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161.
为了探明矿物类型对于天然气水合物成藏的影响,笔者等利用南海北部神狐海域W07站位样品及其水合物饱和度数据,进行XRD全岩和黏土矿物测试分析、比表面积分析以及束缚水能力综合分析。结果表明,海床下110~127 m(即110~127 mbsf,meters below sea floor, 海床以下深度)为水合物储层段,海床下127~156 m为非水合物储层段。通过XRD分析可知,高石英及长石含量,低伊蒙混层含量的层段,比表面积与束缚水能力较低,说明其具有相对较好的孔渗条件,为水合物的运移与储集提供了良好的空间条件,因此形成水合物储层段;而在高伊蒙混层的层段中,比表面积较大,束缚水能力较强,其对甲烷气体及流体的吸附和束缚能力较强,对水合物成藏起到潜在的封隔作用,成为非储层段,储层与非储层段纵向叠置序列有利于优质水合物储层的形成。本次研究总结了矿物组分与优质水合物储层之间的关系,并揭示两者存在的潜在成因联系,以期丰富水合物富集成藏的基础理论,对未来南海北部天然气水合物的商业化开发提供支持。 相似文献
162.
文章以非虫黄藻共生型珊瑚Cladopsammia sp.为研究对象,将对照组的海水设置为26℃恒温,试验组从26℃升温至33℃,以此探究海水升温对Cladopsammia sp.代谢和钙化生理的影响。结果显示:在高温胁迫下,虽然Cladopsammia sp.钙化相关酶(Ca2+-ATP酶和Mg2+-ATP酶)的活性出现了负响应,但是珊瑚的呼吸速率、生长速率、组织中总蛋白和粗脂肪都没有显著改变(p>0.05)。比较历史文献结果和本研究结果表明:Cladopsammiasp.可能由于体内没有虫黄藻共生,表现出了比大部分虫黄藻共生珊瑚更高的温度耐受能力。 相似文献
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164.
国家级极端高温短期气候预测系统的研制及应用 总被引:8,自引:0,他引:8
目前,国家级旬、月极端高温预测的业务工作尚未展开,国家级极端高温短期气候预测系统的研制为中国高温预测业务提供了一个有效平台.该系统以百分位相对阈值和35°C、38°C绝对阈值作为高温阈值指标,应用月动力预测模式、动力预测与统计降尺度相结合、物理统计相似三种不同的方法,预测未来1~40天的旬、月极端高温发生概率及高温日数,定期滚动发布预测产品.并以相关系数为衡量指标,应用交叉检验方法对三种方法的预测效果进行分析,结果表明不同方法高相关区的空间分布存在差异,在进行高温预测时,应综合各方法高相关区的预测结果给出综合预测意见.对2007年7月极端高温预测个例分析表明三种方法均有一定的预测技巧. 相似文献
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167.
Xiaolei FU Zhongbo YU Ying TANG Yongjian DING Haishen LYU Baoqing ZHANG Xiaolei JIANG Qin JU 《Journal of Meteorological Research》2019,(2):190-205
Soil moisture is an important variable in the fields of hydrology, meteorology, and agriculture, and has been used for numerous applications and forecasts. Accurate soil moisture predictions on both a large scale and local scale for different soil depths are needed. In this study, a soil moisture assimilation and prediction based on the Ensemble Kalman Filter(EnKF) and Simple Biosphere Model(SiB2) have been performed in Meilin watershed, eastern China, to evaluate the initial state values with different assimilation frequencies and precipitation influences on soil moisture predictions. The assimilated results at the end of the assimilation period with different assimilation frequencies were set to be the initial values for the prediction period. The measured precipitation, randomly generated precipitation,and zero precipitation were used to force the land surface model in the prediction period. Ten cases were considered based on the initial value and precipitation. The results indicate that, for the summer prediction period with the deeper water table depth, the assimilation results with different assimilation frequencies influence soil moisture predictions significantly. The higher assimilation frequency gives better soil moisture predictions for a long lead-time. The soil moisture predictions are affected by precipitation within the prediction period. For a short lead-time, the soil moisture predictions are better for the case with precipitation, but for a long lead-time, they are better without precipitation. For the winter prediction period with a lower water table depth, there are better soil moisture predictions for the whole prediction period. Unlike the summer prediction period, the soil moisture predictions of winter prediction period are not significantly influenced by precipitation. Overall, it is shown that soil moisture assimilations improve its predictions. 相似文献
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169.
太行山迎风坡降水云微物理结构数值模拟分析 总被引:4,自引:2,他引:4
利用MM5模式对太行山迎风坡暴雨过程进行了数值模拟,分析了太行山迎风坡降水的微物理结构特征及山脉对降水的影响。结果表明,降水过程既有太行山地形作用造成的暖云降水又包含汽、水、冰混合的冷云降水,当冰相粒子与液态水的中心上下接近垂直时,1 h降水量最大;地形对于降水增幅作用较大,低层东风遇太行山阻挡辐合抬升形成地形雨;地形造成的弱垂直运动将影响高层上升强度,进而改变水汽分布,并通过微物理过程使得水汽发生相变,该个例中垂直上升运动使得雪和霰相粒子迅速增长,从而导致雨滴增大并克服重力作用下降,在下落过程中捕获低层地形云中水滴变成更大雨滴降落;而在上升过程中水汽凝结释放潜热,对物理量场有一个反馈作用。 相似文献
170.
In this paper, change-points in time series of annual extremes in temperature and precipitation in the Zhujiang River Basin are analyzed with the CUSUM test. The data cover the period 1961–2007 for 192 meteorological stations. Annual indicators are analyzed: mean temperature, maximum temperature, warm days, total precipitation, 5-day maximum precipitation, and dry days. Significant change-points (1986/87, 1997/98, 1968/69, and 2003/04) are detected in the time series of most of the indicators. The change-point in 1986/87 is investigated in more detail. Most stations with this change-point in temperature indicators are located in the eastern and coastal areas of the basin. Stations with this change-point in dry days are located in the western area. The means and trends of the temperature indicators increase in the entire basin after 1986/87. The highest magnitudes can be found at the coast and delta. Decreasing (increasing) tendencies in total and 5-day maximum precipitation (dry days) are mostly observed in the western and central regions. The detected change-points can be explained by changes in the indices of the Western Pacific subtropical high and the East Asian summer monsoon as well as by change-points in wind directions. In years when the indices simultaneously increase and decrease (indices taking reverse directions to negative and positive) higher annual temperatures and lower annual precipitation occur in the Zhujiang River Basin. The high station density and data quality are very useful for spatially assessing change-points of climatic extreme events. The relation of the change points to large-scale oscillation can provide valuable data for planning adaptation measures against climate risks, e.g. for flood control, disaster preparedness, and water resource management. 相似文献