塔克拉玛干沙漠南缘绿洲沙物质粒度特征

运用沉积物的粒度分析方法，研究了塔克拉玛干沙漠南缘绿洲不同类型沙样的粒度参数、粒度频率分布、平均粒径对标准差特性图等粒度特征及其空间关系，为查明沙源物质的性质和风力作用状况，分析风沙运动及风沙地貌形成，建立绿洲防护体系提供依据。     

Test of Hack's slope to bed material relationship in the Southern Eifel Uplands,Germany

The local reach gradient of small gravel bed rivers (drainage area 0-8-110 km²) in the Eifel, West Germany, is adjusted to transport the river bed sediments. Transport of gravel becomes possible under high flow conditions (Shields entrainment factor ≈-03). Mean bed material size for riffle sections increases with distance downstream. For small drainage areas channel slope is a negative exponential function of drainage area, while for the larger region the additional influence of bedload size has to be considered. Good agreement with Hack's data (1957) for Virginia and Maryland, U.S.A., is achieved (S = 0.0066 (D₅₀/A)^{- 40.}, r = 0.67).     

The New Meteorite Fall of Yanzhuang—A Severely Shocked H6 Chondrite with Black Molten Materials

At 21:45 hr (Beijing time) on Oct. 31, 1990 the Yanzhuang meteorite hit the ground at the Yanzhuang village, Wenyuan County, Guangdong Province. Several fragments, totalling 3.5 kg, were recovered during the field survey. This meteorite is a rare one of its kind due to its heavily shocked features and thick veins made up of black molten materials. Olivine and low-calcium pyroxene are compositionally homogeneous with Fa=18.59, Fs=16.35 and Wo=1.29. The chemical composition (total Fe=28.0%) and recrystallized texture of the chondritic mass show that the Yanzhuang is an H6 chondrite. The black molten materials occur in the form of blocks (up to 2×3×4 cm in size) and veins (0.1–15 mm in width), and contain a lot of rounded and elliptic FeNi-FeS blobs (up to 6–10 mm in length). The metal in these blobs exhibits distinct dendritic structure characteristic of rapid cooling. Unmolten and molten samples are very similar in chemical composition, fitting well with the average H-chondrites. Partial melting and FeNi/FeS-silicate separation have not been observed in the molten materials of the Yanzhuang. This project was financially supported by the Science Foundation of Guangdong Province.     

On the enhanced confining pressure aproach to the mechanics of reinforced soil

Summary A review is presented of conceptual approaches that are currently in use for interpreting the operation of reinforced soil. The concepts of enhanced confining pressure and of reduced normal tensile strains are found to be closely related to current experimental and theoretical investigations as well as to the design methodologies available at present for reinforced soil applications. Focusing on the enhanced confining pressure concept, analytical expressions are developed that allow the estimation of the value of equivalent confining stress increase when the properties of soil and reinforcement and the state of stresses acting on a cylindrical reinforced soil element are known. The derived expressions can also be utilized for estimating the soil-reinforcement friction angle from the results of triaxial tests on cylindrical samples reinforced with horizontal layers of reinforcement.     

Aggregate resources: Production and environmental constraints

Aggregates are produced from sand and gravel deposits or from bedrock sources. Production sites are numerous to minimize transport and are more and more in a competing land use position. Urbanization, while creating a market, also sterilizes deposits and pressures producers to relocate further from populated areas. Regulating and permitting quarries is an issue in regions with growing populations. This regulatory environment may cause exploitation schemes to evolve towards greater recycling, importing, and marine production, for example. These changes may be entirely attributable to increased environmental constraints on producing operations and not on conventional mining constraints such as overburden, ore grade, and costs of operation.     

砖混结构楼房的控制爆破拆除技术

以实例介绍了砖混结构楼房的控制爆破拆除技术，对楼房拆除爆破的坍塌方式、爆破参数及安全技术进行了分析和探讨。     

某些方解石单晶的光学质量评价

本文用光学方法检查了经野外地质工作者挑选过的天然方解石单晶的光学质量。发现部分晶体的光学均匀性很差,晶体中的光散射颗粒很多,不能满足作为光学介质的要求。     

陕西柞水—山阳成矿带中酸性小岩体的地球化学研究

本成矿带内中酸性小岩体均为浅成—超浅成相、高温条件下岩浆结晶的产物。根据岩体及矿床中硫同位素、铅同位素成分及全岩稀土元素组成特征,判断成岩物质来源于地壳深部或上地慢。来自岩浆熔体的热水溶液是导致成矿的重要因素。     

The importance of atmospheric input of terrestrial organic material to deep sea sediments

The concentrations of lipids were determined in atmospheric particle, gas and rain samples collected from the tropical North Pacific to assess lipid sources, transport mechanisms and fluxes to the ocean surface. Four lipid compound classes (aliphatic hydrocarbons, fatty alcohols, fatty acid esters, and salts) all unequivocally show a terrestrial vascular plant source. These aerosol lipids originate from wind erosion of Asian and American soils and direct emission from vegetation. The major fluxes result from rain rather than dry deposition. These fluxes are large enough to have a major potential impact on the inventory of terrestrially derived lipid material found in deep-sea sediments. This has been showm for n-alkanes, fatty alcohols, fatty acids, total lipids and for organic carbon. By comparing atmospheric and sediment trap fluxes with sediment accumulation rates, it is suggested that some biogenic terrestrial material is more protected from degradation than marine-derived material.     

论太行山构造岩浆带的岩浆来源及其成因

本文以太行山构造岩浆带及其东西两侧断陷盆地的地质特征及深部探测资料为依据，探讨远离俯冲板内构造岩浆带中岩浆的成因、来源及侵位机制。提出了韧性流变－岩浆隆起模式。认为在区域构造应力场和地幔位势差、密度差的控制下?隆升的造山带剥蚀物向两侧断陷盆地搬运，而中下地壳则沿深部向山根缓倾的韧性拆离带迁移到造山带的深部，并在拆离剪切作用及流体的参与下形成深熔岩浆，这种深熔岩浆，在沿陡倾剪切带上侵过程中，不断与中