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991.
Lacustrine turbidite of Chang-7 Member in the studied area consists of sihstone and fine sandstone with respect to grain size, which is feldspathic lithie sandstone, syrosem arkose and arkose with respect to mineral constitution affected by provenance. There are such apparent signatures as lithology, sedimentary structure, sedimentary sequence and well logs, to recognize turbidite. During the paleogeographic evolution of Chang-7 Member, lake basin and deep lake are both at their maximum extent during Chang-73 stage, resulting in the deposition of Zhangjiatan shale with widespread extent and of turbidite with fragmental-like. Deep lake line is gradually moving toward lake center and turbidite sand bodies are gradually turning better with better lateral continuity, connectivity and more thickness, from stages of Chang-73, Chang-72 and Chang-7t, which can be favorable reservoir in deep-water.  相似文献   
992.
???????????2002??2003???2004??2005??????????????????????????????????????????????????????????????????Ч??????????????????????????????????????????????????????????????????????????????????????????????????  相似文献   
993.
Two field studies were conducted to measure pigments in the Southern Yellow Sea (SYS) and the northern East China Sea (NECS) in April (spring) and September (autumn) to evaluate the distribution pattern of phytoplankton stock (Chl a concentration) and the impact of hydrological features such as water mass, mixing and tidal front on these patterns. The results indicated that the Chl a concentration was 2.43±2.64 (Mean ± SD) mg m?3 in April (range, 0.35 to 17.02 mg m?3) and 1.75±3.10 mg m?3 in September (from 0.07 to 36.54 mg m?3) in 2003. Additionally, four areas with higher Chl a concentrations were observed in the surface water in April, while two were observed in September, and these areas were located within or near the point at which different water masses converged (temperature front area). The distribution pattern of Chl a was generally consistent between onshore and offshore stations at different depths in April and September. Specifically, higher Chl a concentrations were observed along the coastal line in September, which consisted of a mixing area and a tidal front area, although the distributional pattern of Chl a concentrations varied along transects in April. The maximum Chl a concentration at each station was observed in the surface and subsurface layer (0–10 m) for onshore stations and the thermocline layer (10–30 m) for offshore stations in September, while the greatest concentrations were generally observed in surface and subsurface water (0–10 m) in April. The formation of the Chl a distributional pattern in the SYS and NECS and its relationship with possible influencing factors is also discussed. Although physical forces had a close relationship with Chl a distribution, more data are required to clearly and comprehensively elucidate the spatial pattern dynamics of Chl a in the SYS and NECS.  相似文献   
994.
基于Multipatch模型的冰凌三维可视化分析   总被引:2,自引:0,他引:2  
冰凌作为一种复杂的自然景观与自然灾害,其可视化模拟是冰凌信息管理、监测和预警的重要手段,对防凌减灾工作意义重大。本文深入分析Multipatch数据模型的底层结构,探讨冰凌的三维表达技术途径,提出了复杂冰凌三维可视化的技术实现方法,即模拟冰面的自然形成机理,确定软件系统中冰面在河道中的范围,依据地形DEM数据插值确定冰面边界点高程,模拟冰凌的自然形成过程来切分冰面,采用随机方法生成凌锥和凌柱及其方位角等以体现无序性,以实际照片为纹理贴图以增加真实感,通过虚拟内存、纹理压缩和缓存技术完成三维场景中的冰凌叠加展示。最后,结合系统研究与开发,实现了冰凌三维模型的自动建立和可视化管理。  相似文献   
995.
汶川地震对湖北地震活动趋势的影响   总被引:1,自引:0,他引:1  
探讨汶川地震对湖北地震活动的影响,认为龙门山断裂带与襄樊-广济构造带同属于扬子板块西部和北部边缘,是扬子板块逆冲插入青藏板块和秦岭微板块之下形成的。历史强震统计结果表明,四川中西部及周边强震活动对湖北及周边地区中强地震活动影响明显,且对应率较高。汶川地震后3年内,湖北及周边地区具有发生中等强度地震的可能。同时也指出,近几年湖北及周边的地震活动是汶川地震前期东部地区应力场调整的结果。  相似文献   
996.
EGM96和EGM2008地球重力场模型计算弹道扰动引力的比较   总被引:2,自引:2,他引:0  
给出了利用地球重力场模型计算扰动引力以及重力场模型截断误差的公式,计算了36阶、360阶、2 160阶地球重力场模型在径向和水平方向的截断误差,并对36阶、360阶的EGM96和EGM2008重力场模型计算的弹道扰动引力矢量进行了分析和比较.结果表明,采用重力场模型计算扰动引力时,模型阶数和弹道点的高度越低,模型截断误差越大;EGM96和EGM2008模型的一致性随着模型阶数的升高而逐渐降低.总体来看,EGM2008模型的精度要好于EGM96模型.  相似文献   
997.
结合具体的应用,介绍基于PCI9052接口卡开发过程中一些需要注意的问题。  相似文献   
998.
为了综合确定平北地区的主力烃源岩,深化其油气成藏动力学过程研究,在烃源岩分布特征及有机质丰度、类型和成熟度分析的基础上,应用舍油气盆地数值模拟技术,定量恢复了研究区主要烃源岩层系的生排烃历史。研究表明,平北地区主要发育始新统平湖组、渐新统花港组两套烃源岩系,其中平湖组暗色泥岩为主力烃源岩,具较高的有机质丰度、成熟度、生排烃强度与排烃效率;以平湖组为源岩的油气系统应是本区油气勘探的主要目标。  相似文献   
999.
多效唑对2种海洋微藻生长和抗氧化酶活性的影响   总被引:1,自引:0,他引:1  
运用实验生态学和生物化学的方法,研究了多效唑对青岛大扁藻(Platymonas helgolandica)和绿色巴夫藻(Pavlova viridis)生长和抗氧化酶活性的影响.结果表明:低浓度(≤5 mg/L)多效唑能促进绿色巴夫藻的生长,与对照组相比,多效唑处理组的干重、叶绿素a、可溶性糖和蛋白质含量均有所增加(p<0.05),而低浓度(≤5 mg/L)多效唑对青岛大扁藻的生长无明显影响;高浓度(≥15 mg/L)多效唑可显著抑制青岛大扁藻和绿色巴夫藻的生长,多效唑处理组的干重、叶绿素a、可溶性糖和蛋白质含量均低于对照组(p<0.05).多效唑对青岛大扁藻和绿色巴夫藻的96 h-EC50值分别是28.6 mg/L和24.9 mg/L. 2种微藻经不同浓度多效唑处理后,细胞内抗氧化防御系统的关键性酶超氧化物歧化酶(superoxide dismutase, SOD)和过氧化物酶(peroxidase, POD)均表现为低浓度(≤5 mg/L)的诱导作用和高浓度(≥15 mg/L)时的抑制作用;不同浓度多效唑处理后,2种微藻细胞内过氧化氢酶(catalase, CAT)活性均降低.  相似文献   
1000.
A 21-d laboratory experiment was conducted to study, the phosphorus (P) utilization of two different diets by redlip mullet Liza haematocheila T. & S. Sand-filtered water in salinity 30 and temperatare 25℃ was used. Twenty-nine fish individuals were divided into three groups: 11 to group 1 (G1) fed on diet 1, 11 to group 2 (G2) fed on diet 2, and 7 to contrast group. Diet 1 was a commercial feed, more valuable in nutrition than diet 2 that similar to natural detritus. The results show the intake phosphorus (IP) of G1 was significantly higher than that of G2, and both increased linearly with body size at a certain amount of diet. The retention phosphorus (RP) in fish of G1 was lower than G2. The relationship between retention phosphorus and body size was positive and stronger in G2. Significant difference in faecal phosphorus (FP) was found between G1 and G2. Body size significantly impacted the excretion phosphorus (EP) in G1 but G2. The loss of intake phosphorus in G1 was 10.83-20.27 mg per g fish weight gain, higher than that in G2 for 6.63-9.56. Of the phosphorus, about 10% was allocated into growth, 50% in faeces, and the rest lost in excretion. The main part of phosphorus was lost in faeces but excretion. The phosphorus budget of the fish could be described as 100IP = 7.40RP + 47.39FP + 36.63EP (Diet 1) or 100IP = 11.93RP + 56.64FP + 21.76EP (Diet 2).  相似文献   
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