JX—3解析测图仪上航测高倍放大成图的试验

介绍试用１：３３０００比例尺航测资料，在ＪＸ－３解析测图仪上高倍放大航测１：１０００比例尺地形图的成图方案和应采取的技术措施，运用 解析法模型绝对定向的原理，在全野布点时采用两种方案对照比较，进行理论和试验精度的分析，并给出试验结果。     

数字地震数据的处理研究—真实地面运动的复原

讨论了在频域中真实地面运动的复原问题，借助于一个稳定的六阶带通滤波器可使地震仪反演系统趋于稳定，最后由关分方程递归求出真实地动位移，结果表明，对同一个地震，不同的仪器其原始响应不同，但由其复原的真实地面运动结果却有相当好的一致性。这证明了所采用的复原方法的可用性。     

热力强迫对越赤道气流产生和维持的作用——定性分析

从原始方程出发，应用大气运动的对称反对称性理论，就赤道地区一呈偶极子分布的反对称冷热源对越赤道气流的形成和维持作用进行了定性分析。结果表明，非绝热加热的反对称分布对越赤道气流的影响是通过诱发和维持反对称的气压场分量来实现的。即在热源上空低层形成低压，高层形成高压；在热汇上空形成相反的气压场。这样，在赤道上空高、低层就将形成与相应气压梯度方向一致的越赤道气流     

Ultra-high-temperature metamorphism and multistage decompressional evolution of sapphirine granulites from the Palni Hill Ranges, southern India

Sapphirine granulites from a new locality in the Palni Hill Ranges, southern India, occur in a small enclave of migmatitic, highly magnesian metapelites (mg=85–72) within massive enderbitic orthogneiss. They show a variety of multiphase reaction textures that partially overprint a coarse-grained high-pressure assemblage of Bt+Opx+Ky+Grt+Pl+Qtz. The sequence of reactions as deduced from the corona and symplectite assemblages, together with petrogenetic grid considerations, records a clockwise P–T evolution with four distinct stages. (1) Equilibration of the initial high-P assemblage in deep overthickened crust (12 kbar/800–900 °C) was followed by a stage of near-isobaric heating, presumably as a consequence of input of extra heat provided by the voluminous enderbitic intrusives. During heating, kyanite was converted to sillimanite, and biotite was involved in a series of vapour-phase-absent melting reactions, which resulted in the ultra-high-temperature assemblage Opx+Crd+Kfs+Spr±Sil, Grt, Qtz, Bt, coexisting with melt (equilibration at c. 950–1000° C/11–10 kbar). (2) Subsequently, as a result of decompression of the order of 4 kbar at ultra-high temperature, a sequence of symplectite assemblages (Opx+Sil+Spr/Spr+Crd→Opx+Spr+Crd→Opx+Crd→Opx+Crd+Spl/Crd+Spl) developed at the expense of garnet, orthopyroxene and sillimanite. This stage of near-isothermal decompression implies rapid ascent of the granulites into mid-crustal levels, possibly due to extensional collapse and erosion of the overthickened crust. (3) Development of late biotite through back-reaction of melt with residual garnet indicates a stage of near-isobaric cooling to c. 875 °C at 7–8 kbar, i.e. relaxation of the rapidly ascended crust to the stable geotherm. (4) A second period of near-isothermal exhumation up to c. 6–5 kbar/850 °C is indicated by the partial breakdown of late biotite through volatile phase-absent melting reactions. Available isotope data suggest that the early part of the evolutionary history (stages 1–3) is presumably coeval with the early Proterozoic metamorphism in the extended granulite terrane of the Nilgiri, Biligirirangan and Shevaroy Hills to the north, while the exhumation of the granulites from mid-crustal levels (stage 4) occurred only during the Pan-African thermotectonic event, which led to the accretion of the Kerala Khondalite Belt to the south.     

柏井采空区地基注浆加固技术

通过目前国内外现有资料的对比研究，对严重影响石太高速公路修建和运营的柏井采空区采用压力注浆的方法，充填采空区上覆的裂隙冒落带，以达到加固地基的目的。灌注材料选用水泥和粘土，水固比为１：１．５，依据地面构造物不同，在桥涵地段采用１：０．８：０．７（水：水泥：粘土，下同）的配比，在边坡地段采用１：０．５：１的与比，在一般路段采用１：０．３：１的配比，灌注浆液的结石体在采空区及上覆的裂隙冒落带中充填率达     

云南老王寨金矿煌斑岩地球化学研究中的某些问题──与宋新宇等同志商榷

本文对“云南老王寨金矿煌斑岩地球化学研究”一文中的部分结论及其解释，提出一些不同意见与原文作者宋新宇等先生商榷     

90年代世界贸易发展及空间格局变化的新特点

在世界贸易组织、日趋强烈的开放的区域主义倾向、跨国公司强劲的直接投资影响下，世界贸易正在经历着巨大变化，处在一个新的转换时期。本文从影响当今世界贸易发展的多重因素分析，揭示90年代世界贸易增长、内容结构以及空间格局发展变化的新特征，并展望世界贸易的未来发展。     

The Zihuatanejo, Mexico, earthquake of 1994 December 10 (M= 6.6): source characteristics and tectonic implications

An analysis of the Zihuatanejo, Mexico, earthquake of 1994 December 10 ( M = 6.6), based on teleseismic and near-source data, shows that it was a normal-faulting, intermediate-depth ( H = 50 ± 5 km) event. It was located about 30 km inland, within the subducted Cocos plate. The preferred fault plane has an azimuth of 130°, a dip of 79° and a rake of −86°. The rupture consisted of two subevents which were separated in time by about 2 s, with the second subevent occurring downdip of the first. The measured stress drop was relatively high, requiring a Δσ of about a kilobar to explain the high-frequency level of the near-source spectra. A rough estimate of the thickness of the seismogenic part of the oceanic lithosphere below Zihuatanejo, based on the depth and the rupture extent of this event, is 40 km.
This event and the Oaxaca earthquake of 1931 January 15 ( M = 7.8) are the two significant normal-faulting, intermediate-depth shocks whose epicentres are closest to the coast. Both of these earthquakes were preceded by several large to great shallow, low-angle thrust earthquakes, occurring updip. The observations in other subduction zones show just the opposite: normal-faulting events precede, not succeed, updip, thrust shocks. Indeed, the thrust events, soon after their occurrence, are expected to cause compression in the slab, thus inhibiting the occurrence of normal-faulting events. To explain the occurrence of the Zihuatanejo earthquake, we note that the Cocos plate, after an initial shallow-angle subduction, unbends and becomes subhorizontal. In the region of the unbending, the bottom of the slab is in horizontal extension. We speculate that the large updip seismic slip during shallow, low-angle thrust events increases the buckling of the slab, resulting in an incremental tensional stress at the bottom of the slab and causing normal-faulting earthquakes. This explanation may also hold for the 1931 Oaxaca event.     

古元古代变质作用及其构造成因模式综述

以Ｐ－Ｔ－ｔ轨迹为手段，有助于探讨变质作用随大地构造演化或变迁而动态演化的特点，本文主要讨论了古元古代普遍出现的低压高温变质作用、高压高温变质作用及其Ｐ－Ｔ－ｔ轨迹，而且讨论了高压低温变质作用在古元古代很少出现的原因。在此基础上，综述了以上各类变质作用的各种可能的构造成因模式。     

Rapid Variscan exhumation and the role of magma in core complex formation: southern Brittany metamorphic belt, France

ABSTRACT The high-grade migmatitic core to the southern Brittany metamorphic belt has mineralogical and textural features that suggest high-temperature decompression. The chronology of this decompression and subsequent cooling history have been constrained with ⁴⁰Ar/³⁹ Ar ages determined for multigrain concentrates of hornblende and muscovite prepared from amphibolite and late-orogenic granite sheets within the migmatitic core, and from amphibolite of the structurally overlying unit. Three hornblende concentrates yield plateau isotope correlation ages of c. 303–298 Ma. Two muscovite concentrates record well-defined plateau ages of c. 306–305 Ma. These ages are geologically significant and date the last cooling through temperatures required for intracrystalline retention of radiogenic argon. The concordancy of the hornblende and muscovite ages suggest rapid post-metamorphic cooling. Extant geochronology and the new ⁴⁰Ar/³⁹Ar data suggest a minimum time-integrated average cooling rate between c. 725 °C and c. 125 °C of c. 14 ± 4°C Ma^-1, although below 600 °C the data permit an infinitely fast rate of cooling. Mineral assemblages and reaction textures in diatexite migmatites suggest c. 4 kbar decompression at 800–750 °C. This must have pre-dated the rapid cooling. Emplacement of two-mica granites into the metamorphic belt occurred between 345 and 300 Ma. The youngest plutons were emplaced synkinematically along shallow-dipping normal faults interpreted to be reactivated Eo-Variscan thrusts. A penetrative, west-plunging stretching lineation developed in these granites suggests that extension was orogen-parallel. Extension was probably related to regional uplift and gravitational collapse of thermally weakened crust during constrictional (escape) tectonics in this narrow part of the Variscan orogen. This followed slab breakoff during the terminal stages of convergence between Gondwana and Laurasia; detachment may have been consequent upon a change in kinematics leading to dextral displacement within the orogen. Dextral ductile strike-slip displacement was concentrated in granites emplaced synkinematically along the South Armorican Shear Zone. Rapid cooling is interpreted to have resulted from tectonic unroofing with emplacement of granite along decollement surfaces. The high-grade migmatitic core of the southern Brittany metamorphic belt represents a type of metamorphic core complex formed during orogen-parallel extensional unroofing and regional-scale ductile flow.