and scarcity of phenocrysts. The BOA eclogitized pillows have chemical compositions very similar to the basalts enriched in LIL elements erupted nowadays at the mid-oceanic ridges. Magmatism which generated the BOA most likely began under continental rift conditions at the Triassic-Jurassic boundary and continued under ocean-floor extensional conditions during the lower and middle Jurassic. In age and petrological characteristics this magmatism is equivalent to that of the western Tethys ophiolites. During the Late Cretaceous, due to the collision of African and Iberian Plates, the BOA ophiolites were subducted and underwent a metamorphism in the eclogite fades whose climax in the Lugros outcrop can be estimated at 650–700°C and about 20 kb.     

Structural elements in southeastern Quebec,northwestern Appalachians,Canada

An attempt is made to correlate and separate in terms of style and time two contrasting sets of structural elements in the northwestern part of the Appalachian Uplands in the Province of Quebec, Canada. There is sufficient evidence to indicate that a fold system with north-south trending axes is superimposed on a fold system with east-west axes. It is suggested that the two sets of structures represent pulses of one long-continued deformation accompanied by corresponding early and late phases of metamorphism.

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Zusammenfassung Es wurde versucht, in den Appalachen des südöstlichen Teiles der Provinz Quebec, Kanada, zwei ungleichzeitige tektonische Systeme verschiedenen Baustils zu trennen. Die komplexen Kleinstrukturen zeigen, da\ Ost-West streichende Faltenachsen von einer jüngeren Nord-Süd-Faltung überprägt worden sind. Der Autor ist der Meinung, da\ die zwei tektonischen Systeme, die von einer frühen und späten Phase der Metamorphose begleitet werden, den zeitlich getrennten Verformungsstadien einer Orogenese entsprechen.