Magnetic susceptibility variations of the Edicaran cap carbonates in the Yangtze platform and their implications for paleoclimate

1 INTRODUCTION One of the most intriguing phenomena in the late Neoproterozoic (~750 to 543 Ma) is the globa occurrence of thin carbonates that directly overlie glacial deposits in almost every continent (Kennedy 1996; Hoffman et al., 1998; Hoffman and Schrag 2002; Brasier and Shields, 2000; James et al., 2001 Jiang et al., 2003; Nogueira et al., 2003). These “cap carbonates”, commonly several to tens of meters thick, have attracted enormous interests because o their unusually negati…     

CMIP3与CMIP5模式对中国西北干旱区气温和降水的模拟能力比较

通过对15组CMIP3和CMIP5两代模式集合平均对中国西北干旱区气温和降水的模拟能力比较,发现CMIP5模式对气温和降水的模拟更接近观测值。CMIP5模式模拟年、春季、夏季、秋季平均气温的相关系数比CMIP3模式分别提升了0.15、0.13、0.24和0.02,冬季下降了0.07。CMIP5模式对西北干旱区的平均气温变化趋势的模拟效果比CMIP3有所提高,对年、春季、夏季、秋季、冬季趋势的模拟偏差比CMIP3分别减少了0.03℃/10a、0.10℃/10a、0.01℃/10a、0.06℃/10a、0.14℃/10a。对西北干旱区平均气温年、季的模拟偏差分布上,CMIP5模式的偏差均比CMIP3低1~2℃。但是天山区年、季节平均气温的模拟与整体模拟偏低情况相反,CMIP3和CMIP5分别偏高3~6℃和1~4℃,对夏季的模拟偏高最严重,分别达到6℃和4℃。CMIP5模式整体对西北干旱区降水量的模拟结果与观测值的平均相关系数与CMIP3相差不大,均不超过0.1,而且偏差仍然较大。CMIP5模式对西北干旱区的降水量的变化趋势模拟效果比CMIP3有所降低,对年、春季、夏季、秋季、冬季趋势的模拟偏差比CMIP3增加了0.67 mm/10a、0.23 mm/10a、0.51 mm/10a、0.11 mm/10a、0.14 mm/10a。CMIP5模式对年、春季、夏季、秋季和冬季的降水量模拟的均方根误差相比CMIP3分别减少77.6 mm、25.5 mm、25.0 mm、18.8 mm和13.9 mm。在空间上,CMIP5模式对年、季节降水模拟仍然偏高,但是比CMIP3有明显缓解;CMIP3和CMIP5模式对夏季天山区年降水量和夏季降水量的模拟也与大部分区域偏高的趋势明显相反,两代模式对夏季天山区的降水模拟均偏低50 mm左右。     

CBERS-02B星HR与多光谱影像融合及评价

CBERS-02B星搭载了高分辨率全色相机HR和多光谱传感器CCD,HR影像可以与CCD影像融合,优势互补形成新的影像,既保持HR的高空间分辨率又保持CCD的光谱分辨率,HR影像同样可以与其它传感器影像融合形成新的影像。本文使用6种不同的融合方法融合HR与多光谱CCD以及SPOT5多光谱影像,并对融合结果进行了定性和定量评价,得到了HR与SPOT5多光谱影像融合较好的方法,表明了HR与其它传感器影像融合的潜力,同时也对HR和SPOT5多光谱融合影像及与CCD融合影像进行了初步的对比分析。     

TBP－（X－5）反相色谱分离m－NPF分光光度法测定铀

本文研究了以磷酸三丁酯为固定相，大孔聚乙烯苯（Ｘ－５型）为担体的浸渍树脂、垂直型反相色谱柱，对铀分离富集的基本性能，以及铀（Ⅳ）－间硝基苯基萤光酮（ｍ－ＮＰＦ）一氨三乙酸（ＮＴＡ）－吐温－８０显色体系的反应条件，提出了ＴＢＰ（Ｘ－５）分离，ｍ－ＮＰＦ－ＮＴＡ－吐温－８０光度法测定铀，经标准样品验证，结果满意。     

沉积有机质激光热裂解色谱质谱探针分析技术的尝试及其前景探讨

激光热裂解－色谱－质谱分析方法具有从技术层面上融合分子地球化学方法和有机岩石学方法的潜能。通过抚顺煤镜质组分和树脂体的研究实例，介绍了激光热裂解－色谱－质谱探针分析的基本原理及测试方法。抚顺煤显微组分的微区热裂解产物特征中，镜质组和树脂体热解产物的正烷烃、烷基萘和四氢化萘的总体面貌相似，但树脂体中正烷烃含量较低，而烷基四氢化萘明显较高，这可能反映显微组分形成过程中发生过低分子烃类在各显微组分之间的混合作用。除此之外，还把激光热裂解－色谱－质谱探针技术与传统的分子地球化学方法、有机岩石学方法进行比较。探讨了激光热裂解－色谱－质谱探针技术的应用前景以及尚待解决的技术问题。落射到样品表面的激光束能量（温度）和控制和激光辐射时间的，激光束斑大小、热解产物量、色谱－质谱检验灵敏度极限三者关系等，都是限制新技术应用的技术问题。     

采用小径密抗桩一条龙抢治滑坡的方法及效果

以往整治滑坡,较多地使用大口径挖孔桩或钻孔灌注抗滑桩,周期长、成本高。川地208队在治理重庆制药五厂已处于危急态势的滑坡中,采用“天平式”控制、勘治结合、快速抢险,用三排小径密抗桩(300mm口径)整治,取得明显成效。实践表明:浅层滑坡采用较小口径的密抗桩,并辅以排水,能达到事半功倍的效果。     

When are relative variograms useful in geostatistics?

The relative variogram has been employed as a tool for correcting a simple kind of nonstationarity, namely that in which local variance is proportional to local mean squared. In the past, this has been linked in a vague way to the lognormal distribution, although if {Z_t; t D}is strongly stationary and normal over a domain D,then clearly {exp (Z_t); t D}will stillbe stationary, but lognormal. The appropriate link is made in this article through a universal transformation principle. More general situations are considered, leading to the use of a scaled variogram.     

Characteristics of the Variation of Cross Fault Short-Baseline and Short-Range Leveling in Western Yunnan Earthquake Test Site Before Lijiang M_S7.0 Earthquake

Results of analysis of variation of cross fault short-baseline and short-range leveling in Western Yunnan Earthquake Test Site (WYETS), results show that among five observation stations of cross fault short-baseline and short-range leveling in WYETS before the Lijiang MS7.0 Earthquake occurred in February 1996 only Yongsheng observation station (epicentral distance 82 km) located at Chenghai fault shows great variation about one year before the earthquake. And the nearest observation station, Lijiang (epicentral distance 42 km); presents great coseismic variation, but does not show obvious anomalous variation before the earthquake. There are no significant variations related to the earthquake at the other three observation stations. Two methods are used in analysis of the observed data and some valuable results have been obtained.     

Estimation of the 2001 Kunlun earthquake fault slip from GPS coseismic data using Hori’s inverse method

The Hori’s inverse method based on spectral decomposition was applied to estimate coseismic slip distribution on the rupture plane of the 14 November 2001 MS8.1 Kunlun earthquake based on GPS survey results.The inversion result shows that the six sliding models can be constrained by the coseismic GPS data.The established slips mainly concentrated along the eastern segment of the fault rupture,and the maximum magnitude is about 7 m.Slip on the eastern segment of the fault rupture represents as purely left-la...