西藏谢通门县北1998年7月20日6.1级地震烈度及灾害损失评估

１９９８年７月２０日西藏谢通门６．１级地震发生在甲岗东麓断层上。宏观震中位于谢通门县青都乡凯仁村附近,震中烈度为Ⅶ度。该地震震害波及１市、１县、１１个乡、７９个行政村,受灾人口２４ ０５８人,受灾面积达６ ７００ｋｍ ２,造成直接经济损失达９ ７６３ ０００元     

地质雷达在公路路面检测中的应用

探讨了地质雷达在公路路面无损检测中的应用,重点介绍了野外资料采集时的参数设置和室内数据处理,以及处理后资料的解释,并给出了应用实例。     

电工专用填料开发研究

主要介绍以粉石英尾矿为原料,开发电工专用填料,提高资源的利用率,充分挖掘其潜在的工业价值和经济价值。     

INDEPTH 与 INDEPTH-MT 项目简介

摘　 要　 介绍了 “国际喜马拉雅和西藏高原深剖面及综合研究” （简称 INDEPTH） 项目概况、 科学目标和已取得的主要科学成果。着重阐述了作为该项目组成部分的由中国地质大学 （北 京）、美国华盛顿大学 （西雅图）、加拿大地质调查局合作进行的 “国际喜马拉雅和西藏高原 深剖面探测的大地电磁研究” （简称 INDEPTH-MT） 的任务、科学目标和主要成果以及采用 的仪器设备、野外数据采集的方法和技术以及数据处理与反演方法所具有的特色和先进性。     

柴达木盆地新构造运动与第四纪气田的形成

柴达木盆地第四纪坳陷形成于上新世晚期到全新世早期的新构造运动期,面积3.7万km²,是欧亚板块与印度板块相碰撞导致祁连山、昆仑山和阿尔金山逐渐上升,柴达木盆地东部相对下降的结果,坳陷内沉积物厚达3200m。 第四纪早期湖深水淡,晚期湖浅水咸。生气层由暗色泥质岩和碳质泥、页岩组成,厚约1500m。生气母质以腐殖型为主。天然气中CH₄/C₂H₆+C₃H₈〉150,δ¹³C〈-60‰。天然气化学成分表明,其为成岩作用早期生物化学作用所形成。储层为细砂岩和粉砂岩,主要为湖滩相、小型河流三角洲相及筛积扇—泉水河—三角洲体系的水下部分。由于尚未充分压实,岩性疏松,孔隙度平均为32％,渗透率60.8～619μm²。盖层为湖相泥岩和含膏泥岩。天然气赋存于自生自储体系之中。主要生气凹陷及生气层殴控制天然气的分布,雁列式背斜带上的局部构造控制天然气的富集。     

关于2次江西早期中强地震的甄别与复核

按照最大化利用有限地震资料的研究思路,充分发掘可利用信息,综合文史记载、人文历史、地震研究成果等资料,对2次江西早期中强地震进行甄别和参数复核,得到结果如下:304年吉水-永丰间地震的震中约为27.3°N、115.2°E,震级5.0级左右; 455年余干地震的震中约为28.7°N、116.7°E,震级5?级左右。该结果可为江西早期地震研究和潜在震源区划分提供新的资料。     

Embodied carbon emissions in China-US trade

China-US trade holds great significance for the world's political and economic landscape. Since 2018, the US government has imposed additional tariffs on Chinese exports on the grounds of the US trade deficit with China. However, the transfer of pollutants embodied in trade and the differences in environmental costs between China and the US have not been widely recognized. In this study, we quantify the embodied carbon emissions(the "virtual" emissions associated with trade and consumption) in China-US trade by constructing a carbon dioxide emissions inventory and a multiregional input-output model.The study shows that the US benefits from a trade surplus of environmental costs by importing energy-intensive and pollutionintensive products from China, which increases China's environmental pollution and abatement costs. In 2017, 288 Mt CO_2 emissions were associated with products produced in China but finally consumed in the US, and only 46 Mt CO_2 were associated with the US products that were consumed in China. From this perspective, China-US trade results in a net transfer of 242 Mt CO_2 per year from the US to China, accounting for approximately 5% of the total CO_2 emissions in the US. More importantly, for Chinese products exported to the US, the carbon emissions embodied in one unit of economic value amount to 0.92 kg/$(RMB:USD=6.8:1), but for US products exported to China, the carbon emissions embodied in one unit of economic value amount to 0.53 kg/$, which means China will incur environmental costs that are 74% higher than those of the US while enjoying the same economic benefits. This environmental trade deficit has burdened China with higher environmental costs than economic benefits.To address this environmental trade deficit, China should actively promote further industrial upgrading and energy structure adjustment and increase investment in innovation and RD, thereby increasing the value added per unit of export products and reducing the environmental cost of producing export products.     

Spatial Variability of Nitrate and Ammonium in Pleistocene Aquifer of Central Yangtze River Basin

It becomes increasingly important and challenging for nitrogen pollution prevention to identify key controls for spatial variability of nitrogen in groundwater that could be affected by multiple factors, including anthropogenic input, groundwater flow, and local geochemistry. This study characterized spatial variability of both nitrate and ammonium in the Pleistocene aquifer of central Yangtze River Basin and assessed the effect of various factors in controlling nitrate and ammonium levels based on multiple statistical approaches (correlation, geostatistics, multiple liner regression). The results indicate that nitrate is mostly influenced by Cl⁻ that represents anthropogenic input, while Eh representing local redox state is a secondary variable influencing nitrate concentrations. The groundwater with elevated nitrate concentrations are estimated to occur mainly in areas with higher-permeability near-surface sediments which can facilitate more anthropogenic nitrate transport and less nitrate removal owing to more oxidized state. Ammonium is mostly correlated to Eh, followed by dissolved organic carbon (DOC), but only DOC improves significantly the accuracy of co-kriging prediction model. The groundwater with elevated ammonium concentrations are estimated to occur mainly in areas with more organic-rich sediments within or around the aquifer which can facilitate more ammonium release owing to natural organic matter consumption accompanying strong reducing conditions. The regional groundwater flow is not a factor significantly controlling nitrate or ammonium levels owing to flat topography and sluggish lateral flow.     

Flood coincidence analysis of Poyang Lake and Yangtze River: risk and influencing factors

We build copula function-based joint distribution models for the annual maximum flood peaks of the Yangtze River and Poyang Lake, to analyze the coincidence probabilities, using scenarios that combine with the impoundment of three Gorges, define influencing indexes and relative contribution rates on flood coincidence at varying frequencies. The study shows the probabilities for coincidence of floods with 1000, 100, and 10-year return periods in both Yangtze main stem and Poyang Lake are respectively 0.02, 0.19 and 2.87%, with higher coincidence probabilities for shorter return periods; when 1000-year flood occurs in the Yangtze, the probabilities for Poyang Lake to encounter flood of the 1000, 100, or 10-year magnitude are higher than 16.08, 42.48 or 74.77% respectively; Poyang–Yangtze flood coincidence is affected by operation of the hydraulic engineering. The lowering of flood peaks caused by the Three Gorges impoundment and regulation of the lake have respectively reduced the probabilities of Poyang–Yangtze flood coincidence by about 7.0 and 1.97%, with average relative contribution rates ? 33.82 and ? 17.1%; influenced by hydrological projects in Poyang basin, variations in Poyang’s inflow flood have displayed an average contribution rate of 20.4% for the negative effect on extreme (P < 5% or P > 90%) flood coincidence, while having a positive contribution rate of 38.2% on floods of other return periods. The results can help increase our understanding of flood coincidence, and support flood control efforts in Poyang Lake; its analytical approach may also be useful to other applications of copula functions.     

Topographic effects up to gravitational curvatures of tesseroids: A case study in China

Studia Geophysica et Geodaetica - Topographic effects on gravity field modeling are important for geodesy, geophysics and related geosciences. In this study we evaluate the gravitational effects of...