基于RegCM4.6的中国地区云对地表太阳辐射的影响研究

使用RegCM4.6区域气候模式,选取Emanuel和Mix（Grell+Emanuel）两种积云对流参数化方案,以2016年为例,分别对中国地区云短波辐射强迫及其涉及的物理量进行数值模拟,揭示其时空分布特征,并探究两种积云对流参数方案模拟效果的差异及其原因。结果表明：从季节平均来看,全国地表云短波辐射强迫均为负值,云对地表为冷却效应,冬季最小,春夏季较大。塔里木盆地四季均为辐射强迫低值区,夏季冷却效应最弱,辐射强迫绝对值低于40 W·m-2;全天空地表净短波辐射分布也呈显著季节差异,除夏季外均呈由南向北逐渐递减的分布趋势;晴空地表净短波辐射在横断山脉处和塔里木盆地处均比较低,其中春季最为明显;两个方案所得的季节空间分布特征大致相同,但在数值上存在差异。春季时全国大部分地区全天空地表净短波辐射通量差异最大,在55 W·m-2左右,晴空地表净短波辐射通量在青藏高原处差异在60W·m-2左右。     

A simple accelerated rock weathering method to predict acid generation kinetics

The development of effective, and economical pre-development waste rock management plans requires an accurate estimate of the quality of drainage generated during mining. This study was conducted to determine if a simple accelerated rock weathering method with lower capital and personnel costs can be used in lieu of the elaborate and costly ASTM method to predict the quality of drainage generated. It involves subjecting rock samples to a constant relative humidity and temperature for 7 days and leach flooding the weathered samples on the 7th day. The acid production rate from the new weathering method correlates quite well with the net neutralization potential generated from the standard acid-base accounting procedure (R²=0.940) which has been demonstrated to be correct 90% of the time in assessing overburden quality, and a mineralogical method (R²=0.924). For investigators interested in generating weathering kinetic parameters, the simple and less costly accelerated weathering method is proposed.     

Contribution of syncollisional felsic magmatism to continental crust growth: A case study of the Paleogene Linzizong volcanic Succession in southern Tibet

The Linzizong volcanic succession (~ 65–45 Ma) and the coeval batholiths (~ 60−40 Ma) of andesitic to rhyolitic composition represent a magmatic response to the India–Asia continental collision that began at ~ 70–65 Ma and ended at ~ 45–40 Ma with convergence continuing to present. These syncollisional felsic magmatic rocks are widely distributed along much of the > 1500 km long Gangdese Belt immediately north of the India–Asia suture (Yarlung–Zangbo) in southern Tibet. Our study of the Linzizong volcanic rocks from the Linzhou Basin (near Lhasa) suggests that syncollisional felsic magmatism may in fact account for much of the net contribution to continental crust growth. These volcanic rocks show a first-order temporal change from the andesitic lower Dianzhong Formation (64.4–60.6 Ma), to the dacitic middle Nianbo Formation (~ 54 Ma), and to the rhyolitic upper Pana Formation (48.7–43.9 Ma). The three formations show no systematic but overlapping Nd–Sr isotope variations. The isotopically depleted samples with ε_Nd(t) > 0 indicate that their primary sources are of mantle origin. The best source candidate in the broad context of Tethyan ocean closing and India–Asia collision is the remaining part of the Tethyan ocean crust. This ocean crust melts when reaching its hydrous solidus during and soon after the collision in the amphibolite facies, producing andesitic melts parental to the Linzizong volcanic succession (and the coeval batholiths) with inherited mantle isotopic signatures. Ilmenite as a residual phase (plus the effect of residual amphibole) of amphibolite melting accounts for the depletion of Nb, Ta and Ti in the melt. The effect of ocean crust alteration plus involvement of mature crustal materials (e.g., recycled terrigeneous sediments) enhances the abundances of Ba, Rb, Th, U, K and Pb in the melt, thus giving the rocks an “arc-like” geochemical signature. Residual amphibole that possesses super-chondritic Nb/Ta ratio explains the sub-chondritic Nb/Ta ratio in the melt; residual plagioclase explains the slightly depleted, not enriched, Sr (and Eu) in the melt, typical of continental crust. These observations and reasoning plus the remarkable compositional similarity between the andesitic lower Dianzhong Formation and the model bulk continental crust corroborates our proposal that continental collision zones may be sites of net crustal growth (juvenile crust) through process of syncollisional felsic magmatism. While these interpretations are reasonable in terms of straightforward petrology, geochemistry and tectonics, they require further testing.     

全球地壳运动的背景场及其研究进展

全球地壳运动是在全球地壳运动背景场中发生的，其背景场的运动参数是表征地壳运动的最基本特征。由于现今板块运动模型ITRF序列均忽略板块边界部分，并且板块以NUVEL1A模型来划分，由此建立的全球板块运动模型不能作为一个严格的全球地壳运动背景场。利用区域速度场和ITRF2000速度场建立一个包括非刚体的板块边界区域和刚体板块的全球地壳运动模型，其板块总角动量ΙLΙ＝0．131°/Ma，即不为零，存在整体旋转，由此建立无整体旋转（NNR）模型，并评述其研究进展。     

天山山区水汽输送气候特征

应用2000～2011年NCEP/NCAR再分析逐日6h 1 1资料,分析了新疆天山山区对流层不同层次空中水汽输送特征,结果表明：(1)天山山区地面～100 hPa每年平均有11504.1×108t水汽输入,11337.0×108t水汽输出,水汽净收支为167.1×108t,其中西、北边界为输入,东、南边界为输出,对流层中层水汽输送量最大,低层次之,高层最小。天山山区水汽总输入量占全新疆水汽输入量的44.1%。(2)各季节中夏季水汽输送量最大,春季、秋季相当,冬季最小,西边界、北边界均为水汽输入边界,东边界、南边界均为水汽输出边界,对流层中层水汽输入量最大。     

1996年5月3日内蒙古包头西M_S6.4级地震的震源机制研究

利用地幔波波形拟合和P波初动符号联合反演的方法,估计了1996年5月3日内蒙古包头西MS6．4级地震的震源机制．得到节面1（40°,70°,－174°）,节面2（308°,84°,－20°）。主压力轴P（-13．95×1017Nm,262°,19°）,主张力轴T（15．66×1017Nm,356°,10°）,中性轴N（B）（1．52×1017Nm,112°,69°）．地震形成左旋走滑兼弱倾滑断裂,断裂面较陡．据ML≥3.0级的余震分布、Ⅷ度区的烈度分布以及宏观震中与微观震中的相对位置推测,节面2可能与实际的地震破裂面相近．据宽频垂直向（BHZ）波形记录中SP与P的到时差估计,震源深度约为21Km．     

平均热点参考基准的建立和岩石圈西向漂移的研究

对于大地测量应用来说,目前IERS机构在定义地球参考系时推荐采用岩石圈无整体旋转(No-Net-Rotation-NNR)约束条件,然而对于地球物理应用来说,相对于NNR参考基准的绝对板块运动数据可能会对地幔对流等研究结果产生误导.考虑到热点的运动,提出建立平均热点(MHS-Medial HotSpot)参考基准的方法,给出建立该基准的约束准则,分别以地学模型NNR-NUVEL1A和实测模型ITRF2005VEL为基础,建立了平均热点参考基准MHS-NUVEL1A和MHS-ITRF2005,并与其它基于热点的绝对板块运动模型进行了比较和分析;讨论了岩石圈的西向漂移,给出了岩石圈相对于下地幔整体旋转的更精确的定量估计,即基于实测的热点参考架MHS-ITRF2005和地学模型NNR-NUVEL1A之间的整体旋转为0.26°/Ma,旋转极在(50°S, 62°E),这与由板块的受力模型给出的岩石圈的整体旋转的旋转极很接近,旋转速率大致快了10%.     

山东刚玉及蓝宝石中天然包裹体的形态与分布特征研究

山东刚玉及蓝宝石中含有大量晶体包裹体和两相、三相包裹体，并沿特定面网和裂理面分布。单个晶体内的显微包裹体数以亿万计，其中两相和三相包裹体的形态十分复杂。     

Web GIS在防震减灾工作中的应用与发展趋势

GIS在大中城市防震减灾系统中得到了广泛的应用,渗透到了地震预报、震害预测、地震区划等各个方面。近年来,随着计算机网络的发展和应用的广泛深入,单机或局域网版GIS软件已不能满足社会发展的要求,利用Internet在Web上发布和出版空间数据,为用户提供空间数据浏览、查询和分析功能已经成为GIS发展的必然趋势。网络地理信息系统WebGIS是Internet技术应用于GIS开发的产物,将WebGIS技术引入防震减灾研究领域,拓宽了地理信息资源的应用领域,提高了空间信息的维护、发布和查询效率,实现了地震信息数据的自动化成图,使全社会范围内的空间数据信息的高度共享成为可能。     

Modelling of evaporation in a sparse millet crop using a two-source model including sensible heat advection within the canopy

During two successive growing seasons meteorological measurements were made in a pearl millet field in the Sahel to investigate the evaporation process in relation to crop growth. The evaporation was measured by eddy correlation and simulated using the Shuttleworth Wallace (SW) model [Q. J. R. Meteorol. Soc. 111 (1985) 839–855]. To take sun height and multi-layer scattering into account a radiation balance model was formulated. The model indicates that partitioning of the net radiation between the vegetation and the soil may be estimated (r²=0.94) from the fraction of diffuse radiation, the leaf area index and an attenuation coefficient, but that the attenuation coefficient may not be similar in different locations. To solve the SW-model with respect to the soil resistance an iterative solution was employed with the total evaporation estimated from the Bowen-ratio calculated from eddy correlation measurements. The procedure made it possible to derive stable estimates of soil resistance at soil evaporation rates down to 25 W m⁻². The soil resistance was found to be in accordance with evaporation through a dry surface layer. The SW-model indicates, that advection of sensible heat from the dry soil to the plants, increases transpiration considerably. This will cause management techniques, such as mulching and dry farming, aimed at reducing soil evaporation to be less effective than might be anticipated. The effects of raising the leaf area index to improve the microclimate is discussed in relation to management of the available water and crop security.