永登县药水沟—红门寺地热资源综合勘查评价

药水沟—红门寺地热田位于兰州—民和盆地西缘 ,由药水沟、龙王沟温泉和红门寺地热孔组成。利用物化探指标对该地热勘查靶区筛选 ,对地热条件较好的药水沟进行地、物、化和水文综合勘查 ,查明了控制地热的地质构造背景和热水通道 ,提出下步开发建议     

云微物理参数在飞机积冰分析和预报中的应用研究

对飞机积冰预报的现状进行了分析 ,介绍了积冰预报中云微物理参数的应用概况 ,并就积冰预报中云微物理参数的应用前景进行了分析和讨论。将模式模拟和卫星反演的微物理参数引入飞机积冰分析和预报 ,将进一步提高飞机积冰预报的准确性和合理性     

Geochemistry and Petrogenesis of the Tongshankou and Yinzu Adakitic Intrusive Rocks and the Associated Porphyry Copper-Molybdenum Mineralization in Southeast Hubei, East China

Abstract. The late Jurassic Tongshankou and Yinzu plutons in southeast Hubei have been investigated for their contrasting metal mineralization features. The former is closely associated with porphyry Cu‐Mo mineralization, while the latter is barren of metal mineralization, althouth both are located very close to each other. The Tongshankou granodiorite porphyries and the Yinzu granodiorites are geochemically similar to adakites, e.g., high Al₂O₃ and Sr contents and La/Yb and Sr/Y ratios, enriched in Na₂O, depleted in Y and Yb, very weak Eu anomalies and positive Sr anomalies. However, different geochemi‐cal characteristics exist between the two plutons: the Tongshankou adakitic rocks (1) are relatively enriched in SiO₂, K₂O, MgO, Cr, Ni, and Sr and depleted in Y and Yb; (2) have higher degree REE differentiation; (3) have positive Eu anomalies in contrast with very weak negative or unclear Eu anomalies in the Yinzu rocks; and (4) isotopically have relatively higher eP_Nd(t) values (‐5.19 to ‐5.38) and lower initial ⁸⁷Sr/⁸⁶Sr ratios (0.7060 to 0.7062), while the Yinzu adakitic rocks have relatively lower eP_Nd(t) values (‐7.22 to ‐8.67) and higher initial ⁸⁷Sr/⁸⁶Sr ratios (0.7065 to 0.7074). The trace element and isotopic data demonstrate that the Tongshankou adakitic rocks were most probably originated from partial melting of delaminated lower crust with garnet being the main residual mineral whereas little or no plagioclase in the source. On the contrary, the Yinzu adakitic rocks were likely derived from partial melting of thickened lower crust, with residual garnet and a small quantity of plagioclase and hornblende in the source. Interactions between the adakitic magmas and mantle peridotites possibly took place during the ascent of the Tongshankou adakitic magmas through the mantle, considering that MgO, Cr, and Ni contents and eP_Nd(t) values of the adakitic magmas were possibly elevated and initial ⁸⁷Sr/⁸⁶Sr ratios were possibly lowered due to the contamination of mantle peridotites. In addition, the Fe₂O₃ of the adakitic magmas was likely released into the mantle and the oxygen fugacities (?_o2) of the latter were obviously possibly raised, which made metallic sulfide in the mantle oxidized and the chalcophile elements such as Cu were incorporated into the adakitic magmas. The ascent of the adakitic magmas enriched in Cu and Mo will lead to the formation of porphyry Cu‐Mo deposit. Nevertheless, the Yinzu adakitic magmas were possibly lack of metallogenetic materials due to not interacting with mantle peridotite, and thus unfavorable to metal mineralization.     

基于WebGIS的中国湿地信息系统研究

湿地被称为“地球之肾”，具有独特的生态结构与功能。中国湿地面积约占全球湿地面积的10％，但近年来湿地面积逐渐萎缩，已造成了极为严重的生态恶果。因此总结以往湿地研究成果，确立包括遥感在内的各种湿地信息提取方法，形成包含各种湿地信息的湿地数据子库和管理操作这些数据的湿地信息系统，并确立湿地信息的共享与发布机制，从而加快湿地科研步伐，成为湿地与遥感科技工作者共同关注的问题。WebGIS技术是GIS融合Internet技术发展起来的新技术，具有对大批量数据进行有效的分析管理和快速的查询检索功能。基于WebGIS技术的中国沼泽信息系统的建立有效地满足了湿地科研和开发保护的需要。     

Silicon isotope abundance ratios and atomic weights of NBS-28 and other reference materials

The silicon isotope abundance ratios and atomic weights of NBS-28 and several other silicon isotope reference materials were determined in this study. For the calibration of the measurement procedure, two new synthetic isotope mixtures were prepared gravimetrically from highly enriched silicon isotope materials in the form of SiO₂. All materials were converted into SiF₄ gas and subsequently their silicon isotope ratios were measured on the SiF₃⁺ species by using a gas source mass spectrometer MAT-253. The calibrated isotope abundance ratios of NBS-28 are 0.0507446 (26) for ²⁹Si/²⁸Si and 0.0341465 (15) for ³⁰Si/²⁸Si. The corresponding isotopic abundances are 92.17515(28)% for f(²⁸Si), 4.67739(24)% for f(²⁹Si) and 3.14746(14)% for f(³⁰Si). The silicon molar mass of NBS-28 is determined to be 28.08653(11), which is 0.001 larger than previously reported values. In the meanwhile, the ²⁹Si/²⁸Si and ³⁰Si/²⁸Si isotope abundance ratios and atomic weights of SRM-990, IRMM-017, IRMM-018, GBW-04421 and GBW-04422 are also calibrated. These new calibrated data can improve the reliability and comparability of silicon isotope results using above calibrators.     

Long-range Stress Redistribution Resulting from Damage in Heterogeneous Media

— It has been shown in CA simulations and data analysis of earthquakes that declustered or characteristic large earthquakes may occur with long-range stress redistribution. In order to understand long-range stress redistribution, we propose a linear-elastic but heterogeneous-brittle model. The stress redistribution in the heterogeneous-brittle medium implies a longer-range interaction than that in an elastic medium. Therefore, it is surmised that the longer-range stress redistribution resulting from damage in heterogeneous media may be a plausible mechanism governing main shocks.     

Helmert方差分量估计在跨河水准测量中的应用

采用测距三角高程法进行跨河水准测量，可以不量取仪器高，但观测值中有两类不同的观测量。利用Helmert方差分量估计，通过若干次迭代计算，可以更准确地确定两类观测值权的关系，提高了跨河水准测量的平差精度。     

基于椭球面三角格网的数字高程建模

针对传统的DEM在模拟表达大面积地形时具有存在裂缝、地理分析不精确、数据冗余等问题，在椭球面四元三角格网QTM层次剖分的基础上，提出了一种基于椭球面三角格网层次剖分的数字高程建模方法，该方法避免了上述缺陷。应用全球GTOP030数据对该方法进行了验证。     

陀螺经纬仪中零位的稳定性分析

本文分析了陀螺经纬仪的自摆零位对定向精度的影响。悬挂带和导流丝是影响自摆零位稳定性的主要因素，文中提出了几点在工程中稳定自摆零位的技术措施，并在某型号陀螺经纬仪的研制中得到了验证。     

河北省丰宁地区全新世风沙活动及其对古文化的影响

在滦河上游,全新世时期曾有过气候相对湿润阶段,具体表现是:就地起沙的风沙层内,形成了2层特殊的古土壤———黑沙土。黑沙土层分布的厚度不均匀,但具有明显的有机质半固结现象。2层黑沙土之间为黄色风沙层,上层黑沙土又为晚近风沙层覆盖。在下层黑沙土中散布着一些古文化遗存,石片、石核、石斧等石器主要见于下部,陶片数量则以近顶部居多。对黑沙土中的有机质进行14C测年,结果表明,下层黑沙土形成于约7990±150～3200±125aB·P·（cal·）之间,上层黑沙土形成于约3055±170aB·P·（cal·）以后。由这个遗址附近的环境分析证明,古代人类在此活动时期,当地气候处于相对湿润阶段,风沙活动虽依然存在,但可以断定黑沙土的成壤速度大于风沙物质堆积速度,使这里的先民能够依靠农耕、渔猎而生存。大约3200±125aB·P·（cal·）后,风沙堆积速度骤然加快,使黑沙土成土过程一度完全停止,在大约100多年的时间里,风沙活动强烈,形成黑沙土层之间的黄色风沙层堆积。这一时期恶劣的环境使得当时当地的先民无法生存,被迫迁移,从此出现新石器遗址的缺失。该遗址所在的丰宁地区,是影响北京沙尘暴的上源地区之一。因此,该地区环境考古学问题的研究,对了解北京地区沙尘暴变化历史有直接佐证的价值。